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Background: The limb symmetry index (LSI) is a measure comparing strength and functional movement between the surgical and nonsurgical limbs, used after anterior cruciate ligament reconstruction (ACLR) to guide rehabilitation and assess return-to-sport readiness. With increasing use of the quadriceps tendon autograft (QT-ACLR), limited data exist on whether the LSI score correlates with patient-reported outcome measures (PROMs). Hypothesis/Purpose: To evaluate the predictive value of postoperative strength and functional LSI tests at 3, 6, and 9 months for short-term PROMs, determine Patient Acceptable Symptom State (PASS) thresholds, and assess differences based on PASS achievement. It was hypothesized that quadriceps strength LSI score would more strongly predict 2-year PROMs than hamstring strength LSI score, and that higher 9-month isokinetic quadriceps LSI scores would be associated with higher International Knee Documentation Committee (IKDC) and Lysholm scores. Study Design: Case series; Level of evidence, 4. Methods: Patients undergoing primary QT-ACLR from 2021 to 2024 with LSI testing during rehabilitation (isometric and isokinetic lower extremity strength, Y-Balance, hop testing) and no revision or additional knee surgery were included. The LSI score was assessed at 3, 6, and 9 months, and PROMs, including Lysholm and IKDC scores, were collected at a mean follow-up of 2.0 ± 0.7 years. Multivariable linear regression was used to evaluate associations between LSI measures and PROMs after adjusting for age, sex, and body mass index (BMI). Receiver operating characteristic analysis was used to determine PASS thresholds. Results: A total of 100 knees in 100 patients (mean age, 25.3 ± 11.2 years; BMI, 25.9 ± 6.5 kg/m 2 ; 52% male) were included. Quadriceps and hamstring strength and functional performance progressively improved from 3 to 9 months, with the LSI score reaching 77% to 81% for quadriceps strength and 98% to 100% for hamstring strength by 9 months postoperatively. At a mean follow-up of 2.0 ± 0.7 years, the mean satisfaction score was 8.4 of 10, the Lysholm score was 90.7, and the IKDC score was 77.8. Linear regression, adjusted for age, sex, and BMI, demonstrated that 3-month isometric quadriceps LSI score had a strong effect on IKDC score, explaining substantial variance (β = 3.9; adjusted R 2 [Adj R 2 ] = 0.36; P < .03); 6-month isokinetic quadriceps and hamstrings showed moderate but significant effects (β = 2.9-3.7; Adj R 2 = 0.13-0.17; P < .05) on IKDC score; and 9-month fast quadriceps had a strong effect explaining substantial variance in Lysholm and IKDC scores (β = 3.9-4.7; Adj R 2 = 0.34-0.35; P ≤ .003). Lysholm and IKDC scores correlated with satisfaction and accurately discriminated PASS thresholds (area under the curve, 0.927-0.937; P < .001). Patients achieving the IKDC PASS demonstrated higher LSI scores across time points and all PROMs. Conclusion: After QT-ACLR, strength-associated LSIs were independently associated with PROMs at a mean 2-year follow-up, after adjusting for age, sex, and BMI. Early isometric quadriceps strength at 3 months predicted higher 2-year IKDC scores, with PASS achievers generally attaining a 60% to 70% LSI score by 3 months. Isokinetic quadriceps strength at 9 months predicted both IKDC and Lysholm scores. These findings highlight the importance of early quadriceps strength recovery and the value of LSI measures in predicting PROMs and informing early rehabilitation.

