Symptomatic Hip Research Articles

Multifid Iliopsoas Tendons Are More Common in Patients With Painful Snapping Iliopsoas Tendons

To retrospectively determine the prevalence of multifid tendons in a population of patients who underwent iliopsoas release for painful snapping iliopsoas tendons. Patients who underwent iliopsoas release for painful snapping iliopsoas tendons were retrospectively identified from a database of patients who had undergone arthroscopic hip surgery performed by a single surgeon between 2011 and 2020. Patients who had incomplete data or who underwent prior fracture fixation, joint arthroplasty, pelvic surgery, or other interventions for snapping hip were excluded. Magnetic resonance imaging (MRI) and operative reports were reviewed and compared with those of an age-matched control group of patients who had undergone hip or pelvic MRI examinations in the past year for different indications. This study included 91 patients (78 female and 13 male patients; mean age, 23.3 years) who were treated operatively for painful snapping hip and 78 controls (54 female and 24 male patients; mean age, 28.4 years) who received hip or pelvic MRI for other indications. Among the patients who underwent iliopsoas release, there were 5 unifid iliopsoas tendons (5.5%) compared with 86 multifid iliopsoas tendons (94.5%) when classified with MRI whereas operative examination showed 19 unifid tendons (20.9%) compared with 72 multifid tendons (79.1%, P < .001). When the MRI scans of the operative group were compared with the MRI scans of the control group, the patients who underwent surgery for painful snapping hip had a higher rate of multifid tendons (94.5% of operative hips compared with 69.2% of control right hips [P< .001] and 74.4% of control left hips [P < .001]). However, when the operative reports were used to classify the iliopsoas tendon, there was no significance between the operative and control groups (79.1% of operative hips had multifid tendons compared with 69.2% of control right hips [P= .141] and 74.4% of control left hips [P= .464]). For patients with symptomatic snapping hip undergoing iliopsoas lengthening, multifid iliopsoas tendons are more prevalent than in a control population. Level IV, prognostic case series.

Which Acetabular Measurements Most Accurately Differentiate Between Patients and Controls? A Comparative Study.

Which Acetabular Measurements Most Accurately Differentiate Between Patients and Controls? A Comparative Study.

Treatment of Symptomatic Residual Deformity in Legg-Calvé-Perthes Disease: Mid-Term Outcomes and Predictors of Failure After Surgical Hip Dislocation with Femoral-Head Reshaping and Relative Neck Lengthening.

Treating patients with symptomatic hips after healed Legg-Calvé-Perthes disease (LCPD) is challenging, mainly because of the complexity of the deformity. We performed a retrospective study to evaluate clinical and radiographic outcomes, measure the survival rate, and identify predictors of failure following a surgical hip dislocation (SHD) with femoral-head reshaping and relative femoral-neck lengthening for the treatment of symptomatic residual hip deformity after healed LCPD. We identified 60 patients undergoing SHD for the treatment of symptomatic residual LCPD deformity. Fifty-one (85%) of the patients (mean age, 16.3 ± 4.7 years; 21 male patients [41%]), were followed ≥4 years after surgery. We defined surgical failure as conversion to, or recommendation for, total hip arthroplasty (THA) or a Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score of ≥10 at the most recent follow-up. We used a multivariable Cox proportional hazards model to identify factors that were predictive of failure. The rate of survival free from failure was estimated using a Kaplan-Meier curve. Twenty (39%) of the patients met 1 of the end-point criteria for surgical failure, while the hips of the remaining 31 (61%) of the patients were successfully preserved at a median follow-up of 10.2 years (interquartile range, 5.7 to 12.9 years). The estimated survival was 80% (95% confidence interval [CI] = 70% to 92%) at 5 years and 66% (95% CI = 53% to 81%) at 10 years. Independent factors associated with surgical failure were the severity of preoperative pain as assessed by the WOMAC pain score (hazard ratio [HR] = 1.16; 95% CI = 1.03 to 1.30; p = 0.01) and the severity of the deformity as assessed by the anteroposterior alpha angle (HR = 1.06; 95% CI = 1.01 to 1.11; p = 0.01). We found that SHD with relative femoral-neck lengthening and osteochondroplasty of the femoral head-neck junction was associated with improved deformity as assessed radiographically and decreased pain and symptoms of stiffness among patients with symptomatic residual LCPD deformity. Preoperative pain and deformity were identified as predictors of surgical failure. Further research is needed to establish the role of SHD and other procedures in preserving the hip over the long term. Therapeutic L evel IV . See Instructions for Authors for a complete description of levels of evidence.

