UCLA Activity Score Research Articles

FAI SURGERY IN THE ADOLESCENT POPULATION: MILD DEFORMITIES AND LACK OF SPORTS PARTICIPATION ARE ASSOCIATED WITH AN INCREASED RISK OF TREATMENT FAILURE

Background: Femoroacetabular impingement (FAI) is as prevalent in adolescents as in adults, yet few studies have analyzed treatment outcomes in the adolescent population. The purpose of this study was to determine the clinical outcomes of FAI surgery in adolescent patients and to identify predictors of treatment failure. Methods: A cohort of 126 adolescent patients (<18 years) undergoing surgery for symptomatic FAI were prospectively assessed among a larger multicenter cohort. The adolescent subgroup included 74 (58.7%) males and 52 (41.3%) females, had a mean age of 16.1 years (range 11.3-18.0), and a mean follow-up of 3.7 years. Mild cam FAI was defined by an alpha angle less than 55 degrees. Clinical outcomes were analyzed with the mHHS, HOOS (5 domains), and UCLA activity score. Failure was defined as revision surgery or clinical failure (failure to reach MCID (minimally clinically important difference) or PASS (patient acceptable symptoms state) for modified Harris Hip score. Statistical analysis was performed to identify factors significantly associated with failure. Results: There was clinically important improvement in all PROs (mHHS, all HOOS domains) for the overall cohort and 81% of patients met criteria for a successful outcome. The failure rate (revision surgery or clinical failure) of the overall cohort was 19%, including revision surgery in 8.7%. Female patients were significantly more likely than male patients to be classified as a failure (25.7% vs. 9.1%, p=0.017, OR 2.6), in part because of a lower preoperative mHHS (59.1 vs. 67.0, p<0.001). Mild cam FAI (alpha less than 55 degrees) was present in 31.5% of cases including 39.1% of females and 14.5% of males. Maximal alpha angle was significantly inversely associated with the failure rate (37.5% for alpha<55, 19.2% for alpha 55-63, and 6.8% for alpha>63, p<0.005). Non-athletes were at a significantly greater risk of failure compared to athletes (26.5% vs. 10.3%, p=0.043, OR 2.3). Multivariable logistic regression identified mild cam FAI and lack of participation in sports as predictive of failure (p=0.005 and p=0.04), while gender was no longer significantly associated with failure after controlling for other variables. Conclusions: Adolescent patients undergoing surgical treatment of FAI demonstrate significant improvement at early followup. However, mild cam FAI deformities (which are common in adolescent female patients) and lack of participation in sports are independently associated with higher rates of treatment failure. These factors associated with treatment failure should be considered in surgical treatment decision-making and patient counseling.

Gender and Preoperative Function Predict Physical Activity Levels After Revision Total Knee Arthroplasty

BackgroundThe incidence of revision total knee arthroplasty (TKA) is projected to increase 6-fold worldwide by 2030. As the number of younger, physically active revision TKA patients increases in future, understanding factors influencing postoperative function will be increasingly important to help counsel patients. The primary aim of this study was to examine factors influencing return to physical activity following revision TKA. MethodsPatients who had undergone tibiofemoral revision between 2003 and 2013 at a single UK teaching hospital were retrospectively identified from a prospectively collected arthroplasty database. Preoperative activity level (University of California, Los Angeles [UCLA] score), patient demographics, indication, implant used, and Oxford Knee Scores (OKSs) were recorded in the database. At a mean follow-up of 3.9 years (standard deviation, 2.2), UCLA score, OKS, EuroQol-5 Dimension Score (EQ-5D), satisfaction, complications, and WORQ scores (Work, Osteoarthritis and Joint-Replacement Questionnaire) were sampled via postal questionnaire. Patient experience of complications and related surgery was also identified from healthcare records. Univariate and multivariate analyses were performed. ResultsResponses were received from 112 revision TKAs (112 patients; mean age, 71 years). Mean UCLA activity scores improved from preoperative levels (P < .001): activity levels improved in 47% of patients with 58% engaging in moderate or more intensive activities (UCLA score ≥5). Postoperative activity level was independently predicted by male gender (P = .042) and preoperative UCLA score (P < .001). Increasing social deprivation was associated with inferior UCLA (P = .005), EQ-5D (P < .005), and OKS (P = .006) scores. Indication, implant type, and patient body mass index did not affect functional outcome or satisfaction (P > .05). Patients <65 years old were more likely to be dissatisfied (P = .009), and patients aged ≤55 years were more likely to report difficulties with WORQ criteria (P < .05). ConclusionAlthough 90% of patients maintain activity levels following revision TKA, less than half increase levels and this is predicted by male sex and pre-revision activity level.

Return to activity following revision total hip arthroplasty.

