Periprosthetic Femur Fractures After Total Hip Arthroplasty: Does the Mode of Failure Correlate With Classification?

BackgroundPeriprosthetic femur fracture is one of the most common indications for reoperation after total hip arthroplasty. Our objectives were to evaluate the incidence of reoperation after the surgical treatment of periprosthetic femur fractures and to compare the mechanisms of failure between fractures around a stable femoral component and those with an unstable femoral component.MethodsWe identified a consecutive series of 196 surgically treated periprosthetic fractures after total hip arthroplasty between 2008 and 2017. Mean age was 72 years (range, 29-96 years), and 108 (55%) were women. The femoral component was unstable in 127 cases (65%) and stable in the remaining 69 cases (35%). Mean follow-up was 2 years.ResultsThe 2-year cumulative probability of any reoperation was 19%. The most common indication for reoperation among the cases with a stable femoral component was nonunion, and the most common indication for reoperation among the cases with an unstable femoral component was infection. Fractures that originated at the distal aspect of the femoral component were associated with a high risk of nonunion (6 of 28 cases, P < .01) and reoperation (9 of 28 cases, P = .03).ConclusionSurgeons should take measures to mitigate the failure modes that are distinct based on fracture type. The high infection rate after surgical management of B₂ fracture suggests that additional antiseptic precautions may be warranted. For B₁ fractures, particularly those originating near the distal aspect of the femoral component, augmenting fixation with orthogonal plating, spanning the entire femur, or revising the stem in cases of poor proximal bone should be considered.     

Limb Length Discrepancy in Total Hip Arthroplasty: Is the Lesser Trochanter a Reliable Measure of Leg Length?

BackgroundLimb length discrepancy (LLD) after total hip arthroplasty may affect clinical outcomes and patient satisfaction. Preoperative LLD estimates on anteroposterior pelvic radiographs fail to account for anatomical limb variation distal to the femoral reference points. The objective of this study is to determine how variations in lower limb skeletal lengths contribute to true LLD.MethodsFull-length standing anteroposterior radiographs were used to measure bilateral leg length, femoral length, and tibial length. Leg length was evaluated using 2 different proximal reference points: the center of the femoral head (COH) and the lesser trochanter (LT). Mean side-to-side discrepancy (MD) and percentage asymmetry (%AS) for each measurement were evaluated in the overall cohort and when stratified by patient demographic variables.ResultsOne hundred patients were included with an average age of 62.9 ± 11.2 years. Average femoral length was 434.0 ± 39.8 mm (MD 4.3 ± 3.5 mm) and tibial length was 379.9 ± 34.6 mm (MD 5.9 ± 12.7 mm). Average COH-talus was 817.5 ± 73.2 mm (MD 6.4 ± 5.1 mm). Average LT-talus was 760.5 ± 77.6 mm (MD 5.8 ± 5.1 mm). Absolute asymmetry >10 mm was detected in 16% of patients for COH-talus and 15% for LT-talus, while %AS >1.5% was detected in 13% of patients for COH-talus and 18% for LT-talus. Female gender was associated with increased femoral length %AS (P = .037).ConclusionApproximately 1 in 6 patients have an LLD of >10 mm when measured from either the LT or COH. Surgeons using either of these common femoral reference points to estimate LLD on pelvic radiographs should consider these findings when planning for hip reconstruction.Level of EvidenceLevel III.     

Does Tibial Rotation Correlate With Femoral Anteversion? Implications for Hip Arthroplasty

The aim of the study was to assess the magnitude and variability of rotation of ipsilateral femur and tibia and to identify the existence of rotational correlations. Femoral rotation (FR) and tibial rotation (TR) were measured with computed tomography in 151 consecutive patients when total hip arthroplasty was planned. Median FR was 14 degrees (range, -23 degrees to 91 degrees ) and median TR was 38 degrees (range, 15 degrees -76 degrees ). Femoral rotation was significantly higher in females, in left femora, in the presence of secondary osteoarthritis, and in hip dysplasia. Tibial rotation was significantly higher in females. Femoral rotation and TR positively correlated (r = 0.2963, P = .0001). The magnitude of TR and FR was found to be dependent on each other. Disregarding the variability and magnitude of TR may result in asymmetrical foot positioning after correction of FR during total hip arthroplasty.     

Predictors and Functional Implications of Change in Leg Length After Total Knee Arthroplasty

Background

Leg lengthening occurs in 83% of primary total knee arthroplasty (TKA). The effects of leg length discrepancy (LLD) on THA patients are well established. However, patient function and satisfaction associated with LLD after primary TKA has not been analyzed. This study aimed to quantify the magnitude of limb lengthening, identify radiographic and perceived LLD, and correlate these with predictive factors and functional outcomes in a series of TKA patients.

