Role of preoperative pain,muscle function,and activity level in discharge readiness after fast-track hip and knee arthroplasty

Methods Before surgery, hip pain (THA) or knee pain (TKA), lower-extremity muscle power, functional performance, and physical activity were assessed in a sample of 150 patients and used as independent variables to predict the outcome (dependent variable)—readiness for hospital discharge —for each type of surgery. Discharge readiness was assessed twice daily by blinded assessors.Results Median discharge readiness and actual length of stay until discharge were both 2 days. Univariate linear regression followed by multiple linear regression revealed that age was the only independent predictor of discharge readiness in THA and TKA, but the standardized coefficients were small (≤ 0.03).Interpretation These results support the idea that fast-track THA and TKA with a length of stay of about 2–4 days can be achieved for most patients independently of preoperative functional characteristics.Over the last decade, length of stay (LOS) with discharge to home after primary THA and TKA has declined from about 5–10 days to about 2–4 days in selected series and larger nationwide series (Malviya et al. 2011, Raphael et al. 2011, Husted et al. 2012, Kehlet 2013, Hartog et al. 2013, Jørgensen and Kehlet 2013). However, there is a continuing debate about whether selected patients only or all patients should be scheduled for “fast-track” THA and TKA in relation to psychosocial factors and preoperative pain and functional status (Schneider et al. 2009, Hollowell et al. 2010, Macdonald et al. 2010, Antrobus and Bryson 2011, Jørgensen and Kehlet 2013), or whether organizational or pathophysiological factors in relation to the surgical trauma may determine the length of stay (Husted et al. 2011, Husted 2012).We studied the role of THA and TKA patients’ preoperative pain and functional characteristics in discharge from 2 orthopedic departments with well-established fast-track recovery regimens (Husted et al. 2010).     

Missed low-grade infection in suspected aseptic loosening has no consequences for the survival of total hip arthroplasty: 173 patients followed for 6 to 9 years

Background and purpose — Aseptic loosening and infection are 2 of the most common causes of revision of hip implants. Antibiotic prophylaxis reduces not only the rate of revision due to infection but also the rate of revision due to aseptic loosening. This suggests under-diagnosis of infections in patients with presumed aseptic loosening and indicates that current diagnostic tools are suboptimal. In a previous multicenter study on 176 patients undergoing revision of a total hip arthroplasty due to presumed aseptic loosening, optimized diagnostics revealed that 4–13% of the patients had a low-grade infection. These infections were not treated as such, and in the current follow-up study the effect on mid- to long-term implant survival was investigated.Patients and methods — Patients were sent a 2-part questionnaire. Part A requested information about possible re-revisions of their total hip arthroplasty. Part B consisted of 3 patient-related outcome measure questionnaires (EQ5D, Oxford hip score, and visual analog scale for pain). Additional information was retrieved from the medical records. The group of patients found to have a low-grade infection was compared to those with aseptic loosening.Results — 173 of 176 patients from the original study were included. In the follow-up time between the revision surgery and the current study (mean 7.5 years), 31 patients had died. No statistically significant difference in the number of re-revisions was found between the infection group (2 out of 21) and the aseptic loosening group (13 out of 152); nor was there any significant difference in the time to re-revision. Quality of life, function, and pain were similar between the groups, but only 99 (57%) of the patients returned part B.Interpretation — Under-diagnosis of low-grade infection in conjunction with presumed aseptic revision of total hip arthroplasty may not affect implant survival.Aseptic loosening and infection are 2 common causes of revision in total hip arthroplasty (THA) (Sadoghi et al. 2013). Data from the Norwegian Arthroplasty Register and the Swedish Hip Arthroplasty Register have shown that antibiotic prophylaxis, administered either systemically, locally, or combined, prevents infection and thus reduces revision rates due to infection. Interestingly, it has also been shown that the rates of revision due to aseptic loosening decrease with the use of antibiotic prophylaxis (Malchau et al. 2002, Engesaeter et al. 2003). As theoretically the use of antibiotics should not have any influence on aseptic loosening, this suggests that the diagnosis of infection was inadequate. Under-diagnosis of infection in THA could possibly reduce the survival of revision hip implants.One of the major challenges when diagnosing low-grade infection is the accurate identification of microorganisms. These can be difficult to detect with routine diagnostics because of previous antimicrobial exposure or the requirement of certain microorganisms for specific nutrients, and also possibly due to reduced growth rates of biofilm-residing organisms (Fux et al. 2003, Schafer et al. 2008). To overcome this obstacle, new techniques for detection and identification of bacteria have been introduced. For example, polymerase chain reaction (PCR) on bacterial 16S ribosomal RNA (rRNA) can theoretically detect as little as 1 bacterium in a sample (Trampuz et al. 2003, Clarke et al. 2004, Fenollar et al. 2006, Kobayashi et al. 2009, Bergin et al. 2010). The apparent disadvantage of this feature is that PCR detection is susceptible to bacterial contamination (Panousis et al. 2005).Previously, our group developed and validated a combined 16S rRNA PCR and reverse line blot hybridization (RLBH) technique, which could identify many bacteria at the species level (Moojen et al. 2007). This combined technique was then used in a clinical study to test the hypothesis that there is under-diagnosis of infection in patients undergoing a THA revision due to aseptic loosening. In 7 Dutch hospitals, 176 patients undergoing revision of their THA following a preoperative diagnosis of aseptic loosening were included. During surgery, tissue biopsies were obtained for microbiological examination, pathological analysis, and broad-range 16S rRNA PCR with RLBH. We showed that 7 (4%) of these patients had a bacterial infection and an additional 15 (9%) were suspected of having an infection. Of these 22 patients, 2 were given a prolonged period of treatment with antibiotics. After a 1-year follow-up of 170 of the 176 patients, none of the 22 patients with an infection or suspected infection had undergone additional surgery.In the current study, we performed a mid- to long-term follow-up on this cohort to investigate the effects of missed low-grade infection on implant survival and clinical outcome. The hypothesis was that patients with an undiagnosed low-grade infection would show a higher rate of implant failure and poorer clinical outcome.     

