Knee flexion contracture impacts functional mobility in children with cerebral palsy with various degree of involvement: a cross-sectional register study of 2,838 individuals

Background and purpose — The impact of knee flexion contracture (KFC) on function in cerebral palsy (CP) is not clear. We studied KFC, functional mobility, and their association in children with CP.Subjects and methods — From the Swedish national CP register, 2,838 children were defined into 3 groups: no (≤ 4°), mild (5–14°), and severe (≥ 15°) KFC on physical examination. The Functional Mobility Scale (FMS) levels were categorized: using wheelchair (level 1), using assistive devices (level 2–4), walking independently (level 5–6). Standing and transfer ability and Gross Motor Function Classification (GMFCS) were assessed.Results — Of the 2,838 children, 73% had no, 14% mild, and 13% severe KFC. KFC increased from 7% at GMFCS level I to 71% at level V. FMS assessment (n = 2,838) revealed around 2/3 were walking independently and 1/3 used a wheelchair. With mild KFC (no KFC as reference), the odds ratio for FMS level 1 versus FMS level 5–6 at distances of 5, 50, and 500 meters, was 9, 9, and 8 respectively. Correspondingly, with severe KFC, the odds ratio was 170, 260, and 217. In no, mild, and severe KFC 14%, 47%, and 77% could stand with support and 11%, 25%, and 33% could transfer with support.Interpretation — Knee flexion contracture is common in children with CP and the severity of KFC impacts function. The proportion of children with KFC rose with increased GMFCS level, reduced functional mobility, and decreased standing and transfer ability. Therefore, early identification and adequate treatment of progressive KFC is important.

Knee flexion contracture is a common problem in children with cerebral palsy (CP) (Miller 2005, Cloodt et al. 2018). Due to muscle imbalance, short and spastic hamstring muscles, and prolonged sitting posture, knee flexion contracture may develop and often progresses in adolescence (Miller 2005, Rodda et al. 2006). Although the exact impact of knee flexion contracture and its contribution to the development of flexed knee gait is still not fully understood, it is associated with progressive deterioration of gait in the ambulating child (Bell et al. 2002, Rodda et al. 2006) and it results in difficulties maintaining functional standing, sitting, and transfer in non-ambulatory children (Miller 2005, Cloodt et al. 2018). In addition, knee flexion contracture generates increased forces on the knee joint, which may cause pain (Rodda et al. 2006, Steele et al. 2012, Schmidt et al. 2020).Prevention of knee flexion contracture has not been thoroughly studied, and physiotherapy treatment and focal spasticity reduction have been attempted without convincing effect (Hägglund et al. 2005, Galey et al. 2017). In ambulatory children, there are several reports of improvement of gait pattern and knee flexion contracture after orthopedic surgery (Ma et al. 2006, Rodda et al. 2006, Stout et al. 2008, Taylor et al. 2016). These studies are limited mainly to children in Gross Motor Function Classification System (GMFCS) level I–III, and occasionally level IV, and varies across age groups as well as according to the surgery performed (Ma et al. 2006, Rodda et al. 2006, Stout et al. 2008, Taylor et al. 2016).The Functional Mobility Scale (FMS), the Pediatric Outcomes Data Collection Instrument (PODCI), and the Gross Motor Function Measure dimension D (GMFM D) are often used to assess function after orthopedic surgery; all three instruments describe how the child actually moves in daily life, and not necessarily what his or her capacity is (Russell 1993, Daltroy et al. 1998, Graham et al. 2004).Knee flexion contracture is easy to assess by physical examination; however, there are limited reports on the prevalence of knee flexion contracture and distribution of functional mobility in larger cohorts of children with CP at all GMFCS levels (Rodby-Bousquet and Hägglund 2010, Cloodt et al. 2018). We studied knee flexion contracture, functional mobility, and their association in children with CP. We assumed that the presence and severity of knee flexion contracture contributes to decreased physical function in children with CP.     

Availability and reporting quality of external validations of machine-learning prediction models with orthopedic surgical outcomes: a systematic review

Background and purpose — External validation of machine learning (ML) prediction models is an essential step before clinical application. We assessed the proportion, performance, and transparent reporting of externally validated ML prediction models in orthopedic surgery, using the Transparent Reporting for Individual Prognosis or Diagnosis (TRIPOD) guidelines.Material and methods — We performed a systematic search using synonyms for every orthopedic specialty, ML, and external validation. The proportion was determined by using 59 ML prediction models with only internal validation in orthopedic surgical outcome published up until June 18, 2020, previously identified by our group. Model performance was evaluated using discrimination, calibration, and decision-curve analysis. The TRIPOD guidelines assessed transparent reporting.Results — We included 18 studies externally validating 10 different ML prediction models of the 59 available ML models after screening 4,682 studies. All external validations identified in this review retained good discrimination. Other key performance measures were provided in only 3 studies, rendering overall performance evaluation difficult. The overall median TRIPOD completeness was 61% (IQR 43–89), with 6 items being reported in less than 4/18 of the studies.Interpretation — Most current predictive ML models are not externally validated. The 18 available external validation studies were characterized by incomplete reporting of performance measures, limiting a transparent examination of model performance. Further prospective studies are needed to validate or refute the myriad of predictive ML models in orthopedics while adhering to existing guidelines. This ensures clinicians can take full advantage of validated and clinically implementable ML decision tools.

Multiple machine learning (ML) algorithms have recently been developed for prediction of outcomes in orthopedic surgery. A recent systematic review demonstrated that 59 models are currently available covering a wide variety of surgical outcomes, such as survival, postoperative complications, hospitalization, or discharge disposition to aid clinical decision-making (Ogink et al. 2021). However, it is imperative that these models are accurate, reliable, and applicable to patients outside the developmental dataset. Even though internal validation studies regularly report good performance, these results are often too optimistic as performance on external validation worsens due to initial overfitting (Collins et al. 2014, Siontis et al. 2015).External validation refers to assessing the model’s performance on a dataset that was not used during development. Testing the developed model on independent datasets addresses the aforementioned concerns of internal validation, including: the generalizability of the model in different patient populations, shortcomings in statistical modelling (e.g., incorrect handling of missing data), and model overfitting (Collins et al. 2014, 2015). Therefore, external validation is essential before a model can be used in routine clinical practice.Although a growing number of ML prediction models are being developed in orthopedics, no overview exists of the number of available ML prediction models that are externally validated, how they perform in an independent dataset, and what the transparency of reporting is of these external validation studies. Therefore, we assessed the proportion, performance, and transparent reporting of externally validated ML prediction models in orthopedic surgery, using the Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis (TRIPOD) guidelines.     

Reasons for revision are associated with rerevised total knee arthroplasties: an analysis of 8,978 index revisions in the Dutch Arthroplasty Register

Background and purpose — From previous studies, we know that clinical outcomes of revision total knee arthroplasty (rTKA) differ among reasons for revision. Whether the prevalence of repeat rTKAs is different depending on the reason for index rTKA is unclear. Therefore, we (1) compared the repeat revision rates between the different reasons for index rTKA, and (2) evaluated whether the reason for repeat rTKA was the same as the reason for the index revision.Patients and methods — Patients (n = 8,978) who underwent an index rTKA between 2010 and 2018 as registered in the Dutch Arthroplasty Register were included. Reasons for revision, as reported by the surgeon, were categorized as: infection, loosening, malposition, instability, stiffness, patellar problems, and other. Competing risk analyses were performed to determine the cumulative repeat revision rates after an index rTKA for each reason for revision.Results — Overall, the cumulative repeat revision rate was 19% within 8 years after index rTKA. Patients revised for infection had the highest cumulative repeat revision rate (28%, 95% CI 25–32) within 8 years after index rTKA. The recurrence of the reason was more common than other reasons after index rTKA for infection (18%), instability (8%), stiffness (7%), and loosening (5%).Interpretation — Poorest outcomes were found for rTKA for infection: over 1 out of 4 infection rTKAs required another surgical intervention, mostly due to infection. Recurrence of other reasons for revision (instability, stiffness, and loosening) was also considerable. Our findings also emphasize the importance of a clear diagnosis before doing rTKA to avert second revision surgeries.

