Gluteus Maximus Transfer for Irreparable Hip Abductor Deficiency: A Systematic Review and Meta-Analysis.

BACKGROUND: Gluteus maximus tendon transfer has recently been described as a treatment option for irreparable abductor tendon tears. The purpose of this study was to systematically review outcomes following gluteus maximus tendon transfer for hip abductor deficiency. METHODS: The published literature was queried for outcomes following gluteus maximus transfer in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Outcomes of interest included preoperative and postoperative functional scores, resolution of pain and gait abnormalities, postoperative rehabilitation protocols, surgical complications, reoperation rates, and postoperative magnetic resonance imaging. In total, 10 studies with a total of 125 patients (76% women) with a mean age of 67 years (range, 30 to 87) were identified for inclusion. RESULTS: Modified Harris Hip Score (+30.1 ± 6.6 [95% confidence interval: +15.5 to +46.5]) and Visual Analog Scale for pain (-4.1 ± 1.1 [95% confidence interval: -7.1 to -1.0]) were improved following gluteus maximus transfer, compared to preoperative levels. No significant improvement was noted in abduction strength and 33% of patients demonstrated a residual Trendelenburg gait postoperatively. The overall complication rate was 5.6% (7 of 125), with a reoperation rate of 1.6% (2 of 125). CONCLUSIONS: Gluteus maximus tendon transfer for abductor insufficiency has demonstrated reliable outcomes at 3 years, with improvement in hip function and pain. However, patients demonstrate modest improvements in abduction strength, and a significant subset will continue to demonstrate a Trendelenburg gait postoperatively.

Otto Aufranc Award: Identification of Key Molecular Players in the Progression of Hip Osteoarthritis Through Transcriptomes and Epigenetics.

BACKGROUND: This study aimed: (1) to compare the transcriptome profile of articular cartilage in cam-FAI (early stage) to advanced OA secondary to cam-FAI (late stage) and (2) to investigate epigenetic changes through the expression of DNA methylation enzymes DNMT3B, DNMT1, and DNMT3A and peroxisome proliferator-activated receptor gamma (PPARγ) in human cartilage samples during the progression of hip OA. METHODS: Full-thickness cartilage samples were collected from the anterolateral head-neck junction (impingement zone) of 22 patients (9 early-FAI and 13 late-FAI). RNA sequencing and in vitro cartilage cultures with histological analysis and immunohistochemistry staining for PPARγ and DNMT3B were performed. Target gene validation was confirmed with RT-PCR. RESULTS: Fifty genes and 42 pathways were identified differentially between early and late-FAI (fold change <-1.5 or >1.5, P < .01). PPARγ and DNMT3B were gradually suppressed with disease progression. Contrarily, disease progression induced expression of DNMT1/3A. CONCLUSION: By comparing comprehensive gene expression in early and late stage hip degeneration at the whole-genome level, distinct transcriptome profiles for early and late stage disease were identified along with key molecular contributors to the progression of hip OA. Preservation of endogenous PPARγ may have therapeutic potential to delay or prevent hip OA.

What Mid-term Patient-reported Outcome Measure Scores, Reoperations, and Complications Are Associated with Concurrent Hip Arthroscopy and Periacetabular Osteotomy to Treat Dysplasia with Associated Intraarticular Abnormalities?