Do Medial Pivot Kinematics Correlate With Patient-Reported Outcomes After Total Knee Arthroplasty?

Background

Many total knee arthroplasty (TKA) implants are designed to facilitate a medial pivot kinematic pattern. The purpose of this study was to determine whether intraoperative medial pivot kinematic patterns are associated with improved patient outcomes.

Does Multiple Sclerosis Affect the Inpatient Perioperative Outcomes After Total Hip Arthroplasty?

Background

There is a paucity of studies evaluating the short-term perioperative outcomes of total hip arthroplasty (THA) in multiple sclerosis (MS) patients. Therefore, this study evaluated (1) patient factors; and (2) patient outcomes in MS THA patients compared to non-MS THA patients.

Revision Surgery for Instability After Total Hip Arthroplasty: Does Timing Matter?

BackgroundInstability is a common reason for revision surgery after total hip arthroplasty (THA). Recent studies suggest that revisions performed in the early postoperative period are associated with higher complication rates. The purpose of this study is to assess the effect of timing of revision for instability on subsequent complication rates.MethodsThe Medicare Part A claims database was queried from 2010 to 2017 to identify revision THAs for instability. Patients were divided based on time between index and revision surgeries: <1, 1-2, 2-3, 3-6, 6-9, 9-12, and >12 months. Complication rates were compared between groups using multivariate analyses to adjust for demographics and comorbidities.ResultsOf 445,499 THAs identified, 9298 (2.1%) underwent revision for instability. Revision THA within 3 months had the highest rate of periprosthetic joint infection (PJI): 14.7% at <1 month, 12.7% at 1-2 months, and 10.6% at 2-3 months vs 6.9% at >12 months (P < .001). Adjusting for confounding factors, PJI risk remained elevated at earlier periods: <1 month (adjusted odds ratio [aOR]: 1.84, 95% confidence interval [CI]: 1.51-2.23, P < .001), 1-2 months (aOR: 1.45, 95% CI: 1.16-1.82, P = .001), 2-3 months (aOR: 1.35, 95% CI: 1.02-1.78, P = .036). However, revisions performed within 9 months of index surgery had lower rates of subsequent instability than revisions performed >12 months (aOR: 0.67-0.85, P < .050), which may be due to lower rates of acetabular revision and higher rates of head-liner exchange in this later group.ConclusionWhen dislocation occurs in the early postoperative period, delaying revision surgery beyond 3 months from the index procedure may be warranted to reduce risk of PJI.     

Do Patients With Psychological Distress Have Poorer Patient-Reported Outcomes After Total Hip Arthroplasty?

BackgroundPatients with psychological distress are likely to have poorer short-term functional outcomes after total knee arthroplasty. However, the influence of psychological distress on the outcomes of total hip arthroplasty (THA) is relatively understudied. Previous studies also had short follow-ups of 1 year or less. We examined the influence of psychological distress on patient-reported outcomes and satisfaction, and analyzed the change in mental health after THA at a minimum of 2 years.MethodsProspectively collected data of 1384 patients undergoing primary THA in 2001-2015 were reviewed. Patients were assessed using the Oxford Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index, and 36-item Short-Form health survey Physical Component Summary and Mental Component Score (MCS). Patients were stratified into those with psychological distress (MCS < 50, n = 720) and those without (MCS ≥ 50, n = 664). Multiple regression analysis was used to control for age, gender, body mass index, and baseline scores. The rate of satisfaction and expectation fulfillment was also analyzed.ResultsDistressed patients had a poorer Physical Component Summary at 6 months. However, there was no difference in patient-reported outcomes at 2 years. A higher proportion of distressed patients attained the minimal clinically important difference for Oxford Hip Score and Western Ontario and McMaster Universities Osteoarthritis Index, while 92.2% of distressed patients and 92.9% of nondistressed patients were satisfied at 2 years (P = .724). There was no difference in MCS after 6 months. The percentage of distressed patients also declined from 41.8% to 27.3%.ConclusionPatients with psychological distress achieved a comparable level of function, quality of life, and satisfaction 2 years after THA. Undergoing THA may also lead to mental health improvement in a subgroup of distressed patients.     

Understanding the Main Predictors of Length of Stay After Total Hip Arthroplasty: Patient-Related or Procedure-Related Risk Factors?