The number of revision total knee arthroplasties (rTKA) has increased over the past years, and projections predict further increases in the coming decades (Kurtz et al. 2007, Patel et al. 2015, LROI 2019). The outcome of these rTKAs is in general inferior compared with the outcome of the primary total knee arthroplasty (Greidanus et al. 2011, Baker et al. 2012, Nichols and Vose 2016). Evidence suggests that one of the determinants for outcome of rTKA is the indication for the revision. To illustrate, several studies have shown a poor prognosis when the rTKA is performed for infection or stiffness compared with revisions for aseptic loosening (Sheng et al. 2006, Pun and Ries 2008, Baker et al. 2012, Van Kempen et al. 2013, Leta et al. 2015). Poor results were reported in terms of complication rates, patient satisfaction, and survival of the prosthesis. However, the majority of these studies based their findings on small samples, and single-center cohorts.A repeat revision indicates that either the initial problem was not resolved despite the index revision, or that another problem occurred. Several reasons for a failed index rTKA can be: inaccurate diagnosis, the decision to choose operative versus nonoperative treatment, surgical failure, the occurrence of complications, or insufficient rehabilitation protocols. Insight into whether the reason for index rTKA is related to the same reason for the repeat rTKA might provide a base for improvement of treatment choices in these revision surgeries.Therefore, we (1) compared the repeat revision rates among the different reasons for index rTKA, and (2) evaluated how often the reason for repeat rTKA was the same as the reason for the index revision.     

Prior hip arthroscopy does not affect 1-year patient-reported outcomes following total hip arthroplasty: a register-based matched case-control study of 675 patients

Background and purpose — Femoroacetabular impingement syndrome (FAIS) is a common cause of hip pain and may contribute to the development of osteoarthritis. We investigated whether a prior hip arthroscopy affects the patient-reported outcomes (PROMs) of a later total hip arthroplasty (THA).Patients and methods — Patients undergoing hip arthroscopy between 2011 and 2018 were identified from a hip arthroscopy register and linked to the Swedish Hip Arthroplasty Register (SHAR). A propensity-score matched control group without a prior hip arthroscopy, based on demographic data and preoperative score from the EuroQoL visual analogue scale (EQ VAS) and hip pain score, was identified from SHAR. The group with a hip arthroscopy (treated group) consisted of 135 patients and the matched control group comprised 540 patients. The included PROMs were EQ-5D and EQ VAS of the EuroQoL group, and a questionnaire regarding hip pain and another addressing satisfaction. Rate of reoperation was collected from the SHAR. The follow-up period was 1 year.Results — The mean interval from arthroscopy to THA was 27 months (SD 19). The EQ-5D was 0.81 and 0.82, and EQ VAS was 78 and 79 in the treated group and the matched control group respectively. There were no differences in hip pain, and reported satisfaction was similar with 87% in the treated group and 86% in the matched control group.Interpretation — These results offer reassurance that a prior hip arthroscopy for FAIS does not appear to affect the short-term patient-reported outcomes of a future THA and indicate that patients undergoing an intervention are not at risk of inferior results due to their prior hip arthroscopy.

Femoroacetabular impingement syndrome (FAIS) implies abnormal morphology on the femoral or acetabular side of the hip joint and is a common cause of hip pain and dysfunction in the young population (Matar et al. 2019, Zhou et al. 2020). It reportedly increases the risk of developing osteoarthritis (OA), presumably due to damage to the chondrolabral structures (Ganz et al. 2003, Beck et al. 2005).Arthroscopic treatment of FAIS has been proven successful with 1- and 5-years’ follow-up (Griffin et al. 2018, Ohlin et al. 2020). However, one of the most common reoperations is conversion to a total hip arthroplasty (THA) (Harris et al. 2013). Depending on the follow-up period and severity of chondrolabral damages, 3–50% of patients with a previous hip arthroscopy for FAIS are reported to undergo THA later in life (Harris et al. 2013).Whether a prior hip arthroscopy affects the result of a subsequent THA (Haughom et al. 2016, Charles et al. 2017, Perets et al. 2017, Hoeltzermann et al. 2019, Vovos et al. 2019) has previously been discussed. However, many of these studies have been underpowered and the results have been incongruent. Most studies suggested no differences in outcomes in THA for patients with a prior hip arthroscopy (Haughom et al. 2016, Charles et al. 2017, Hoeltzermann et al. 2019). Yet inferior patient satisfaction and higher complication rates were reported in some studies (Perets et al. 2017, Vovos et al. 2019).To optimize the results for patients undergoing THA surgery, it is important to understand factors that could affect the outcomes. The possible effect of hip arthroscopy on future THA should also be considered during patient selection.We investigated the influence of a prior hip arthroscopy on a subsequent THA with patient-reported outcome measures (PROMs) 1 year after THA.Open in a separate windowFlow chart of included patients. Excluded diagnoses: tumors, fractures, or trauma. Excluded missing data due to missing preoperatively patient-reported outcomes or demographic data. Abbreviations: SHAR: Swedish Hip Arthroplasty Register, THA: total hip arthroplasty.     

No increased mortality after total hip arthroplasty in patients with a history of pediatric hip disease: a matched,population-based cohort study on 4,043 patients

Background and purpose — Patients with pediatric hip diseases are more comorbid than the general population and at risk of premature, secondary osteoarthritis, often leading to total hip arthroplasty (THA). We investigated whether THA confers an increased mortality in this cohort.Patients and methods — We identified 4,043 patients with a history of Legg–Calvé–Perthes disease (LCPD), slipped capital femoral epiphysis (SCFE), or developmental dysplasia of the hip (DDH) in the Swedish Hip Arthroplasty Register (SHAR) between 1992 and 2012. For each patient, we matched 5 controls from the general population for age, sex, and place of residence, and acquired information on all participants’ socioeconomic background and comorbidities. Mortality after THA was estimated according to Kaplan–Meier, and Cox proportional hazard models were fitted to estimate adjusted hazard ratios (HRs) for the risk of death.Results — Compared with unexposed individuals, patients exposed to a THA due to pediatric hip disease had lower incomes, lower educational levels, and a higher degree of comorbidity but a statistically non-significant attenuation of 90-day mortality (HR 0.9; 95% CI 0.4–2.0) and a lower risk of overall mortality (HR 0.8; CI 0.7–0.9).Interpretation — Patients exposed to THA due to a history of pediatric hip disease have a slightly lower mortality than unexposed individuals. THA seems not to confer increased mortality risks, even in these specific patients with numerous risk factors.

Altered morphology of the hip joint due to pediatric hip diseases, e.g., Legg–Calvé–Perthes disease (LCPD), slipped capital femoral epiphysis (SCFE), or developmental dysplasia of the hip (DDH) is closely linked to early-onset, secondary osteoarthritis (OA) (Jacobsen and Sonne-Holm 2005, Pun 2016) which may lead to total hip arthroplasty (THA) at a young age (Froberg et al. 2011). Thus, the mean age at THA surgery in patients with a history of pediatric hip disease ranges from 38 to 55 years (Traina et al. 2011, Engesaeter et al. 2012), whereas it ranges from 65 to 70 years in patients with primary OA (Engesaeter et al. 2012, Fang et al. 2015, Cnudde et al. 2018). Studies from Nordic countries report that between 4% and 9% of all primary THAs are due to pediatric hip disease (Engesaeter et al. 2012).The long-term outcome and revision rates after THA in patients with previous pediatric hip disease have been studied (Thillemann et al. 2008, Traina et al. 2011), but 90-day mortality and overall mortality after THA in these patients have not yet been investigated. Comorbidities, such as attention deficit hyperactivity disorder (ADHD), depression, cardiovascular disease, hypothyroidism, obesity, and coagulation abnormalities are more common in patients with LCPD and SCFE (Hailer and Nilsson 2014, Perry et al. 2017, Hailer and Hailer 2018, Hailer 2020). In addition, patients with LCPD and SCFE have a higher overall mortality than the general population (Hailer and Nilsson 2014, Hailer 2020). Due to an increased comorbidity burden and possibly increased overall mortality one could therefore fear an increased mortality after THA surgery in these patients.We therefore investigated whether THA surgery in patients with a pediatric hip disease confers an increased 90-day and overall mortality when compared with the general population.     