BACKGROUND: Periacetabular osteotomy (PAO) is a well-accepted treatment for acetabular dysplasia, but treatment success is not uniform. Concurrent hip arthroscopy has been proposed for select patients to address intraarticular abnormalities. The patient-reported outcomes, complications, and reoperations for concurrent arthroscopy and PAO to treat acetabular dysplasia remain unclear. QUESTIONS/PURPOSES: (1) What are the functional outcome scores among select patients treated with PAO plus concurrent hip arthroscopy at mid-term follow-up? (2) What factors are associated with conversion to THA or persistent symptoms (modified Harris hip score ≤ 70 or WOMAC pain subscore ≥ 10)? (3) What proportion of patients underwent further hip preservation surgery at mid-term follow-up? (4) What are the complications associated with the procedure? METHODS: Between November 2005 and December 2012, 78 patients (81 hips) who presented with symptomatic acetabular dysplasia-defined as a lateral center-edge angle less than 20° with hip pain for more than 3 months that interfered with daily function-had undergone unsuccessful nonsurgical treatment, had associated intraarticular abnormalities on MRI, and underwent combined hip arthroscopy and PAO. Eleven patients did not have minimum 4-year follow-up and were excluded, leaving 67 patients (70 hips) who met our inclusion criteria and had a mean follow-up duration of 6.5 ± 1.6 years. We retrospectively evaluated patient-reported outcomes at final follow-up using the University of California Los Angeles (UCLA) activity score, the modified Harris Hip Score (mHHS), and the WOMAC pain subscore. Conversion to THA or persistent symptoms were considered clinical endpoints. Repeat surgical procedures were drawn from a prospectively maintained database, and major complications were graded according to the validated Clavien-Dindo classification (Grade III or IV). Student t-tests, chi-square tests, and Fisher exact tests identified the association of patient factors, radiographic measures, and surgical details with clinical endpoints. For patients who underwent bilateral procedures, only the first hip was included in our analyses. RESULTS: At final follow-up, the mean mHHS for all patients improved from a mean ± SD of 55 ± 19 points to 85 ± 17 points (p < 0.001), the UCLA activity score improved from 6.5 ± 2.7 points to 7.5 ± 2.2 points (p = 0.01), and the WOMAC pain score improved from 9.1 ± 4.3 points to 3.2 ± 3.9 points (p < 0.001). Three percent (2 of 67) of patients underwent subsequent THA, while 21% (15 of 70) of hips were persistently symptomatic, defined as mHHS less than or equal to 70 or WOMAC pain subscore greater than or equal to 10. Univariate analyses indicated that no patient demographics, preoperative or postoperative radiographic metrics, or intraoperative findings or procedures were associated with subsequent THA or symptomatic hips. Worse baseline mHHS and WOMAC pain scores were associated with subsequent THA or symptomatic hips. Seven percent (5 of 67) of patients underwent repeat hip preservation surgery for recurrent symptoms, and 4% (3 of 67) of patients had major complications (Clavien-Dindo Grade III or IV). CONCLUSION: This study demonstrated that concurrent hip arthroscopy and PAO to treat symptomatic acetabular dysplasia (with intraarticular abnormalities) has good clinical outcomes at mid-term follow-up in many patients; however, persistent symptoms or conversion to THA affected almost a quarter of the sample. We noted an acceptable complication profile. Further study is needed to directly compare this approach to more traditional techniques that do not involve arthroscopy. We do not use isolated hip arthroscopy to treat symptomatic acetabular dysplasia. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Editorial Commentary: Reach Over the Top and Preserve the Hip Labrum.

There is increasing interest in fine tuning of hip arthroscopy to improve the long-term outcomes of femoroacetabular impingement (FAI) surgery. Recently, some advocated for rim trimming and labral refixation without taking down the labrum, using a so-called over-the-top technique. Although some studies have already reported on the outcomes of this procedure, very few have focused on how maintaining an unharmed chondrolabral junction may decrease cartilage wear over time. Preserving labral attachment should be the standard of care in the treatment of FAI, to keep the suction seal working normally.

Patients With Symptomatic Sequelae of Slipped Capital Femoral Epiphysis Have Advanced Cartilage Wear at the Time of Surgical Intervention.

BACKGROUND: Slipped capital femoral epiphysis (SCFE) is a common hip problem in children. The resulting deformity can cause impingement similar to cam-type idiopathic femoroacetabular impingement (FAI). Although there are similarities between FAI and SCFE, deformity patterns, severity, and time of onset of symptoms varies, which may impact management. The purpose of this study was to describe patterns of articular cartilage damage in patients undergoing surgical hip dislocation for sequelae of SCFE in comparison to patients undergoing arthroscopic surgery for primary FAI. METHODS: Patients were identified who underwent surgical treatment for hip pain due to primary FAI (cam type) or sequelae of SCFE. Clinical data and radiographic measurements were recorded. Cartilage was assessed intraoperatively. Severity was classified using the modified Beck classification, while location was classified into 6 sectors. Statistical analysis was performed to test for differences in demographic and radiographic characteristics between the SCFE and FAI patients. χ2 or Fisher exact tests were used to evaluate trends in patterns of acetabular and femoral cartilage wear between SCFE and FAI groups. RESULTS: The SCFE group had 28 hips compared with 304 in the FAI group. SCFE patients were younger (19 vs. 32, P<0.001), had higher body mass index (30±5.9 vs. 24±4.8, P<0.001), and were more often male (61% vs. 27%, P<0.001). Deformity severity based on α-angle was higher in the SCFE group [AP 74 vs. 55 (P=0.001) and Dunn 72 vs. 58 (P<0.001)]. There were no significant differences with regards to lateral center edge angle, anterior center edge angle, or Tonnis angle. In both groups the most common locations for cartilage lesions in both groups were the anterior peripheral and superolateral peripheral regions with fewer but more widely distributed femoral head lesions. The SCFE group had higher rates of femoral head and superolateral central cartilage lesions compared with the FAI group. There was no statistical difference between high-grade femoral or acetabular cartilage lesions between groups. CONCLUSIONS: Patients with SCFE were younger at the time of surgery and presented with more severe deformity based on radiographic α-angle compared to patients with FAI. Our results suggest higher prevalence of femoral head lesions and more diffuse cartilage injury in patients with SCFE. This study can be used to support early surgical intervention in patients with symptomatic sequelae of SCFE due to risk of premature joint damage. LEVEL OF EVIDENCE: Level III-prognostic study.