Purpose To assess the reliability, predictability, and discriminative capacity of 3 anatomic measurements, tibial tubercle‐trochlear groove (TT‐TG), tibial tubercle‐posterior cruciate ligament, and patellar tendon‐lateral trochlear ridge (PT‐LTR), where PT‐LTR may offer a complementary approach to assessing recurrent patellofemoral instability (PFI) risk. Methods Patients diagnosed with PFI before primary patellofemoral stabilization surgery at a single institution between 2022 and 2024 were included. A control group without PFI was propensity matched 1:1 for age, sex, and laterality. Magnetic resonance images were evaluated to measure TT‐TG, tibial tubercle‐posterior cruciate ligament, and PT‐LTR. A priori power analysis determined the cohort size. Statistical analyses compared differences between the PFI and control groups with Student t‐tests, receiver operating characteristic analyses, and area under the curve with resultant sensitivity, specificity, and an optimal cutoff. Results Patients included 50 knees with PFI (28 women, 22 men; mean age 18 ± 5 years). The control group included 50 knees (27 women, 23 men; mean age 18 ± 4 years). Excellent inter‐ and intra‐rater reliability (intraclass correlation coefficient > 0.7) was shown for TT‐TG and PT‐LTR in the PFI and control groups. The distances for TT‐TG, tibial tubercle‐posterior cruciate ligament, and PT‐LTR were significant predictors ( P ≤ .025) of PFI. The average PT‐LTR distance difference for the PFI and control groups was 7.0 mm ( P < .001). PT‐LTR showed an area under the curve of 0.80 and, when ≥4.6 mm, was 66% sensitive and 92% specific for PFI. Conclusions The PT‐LTR distance is a reliable and discriminative metric for identifying PFI in both pediatric and adult populations. A PT‐LTR cutoff value of 4.6 mm showed diagnostic discrimination and substantially high specificity for recurrent PFI, indicating strong ability to identify patients with instability. Level of Evidence Level III, retrospective case control study.

Purpose To evaluate implantation rates, time to implantation, and predictors of implantation following matrix‐induced autologous chondrocyte implantation (MACI) biopsy for knee chondral defects. Methods Patients undergoing MACI biopsy or implantation for symptomatic knee chondral defects from 2017 to 2024 at a single institution were reviewed. At a minimum 1‐year follow‐up, the decision to proceed with implantation, recurrent symptoms, complications, and reoperations were assessed. Kaplan‐Meier analysis estimated time to implantation, and multivariable logistic regression identified predictors of MACI implantation. Results A total of 208 knees in 202 patients (mean age 28.0 ± 10.9 years, range 11‐59) underwent MACI biopsy for 243 chondral defects (patella [38%], femoral condyle [34%], and trochlea [26%]). At a mean follow‐up of 4.3 years (range 1.0‐8.3), 64 knees (31%) proceeded to second‐stage MACI implantation. Among 144 knees not implanted, 87 (60%) reported symptom improvement, and 26 (18%) had persistent symptoms. The remaining 22% did not undergo implantation due to another cartilage procedure, insurance denial, or pending scheduling. Patients who underwent biopsy at the home institution had a shorter time from biopsy to implantation compared with those biopsied at outside institutions (6.1 vs 13.1 months, P = .001). Median time to implantation was 9.4 months (95% confidence level: 7.2‐12.2) for home biopsies. Lower body mass index was associated with progression to implantation after adjusting for covariates (odds ratios 0.92, P = .019). Patients implanted within 4 months had larger chondral defects (4.0 vs 3.0 cm 2 , P = .045). At a mean 4.1‐year follow‐up, 6 patients (8%) experienced postoperative complications, including 3 (4%) who required revision chondroplasty. Conclusions MACI biopsy for knee chondral defects resulted in approximately one‐third of patients proceeding to MACI implantation, at a median of 9.4 months after biopsy. Lower body mass index was associated with higher likelihood of progression to implantation, larger chondral defects with earlier implantation, and among patients who did not proceed to implantation, approximately 60% reported symptom improvement following concomitant chondroplasty at the time of biopsy. Level of Evidence Level IV, retrospective case series.