Rapid decline of yearly number of hip arthroscopies in Sweden: a retrospective time series of 6,105 hip arthroscopies based on a national patient data register

Background and purpose — Hip arthroscopies (HAs) have increased exponentially worldwide and are expected to continue rising. We describe time trends in HA procedures in Sweden (10 million inhabitants) between 2006 and 2018 with a focus on procedure rates, surgical procedures, and patient demographics such as age and sex distribution.Patients and methods — We retrospectively collected data from the Swedish National Patient Register (NPR) for all surgeries including surgical treatment codes considered relevant for HA from 2006 to 2018. Surgical codes were validated through a multiple-step procedure and classified into femoroacetabular impingement syndrome (FAIS) related or non-FAIS related procedure. Frequencies, sex differences, and time trends of surgical procedures and patient demographics are presented.Results — After validation of HA codes, 6,105 individual procedures, performed in 4,924 patients (mean age 34 years [SD 12]) were confirmed HAs and included in the analysis. Yearly HA procedure rates increased from 15 in 2006 to 884 in 2014, after which a steady decline was observed with 469 procedures in 2018. The majority (65%) of HAs was performed in males. Male patients were younger, and surgeries on males more frequently included an FAIS-related procedure.Interpretation — Similar to previous studies in other parts of the world, we found dramatic increases in HA procedures in Sweden between 2006 and 2014. Contrary to existing predictions, HA rates declined steadily after 2014, which may be explained by more restrictive patient selection based on refined surgical indications, increasing evidence, and clinical experience with the procedure.

Hip arthroscopy was long deemed impossible due to anatomic constraints. Easier arthroscopic access to knee and shoulder joints led to an increasing arthroscopy rate in these joints during the 1990s and 2000s (Kim et al. 2011, Colvin et al. 2012a). During the 1990s, improved surgical equipment and techniques enabled surgeons to gain easier access to the hip joint for diagnosis and treatment of a variety of pathologies (Griffiths and Khanduja 2012), including femoroacetabular impingement syndrome (FAIS), acetabular labrum tears, and chondral lesions (Bedi et al. 2013). Arthroscopic hip surgery has been one of the fastest emerging fields within orthopedics and might be at a tipping point for even wider use (Khan et al. 2016a).An exponential worldwide increase in performed HAs has been documented between 2000 and 2013, based on data from private insurance databases (Sing et al. 2015, Maradit Kremers et al. 2017, Bonazza et al. 2018), performance data from surgical trainees (Colvin et al. 2012b, Bozic et al. 2013) and data from national health services (Palmer et al. 2016). While exponentially more patients received HA, evidence for its effectiveness has been questioned (Reiman and Thorborg 2015). In recent years, RCTs have indicated that hip arthroscopy may be more effective than structured rehabilitation in the treatment of FAIS (Griffin et al. 2018, Palmer et al. 2019). The clinical relevance of the statistical superiority for HA found in these trials is debated (Ferreira et al. 2021); however, a continued rise in HA rates has been predicted worldwide (Khan et al. 2016a, Palmer et al. 2016). The only study assessing HA rates beyond 2013 reports declining rates in Finland after 2014 (Karelson et al. 2020). In Sweden, time trends regarding HA have not been investigated. It is therefore unknown whether the rise in HA has continued, or if surgical practice has changed over the years.Therefore, we describe frequency and time trends in performance of hip arthroscopies, with regards to performance rates, surgical procedures, and patient demographics (age and gender distribution) in Sweden.     

Uncemented femoral revision arthroplasty using a modular tapered,fluted titanium stem: 5- to 16-year results of 163 cases

Background and purpose —

Due to the relative lack of reports on the medium- to long-term clinical and radiographic results of modular femoral cementless revision, we conducted this study to evaluate the medium- to long-term results of uncemented femoral stem revisions using the modular MRP-TITAN stem with distal diaphyseal fixation in a consecutive patient series.

Patients and methods —

We retrospectively analyzed 163 femoral stem revisions performed between 1993 and 2001 with a mean follow-up of 10 (5–16) years. Clinical assessment included the Harris hip score (HHS) with reference to comorbidities and femoral defect sizes classified by Charnley and Paprosky. Intraoperative and postoperative complications were analyzed and the failure rate of the MRP stem for any reason was examined.

Results —

Mean HHS improved up to the last follow-up (37 (SD 24) vs. 79 (SD 19); p < 0.001). 99 cases (61%) had extensive bone defects (Paprosky IIB–III). Radiographic evaluation showed stable stem anchorage in 151 cases (93%) at the last follow-up. 10 implants (6%) failed for various reasons. Neither a breakage of a stem nor loosening of the morse taper junction was recorded. Kaplan-Meier survival analysis revealed a 10-year survival probability of 97% (95% CI: 95–100).

Interpretation —

This is one of the largest medium- to long-term analyses of cementless modular revision stems with distal diaphyseal anchorage. The modular MRP-TITAN was reliable, with a Kaplan-Meier survival probability of 97% at 10 years.Long-term outcome of femoral revision arthroplasty depends on proper restoration of joint mechanics by reconstructing the anatomic center of rotation in combination with fixation that provides long-term stability (Gravius et al. 2011).The published medium- to long-term survival rates of cemented revision THA are between 35% and 91% (Kavanagh and Fitzgerald 1985, Retpen et al. 1989, Stromberg and Herberts 1996, Weber et al. 1996). One stage cemented stem revision leads to increased bone loss (Rader and Eulert 2005) and is associated with a much higher rate of re-revision than cementless femoral stem revision (Dohmae et al. 1988). Cemented revision stems only appear to be advisable for less active patients with an average life expectancy of less than 10 years (Weiss et al. 2011). In comparison, uncemented revision hip arthroplasty gives medium- to long-term survival rates of 60–97% (Head et al. 2001, Engh et al. 2002, Kwong et al. 2003).Over the years, uncemented modular revision stems have become increasingly popular (Fink et al. 2009). In complex revision surgery, modular uncemented femoral implants may overcome the limitations of non-modular and mostly straight stems—for example, the difficulty in establishing femoral leg length, femoral anteversion, and soft tissue tension (Berry 2002, Mumme et al. 2004, Gutierrez et al. 2007). Modular cementless implant systems with a distal diaphyseal press-fit concept provide greater variability in difficult anatomical situations than non-modular revision stems (Berry 2002). The modular-designed components offer the opportunity to customize the prosthesis intraoperatively to the individual anatomical situation, allowing nearly physiological joint reconstruction (Gravius et al. 2011).Based on published studies, the modular cementless MRP-TITAN revision stem with its distal diaphyseal fixation concept has well-proven short-term effectiveness in femoral revision, especially for large femoral defects (types IIC and III, as described by Paprosky et al. (1990)). Previous studies have shown low mechanical failure rates of 2–5% after 4–5 years of follow-up (Wirtz et al. 2000, Mumme et al. 2004, 2007).Due to the relative lack of medium- to long-term results of femoral modular cementless revision surgery in the literature, we investigated the clinical and radiographic medium- to long-term outcome of femoral revision arthroplasty with the MRP-TITAN stem in a consecutive patient series.     

Deep neural networks with promising diagnostic accuracy for the classification of atypical femoral fractures

Background and purpose — A correct diagnosis is essential for the appropriate treatment of patients with atypical femoral fractures (AFFs). The diagnostic accuracy of radiographs with standard radiology reports is very poor. We derived a diagnostic algorithm that uses deep neural networks to enable clinicians to discriminate AFFs from normal femur fractures (NFFs) on conventional radiographs.Patients and methods — We entered 433 radiographs from 149 patients with complete AFF and 549 radiographs from 224 patients with NFF into a convolutional neural network (CNN) that acts as a core classifier in an automated pathway and a manual intervention pathway (manual improvement of image orientation). We tested several deep neural network structures (i.e., VGG19, InceptionV3, and ResNet) to identify the network with the highest diagnostic accuracy for distinguishing AFF from NFF. We applied a transfer learning technique and used 5-fold cross-validation and class activation mapping to evaluate the diagnostic accuracy.Results — In the automated pathway, ResNet50 had the highest diagnostic accuracy, with a mean of 91% (SD 1.3), as compared with 83% (SD 1.6) for VGG19, and 89% (SD 2.5) for InceptionV3. The corresponding accuracy levels for the intervention pathway were 94% (SD 2.0), 92% (2.7), and 93% (3.7), respectively. With regards to sensitivity and specificity, ResNet outperformed the other networks with a mean AUC (area under the curve) value of 0.94 (SD 0.01) and surpassed the accuracy of clinical diagnostics.Interpretation — Artificial intelligence systems show excellent diagnostic accuracies for the rare fracture type of AFF in an experimental setting.

