Ultrasound Demonstrates Potential in Identifying Proximal Femoral Morphology Before and After Cam Resection: A Cadaveric Study.

PURPOSE: (1) To compare alpha angles measured on fluoroscopy with those measured on ultrasound pre- and postosteoplasty and (2) to determine whether ultrasound can adequately assess cam deformity correction. METHODS: Twelve full-body specimens (20 hips) were analyzed. Images using fluoroscopy and ultrasound were captured of the operative hip with the hip in 6 consistent positions: 3 views in hip extension (neutral [N], 30° internal rotation [IR], and 30° external rotation [ER]) and 3 views in hip flexion of 50° (neutral [F-N], 40° external rotation [F-ER40], and 60° external rotation [F-ER60]). A curved-array ultrasound transducer probe was used with the transducer placed in line with the femoral neck to evaluate the proximal femoral morphology. An open femoral osteoplasty using an anterior approach was performed. Fluoroscopy and ultrasound were again used to capture images with the hip in the same 6 positions. Bland-Altman plots were used to determine whether fluoroscopic and ultrasound alpha angles agreed at each position. Independent t-tests were used to compare the alpha angles between the 2 modalities at each position, and paired t-tests were used to compare preoperative and postoperative alpha angles at each position. RESULTS: No significant differences between the alpha angle on fluoroscopy and ultrasound at all 6 positions were appreciated preosteoplasty. The mean preoperative alpha angle on ultrasound in each position was as follows: N (55.4° ± 5.9° vs 43.0° ± 2.1°), IR (55.1° ± 5.3° vs 43.9° ± 5.5°), ER (58.6° ± 5.6° vs 42.8° ± 3.0°), F-N (53.9° ± 5.5° vs 41.6° ± 3.3°), F-ER40 (55.5° ± 4.6° vs 41.5° ± 2.7°), and F-ER60 (57.9° ± 6.5° vs 41.2° ± 4.2°). The mean preoperative and postoperative alpha angle on fluoroscopy in each position were as follows: N (56.0 ± 12.8° vs 43.1 ± 2.1°), IR (54.1 ± 13.4° vs 41.9 ± 2.9°), ER (61.2 ± 11.0° vs 44.2 ± 1.9°), F-N (57.9 ± 10.6° vs 44.0 ± 2.3°), F-ER40 (59 ± 8.2° vs 42 ± 2.2°), and F-ER60 (55 ± 7.6° vs 41.1 ± 2.6°). Postosteoplasty, there was no significant difference between the mean alpha angle on fluoroscopy versus ultrasound in any position except F-N (44.0 ± 2.3 vs 41.6 ± 3.3, P = .015). Bland-Altman plots showed a high level of agreement between alpha angle values on fluoroscopy and ultrasound at all positions pre- and postosteoplasty. There was a significant reduction in alpha angle measured on ultrasound and fluoroscopy at each position following osteoplasty. There were no significant differences in the delta of the pre- and postosteoplasty alpha angle measurements between fluoroscopy and ultrasound. CONCLUSIONS: Ultrasound is a useful tool for assessing a cam deformity in patients with femoroacetabular impingement syndrome and for determining adequate resection of a cam deformity intraoperatively. CLINICAL RELEVANCE: Due to the inherent limitations and risks of the fluoroscopy, it is worth evaluating other nonionizing imaging modalities. Ultrasound has potential to be an accessible, cost-effective, and safe imaging modality that lacks radiation and is commonly used for intra-articular hip injections and dynamic examination of the hip.

Machine Learning Algorithms Predict Achievement of Clinically Significant Outcomes After Orthopaedic Surgery: A Systematic Review.

PURPOSE: To determine what subspecialties have applied machine learning (ML) to predict clinically significant outcomes (CSOs) within orthopaedic surgery and to determine whether the performance of these models was acceptable through assessing discrimination and other ML metrics where reported. METHODS: The PubMed, EMBASE, and Cochrane Central Register of Controlled Trials databases were queried for articles that used ML to predict achievement of the minimal clinically important difference (MCID), patient acceptable symptomatic state (PASS), or substantial clinical benefit (SCB) after orthopaedic surgical procedures. Data pertaining to demographic characteristics, subspecialty, specific ML algorithms, and algorithm performance were analyzed. RESULTS: Eighteen articles met the inclusion criteria. Seventeen studies developed novel algorithms, whereas one study externally validated an established algorithm. All studies used ML to predict MCID achievement, whereas 3 (16.7%) predicted SCB achievement and none predicted PASS achievement. Of the studies, 7 (38.9%) concerned outcomes after spine surgery; 6 (33.3%), after sports medicine surgery; 3 (16.7%), after total joint arthroplasty (TJA); and 2 (11.1%), after shoulder arthroplasty. No studies were found regarding trauma, hand, elbow, pediatric, or foot and ankle surgery. In spine surgery, concordance statistics (C-statistics) ranged from 0.65 to 0.92; in hip arthroscopy, 0.51 to 0.94; in TJA, 0.63 to 0.89; and in shoulder arthroplasty, 0.70 to 0.95. Most studies reported C-statistics at the upper end of these ranges, although populations were heterogeneous. CONCLUSIONS: Currently available ML algorithms can discriminate the propensity to achieve CSOs using the MCID after spine, TJA, sports medicine, and shoulder surgery with a fair to good performance as evidenced by C-statistics ranging from 0.6 to 0.95 in most analyses. Less evidence is available on the ability of ML to predict achievement of SCB, and no evidence is available for achievement of the PASS. Such algorithms may augment shared decision-making practices and allow clinicians to provide more appropriate patient expectations using individualized risk assessments. However, these studies remain limited by variable reporting of performance metrics, CSO quantification methods, and adherence to predictive modeling guidelines, as well as limited external validation. LEVEL OF EVIDENCE: Level III, systematic review of Level III studies.

