Faculty Bibliography

BACKGROUND:Three-dimensional MR fingerprinting (3D-MRF) has been increasingly used to assess cartilage degeneration, particularly in the knee joint, by looking into multiple relaxation parameters. A comparable 3D-MRF approach can be adapted to assess cartilage degeneration for the hip joint, with changes to accommodate specific challenges of hip joint imaging. PURPOSE/OBJECTIVE:in clinically feasible scan times. STUDY TYPE/METHODS:Prospective. SUBJECTS/METHODS:Eight healthy subjects, three patients with mild osteoarthritis (OA), and one of the OA patients had femoral acetabular impingement (FAI). A National Institute of Standards and Technology/International Society for Magnetic Resonance in Medicine (NIST/ISMRM) system phantom was also used. FIELD STRENGTH/SEQUENCE/UNASSIGNED:mapping. ASSESSMENT/RESULTS:maps of 3D-MRF sequence were evaluated on a NIST/ISMRM phantom and human subjects. Differences in the parametric maps between OA and healthy subjects were assessed. STATISTICAL TESTS/METHODS:Regression, Bland-Altman, Kruskal-Wallis, and Wilcoxon tests were used to assess for accuracy, repeatability, and subregional variation. The P-value <0.05 indicated statistically significant. RESULTS:) in femoral lateral compartment of the hip joint compared to healthy controls. DATA CONCLUSION/CONCLUSIONS:3D-MRF may be a feasible approach for simultaneous, quantitative mapping of bilateral hip joint cartilage in healthy and mild OA patients. EVIDENCE LEVEL/METHODS:1 TECHNICAL EFFICACY: Stage 1.

INTRODUCTION/BACKGROUND:Bone Marrow Lesions (BMLs) have a strong correlation to patient reported pain, functional limitations, joint deterioration, and rapid progression to total knee arthroplasty. The Subchondroplasty® (SCP) Procedure uses AccuFill®, a calcium phosphate bone substitute material (BSM), to treat bone defects such as microtrabecular fractures and BML. METHODS:This observational, prospective, multicenter, cohort study evaluated the effect of the SCP Procedure at two-year follow-up for 70 patients with knee BML. Under arthroscopic and fluoroscopic guidance, the BML was injected with AccuFill®. Patient reported outcomes, including Visual Analog Scale (VAS) pain, Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC), and modified Knee Society Score (mKSS) were collected through 24 months postoperatively. Radiographs and magnetic resonance images (MRI) were performed at baseline and up to 24 months post-operatively. Patient selection was not limited based on degree of osteoarthritis (OA) as determined radiologically by Kellgren-Lawrence (K-L) grade. For a subset of subjects, patient reported outcomes were collected up to five years including pain evaluation, patient knee global assessment, and satisfaction with the procedure. RESULTS:Pre-operative radiographs indicated moderate to severe osteoarthritis (K-L grades 2-4) in 65 subjects (92.8%). Significant improvements (p<0.0001) in mean VAS Pain, IKDC, mKSS and KOOS scores were observed compared with baseline. Kaplan-Meier survivorship free from conversion to knee arthroplasty was 76.2% at two years. The subset of subjects followed for five years demonstrated low pain scores and high procedure satisfaction. CONCLUSION/CONCLUSIONS:This study presents statistically significant and clinically meaningful evidence of improvement in clinical outcomes following SCP for BMLs of the knee after two years. The survivorship rate from arthroplasty at two years was 76.2%. SCP for BMLs can relieve pain with a minimally invasive procedure and may delay the need for knee arthroplasty.