Atypical fractures occur at atypical locations in the femoral bone and show a strong association with bisphosphonate treatment (Odvina et al. 2005, 2010, Shane 2010, Shane et al. 2010, Schilcher et al. 2011, 2015, Starr et al. 2018). In contrast to the metaphyseal area, which is the site for the majority of all fragility fractures, the diaphyseal region is where atypical fractures occur. As is the case for any other insufficiency-type fracture of the diaphysis, atypical fractures show specific radiographic features, such as a transverse or short oblique fracture line in the lateral femoral cortex and focal cortical thickening (Schilcher et al. 2013, Shane et al. 2014). These features differ from those of normal femur fractures (NFFs), which show oblique fracture lines and no signs of focal cortical thickening (Shin et al. 2016b).Early and correct diagnosis of AFF is essential for appropriate management (Bogl et al. 2020a), which minimizes the risk of healing complications (Bogl et al. 2020b). In clinical routine practice, conventional radiographs are used to diagnose complete AFF. However, routine diagnostic accuracy is poor, and < 7% of AFF cases are correctly identified in this way (Harborne et al. 2016).Artificial intelligence (AI), deep learning through convolutional networks, has proven effective in the classification (Russakovsky et al. 2015) and segmentation (Ronneberger et al. 2015) of medical images in general, and for bone fractures in particular (Brett et al. 2009, Olczak et al. 2017, Chung et al. 2018, Kim and MacKinnon 2018, Lindsey et al. 2018, Adams et al. 2019, Urakawa et al. 2019, Kalmet et al. 2020). Given the very specific radiographic pattern of these fractures, AI appears to be a useful tool for finding the needle (AFF) in the haystack (NFF).We evaluated the abilities of different deep neural networks to discriminate complete AFF from NFF on diagnostic plain radiographs in an experimental setting and we assessed the effect of limited user intervention on diagnostic accuracy.     

Similar success rates for single and multiple debridement surgery for acute hip arthroplasty infection

Background

Treatment of an acute total hip arthroplasty (THA) infection aims at control of the infection with retention of the implant by surgical debridement and antibiotic treatment. There is no clear evidence whether a single surgical debridement is sufficient or whether multiple procedures are necessary for optimal treatment.

Methods

From a prospective database of patients with acute THA infection, we retrospectively reviewed 68 patients treated in 2 large teaching hospitals. Hospital S used a protocol in which each patient received a single surgical debridement and only additional surgery if infectious symptoms persisted (group S; n = 33). In hospital M, patients always received multiple surgical debridements (group M; n = 35). Both groups received systemic antibiotic treatment. Removal of the implant or persistent infection at follow-up was considered failure of treatment. Mean follow-up of the patients was 5 (2–11) years.

Results

Mean time between implantation and debridement was 19 days. 4 patients in group S were considered failure, as opposed to 10 patients in group M (p = 0.09). 9 patients in group S had additional surgery, which resulted in 3 of the 4 failures. At final follow-up, 30 patients in group S and 33 patients in group M had a good clinical result (p = 0.6).

Interpretation

In patients with acute THA infection, a single debridement with only additional surgery on indication appears to be at least as successful for retention of the primary implant and control of infection as a strategy with multiple surgical debridements.The strategy for treating prosthetic joint infection depends on the type infection encountered. In early postoperative and acute hematogenic infections, the aim of treatment is control of infection and retention of the implant. In contrast, in delayed or late postoperative infections the matured bacterial biofilm cannot be fully removed from the implant and surgical treatment consists of a 1- or 2-stage revision of the implant. Both surgical strategies should be accompanied by a course of systemic antibiotics (Zimmerli et al. 2004, Bernard et al. 2010). To facilitate treatment decisions, algorithms have been developed. Especially the algorithm proposed by Zimmerli et al. (2004) has gained popularity in recent years. Several reports have shown that these guidelines improve success rates (Giulieri et al. 2004, Betsch et al. 2008, De Man et al. 2011).The surgical strategy for retention of the implant consists of extensive irrigation and debridement of the infected joint, often accompanied by the exchange of modular implant components and application of local antibiotic carriers, such as beads or collagen fleeces. However, there is no scientific evidence or consensus as to whether a single surgical debridement is sufficient or whether multiple repeat procedures are necessary for optimal treatment. Studies involving both strategies have been published, with success rates ranging from poor to excellent (Azzam et al. 2010, Estes et al. 2010, Van Kleunen et al. 2010, Aboltins et al. 2013, Geurts et al. 2013, Kuiper et al. 2013, Romano et al. 2013). As a consequence of this, different surgeons use different treatment regimes.We investigated results of 2 different surgical protocols for control of the infection in combination with retention of the primary implant in patients with early postoperative infection after primary THA. We hypothesized that a single-shot debridement regime would be as effective in controlling the infection and retaining the implant as a regime that routinely used multiple surgical debridements.     

Hip dysplasia is not uncommon but frequently overlooked: a cross-sectional study based on radiographic examination of 1,870 adults

Background and purpose — Hip dysplasia in adults is a deformity in which the acetabulum inadequately covers the femoral head. The prevalence is sparingly described in the literature. We investigated the prevalence in Malmö (Sweden) and assessed whether the condition was recognized in the radiology reports.Subjects and methods — All pelvic radiographs performed in Malmö during 2007–2008 on subjects aged 20–70 years with a Swedish personal identity number were assessed. 1,870 digital radiographs were eligible for analysis. The lateral center-edge angle (LCEA) and acetabular index angle (AIA) were measured. Hip dysplasia was defined as an LCEA ≤ 20°. Intraclass correlation coefficients (ICC) for intra-observer measurements ranged from 0.87 (AIA, 95% CI 0.78–0.93) to 0.98 (LCEA, CI 0.97–0.99).Results — The prevalence of hip dysplasia (LCEA ≤ 20°) was 5.2% (CI 4.3–6.3), (98/1,870). There was no statistically significant difference between the sexes for either prevalence of hip dysplasia or mean LCEA. The mean AIA was 0.9° (CI 0.3–1.3) higher in men (4.1 SD 5.5) compared with women (3.2 SD 5.4). The radiologists had reported hip dysplasia in 7 of the 98 cases.Interpretation — The prevalence of hip dysplasia in Malmö (Sweden) is similar to previously reported data from Copenhagen (Denmark) and Bergen (Norway). Our results indicate that hip dysplasia is often overlooked by radiologists, which may influence patient treatment.

Note: Please check the heading levelsHip dysplasia is an anatomical deformity defined by a reduced lateral center-edge angle (LCEA) expressing insufficient acetabular coverage of the femoral head. An angle ≤ 20° is considered pathologic, whereas an angle between 21° and 25° is said to be “borderline” (Wiberg 1939, Fredensborg 1976, Ogata et al. 1990, Jacobsen and Sonne-Holm 2005). The acetabular index angle (AIA) describes the slope of the acetabular roof (Tönnis 1976) and a normal range has been suggested as 3° to 13° (Tannast et al. 2015a). Adult hip dysplasia ranges from being an asymptomatic anatomic variation to a painful disease. Diagnosis requires referral for an anteroposterior (AP) radiograph of the pelvis. Although the radiographic measurements have been known for decades, a diagnostic delay is common as radiologists and clinicians often overlook the deformity (Nunley et al. 2011).The prevalence of hip dysplasia varies from 2% to 8% in the few previous studies and the definition of the diagnosis based on the LCEA is inconsistent (Croft et al. 1991, Smith et al. 1995, Inoue et al. 2000, Jacobsen and Sonne-Holm 2005, Engesaeter et al. 2013). The prevalence has not been studied in Sweden before. In an international comparison, we perceive adult hip dysplasia to be a seldom discussed diagnosis in Sweden. Therefore, we determined the prevalence of hip dysplasia in Malmö, an urban area in southern Sweden, and investigated whether hip dysplasia was recognized in radiologists’ reports.     