Association between alcohol consumption and rotator cuff tear

Background and purpose — Long-term alcohol intake is associated with various negative effects on capillary microcirculation and tissue perfusion. We hypothesized that alcohol consumption might be a risk factor for both the occurrence and the severity of rotator cuff tears (RCTs).Patients and methods — A case-control study was performed. We studied 249 consecutive patients (139 men and 110 women; mean age 64 (54–78) years) who underwent arthroscopic rotator cuff repair. Tear size was determined intraoperatively. The control group had 356 subjects (186 men and 170 women; mean age 66 (58–82) years) with no RCT. All participants were questioned about their alcohol intake. Participants were divided into: (1) non-drinkers if they consumed less than 0.01 g of ethanol per day, and (2) moderate drinkers and (3) excessive drinkers if women (men) consumed > 24 g (36 g) per day for at least 2 years.Results — Total alcohol consumption, wine consumption, and duration of alcohol intake were higher in both men and women with RCT than in both men and women in the control group. Excessive alcohol consumption was found to be a risk factor for the occurrence of RCT in both sexes (men: OR = 1.7, 95% CI: 1.2–3.9; women: OR = 1.9, 95% CI: 0.94–4.1). Massive tears were associated with a higher intake of alcohol (especially wine) than smaller lesions.Interpretation — Long-term alcohol intake is a significant risk factor for the occurrence and severity of rotator cuff tear in both sexes.The supraspinatus and infraspinatus tendons have a hypovascularized portion approximately 15 mm in length at their insertion on the great tuberosity (Rothman et al. 1965, Blevins et al. 1997). Any systemic or local disease or life habit that can negatively influence the capillary microcirculation, such as arterial hypertension (Gumina et al. 2013), cardiopulmonary disease (Harryman et al. 2003), obesity (Gumina et al. 2014), smoking (Carbone et al. 2012), and hypercholesterolemia (Kim et al. 2000), can—from local hypoxia—lead to tendon degeneration and rupture (Benson et al. 2010).Many studies on humans and animals have shown that habitual high-dose intake of ethanol-containing beverages has various negative effects on capillary microcirculation and tissue perfusion (Liu et al. 2002, Fuchs 2005, Zilkens et al. 2005, Beilin and Puddey 2006, Costanzo et al. 2010, Wakabayashi 2011, Shirpoor et al. 2012).We therefore hypothesized that long-term intake of high doses of alcohol might be a risk factor for both the occurrence and the severity of rotator cuff tears (RCTs).     

