Is There a Scientific Rationale for the Refixation of Delaminated Chondral Flaps in Femoroacetabular Impingement? A Laboratory Study.

BACKGROUND: Debonding of the acetabular cartilage is a characteristic type of hip damage found in cam-type femoroacetabular impingement (FAI), which remains a treatment challenge. In addition to resection, refixation of these flaps using fibrin sealants has been recently suggested. However, there is only limited evidence available that the proposed refixation method results in sufficient viable cartilage formation to ensure long-term flap grafting and restored tissue function. QUESTIONS/PURPOSES: To determine the flap tissue characteristics that would justify refixation of delaminated chondral flaps with a fibrin sealant, we characterized (1) the extracellular matrix (ECM) of chondral flaps in terms of chondrocyte viability and distribution of ECM components and (2) the chondrogenic potential of resident cells to migrate into fibrin and produce a cartilaginous matrix. METHODS: Ten acetabular chondral flaps and three non-delaminated control cartilage samples were resected during surgery. Chondrocyte viability was quantified using a live-dead assay. To assess the ECM, histological staining of glycosaminoglycans, collagen II, and collagen I allowed the qualitative study of their distribution. The ability of chondrocytes to migrate out of the ECM was tested by encapsulating minced flap cartilage in fibrin gels and semi-quantitatively assessing the projected area of the gel covered with migrating cells. The potential of chondrocytes to produce a cartilaginous matrix was studied with a pellet assay, a standard three-dimensional culture system to test chondrogenesis. Positive controls were pellets of knee chondrocytes of age-matched donors, which we found in a previous study to have a good capacity to produce cartilage matrix. Statistical significance of controlled quantitative assays was determined by the Student's t-test with Welch's correction. RESULTS: The proportion of viable chondrocytes in flaps was lower than in nondelaminated cartilage (50% ± 19% versus 76 ± 6%; p = 0.02). Histology showed a disrupted ECM in flaps compared with nondelaminated controls, with the presence of fibrillation, a loss of glycosaminoglycan at the delaminated edge, collagen II throughout the whole thickness of the flap, and some collagen I-positive area in two samples. The resident chondrocytes migrated out of this disrupted ECM in all tested samples. However in pellet culture, cells isolated from the flaps showed a qualitatively lower chondrogenic potential compared with positive controls, with a clearly inhomogeneous cell and matrix distribution and an overall smaller projected area (0.4 versus 0.7 mm; p = 0.038). CONCLUSION: Despite the presence of viable chondrocytes with migration potential, the cells resided in a structurally altered ECM and had limited capacity to deposit ECM, leading us to question their capacity to produce sufficient ECM within the fibrin sealant for stable long-term attachment of such flaps. CLINICAL RELEVANCE: The characterization of delaminated cartilage in cam FAI patients suggests that the refixation strategy might be adversely influenced by the low level of ECM produced by the residing cells.

Pain, activities of daily living and sport function at different time points after hip arthroscopy in patients with femoroacetabular impingement: a systematic review with meta-analysis.

AIM: To investigate pain, activities of daily living (ADL) function, sport function, quality of life and satisfaction at different time points after hip arthroscopy in patients with femoroacetabular impingement (FAI). DESIGN: Systematic review with meta-analysis. Weighted mean differences between preoperative and postoperative outcomes were calculated and used for meta-analysis. DATA SOURCES: EMBASE, MEDLINE, SportsDiscus, CINAHL, Cochrane Library, and PEDro. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies that evaluated hip pain, ADL function, sport function and quality of life before and after hip arthroscopy and postoperative satisfaction in patients with symptomatic FAI. RESULTS: Twenty-six studies (22 case series, 3 cohort studies, 1 randomised controlled trial (RCT)) were included in the systematic review and 19 in the meta-analysis. Clinically relevant pain and ADL function improvements were first reported between 3 and 6 months, and sport function improvements between 6 months and 1 year after surgery. It is not clear when quality of life improvements were first achieved. On average, residual mild pain and ADL and sport function scores lower than their healthy counterparts were reported by patients following surgery. Postoperative patient satisfaction ranged from 68% to 100%. CONCLUSIONS: On average, patients reported earlier pain and ADL function improvements, and slower sport function improvements after hip arthroscopy for FAI. However, average scores from patients indicate residual mild hip pain and/or hip function lower than their healthy counterparts after surgery. Owing to the current low level of evidence, future RCTs and cohort studies should investigate the effectiveness of hip arthroscopy in patients with FAI. TRIAL REGISTRATION NUMBER: CRD42015019649.