30-day and 1-year mortality after skeletal fractures: a register study of 295,713 fractures at different locations

Background and purpose — Few studies have reported the mortality rate after skeletal fractures involving different locations, within the same population. We analyzed the 30-day and 1-year mortality rates following different fractures.Patients and methods — We included 295,713 fractures encountered in patients 16–108 years of age, registered in the Swedish Fracture Register (SFR) from 2012 to 2018. Mortality rates were obtained by linkage of the SFR to the Swedish Tax Agency population register. The standardized mortality ratios (SMR) at 30 days and 1 year were calculated for fractures in any location and for each of 27 fracture locations, using age- and sex-life tables from Statistics Sweden (www.scb.se).Results — The overall SMR at 30 days was 6.8 (95% CI 6.7–7.0) and at 1 year 2.2 (CI 2.2–2.2). The SMR was > 2 for 19/27 and 13/27 of the fracture locations at 30 days and 1 year, respectively. Humerus, femur, and tibial diaphysis fractures were all associated with high SMR, at both 30 days and 1 year.Interpretation — Patients sustaining a fracture had approximately a 7-fold increased mortality at 30 days and over 2-fold increased mortality at 1 year as compared with what would be expected in the general population. High mortality rates were seen for patients with axial skeletal and proximal extremity fractures, indicating frailty in these patient groups.

Compared with other medical conditions, the mortality rate after fractures has been considered to be low, and has not been frequently reported, with the exception of extensive literature on hip femur fractures; for review see Huette et al. (2020). For hip fractures, the importance of organizing care to decrease complications and mortality has been reported (von Friesendorff et al. 2016). Longer waiting time for surgery has reportedly been associated with increased mortality rates in some studies (Schnell et al. 2010, Pincus et al. 2017). A relationship between fractures in different locations and mortality rates can provide information on whether fractures in also other locations should be prioritized for treatment (Vestergaard et al. 2007a, Klop et al. 2017). Fracture types reported to be associated with increased mortality rates are vertebral fractures, distal radius fractures, diaphyseal, and distal femur fractures (Kado et al. 2003, Oyen et al. 2014, Larsen et al. 2020). There are, however, few reports comparing mortality rates for more than a few different fracture locations, within the same population. Hence, comparisons between mortality rates for different fracture locations are difficult.To describe the change in mortality rate associated with a specific condition, the standardized mortality ratio (SMR) is commonly used (Vandenbroucke 1982). We investigated the 30-day and 1-year SMR for patients with fractures in various locations by using data from the Swedish Fracture Register (SFR).     

Determining the development stage of the ossification centers around the elbow may aid in deciding whether to use ESIN or not in adolescents’ forearm shaft fractures

Background and purpose — Elastic stable intramedullary nailing (ESIN) is the preferred method of operative stabilization of unstable pediatric forearm shaft fractures. However, the decision whether to use ESIN or open reduction and internal fixation (ORIF) in older children or teenagers is not always straightforward. We hypothesized that the development stage of the elbow would aid in evaluating the eligibility of the patient for ESIN.Patients and methods — All eligible children, aged <16 years who were treated with ESIN in Oulu University Hospital, during 2010–2019 were included (N = 70). The development stages of 4 ossification centers were assessed according to the Sauvegrain and Diméglio scoring. The proportion of impaired union vs. union was analyzed according to bone maturity, by using the optimal cutoff-points determined with receiver operating characteristics (ROC).Results — Development stage ≥ 6 in the olecranon was associated with impaired union in 20% of patients, compared with none in stages 1–5 (95% CI of difference 8% to 24%). Trochlear ossification center ≥ 4 was associated with impaired union in 17% of patients (CI of difference 7% to 36%) and lateral condyle ≥ 6 in 13% of patients (CI of difference 3.4% to 30%). Proximal radial head ≥ 5.5 was associated with impaired union in 18% of patients (CI of difference 7% to 39%).Interpretation — Recognizing the rectangular or fused olecranon ossification center, referring to stage ≥ 6, was in particular associated with impaired fracture healing. This finding may aid clinicians to consider between ESIN and plating, when treating forearm shaft fracture of an older child or teenager.

Pediatric forearm shaft fractures comprise 6% of all childhood fractures. They occur most frequently in children aged 5–14 years (Wall 2016, Joeris et al. 2017, Alrashedan et al. 2018). Most can be treated nonoperatively, and this is particularly recommended in children < 9 years (Zionts et al. 2005, Franklin et al. 2012). Older children are more prone to complications such as nonunion and redisplacement (Asadollahi et al. 2017). Their longer fracture healing time and less pronounced remodeling capacity have resulted in a trend toward operative management recently (Sinikumpu et al. 2012).Elastic stable intramedullary nailing (ESIN) is the preferred method to fix forearm shaft fractures in children. The method spares periosteal blood supply and surgical wounds are usually far from the fracture. ESIN produces good angular and longitudinal stability (Wall 2016). In older children and teenagers open reduction and internal fixation (ORIF) is optional (Herman and Marshall 2006). Their fractures are more prone to complications and even minor displacement may result in shortening and angulation, thus decreasing pro- and supination, similarly to adult patients (Rehman and Sokunbi 2010). However, the calendar age of a patient does not always match the maturation of the skeleton, making it challenging to select between pediatric-like or adult-like treatment.Bone age of the patient would help the clinician when choosing between ESIN and plating in older children. Bone age could be assessed by additional radiographs of the hand or iliac spine. However, keeping in mind that there are several ossification centers in the elbow, which develop in a particular order in a growing child, we hypothesized that higher development stage of elbow ossification centers would be associated with impaired healing of forearm shaft fractures stabilized by ESIN. We aimed to find a method to predict impaired union of forearm shaft fractures treated by ESIN, by using the Sauvegrain classification system for bone age (Sauvegrain et al. 1962).     

Outcome in adolescence of brachial plexus birth palsy: 69 individuals re-examined after 10–20 years

Background and purpose —

The frequency and severity of a permanent lesion after brachial plexus birth palsy (BPBP) and its impact on activities of daily living are not well documented. We therefore investigated the outcome of BPBP in adolescents, regarding arm function and consequences for activity and participation.

Participants and methods —

Of 30,574 babies born at St. Olavs University Hospital in 1991–2000, 91 had BPBP (prevalence 3 per 1,000), and 69 of these individuals were examined at a median age of 14 (10–20) years. The examination included the modified Mallet classification, range of motion, shoulder rotation and grip strength, Assisting Hand Assessment, and Canadian Occupational Performance Measure. Of the 22 subjects who were not examined, 3 could not be traced and 19 reported having no problems in the affected arm.

Results —

At follow-up, 17 adolescents had a permanent lesion (i.e. individual Mallet subscore below 4) with a median Mallet total score of 15 (9–19), while 52 had good or normal shoulder function (median Mallet total score 25 (23–25)). All participants with a permanent lesion had reduced active shoulder rotation (≤ 15°), 16 had elbow extension deficit, and 10 had subnormal grip strength. External rotation was considerably weaker in the affected shoulder. In addition, they had ineffective use of the affected arm in bimanual activities. Even so, all except 1 were independent in activities of daily living, although 15 experienced minor difficulties.

Interpretation —

Every fourth to fifth child with BPBP had a permanent lesion as an adolescent. External rotation was the most impaired movement. Despite ineffective use of the affected arm in bimanual activities, all of the participants except one were independent in activities of daily living.Brachial plexus birth palsy (BPBP) is caused by a traction injury on the brachial plexus during labor (Metaizeau et al. 1979). The prevalence of BPBP reported varies by a factor of more than 10, from 0.4 to 5.1 per 1,000 live-born (Evans-Jones et al. 2003, Hoeksma et al. 2004, Foad et al. 2008). In Scandinavian populations, a prevalence of 3 per 1,000 live-born has been reported (Lagerkvist et al. 2010, Poyhia et al. 2010).Most children with BPBP have a transient nerve injury, but between 8% and 36% of them will have permanent functional impairments (Michelow et al. 1994, Noetzel et al. 2001, Hoeksma et al. 2004, Poyhia et al. 2010). The extent and severity of the nerve injury, varying from transient neurapraxia to avulsion-type root injuries, are the main predictors of recovery. At the time of diagnosis it is not possible to assess the severity of the injury or to predict the long-term outcome (Sunderland 1991, Hoeksma et al. 2004, Malessy and Pondaag 2011). Some babies may spontaneously recover completely, some may recover partially, and some may need reconstructive nerve surgery. The absence of biceps muscle function at 3 months of age indicates a more severe injury and is also a commonly used indicator for surgical plexus exploration (Gilbert and Tassin 1984, Waters 1999). However, a permanent nerve injury and reduced arm function may also be observed following apparently moderate or less severe injuries.Individuals with a permanent nerve injury after BPBP have various degrees of functional impairment in their affected extremity. These impairments may be due to reduction in muscle strength as well as limited range of motion caused by soft tissue contractures, muscle co-contractions, and secondary osseous deformities (Hardy 1981, Pearl and Edgerton 1998, Hoeksma et al. 2003, Anguelova et al. 2014). Toddlers with incomplete recovery use their affected arm in an asymmetrical way (Lagerkvist et al. 2010). Adults with BPBP have reported problems in activities of daily living (Partridge and Edwards 2004), but there is limited information regarding when these symptoms occur. Moreover, the frequency and the severity of permanent functional impairment in BPBP are not well documented (Pondaag et al. 2004).We studied the long-term outcome of BPBP in adolescents, regarding arm function and consequences for activity and participation.     