Risk of re-admission,reoperation, and mortality within 90 days of total hip and knee arthroplasty in fast-track departments in Denmark from 2005 to 2011

Purpose

To compare the risks of re-admission, reoperation, and mortality within 90 days of surgery in orthopedic departments with well-documented fast-track arthroplasty programs with those in all other orthopedic departments in Denmark from 2005 to 2011.

Methods

We used the Danish hip and knee arthroplasty registers to identify patients with primary total hip arthroplasty or total knee arthroplasty. Information about re-admission, reoperation, and mortality within 90 days of surgery was obtained from administrative databases. The fast-track cohort consisted of 6 departments. The national comparison cohort consisted of all other orthopedic departments. Regression methods were used to calculate relative risk (RR) of adverse events, adjusting for age, sex, type of fixation, and comorbidity. Cohorts were divided into 3 time periods: 2005–2007, 2008–2009, and 2010–2011.

Results

79,098 arthroplasties were included: 17,284 in the fast-track cohort and 61,814 in the national cohort. Median length of stay (LOS) was less for the fast-track cohort in all 3 time periods (4, 3, and 3 days as opposed to 6, 4, and 3 days). RR of re-admission due to infection was higher in the fast-track cohort in 2005–2007 (1.3, 95% CI: 1.1–1.6) than in the national cohort in the same time period. This was mainly due to urinary tract infections. RR of re-admission due to a thromboembolic event was lower in the fast-track cohort in 2010–2011 (0.7, CI: 0.6–0.9) than in the national cohort in the same time period. No differences were seen in the risk of reoperation and mortality between the 2 cohorts during any time period.

Interpretation

The general reduction in LOS indicates that fast-track arthroplasty programs have been widely implemented in Denmark. At the same time, it appears that dedicated fast-track departments have been able to optimize the fast-track program further without any rise in re-admission, reoperation, and mortality rates.Even though the main principles of total hip arthroplasty (THA) and total knee arthroplasty (TKA) have been unchanged for years, the clinical pathways for patients have been changed in many respects during the past decade, to enhance recovery, reduce morbidity, increase patient satisfaction, and reduce length of stay (LOS). These principles—often known as fast-track surgical programs, enhanced recovery programs, or rapid recovery protocols (they are known by many names)—have been widely adopted today for THA and TKA in Denmark (Kehlet 2013).Clinical studies have shown that the risks of thromboembolic complications (Husted et al. 2010a) and mortality (Malviya et al. 2011) have become reduced in THA and TKA when comparing the same department before and after implementation of fast-track programs. Also, patient-related outcomes such as pain, quality of life (Larsen et al. 2008, Raphael et al. 2011, den Hertog et al. 2012), and patient satisfaction are positively associated with fast-track surgery (Larsen et al. 2008, Machin et al. 2013). Thus, the implementation of fast-track programs reduces LOS in patients who have undergone THA and TKA (Husted and Holm 2006, Larsen et al. 2008, Malviya et al. 2011, Raphael et al. 2011, den Hertog et al. 2012, Hartog et al. 2013). In Denmark, LOS for both THA and TKA was reduced from 10–11 days in 2000 to 4 days in 2009 (Husted et al. 2012), indicating a general trend towards use of fast-track surgery in most or all of the orthopedic departments in Denmark.Today, 10 Danish orthopedic departments, supported by the Lundbeck Foundation Center for Fast-track Hip and Knee Replacement, have described their fast-track programs and results in detail (www.fthk.dk, Kehlet and Søballe 2010, Husted et al. 2010b). A common denominator for these departments is their compliance to well-documented interdisciplinary logistic and clinical instructions— all of which are known to be significant factors for improved and accelerated recovery (Barberi et al. 2009, Bozic et al. 2010). We hypothesized that results regarding morbidity and mortality from the fast-track departments would be comparable to or even better than results from other departments that use standard, less systematically described treatment regimes after THA and TKA.We therefore investigated whether orthopedic departments with well-documented fast-track THA and TKA programs had lower short-term risk of re-admission, reoperation, and mortality than all other orthopedic departments in Denmark during different stages of implementation of the fast-track programs in the period 2005–2011.     