Editorial Commentary: The Competitive Dancer's Hip-An Acquired Flexible Attitude to a High-Performance Hip.

Competitive dancers have a high prevalence of hip injuries. The dancer's hip is a unique scenario in which hip impingement is associated with compensatory soft-tissue laxity. Particularly in these athletes, normal osseous hip morphology with symptomatic femoroacetabular impingement may be observed. The repetitive training, including extreme daily hip range of motion, results in compensatory soft-tissue laxity and secondary impingement-induced subluxation. Peculiarly, hip impingement in dancers occurs in the posterosuperior aspect of the hip and extra-articularly between the anterior inferior iliac spine and the distal femoral neck (subspinous impingement). Normal or even dysplastic hips might impinge during extreme range of motion. An atypical osteochondroplasty, including a subtle distal-based femoral resection, anterior inferior iliac spine decompression, and excellent management of the capsule, should be considered in this population for a successful outcome. Hip dysplasia should always be ruled out in these athletes, and if present, a periacetabular osteotomy should be indicated.

Open Reduction and Internal Fixation for the Treatment of Symptomatic Osteochondritis Dissecans of the Femoral Head in Patients With Sequelae of Legg-Calvé-Perthes Disease.

BACKGROUND: Osteochondritis dissecans (OCD) is estimated to occur in 2% to 7% of patients with Legg-Calvé-Perthes disease (LCPD). Unstable osteochondral fragments secondary to LCPD may produce mechanical symptoms requiring surgical intervention. Reattachment of the fragment with open reduction and internal fixation (ORIF) may provide good clinical outcomes. The purpose of this study is to report short-term clinical and radiographic results of ORIF for the treatment of symptomatic osteochondral lesions resulting from LCPD. METHODS: Clinical data including patient demographics and patient-reported outcome scores were collected prospectively. All patients underwent preoperative radiographs and magnetic resonance imaging confirming an unstable OCD fragment as well as postoperative radiographs at regular intervals. Indications for ORIF of the OCD fragment were hip pain and mechanical symptoms with radiographic evidence of LCPD and a magnetic resonance imaging demonstrating an OCD fragment of the femoral head. Osteochondral fragment instability was confirmed intraoperatively. Preoperative and postoperative physical examination findings were documented. All patients failed a course of nonsurgical treatment (activity modification, anti-inflammatories, and physical therapy). RESULTS: From a total of 64 consecutive patients treated with hip preservation surgery for LCPD, 7 patients with symptomatic OCD secondary to LCPD were treated with surgical hip dislocation and ORIF of the femoral head osteochondral fragment. OCD size lesion ranged from 200 to 625 mm. All patients reported marked clinical improvement, with resolution of both pain and mechanical symptoms. Radiographs at final follow-up demonstrated complete osteochondral fragment healing without implant failure. Mean follow-up was 4.6 years (range, 1.1 to 7.4 y). There was a significant postoperative improvement in measured internal rotation in flexion (5.0±5.0 to 16.4±9.8; P=0.02). Modified Harris Hip Score markedly improved from baseline to final follow-up (47.8 to 82.7; [INCREMENT]34.9; minimal clinically important difference, 11; P=0.002), with all patients meeting minimal clinically important difference for modified Harris Hip Score. There were no complications and no progression of osteoarthritis in all patients at final follow-up. CONCLUSIONS: We have demonstrated both predictable radiographic healing and marked clinical improvement following ORIF of symptomatic post-Perthes OCD lesions. We advocate ORIF for symptomatic osteochondral lesions as a first-line surgical treatment for these patients due to the advantages of native osteochondral tissue preservation, predictable healing, and marked clinical improvement. LEVEL OF EVIDENCE: Level IV-case series.

The Pattern of Acetabular Cartilage Wear Is Hip Morphology-dependent and Patient Demographic-dependent.