Demand for revision total hip arthroplasty (RTHA) continues to grow worldwide and is expected to more than double within the next 1-2 decades. The primary aim of this study was to examine return to function following revision THA in a UK population. We assessed 118 patients (132 RTHAs, mean age 65years SD 13, range 23-88) at a mean follow-up of 7.9years (SD 4.4) postoperatively. Preoperative age, gender, BMI, social deprivation, operative indication, comorbidities, activity level (UCLA score) and Oxford Hip Scores (OHS) were recorded. Postoperative UCLA score, OHS, EQ-5D, satisfaction levels and performance in activities of daily living (ADLs) were obtained and univariate and multivariate analysis performed. Mean UCLA activity score improved following RTHA (p < 0.001): UCLA activity score improved in 37% and was unchanged in 50%; 49% of patients engaged in at least moderate level activities (UCLA score ≥ 6). Patient BMI, gender, age and reason for revision did not influence levels of pain, stiffness or activity at follow-up. Preoperative UCLA activity scores (p < 0.001) independently predicted long-term UCLA scores. Independent predictors (p < 0.05) of poor hip-specific function (OHS) following revision included social deprivation, revision for periprosthetic fracture and lower preoperative OHS. Difficulties with ADLs were associated with increasing deprivation, ≥ 3 comorbidities, and revision for periprosthetic fracture or infection (p < 0.05). Overall, 79% of patients remained satisfied or very satisfied following revision THA. Following RTHA, 10% suffered a dislocation and 13% required reoperation for complications. Revision THA facilitates long-term return to preoperative levels of physical activity in the majority of patients, though activity levels increase in one-third only. Overall over three-quarters are satisfied with their outcome, but revision for periprosthetic fracture or dislocation gives the worse overall outcomes and lower satisfaction levels.

Predictors of return to desired activity 12 months following unicompartmental and total knee arthroplasty

Background and purpose — 1 in 5 patients are dissatisfied following unicompartmental or total knee arthroplasty (UKA or TKA). This may be partly explained by failing to return to desired activity post-arthroplasty. To facilitate return to desired activity, a greater understanding of predictors of return to desired activity in UKA and TKA patients is needed. We compared rates of return to desired activity 12 months following UKA vs. TKA, and identified and compared predictors of return to desired activity 12 months following UKA vs. TKA.Patients and methods — Patients were prospectively recruited from 2 hospitals prior to undergoing UKA or primary TKA. Patients reported preoperatively the activity/activities that were limited due to their knee that they wished to return to after arthroplasty. At 12-months postoperatively, patients reported whether they had returned to these activities (‘return to desired activity’). Preoperative predictors evaluated were age, sex, BMI, education, comorbidities, pain expectations, Oxford Knee Score (OKS), UCLA Activity Score, and EQ-5D. Generalized linear models assessed the relationship between potential predictors and return-to-desired-activity.Results — The response rate of all patients eligible for 12-month follow-up was 74%. TKA patients (n = 575) were older (mean (SD) 70 (9) vs. 67 (10)) with a greater BMI (31 (6) vs. 30 (5)) than patients undergoing UKA (n = 420). 75% of UKA and 59% of TKA patients returned to desired activity. TKA patients had a greater risk of non-return to desired activity than patients undergoing UKA (risk ratio (95% CI) 1.5 (1.2–1.8)). Predictors of non-return to desired activity following UKA were worse OKS (0.96 (0.93–0.99)), higher BMI (1.04 (1.01–1.08)), and worse expectations (1.9 (1.2–2.8)). Predictors of non-return to desired activity following TKA were worse EQ-5D (0.53 (0.33–0.85)) and worse OKS (0.98 (0.96–1.0)).Interpretation — UKA patients were more likely to return to desired activity than TKA patients. Predictors of return to desired activity differed following UKA and TKA. Optimizing selection of arthroplasty procedure based on patient characteristics and targeting predictors of poor outcome may facilitate return to desired activity with potential to enhance postoperative satisfaction.

Are Complications After the Bernese Periacetabular Osteotomy Associated With Subsequent Outcomes Scores?

The Bernese periacetabular osteotomy (PAO) continues to be a commonly performed nonarthroplasty option to treat acetabular dysplasia, but only a few short-term studies have evaluated complications rigorously after PAO. (1) What complications are observed at 10-year mean followup of the Bernese PAO in patients with symptomatic acetabular dysplasia? (2) What factors are associated with these complications? (3) Do these complications affect clinical outcome scores? We reviewed 238 hips in 206 patients treated with PAO from July 1994 to August 2008. Only PAOs performed for symptomatic acetabular dysplasia and those that had at a minimum 4-year followup were included. Patients who went on to THA before 4 years were included in the study. Patients with hip pain who presented with a clinical presentation of symptomatic acetabular dysplasia, radiographic evidence of femoral head uncovering, and a lateral center-edge angle < 25° were considered for PAO and no other juxtaacetabular osteotomy was offered other than PAO. Sixty-two hips had diagnoses other than acetabular dysplasia and 22 were lost to followup. The remaining 154 hips (129 patients) were evaluated by chart review at a mean of 10 years (range, 1.7-20.5 years) using the UCLA Activity Score, modified Harris hip score (mHHS), WOMAC, and radiographic analysis. The mean age at PAO was 26 years (range, 10-60 years) and consisted of 113 female patients (132 hips [86%]) and 16 male patients (22 hips [14%]). Complications were graded using the validated Clavien-Dindo system. Complications were assessed for each hip and the highest complication grade was assigned to the hip if multiple complications occurred. We divided complication grades into three groups for analysis: no complications, Grade 1 complications, and complications that deviated from the standard postoperative course (Grades 2, 3, and 4). There were no Grade 5 complications. Variables with significant (p < 0.05) univariable associations with complications were considered for inclusion in a multivariable model. Outcome variables (mHHS and WOMAC) at the most recent followup visit were analyzed using a generalized estimating equation approach. Analysis of variance was used to compare UCLA at the most recent followup among the complication classes. Major complications defined as Clavien-Dindo Grade 3/4 occurred in 14 hips (9%). After controlling for potential confounding variables, we found that increasing body mass index (BMI) (odds ratio [OR], 1.16; 95% confidence interval, 1.05-1.25; p = 0.004) was associated with increased risk of complication. In contrast, greater surgeon experience was associated with a decreased risk (OR, 0.3; p = 0.002). Complications were associated with postoperative pain and activity, WOMAC (mean ± SD: 0 complications = 1.5 ± 15.1, 1 complication = 4.3 ± 4.1, 2-3 complications = 3.8 ± 4.6; p = 0.020) and UCLA scores (mean ± SD: 0 complications = 7.8 ± 2, 1 complication = 6.7 ± 2.1, 2-3 complications = 6.5 ± 2; p = 0.003). Most hips undergoing PAO have few complications. The most common major surgical complication is nonunion. Increasing BMI was a predictor of having a complication, and surgeon experience decreased complication risk. Having a complication adversely affected long-term pain and activity. To minimize complications and maximize outcomes, a patient's BMI should be assessed preoperatively and those with excessive BMI should be counseled on the increased risk of complications. In an experienced surgeon's hands, PAO has few complications at mean 10-year followup and a low risk of permanent disability. Level III, therapeutic study.