Clinical improvement and satisfaction after total joint replacement: a prospective 12-month evaluation on the patients' perspective.

PURPOSE: To determine short-term improvements, satisfaction rates and the patient acceptable symptom state (PASS) after total joint replacement (TJR) for different patient-reported outcome measures (PROMs). METHODS: This prospective cohort study included 426 consecutive patients undergoing total hip (n = 193) or knee arthroplasty (n = 233). The following PROMs were completed before TJR, and at 3, 6 and 12 months after surgery, respectively: WOMAC, Oxford Hip or Knee Score, Lower Extremity Functional Scale, University of California at Los Angeles (UCLA) activity scale and EuroQol-5 dimension (EQ-5D). Satisfaction rates and the PASS thresholds were also assessed. RESULTS: THA patients improved quicker and achieved higher outcome scores than TKA patients. Comorbidities according to the Sangha score were moderately correlated with all PROM values in an inverse direction at all time points (r = -0.27 to -0.47, p < 0.01) in both groups. Satisfaction with the result of surgery improved over time. At 12 months, more than 90 % of the patients were satisfied or very satisfied with the achieved result. The THA group showed a higher proportion of very satisfied patients than the TKA group at all time points. PASS thresholds increased over time for all PROMs except for the UCLA and the EQ-5D in TKA patients. CONCLUSIONS: More than 90 % of the patients will be satisfied 1 year after TJR. THA patients recover faster than TKA patients, i.e., they achieve higher PROM values at earlier follow-up time points. Cutoff values defining a successful result in terms of the PASS could be defined for all PROMs at different time points and can serve as reference for future studies and patient-oriented follow-ups.

The German Lower Extremity Functional Scale (LEFS) is reliable, valid and responsive in patients undergoing hip or knee replacement.

PURPOSE: To determine the measurement properties of a German version of the Lower Extremity Functional Scale (LEFS) in patients with hip or knee osteoarthritis undergoing total joint replacement (TJR). METHODS: This prospective cohort study included 486 consecutive patients. The LEFS and other self-reported outcome measures were administered at different time points and several classical measurement properties were determined. RESULTS: The German LEFS was highly reliable (ICC 0.98) and internally consistent (CA 0.95). Construct validity was proven by large to very large correlations (r = 0.52-0.91) with all other instruments in the expected directions. Factor analysis using a polychoric correlation matrix revealed two factors at baseline and 6 months explaining about 70% of the total variance. There were no floor or ceiling effects for the total score, but significant floor effects for the single items 16-19 at baseline. The LEFS was highly responsive at 6 months. CONCLUSIONS: The German LEFS proved to be a reliable, valid and responsive tool for the self-assessment of patients undergoing total hip or knee replacement. Nevertheless, the questionnaire seems to summarize more than one construct as highlighted by the factor analysis. Further research seems therefore warranted.

Women demonstrate more pain and worse function before THA but comparable results 12 months after surgery.

BACKGROUND: Many studies report differences in patient-reported outcome measures (PROMs) for men and women undergoing total hip arthroplasty (THA). Few studies have evaluated whether these are explained by corresponding differences in important preoperative factors. QUESTIONS/PURPOSES: (1) Are there differences between men and women in PROM scores preoperatively and 12 months after THA? (2) Do baseline differences in comorbidity, age, body mass index (BMI), and mental health status explain these differences in PROM scores? METHODS: Preoperatively, 300 patients completed the Oxford Hip Score (OHS), WOMAC, and SF-12; 261 (86%) of them (129 women, 64 ± 11 years; 132 men, 66 ± 10 years) completed the same questionnaires 12 months postoperatively and also rated the acceptability of their current symptoms and change in general health. RESULTS: Preoperatively, women showed worse scores than men in the OHS (-1.9; 95% confidence interval, -3.6 to -0.3) and WOMAC (-6.3; -10.9 to -1.7). At 12 months postoperatively, the absolute scores for all PROMs were not significantly different. After controlling for BMI, age, comorbidity, SF-12 mental health scores, and sociodemographic characteristics, the baseline differences remained. CONCLUSIONS: Surgeons may be more reluctant to operate on women than men because they perceive that, because of their worse baseline status, women are likely to have worse outcomes; however, given that we found no evidence for differences in patient-reported outcomes at 12 months, these suspicions would appear to be unfounded. Women and men can be expected to benefit to a similar extent from THA. LEVEL OF EVIDENCE: Level III, therapeutic study.