BACKGROUND: Acetabular cartilage damage has been described in patients with femoroacetabular impingement (FAI). However, most reports of articular cartilage damage in hip FAI have been focused on the acetabular cartilage and derived from single-center, retrospective studies of relatively small patient cohorts. Identifying patterns of articular cartilage wear is important in patient selection, treatment prognosis, and determining whether patterns of intraarticular cartilage wear are secondary to abnormal hip morphology. Using a multicenter, observational cohort, we sought to determine whether there was a specific pattern of cartilage wear across acetabular and femoral articular cartilage among patients with symptomatic FAI. QUESTIONS/PURPOSES: (1) Is there is a specific pattern of cartilage wear in the acetabulum and femoral head, assessed during hip arthroscopy, in cam FAI, pincer, and mixed-type hip pathologies? (2) Are there specific patterns of cartilage wear associated with duration of symptoms, age, and/or body mass index (BMI)? METHODS: A multicenter observational cohort and a hip preservation database from a senior author were used to identify 802 patients who underwent hip arthroscopy for the treatment of symptomatic FAI. The diagnosis of cam, pincer, or mixed-type FAI was determined by each treating surgeon at each institution using the minimum basic criteria of pain in the affected hip for a period of > 3 months, hip ROM, and radiographic findings. Acetabular and femoral head cartilage lesions were classified arthroscopically by location and severity for each group (cam, pincer, or mixed FAI). Cartilage wear was classified using the Beck classification and defined as cartilage lesions greater than Grade 1 (normal macroscopically sound cartilage). The assessment of cartilage wear was performed arthroscopically by experienced hip preservation surgeons who are a part of ANCHOR, a multicenter group that uses a longitudinally maintained database to investigate issues related to hip preservation surgery. Clinical characteristics, radiographic findings, and acetabular and femoral head damage by location and severity of wear were reported based on patient diagnoses of cam (n = 472), mixed (n = 290), and pincer (n = 40) FAI hip pathologies. Wald chi-square tests were used to test for differences in the presence of wear in each cartilage quadrant across hip pathologies, duration of symptoms, age, and BMI. One-way analysis of variance tests were used to test for differences in average grade of wear in each cartilage quadrant across hip pathologies, duration of symptoms, age, and BMI. A bivariate logistic regression model was used to identify factors independently associated with the presence of cartilage wear in the acetabulum and femoral head. Acetabular cartilage wear was present in 743 of 802 patients (93%) in the cohort. Femoral head cartilage wear was observed in only 130 (16%). RESULTS: We found significant associations between acetabular patterns of wear and FAI hip pathologies; specifically, we observed more frequent and severe debonding of acetabular cartilage in patients with symptomatic cam (93%, 1.7 ± 1.1 grade) and mixed (97%, 1.7 ± 1.2 grade) FAI compared with Pincer (75%, 1.5 ± 0.9 grade) FAI hip pathologies (p < 0.001). Superolateral peripheral cartilage lesions occurred more frequently and with greater severity in patients with cam (90% [416 of 472] prevalence, 3.1 ± 1.1 grade) and mixed (91% [260 of 290] prevalence, 3.1 ± 1.1 grade) FAI than in pincer (60% [24 of 40] prevalence, 2.2 ± 1.1 grade) FAI hip pathologies (p < 0.0001). Conversely, patients with pincer FAI most commonly demonstrated cartilage lesions with an even distribution at the anterior and superolateral acetabular rim: 64% (25 of 40) (mean grade 2.1 ± 1.0) and 60% (24 of 40) mean grade 2.2 ± 1.1, respectively. Age was associated with increased presence of wear in both the acetabulum (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.2-1.7; p = 0.005) and femoral head (OR, 1.08; 95% CI, 1.6-1.1; p < 0.001). BMI was associated with a greater presence of wear only in the femoral head (OR, 1.1; 95% CI, 1.2-1.1; p = 0.002). Specifically, compared with patients with a BMI < 30 kg/m, patients with a BMI ≥ 30 kg/m presented with more frequent and more severe lesions in the posterior peripheral acetabular rim (42% [47 of 117] versus 26% [171 of 677], p = 0.0006; grade 1.9 ± 1.3 versus grade 1.4 ± 0.9, p < 0.001), the anterolateral femoral head (22% [20 of 117] versus 9% [60 of 67], p = 0.006), and the anteromedial femoral head (15% [16 of 117] versus 6% [39 of 677], p = 0.002; grade 1.3 ± 0.8 versus grade 1.1 ± 0.6, p = 0.04). In general, we found that older patients (≥ 50 years old) presented with more frequent and more severe lesions in both the acetabulum and femoral head. We found no association between hip pathology and cartilage wear patterns in the examined femoral heads. CONCLUSIONS: Hip morphology affects the pattern of acetabular cartilage wear. More frequent and severe cartilage lesions were observed in patients with symptomatic FAI cam and mixed-type hip pathologies. Surgical attempts to restore normal anatomy to avoid FAI should be performed to potentially improve long-term joint homeostasis. Increasing age is an independent risk for cartilage wear in both the acetabulum and femoral head. Additionally, increased BMI is an independent risk factor for cartilage wear in the femoral head. In the future, prospective studies should provide further insight into the pathomechanics of early degenerative changes associated with hip FAI deformities. LEVEL OF EVIDENCE: Level III, prognostic study.