Previous failed hip arthroscopy negatively impacts early patient-reported outcomes of the periacetabular osteotomy: an ANCHOR Matched Cohort Study.

ABSTRACTSurgical treatment of hip dysplasia by arthroscopic procedures remains controversial. The aim of this study was to compare outcomes of periacetabular osteotomy (PAO) after failed hip arthroscopy to a matched-control group without previous arthroscopy. Fifty-two patients who underwent PAO after failed hip arthroscopy were matched to two subjects without arthroscopy based on age, sex, BMI and radiographic severity. Pre- and post-operative patient self-reported outcomes and radiographic parameters were compared at minimum 1-year follow-up. Prior to PAO the failed hip arthroscopy group exhibited lower modified Harris hip scores (mHHS; 57 versus 62; P = 0.04), WOMAC (59.9 versus 66.3; P = 0.08), UCLA activity (5 versus 7; P = 0.001) and SF12 physical scores (34 versus 40; P = 0.001) compared with the non-arthroscopy group. At minimum 1-year follow-up, the failed hip arthroscopy group had lower mHHS (78 versus 87; P = 0.003); worse WOMAC (84.1 versus 90.8; P = 0.02) and SF-12 physical component (46 versus 50; P = 0.02) with similar UCLA (7 versus 8; P = 0.21) compared with the non-arthroscopy group. No differences were detected regarding radiographic parameters or in patient-reported outcomes from preoperative to follow up. PAO achieved the desired radiographic correction and significant improvement in pain and function after a failed previous hip arthroscopy, however, the patient-reported outcomes were inferior to those of PAO without previous failed arthroscopy.

Periacetabular Osteotomy Improves Pain and Function in Patients With Lateral Center-edge Angle Between 18° and 25°, but Are These Hips Really Borderline Dysplastic?

AbstractBackgroundThe treatment of mild or borderline acetabular dysplasia is controversial with surgical options including both arthroscopic labral repair with capsular closure or plication and periacetabular osteotomy (PAO). The degree to which improvements in pain and function might be achieved u

Higher patient activity level and subchondral stiffening in asymptomatic cam femoroacetabular impingement subjects.

ABSTRACTA cam deformity is proposed as a cause of idiopathic osteoarthritis. Increased subchondral bone mineral density (BMD) is associated with this degenerative process of osteoarthritis, and the patient’s activity level may contribute to it. Therefore, the correlation between activity level and subchondral BMD in subjects with cam deformity FAI was studied. In this study, 26 asymptomatic cam deformity subjects (Bump) were compared with 18 subjects with a normal alpha angle (Control). Anterosuperior subchondral femoral neck and acetabular rim BMD were measured using quantitative computed tomography. Activity level was determined using the UCLA activity score. The correlation between BMD and UCLA activity were analysed. The result was a significantly higher BMD for Bump subjects in almost all measured sections. The UCLA score of the Bump versus Control subjects were comparable (8.96 versus 8.77, P = 0.740). While the controls showed no correlation between UCLA and BMD, a positive correlation was found for the Bump subjects on several femoral and acetabular impingement locations. These results support the conclusion that mechanical loading causes subchondral stiffening at the anterosuperior head–neck junction of the femur and anterosuperior acetabular rim. The absence of a correlation between BMD versus UCLA in the Controls supports the hypothesis that activity level may serve as a predictor for higher subchondral BMD in a cam deformity hip joint.

An evaluation of proximal femur bone density in young, active patients undergoing total hip arthroplasty at one year postoperatively.