BackgroundRemoving total hip arthroplasty (THA) from the Centers for Medicare & Medicaid Services (CMS) inpatient-only list allows Medicare to cover outpatient THA, driving hospitals to recommend outpatient surgery for appropriate patients and raising safety concerns over which patients’ admissions should remain inpatient. Thus, we aimed to determine the influence of patient-related and procedure-related risk factors as predictors of >1-day Length of Stay (LOS) after THA.MethodsA prospective cohort of 5281 patients underwent primary THA from 2016 to 2019. Risk factors were categorized as patient-related or procedure-related. Multivariable cumulative link models identified significant predictors for 1-day, 2-day, and ≥3-day LOS. Discriminating 1-day LOS from >1-day LOS, we compared performance between two regression models.ResultsA>1-day LOS was significantly associated with age, female gender, higher body mass index, higher Charlson Comorbidity Index, Medicare status, and higher Hip disability and Osteoarthritis Outcome Physical Function Shortform(HOOS-PS) and lower Veterans RAND12 Mental Component (VR-12 MCS) scores via the initial regression model that contained patient factors only. A second regression model included procedure-related risk factors and indicated that procedure-related risk factors explain LOS more effectively than patient-related risk factors alone, as Akaike information criterion (AIC) increased by approximately 1100 units upon removal from the model.ConclusionAlthough patient-related risk factors alone provide predictive value for LOS following THA, procedure-related risk factors remain the main drivers of predicting LOS. These findings encourage examination of which specific procedural risk factors should be targeted to optimize LOS when choosing between inpatient and outpatient THA, especially within a Medicare population.     

Does Trochanteric Osteotomy Length Affect the Amount of Proximal Trochanteric Migration During Revision Total Hip Arthroplasty?

BackgroundNonunion and proximal trochanteric migration is a known complication of trochanteric osteotomy. This study examines the effect of osteotomy length on proximal greater trochanter (GT) migration.MethodsWe analyzed 113 modified trochanteric slide osteotomies and 73 extended trochanteric osteotomies performed between 2008 and 2016. All osteotomies were fixed using cerclage wires and had minimum 6-month radiographic follow-up. Spearman correlations were used to assess association between osteotomy length and GT migration distance. Chi-squared test and logistic regression were used to assess association between patient and surgical factors and GT migration >1 cm. Receiver operating characteristic curves were constructed to determine the optimal cutoff osteotomy length for predicting GT migration >1cm.ResultsMean osteotomy length was 6.1 cm (range 3-12) for modified trochanteric slide osteotomies and 14.8 cm (range 8-23) for extended trochanteric osteotomies. Osteotomy length was negatively correlated (r = ?0.340, P < .001) with GT migration distance. Longer osteotomy length was protective against GT migration >1 cm (odds ratio 0.67, P = .002). Receiver operating characteristic curve analysis demonstrated an optimal cutoff osteotomy length of 9.8 cm for predicting GT migration >1 cm (sensitivity 0.971, specificity 0.461). Among osteotomies <10 cm, those fixed using at least one distal wire below the lesser trochanter and vastus ridge demonstrated less mean GT migration (3.86 vs 7.12 mm, P = .009) and higher mean union rate (68.8% vs 31.2%, P < .001).ConclusionOsteotomies shorter than 10 cm are at higher risk of developing proximal GT migration >1 cm. A distal cerclage wire below the lesser trochanter and vastus ridge may help decrease the amount of GT migration.Level of EvidencePrognostic Level IV.     

Does Vitamin D Status Affect the Attainment of In-Hospital Functional Milestones After Total Hip Arthroplasty?

Our study aims to identify the prevalence of low vitamin D status in patients undergoing total hip arthroplasty (THA) and to evaluate the association between serum vitamin D level and the attainment of in-hospital functional milestones. We collected data from patients who underwent THA and had preoperative serum vitamin D (serum 25-hydroxy vitamin D) levels measured. From 200 patients, 79 (39.5%) had low serum vitamin D (serum 25-hydroxy vitamin D <32 ng/mL). There were no associations between serum vitamin D level and the attainment of in-hospital functional milestones as well as length of hospital stay or perioperative complications after THA. Because low vitamin D status did not compromise the short-term functional outcomes after THA, surgery need not be delayed, but low vitamin D levels should be corrected once identified.     

Does Functional Cup Orientation Change at Minimum of 10 Years After Primary Total Hip Arthroplasty?