Acetabular Sector Angles in Asymptomatic and Dysplastic Hips: Defining Dysplasia and Thresholds to Guide Management.

Radiographic evaluation plays an important role in detecting and grading hip dysplasia. Acetabular sector angles (ASAs) measure the degree of femoral head coverage provided by the acetabulum on computed tomographic (CT) scans. In this study, we aimed to determine ASA values at different axial levels in a control cohort with asymptomatic, high-functioning hips without underlying hip pathology and a study group with symptomatic, dysplastic hips that underwent periacetabular osteotomy (PAO), thereby defining the ASA thresholds for hip dysplasia. This was a cross-sectional study evaluating a control group of 51 patients (102 hips) and a study group of 66 patients (72 hips). The control group was high-functioning and asymptomatic, with an Oxford Hip Score of >43, did not have osteoarthritis (Tönnis grade ≤1), underwent a pelvic CT scan, had a mean age (and standard deviation) of 52.1 ± 5.5 years, and was 52.9% female. The study group had symptomatic hip dysplasia treated with PAO, had a mean age of 29.5 ± 7.3 years, and 83.3% was female. Anterior ASA (AASA) and posterior ASA (PASA) were measured at 3 axial CT levels to determine equatorial, intermediate, and proximal ASA. The thresholds for dysplasia were determined using receiver operating characteristic (ROC) curve analysis, including the area under the curve (AUC). Patients with dysplasia had significantly smaller ASAs compared with the control group; the differences were most pronounced for proximal AASAs and proximal and intermediate PASAs. The control group had a mean proximal PASA of 162° ± 17°, yielding a threshold for dysplasia of 137° (AUC, 0.908). The mean intermediate PASA for the control group was 117° ± 11°, yielding a threshold of 107° (AUC, 0.904). The threshold for anterior dysplasia was 133° for proximal AASA (AUC, 0.859) and 57° for equatorial AASA (AUC, 0.868). The threshold for posterior dysplasia was 102° for intermediate PASA (AUC, 0.933). Measurement of ASA is a reliable tool to identify focal acetabular deficiency with high accuracy, aiding diagnosis and management. A proximal PASA of <137° or an intermediate PASA of <107° should alert clinicians to the presence of dysplasia. Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Age and magnitude of acetabular correction impair bone healing after triple pelvic osteotomy.

The aim of this examination was to assess, which risk factors impair bone healing after triple pelvic osteotomy (TPO) in the treatment of symptomatic hip dysplasia. A consecutive series of 241 TPO was reviewed retrospectively. Of these, a set of five postoperative radiographs was available, performed in a standardized regimen in the first year after surgery. Two experienced observers had to agree on the existence of a non-union on the radiographs obtained 1year after TPO. Both observers measured the lateral center edge angle (LCEA) and acetabular index (AI) on all radiographs. Besides patient-specific risk factors, the magnitudes of acetabular correction and the amounts of a detectable slight change in acetabular correction were assessed. Binary logistic regression analysis and chi-squared test were used to detect the impact of the risk factor on bone healing. A total of 222 cases were left for further examination. In 19 of these, at least one osteotomy was not healed completely one year after surgery. Binary logistic regression showed a significant relationship between the risk factors "age" (p < 0.001; odds ratio (OR) 1.109 (95% CI 1.05-1.18)) as well as "magnitude of acetabular correction (LCEA)" (p = 0.01; OR 1.087 (95% CI 1.02-1.16)) and non-union. Pearson's chi-square test showed a relationship between the risk factor "wound healing disorder" and non-union (p < 0.001). LCEA and AI showed a slight increase from the first to the last follow-up (observer 1: 1.6° and 1.3°, resp.), but regression analysis for the risk factor "amount of postoperative change of acetabular correction (LCEA, AI)" did not show statistically significant values. The age at surgery and the magnitude of acetabular correction negatively influenced the healing progress of the osteotomy sites. The amount of a slight postoperative change of LCEA and AI did not correlate with a non-union.