Background: Dancers are at risk of femoroacetabular impingement (FAI) owing to supraphysiologic range of motion and associated demands placed on their hips. There remains a paucity of literature on midterm outcomes in dancers who undergo primary arthroscopy and labral repair for FAI. Purpose: To determine the rate of return to dance and patient-reported outcome measures in competitive dancers after hip arthroscopy with labral repair for FAI with minimum 2-year follow-up. Study Design: Case series; Level of evidence, 4. Methods: This study included dancers with FAI undergoing primary hip arthroscopy with labral repair from 2010 to 2022. Patient-reported outcome measures were collected at 2-year minimum follow-up: modified Harris Hip Score (overall, activities of daily living, gait, pain), Hip Outcome Score (activities of daily living, sports-specific subscale), Tegner Activity Scale, visual analog scale for pain, and surgery satisfaction. Patients were evaluated for preoperative radiographic measurements, postoperative return to sport, and revision surgery. Return to dance was evaluated. Results: Thirty-seven dancers were followed for a mean 7.4 years (range, 3.2-12.2) postoperatively (36 female and 1 male; mean ± SD age, 21 ± 7 years; mean body mass index, 23.3 ± 4.5). All outcome scores significantly improved postoperatively as compared with preoperatively ( P ≤ .037). Twenty dancers (71%) returned to dance. Of those who returned to dance, 17 (85%) returned to sport at the same or higher level as compared with the preoperative level. At final follow-up, 45% of dancers who initially returned to dance continued to dance. Of the dancers who no longer participated in dance at final follow-up, 7 (65%) quit dancing for nonhip-related reasons. Mean surgery satisfaction (0-10) at final follow-up was 7.1. Four patients (10%) underwent revision hip arthroscopy with revision labral repair. Conclusion: Hip arthroscopy with labral repair in dancers results in sustained improvements in function and pain at minimum 2-year follow-up. Most dancers return to their prior levels of dance, and nearly half remain active several years later. Notably, discontinuation of dance was often unrelated to hip symptoms, underscoring the importance of counseling patients on clinical and lifestyle factors influencing return to sport.

Purpose To prospectively investigate subjective anterior groin pain, patient‐reported outcome measures, complications, reoperation rates, and hip flexion strength after arthroscopic iliopsoas fractional lengthening. Methods From 2023 to 2025, patients with persistent groin pain after total hip arthroplasty refractory to conservative management undergoing arthroscopic iliopsoas fractional lengthening were prospectively identified at 2 tertiary referral centers. Pre‐ and postoperative outcomes at a minimum 6‐month follow‐up including the Visual Analog Scale, Tegner activity scale, Single Assessment Numeric Evaluation, and subjective anterior groin pain and hip flexion strength were analyzed. Results Fifty‐nine hips in 56 patients were included (age: 64.9 ± 9.8 years, 59% women, body mass index: 30.0 ± 5.8 kg/m 2 ) and followed for 10.0 ± 6.9 months postoperatively (range: 4‐25 months). Patients experienced significant ( P < .001) postoperative improvements in the Visual Analog Scale at rest (1.4 ± 2.2 vs 2.8 ± 2.1), Visual Analog Scale with use (3.0 ± 2.9 vs 7.8 ± 1.8), Tegner activity scale (2.8 ± 1.2 vs 2.0 ± 1.0), and Single Assessment Numeric Evaluation score (73.8 ± 22.5 vs 47.7 ± 22.2). Postoperative surgical satisfaction was 8.0 ± 2.7 (scale: 0‐10). Nearly 90% of patients reported feeling much or slightly better regarding their anterior groin pain postoperatively at 2‐week (91%), 6‐week (88%), 3‐month (91%), and final follow‐up (92%). Regarding hip flexion strength, ≥66% reported feeling much or slightly better at 2‐week (73%), 6‐week (95%), 3‐month (89%), and final follow‐up (66%). Three hips (6%) underwent reoperation at the final follow‐up (1 acetabular screw removal with open revision release, 1 revision total hip arthroplasty for loosening, and 1 two‐stage exchange for nonacute periprosthetic joint infection). Conclusions Nearly 90% of patients who underwent arthroscopic iliopsoas fractional lengthening after primary total hip arthroplasty reported improved anterior groin pain, whereas two‐thirds reported increased subjective hip flexion strength throughout the follow‐up. Of note, clinically meaningful improvement in pain at rest was achieved by 50% of patients based on cohort‐specific minimal clinically important difference criteria. Level of Evidence Level IV, retrospective therapeutic case series.