Femoroacetabular impingement (FAI) is a cause of hip pain and can lead to hip osteoarthritis. Radiological measurements obtained from radiographs or magnetic resonance imaging (MRI) are normally used for FAI diagnosis, but they require time-consuming manual interaction, which limits accuracy and reproducibility. This study compares standard radiologic measurements against radiomics features automatically extracted from MRI for the identification of FAI patients versus healthy subjects. Three-dimensional Dixon MRI of the pelvis were retrospectively collected for 10 patients with confirmed FAI and acquired for 10 healthy subjects. The femur and acetabulum were segmented bilaterally and associated radiomics features were extracted from the four MRI contrasts of the Dixon sequence (water-only, fat-only, in-phase, and out-of-phase). A radiologist collected 21 radiological measurements typically used in FAI. The Gini importance was used to define 9 subsets with the most predictive radiomics features and one subset for the most diagnostically relevant radiological measurements. For each subset, 100 Random Forest machine learning models were trained with different data splits and fivefold cross-validation to classify healthy subjects versus FAI patients. The average performance among the 100 models was computed for each subset and compared against the performance of the radiological measurements. One model trained using the radiomics features datasets yielded 100% accuracy in the detection of FAI, whereas all other radiomics features exceeded 80% accuracy. Radiological measurements yielded 74% accuracy, consistent with previous work. The results of this preliminary work highlight for the first time the potential of radiomics for fully automated FAI diagnosis.

PURPOSE/OBJECTIVE:Proximal hamstring tears may present with neurological dysfunction due to compression or stretching of the sciatic nerve. The purpose of this study was to evaluate the effectiveness of hamstring repair with concurrent sciatic nerve neurolysis for clinical outcomes and patient symptoms. METHODS:A retrospective chart review of patients who were diagnosed with hamstring injury at a large tertiary care institution was conducted. Patients with chronic tears (> 6 weeks from injury to surgery) who underwent hamstring repair were reviewed for demographics, clinical variables including symptoms of sciatic neuritis, sciatic nerve abnormalities on MRI, and postoperative outcomes. Chi-square tests were used for categorical variables, t test for continuous variables. Pairwise t tests were used to compare average pre- and postoperative strength for patients with and without symptoms of sciatic neuritis. RESULTS:Thirty-two patients with chronic hamstring tears were included in the analysis. Patients were 59.4% female with an average age of 51.4 years (SD 13.1). Preoperatively, 27 patients (84.4%) were noted to have symptoms of sciatic neuritis. These patients did not differ in age (p = .677) or sex (p = .374) from patients without preoperative symptoms. Sciatic nerve abnormalities were noted on MRI report in 7 patients who had sciatic nerve symptoms and 0 patients who did not have sciatic nerve symptoms. Symptomatic improvement was seen in 21/26 (81%) of patients who had preoperative neurological symptoms, and in 6/7 (86%) of patients with MRI findings. All patients had equivalent or improved strength postoperatively. CONCLUSION/CONCLUSIONS:A sciatic nerve neurolysis is a safe and effective procedure to perform on patients with preoperative sciatic nerve symptoms and chronic hamstring tears that leads to improvement in neurological symptoms and strength. In neurologically asymptomatic patients with chronic hamstring injuries and MRI findings indicating possible nerve damage, a discussion should be held about the risks and benefits of performing a sciatic nerve neurolysis.

Compared with total hip arthroplasty, hip arthroscopy is a relatively new procedure and, as such, hip-spine syndrome in young adults is an emerging topic of research. In the past decade, our understanding of spinopelvic alignment has improved the stability and survivorship of hip replacements in patients with prior lumbar fusions. Obviously, the hip affects the spine and the spine affects the hip. In terms of hip arthroscopy, just as older patients and patients with cartilage damage have inferior outcome, patients with spine pathology are at risk for post-operative worsening spinal symptoms, including sciatica. In addition, back and radicular pain may limit post-operative hip rehabilitation. Yet, other patients show resolution of back symptoms after hip arthroscopy. Today, surgeons indicating hip arthroscopy must first investigate patient sagittal balance which includes pelvis tilt, pelvic incidence and sacral slope. When properly indicated, hip-spine pain patients show greater percentage improvement with no increased failure risk compared to patients with isolated FAIS. Exceptions include patients with concomitant lumbar stenosis or lumbar fusion. rate of revision hip arthroscopy and conversion for total hip replacement is two-fold compared to controls if patients had prior 1-2 level fusion and three-fold if 3 or more levels are fused. Our understanding of hip-spine patients with regard to arthroscopy outcomes continues to develop. In addition to a comprehensive spine exam, the patient's spine surgical history and current spine symptoms must be investigated in order to predit the efficacy of hip arthroscopy. If patients have both hip and spine symptoms, a diagnostic hip injection to determine the prime pain generator is essential. If the hip is the source of pain, patients should be counseled that back symptoms will likely improve after hip arthroscopy but not in all cases. EOS imaging to measure sagittal balance may allow the surgeon to predict if impingement measurements on hip x-rays may be underestimated in the setting of a stiff spine. If the patient has multiple risk factors for poor outcomes such as advancing age, articular cartilage damage, borderline dysplasia, hypermobility, on top of a history of multilevel lumbar fusion or spinal deformity, hip arthroscopy may not be ideal and hip arthroplasty should be considered. Clearly, the spine may not be ignored in patients with FAIS.