Editorial Commentary: The Hip-Spine Connection in Patients Undergoing Hip Arthroscopy: Should We Learn From Total Hip Replacement and Counsel Patients Differently If They Have Had Previous Back Surgery?

Disorders of the adult hip and spine are common, and there is evidence that there is a hip-spine connection in patients with hip femoroacetabular impingement (FAI). Many reports have shown that patients undergoing lumbar fusion and subsequent total hip arthroplasty have a higher risk of complications and worse outcomes following total hip arthroplasty. However, there has been a paucity of research on the effect of a history of lumbar spine surgery in patients undergoing hip arthroscopy for the treatment of FAI. Variations in lumbar lordosis, pelvic incidence, tilt, and sacral slope may modify the degree of FAI, symptoms, and patient-reported outcomes following hip arthroscopy. In the future, we should continue our efforts to better understand the impact that limited range of motion in the spine has in joint mechanics of the hip and the possibility of affecting patient-reported outcomes after hip arthroscopy. Future studies incorporating novel imaging technology, such as EOS, may be an objective way of assessing the effect of abnormal spine-pelvic function in patients with hip FAI.

Proceedings of the signature series symposium "cellular therapies for orthopaedics and musculoskeletal disease proven and unproven therapies-promise, facts and fantasy," international society for cellular therapies, montreal, canada, may 2, 2018.

The Signature Series Symposium "Cellular Therapies for Orthopaedics and Musculoskeletal Disease Proven and Unproven Therapies-Promise, Facts and Fantasy" was held as a pre-meeting of the 26th International Society for Cellular Therapy (ISCT) annual congress in Montreal, Canada, May 2, 2018. This was the first ISCT program that was entirely dedicated to the advancement of cell-based therapies for musculoskeletal diseases. Cellular therapies in musculoskeletal medicine are a source of great promise and opportunity. They are also the source of public controversy, confusion and misinformation. Patients, clinicians, scientists, industry and government share a commitment to clear communication and responsible development of the field. Therefore, this symposium convened thought leaders from around the world in a forum designed to catalyze communication and collaboration to bring the greatest possible innovation and value to patients with musculoskeletal conditions.

Does Severity of Acetabular Dysplasia Influence Clinical Outcomes After Periacetabular Osteotomy?-A Case-Control Study.

BACKGROUND: Detailed characterization of factors influencing post-periacetabular osteotomy (PAO) outcome could guide treatment offered. METHODS: Using a prospective, multicenter database of PAOs, 61 hips/patients (51 females) with lesser dysplasia (acetabular index < 15° and lateral center-edge angle > 15°) were case-control matched for age, gender, body mass index, Tönnis grade, and joint congruency (P = .6-.9) with a "comparison group" of pronounced dysplasia (n = 183), aiming to assess whether severity of acetabular dysplasia has an effect on outcome following PAO and/or the ability to achieve desired acetabular correction. RESULTS: At 4 ± 1.5 years, no differences in complication or reoperation rates were detected between the groups (P = .29). Lesser dysplastic hips had inferior Hip Disability and Osteoarthritis Outcome Score, both preoperatively (52 vs 59) and postoperatively (73 vs 78); however, similar improvements were seen. Among the lesser dysplastic hips, those that required a femoral osteochondroplasty at PAO had significantly inferior preoperative Hip Disability and Osteoarthritis Outcome Score (48 ± 18). Increased ability to achieve optimum correction was seen (80% vs 59%, P = .4) in lesser dysplasia. CONCLUSION: A PAO is safe and efficacious in the treatment of lesser dysplasia. Further study on the identification of the optimum treatment modality for the mildly dysplastic hips with cam deformity is required.

Acetabular Focal Chondral Lesions Are Not Associated With Worse Outcomes After Periacetabular Osteotomy: A Matched Group Analyses.