Background: Acetabular overcoverage (pincer morphology) has been suggested to be both a source of pain and dysfunction and potentially protective against osteoarthritic change. Purpose: To compare the minimum 5-year clinical outcomes of patients undergoing primary hip arthroscopic labral repair with a lateral center edge angle (LCEA) of ≥40° as compared with nondysplastic controls with an LCEA of 25° to 40°. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective review was performed to identify all patients who underwent primary hip arthroscopic labral repair between 2009 and 2019 at a single academic institution. Patients with an LCEA of ≥40° (pincer) were propensity-matched to nondysplastic controls with an LCEA of 25° to 40° on a 1-to-2 basis by sex, age, body mass index, and surgery year. Patient-reported outcome measures (PROMs)—including visual analog scale, Tegner activity score, modified Harris Hip Score, International Hip Outcome Tool (iHOT-12), and Hip Outcome Score were analyzed—as were reoperations and conversions to total hip arthroplasty (THA). Results: A total of 55 patients with pincer morphology (preoperative LCEA: 41.9°± 2.1°) were matched to 110 nondysplastic controls (LCEA: 31.2°± 4.1°), resulting in a total of 165 hips in 163 patients (67% women, mean age: 37.7 ± 9 years). Pincer patients were corrected to a mean postoperative LCEA of 38.7°± 4.1º ( P < .001), with 22 pincer patients having residual overcoverage; namely, a postoperative LCEA ≥40° (range, 40°-45.8°). There were no differences between cohorts regarding intraoperative characteristics—including femoral and acetabular Outerbridge grade—as well as capsulotomy type and the presence of capsular repair ( P ≥ .210). At a mean 8-year follow-up (range, 5.1-13.2), there was no difference in any postoperative PROMs between pincers and controls ( P ≥ .215) and no difference in PROMs between patients with residual overcoverage and pincer patients with a postoperatively normalized LCEA ( P ≥ .291). At final follow-up, 4 patients in the pincer cohort (7%) and 21 controls (19%) converted to THA ( P = .046). Conclusion: Patients with lateral acetabular overcoverage demonstrated similar and satisfactory postoperative PROMs at a minimum 5-year follow-up compared with propensity-matched nondysplastic controls, regardless of whether the LCEA was corrected to <40°. Of note, nondysplastic controls demonstrated a higher rate of conversion to THA, suggesting a potentially chondroprotective role for acetabular overcoverage.

Abstract Femoroacetabular impingement with cam morphology that fails nonoperative management can be addressed with hip arthroscopy and cam resection. There exists a wide variation of cam morphology due to various etiologies that can make some cam lesions more challenging to address. A thorough preoperative evaluation and the utilization of a variety of intraoperative techniques can allow for adequate arthroscopic resection of these otherwise challenging cam lesions. In this technique video, we describe a systematic approach for the preoperative assessment of femoroacetabular impingement due to a cam lesion and consideration of different approaches for arthroscopic resection based on cam‐specific morphology.

Hip arthroscopy is an increasingly common procedure to treat intra‐articular conditions such as labral tears and femoroacetabular impingement. With the increase in frequency of such procedures, so too are revision arthroscopic hip procedures. Capsular repair in the setting of revision hip arthroscopy can be challenging due to the presence of adhesions and scar tissue formation that obscure tissue planes, suboptimal quality of residual capsular tissue, and the presence of capsular tissue defects. This technical note aims to describe the key surgical principles and considerations of revision hip capsular closure.