No regeneration of the human acetabular labrum after excision to bone.

BACKGROUND: Treatment options for a symptomatic, torn, irreparable, or completely ossified acetabular labrum are limited to either excision and/or reconstruction with grafts. In a previous animal model, regeneration of the acetabular labrum after excision to the bony rim has been shown. In humans, less is known about the potential of regeneration of the labrum. Recent studies seem to confirm labral regrowth, but it is still unclear if wide excision might be a surgical option in cases where repair is not possible. QUESTIONS/PURPOSES: The purposes of this study were (1) to determine the extent of acetabular labrum regeneration after excision to the bony rim; and (2) to determine whether this procedure results in higher hip scores. METHODS: We reviewed all patients treated with surgical dislocation for symptomatic femoroacetabular impingement by a single surgeon at one institution between 2003 and 2008, of whom 14 underwent wide labral excision (of at least 60°) down to bone; we used this approach when there was an absence of reparable tissue. Of these 14, nine were available for voluntary reexamination. The mean age at surgery was 38 ± 9 SD years and the mean followup was 4 ± 1 SD years. All patients consented to a physical examination and an MRI arthrogram, which was evaluated for evidence of new tissue formation by four observers. A modified Harris hip score and the UCLA were recorded. RESULTS: Regrowth of a structure equivalent to normal labrum was not observed on the MRI arthrograms. Six of nine hips had segmental defects, bone formation was found in five, and the capsule was confluent with the new tissue in six. The mean Harris hip score at latest followup was 83 ± 14, and the mean UCLA score was 6 ± 2. CONCLUSIONS: Resection of a nonreparable acetabular labrum down to a bleeding bony surface does not stimulate regrowth of tissue that appears to be capable of normal function by MR arthrography, and patients who underwent this procedure had lower hip scores at midterm than previously reported from the same institution for patients undergoing labral repair or sparse débridement. Based on these results, we believe that future studies should evaluate alternatives to reconstructing the labrum, perhaps using ligamentum teres, because resection seems neither to result in regrowth nor the restoration of consistently high hip scores.

Validation of the Core Outcome Measures Index in Patients With Femoroacetabular Impingement.

PURPOSE: To evaluate a short, hip-oriented outcome instrument, based on the Core Outcome Measures Index (COMI), in patients undergoing surgery for femoroacetabular impingement (FAI). METHODS: The following full-length questionnaires were completed preoperatively and at 6 and 12 months postoperatively by 159 consecutive FAI patients: Hip Outcome Score (HOS); Oxford Hip Score; Western Ontario and McMaster Universities Arthritis Index; Short Form 12 Health Survey; World Health Organization Quality of Life questionnaire, short version; and EuroQol-Five Dimensional index. The scores for the 6 hip-oriented Core Outcome Measures Index (COMI-Hip) items-addressing pain, function, symptom-specific well-being, quality of life, and disability-were extracted from established full-length questionnaires, and their performance as an index was compared with that of the full-length instruments. RESULTS: Scores for the single items of the COMI-Hip questionnaire correlated well with the scores for the corresponding full-length instruments from which they were extracted (r = -0.89 to -0.62, P < .001). The COMI-Hip sum score also correlated well with the Oxford Hip Score and the Western Ontario and McMaster Universities Arthritis Index pain and function scores (r = -0.85 to -0.70, P < .001), as well as with the HOS (r = -0.72 to -0.60, P < .001), an instrument specifically developed for assessing FAI patients. Internal responsiveness (Cohen d for effect size) of the COMI-Hip sum score from preoperatively to 12 months postoperatively was similar to that of the HOS activities-of-daily living subscale (d = -0.76 and d = -0.68, respectively; P < .001). Significant correlations were found between the change scores of the COMI-Hip sum score and those of the HOS activities-of-daily living and sport subscales at 6 months (r = -0.62 and r = -0.60, respectively; P < .001) and 12 months (r = -0.69 and r = -0.61, respectively; P < .001), showing the external responsiveness of the COMI-Hip. CONCLUSIONS: The COMI-Hip is a simple yet valid and responsive outcome instrument for the efficient assessment of patients undergoing surgery for FAI. It performs at least as well as the current reference instrument for FAI, the HOS, and can therefore be considered a potentially valuable instrument for routine use in both research and clinical practice. LEVEL OF EVIDENCE: Level II, development of diagnostic criteria based on consecutive patients (with universally applied reference gold standard).