Background:Prior investigations have shown a decrease in periprosthetic bone mineral density (BMD) of the calcar following total hip arthroplasty (THA). The purpose of this investigation was to study proximal femur BMD in a cohort of young, active patients following THA at 1 year postoperatively using a recently introduced stem design.Methods:This was a prospective, IRB-approved investigation of patients with an age <65 years, BMI <35 kg/m2, and presymptomatic UCLA score of >6 undergoing a primary THA for a diagnosis of osteoarthritis. All patients received a titanium, proximally coated, tapered cementless femoral stem (ACCOLADE II, Stryker Inc, Mahwah, NJ, USA). Dual energy X-ray absorptiometry scans were performed at 6 weeks, 6 months, and 1 year postoperatively. Bone density was analyzed for 7 traditional Gruen zones with BMD ratios calculated for change in BMD compared with the baseline.Results:31 patients (mean age of 52.6 + 6.5 years, BMI of 27.9 + 3.9 kg/m2, and UCLA activity score of 7.3 + 1.9) were included. The mean BMD ratio decreased at the 6 months and 1 year interval in zones 1 and 2. However, the mean BMD ratio was maintained in Gruen zones 3 thru 7 with zone 7 (medial calcar) demonstrating 100% maintenance of the baseline BMD at 1 year.Conclusion:This study demonstrates the maintenance of medial calcar bone density at 1 year postoperatively in young, active patients undergoing THA. Further longitudinal analysis of this stem design is necessary to elucidate the significance of this finding.

Hip morphology and patient factors associated with severity of hip symptoms in femoroacetabular impingement

Purpose: Femoroacetabular impingement (FAI) syndrome is a clinical disorder of the hip associated with pain and dysfunction, thought to be a precursor to hip osteoarthritis (OA). Several interacting anatomical parameters have been linked to the pathomechanism of FAI, including the alpha angle (αA), beta angle (βA), lateral centre edge angle (LCEA), acetabular version, femoral version, and femoral neck shaft angle (FNSA). Previous investigations of anatomical parameters and hip symptoms in FAI cohorts have primarily used plain radiographs, which permit only single-planar representation of the complex morphology of the femoral head and acetabulum, limiting analysis to the sub-region profiled. MRI provides multiplanar morphologic assessment without the use of ionizing radiation, with potential for post-processing of volumetric sequences to provide comprehensive, multi-planar consideration of αA, βA, femoral and acetabular version. We sought to study the relationship between symptom severity, morphological parameters and patient-level factors in FAI. Methods: Eighty-nine participants were diagnosed with FAI syndrome in a clinical setting by an orthopaedic surgeon. Age, gender, body mass index, nature of onset (gradual vs sudden) and duration of symptoms were recorded. Participants completed the international Hip Outcome Tool-33 (iHOT-33), a measure of hip health-related quality of life (QOL) (0 = worst possible QOL, 100 = best possible QOL), and the 10-point modified UCLA activity score (1 = “regular participation in impact sports”, 10 = “wholly inactive and dependent on others”). Participants received standardized plain radiographs and hip MRI scans on one of two 3T scanners (Siemens Prisma & Skyra). On a subset of 60 participant scans (41 cam-type, 3 pincer-type, 16 mixed-type FAI), αA was measured in four reconstructed radial planes at 30-degree intervals from superior to anterior (Fig. 1). The βA, defined as the angle formed by the αA vector and a line joining the centre of the femoral head to the acetabular rim, was also measured in these four planes. Femoral version was measured using axial hip and knee MRI sequences. Acetabular version was measured at 1cm inferior to the acetabular sourcil, using axial hip MRI sequences with the bi-ischial line as a reference point. LCEA and FNSA were measured on an AP pelvis X-ray. Statistical analyses included Pearson’s linear regressions and students' t-tests. Results: The 89 participants (32.9 ± 10.7 yrs, 40% female) had a mean iHOT-33 score of 41.0 ± 18.3. Modified UCLA activity scores and iHOT-33 scores were significantly associated (r = −0.351, P = 0.001), suggesting that more activity lends itself to better hip health-related QOL. Higher participant activity levels were also associated with a shorter duration of symptoms (r = 0.361, P = 0.001). No other patient factors were related to iHOT-33 score. The only anatomical parameter significantly associated with iHOT-33 score was the αA in the anterosuperior radial plane (r = −0.297, P = 0.025) (Table 1). Those with larger αAs (>75 degrees, n = 13) had significantly lower iHOT-33 scores than those with smaller αAs ( 75 degrees) and smaller αAs (<75 degrees) in any other radial plane, including for the maximum αA measured for each hip. Conclusions: Alpha angle in the anterosuperior radial plane was associated with hip health-related QOL, whereas other anatomical parameters, including αA measured in other radial planes, were not. Clinically, this finding supports the need for αA measurement at the anterosuperior radial plane in FAI diagnosis, and potentially highlights the importance of bony surgical correction at this region. Previous research has identified the anterosuperior region as particularly susceptible to chondrolabral damage in FAI; our study's findings link this structural damage to the presence of symptoms in FAI.