BACKGROUND: The purpose of this study was to assess the outcomes of patients who underwent combined hip arthroscopy and periacetabular osteotomy with acetabular focal chondral defects and compare these outcomes with a group of patients without focal chondral defects. METHODS: A retrospective review looking at patients who underwent hip arthroscopy and/or periacetabular osteotomy was performed. Minimum 2-year follow-up, Tönnis grade 0-1, and a Beck chondromalacia stages 4-5 were included. Twenty-eight hips met inclusion criteria. These patients were then matched 1:1 and compared. RESULTS: The average acetabular chondral defect size was 144.3 mm2 ± standard deviation 116.2. Postoperative, modified Harris Hip Score, Hip Disability and Osteoarthritis Outcome Score, and University of California Los Angeles scores were similar between groups (P = .382, P = .755, P = .763, respectively). At the last follow-up, Tönnis grade was similar between groups (P = .552). No association between having a defect and increased risk of failure was noted (hazard ratio 1.35 [95% CI 0.43-4.24], P = .607). CONCLUSION: We found that patients with focal chondral defects did similar to a comparison group of patients without chondral defects.

A Comparison of the Outcomes for Cartilage Defects of the Knee Treated With Biologic Resurfacing Versus Focal Metallic Implants.

PURPOSE: To compare the results of focal metallic resurfacing with biologic procedures in patients more than 35 years of age with isolated, full thickness defects of the femoral condyle. METHODS: A total of 61 patients met the selection criteria resulting in 30 patients treated with biological procedures, including debridement, microfracture, osteochondral autograft transplantation, osteochondral allograft, and autologous chondrocyte implantation (BIO group), and 32 patients treated with focal metallic resurfacing (CAP group). The BIO and CAP groups were matched according to treatment location, defect grade and size, and age profile. Outcomes included Western Ontario and McMaster Osteoarthritis Index (WOMAC), Short Form-12, and satisfaction. The primary combination endpoint was determined as a 20% improvement (minimum clinically important difference-20) on WOMAC pain and function at 2 years and no additional index lesion-related surgical intervention. Safety and effectiveness were also reported. RESULTS: Thirty patients in the BIO group (mean age of 44.6, range 35-64) had an average follow-up of 2.6 years and 32 patients in the CAP group (mean age 47.9, range 37-68) were followed for 2.0 years. Fifty-three percent in the BIO group and 75% in the CAP group achieved success per the endpoint definition. The mean total WOMAC score improved significantly for both groups (BIO: 57-78; P < .001) (CAP: 41-86; P < .001). The physical component score (Short Form-12 PCS) improved significantly in the CAP group only (30-36.4; P < .001). Good to excellent patient satisfaction was achieved by 80% in BIO and 91% in CAP. There were 4 secondary procedures on the index lesion in the BIO group and 2 in the CAP group. CONCLUSIONS: Careful patient selection can achieve high satisfaction rates with both biological and focal metal resurfacing procedures for the treatment of isolated focal chondral lesions of the femoral condyle in the knee. Focal metallic resurfacing results in similar clinical outcomes and provides excellent success rates at short-term follow-up. LEVEL OF EVIDENCE: Level III comparative study.

Innovations in Joint Preservation Procedures for the Dysplastic Hip "The Periacetabular Osteotomy".

The Bernese periacetabular osteotomy is an effective treatment for symptomatic developmental dysplasia in the prearthritic young adult hip. Refinements in the periacetabular osteotomy technique and perioperative management have markedly improved the clinical outcomes and recovery in these patients. We will review the clinical presentation of acetabular dysplasia, indications for surgery, perioperative management, and contemporary refinements in technique including refined acetabular reduction, adjunctive hip arthroscopy, femoral head-neck osteochondroplasty, femoral procedures, and rapid recovery protocols. In well-selected patients, this reconstructive osteotomy should be considered safe and effective in alleviating pain and improving hip function in patients with symptomatic acetabular dysplasia.

Evidence for the Use of Cell-Based Therapy for the Treatment of Osteonecrosis of the Femoral Head: A Systematic Review of the Literature.