Validity, reproducibility, and responsiveness of the oxford hip score in patients undergoing surgery for femoroacetabular impingement.

PURPOSE: To examine the validity, reproducibility, and responsiveness of the Oxford Hip Score (OHS) in patients with femoroacetabular impingement (FAI). METHODS: One hundred twenty-six consecutive patients with FAI and 550 patients undergoing total hip arthroplasty (THA) completed the OHS and the Hip Outcome Score (HOS) at baseline and at 6 and 12 months postoperatively. The patients also rated the global treatment outcome ("How much did the operation help your hip problem?") on a 5-point Likert scale. Sixty-eight FAI and 96 THA patients completed the OHS twice within 2 weeks so that we could assess its reproducibility. RESULTS: The reproducibility of the OHS was good and was similar for THA and FAI patients (standard error of measurement of 5.6% for THA and 6.2% for FAI and intraclass correlation coefficient of 0.97 for both FAI and THA). In the FAI group, the correlations between the OHS and HOS subscale scores were strong (r = 0.67 to 0.85). The internal responsiveness (standardized response mean) of the OHS in FAI patients was high and similar to that of the HOS (from 0.84 to 1.48 for the OHS and from 0.75 to 1.53 for the HOS). External responsiveness was confirmed by the strong correlations between the change scores for the 2 instruments (r = 0.60 to 0.76) and between the change scores of the OHS and the global treatment outcome score (r = 0.52 to 0.60). No floor or ceiling effects were found, and internal consistency was high (Cronbach α = 0.94). Exploratory factor analysis showed a 2-factor structure for the OHS in both the THA and FAI groups. CONCLUSIONS: We conclude that the OHS, though originally developed for patients undergoing THA, represents an appropriate outcome instrument for assessing pain and function in FAI patients treated with arthroscopy or mini-open surgery. LEVEL OF EVIDENCE: Level III, diagnostic study of consecutive patients (without consistently applied reference gold standard).

Validation of a self-reported Beighton score to assess hypermobility in patients with femoroacetabular impingement.

PURPOSE: The prevalence of joint hypermobility (JH) in patients with femoroacetabular impingement (FAI) and its association with outcomes is yet widely unknown. This study aimed to validate a self-reported version of the Beighton score for FAI patients, and to determine possible associations between JH and clinical and radiographic parameters. METHODS: The study included 55 consecutive patients (18 females, mean age 29 years) with a diagnosis of FAI. Patients completed a self-reported Beighton score before clinical assessment, and a clinician blinded to the self-reported form filled the examiner-based version. Reliability of the self-reported version was assessed using kappa statistics. The prevalence of JH and associations with clinical and radiographic parameters were determined. RESULTS: The patients scored a mean of 2.6 points on the self-reported Beighton score. Agreement between self-assessment and examination was good to excellent for all single items and for the total score. Considering a Beighton score of ≥4 as cutoff for JH, the prevalence in the present cohort was 32.7% (50% of females and 24.3% of males). Significant associations were found between Beighton scores and hip joint motion. While no direct correlations were found between Beighton scores and the radiographic parameters; the group of patients with JH differed considerably from that without JH regarding gender distribution and FAI type. CONCLUSIONS: The patient-oriented Beighton score proved to be feasible and reliable in FAI patients. The prevalence of JH in these patients seems to be high and future investigations about the association of JH with FAI and treatment outcomes are therefore warranted.