Letter to the Editor: No Difference Between Trabecular Metal Cones and Femoral Head Allografts in Revision TKA: Minimum 5-year Followup

To the Editor, We read the article by Sandiford and colleagues [3] with great interest. Although this is a valuable study, we have some queries for the authors. In the Patients and Methods section, the authors noted that 45 TKA revisions were performed using augmentation of host bone. Of those 45, surgeons used “femoral head allograft in 30 (75%) and trabecular metal cones in 15 (25%).” Shouldn’t the percentages be 66.7% and 33.3%, respectively? In the Trabecular Metal Cone Technique section, the authors stated: “Nine Type 2A and two Type 2B femoral defects and 13 Type 2A and six Type 2B tibial defects were treated with femoral head allografts. Four Type 2B and two Type 3 femoral defects and two Type 2A and seven Type 2B tibial defects were treated using trabecular metal cones.” However, the second sentence does not match up with the data in Table 1. Are the data in the text or in Table 1 correct? In the Conclusions section, the authors state that both techniques are viable options for the management of Anderson Orthopaedic Research Institute (AORI) Type 2 and 3 defects. But in the study, no patients with Type 3 bone defects were treated with femoral head allografts. Because of this, we believe that that the study’s conclusions may be overstated as published. Finally, the authors used the Oxford Knee Score, WOMAC, SF-12, and the UCLA activity score to assess knee function and quality of life, and additionally, radiographs were assessed for signs of loosening. But radiostereometric analysis (RSA) is also important because the AORI classification referenced in the article is based on radiological images. In fact, in a study by Jensen and colleagues [2], the difference between the mean maximum total point motion of the trabecular metal cone group and the no trabecular metal cone group was almost 2 mm, but they could not detect this as a significant difference. However, in Sandiford and colleagues, perhaps there is a significant difference between the trabecular metal cone and femoral head allograft groups. If Sandiford and colleagues compared outcomes of the two groups’ images at 3 weeks, 6 weeks, 3 months, and 1 year using RSA [1], and then annually after 1 year, using the methods they used, perhaps their conclusions would have been more convincing.

Cementless unicompartmental knee replacement allows early return to normal activity

BackgroundPhysical activity and regular participation in recreational sports gain importance in patients’ lifestyle after knee arthroplasty. Cementless unicompartimental Knee replacement with the Oxford System has been introduced into clinical routine. Currently there is no data reporting on the physical activity, return to sports rate and quality of live after medial cementless Oxford Unicompartimental Knee Replacement (OUKR).MethodsThis retrospective cohort study reports on the functional outcome of the first 27 consecutive patients (30 knees) that were consecutively treated with a cementless medial OUKR between 2007 and 2009 in our hospital. Physical activity and quality of life were measured using the Tegner-Score, the UCLA-Activity Score, the Schulthess Clinical Activity Questionnaire and the SF-36 Score. The patients’ satisfaction with the outcome was measured using a visual analogue scale.ResultsMean age at surgery was 62.5 years. Patients showed a rapid recovery with 17 out of 27 patients returning to sports within 3 months, 24 within 6 months after surgery. The Return-to-activity-rate was 100%. 10 out of 27 patients showed a high activity level (UCLA ≥7 points) with a mean postoperative UCLA-Score of 6.1 points.ConclusionsPatients recover rapidly after cementless OUKR with a return to sports rate of 100% and patients are able to participate in high impact sports disciplines.

2017 Chitranjan S. Ranawat Award: Does Computer Navigation in Knee Arthroplasty Improve Functional Outcomes in Young Patients? A Randomized Study.

Proponents of computer-assisted TKA suggest that better alignment of the TKAs will lead to improved long-term patient functional outcome and survivorship of the implants. However, there is little evidence about whether the improved position and alignment of the knee components obtained using computer navigation improve patient function and the longevity of the TKA. The purpose of this study was to determine whether (1) clinical results; (2) radiographic and CT scan results; and (3) the survival rate of TKA components would be better in patients having computer-assisted TKA than results of patients having TKA without computer-assisted TKA. In addition, we determined whether (4) complication rates would be less in the patients with computer-assisted TKA than those in patients with conventional TKA. We performed a randomized trial between October 2000 and October 2002 in patients undergoing same-day bilateral TKA; in this trial, one knee was operated on using navigation, and the other knee was operated on without navigation. All 296 patients who underwent same-day bilateral TKA during that period were enrolled. Of those, 282 patients (95%) were accounted for at a mean of 15 years (range, 14-16 years). A total of 79% (223 of 282) were women and the mean age of the patients at the time of index arthroplasty was 59 ± 7 years (range, 48-64 years). Knee Society knee score, WOMAC score, and UCLA activity score were obtained preoperatively and at latest followup. Radiographic measurements were performed including femorotibial angle, position of femoral and tibial components, level of joint line, and posterior condylar offset. Aseptic loosening was defined as a complete radiolucent line > 1 mm in width around any component or migration of any component. Assessors and patients were blind to treatment assignment. The Knee Society knee (92 ± 8 versus 93 ± 7 points; 95% confidence interval [CI], 92-98; p = 0.461) and function scores (80 ± 11 versus 80 ± 11 points; 95% CI, 73-87; p = 1.000), WOMAC score (14 ± 7 versus 15 ± 8 points; 95% CI, 14-18; p = 0.991), range of knee motion (128° ± 9° versus 127° ± 10°; 95% CI, 100-140; p = 0.780), and UCLA patient activity score (6 versus 6 points; 95% CI, 4-8; p = 1.000) were not different between the two groups at 15 years followup. There were no differences in any radiographic parameters of alignment (on radiography or CT scan) between the two groups. The frequency of aseptic loosening was not different between the two groups (p = 0.918). Kaplan-Meier survivorship of the TKA components was 99% in both groups (95% CI, 93-100) at 15 years as the endpoint of revision or aseptic loosening (p = 0.982). Anterior femoral notching was observed in 11 knees (4%) in the computer-assisted TKA group and none in the conventional TKA group (p = 0.046). In this randomized trial, with data presented at a minimum of 14 years of followup, we found no benefit to computer navigation in TKA in terms of pain, function, or survivorship. Unless another study at long-term followup identifies an advantage to survivorship, pain, and function, we do not recommend the widespread use of computer navigation in TKA because of its risks (in this series, we observed femoral notching; others have observed pin site fractures) and attendant costs. Level I, therapeutic study.