Stable glenoid component of reverse total shoulder arthroplasty at 2 years as measured with model-based radiostereometric analysis (RSA)

Background and purpose — Reverse total shoulder arthroplasty (TSA) is used for treating cuff arthropathy, displaced proximal humeral fractures (PHF), and in revision shoulder surgery, despite sparse evidence on long-term results. We assessed stability of the glenoid component in reverse TSA, using model-based RSA.Patients and methods — 20 patients (mean age 76 years, 17 female), operated on with reverse TSA at Oslo University Hospital, in 2015–2017 were included. Indications for surgeries were PHFs, malunion, cuff arthropathy, and chronic shoulder dislocation. RSA markers were placed in the scapular neck, the coracoid, and the acromion. RSA radiographs were conducted postoperatively, at 3 months, 1 year, and 2 years. RSA analysis was performed using RSAcore with Reversed Engineering (RE) modality, with clinical precision < 0.25 mm for all translations (x, y, z) and < 0.7° for rotations (x, z). Scapular “notching” was assessed in conventional radiographs.Results — 1 patient was excluded due to revision surgery. More than half of the patients displayed measurable migration at 2 years: 6 patients with linear translations below 1 mm and 8 patients who showed rotational migration. Except for one outlier, the measured rotations were below 2°. The migration pattern suggested implant stability at 2 years. 10 patients showed radiolographic signs of “notching”, and the mean Oxford Shoulder Score (OSS) at 2 years was 29 points (15–36 points).Interpretation — Stability analysis of the glenoid component of reversed total shoulder arthroplasty using reversed engineering (RE) model-based RSA indicated component stability at 2 years.

Reverse total shoulder arthroplasty (TSA) is a widely used procedure. It was originally intended for cuff arthropathy in elderly patients (Grammont and Baulot 1993), but is presently used for several indications, including acute proximal humeral fractures (PHFs) in the elderly, fracture malunions, chronic dislocations, and revision surgery (Clavert et al. 2019, Rugg et al. 2019, Malahias et al. 2020). For operative treatment of displaced 3- and 4-part PHFs in the elderly, reversed TSA has become the treatment of choice (Critchley et al. 2020), presently down to 60 years of age (Goldenberg et al. 2020).The increased use of reverse TSA has occurred despite sparse evidence concerning long-term clinical outcomes for the implant. However, short-term RSA may predict the longevity of implants (Valstar et al. 2005). For hips and knees, continuous micro-migration over 2 years has shown to be indicative of increased risk of implant loosening (Kärrholm et al. 1994, de Vries et al. 2014). To our knowledge, RSA stability analysis of the glenoid component of reverse TSA in patients has not previously been published.Much concern has been placed on the subject of “notching,” where the polyethylene liner of a reverse TSA over time erodes into the inferior scapular neck (Levigne et al. 2011). Several studies have related notching to poorer outcomes (Mollon et al. 2017, Simovitch et al. 2019), while others have voiced concerns about this causing instability and loosening of the glenoid component (Roche et al. 2013c, Huri et al. 2016).Model-based RSA has the advantage over traditional marker-based RSA of not having to alter implants by attaching markers, and the clinical precision of model-based RSA on the glenoid component is known (Fraser et al. 2018). With increased use, sparse long-term evidence, and with “notching” as the backdrop, we performed a stability analysis of the glenoid component of reversed TSA, using model-based RSA.     

Pain,osteolysis, and periosteal reaction are associated with the STRYDE limb lengthening nail: a nationwide cross-sectional study

Background and purpose — Observing serious adverse events during treatment with the Precice Stryde bone lengthening nail (NuVasive, San Diego, CA, USA), we conducted a nationwide cross-sectional study to report the prevalence of adverse events from all 30 bone segments in 27 patients treated in Denmark.Patients and methods — Radiographs of all bone segments were evaluated regarding radiographic changes in February 2021. We determined the number of bone segments with late onset of pain and/or radiographically confirmed osteolysis, periosteal reaction, or cortical hypertrophy in the junctional area of the nail.Results — In 30 bone segments of 27 patients we observed radiographic changes in 21/30 segments of 20/27 patients, i.e., 19/30 osteolysis, 12/30 periosteal reaction (most often multi-layered), and 12/30 cortical hypertrophy in the area of the junction between the telescoping nail parts. Late onset of pain was a prominent feature in 8 patients. This is likely to be a prodrome to the bony changes. Discoloration (potential corrosion) at the nail interface was observed in multiple removed nails. 15/30 nails were still at risk of developing complications, i.e., were not yet removed.Interpretation — All Stryde nails should be monitored at regular intervals until removal. Onset of pain at late stages of limb lengthening, i.e., consolidation of the regenerate, should warrant immediate radiographic examination regarding osteolysis, periosteal reaction, and cortical hypertrophy, which may be associated with discoloration (potential corrosion) of the nail. We recommend removal of Stryde implants as early as possible after consolidation of the regenerate.

Bone reconstruction and lengthening surgery entails many risks and unplanned surgeries are common (Frost et al. 2021, Morrison et al. 2020, Sheridan et al. 2020). However, since many adverse events can be managed with or without surgical intervention without affecting the long-term outcome, Paley (1990) redefined complications by subdividing these adverse events into problems, obstacles, and complications. Similarly, other groups suggest grading the severity of adverse events (class I–II–IIIA–IIIB) and dividing these into device and non-device-related complications (Black et al. 2015, Frost et al. 2021). The introduction of an all internal Stryde bone lengthening nail (NuVasive, Specialized Orthopedics, San Diego, CA) in May 2018 was a game changer for bone-lengthening surgery because it enabled the majority of patient to fully weight-bear. Furthermore, the first publications showed promising clinical results with only few device-related complications and good biocompatibility without signs of corrosion (Robbins and Paley 2020, Iliadis et al. 2021).However, on February 4, 2021 the Danish Medicines Agency released an urgent field safety notice from NuVasive regarding Stryde and all PRECICE system devices. This notice came to prominence based on the British Medicines & Healthcare products Regulatory Agency (MHRA) identifying safety concerns. In the MHRA reference 2020/012/009/226/001 issued January 20, 2021 one concern that was raised was the “unknown long-term biological safety profile. This includes reports of pain and bony abnormalities at the interface between the telescoping nail segments.”We evaluated the prevalence of radiographic changes in terms of osteolysis, periosteal reactions, and cortical hypertrophy at the junction of the telescoping nail segments as well as late onset of pain and/or swelling in the area.     

Why still in hospital after fast-track hip and knee arthroplasty?

Background and purpose

Length of stay (LOS) following total hip and knee arthroplasty (THA and TKA) has been reduced to about 3 days in fast-track setups with functional discharge criteria. Earlier studies have identified patient characteristics predicting LOS, but little is known about specific reasons for being hospitalized following fast-track THA and TKA.

Patients and methods

To determine clinical and logistical factors that keep patients in hospital for the first postoperative 24–72 hours, we performed a cohort study of consecutive, unselected patients undergoing unilateral primary THA (n = 98) or TKA (n = 109). Median length of stay was 2 days. Patients were operated with spinal anesthesia and received multimodal analgesia with paracetamol, a COX-2 inhibitor, and gabapentin—with opioid only on request. Fulfillment of functional discharge criteria was assessed twice daily and specified reasons for not allowing discharge were registered.