Skin crease 'bikini' incision for anterior approach total hip arthroplasty: surgical technique and preliminary results.

BACKGROUND: The direct anterior approach for THA allows implantation through an internervous plane without muscle detachment from bone. However, the classic longitudinal skin incision does not follow the anatomic skin creases and can result in scar widening. We therefore modified our incision technique to a short oblique skin incision following the anatomic skin crease of the groin. QUESTIONS/PURPOSES: We sought to determine whether (1) the oblique incision leads to improved scar results compared with the longitudinal incision, (2) functional and pain scores are similar between the two approaches, and (3) the new incision is safe with respect to complications, blood loss, implant position, and lateral femoral cutaneous nerve (LFCN) symptoms. METHODS: Fifty-nine patients underwent THAs using either the classic (n = 33) or the new oblique incision (n = 26). At 6 months after surgery, we compared objective and subjective scar results, WOMAC, Oxford Hip and UCLA scores, blood loss, cup inclination, and the presence of LFCN symptoms between both groups. RESULTS: Objectively, the modified incision resulted in significantly shorter and narrower scars. Subjectively, patients in the modified incision group were substantially more satisfied with the aesthetic appearance. Functional and pain scores were similar. No complications occurred in either group. Blood loss and cup inclination did not differ between the two groups. There were no differences in LFCN symptoms. CONCLUSIONS: In this series, which selected for thinner patients in the study group, the 'bikini' incision for an anterior approach THA led to improved scar cosmesis and was found to be safe in terms of blood loss, appropriate component placement, and risk for LFCN injury. LEVEL OF EVIDENCE: Level III, retrospective comparative study. See the Guidelines for Authors for a complete description of levels of evidence.

A Core Outcome Measures Index (COMI) for patients undergoing hip arthroplasty.

Outcome is best assessed with both generic and disease-specific instruments, but using many, lengthy questionnaires increases the burden, quality, and cost of data collection.We evaluated a short, hip-oriented Core Outcome Measures Index (COMI-hip), comprising six items (pain, function, symptom-specific well-being, quality of life, and disability) extracted from established full-length questionnaires; 214 consecutive total hip arthroplasty (THA) patients participated. Scores for the single items and sum-score of COMI-hip correlated well with those of the full-length instruments (r= -0.56 to -0.88). At 6 and 12 months' follow-up, the COMI-hip showed similar responsiveness (Cohen's d for effect size, 1.36-3.08) to the full-length questionnaires (1.65-2.34). The COMI-hip proved a simple but valid outcome instrument in THA patients. Its brevity renders it a potentially valuable instrument for routine use.

Piriformis muscle rupture during total hip arthroplasty using a muscle-preserving posterior approach.

Total hip arthroplasty via muscle-sparing approaches is advocated and performed with increasing frequency. However, performing total hip arthroplasty through muscle-sparing approaches may require a more forceful retraction, which in turn may damage the muscles which the less invasive approach intended to preserve. We report on the rupture of the piriformis muscle during primary total hip replacement performed through a posterior approach intended to preserve this muscle. The prevalence and effects of such iatrogenic injuries are currently unknown, although unrecognised muscle damage may be a potential reason why early postoperative gait analyses could not demonstrate the expected benefits of less invasive surgery. Surgeons should be aware of this potential complication when performing total hip arthroplasty through a less invasive posterior approach.

Surgical technique: Second-generation bone marrow stimulation via surgical dislocation to treat hip cartilage lesions.