BackgroundCup orientation has been shown to influence the postoperative risk of impingement and dislocation following total hip arthroplasty (THA) and may change over time due to changes in pelvic tilt that occur with aging. The purpose of this study is to determine if there is a significant change in acetabular cup inclination and anteversion over a 10-year period following THA.MethodsA retrospective, multisurgeon, single-center cohort study was conducted of 46 patients that underwent THA between 1995 and 2002. A total of 46 patients were included, with a median age at surgery of 56 years, and a median time between initial postoperative radiograph and the most recent one being 13.5 years (minimum 10 years). Cup orientation was measured from postoperative and follow-up supine anterior-posterior pelvic radiographs. Using a validated software, inclination and anteversion were calculated at each interval and the change in cup anteversion and inclination angle was determined. Furthermore, the difference in the sacro-femoral-pubic angle was measured, reflecting the difference in pelvic tilt between intervals.ResultsNo significant difference was detected between measurements taken from initial postoperative radiograph and measurements a minimum of 10 years later (P > .45), with the median (interquartile range) change in anteversion, inclination, and sacro-femoral-pubic being 0° (−1° to 3°), 1° (−3° to 2°), and 0° (−2° to 3°), respectively.ConclusionOur study found no significant change in functional cup orientation a minimum of 10 years after THA. No shifts in functional cup orientation as a result of altering spinopelvic alignment seemed to be present over a 10-year period.     

Does Disability Correlate With Impairment After Hand Injury?

Background

Any loss or deviation in body function and structure is considered impairment, whereas limitations on activities are fundamental to the definition of disability. Although it seems intuitive that the two should be closely related, this might not be the case; there is some evidence that psychosocial factors are more important determinants of disability than are objective impairments. However, the degree to which this is the case has been incompletely explored.

Questions/purposes

The purpose of this study was to determine if disability (as measured by the Disabilities of the Arm, Shoulder and Hand [DASH] and the Michigan Hand Questionnaire [MHQ]) and pain intensity correlate with impairment (as measured by the American Medical Association [AMA] impairment guide). Secondary study questions addressed the effect of pain intensity and symptom of depression on predicting disability.

Methods

Impairment and disability were evaluated in a sample of 107 hand-injured patients a mean of 11 months after injury. Impairment rating was performed prospectively. From the patients who came for therapy, they were invited to fill out the questionnaire and evaluated for impairment rating. Response variables of DASH, MHQ, and visual analog scale pain intensity values were collected at the same setting. Other explanatory variables included demographic, injury-related, and psychological factors (symptoms of depression measured with the Beck Depression Inventory). Initial bivariate and multivariate analyses were performed to determine correlations of disability and pain to impairment rating and other exploratory variables.

Results

Disability as measured by the DASH showed intermediate correlation with AMA impairment (r = 0 .38, beta = 0.36, p = 0.000). Together with gender, it accounted for only 22% of the variability in DASH scores. Similarly, MHQ score correlated with impairment rating (r = −0.24, beta = −0.23, p < 0.05). However, together with age, injured hand accounted for only 19% of the variability in MHQ scores. However, pain intensity did not correlate with impairment (r = −0.46, p > 0.05). Interestingly, pain intensity did correlate with the time passed from surgery but it was correlated with symptom of depression (r² = 0.10, beta = 0.33, p = 0.001).

Conclusions

The limited correlation between impairment and disability emphasizes the importance of factors other than pathophysiology in human illness behavior. These may include physical (pain, dominant injured hand) and conditional factors (time since surgery) or psychological factors such as depression and adapting; all mentioned can be considered as personal factors that may be different in each patient. So considering personal difference and any other condition except the impairment alone can help to better plan interventions and also diminish disability level.

Level of Evidence

Level III, therapeutic study.     

Can Squeaking With Ceramic-On-Ceramic Hip Articulations In Total Hip Arthroplasty Be Avoided?

Squeaking is a recognized complication of total hip arthroplasty with ceramic on ceramic bearings but the etiology has not been well identified. We evaluated 183 hips in 148 patients who had undergone ceramic-on-ceramic noncemented total hip arthroplasties at one center between 1997–2007 by standardized telephone interviews and radiographic review. Audible squeaking was reported from 22 hips (12% of 183) of 19 patients. Prevalence of squeaking was associated with younger age; obesity; lateralized cup position; use of beta titanium alloy femoral components and shortened head length options; and higher reported activity level, greater pain, and decreased satisfaction at the time of the interview. Squeaking was described as having little personal significance by most patients. Squeaking might be preventable in part through medialization of the acetabular cup and avoidance of the use of shortened femoral necks.     

Does Acetabular Retroversion Affect Range of Motion after Total Hip Arthroplasty?

Background  

Increasingly, acetabular retroversion is recognized in patients undergoing hip arthroplasty. Although prosthetic component positioning is not determined solely by native acetabular anatomy, acetabular retroversion presents a dilemma for component positioning if the surgeon implants the device in the anatomic position.