Poster 218: Hip Arthroscopy Improves Sexual Function in Receptive Partners with Femoroacetabular Impingement Syndrome in Positions of Flexion and Abduction

Objectives: 1) To evaluate if femoracetabular impingement syndrome (FAI) interferes with sexual relations and influences patientdecision to pursue surgical intervention. 2) To determine when patients return to sexual intercourse after hip arthroscopy for the treatment of FAI. 3) To compare preoperative to postoperative improvement in pain experienced during sexual intercourse based on sexual role assumed (receptive or penetrative) and position. Methods: This was a retrospective cohort study of patients undergoing hip arthroscopy for FAI between January 2019 and January 2022. Hip symptoms during sexual intercourse were evaluated using a Likert- style questionnaire. Patients were also asked to rate the severity of their hip pain with 12 common sexual positions before and after surgery. Patients who primarily participate as the penetrative role during intercourse were compared to those who participate as the receptive role. The difference in preoperative and postoperative pain experienced with each position was assessed using a series of Wilcoxon signed-rank tests for ordinal data. To confirm the results, each comparison was also evaluated using a series of ordered logistic regressions. Results: Sixty-one patients with a mean age of 33.8 +/- 8.48 and a mean follow up time of 1.96 +/- 0.88 years were included in the analysis. 47.5% of patients primarily assume the receptive role during sexual intercourse (36.1%: penetrative role; 13.1%: both). A significantly greater proportion of patients participating in receptive intercourse reported hip symptoms that interfered with sexual intercourse compared to patients participating in penetrative intercourse ( p =.007). Furthermore, a greater proportion of patients in the receptive group reported that the hip pain during intercourse contributed to the decision to pursue hip surgery ( p =.009) (Table 1). Following surgery, 94.9% of patients had returned to sexual intercourse by the time of latest follow up. These patients resumed sexual intercourse at a mean of 7.6 +/- 3.4 weeks postoperatively. There was no difference in time to resume intercourse between patients participating in receptive intercourse and those participating in penetrative intercourse ( p = 0.277) (Figure 1). Overall, 52.2% of patients reported no pain or little pain with sexual intercourse at the time of latest follow up. Patients in the receptive group continued to report worse pain symptoms during intercourse compared to the penetrative group postoperatively. However, these patients experienced significantly greater improvement in preoperative to postoperative symptomatology during intercourse, specifically in sexual positions involving greater degrees of flexion and abduction (Figures 2, 3). For patients assuming the penetrative role during intercourse, there was no difference in hip pain after surgery based on sexual position (Figure 2, 4). Conclusions: Hip pain secondary to FAI interferes with sexual intercourse, particularly for patients who participate in the receptive role, and it influences their decision to undergo hip arthroscopy. These patients experience pain specifically in sexual positions involving greater degrees of flexion and abduction. Hip arthroscopy successfully improves the pain experienced while participating in these positions postoperatively.

Poster 119: MRI evidence of labral tears in healthy young athletes without hip pain

Objectives: The prevalence of labral tears in asymptomatic active adults has been reported, but the prevalence of labral tears and other incidental hip lesions in the asymptomatic adolescent population has not yet been determined. The purpose of this study was to determine the prevalence of hip abnormalities detected on 3T MRI in an active adolescent population with no hip symptoms and, secondarily to compare with hip abnormalities found in adolescents who underwent an MRI for a hip related condition. Methods: Following IRB approval, adolescent patients presenting with isolated knee pain requiring knee MRI were prospectively recruited to have a 3T MRI of their asymptomatic contralateral hip (ASx). A comparison group of adolescent subjects who underwent an MRI for hip pain was enrolled retrospectively (Sx). All MRI scans were anonymized and randomized. Based on preliminary power analysis, 50 subjects were enrolled for each cohort. Blinded to the patient’s cohort status, clinical and demographic data, 2 fellowship-trained musculoskeletal radiologists evaluated these MRI’s independently for abnormal hip lesions, including labral tears. Inter-reader reliability was evaluated using Cohen’s Kappa. A chi-square or Fisher’s exact test was used to compare the prevalence of these hip lesions between the two cohorts. Results: Average patient age was 14.9 years for both cohorts (range 9-18 years); 52% were female. In the ASx group, incidental labral tears were found in 18%, labral/paralabral cysts 6%, cartilage lesion 0%, subchondral cyst 0%, ligamentum teres tear 0%, femoral fibrocystic change 0%, cam lesion 30%, acetabular bone edema 0%, acetabular rim fracture 0%. The prevalence of labral tears (30%, P-value 0.160) and cam lesion (36%, P-value 0.523) in the Sx group was not significantly different from that of the ASx cohort. Conclusions: Labral tears were present on 3T MRI’s of adolescents with and without hip pain. While MRI is essential to confirm the surgeon’s suspicion and to detect unexpected pathology, clinical exam and history are crucial in pinpointing clinically relevant abnormal imaging findings. [Table: see text]