Results

Pain, dizziness, and general weakness were the main clinical reasons for being hospitalized at 24 and 48 hours postoperatively while nausea, vomiting, confusion, and sedation delayed discharge to a minimal extent. Waiting for blood transfusion (when needed), for start of physiotherapy, and for postoperative radiographic examination delayed discharge in one fifth of the patients.

Interpretation

Future efforts to enhance recovery and reduce length of stay after THA and TKA should focus on analgesia, prevention of orthostatism, and rapid recovery of muscle function.Total hip and total knee arthroplasty (THA and TKA) are frequent operations with an average length of stay (LOS) of about 6–12 days in the United Kingdom, Germany, and Denmark (Husted et al. 2006, Bundesauswertung 2009, NHS 2010).During the last decade, however, there has been increased interest in optimal multimodal perioperative care to enhance recovery (the fast-track methodology). Improvement of analgesia; reduction of surgical stress responses and organ dysfunctions including nausea, vomiting, and ileus; early mobilization; and oral nutrition have been of particular interest (Kehlet 2008, Kehlet and Wilmore 2008). These principles have also been applied to THA and TKA, resulting in improvements in pain treatment with multimodal opioid-sparing regimens including a local anesthetic infiltration technique (LIA) or peripheral nerve blocks to facilitate early mobilization (Ilfeld et al. 2006a, b, 2010a, Andersen et al. 2008, Kerr and Kohan 2008), and allowing functional rehabilitation to be initiated a few hours postoperatively (Holm et al. 2010)—ultimately leading to a reduction in LOS (Husted et al. 2008, Barbieri et al. 2009, Husted et al. 2010a, b). Using these evidence-based regimens combined with an improved logistical setup, LOS is reduced to about 2–4 days (Kerr and Kohan 2008, Husted et al. 2010 a,b,c, Lunn et al. 2011).Having well-defined functional discharge criteria is imperative in order to ensure a safe discharge—and it is mandatory if meaningful comparison of LOS is done following alterations in the track (Husted et al. 2008). In the same fast-track setting, an earlier study focused on patient characteristics predicting LOS (Husted et al. 2008). However, little is known about the specific reasons for why patients are hospitalized during the first 1–3 days after THA or TKA; i.e. why can patients not be discharged?We therefore analyzed clinical and organizational factors responsible for being hospitalized in a well-defined prospective setup in a fast-track unit. This unit had previously documented LOS of about 2–3 days (Andersen et al. 2008, Holm et al. 2010, Husted et al. 2010b, c, Lunn et al. 2011).     

The influence of age, delay of repair, and tendon involvement in acute rotator cuff tears: structural and clinical outcomes after repair of 42 shoulders

Background and purpose

Few authors have considered the outcome after acute traumatic rotator cuff tears in previously asymptomatic patients. We investigated whether delay of surgery, age at repair, and the number of cuff tendons involved affect the structural and clinical outcome.

Patients and methods

42 patients with pseudoparalysis after trauma and no previous history of shoulder symptoms were included. A full-thickness tear in at least 1 of the rotator cuff tendons was diagnosed in all patients. Mean time to surgery was 38 (6–91) days. Follow-up at a mean of 39 (12–108) months after surgery included ultrasound, plain radiographs, Constant-Murley score, DASH score, and western Ontario rotator cuff (WORC) score.

Results

At follow-up, 4 patients had a full-thickness tear and 9 had a partial-thickness tear in the repaired shoulder. No correlation between the structural or clinical outcome and the time to repair within 3 months was found. The patients with a tendon defect at follow-up had a statistically significantly lower Constant-Murley score and WORC index in the injured shoulder and were significantly older than those with intact tendons. The outcomes were similar irrespective of the number of tendons repaired.

Interpretation

A delay of 3 months to repair had no effect on outcome. The patients with cuff defects at follow-up were older and they had a worse clinical outcome. Multi-tendon injury did not generate worse outcomes than single-tendon tears at follow-up.“Codman''s trauma theory” postulated that trauma may rupture healthy rotator cuff tendons but that the rupture most often occurs in cases where aged tendons are weakened by overuse or degeneration (Fukuda 2000, Sorensen et al. 2007). Still, cuff ruptures with sudden pseudoparalysis occurring after trauma are usually considered acute, and immediate repair has been recommended (Bassett and Cofield 1983, Lahteenmaki and Lawrence 2007, Petersen and Murphy 2011). Almost all previous studies concerning rotator cuff repair have included patients with both acute and chronic degenerative tears. In the clinical setting, it is difficult to distinguish an acute tear from a degenerative one with acute symptoms after trauma (Bassett and Cofield 1983, Lahteenmaki and Lawrence 2007, Sorensen et al. 2007, Petersen and Murphy 2011). Since there have been few studies, with few participants and including only acute traumatic tears, little is known about the result after repair in this group of patients (Bassett and Cofield 1983, Lahteenmaki and Lawrence 2007, Petersen and Murphy 2011).The Swedish national guidelines state that acute full-thickness tears with pseudoparalysis after trauma in previously asymptomatic patients should be repaired within 3 weeks (Swedish National Musculoskeletal Competence Centre 2006). There is little support for this guideline in the literature. To our knowledge, only a few previous studies have examined the effect of time to surgery after acute traumatic tear. Bassett and Cofield (1983) found that early repair within 3 weeks resulted in better shoulder function but Petersen and Murphy (2011) stated that the clinical outcome is not affected by a surgical delay of 4 months. As stated by Codman and others (Fukuda 2000, Sorensen et al. 2007, Perry et al. 2009, Duquin et al. 2010), most traumatic cuff tears occur in aged tendons. However, the influence of age on the results after acute cuff repair has not been studied in detail.The number of cuff tendons injured has been reported to affect the structural and clinical outcomes in chronic tears, but as far as we know the same correlations have not been reported in patients with acute tears (Jost et al. 2006, Zingg et al. 2007, Nho et al. 2009a, Oh et al. 2009, 2010). Structural defects following repair of chronic tears have been reported to range between 13% and 94% (Fuchs et al. 2006, Jost et al. 2006, Zingg et al. 2007, Oh et al. 2009). To our knowledge, there have been no reports regarding maintenance of tendon integrity following repair of acute tears.We investigated whether the structural and clinical outcomes after surgical repair of an acute rotator cuff tear in a previously asymptomatic patient are influenced by delay in repair, age at repair, and the extent of the initial cuff injury.     

Poor adherence to guidelines in treatment of fragile and cognitively impaired patients with hip fracture: a descriptive study of 2,804 patients

Background and purpose — Following a hip fracture, most patients will encounter poorer functional outcomes and an increased risk of death. Treatment-monitoring of hip fracture patients is in many countries done by national audits. However, they do not allow for a deeper understanding of treatment limitations. We performed a local evaluation study to investigate adherence to 7 best-practice indicators, and to investigate patient groups at risk of suboptimal treatment.Patients and methods — 2,804 patients were surgically treated for a hip fracture from 2011 to 2017 at our institution. Data regarding admission, hospital stay, and discharge was prospectively collected, and adherence to the 7 best practice indicators (nerve block, surgical delay, antibiotics, implant choice, thromboprophylaxis, mobilization, and blood transfusions) was analyzed. Patient groups with lower adherence were identified.Results — 34% of patients received all 7 best practice indicators after considering contraindications; in particular, nerve blocks and thromboprophylaxis displayed low adherence at 61% and 91% respectively. Nursing home residents and patients with cognitive impairment, multiple comorbidities, or low functional levels were at risk of having a lower adherence.Interpretation — The most dependent patients with cognitive impairment, comorbidities, or low functional levels had lower guideline adherence. This large patient subgroup needs a higher treatment focus and more resources. Our findings are likely similar to those in other national and international institutions.