Patients Follow 3 Different Rate-of-Recovery Patterns After Anterior Cruciate Ligament Reconstruction Based on International Knee Documentation Committee Score.

PURPOSE: To determine whether subgroups of patients exist based on the rate-of-recovery pattern of International Knee Documentation Committee (IKDC) scores after anterior cruciate ligament reconstruction (ACLR) and to determine clinical predictors for these subgroups. METHODS: Patients who underwent primary or revision ACLR at a single institution from January 2014 to January 2019 were identified. Latent class growth analyses and growth mixture models (GMMs) with 1 to 6 classes were used to identify subgroups of patients based on functional rate-of-recovery patterns by use of preoperative, 1-year postoperative, and 2-year postoperative IKDC scores. RESULTS: A total of 245 patients who underwent ACLR were included in the analysis. A 3-class GMM was chosen as the final model after 6 different models were run. Class 1, showing improvement from preoperatively to 1-year follow-up, with sustained improvement from 1 to 2 years postoperatively, constituted 77.1% of the study population (n = 189), whereas class 2, showing functional improvement between 1- and 2-year follow-up, was the smallest class, constituting 10.2% of the study population (n = 25), and class 3, showing slight improvement at 1-year follow-up, with a subsequent decline in IKDC scores between 1- and 2-year follow-up, constituted 12.7% of the study population (n = 31). Revision surgery (P = .005), a psychiatric history (P = .025), preoperative chronic knee pain (P = .024), and a subsequent knee injury within the follow-up period (P = .011) were the predictors of class 2 and class 3 rate-of-recovery patterns. Patient demographic characteristics, graft type, and concomitant ligament, meniscus, or cartilage injury at the time of surgery were not associated with the different recovery patterns described in this study. CONCLUSIONS: Patients may follow different rate-of-recovery patterns after ACLR. By use of the GMMs, 3 different rate-of-recovery patterns based on IKDC scores were identified. Although most patients follow a more ideal rate-of-recovery pattern, fewer patients may follow less favorable patterns. Revision surgery, a history of psychiatric illness, preoperative chronic knee pain, and a subsequent knee injury within the follow-up period were predictive of less favorable rate-of-recovery patterns. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Complete Capsular Closure Provides Higher Rates of Clinically Significant Outcome Improvement and Higher Survivorship Versus Partial Closure After Hip Arthroscopy at Minimum 5-Year Follow-Up.

PURPOSE: To (1) compare the rates of reaching threshold hip-specific outcome scores for achieving the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) in patients who underwent partial versus complete T-capsulotomy repair and (2) identify the failure rates in each group 5 years after undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS). METHODS: Data from consecutive patients who underwent hip arthroscopy for FAIS performed by a single fellowship-trained surgeon from January 2011 to March 2013 were collected and analyzed. Baseline data, hip-specific outcomes, and clinical failure rates were recorded at a minimum of 5 years postoperatively. Patients with partial T-capsulotomy repair were matched 1:3 by age, body mass index, and sex to patients with complete T-capsulotomy repair. Threshold scores for achieving the MCID and PASS were calculated and compared between the 2 groups. Additionally, rates of revision and conversion to total hip arthroplasty (THA) were compared between the groups. RESULTS: A total of 379 patients were available for analysis (39 partial and 340 complete repairs), with 100 patients included in the matching process (25 in the partial-repair group and 75 in the complete-repair group). Comparison of radiographic parameters, including the Tönnis grade, alpha angle, and lateral center-edge angle, between the 2 groups showed no statistically significant difference (P > .05 for all). Comparison of postoperative score averages between the partial- and complete-closure groups showed a significant difference in the Hip Outcome Score-Activities of Daily Living Subscale (85.4 ± 17.7 vs 94.6 ± 7.8, P < .001), Hip Outcome Score-Sports Subscale (76.6 ± 26.2 vs 89.3 ± 16.8, P = .034), modified Harris Hip Score (83.2 ± 19.7 vs 90.5 ± 11.2, P = .035), and visual analog scale pain score (24.5 ± 30.8 vs 13.4 ± 15.8, P = .035). A total of 65 complete-repair patients (95.6%) achieved the MCID for at least 1 outcome measure versus 18 patients with partial repair (78.3%) (P = .04). A total of 69 complete-repair patients (92%) achieved the PASS for at least 1 outcome measure versus 18 partial-repair patients (72%) (P = .017). Of the 39 partial-repair patients, 35.9% (n = 14) underwent revision or conversion to THA, as compared with 2.9% (n = 10) in the overall cohort. CONCLUSIONS: At a minimum 5-year follow-up, patients with complete capsular closure after hip arthroscopy for FAIS show superior long-term outcomes and achieve higher rates of meaningful clinical success when compared with patients with partial capsular closure. Furthermore, patients with partial capsular repair undergo revision or conversion to THA at high rates. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Repeat Revision Hip Arthroscopy Outcomes Match That of Initial Revision But Not That of Primary Surgery for Femoroacetabular Impingement Syndrome.