Background: Arthroscopic treatment of excessive acetabular coverage with pincer morphology or coxa profunda can be challenging. In patients with excessive acetabular coverage with nondistractible hips, an outside-in capsuolotomy can be considered to gain safe and efficient intra-articular access to the hip. Indications: The indications for an outside-in capsulotomy include patients with acetabular retroversion, a lateral center-edge angle >40°, coxa profunda or protrusio, or stiff, older male patients who remain hip preservation candidates. Technique Description: The outside-in capsulotomy is performed once it is recognized that traction on the operative extremity will not provide adequate working space for safe intra-articular access. Traction is taken off the operative extremity, and an anterolateral portal is localized to the 12:00 position on the hip joint with the use of fluoroscopy. The camera is then placed in a juxta-capsular location, and a modified anterior portal is created under direct arthroscopic visualization. We then proceed with extracapsular dissection to identify the indirect head of the rectus. An outside-in capsulotomy is then performed parallel to the indirect head of the rectus, approximately 5 mm distal to its insertion on the acetabular rim. Prior to deep completion of the capsulotomy, the hip joint is flexed to 30° to protect the articular cartilage of the femoral head. Once intra-articular access is obtained, traction can be reapplied, and one can proceed with hip arthroscopy in a standard fashion. Results: This technique decreases the traction time needed, given that the capsulotomy is performed without traction applied. Additionally, the amount of force required for hip distraction is decreased once the capsuolotomy has been completed, through usual sectioning of the iliofemoral ligament. The presented technique is both safe and efficacious, with no published difference in complications as compared to standard inside-out access. A published series of patients with severe pincer morphology and lateral overcoverage who undergo hip arthroscopy with outside-in access demonstrates satisfactory postoperative improvements in patient-reported outcome measures. Discussion/Conclusion: The outside-in capsulotomy provides a means for safe access to the hip joint in otherwise limited or nondistractible hips.

Abstract Introduction Periacetabular osteotomy (PAO) is performed in the setting of hip dysplasia to increase acetabular coverage of the femoral head and improve joint biomechanics and longevity. PAO fixation is generally achieved with two or three 4.5 mm screws, as compared to the generally more substantial plate and screw constructs used in the setting of acetabular fractures or pelvic ring injuries. The purpose of this study was to evaluate postoperative changes in hip joint center medialization and lateral acetabular coverage following PAO, understanding that these radiographic measures are generally used to guide intra-operative assessment of correction. Methods A retrospective chart review of 100 consecutive PAOs during 2021-2023 at a single academic institution by four surgeons was performed. Perioperative radiographs and fluoroscopy images were evaluated to measure lateral center edge angle (LCEA), Tönnis angle, and medialization of the hip joint center. The hip joint center was measured at one-third of the diameter of the femoral head from inferior to superior, to the ilioischial line, as previously validated by Fowler and colleagues. Results One hundred PAOs in 87 patients (87% female, mean age: 23.0 years) were included. Average preoperative radiographic parameters were 19.9° for LCEA, 12.5° for Tönnis angle, and 12.6 mm for distance from the femoral head to ilioischial line. Ninety-four cases (94%) used three screws, and 6 cases (6%) used two screws for unstable fragment fixation. On immediate postoperative films, average correction was to 28.3° for LCEA, 4.9° for Tönnis angle, and 1.9 mm of pre- to postoperative femoral head medialization (p≤0.001). Patients were radiographically followed for an average of 13.3 months, with an average time to radiographic union of 7.1 months. During the course of follow-up, LCEA increased to 29.3°, Tönnis angle remained to 5.0° (p=0.47), and medialization increased to 2.7 mm (p≤0.02), suggesting further significant but clinically modest increases in lateral coverage and femoral head medialization. Conclusion While the majority of lateral acetabular coverage and femoral head medialization occurs intra-operatively at the time of PAO, patients undergo modest but statistically significant postoperative increases in lateral coverage and medialization prior to radiographic union.