Hip fractures are a leading cause of disability and mortality among seniors worldwide, with 1-year mortality surpassing 20%. Survivors often experience diminished walking ability, reduced activities of daily living, and loss of independence (Bentler et al. 2009, Dyer et al. 2016). Recent years have seen only minimal improvements in outcomes, such as mortality, which suggest that hip fracture treatment needs improvement (Rogmark 2020). However, patients with hip fracture represent a heterogeneous and fragile patient group with multiple comorbidities, which complicates treatment.Evidence-based treatment is fundamental to modern medicine, and previous research has demonstrated improved outcomes for patients receiving best practice indicators (Nielsen et al. 2009, Kristensen et al. 2016, Oakley et al. 2017, Farrow et al. 2018). However, most studies are based on process indicators, which give no information on the actual treatment provided; this includes national audits (Sweden’s National Quality Register 2018, Danish Multidisciplinary Hip Fracture Registry 2019, Royal College of Physicians 2019, Australian & New Zealand Hip Fracture Registry 2019). To our knowledge, only a few studies have evaluated direct local adherence to guidelines for patients with hip fracture (Seys et al. 2018, Mcglynn et al. 2003, Sunol et al. 2015). Continuous monitoring through national audits and local studies might detect gaps in the treatment of patients with hip fracture and hopefully secure improvement.We assessed the degree of adherence to 7 best practice indicators in a local evidence-based guideline for treatment of hip fractures. We expected adherence to increase during the study period as the guideline was incorporated better over time. Furthermore, the study aimed to clarify whether particular patient groups are at risk of significantly lower guideline adherence and hence suboptimal treatment at our institution.     

Surgeons’ behaviors and beliefs regarding placebo effects in surgery

Background and purpose — Emerging evidence from sham-controlled trials suggest that surgical treatment entails substantial non-specific treatment effects in addition to specific surgical effects. Yet, information on surgeons’ actual behaviors and beliefs regarding non-specific treatment and placebo effects is scarce. We determined surgeons’ clinical behaviors and attitudes regarding placebo effects.Methods — A national online survey was developed in collaboration with surgeons and administered via an electronic link.Results — All surgical clinics in Sweden were approached and 22% of surgeons participated (n = 105). Surgeons believed it was important for them to interact and build rapport with patients before surgery rather than perform surgery on colleagues’ patients (90%). They endorsed the importance of non-specific treatment effects in surgery generally (90%) and reported that they actively harness non-specific treatment effects (97%), including conveying confidence and calm (87%), building a positive interaction (75%), and making eye contact (72%). In communication regarding the likely outcomes of surgery, surgeons emphasized accurate scientific information of benefits/risks (90%) and complete honesty (63%). A majority felt that the improvement after some currently performed surgical procedures might be entirely explained by placebo effects (78%). Surgeons saw benefits with sham-controlled surgery trials, nevertheless, they were reluctant to refer patients to sham controlled trials (46%).Interpretation — Surgeons believe that their words and behaviors are important components of their professional competence. Surgeons saw the patient–physician relationship, transparency, and honesty as critical. Understanding the non-specific components of surgery has the potential to improve the way surgical treatment is delivered and lead to better patient outcomes.

Accumulating evidence suggests that the elaborate context surrounding surgical treatment may contribute to considerable placebo effects (Kallmes et al. 2009, Beard et al. 2018). Hence, factors other than the surgical intervention itself could contribute to positive health outcomes, and a recent meta-analysis (including 53 trials and 4,000 patients) reported that in 51% of all placebo-controlled surgical trials there was no statistically better result in the surgical arm compared with the placebo arm (Wartolowska et al. 2014b).Placebo surgery, or sham surgery, is an invasive procedure that has the appearance of a therapeutic intervention, but during which the essential therapeutic maneuver is omitted (Wartolowska et al. 2014). Sham controls can be compared with active treatment in order to elucidate the specific effect of a surgical intervention. Any factors outside the active intervention that affect treatment outcomes can be referred to as non-specific treatment factors. These include, for example, explanations of a treatment (Kam-Hansen et al. 2014), prior experience (Kessner et al. 2013) and the doctor–patient relationship (Kaptchuk et al. 2008).There is significant evidence that non-specific treatment factors impact treatment outcomes, as demonstrated in many different health problems, using a range of different treatment modalities, including placebo pills, creams, and injections (Finniss et al. 2010, Wager and Atlas 2015). As yet, relatively little is known about non-specific treatment effects and placebos in surgery, and in particular about surgeons’ own behaviors and beliefs. Understanding the non-specific components of surgery has the potential to improve the way surgical treatment is delivered, and lead to better outcomes. The aim of the present study was to describe surgeons’ real-world behaviors and attitudes towards placebo effects. There are no previous studies on placebo attitudes among healthcare professionals in Sweden and in contrast to previous studies (Wartolowska et al. 2014a, Baldwin et al. 2016) the present study reports specific behaviors that surgeons engage in when they harness placebo effects.     

Different patient-reported outcomes in immigrants and patients born in Sweden: 18,791 patients with 1 year of follow-up in the Swedish Hip Arthroplasty Register

Background and purpose

Some patients have persistent symptoms after total hip arthroplsty (THA). We investigated whether the proportions of inferior clinical results after total hip arthroplasty—according to the 5 dimensions in the EQ-5D form, and pain and satisfaction according to a visual analog scale (VAS)—are the same in immigrants to Sweden as observed in those born in Sweden.

Methods

Records of total hip arthroplasties performed between 1992 and 2007 were retrieved from the Swedish Hip Arthroplasty Register (SHAR) and cross-matched with data from the National Board of Health and Welfare and also Statistics, Sweden. 18,791 operations (1,451 in immigrants, 7.7%) were eligible for analysis. Logistic and linear regression models including age, sex, diagnosis, type of fixation, comorbidity, surgical approach, marital status, and education level were analyzed. Outcomes were the 5 dimensions in EQ-5D, EQ-VAS, VAS pain, and VAS satisfaction. Preoperative data and data from 1 year postoperatively were studied.

Results

Preoperatively (and after inclusion of covariates in the regression models), all immigrant groups had more negative interference concerning self-care. Immigrants from the Nordic countries outside Sweden and Europe tended to have more problems with their usual activities and patients from Europe and outside Europe more often reported problems with anxiety/depression. Patients born abroad showed an overall tendency to report more pain on the VAS than patients born in Sweden.After the operation, the immigrant groups reported more problems in all the EQ-5D dimensions. After adjustment for covariates including the preoperative baseline value, most of these differences remained except for pain/discomfort and—concerning immigrants from the Nordic countries—also anxiety/depression. After the operation, pain according to VAS had decreased substantially in all groups. The immigrant groups indicated more pain than those born in Sweden, both before and after adjustment for covariates.

Conclusion

The frequency of patients who reported moderate to severe problems, both before and 1 year after the operation, differed for most of the dimensions in EQ-5D between patients born in Sweden and those born outside Sweden.Some patients have persistent symptoms after total hip arthroplasty and are not satisfied with the procedure, with variation from a few up to as much as 30% (Greenwald 1991, Anakwe et al. 2011). In a Swedish nationwide prospective observational study, 5% of patients reported a clinically meaningful reduction in health-related quality of life (HRQoL) and EQ-5D (Rolfson et al. 2011). The outcome of THA surgery may depend on several factors such as the type and severity of the hip disease itself, patient selection, choice of implant, the quality of the surgery, and postoperative rehabilitation. Patient-related factors including ethnicity, cultural and socioeconomic background, educational level, and expectations regarding the procedure are also important (Hawker 2006, Francis et al. 2009, Krupic et al. 2013). Several studies have compared HRQoL between racial/ethnic groups and have documented important disparities, especially related to the experience and management of pain (Tamayo-Sarver et al. 2004, Ezenwa et al. 2006). Chronic pain adversely affects the HRQoL status of black Americans to a greater extent than it affects the HRQoL status of white Americans (Green et al. 2003).Patient-related factors have gained increased acceptance in assessment of the outcome of THA surgery. The Swedish Hip Arthroplasty Register (SHAR) assesses patient satisfaction, pain relief, and HRQoL using the EuroQol System (EQ-5D) (EuroQol 1990, Burstrom et al. 2001, Eisler et al. 2002, Herberts et al. 2004, Garellick et al. 2008, Rolfson et al. 2009). Understanding preoperative information about a THA may be more difficult if the patient is not sufficiently familiar with the language of the country, due to his/her immigrant status. We used the patient-reported outcomes in the SHAR to examine the hypothesis that patients who live in Sweden but have been born outside the country report worse outcome in the EQ-5D score both before and 1 year after hip replacement surgery.