Metal-backed versus all-polyethylene tibial components in primary total knee arthroplasty

Background and purpose

The choice of either all-polyethylene (AP) tibial components or metal-backed (MB) tibial components in total knee arthroplasty (TKA) remains controversial. We therefore performed a meta-analysis and systematic review of randomized controlled trials that have evaluated MB and AP tibial components in primary TKA.

Methods

The search strategy included a computerized literature search (Medline, EMBASE, Scopus, and the Cochrane Central Register of Controlled Trials) and a manual search of major orthopedic journals. A meta-analysis and systematic review of randomized or quasi-randomized trials that compared the performance of tibial components in primary TKA was performed using a fixed or random effects model. We assessed the methodological quality of studies using Detsky quality scale.

Results

9 randomized controlled trials (RCTs) published between 2000 and 2009 met the inclusion quality standards for the systematic review. The mean standardized Detsky score was 14 (SD 3). We found that the frequency of radiolucent lines in the MB group was significantly higher than that in the AP group. There were no statistically significant differences between the MB and AP tibial components regarding component positioning, knee score, knee range of motion, quality of life, and postoperative complications.

Interpretation

Based on evidence obtained from this study, the AP tibial component was comparable with or better than the MB tibial component in TKA. However, high-quality RCTs are required to validate the results.The design of the tibial component is an important factor for implant failure in total knee arthroplasty (TKA) (Pagnano et al. 1999, Forster 2003, Gioe et al. 2007b, Willie et al. 2008, Garcia et al. 2009, KAT Trial Group 2009). The metal-backed (MB) design of tibial component has become predominant in TKA because it is thought to perform better than the all-polyethylene (AP) design (Muller et al. 2006, Gioe et al. 2006, 2007a,b). In theory, the MB tibial component reduces bending strains in the stem, reduces compressive stresses in the cement and cancellous bone beneath the baseplate (especially during asymmetric loading), and distributes load more evenly across the interface (Bartel et al. 1982, 1985, Taylor et al. 1998). However, critics of the MB tibial component claim that there are expensive implant costs, reduced polyethylene thickness with the same amount of bone resection, backside wear, and increased tensile stresses at the interface during eccentric loading (Bartel et al. 1982, 1985, Pomeroy et al. 2000, Rodriguez et al. 2001, Li et al. 2002, Muller et al. 2006, Blumenfeld and Scott 2010, Gioe and Maheshwari 2010).In the past decade, several randomized controlled trials (RCTs) have been performed to assess the effectiveness of the MB tibial component (Adalberth et al. 2000, 2001, Gioe and Bowman 2000, Norgren et al. 2004, Hyldahl et al. 2005a, b, Muller et al. 2006, Gioe et al. 2007, Bettinson et al. 2009, KAT Trial Group 2009). However, data have not been formally and systematically analyzed using quantitative methods in order to determine whether the MB tibial component is indeed optimal for patients in TKA. In this study, we wanted (1) to determine the scientific quality of published RCTs comparing the AP and MB tibial components in TKA using Detsky score (Detsky et al. 1992) and (2) to conduct a meta-analysis and systematic review of all published RCTs that have compared the effects of AP and MB tibial components on the radiographic and clinical outcomes of TKA.     

Antibiotic cement was associated with half the risk of re-revision in 1,154 aseptic revision total knee arthroplasties