Hip resurfacing before 50years of age: A prospective study of 979 hips with a mean follow-up of 5.1years.

Hip resurfacing arthroplasty (HRA) is an alternative to total hip arthroplasty (THA) for the treatment of hip osteoarthritis in patients younger than 50 years. Data on revision rates after HRA are conflicting. The National Institute for Health and Care Excellence (NICE) recommends performing only those hip arthroplasty procedures associated with 10-year revision rates no greater than 5% (0.5% per year). Follow-up studies can rapidly determine whether this criterion is met. The uncertainties surrounding revision rates after HRA prompted us to design a study of prospectively enrolled patients aiming (1) to determine the revision rate after HRA performed before 50years of age and (2) to assess the functional, radiological, and biological outcomes of HRA. The revision rate after HRA performed before 50years of age meets the NICE criterion. Consecutive patients undergoing HRA before 50years of age were enrolled prospectively. The same implant was used in all patients. Functional outcomes were assessed based on the Harris Hip Score (HHS), Postel-Merle d'Aubigné (PMA) score, 12-item Oxford Hip Score (OHS), and UCLA activity score. Radiographic outcomes were assessed, and blood levels of chromium and cobalt were assayed. The study included 936 patients (979 HRAs) with a mean age of 42.7years (16.4-50.0years) at surgery and a mean follow-up of 5.1years (range: 3.1-9.0 years). All four mean functional scores were significantly improved at last follow-up vs. baseline: HHS, 95.9 (39.0-100) vs. 44.3 (18.0-83.0); PMA score, 17.6 (6.0-18.0) vs. 11.7 (3.0-16.0); OHS, 14.3 (12.0-37.0) vs. 40.6 (25.0-60.0); and UCLA activity score, 7.8 (2.0-10.0) vs. 5.6 (1.0-10.0) (p<0.0001). Mean cup inclination in the coronal plane was 42.1° (25.0°-68.0°). Mean blood cobalt level was significantly higher at last follow-up than at baseline (1.36μg/L [0.05-8.2μg/L] vs. 0.61μg/L [0.01-3.6]) (p<0.001). No patient experienced dislocation. Revision was required for 17 hips and involved changing the implant in 12 (1.2%). The 10-year survival rate with implant change, as the endpoint was 98.7% (95%CI, 97.6%-99.3%), indicating that the NICE criterion was easily met. The NICE criterion allows the rapid identification of prostheses with insufficient survival. HRA is theoretically associated with a high risk of aseptic mechanical loosening, as it is performed in young patients who have a high level of physical activity. Nevertheless, our study showed that implant survival after HRA was better than required by the NICE criterion. Thus, HRA is a valid alterative to THA in patients younger than 50years. IV, prospective study with no control group.

Predictive factors for metal ion levels in metal-on-metal total hip arthroplasty.

Although metal-on-metal (MoM) total hip arthroplasty (THA) and hip resurfacings (HR) have similar bearing surfaces and comparable wear rates, metal ion levels and risk of failure are higher for MoM-THA. The mechanism behind the increased metal ion levels in large head MoM-THA is not completely understood. The current study aims to identify predictive factors for increased metal ion levels in unilateral and bilateral large head MoM-THA. 99 Birmingham modular MoM-THA in 87 patients with metal ion levels at least 36months after index procedure were analyzed. Mean follow-up time was 61.3months (range 37-108) and the relationship of the following variables (gender, age, BMI, follow-up time, UCLA Activity Score, cup inclination, femoral head size, bilateral surgery) on metal ion levels were analyzed with multivariate regression models. Multivariate regression analysis revealed that bilateral MoM-THA surgery (p < 0.001) had a positive predictive effect on cobalt serum levels, while BMI had a negative (p = 0.018). Female gender (p = 0.012), activity (p = 0.001) and bilateral MoM-THA (p = 0.004) were positively correlated with chromium levels. Positive independent predictors for the cobalt-chromium ratio in the multivariate analysis were overall follow-up time (p = 0.004), bilateral MoM-THA (p < 0.001) and femoral head size (p = 0.007). The data of the current study suggest that bilateral MoM-THA, increased patient activity levels and female gender are associated with increased chromium levels. Patients with larger component size, longer follow-up time and bilateral MoM-THAs have an increased cobalt-chromium ratio. These patients might be at increased risk for adverse local soft tissue reactions secondary to corrosion. Continuous close monitoring is recommended and bearing-surface change should be discussed if local tissue reactions occur.