BACKGROUND: Cell-therapy has been promoted among the therapeutic arsenal that can aid in bone formation and remodeling, in early stages of osteonecrosis of the femoral head (ONFH). The purpose of this systematic review was to assess the evidence supporting the (1) clinical efficacy; (2) structural modifying effect, as evaluated radiographically; (3) revision rates; and (4) safety of cell-therapy for the treatment of ONFH. METHODS: A systematic review was performed including studies with a level-of-evidence of III or higher. A total of 1483 articles were screened. Eleven studies met the criteria for inclusion in this review (level-of-evidence: 6 level-I, 1 level-II, and 4 level-III), including 683 cases of ONFH. RESULTS: All 10 studies that reported patient-reported outcomes showed improved outcomes in the cell-therapy groups compared with the control group. Overall, 24.5% (93/380 hips) that received cell-therapy showed radiographic progression compared with 40% (98/245 hips) in the control group. Nine of 10 studies that reported failure rates showed a lower total hip arthroplasty conversion rate in the cell-therapy group 16% (62/380 hips) compared with the control group 21% (52/252 hips). There was a low complication rate (<3%) with no major adverse effects. CONCLUSION: Cell-therapies for the treatment of ONFH have been reported to be safe and suggest improved clinical outcomes with lower disease progression rate. However, there was substantial heterogeneity in the included studies, and in the cell-based therapies used. Specific clinical indications and cell-therapy standardization are required because studies varied widely with respect to cell sourcing, cell characterization, adjuvant therapies, and assessment of outcomes.

Analysis of Cell Therapies Used in Clinical Trials for the Treatment of Osteonecrosis of the Femoral Head: A Systematic Review of the Literature.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) is associated with regional loss of cells within bone, often resulting in pain and mechanical collapse. Our purpose was to analyze the cell-therapies used in clinical trials for the treatment of ONFH with regard to (1) cell-sources, (2) collection techniques, (3) cell-processing, (4) qualitative and quantitative characterizations, and (5) delivery methods. METHODS: A systematic review of the current literature on the use of cell therapies for the treatment of ONFH was performed. Studies with a level-of-evidence III or higher were evaluated. A total of 1483 articles were screened. Eleven studies met the criteria to be included in this review. RESULTS: Ten studies used bone-marrow, and 1 study used blood as the cell-source. Nine studies used freshly isolated tissue-derived nucleated cells from bone-marrow, mixed bone marrow-derived nucleated cells, 1 study used mixed blood-derived nucleated cells, and 1 study used culture-expanded cells derived from bone marrow aspirate. Cell dose varied from 2-million to 3-billion cells. Qualitative cell characterization of injected cells using surface markers was done by 5 studies using CD34. Two studies assayed the cell-population using a colony-forming-unit assay. CONCLUSION: There is a lack of standardization with respect to the quantitative and qualitative characterization of methods for cell-harvest, cell-processing, and cell-transplantation/delivery. Cell-therapy holds promise as a means of restoring local cell populations that are made deficient because of injury or disease. However, the orthopedic community and patients will benefit greatly by a greater investment in blinded, randomized, controlled trials and clinical effectiveness trials that embrace rigorous standards.

Biological treatment of the knee with platelet-rich plasma or bone marrow aspirate concentrates.

- Knee pathologies including focal cartilage injuries, osteoarthritis (OA), and ligament injuries are common. The poor regeneration and healing potential of cartilage has led to the search for other treatment modalities with improved healing capacity. Furthermore, with an increasing elderly population that desires to remain active, the burden of knee pathologies is expected to increase. Increased sports participation and the desire to return to activities faster is also demanding more effective and minimally invasive treatment options. Thus, the use of biologic agents in the treatment of knee pathologies has emerged as a potential option. Despite the increasing use of biologic agents for knee pathology, there are conflicting results on the efficacy of these products. Furthermore, strong data supporting the optimal preparation methods and composition for widely used biologic agents, such as platelet-rich plasma (PRP) and bone marrow aspirate concentrate (BMAC), largely remain absent from the literature. This review presents the literature on the most commonly employed biologic agents for the different knee pathologies.

The Role of Hip Arthroscopy in Investigating and Managing the Painful Hip Resurfacing Arthroplasty.