PURPOSE/OBJECTIVE:The aim of this study was to assess the inter-rater reproducibility and inter-method comparability of hip alpha angle measurements on magnetic resonance imaging (MRI)/magnetic resonance arthrography (MRA) and plain radiographs in patients with femoroacetabular impingement syndrome (FAIS). METHODS:A cross-sectional study of patients who were diagnosed with symptomatic FAIS underwent preoperative MRI/MRA with axial oblique and/or radial plane imaging and had preoperative radiographs with anterior-posterior (AP), 45° Dunn and 90° Dunn views. Alpha angle measurements were performed independently by two musculoskeletal radiologists. Inter-rater reproducibility and inter-method comparability between MRI/MRA images and radiographic views were assessed using the intraclass correlation coefficient (ICC) with 95% confidence interval (CI). RESULTS:Ninety-seven patients were included of whom 93 (95.8%) received axial oblique plane images and 54 (55.6%) had radial plane MRI/MRA images. Inter-rater reproducibility was excellent (ICC > 0.9) for all planes on MRI/MRA and radiographs. MRI/MRA axial oblique images had poor (ICC 0.39, 95% CI [0.09, 0.59]), moderate (ICC 0.57, 95% CI [0.18, 0.75]) and moderate (ICC 0.64, 95% CI [0.20, 0.81]) comparability with AP, 45° Dunn and 90° Dunn, respectively. MRI/MRA radial plane images had equivocal (0 included in all CIs) comparability with AP (ICC 0.66), 45° Dunn (ICC 0.35) and 90° Dunn (ICC 0.14) radiographs. On average, alpha angle measurements were significantly higher with radial images and lower with axial oblique images, when compared to all radiographic views (p < 0.05), except axial oblique versus 45° Dunn views, where angles measured on axial oblique were significantly larger. CONCLUSION/CONCLUSIONS:Alpha angle measurements taken on axial oblique MRI/MRA images show moderate comparability to radiographic 45° Dunn and 90° Dunn views despite negative bias to measurements taken on radiographic AP and 45° Dunn view. Larger alpha angles were appreciated on MRI/MRA radial and axial oblique views compared to radiographic views supporting the inclusion of MRI/MRA alpha angle measurements to properly identify deformity. LEVEL OF EVIDENCE/METHODS:Level II.