PURPOSE: To (1) report on pre- and postoperative patient-reported outcome (PRO) scores for patients undergoing repeat revision surgery in short-term follow-up and (2) compare minimal clinically important difference (MCID) and patient acceptable symptomatic state achievement between primary, revision, and repeat revision hip arthroscopy cohorts. METHODS: Data from consecutive patients undergoing revision hip arthroscopy from January 2012 to February 2019 were retrospectively reviewed. Hips that underwent 2 revision hip arthroscopic surgeries were identified and matched 1:3 to patients undergoing revision surgery and 1:3 to patients undergoing primary surgery by age, sex, and body mass index. Baseline demographic data, surgical indications, and hip-specific PROs were collected were obtained preoperatively and at minimum 1-year follow-up. MCID was calculated individually for each cohort. RESULTS: Twenty patients who underwent repeat revision were matched to 60 patients who underwent revision and 60 primary patients. Patients who underwent repeat revision achieved MCID on all investigated PROs at a similar rate to patients undergoing primary surgery (90.0% vs 91.7%, P = .588) and at a greater rate than patients undergoing first-time revision surgery (90.0% vs 71.7%, P = .045). Patients who underwent repeat revision achieved patient acceptable symptomatic state on all investigated PROs at a similar rate to patients who underwent first-time revision (30.0% vs 55.0%, P = .053) but at a significantly lower rate than primary patients (30.0% vs 76.7%, P < .001). However, patients undergoing repeat revision surgery had significantly lower preoperative PROs (P < .001 for all) and no significant difference in PROs at minimum 1-year follow-up compared with patients undergoing revision (P > .05). Compared with the primary cohort, patients who underwent repeat revision had significantly lower Hip Outcome Score-Activities of Daily Living (77.3 ± 16.7 vs 86.1 ± 14.4; P = .034), Hip Outcome Score-Sports Subscale (60.6 ± 27.2 vs 76.1 ± 23.8; P < .001), and modified Harris Hip Score (69.2 ± 19.3 vs 81.7 ± 16.1; P = .048) at a minimum of 1-year follow-up. CONCLUSIONS: Second-time revision hip arthroscopy, which often requires advanced procedures, results in clinically significant improvement in PROs; however, outcomes for repeat revision cases are similar to first-time revision cases but inferior to those obtained following primary surgeries. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Assessment of Association Between Spino-Pelvic Parameters and Outcomes Following Gluteus Medius Repair.

PURPOSE: To evaluate postoperative coronal/sagittal spinal plane and spinopelvic parameters in patients undergoing gluteus medius repair and to identify associations between outcomes and the aforementioned spinopelvic variables. METHODS: Patients who underwent gluteus medius/minimus repair by a single surgeon between January 20, 2012, and November 25, 2015, were retrospectively identified from a prospectively collected database. Radiographic measurements included Cobb angle, lumbar lordosis, sagittal vertical axis (SVA), pelvic tilt, sacral slope, and pelvic incidence. Patient-reported outcomes (PROs) were obtained at baseline and a minimum of 22 months after surgery. Bivariate correlation determined effects of spinopelvic measurements on PROs. Scoliosis and nonscoliosis groups were compared using independent samples t-test, and multivariate analysis determined whether the preoperative variables affected outcomes. RESULTS: Thirty-eight (80.9%) of 47 consecutive patients were radiographically evaluated with a scoliosis series. All patients demonstrated significant improvements in all PROs and pain (P < .001 for all), as well as at an average 28.2 ± 7.8 (range, 22-51) months after surgery. There were significant negative relationships between SVA and Hip Outcome Score-Activities of Daily Living (r = -0.405, P = .026) and Hip Outcome Score-Sports Specific (r = -0.492, P = .011) scores. Patients with a positive SVA (>0 cm) had significantly worse patient-reported outcomes than their counterparts with negative (≤0 cm) SVA. Also, patients with positive sagittal plane deformity (SVA >5 cm) had significantly worse HOS-SS than patients without positive sagittal plane deformity (SVA <5 cm) (47.0 ± 35.3, 73.2 ± 24.0; P = .04). Independent sample t-testing for the patients with scoliosis (n = 18) versus no scoliosis (n = 20) demonstrates a significantly worse postoperative International Hip Outcome Tool (short version) score in the patients with scoliosis (77.4 ± 15.1, 53.8 ± 37.1; P = .043). CONCLUSIONS: Patients with scoliosis presented with lower rates of symptom improvement and ability to return to an active lifestyle in patients with hip disorders. In addition, patients with positive sagittal plane deformity experienced lower hip-related sport-specific outcome scores. Although the direct relationship between the spine and the hip in patients after gluteus medius/minimus repair remains unclear, this study shows an association between these postoperative outcomes and spinopelvic parameters. LEVEL OF EVIDENCE: Level IV, case series.

Intra-articular Volume Reduction With Arthroscopic Plication for Capsular Laxity of the Hip: A Cadaveric Comparison of Two Surgical Techniques.

PURPOSE: To compare intracapsular volume reduction between interportal capsular shift and T-capsulotomy plication in a cadaveric model. METHODS: Twelve pair-matched specimens were randomized into T-capsulotomy plication or interportal capsular shift. T-capsulotomy was performed using a 2-cm interportal and 2-cm bisecting, longitudinal limb to the intertrochanteric line. Plication was performed utilizing 5-mm bites on either side of the capsulotomy with arthroscopic knot tying technique standard alternating half hitches. Pair-matched interportal capsular shift specimens underwent 5-cm interportal capsulotomy, and capsular shift was performed utilizing 5 nonabsorbable sutures placed in 45° orientation at 5 mm from the capsulotomy margin. With each specimen in a position of slight flexion and adduction, a spinal needle was used to inject methylene blue-colored saline solution intra-articularly; the volcano method was used to measure capsular volume before and after each respective plication technique. Mean absolute volumes and relative volumetric reduction for each technique were quantified and compared to determine statistical significance. RESULTS: At baseline, there were no statistically significant differences in capsular volume between pair-matched specimens (T-capsulotomy plication, 42.5 ± 5.1 mL; interportal capsular shift, 45.0 ± 88.6 mL; P = .555). After capsulotomy and secondary plication, both the T-capsulotomy (post: mean = 32.5 ± 8.0 mL; P < .001) and interportal capsulotomy groups (post: mean = 29.4 ± 10.0; P < .0001) demonstrated significant decreases in capsular volume, with average reductions of 10.0 ± 3.3 mL and 15.6 ± 3.2 mL, respectively. Although the interportal capsular shift (35.9% ± 11.3%) demonstrated greater volumetric reduction relative to baseline when compared with the T-capsular plication (24.5% ± 10.8%), these results were not significant (P = .104). CONCLUSIONS: Both T-capsular plication and interportal capsular shift produce statistically significant reductions in overall hip capsular volume. Although the interportal capsular shift may generate modestly higher degrees of capsular reduction, the comparative biomechanical repercussions of each technique are not currently known. CLINICAL RELEVANCE: Irrespective of arthroscopic technique, capsular plication with 5-mm bites decreases capsular volume by approximately one-third to one-fourth that of baseline measures.