PURPOSE: To determine the safety and efficacy of hip arthroscopy performed in the peripheral compartment as a diagnostic and therapeutic treatment option for patients with hip pain after hip resurfacing surgery. METHODS: Indications for hip arthroscopy after hip resurfacing included patients with a symptomatic hip-resurfaced arthroplasties who did not respond to nonoperative treatment. Patients who underwent a hip arthroscopy after a painful hip resurfacing were included with a minimum of 1 year follow-up. Subgroup analysis was performed according to whether an established diagnosis was made before arthroscopic intervention or not. Subjective measures were based on Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, and results were calculated and analyzed. RESULTS: We included 68 patients (26 male [38%] and 42 female [62%]) who underwent subsequent hip arthroscopy from a population of 978 consecutive hip-resurfaced arthroplasties performed between 1999 and 2010. The average age was 58 (range, 37 to 78 years). The mean follow-up after hip arthroscopy was 3.4 years (range, 12 months to 5.8 years). Patients who had an established diagnosis (n = 41) before hip arthroscopy showed statistical improvement in their WOMAC scores (7 to 2, P < .001). Only 3 (7%) of these 41 patients failed and were converted to a total hip replacement (THR); however, patients who did not have an established diagnosis (n = 27) before undergoing hip arthroscopy showed statistical worsening of the WOMAC (15 to 21, P = .002). Ten (37%) of these 27 patients without a diagnosis failed and needed to be converted to a THR. A significant correlation was found between the collections found on ultrasound (psoas bursa and/or in the hip joint) and the need for synovectomy (P = .01). The overall revision rate to THR after hip resurfacing in our group of patients was 1.3% (n = 13). Female patients were more likely to require postresurfacing hip arthroscopy with 42 (60%) female to only 26 (40%) male patients undergoing this procedure. In our study population, 70% (14/21, P < .05) of patients with hip pain caused by severe metal synovial reaction or metal-on-metal reaction were women. A total of 5 (7%) patients had minor-to-mild complications after hip arthroscopy. CONCLUSIONS: Hip arthroscopy is a safe surgical treatment option for those patients with a painful hip resurfacing arthroplasty. Having an accurate diagnosis before hip arthroscopy improves the likelihood a good outcome. LEVEL OF EVIDENCE: Level IV - therapeutic case series.

Can hip arthroscopy be performed with conventional knee-length instrumentation?

PURPOSE: The purpose of this study was to determine whether hip arthroscopy can be performed using conventional knee-length arthroscopy instrumentation. METHODS: We included 116 consecutive hip arthroscopies (104 patients) in this study. Age, side of surgery, height (in inches), weight (in pounds), body mass index (BMI), and a subjective assessment of body type (1, muscular; 2, somewhat overweight; 3, overweight; 4, thin; and 5, normal weight) were recorded. The depth from the skin at 2 portal sites to 3 commonly accessed positions (12 o'clock, 3 o'clock, and acetabular fossa) was assessed using a guide with marked notches (in millimeters). Subgroup analysis was performed according to BMI and subjective biotype for each patient. RESULTS: We included 104 patients with a mean age of 35 years (range, 14 to 55 years). As categorized by BMI, 60% of patients were normal weight, 22% were overweight, 16% were obese, and 2% were underweight. All but 8 procedures were performed with conventional knee-length arthroscopic shavers and burrs. The 8 procedures that needed additional hip instrumentation were performed in patients who required ligamentum teres debridement or those with iliopsoas tenotomy. Overall, the distance from skin to socket was less than 11 cm at the 12-o'clock and 3-o'clock positions from both the anterolateral and anterior portals. Obese and overweight patients had statistically longer distances from skin to socket at all 3 measurement points compared with underweight and normal-weight patients. Considering biotype, the distances from skin to socket in underweight, normal-weight, and muscular patients were all equal to or less than 10 cm. CONCLUSIONS: The distance from skin to socket at the 12- and 3-o'clock positions is less than 11 cm, suggesting that hip arthroscopy can be performed with conventional knee-length instrumentation devices. In obese and overweight patients and patients requiring ligamentum teres debridement or iliopsoas tendon release, specific hip arthroscopic tools should be available. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Revision of anterior cruciate ligament reconstruction with allografts in patients younger than 40 years old: a 2 to 4 year results.

PURPOSE: The purpose of this study is first to report the outcomes, at 4 years follow-up, in revision ACL surgery using allografts in patients younger than 40 years old, and then compared soft tissue allografts to bone tendon allografts. METHODS: This retrospective study included 47 patients who underwent ACL revision surgery with fresh-frozen allografts. Patellar tendon allograft or tibialis anterior allograft was used. Twenty-seven patients undergoing ACL revision with patellar tendon allograft were compared retrospectively with twenty-two patients undergoing the same procedure with soft tissue tibialis anterior allograft. Lysholm, IKDC, and KT-1000 values were obtained preoperatively and postoperatively. RESULTS: The average patient follow-up was 4.6 years (±2.5). The mean age at time of the revision was 34 years old (±6.3). Overall, patients reported the overall condition of their knee as excellent or good in 85% of the patients (10 excellent, 33 good). Based on their experience, 85% would have the surgery again if they had the same problem in the other knee. Both subgroups experienced significant improvement in Lysholm, IKDC, and KT-1000 values, with no difference found between groups at final follow-up. CONCLUSION: Revision ACL with allografts has excellent and good results in 85% of patients younger than 40 years old. No statistical difference was seen between soft tissue (tibialis anterior) and patellar tendon allograft. LEVEL OF EVIDENCE: IV.