Hip abductor strength and fatigue are associated with activity levels more than 1 year after total hip replacement.

Despite improvements in pain and function, people who undergo total hip arthroplasty (THR) may not always return to desired levels of physical activity (PA). The factors associated with low activity levels are not fully understood. Abductor weakness and fatigue have both been proposed as factors that limit activity in older adults or people with hip osteoarthritis, but have not been investigated after THR. We hypothesized that abductor weakness and fatigue are associated with lower activity levels in people who have undergone a THR and that fatigue mediates the association between abductor strength and activity. We evaluated 16 subjects (24 ± 10 months post-THR; age 56.8 ± 8.4 yrs; BMI 31 ± 7 kg/m2 ). Fatigue was assessed using the PROMIS fatigue short-form 7a. Peak isometric hip abductor torque was assessed using a dynamometer with subjects in a sidelying position. We assessed activity level using the UCLA activity score. We used Pearson correlations to explore the associations among the variables. Next we used a three-step linear regression procedure to test whether or not fatigue acted as a mediator between abductor torque and UCLA activity scores. Higher abductor torque was associated with less fatigue (R2 = 0.275; p = 0.037) and with higher UCLA scores (R2 = 0.488, p = 0.003). Higher fatigue was associated with lower UCLA scores (R2 = 0. 307, p = 0.017), however there was no evidence of mediation. This suggests that addressing both abductor strength and fatigue may increase physical activity. Statement of Clinical Significance: Fatigue and abductor weakness should be evaluated in sedentary THR patients presenting for long-term follow-up. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1519-1525, 2018.

Comparison of High-Flexion Fixed-Bearing and High-Flexion Mobile-Bearing Total Knee Arthroplasties—A Prospective Randomized Study

BackgroundThere is none, to our knowledge, about comparison of high-flexion fixed-bearing and high-flexion mobile-bearing total knee arthroplasties (TKAs) in the same patients. The purpose of this study was to determine whether clinical results; radiographic and computed tomographic scan results; and the survival rate of a high-flexion mobile-bearing TKA is better than that of a high-flexion fixed-bearing TKA. MethodsThe present study consisted of 92 patients (184 knees) who underwent same-day bilateral TKA. Of those, 17 were men and 75 were women. The mean age at the time of index arthroplasty was 61.5 ± 8.3 years (range 52-65 years). The mean body mass index was 26.2 ± 3.3 kg/m2 (range 23-34 kg/m2). The mean follow-up was 11.2 years (range 10-12 years). ResultsThe Knee Society knee scores (93 vs 92 points; P = .531) and function scores (80 vs 80 points; P = 1.000), WOMAC scores (14 vs 15 points; P = .972), and UCLA activity scores (6 vs 6 points; P = 1.000) were not different between the 2 groups at 12 years follow-up. There were no differences in any radiographic and CT scan parameters between the 2 groups. Kaplan-Meier survivorship of the TKA component was 98% (95% confidence interval, 93-100) in the high-flexion fixed-bearing TKA group and 99% (95% confidence interval, 94-100) in the high-flexion mobile-bearing TKA group 12 years after the operation. ConclusionWe found no benefit to mobile-bearing TKA in terms of pain, function, radiographic and CT scan results, and survivorship. Longer-term follow-up is necessary to prove the benefit of the high-flexion mobile-bearing TKA over the high-flexion fixed-bearing TKA.

Short stem total hip arthroplasty for osteonecrosis of the femoral head in patients 60\xa0years or younger: a 3- to 10-year follow-up study

BackgroundIn young patients with osteonecrosis of the femoral head (ONFH), short-stem total hip arthroplasty (THA) could allow a potential advantage in preserving metaphyseal bone-stock, when revision surgery might become necessary. However, only a few studies have evaluated the outcome of short-stem THAs in ONFH. We reviewed the prospectively collected data of a cementless partial neck-retaining short-stem with ceramic-on-ceramic bearings in ONFH patients.MethodsThirty patients (37 hips) younger than 60 years (mean age at surgery, 51.5 years) underwent THA with the NANOS® stem (Smith and Nephew, Marl, Germany) from January 2006 to December 2012. All patients received a 32-mm or 36 mm ceramic femoral head. Harris hip score, WOMAC and UCLA activity score were recorded. Postoperative radiographs were evaluated for bone-implant fixation and osteolysis. Further analysis correlated clinical findings with implants characteristics and patient demographics at mean 5.6 years’ follow-up (range, 3–10 years).ResultsThe clinical and functional results improved significantly (p < 0.001). At latest follow-up, mean HHS, WOMAC, and UCLA activity scores were 90 (range, 71–100), 94 (range, 76–100), and 6.3 (range, 4–10) points, respectively. The diameter of the femoral head did not influence the clinical outcome (p = 0.661). All hips showed bone ingrowth fixation of the acetabular and femoral components. No patients showed osteolysis. No revision for any reason was performed during the study period.ConclusionsThe excellent clinical results and fixation pattern at mean 5.6 years’ follow-up reveal this implant as a reliable option in advanced stage of ONFH either. Further investigations are crucial to determine the long-term durability and to assess whether the association of ceramic-on-ceramic bearings, can be useful to achieve longer survivorship and lower complications rates.Trial registrationRegistry number: ISRCTN 91336248; date of registration: 04/07/2017.