BACKGROUND: Compared to knees, hips have more bony constraint and soft tissue coverage. Thus, repair of focal cartilage defects in hips requires more invasive and technically complex surgeries than simple arthroscopy or arthrotomy. Autologous matrix-induced chondrogenesis (AMIC) is a second-generation bone marrow stimulation technique. Improvement in Tegner, Lysholm, International Cartilage Repair Society (ICRS), and Cincinnati scores has been reported at 1 and 2 years after AMIC in knees. AMIC is potentially useful to repair defects in hips, but it is unknown whether it relieves symptoms or results in a durable construct. DESCRIPTION OF TECHNIQUE: A surgical hip dislocation is used to access the defect. This is débrided to stable cartilage shoulders, necrotic bone is removed, and the lesion base is drilled. Autogenous bone graft is used for lesions with bony defects to create a level surface. Fibrin gel and a collagen membrane are placed to stabilize the superclot for fibrocartilage formation. METHODS: We treated six patients with AMIC in the hip between 2009 and 2010. We obtained Oxford Hip and UCLA Activity Scores. Repair quality was assessed on 6-month postoperative MRI using the modified magnetic resonance observation of cartilage repair tissue (MOCART) system. Minimum 1-year followup data were available for four patients (range, 1-2.5 years). RESULTS: Postoperative Oxford Hip Scores ranged from 13 to 17, UCLA Activity Scores ranged from 5 to 10, and MOCART scores ranged from 55 to 75. No complications occurred. CONCLUSIONS: We describe AMIC in the hip. Although these patients had pain relief and improved function, long-term followup is necessary to assess the duration of improvement, durability of repair, and potential for arthrosis. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Combination of first metatarsophalangeal joint arthrodesis and proximal correction for severe hallux valgus deformity.

BACKGROUND: Arthrodesis of the first metatarso-phalangeal (MTP-1) joint is a widely accepted procedure for the treatment of hallux valgus in patients with MTP-1 degeneration, severe or recurrent deformity, or inflammatory arthritis. This study aimed to evaluate if an additional more proximal correction was beneficial in cases with a severely increased intermetatarsal 1-2 angle (IMA 1-2). METHODS: A consecutive series of 18 feet (4 bilateral, all females; mean age, 61 years) with severe hallux valgus and an increased IMA 1-2 treated by MTP-1 fusion and an additional more proximal correction (Mau osteotomy or modified Lapidus procedure) was evaluated. Radiographs were analyzed for IMA 1-2 and hallux valgus angles (HVA), and for the position of the tibial sesamoid according to the AOFAS guidelines. RESULTS: At a mean followup of 14 months, all patients were satisfied or very satisfied with the results of surgery. There were no intraoperative complications. The IMA 1-2 significantly improved from a mean of 18.8 degrees before surgery to 4.6 degrees at followup (p < 0.001) and the HVA from a mean of 49.9 degrees to 9.7 degrees (p < 0.001), respectively. Sesamoid position improved two grades on average. We found no difference between the Mau osteotomy and the modified Lapidus procedure. CONCLUSION: The present results indicate that the combination of a more proximal procedure with a MTP-1 arthrodesis in cases of hallux valgus with severely increased IMA 1-2 has a high correction capability and achieved normal HVAs as well as normal IMAs 1-2. This technique appeared to be safe and clinically successful.

Mid-term outcomes of exercise therapy for the non-surgical management of femoroacetabular impingement syndrome: are short-term effects persisting?

OBJECTIVES: To investigate the mid-term outcomes of exercise therapy in patients with femoroacetabular impingement syndrome (FAIS). DESIGN: Follow-up study. SETTING: Clinical setting. PARTICIPANTS: Twenty-six patients with FAIS who completed a 12-week semi-standardized, progressive exercise therapy program. MAIN OUTCOME MEASURES: At a mid-term follow-up of 4.6 years, therapy outcome was assessed using (i) the Global Treatment Outcome questionnaire for hip pain, (ii) the Hip Outcome Score (HOS) for hip pain and function in activities of daily living (ADL) and Sport and (iii) the Hip Sports Activity Scale (HSAS) for sport activity level. Mid-term outcomes were compared to pre-symptomatic, pre-therapy, as well as to short-term follow ups (18 weeks). RESULTS: In patients who completed the exercise program and did not undergo hip surgery (N = 19), mid-term HOS ADL and HOS Sport (P = 0.002) were higher than pre-therapy, and comparable to the 18-week follow-up. Mid-term HSAS was lower than the pre-symptomatic status (P = 0.022), but comparable to the 18-week follow-up. CONCLUSION: At a mid-term follow-up of 4.6 years, FAIS patients with no subsequent hip surgery maintained the good exercise therapy outcomes and the level of sport activity achieved at short term.