Paper 63: Return to Long Distance Running After Hip Arthroscopy for Femoroacetabular Impingement

Objectives: Arthroscopic hip surgery for femoroacetabular impingement (FAI) has shown high rates of return to different sports in athletes. No studies to date have focused on patients’ return to long- distance running, a running sport with unique characteristics and demands. The purpose of this study was to determine return to long-distance running rates and changes in running performance in long distance runners undergoing hip arthroscopic surgery for the treatment of FAI and to identify possible risk factors associated with not returning to long distance running. Methods: An institutional hip preservation registry was retrospectively reviewed for patients identified as long distance runners (half marathons and marathons) who underwent primary hip arthroscopies for FAI performed between March 2010 and January 2017. Patient demographics and injury characteristics as well as clinical and radiographic findings were recorded. All patients were contacted for return to running information using a running specific return to sport questionnaire. Multivariable logistic regression analysis was used to identify potential risk factors for not returning to long-distance running. Results: Sixty-eight long distance runners (78 hips) were included. Mean patient age and body mass index (BMI) were 37.8±8.9 years and 23.8±3.3 kg/m2, respectively. Thirty-eight (56%) were female runners. Mean weekly running milage prior to injury was 34.5±16.9 miles. Mean duration of hip symptoms prior to seeking medical evaluation was 77.3±16.9 weeks. Fifty-nine runners (87%) had to stop or modify their running for a mean duration of 44.3±45 weeks prior to surgery due to hip symptoms. Overall, 50 runners (74%) returned to any running, of which 25 runners (50%) returned to long distance running completing half/full marathons races after surgery. Most common reasons for not returning to running were pain or discomfort (50%) followed by fear of re-injury (22%) and additional different injuries (22%). Among runners who did not return to any running, 12 (67%) reported satisfaction from surgery. Multivariable logistic regression analysis revealed female runners (odds ratio [OR]=0.2; confidence interval [CI]=0.0 to 0.9; p=0.034) and hips with radiologic findings of higher alpha angles (OR=0.9; 95% CI=0.9 to 1.0; p=0.045) were less likely to return to long distance running. Conclusions: Hip arthroscopic treatment for FAI in symptomatic long-distance runners, a distinctive subgroup of runners, allowed most of them (74%) to return to running, however only 40% returned to long distance running races. Female runners and runners with radiologic findings of higher alpha angles were less likely to return to long-distance running. These data can better guide clinicians and long- distance runners with realistic expectations related to the arthroscopic management of symptomatic FAI.

Decision Making in Combined Hip Arthroscopy and Femoral Derotational Osteotomy Surgeries

Background: Femoral version abnormalities can contribute to intra-articular hip pathology. Combined hip arthroscopy with femoral derotational osteotomy (FDRO) has been shown to successfully treat those with intra-articular hip pathology with excessive anteversion or retroversion of the femur. Indications: We describe the technique for combined hip arthroscopy and FDRO in patients with symptomatic intra-articular hip pathology in the setting of excessive anteversion or retroversion of the femur. Technique Description: Hip arthroscopy is performed using standard anterolateral, modified mid-anterior, and distal anterolateral accessory portals. The labrum is repaired using a narrow diameter suture. Femoroplasty is performed with utilization of fluoroscopic imaging to assess resection. Dynamic flexion is performed as a final check of adequacy of resection. Capsular closure is performed in all cases. After hip arthroscopy, the patient is repositioned on a radiolucent table. A piriformis start point is obtained with a guide pin followed by standard opening reaming and ball-tipped guidewire placement. A femoral osteotomy is made just proximal to the isthmus and made through a lateral approach to the femur. Two K-wires are placed distal and proximal to the osteotomy site. A goniometer is then used to measure rotation. A drill is used to perforate the cortex circumferentially at the osteotomy site. After standard reaming, a sagittal saw is then used to start the osteotomy cut followed by an osteotome. An intramedullary nail is inserted over a ball-tipped guidewire while rotational reduction is assessed from the foot of the operating table. Distal interlocking screws are placed, and the nail is backslapped to create compression at the osteotomy site prior to placing proximal interlocking screws. Results: Recent studies show improved hip outcome scores in patients who undergo concomitant hip arthroscopy and FDRO for symptomatic abnormal femoral version. Discussion/Conclusion: Identifying patients who would benefit from concomitant surgeries requires thorough preoperative evaluation. Correct identification and treatment of these patients leads to improved outcomes. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Poster 113: Epigenetic Regulation of PPARγ Rescues Articular Chondrocytes from Catabolic State Suggesting PPARγ as a Potential Target to Slow Down Progression of OA in Hip FAI