ResultsThere were 114 re-revisions (10%) with a median time to reoperation of 3.6 years (interquartile range (IQR): 2.6–5.2). The infection rate was 2.9% (34/1,154) and accounted for 30% of re-revisions (34 of 114). In adjusted models, use of antibiotic-loaded cement was associated with a 50% lower risk of all-cause re-revision surgery (hazard ratio (HR) = 0.5, 95% CI: 0.3–0.9), age with a 20% lower risk for every 10-year increase (HR = 0.8, CI: 0.7–1.0), body mass index (BMI) with a 20% lower risk for every 5-unit increase (HR = 0.8, CI: 0.7–1.0), and a surgeon’s greater cumulative experience (≥ 20 cases vs. < 20 cases) with a 3 times higher risk of re-revision (HR = 2.8, CI: 1.5–5).InterpretationRevised TKAs were at high risk of subsequent failure. The use of antibiotic-loaded cement, higher age, and higher BMI were associated with lower risk of further revision whereas a higher degree of surgeon experience was associated with higher risk.ResultsThe study cohort consisted of 1,154 aseptic revision TKAs. The mean age of the cohort was 65 (SD 10) years old, 61% were female, 32% were diabetic, 64% were white, 28% had a BMI greater than 35, and 52% had an ASA score of < 3. (2006a, Mortazavi et al. 2011, Bae et al. 2013, Luque et al. 2014). Sierra et al. (2004) reported a 40% cumulative revision risk at 20 years in 1,814 cases operated over a 30-year period. The Finnish Arthroplasty Register reported 79% survivorship of revision TKA at 10 years in 2,637 revision TKAs (Sheng et al. 2006b). In a smaller and more recent study by Luque et al. (2014), 125 aseptic revisions were reported with a minimum follow-up of 7 years and an 8-year survival of 88%. The causes of revision in our cohort parallel those presented in other studies where infection, aseptic loosening, and pain due to instability or stiffness consistently remain the leading causes of revision (Sheng et al. 2006a, Mortazavi et al. 2011, Bae et al. 2013, Luque et al. 2014).We found that the use of antibiotic cement at the time of the index revision was associated with half the risk of future all-cause revision. In a recent randomized controlled trial, the effect of vancomycin-loaded cement use in the context of 183 low-risk, aseptic revision TKAs was evaluated and a statistically significant reduction in postoperative deep infections at a minimum follow-up of 36 months was reported (none in the intervention group became infected, as compared to 7% in the control group) (Chiu and Lin 2009). However, several studies that have evaluated the association between antibiotic-loaded cement and infection after primary TKA surgery have arrived at inconsistent results. A review did not find antibiotic-loaded cement to be consistently associated with a lower risk of infection in modern, primary TKA (Jiranek et al. 2006). Also, a study by Namba et al. (2013), using the same data source as in our study, found that—paradoxically—antibiotic-loaded cement was associated with a slightly higher risk of surgical site infection after TKA. The higher risk of infection in revision TKA than in primary TKA procedures is probably the reason why we identified such a substantially lower risk of re-revision surgery in cases where antibiotic-loaded cement was used. Furthermore, the use of antibiotic bone cement in cases of subclinical or undiagnosed infections might favorably affect the results of the procedure.A second factor, the surgeon’s cumulative experience at the time of the index revision, was associated with a higher risk of re-revision surgery. As the most complex and high-risk cases are referred to more experienced surgeons, we believe that this finding is probably a proxy for case complexity, which is something we could not adjust for in our analysis. To our knowledge, the finding that higher BMI was associated with a small but statistically significantly lower risk of revision has not been reported elsewhere with respect to outcomes of revision TKA surgery, while the decrease in risk with older age has (Sheng et al. 2006b). We can only infer that activity levels may be lower in older patients or in those with a higher BMI, and that a combination of higher morbidity, higher perceived risk, and lower demand may lead to a lower revision risk associated with increasing age (Sheng et al. 2006b).After adjusting for all other risk factors, we did not find sex, race, ASA score, diabetic status, surgeon volume, hospital volume, surgeon’s TJA fellowship training, or use of hinged prosthesis at index revision to be associated with the risk of re-revision surgery.Our study had several limitations and strengths. Among the limitations, some of the data sourced for this study required voluntary surgeon participation (currently at 95%) with non-differential rates of participation across sites. There were missing data, but they were handled in the statistical analysis using multiple imputations. We do not feel that either of these limitations would affect outcomes. In addition, due to our sample size, which limited by the number of factors that could be evaluated at this time, in our analysis we were not able to evaluate the influence of surgical factors such as fixation method (i.e. cemented, uncemented, or hybrid), the extent of the index revision (i.e. 1, 2, or more components revised) and structural issues such as bone quality. Doing this might identify other risk factors for early revision. Furthermore, our decision to limit the cohort to those patients for whom the primary procedure had been captured in the registry limited us to a short follow-up period. Longer follow-up might have shown a higher percentage of patients revised for component wear or loosening. It is also likely that, as with any study of revision TKA, some patients in the cohort may have had an undiagnosed low-grade infection and that this might have skewed the overall risk of infection. Regarding surgeon experience, we note that the results can only reflect the period of data collection for the study and not lifetime experience.Among the strengths of the present study, we can include the large number of cases treated across multiple medical centers in a community-based setting, which should have provided data comparable to the experience of the majority of community surgeons. Furthermore, there was only a small possibility of data-handling bias due to the use of our integrated electronic medical record. Additionally, all of the outcomes evaluated in this study were manually adjudicated by a trained research assistant to guarantee the accuracy and integrity of the information reported, thus ensuring the high internal validity of the information reported.In summary, the most striking finding from our study of 1,154 aseptic TKA revisions is that the use of antibiotic-loaded cement was associated with half the risk of subsequent revision surgery. Infection, instability, pain, and aseptic loosening remain ongoing challenges associated with a 20% cumulative probability of failure at 5 years. Surgeons and patients alike must be cognizant of the potential for poor long-term outcomes following revision TKA.All the authors contributed to the study design and contributed substantially to collecting the data, interpreting the results, drafting the article, and to revision. PHC and MCSI conducted the statistical analysis.No competing interests declared.     