The Influence of Pain in Other Major Joints and the Spine on 2-Year Outcomes After Hip Arthroscopy.

PURPOSE: To determine whether patients who have pain in other major joints or the spine have poorer postsurgical outcomes than patients without comorbid orthopaedic pain. METHODS: We performed a review of a prospectively maintained institutional surgical registry of patients who underwent hip arthroscopy between January 1, 2012, and July 16, 2015, by a single surgeon, with a minimum of 2 years of postoperative follow-up. A musculoskeletal morbidity (MSM) score was assigned to each patient preoperatively based on the presence of pain in other joints and the spine (grade 1, hip only; grade 2, hip and other major joints without spine; grade 3, hip with spine; and grade 4, hip and other major joints with spine). Preoperatively and at 2 years postoperatively, functional outcomes were measured using the Hip Outcome Score-Activities of Daily Living (HOS-ADL), and the percentages of patients achieving a minimal clinically important difference (MCID) and patient-acceptable symptom state (PASS) were calculated. RESULTS: In total, 821 patients were identified, of whom 700 (85.3%) completed 2-year follow-up. Preoperatively, MSM grade 1 patients had a higher HOS-ADL than grade 2 patients (P = .02), but there was no difference between grade 1 and grade 3 patients (P = .63) or between grade 1 and grade 4 patients (P = .14). Likewise, there was no difference in the preoperative HOS-ADL among grades 2, 3, and 4. Patients with MSM grades 1 and 2 were younger than those with grades 3 and 4. At 2 years postoperatively, MSM grade 1 patients had higher HOS-ADL values than grade 3 (P = .01) and grade 4 (P = .02) but not grade 2 (P = .07) patients. Overall, 84% of patients showed an MCID and 72% of patients achieved a PASS with regard to the HOS-ADL. There were no statistically significant differences among MSM grades in terms of the MCID or PASS. CONCLUSIONS: Overall, 84% of patients improved with hip arthroscopy by MCID criteria for the HOS-ADL. Patients with no pain in other joints (MSM grade 1) had better 2-year postoperative HOS-ADL values after hip arthroscopy than patients with spine pain (grades 3 and 4). However, there were no significant differences in the MCID or PASS among patients with regard to MSM grade. A total of 40.5% of patients who underwent hip arthroscopy had pain in another joint. A limitation, however, is that there is potential for a type II error, in that there may not have been a sufficient number of patients studied to detect a significant difference in outcome among patients with different grades of musculoskeletal comorbidity. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Indirect Head of the Rectus Femoris Tendon as a Graft for Segmental Hip Labral Reconstruction: An Anatomic, Radiographical, and Biomechanical Study in Comparison With Iliotibial Labral Reconstruction.

BACKGROUND: The indirect head of the rectus femoris (IHRF) tendon has been used as an autograft for segmental labral reconstruction. However, the biomechanical properties and anatomic characteristics of the IHRF, as they relate to surgical applications, have yet to be investigated. PURPOSE: To (1) quantitatively and qualitatively describe the anatomy of IHRF and its relationship with surrounding arthroscopically relevant landmarks; (2) detail radiographic findings pertinent to IHRF; (3) biomechanically assess segmental labral reconstruction with IHRF, including restoration of the suction seal and contact pressures in comparison with iliotibial band (ITB) reconstruction; and (4) assess potential donor-site morbidity caused by graft harvesting. STUDY DESIGN: Descriptive laboratory study. METHODS: A cadaveric study was performed using 8 fresh-frozen human cadaveric full pelvises and 7 hemipelvises. Three-dimensional anatomic measurements were collected using a 3-dimensional coordinate digitizer. Radiographic analysis was accomplished by securing radiopaque markers of different sizes to the evaluated anatomic structures of the assigned hip.Suction seal and contact pressure testing were performed over 3 trials on 6 pelvises under 4 different testing conditions for each specimen: intact, labral tear, segmental labral reconstruction with ITB, and segmental labral reconstruction with IHRF. After IHRF tendon harvest, each full pelvis had both the intact and contralateral hip tested under tension along its anatomic direction to assess potential site morbidity, such as tendon failure or bony avulsion. RESULTS: The centroid and posterior apex of the indirect rectus femoris attachment are respectively located 10.3 ± 2.6 mm and 21.0 ± 6.5 mm posteriorly, 2.5 ± 7.8 mm and 0.7 ± 8.0 mm superiorly, and 5.0 ± 2.8 mm and 22.2 ± 4.4 mm laterally to the 12:30 labral position. Radiographically, the mean distance of the IHRF to the following landmarks was determined as follows: anterior inferior iliac spine (8.8 ± 2.5 mm), direct head of the rectus femoris (8.0 ± 3.9 mm), 12-o'clock labral position (14.1 ± 2.8 mm), and 3-o'clock labral position (36.5 ± 4.4 mm). During suction seal testing, both the ITB and the IHRF reconstruction groups had significantly lower peak loads and lower energy to peak loads compared with both intact and tear groups (P = .01 to .02 for all comparisons). There were no significant differences between the reconstruction groups for peak loads, energy, and displacement at peak load. In 60° of flexion, there were no differences in normalized contact pressure and contact area between ITB or IHRF reconstruction groups (P > .99). There were no significant differences between intact and harvested specimen groups in donor-site morbidity testing. CONCLUSION: The IHRF tendon is within close anatomic proximity to arthroscopic acetabular landmarks. In the cadaveric model, harvesting of the IHRF tendon as an autograft does not lead to significant donor-site morbidity in the remaining tendon. Segmental labral reconstruction performed with the IHRF tendon exhibits similar biomechanical outcomes compared with that performed with ITB. CLINICAL RELEVANCE: This study demonstrates the viability of segmental labral reconstruction with an IHRF tendon and provides a detailed anatomic description of the tendon in the context of an arthroscopic labral reconstruction. Clinicians can use this information during the selection of a graft and as a guide during an arthroscopic graft harvest.