Objectives: Hip Femoroacetabular impingement (FAI) has a high prevalence of chondral lesions, and the severity of chondral damage is associated with an increased risk of postoperative OA progression, but the mechanisms of cartilage degeneration in OA progression remains unclear. Peroxisome proliferator- activated receptor-gamma (PPARγ) is widely expressed in healthy articular chondrocytes (ACs) and plays an essential role in cartilage homeostasis. Recent investigations into OA pathogenesis have revealed that hyper or hypomethylation (by DNMTs) of OA susceptibility genes are involved in OA progression, especially downregulation of PPARγ has been linked to OA progression. This study aimed to investigate the expression of PPARγ and DNA methyltransferases enzymes (DNMT1 and DNMT3A) during progression of hip disease and 2) methylation changes in the PPARγ promoter area during progression of hip disease. Methods: Full-thickness cartilage samples were collected from the impingement zone. Twelve patients underwent hip preservation surgery for cam FAI (early FAI) and twelve patients underwent total hip replacement for advanced OA secondary to cam FAI (late FAI-OA) were included. As a non-disease (ND) group, six healthy samples were procured from hip joint cadavers. Cartilage explants were cultured in unstimulated conditions or catabolic stimulus (IL1β) with or without DNA demethylating agent 5-Aza-2’- deoxycytidine (5Aza). Histological analysis was performed with safranin O/fast green. Gene expression was analyzed via qPCR for GAPDH, DNMT1, DNMT3A, PPARγ, MMP13, and COL10A1. Methylation specific PCR (MSP) was performed to assess the methylation status at PPARγ promoter site. Chromatin immunoprecipitation (ChIP) assay was performed to confirm an interaction between DNMT3A and the PPAR promoter region. Results: The early FAI group included younger subjects than the late FAI OA group. Cartilage samples in early and late FAI-OA displayed a histological OA phenotype (Figure 1A). ACs in early and late FAI-OA displayed increased expression of catabolism and chondrocyte hypertrophy markers ( MMP13: ND vs early p&lt;0.001, ND vs late p&lt;0.001, COL10A1: ND vs early p&lt;0.001, ND vs late p&lt;0.001, Figure. 1B). Contrary, expression of PPARγ gradually declined as the disease progressed (ND vs early p=0.001, early vs late p=0.003, Figure. 1B). IF analysis also displayed a gradual decrease of the PPARγ expression during disease progression (ND vs early p=0.001, early vs late p=0.041, Figure 1C). In the assessment of the epigenetic mechanisms of aberrant DNA methylation in OA progression, overexpression of DNMT1 and DNMT3A levels was observed with disease progression in RT-PCR ( DNMT1: ND vs early p&lt;0.001, early vs late p=0.041, DNMT3A: ND vs early p=0.015, early vs late p=0.053,Figure 2A) and IF analysis ( DNMT1: ND vs early p&lt;0.001, early vs late p&lt;0.001, DNMT3A: ND vs early &lt;0.001, early vs late p=0.008, Figure 2B). Next, in MSP analysis, human PPARγ promoter was featured by typical CpG islands (Figure 3A). As the OA progresses, hypermethylation at PPARγ promoter (ND: 9%, Early-FAI: 34%, Late FAI-OA: 48%) was observed (Figure 3B), and ChIP assay confirmed DNMT3A interaction with the CpG PPARγ promoter area (Figure 3C). IL1β stimulus increased PPARγ promoter methylation for early (34% to 57%, p=0.016, Figure 3D) and late stages (48% to 79%, p=0.001, Figure 3D) resulting in suppression of PPARγ expression (P=0.073, Figure 3F). Contrary, treatment with 5Aza (a DNA demethylator) brought the level of methylation back to 37% for early FAI ( p=0.033, Figure 3D) and 46% for late FAI-OA (p&lt;0.001, Figure 3D), reversed the PPARγ suppression induced by IL1β (early- FAI p=0.009, and late FAI-OA ACs p&lt;0.001 Figure 3F) and decreased expression of MMP-13 and COL10A1 induced by IL1β (early-FAI p=0.009, Figure 4C and late FAI-OA ACs p&lt;0.001 Figure 3F). PPARγ inhibitor rescued cells from the catabolic phenotype. (Fig.3E, F), suggesting that restoration of PPARγ by 5Aza contributes significantly to the cartilage protective effect. Conclusions: This current study demonstrates that PPARγ expression was gradually suppressed via promoter hypermethylation during OA progression in hip FAI. Moreover, the inflammatory stimulus with IL1β further increased catabolic markers and enhanced PPARγ suppression via promoter excessive hypermethylation in human hip ACs. Notably, DNA demethylating agent (5 aza) prevents the IL1β induced PPARγ promoter hypermethylation rescuing PPARγ and alleviating cartilage degenerative damage. Certainly, for patients with symptomatic hip FAI, surgical correction should be prioritized to suppress inflammation, but our observations suggests that critical epigenetic dysregulation occurs during the progression of hip OA. Future investigations will be needed to confirm if regulation of these epigenetic changes could potentially complement surgical treatment to minimize OA progression in hip FAI.