Association between maternal age at conception and risk of idiopathic clubfoot: A meta-analysis

MethodsWe searched PubMed-MEDLINE, EMBASE, and the Cochrane Library up to June 2015 and supplemented the search with manual searches of the reference lists of the articles identified. 11 studies published between 1990 and 2015 were pooled. We investigated heterogeneity in maternal age and whether publication bias might have affected the results.ResultsCompared to a control group, maternal age at conception of between 20 and 24 years old was associated with an increased risk of occurrence of clubfoot (OR = 1.2, 95% CI: 1.1–1.4). No such association was found for the age groups of ≥ 35, 30–34, 25–29, and < 20 years. There was no heterogeneity in the age groups of ≥ 35, 30–34, and 20–24 years, moderate heterogeneity in the 25- to 29-year age group, and a large degree of heterogeneity in the group that was < 20 years of age. The prediction intervals for the age groups of 25–29 and < 20 years were 0.56 to 1.3 and −0.39 to 2.4, respectively. We found no evidence of significant publication bias.InterpretationFrom the results of this meta-analysis of 11 studies, maternal age at conception between 20 to 24 years of age appears to be associated with an increased risk of occurrence of clubfoot.StatisticsFor the studies included, we determined the pooled OR with 95% confidence interval (CI) for the maternal age groups versus control groups. Statistical heterogeneity was evaluated with the I2 statistic (Higgins and Thompson 2002): I² > 50% was considered statistically significant (Hedges and Pigott 2001). Here, we chose a random effects model to calculate the pooled OR and CI for more conservative results. If there was a moderate or large degree of heterogeneity between the studies included (with I² > 25% as a guide (Higgins et al. 2003)), we calculated a prediction interval considering the potential effect within an individual study setting (Riley et al. 2011). We used visual inspection of funnel plots, Egger’s test, and Begg’s test to determine whether publication bias might have affected the statistical results (Begg et al. 1994, Egger and Smith 1998). All statistical analyses were conducted using Revman 5.3.5 (The Nordic Cochrane Centre, Copenhagen, Denmark) and Stata 12.0. Any p-value of < 0.05 was considered statistically significant.DiscussionWhether or not maternal age is associated with the risk of clubfoot has been unlear. A recent population-based case-matched control study in Hungary from Csermely et al. (2015) showed a higher proportion of cases of clubfoot in offspring of mothers in the youngest age group (≤ 19 years), and a borderline excess of cases in offspring of mothers of older age (i.e. ≥ 35 years). Palma et al. (2013) reported an association between maternal age (of < 23 years) at conception and increased risk of clubfoot. Parker et al. (2009) also found that maternal age (of < 23 years) was associated with clubfoot. Similarly, a study by Nguyen et al. (2012) showed that young maternal age (of < 25 years old) was associated with increased risk of clubfoot. Dickinson et al. (2008) found a trend of increasing risk of clubfoot with decreasing maternal age, with women in the youngest age group (< 20 years) having the highest risk (OR = 1.6, 95% CI: 1.1–2.2) relative to women aged 30 or more. Multivariate analysis by Mahan et al. (2014) revealed that the strongest predictor in prenatal detection was a maternal age of ≥ 35 years (OR = 3.5). 