Spinopelvic Parameters Do Not Influence Outcomes Following Primary Hip Arthroscopy for the Treatment of Femoroacetabular Impingement Syndrome.

Purpose: To evaluate the influence of spinopelvic parameters on short-term postoperative patient-reported outcomes (PROs) following primary hip arthroscopy for the treatment of femoroacetabular impingement syndrome (FAIS). Methods: Patients undergoing primary hip arthroscopy between January 2012 and December 2015 were retrospectively reviewed. Hip Outcome Score - Activities of Daily Living, Hip Outcome Score - Sports-Specific Subscale, modified Harris Hip Score, International Hip Outcome Tool-12, and visual analog scale pain were recorded preoperatively and at final follow-up. Lumbar lordosis (LL), pelvic tilt (PT), sacral slope, and pelvic incidence (PI) were measured on lateral radiographs in standing position. Patients were split into subgroups for individual analyses based on previous literature cutoffs: |PI-LL|> or <10°, PT> or <20°, and PI <40°, 40° < PI < 65°, and PI >65°. PROs and rate of achievement of patient acceptable symptom state (PASS) were compared between subgroups at final follow-up. Results: Sixty-one patients who underwent unilateral hip arthroscopy were included in the analysis, and 66% of patients were female. Mean patient age was 37.6 ± 11.3 years, whereas mean body mass index was 25.0 ± 5.7. Mean follow-up time was 27.6 ± 9.0 months. No significant difference in preoperative nor postoperative PROs were appreciated in patients with spinopelvic mismatch (|PI-LL| >10°) versus those without, whereas patients with mismatch achieved PASS according to the modified Harris Hip Score (P = .037) and International Hip Outcome Tool-12 (P = .030) at greater rates. When we compared patients with a PT ≥20° versus PT <20°, no significant differences in postoperative PROs were present. When we compared patients in the following pelvic incidence groups: PI <40°, 40° < PI <65°, and PI >65°, no significant differences in 2-year PROs or rates of PASS achievement for any PRO were appreciated (P > .05 for all). Conclusions: In this study, spinopelvic parameters and traditional measures of sagittal imbalance did not influence PROs in patients undergoing primary hip arthroscopy for FAIS. Patients with sagittal imbalance (|PI-LL|> 10° or PT >20°) achieved a greater rate of PASS. Level of Evidence: IV; Prognostic case series.

Determining the Roles of the Anterior Cruciate Ligament, Posterolateral Corner, and Medial Collateral Ligament in Knee Hyperextension Using the Heel-Height Test.

Background: Anterior cruciate ligament (ACL) tears are often associated with other ligamentous injuries. The side-to-side difference in heel height can represent a valuable diagnostic tool in the setting of multiligamentous injuries. Purpose: To assess in a cadaveric model how sequential sectioning of the static stabilizing structures of the knee (ACL, fibular collateral ligament [FCL], popliteus tendon [PLT], popliteofibular ligament [PFL], and medial collateral ligament [MCL]) influences heel-height measurements when comparing groups undergoing initial transection of the ACL versus FCL and to assess posterior tibial slope after sequential sectioning. Study Design: Controlled laboratory study. Methods: A total of 16 fresh cadaveric knees were carefully dissected to expose the ACL, FCL, PLT, PFL, and MCL. Each knee was randomized to either the ACL-first or FCL-first group based on the initial structure sectioned. The sectioning order was as follows: (1) ACL or FCL, (2) FCL or ACL, (3) PLT, (4) PFL, and (5) MCL. Heel height was measured with a standardized superiorly directed 12-N·m force applied to the knee while stabilizing the femur; heel height was also measured with a clinician-applied force. The measurements were compared between and within groups for each sectioned state. The correlation between tibial slope and heel-height measurements was analyzed. Results: There were no significant differences in heel-height measurements between the ACL-first and FCL-first groups (P = .863). Combined ACL-FCL injuries led to a 2.85 ± 0.83-cm increase in heel height compared to the intact state. Significant increases in heel height occurred after all sectioned states, except the PFL sectioned state. Combined ACL-posterolateral corner (PLC) injuries resulted in a 3.72 ± 1.02-cm increase in heel height, and additional sectioning of the MCL resulted in a 4.73 ± 1.35-cm increase compared to the intact state. Tibial slope was not correlated with increases in heel height after each sectioning (P = .154). Conclusion: Combined ACL-FCL, ACL-PLC, and ACL-PLC-MCL injuries resulted in increasing mean heel-height measurements (2.85, 3.72, and 4.73 cm, respectively) compared to the intact state. Tibial slope was not found to influence increases in heel height. Clinical Relevance: The side-to-side difference in heel height may be a clinically relevant examination tool for diagnosing multiligament knee injuries.