Improved Functional Outcomes of Combined Hip Arthroscopy and Periacetabular Osteotomy at Minimum 2-Year Follow-Up

To evaluate patient-reported outcomes (PROs) and survivorship at minimum 2-year follow-up after combined hip arthroscopy and periacetabular osteotomy (PAO) performed in the setting of a single anesthetic event. Patients who underwent combined hip arthroscopy (M.J.P.) and PAO (J.M.M.) between January 2017 and June 2020 were identified. Preoperative and minimum 2-year postoperative PROs including Hip Outcome Score-Activities of Daily Living (HOS-ADL), HOS-Sport, modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Osteoarthritis Index, 12-Item Short Form Survey Mental Component Scores (SF-12 MCS), and 12-Item Short Form Survey Physical Component Score were collected and compared in addition to revision rate, conversion to total hip arthroplasty (THA), and patient satisfaction. Twenty-four of 29 patients (83%) eligible for the study were available for 2-year minimum follow-up with a median follow-up time of 2.5 years (range, 2.0-5.0). There were 19 females and 5 males with mean age of 31 ± 12 years. Mean preoperative lateral center edge angle was 20° ± 5° and alpha angle was 71° ± 11°. One patient underwent reoperation for removal of a symptomatic iliac crest screw at 11.7 months after operation. Two patients, a 33-year-old woman and a 37-year-old man, were converted to THA at 2.6 and 1.3 years, respectively, following the combined procedure. Both patients had a Tönnis grade of 1 on radiographs, as well as bipolar Outerbridge grade III/IV defects requiring microfracture of the acetabulum. For patients who did not convert to THA (n= 22), there was significant improvement from before to after surgery for all scores (P<.05) except SF-12 MCS. The minimal clinically significant difference and patient-acceptable symptom state rates for HOS-ADL, HOS-Sport, and mHHS were 72%, 82%, 86%, and 95%, 91%, and 95%, respectively. Median patient satisfaction was 10 (range, 4 to 10). Single-stage combined hip arthroscopy with periacetabular osteotomy for patients with symptomatic hip dysplasia results in improvement in PROs and arthroplasty free survivorship of 92% at median 2.5 year follow-up. Level IV, case series.