1 study showed a negative correlation between occurrence of clubfoot and maternal age of > 35 years (Kancherla et al. 2010). Hollier et al. (2000) reported a higher risk of clubfoot, diaphragmatic hernia, and cardiac defects in mothers of older age. However, the opposite results—with no association between maternal age at conception and risk of clubfoot—have also been reported (Alderman et al. 1991, Cardy et al. 2007, Cardy et al. 2011, Honein et al. 2000, Moorthi et al. 2005, Sahin et al. 2013).The findings from this meta-analysis of 11 case-control studies were that a maternal age of 20–24 years old at conception was statistically significantly associated with increased incidence of clubfoot. There was a 20% higher risk of clubfoot than in the control group. We found no evidence that other maternal age groups were associated with an increased risk of clubfoot. We found no heterogeneity in maternal age groups of 35 years or more, 30–34 years, or 20–24 years, moderate heterogeneity in the 25- to 29-year age group, and a large degree of heterogeneity in the age group of less than 20 years. The prediction intervals for the age groups of 25–29 years and less than 20 years both overlapped the OR value of 1. After sensitivity analysis of these groups, the same results were observed, indicating that our meta-analysis was relatively stable. The source of heterogeneity in these 2 maternal age groups might be traced to different survey regions, racial variation, and confounding factors.A strength of our meta-analysis was the large number of cases included (n = 15,242 in the clubfoot group and 97,041 in the control group). One limitation might be the possible effects of having only a small number of studies, as only 11 studies were included. We did not find any publication bias because of such effects, but Egger’s test is known to have low power when less than 20 studies are included in a meta-analysis (Sterne et al. 2000). By not adequately controlling for confounders, our findings may have been biased in either direction (i.e. an exaggeration or underestimation of the risk estimate).A large degree of heterogeneity was found for the maternal age group of less than 20 years (I² = 74%), but we did not conduct a subgroup analysis using the limited information from crude data provided by the studies included.The risk of clubfoot may be attributed to sociodemographic factors, socioeconomic status, education status, social culture, and other factors. A possible explanation of why a maternal age of between 20 and 24 years of age would be associated with an increased incidence of clubfoot might be the first-born baby boom period in this age group. Epidemiological studies have consistently found a higher prevalence of idiopathic clubfoot in primiparous mothers (Honein et al. 2000, Skelly et al. 2002, Carey et al. 2005). Our meta-analysis suggests that there may be a negative correlation between the risk of clubfoot and higher maternal age. The reason may be attributed to the birth of another baby in a family, which leads to a decreased clubfoot risk at 25 or older years of maternal age. It has been suggested that the higher the parity of a pregnant woman, the lower the risk of clubfoot in the baby (Carey et al. 2005, Dickinson et al. 2008, Kancherla et al. 2010). The low risk of congenital clubfoot in mothers less than 20 years old may be explained by the higher incidence of abortion and miscarriage in this age group.

Supplementary data

Tables 1 and 2 and Figure 2 are available on Acta’s website (www.actaorthop.org), identification number 9564.YBL and JD contributed substantially to the acquisition of data and drafted the article. JZ and ZKW analyzed and interpreted the extracted data. LZ contributed to the conception and design of the article. HL and XY conducted the literature review and extracted the data from the studies that were included. CLX was responsible for statistical testing.No competing interests declared.     

Fast-track revision knee arthroplasty. A feasibility study

Background and purpose

Fast-track surgery has reduced the length of hospital stay (LOS), morbidity, and convalescence in primary hip and knee arthroplasty (TKA). We assessed whether patients undergoing revision TKA for non-septic indications might also benefit from fast-track surgery.

Methods

29 patients were operated with 30 revision arthroplasties. Median age was 67 (34–84) years. All patients followed a standardized fast-track set-up designed for primary TKA. We determined the outcome regarding LOS, morbidity, mortality, and satisfaction.