BACKGROUND:Hip pain due to femoroacetabular impingement (FAI) is thought to adversely impact sexual satisfaction because of exacerbation of symptoms with hip ROM. However, the effect of FAI on sexual satisfaction and improvement after surgery to treat FAI is largely absent from published studies, despite patients' apparent interest in it as registered by the frequent appearance of these topics on online anonymous discussion platforms. In addition, details regarding its impact on the decision to pursue surgery and the success of hip arthroscopy in alleviating FAI-related sexual dysfunction based on the specific role assumed during intercourse (penetrative versus receptive) remains unknown. QUESTIONS/PURPOSES/OBJECTIVE:Given that sexual intercourse involves different amounts of hip ROM depending on whether patients assume the penetrative or receptive role, this study evaluated the effect of FAI and hip arthroscopy on sexual activity based on role. Compared with patients who participate in the penetrative role during sexual intercourse, do patients who participate in the receptive role (1) experience greater difficulty with sexual function because of FAI symptoms, (2) take longer to return to sexual intercourse after hip arthroscopy, and (3) experience greater improvements in reported sexual function after hip arthroscopy for FAI? METHODS:This was a retrospective cohort study of patients undergoing hip arthroscopy for FAI. Between January 2017 and December 2021, 293 patients were treated with hip arthroscopy for FAI and enrolled in our longitudinally maintained database. Among all patients treated surgically, 184 patients were determined to be potentially eligible for study inclusion based on a minimum follow-up of 6 months postoperatively. The 6-month timepoint was chosen based on published data suggesting that at this timepoint, nearly 100% of patients resumed sexual intercourse with minimal pain after hip arthroscopy. Of the potentially eligible patients, 33% (61 patients) could not be contacted by telephone to obtain verbal consent for participation and 9% (17 patients) declined participation, leaving 106 eligible patients. Electronic questionnaires were sent to all eligible patients and were returned by 58% (61 patients). Forty-two percent of eligible patients (45) did not respond to the questionnaire and were therefore excluded from the analysis. Two percent (2) completed most survey questions but did not specify their role during intercourse and were therefore excluded. The mean age of included patients was 34 ± 9 years, and 56% were women The mean follow-up time was 2 ± 1 years. In total, 63% of included patients reported participating in the receptive role during sexual intercourse (49% receptive only and 14% both receptive and penetrative). Hip symptoms during sexual intercourse preoperatively and postoperatively were evaluated using a questionnaire created by our team to answer our study questions, drawing from one of the only published studies on the matter and combining the questionnaire with sexual position-specific questions garnered from arthroplasty research. Patients who reported participating in the receptive role during intercourse (either exclusively or in addition to the penetrative role) were compared with those who participated exclusively in the penetrative role. There were no specific postoperative recommendations in terms of the timing of return to sexual intercourse, other than to resume when comfortable. RESULTS:Overall, 61% of patients (36 of 59) reported that hip pain somewhat or greatly interfered with sexual intercourse preoperatively. Patients who participated in receptive intercourse were more likely to experience preoperative hip pain that interfered with intercourse than patients who participated exclusively in penetrative intercourse (odds ratio 5 [95% confidence interval 2 to 15]; p < 0.001). Postoperatively, there was no difference in time until return to sexual activity between those in the penetrative group (median 6 weeks [range 2 to 14 weeks]) and those in the receptive group (median 6 weeks [range 4 to 14 weeks]; p = 0.28). Postoperatively, a greater number of patients participating in the penetrative role reported no or very little pain, compared with patients participating in the receptive role (67% [14 of 21] versus 49% [17 of 35]). However, with regard to preoperative to postoperative improvement, patients who participated in the receptive role had greater pain with positions involving more hip flexion and abduction and experienced a greater improvement than their penetrative counterparts in these positions postoperatively. Despite this improvement, however, 33% of patients (7 of 21) participating in the penetrative role and 51% of patients (18 of 35) participating in the receptive role continued to report either some or a great amount of pain at final follow-up. CONCLUSION/CONCLUSIONS:Hip pain secondary to FAI interferes with sexual relations, particularly for partners who participate in the receptive role. Postoperatively, both patients participating in receptive and penetrative intercourse resumed sexual intercourse at a median of 6 weeks. After hip arthroscopy, the greatest improvement in pain was seen in receptive partners during sexual positions that involved more hip flexion and abduction. Despite this improvement, most patients, regardless of sexual role assumed, reported some degree of residual pain. Patients planning to undergo arthroscopic surgery for FAI, particularly those who participate in receptive intercourse, should be appropriately counseled about reasonable postoperative expectations based on our findings. LEVEL OF EVIDENCE/METHODS:Level III, therapeutic study.