Ultrasound Can Determine Joint Distraction During Hip Arthroscopy but Fluoroscopic-Guided Portal Placement Is Superior.

Purpose: To compare joint distraction measured on ultrasound (US) with joint space width (JSW) measured on fluoroscopy in hip arthroscopy and to determine whether ultrasound guidance is as safe and effective as fluoroscopy, the current gold standard, for establishing arthroscopic portals. Methods: Cadaveric whole-body specimens were positioned supine and subjected to 60 lbs. of unilateral axial traction using a distal femoral Steinman pin. Joint distraction was measured via JSW on fluoroscopic and ultrasound images. A single, fellowship-trained orthopaedic surgeon established anterolateral arthroscopy portals via ultrasound or fluoroscopic guidance in a randomized sequence. Total procedure time, number of times the spinal needle pierced the capsule, and iatrogenic chondral or labral injury were recorded. Results: Twelve full-body specimens (20 hips) underwent distraction, and 17 hips underwent portal placement with fluoroscopic (n = 8) or ultrasound (n = 9) guidance. JSW measured on ultrasound was significantly less laterally (13.0 vs 9.2 mm, P < .001), apically (16.7 vs 9.2 mm, P < .001), and medially (17.9 vs 9.2 mm, P < .001). Successful portal entry was achieved in every specimen. Average procedure time was 133 ± 51 seconds for the fluoroscopy group and 371 ± 260 seconds for the ultrasound group (P = .026). Fluoroscopic guidance required significantly less needle insertion attempts at 1.13 compared with 3.33 attempts for ultrasound (P = .022). Labral damage was greater in the ultrasound group at 66.67% compared with 12.50% for fluoroscopy (P = .0497). Conclusions: Joint distraction measured on ultrasound can be used to subjectively determine if the joint is adequately distracted in hip arthroscopy. Ultrasound-guided portal placement was associated with more needle insertion attempts, iatrogenic injury of the labrum, and overall procedure time in comparison to fluoroscopic guidance. Clinical Relevance: Fluoroscopy is the gold standard to confirm adequate joint distraction, aid in establishing arthroscopy portals, and evaluate resection of the femoral head during hip arthroscopy but exposes the patient to ionizing radiation, requires additional operators in the operating room, and involves the need for a heavy lead shield. Alternatives to fluoroscopy are needed, but ultrasound has not proven superior in our cadaveric model.

Return to Sport in Athletes With Borderline Hip Dysplasia After Hip Arthroscopy for Femoroacetabular Impingement Syndrome.

BACKGROUND: Data on outcomes in patients with borderline hip dysplasia (BHD) who undergo hip arthroscopy remain limited, particularly in regard to return to sport (RTS). PURPOSE: To evaluate outcomes in patients with BHD and their ability to RTS after hip arthroscopy for treatment of femoroacetabular impingement syndrome (FAIS). STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Consecutive patients with self-reported athletic activity and radiographic evidence of BHD, characterized by a lateral femoral center-edge angle (LCEA) between 18° and 25° and a Tönnis angle >10°, who underwent hip arthroscopy for FAIS between November 2014 and March 2017 were identified. Patient characteristics and clinical outcomes including the Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), international Hip Outcome Tool (iHOT-12), and visual analog scale (VAS) for pain and satisfaction were analyzed at minimum 2-year follow-up. In addition, all patients completed an RTS survey. RESULTS: A total of 41 patients with a mean age and body mass index (BMI) of 29.6 ± 13.4 years and 25.3 ± 5.6, respectively, were included. Mean LCEA and Tönnis angle for the study population were 22.7°± 1.8° and 13.3°± 2.9°, respectively. A total of 31 (75.6%) patients were able to RTS after hip arthroscopy at a mean of 8.3 ± 3.2 months. A total of 14 patients (45.2%) were able to RTS at the same level of activity, 16 patients (51.6%) returned to a lower level of activity, and only 1 (3.2%) patient returned to a higher level of activity. Of the 11 high school and collegiate athletes, 10 (90.9%) were able to RTS. All patients demonstrated significant improvements in all patient-reported outcome measures (PROMs) as well as in pain scores at a mean of 26.1 ± 5.4 months after surgery. Patients who were able to RTS had a lower preoperative BMI than patients who did not RTS. Analysis of minimum 2-year PROMs demonstrated better HOS-ADL, HOS-SS, mHHS, iHOT-12, and VAS outcomes for pain in patients able to RTS versus those who did not RTS (P < .05). CONCLUSION: Of the patients with BHD studied here, 75.6% of patients successfully returned to sport at a mean of 8.3 ± 3.2 months after hip arthroscopy for FAIS. Of the patients who successfully returned to sport, 45.2% returned at the same level, and 3.2% returned at a higher activity level.

Biomechanical Role of the Superior Capsule in a Rotator Cuff Sectioned and Repaired State: A Sequential Sectioning Study.