Predictors of Hip Pain and Function in Femoroacetabular Impingement: A Prospective Cohort Analysis

Objectives:Joint pain and function at the time of surgery may influence postoperative rehabilitation, recovery and the final outcome of the patient. Little is known about how patient factors or pathologic findings predict hip pain or function in those presenting with femoroacetabular impingement (FAI). We hypothesized that patient factors including mental health would more strongly correlate with subjective assessments of hip pain and function compared to the extent of the intra- or extra-articular pathology (chondral damage, labral tear, cam or pincer deformities) in patients undergoing surgery for FAI.Methods:A prospective cohort of patients undergoing hip arthroscopy for FAI were enrolled between 2/2015 and 9/2016. Patients d HOOS-Pain, HOOS-Physical Function, VR12-MCS, VR12-PCS and UCLA activity questionnaires at the time of surgery. Surgeons documented intra-articular operative findings for each case by a standardized data collection method utilizing a mobile iPhone application. Multivariable linear regression models were created for continuous scores of HOOS-pain, HOOS-Physical Function and VR12-PCS as dependent variables. Independent variables studied included both patient factors and intra-operative anatomic and pathologic findings [Table 1].Results:During the study period, 396 patients undergoing arthroscopic surgery for FAI were enrolled. The mean patient age was 34±14 years, mean BMI 26.36±5.01 and 71% were female. The mean baseline scores were 45.94±17.07 for HOOS-Pain, 31.68±10.06 for VR-12 PCS and 40.99±17.75 for HOOS-Physical Function. The mean UCLA activity score was 5.04±2.57. Factors associated with worse HOOS-Pain scores include older age (p=0.01), female sex (p<0.001), smoking (p<0.001), years of education (p<0.001), lower VR-12 Mental Component Scores (p<0.001), lower UCLA activity scores (p<0.001) and presence of a labral tear diagnosed on hip arthroscopy (p=0.046) [Table 1]. Factors associated with worse HOOS-Physical function include female sex (p=0.004), smoking (p=0.01), fewer years of education (p=0.02), lower VR-12 MCS (p=0.002), and lower activity level (p<0.001). Factors associated with worse VR-12 PCS include increased age (p<0.001), female sex (p=0.02), smoking (p<0.001), and lower activity level (p<0.001).Conclusion:Patients with lower mental health scores, lower activity levels and those who smoke have predictably worse subjective hip pain and function when controlling for operative variables. While the presence of a labral tear does predict worse pain, the impact on subjective pain is weaker compared to patient factors such as mental health, smoking or female sex. Future studies evaluating patient outcomes after surgery for FAI should consider correcting for these identified patient factors in order to accurately interpret differences in patient reported outcomes. In order to determine the influence of these factors on the final outcome of the patient, further studies and follow-up are warranted.

How Comprehensive and Efficient are Patient Reported Outcomes for Femoroacetabular Impingement?

Objectives:Increasing emphasis is placed on patient reported outcomes following common orthopedic procedures as a measure of quality and patient satisfaction. When considering patient reported outcome (PRO) utilization in patients with hip pain secondary to femoroacetabular impingement, several different PRO exist with varying levels of utilization and accuracy. Understanding which disease-specific PRO may be most efficiently administered in patients with femoroacetabular impingement, particularly those undergoing arthroscopic hip procedures, may assist in promoting increased patient and physician adoption of these useful scores. Using a novel assessment criterion, this study assessed all commonly used PRO in hip arthroscopy literature. We hypothesize that surveys with fewer numbers of questions may remain comparable (with regards to comprehensiveness) to longer surveys.Methods:Commonly utilized PRO in hip arthroscopy literature were analyzed with regards to number of survey components, comprehensiveness, and efficiency. Comprehensiveness (maximum score 13) was scored as the total number of pain (at rest/baseline, at night, during activities of daily living, during sport, during work, and mechanical symptoms) and functional (range of motion, ability to perform ADL, sport, work, ability to sit, and pre-injury level of function) metrics included, along with inclusion of quality of life/satisfaction metrics. Efficiency was calculated as comprehensiveness divided by number of survey components.Results:Thirteen different PRO were studied. Number of components ranged from 1 (UCLA Activity Score) - 40 (HOOS). Only the iHOT-33 included all six pain components, while only the iHOT-33 and HOS PRO contained all six functional components. Seven PRO included a quality of life/satisfaction component. The most comprehensive scores were the iHOT-33 (score = 13) and HAGOS (score = 10), and the least comprehensive score was the UCLA (score = 2). The most efficient PROs were the UCLA, MHHS, and EQ-5D scores. The least efficient scores were the HOS and SF-36 scores.Conclusion:Many commonly utilized PRO for FAI are lacking in comprehensiveness and efficiency. Continued critical assessment of PRO quality may help practitioners identify the most comprehensive and efficient PRO to incorporate into daily clinical practice.Figure 1:Bar Graph of Comprehensiveness Scores with Overlying Line Graph of Efficiency Scores on Secondary Axis