Results

Median LOS was 2 (1–4) days excluding 1 patient, who was transferred to another hospital for logistical reasons (10 days). None of the patients died within 3 months, and 3 patients were re-admitted (2 for suspicion of DVT, which was not found, and 1 for joint mobilization). Patient satisfaction was high.

Interpretation

Patients undergoing revision TKA for non-septic reasons may be included in fast-track protocols. Outcome appears to be similar to that of primary TKA regarding LOS, morbidity, and satisfaction. Our findings call for larger confirmatory studies and studies involving other indications (revision THA, 1-stage septic revisions).For more than a decade, favorable outcomes following fast-track protocols rather than more conventional hospital stays have been reported from numerous studies on primary THA and TKA. In the last few years, outcomes have been further improved, mainly due to improved multimodal opioid-sparing analgesia and early mobilization, allowing patients to fulfill functional discharge criteria within 2–3 days (Husted et al. 2008, 2010 a,b,c,d, Larsen et al. 2008 a,b,c, 2009, Andersen et al. 2009, Barbieri et al. 2009, Rotter et al. 2010). The addition of local infiltration analgesia (LIA) has improved early analgesia and facilitated early recovery, allowing patients to ambulate with full weight bearing within 2–3 hours of surgery (Andersen et al. 2008 a,b, 2009, Holm et al. 2010).So far, however, no one has reported the potential benefits of the fast-track methodology (including multimodal opioid-sparing analgesia, perioperative LIA, and early mobilization) for revision TKA, with its more extensive surgical trauma leading to a corresponding increase in the surgical stress responses. We therefore investigated the feasibility of our well-documented fast-track primary TKA program on a consecutive cohort of revision TKA patients.     

High-volume infiltration analgesia in bilateral hip arthroplasty. A randomized, double-blind placebo-controlled trial

Background and purpose

High-volume infiltration analgesia may be effective in postoperative pain management after hip arthroplasty but methodological problems prevent exact interpretation of previous studies.

Methods

In a randomized, double-blind placebo-controlled trial in 12 patients undergoing bilateral total hip arthroplasty (THA) in a fast-track setting, saline or high-volume (170 mL) ropivacaine (0.2%) with epinephrine (1:100,000) was administered to the wound intraoperatively along with supplementary postoperative injections via an intraarticular epidural catheter. Oral analgesia was instituted preoperatively with a multimodal regimen (gabapentin, celecoxib, and acetaminophen). Pain was assessed repeatedly for 48 hours postoperatively, at rest and with 45° hip flexion.

Results

Pain scores were low and similar between ropivacaine and saline administration. Median hospital stay was 4 (range 2–7) days.

Interpretation

Intraoperative high-volume infiltration with 0.2% ropivacaine with repeated intraarticular injections postoperatively may not give a clinically relevant analgesic effect in THA when combined with a multimodal oral analgesic regimen with gabapentin, celecoxib, and acetaminophen.Continuous epidural analgesia (Choi et al. 2003) or continuous or single-shot peripheral nerve blocks (Boezaart 2006, Ilfeld et al. 2008) may provide sufficient analgesia after total hip arthroplasty (THA), but both techniques are associated with potential motor blockade, thereby hindering early rehabilitation (Choi et al 2003, Boezaart 2006, Ilfeld et al. 2008).Local infiltration analgesia (LIA) (Röstlund and Kehlet 2007, Kerr and Kohan 2008, Otte et al. 2008) with intraoperative infiltration of local anesthetic in the surgical wound and subsequent supplementary postoperative intraarticular or wound injections has been reported to be effective in knee arthroplasty (Andersen et al. 2008). However, for THA only limited and inconclusive data are available from placebo-controlled and randomized trials (Bianconi et al. 2003, Andersen et al. 2007 a, b, Busch et al. 2010) and from non-randomized cohort studies (Kerr and Kohan 2008, Otte et al. 2008). We therefore decided to evaluate the analgesic efficacy of LIA in a placebo-controlled, randomized and double-blind trial in fast-track bilateral hip arthroplasty with administration of either ropivacaine or saline to the wound, thereby limiting the large inter-individual pain response to THA. This design has proven valid in assessing the analgesic value of LIA in TKA (Andersen et al. 2008). The primary endpoint was pain on flexion of the hip joint 8 hours postoperatively.