BACKGROUND: Individual contributions of the rotator cuff (RC) and superior capsule (SC) to prevent superior translation of the humerus are not well understood. PURPOSE: To evaluate the relative contributions of the SC and RC to normal and pathologic shoulder biomechanics by determining their independent effects on superior humeral translation. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve cadaveric shoulders were tested at 0º, 45º, and 90º of abduction under 5 conditions: intact RC/SC, RC sectioned first, SC sectioned first, both structures sectioned, and RC repair. Matched pairs were randomly assigned to the second or third testing condition (RC or SC sectioned first). Specimens were tested under 2 static conditions (40-N deltoid load [balanced load], 80-N deltoid load [superiorly directed load]) and 1 dynamic condition during active abduction. A mixed-design 2-way repeated-measures analysis of variance with Bonferroni adjustments was performed to compare testing conditions. Paired t tests were used to compare specimens in the intact state versus the repaired state. Significance was set at P < .05. RESULTS: During balanced deltoid loading at 0° and 45º, there was significantly greater humeral translation when both structures were sectioned as compared with the intact state and with both isolated sectioned states (P < .05 for all). No significant differences were observed between or within groups at 90º of abduction. These effects remained consistent with superiorly directed loading. Dynamic testing of both groups showed a significant increase in superior translation for specimens in which the RC was deficient versus the intact state (P = .027), with no difference when the SC was sectioned. The RC repair state returned translation to values similar to the intact state at all abduction angles and loading conditions (P > .05). CONCLUSION: In this cadaveric study, the SC and RC played an important role in preventing superior humeral translation; however, dynamic testing suggested preferential contribution of the RC. RC repair was effective in preventing superior humeral translation, even with a sectioned SC at the level of the glenohumeral joint. CLINICAL RELEVANCE: RC repair was effective in preventing superior humeral translation, even in the presence of a sectioned SC at the level of the glenohumeral joint in this cadaveric model. Our data lay the groundwork for future studies investigating the clinical effect of RC repair in an SC sectioned state.

Use of Younger Patient Age and Greater Anterior Center-Edge Angle to Predict the Need for Bilateral Hip Arthroscopy in Patients With Bilateral Femoroacetabular Impingement-Related Hip Pain.

BACKGROUND: In patients with symptomatic femoroacetabular impingement syndrome, bilateral hip pain has been reported to occur in high frequency. However, not all patients require bilateral hip arthroscopy. PURPOSE: To determine the incidence, patient-specific variables, and postoperative outcomes in patients who presented with bilateral hip pain at the time of index hip arthroscopy and underwent subsequent contralateral arthroscopic hip surgery. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients who presented with bilateral hip pain, underwent primary hip arthroscopy between January 2012 and June 2018 for indication of femoroacetabular impingement syndrome, and had minimum 2-year follow-up were retrospectively analyzed. Baseline descriptive data, preoperative hip range of motion, and radiographic measurements were recorded with pre- and postoperative patient-reported outcomes (PROs). Independent samples t test was used to compare continuous variables, and chi-square test was used to compare categorical variables between patients undergoing unilateral and bilateral surgery. Bivariate correlations and a multivariable binary logistic regression were performed to determine factors predictive of the need for future contralateral hip arthroscopy. RESULTS: In total, 108 patients were identified who reported bilateral hip pain during the index evaluation, underwent primary hip arthroscopy, and had 2-year follow-up. Among these, 42% (n = 45) elected to undergo hip arthroscopy on the contralateral hip at a mean of 6.0 months (range, 1-17 months) after the index surgery. Patients requiring bilateral surgery were significantly younger (P = .004) and had a larger preoperative anterior center-edge angle (ACEA; P = .038) when compared with patients who had unilateral surgery. There were no significant differences in alpha angle measurements between patients who had unilateral and bilateral surgery. On bivariate analysis, younger age at the time of the index surgery (r = -0.272; P = .005) and preoperative ACEA (r = 0.249; P = .016) were significantly correlated with the need for bilateral surgery. On multivariate analysis, younger age remained a significant predictor for bilateral surgery (odds ratio, 0.95; 95% CI, 0.91-0.99). Patients who underwent bilateral hip arthroscopy reported significant improvement in all PROs (P < .001), with a significantly greater mean Hip Outcome Score- Sports Specific Subscale score when compared with patients undergoing unilateral surgery (P = .037). CONCLUSION: Subsequent contralateral hip arthroscopy was performed in 42% of patients who presented with bilateral hip pain. Younger age at the time of the index surgery and greater ACEA were predictive of the need for contralateral surgery. Patients undergoing bilateral surgery reported significantly improvement in PROs at minimum 2-year follow-up.

Patients Require Less Time to Complete Preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) Than Legacy Patient-Reported Outcome Measures.

PURPOSE: To analyze time to completion of preoperative legacy patient-reported outcomes (PROs) and more recent computer adaptive Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaires in patients with symptomatic femoroacetabular impingement syndrome undergoing primary hip arthroscopy. METHODS: A retrospective analysis was conducted on patients undergoing hip arthroscopy by a single fellowship-trained hip arthroscopist. Inclusion criteria were patients undergoing primary arthroscopic hip surgery and completion of at least 1 legacy PRO or PROMIS questionnaire at the preoperative time point. Exclusion criteria were history of contralateral or ipsilateral hip surgery, non-English-speaking patients, patients who completed PROs by phone or by paper form, and patients who did not complete preoperative PROs. Legacy PROs included modified Harris Hip Score (mHHS), Hip Outcome Score (HOS), International Hip Outcome Tool (iHOT-12), and Hip Pain Visual Analog Scale (VAS-Pain). PROMIS PROs included Physical Function (PROMIS-PF), Pain Interference (PROMIS-PI), and Depression (PROMIS-D). Only preoperative PROs were included in the analysis. Completion time was calculated using the questionnaire start and stop time reported by the survey collecting software. The median and interquartile range of each PRO were reported for analysis of central tendency and statistical dispersion, respectively. RESULTS: A total of 1,901 patients and 269 patients were included in the legacy and PROMIS groups, respectively. The median time required for completion of each PRO in (minutes: seconds) format was as follows: mHHS (1:29), HOS (3:58), iHOT (2:11), VAS-Pain (0:32), PROMIS-PF (0:46), PROMIS-PI (0:37), and PROMIS-D (0:43). The interquartile range of the middle 50% of respondents was as follows; mHHS (0:58), HOS (2:46), iHOT (1:22), VAS-Pain (0:28), PROMIS-PI (0:19), PROMIS-D (0:29), and PROMIS-PF (0:20). CONCLUSIONS: This study supports that preoperative PROMIS forms require less time to complete than preoperative legacy PROs and are not significantly influenced by age, race, or workers compensation status. LEVEL OF EVIDENCE: Level IV, case series.