High revision rate at 5 years after hip resurfacing with the Durom implant.

BACKGROUND/RATIONALE: There is growing evidence that different resurfacing implants are associated with variable survival and revision rates. A registry analysis indicated the Durom resurfacing implant had high revision rates at 5 years, whereas three original studies reported low revision rates at short-term followups. Thus, the revision rates appear controversial. QUESTIONS/PURPOSES: We therefore assessed (1) the survivorship including differences between women and men at a mean of 5 years after resurfacing with the Durom implant, and (2) clinical scores and radiographic parameters. PATIENTS AND METHODS: We prospectively followed all 100 Durom hip resurfacings implanted in 91 patients (25 women and 66 men; mean age, 52 years) between 2003 and 2004. Survivorship analysis was performed with pending revision or revision for any reason as the endpoint. The minimum followup was 47 months (mean, 60 months; range, 47-72 months). RESULTS: At a mean of 5 years, 11 hips were revised for various reasons. Cumulative survival was 88.2% for all patients and 81.5% for women. The mean Oxford (OHS) and Harris hip (HHS) scores were 14.6 and 94.7, respectively. The mean UCLA activity level was 7.9. Sclerotic changes around the short femoral stem (pedestal sign) were detected in 40% of the hips. We observed considerable femoral neck thinning with component-to-neck ratios of 0.85 preoperatively and 0.82 at 5 years. CONCLUSIONS: Our study highlights a high revision rate 5 years after hip resurfacing with the Durom implant. This observation underlines previous findings from registry data and suggests that revision rates increase with time. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

The German Hip Outcome Score: validation in patients undergoing surgical treatment for femoroacetabular impingement.

PURPOSE: To cross-culturally adapt and validate the Hip Outcome Score (HOS) for use in German-speaking patients undergoing surgical treatment for femoroacetabular impingement. METHODS: After cross-cultural adaptation (German-language version of the HOS [HOS-D]), the following metric properties of the questionnaire were assessed in 85 consecutive patients (mean age, 33.4 years; 36 women) undergoing hip arthroscopy or surgical hip dislocation: feasibility, reliability, internal consistency, and construct validity (correlation with Western Ontario and McMaster Universities Arthritis Index, Oxford Hip Score, Short Form 12, and University of California, Los Angeles activity scale). We calculated floor and ceiling effects taking the minimal detectable change into account. RESULTS: The activities of daily living subscale of the HOS-D could be scored in all cases and the sport subscale in all but one. The HOS-D scores were highly reproducible with intraclass correlation coefficients of 0.94 for the activities of daily living subscale and 0.89 for the sport subscale. Internal consistency was confirmed by Cronbach α values >0.90 for both subscales. Correlation coefficients with the other measures ranged from -0.08 (Mental Component Scale of Short Form 12) to -0.90 (Western Ontario and McMaster Universities Arthritis Index function subscale). CONCLUSIONS: The HOS-D is a reliable and valid self-assessment tool for patients undergoing surgical femoroacetabular impingement treatment. By use of the HOS, comparisons between studies and treatment regimens involving either German- or English-speaking patients are now possible. LEVEL OF EVIDENCE: Level I, testing of previously developed diagnostic criteria in a series of consecutive patients with universally applied gold standard.

Comparison of the reliability, responsiveness, and construct validity of 4 different questionnaires for evaluating outcomes after total knee arthroplasty.

The study aimed to compare the reliability, responsiveness and construct convergent validity of four questionnaires (Western Ontario and McMaster Universities Osteoarthritis Index, Activities of Daily Living of the Knee Outcome Survey, Oxford Knee Score, and the 12-item Short Form Health Survey) in total knee arthroplasty patients. Seventy-nine patients completed the questionnaires before surgery and 6 months later. The reliability was high for all instruments with intraclass correlation coefficients from 0.81 to 0.96 and SEMs from 6.6% to 28.3% of mean scores. The score changes after surgery were three- to five-fold the instruments' measurement error. The responsiveness was large for all instruments. In conclusion most of the selected instruments were reliable and responsive. It was not possible to clearly identify a "best" or "better" tool and hence all can be considered useful, with the reported psychometric properties serving to guide the choice of instrument for a given purpose.