PURPOSE/OBJECTIVE:To investigate the patient reported outcomes (PROs) of patients undergoing hip arthroscopy (HA) for femeroacetabular impingement syndrome (FAIS), a condition where irregular bone growth in the hip joint leads to friction and pain during movement, who have worker's compensation (WC) or no-fault insurance (NF) versus commercial insurance (CI) at both 2 year and 5 year follow-up. METHODS:This was a single center, single surgeon, retrospective analysis performed between August 2007 and May 2023 of consecutive patients that underwent HA, a minimally invasive surgical procedure used to diagnose and treat problems inside the hip joint through small incisions, for FAIS. Patients were divided into two cohorts-those with WC/NF and those with commercial insurance (CI). Patient reported outcomes (PROs), which included modified Harris Hip Score (mHHS) and Non-Arthritic Hip Score (NAHS), were collected preoperatively, as well as at least 2-year postoperatively. Additionally, other clinically relevant outcomes variables including prevalence of revision surgery and conversion to total hip arthroplasty were recorded. RESULTS: = 0.148). The WC/NF cohort had a lower rate of achieving Substantial Clinical Benefit (SCB) for mHHS at 2-years follow-up (66.7% vs. 84.1%, p = 0.02).The rate of revision hip arthroscopy was significantly higher in the worker's compensation/no fault cohort than the commercial insurance cohort (15.6% vs. 3.5%, p < 0.01). The rate of conversion to total hip arthroplasty (THA) in the WC/NF cohort was not significantly different than the rate of conversion to THA in the commercial insurance cohort (0.0% vs. 3.2%, p = 0.30). CONCLUSION/CONCLUSIONS:Patients with WC/NF insurance may expect a significant improvement from baseline mHHS and NAHS following HA for FAIS at short-term follow-up. However, this improvement may not be as durable as those experienced by patients with CI. Additionally, WC/NF patients should be counseled that they have a higher risk of undergoing revision hip arthroscopy than similar CI patients. LEVEL OF EVIDENCE/METHODS:III, Retrospective Comparative Prognostic Investigation.

PURPOSE/OBJECTIVE:To examine the associations between hip labral width and patient-reported outcomes, clinical threshold achievement rates, and rate of reoperation among patients with femoroacetabular impingement syndrome (FAIS) who underwent hip arthroscopy and labral repair at minimum 5-year follow-up. METHODS:Patients were identified from a prospective database who underwent primary hip arthroscopy for treatment of labral tears and FAIS. Modified Harris Hip Score (mHHS) and Nonarthritic Hip Score (NAHS) were recorded preoperatively and at 5-year follow-up. Achievement of the minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient-acceptable symptom state (PASS) was determined using previously established values. Labral width MRI measurements were performed by two independent readers at standardized "clockface" locations. Patients were stratified into three groups at each position: lower-width (<½ SD below mean), middle-width (within ½ SD of mean), and upper-width (>½ SD above mean). Multivariable regression was used to evaluate associations of labral width with patient-reported outcomes and reoperation rate. RESULTS:Seventy-three patients (age: 41.0±12.0 years; 68.5% female) were included. Inter-rater reliability for labral width measurements was high at all positions (ICC: 0.94-0.96). There were no significant inter-group differences in mHHS/NAHS improvement (p>0.05) or in achievement rates of MCID/SCB/PASS at each clockface position (p>0.05). Eleven patients (15.1%) underwent arthroscopic revision and four patients (5.5%) converted to THA. Multivariable analysis found lower-width groups at 11:30 (OR: 1.75, p=0.02) and 3:00 (OR: 1.59, p=0.04) positions to have increased odds of revision within 5 years, however, labral width was not associated with 5-year improvement in mHHS/NAHS, achievement of MCID/PASS/SCB, or conversion to THA (p>0.05). CONCLUSION/CONCLUSIONS:Hip labral width <½ SD below the mean measured on preoperative MRI at 11:30 and 3:00 clockface positions was associated with increased odds of reoperation after arthroscopic labral repair and treatment of FAIS. Labral width was not associated with 5-year improvement of mHHS, NAHS, achievement of clinical thresholds, or conversion to arthroplasty. LEVEL OF EVIDENCE/METHODS:Level IV, case series.