Pain Catastrophizing and Kinesiophobia Affect Return to Sport in Patients Undergoing Hip Arthroscopy for the Treatment of Femoroacetabular Impingement.

PURPOSE: To assess whether pain catastrophizing and kinesiophobia affect return to sport (RTS) or clinically significant outcome (CSO) achievement in patients undergoing hip arthroscopy for the treatment of femoroacetabular impingement (FAI). METHODS: Patients undergoing primary hip arthroscopy at a single institution between January 2017 and March 2017 were prospectively enrolled. Patients received the Tampa Scale of Kinesiophobia-11 (TSK-11) and Pain Catastrophizing Scale (PCS) questionnaires preoperatively, 3 weeks, 6 weeks, 3 months, 6 months, and 1 year postoperatively. Patients also received the Hip Outcome Score Sport-Specific (HOS-SS) questionnaire preoperatively and 1 year and 2 years' postoperatively. An RTS questionnaire was completed at final follow-up. Bivariate correlations were conducted between PCS and TSK-11 scores and RTS status and achievement of CSOs of HOS-SS, based on patient acceptable symptom state (PASS) and substantial clinical benefit (SCB). RESULTS: Fifty-eight patients with an average age of 31.9 ± 12.2 and body mass index of 24.0 ± 3.8 participated in sport prior to surgery and were included in the study. Forty-two (72.4%) patients returned to sport at 10.5 ± 7.1 months following surgery. There was a significant reduction in TSK-11 and PCS scores at 1-year follow-up (TSK-11, 26.1 ± 6.0 vs 18.6 ± 6.1, P < .001; PCS, 17.7 ± 10.5 vs 4.3 ± 6.8, P < .001) as well as a significant improvement in HOS-SS (P < .001). At 1 year, fair correlations were demonstrated between PCS (r = -0.446, P = .010) and TSK (r = -0.330, P = .029) scores and RTS. Patient who returned to sport had lower PCS (8.5 ± 11.7 vs 3.0 ± 3.7, P = .010) and TSK-11 (21.8 ± 8.5 vs 17.6 ± 4.8, P = .029) scores at 1 year. At 1-year follow-up, PCS (r = -0.572, P = .001) and TSK-11 (r = -0.441, P = .012) scores demonstrated fair correlations with achieving PASS for HOS-SS at 2-year follow-up. CONCLUSIONS: Patient kinesiophobia and pain catastrophizing at 1-year follow-up were negatively correlated with RTS and achievement of a CSO in sport-related activities at 2-year follow-up. LEVEL OF EVIDENCE: III, prospective cohort study.

Hypermobile Disorders and Their Effects on the Hip Joint.

Hypermobility, or joint hyperlaxity, can result from inherited connective tissue disorders or from micro- or macrotrauma to a joint. The supraphysiologic motion of the hip joint results in capsuloligamentous damage, and these patients have a propensity to develop femoroacetabular impingement syndrome (FAIS) and labral injury. In this review, the recent literature evaluating the definitions, history, incidence, genetics, and histology of hypermobile disorders is investigated. We then review the clinical evaluation, natural history, and resulting instability for patients presenting with a hypermobile hip. Lastly, treatment options and outcomes will be highlighted.

High rate of return to tennis after hip arthroscopy for patients with femoroacetabular impingement syndrome.

OBJECTIVE: The purpose of this study was to evaluate return to sport (RTS) outcomes in tennis athletes following hip arthroscopy for femoroacetabular impingement syndrome (FAIS). It was hypothesized that there would be a high rate of return to tennis after hip arthroscopy. STUDY DESIGN: Level IV, Retrospective Analysis. SETTING: Outpatient sports medicine clinic at a single institution. PARTICIPANTS: A total of 28 patients (60.8% female; mean age, 36.2 ± 9.2 years; mean BMI, 22.8 ± 2.1 kg/m2) with self reported tennis activity prior to hip arthroscopy. MAIN OUTCOME MEASURES: A postoperative return to sport and minimum two-year patient reported outcomes. RESULTS: There was a high rate of return to tennis, with 78% of patients eventually returning to tennis. An additional 9% of patients had the necessary hip function to return, but did not return due to lack of interest or resources. The patients returned to tennis at an average of 8.0 ± 3.3 months after surgery. The majority of athletes (66.7%) were able to continue competing at the same or higher levels following surgery. CONCLUSIONS: Patients return to tennis 78% of the time at a mean of 8.0 ± 3.3 months following hip arthroscopy for FAIS.

Arthroscopic Treatment of Femoroacetabular Impingement Using Labral Reconstruction with Capsular Autograft.

The acetabular labrum is essential for stability during physiologic motion of the hip. Labral repairs frequently are attempted in cases of primary tears, although labral reconstruction is an important alternative in the revision setting or in the primary setting when the tissue is unsalvageable. Labral reconstruction has been shown to restore the hip's suction-seal and fluid pressurization to that of the premorbid state, and cohort studies have demonstrated significantly improved patient-reported outcomes at midterm follow-up. Notably, the cost is of consideration during any reconstruction, and techniques have been described using both allograft and autograft sources. Autograft sources include the iliotibial band, ligamentum teres, gracilis tendon, and hip capsule. A previously described technique using the capsule was noted to hinder routine capsular closure. We present an alternative method for labral reconstruction using hip capsular tissue that is easily performed and allows for routine capsular closure.