Bilateral simultaneous hip arthroplasty shows comparable early outcome and complication rate as staged bilateral hip arthroplasty for patients scored ASA 1-3 if performed by a high-volume surgeon

PurposeThe aim of this study was to compare early outcomes after simultaneous and staged hip arthroplasty (THA) in patients with bilateral symptomatic pathology.MethodsWe conducted a retrospective cohort study including all patients scheduled for primary THA for bilateral hip osteoarthritis (OA, n = 290). Patients either received simultaneous (n = 152, 52.4%) or staged (n = 138, 47.6%) bilateral THA based on individual preference. All operations (n = 428) were performed by one single, high-volume surgeon. Demographic data (e.g., age, ASA score) as well as perioperative parameters (haemoglobin drop (Hb), red blood cell transfusion, length of stay (LOS), operation time, six week complication rate and achievement of inpatient rehabilitation key points) were evaluated.ResultsPatients in the simultaneous bilateral THA group were younger (62.8 ± 8.9 vs. 65 ± 9.7 years, p = 0.022) and had lower ASA scores (1.8, (34.2% ASA 1, 55.3% ASA 2, 37.2% ASA 3) vs. 2.0 (18.8% ASA 1, 61.6% ASA 2, 19.6% ASA 3)) than the staged group. While the average LOS was 7.1 ± 1.7 days for simultaneous bilateral THA, the combined LOS for the staged group was 12.9 ± 2.4 days (p < 0.001). The cumulative operation time in the simultaneous bilateral THA group was 61.1 ± 11.5 min and 57.6 ± 7.3 min in the staged group (p < 0.015). Cumulative Hb loss was significantly higher in the staged group (2.1 ± 7.2 g/dl vs. 3.7 ± 1.3 g/dl, p < 0.001). No significant differences were found concerning the complication rate or early inpatient rehabilitation.ConclusionSimultaneous bilateral hip arthroplasty in patients with symptomatic bilateral hip osteoarthritis is as safe and successful as a staged procedure if performed by a high-volume surgeon.

INFLUENCE OF ACETABULAR AND FEMORAL MORPHOLOGY ON PELVIC TILT: A STUDY IN 388 PATIENTS

To investigate whether anterior pelvic plane-pelvic tilt (APP-PT) is associated with distinct hip pathomorphologies, we asked: (1) Is there a difference in APP-PT between symptomatic young patients eligible for joint preservation surgery and an asymptomatic control group? (2) Does APP-PT vary between distinct acetabular and femoral pathomorphologies? (3) Does APP-PT differ in symptomatic hips based on demographic factors?IRB-approved, single-center, retrospective, case-control, comparative study in 388 symptomatic hips (357) patients (mean age 26 ± 2 years [range 23 to 29], 50% females) that presented to our tertiary center for joint preservation over a five year-period. Patients were allocated to 12 different morphologic subgroups. The overall study group was compared to a control group of 20 asymptomatic hips (20 patients). APP-PT was assessed in all patients based on AP pelvis X-rays using the validated HipRecon software. Values between overall and control group were compared using an independent samples t-test. Multiple regression analysis was performed to examine the influences of diagnoses and demographic factors on APP-PT. Minimal clinically important difference (MCID) of APP-PT was defined as &gt;1 standard deviation.No significant differences in APP-PT between the control group and overall group (1.1 ± 3.0° [−4.9 to 5.9] vs 1.8 ± 3.4° [−6.9 to 13.2], p = 0.323) were observed. Acetabular retroversion and overcoverage groups showed higher APP-PT compared to the control group (both p &lt; 0.05) and were the only diagnoses with significant influence on APP-PT in the stepwise multiple regression analysis. However, all observed differences were below the MCID. Demographic factors age, gender, height, weight and BMI showed no influence on APP-PT.APP-PT across different hip pathomorphologies showed no clinically significant variation. It does not appear to be a relevant contributing factor in the evaluation of young patients eligible for hip preservation surgery.

THIRTY-YEAR FOLLOW-UP STUDY OF ROTATIONAL ACETABULAR OSTEOTOMY

Satisfactory intermediate and long-term results of rotational acetabular osteotomy (RAO) for the treatment of early osteoarthritis secondary to developmental dysplasia of the hip have been reported. The purpose of this study is to examine the 30-year results of RAO.Between 1987 and 1994, we treated 49 patients (55 hips) with RAO for diagnosis of pre- OA or early-stage OA. Of those patients, 35 patients (43 hips) were available at a minimum of 28 years. The follow-up rate was 78.2% and the mean follow-up was 30.5 years. The mean age at the time of surgery was 34 years. Clinical evaluation was performed with the Merle d'Aubigne and Postel rating scale, and radiographic analyses included measurements of the center-edge angle, acetabular roof angle, and head lateralization index on preoperative, postoperative AP radiographs of the pelvis. Postoperative joint congruency was classified into four grades. The radiographic evidence of progression of OA was defined as the minimum joint space less than 2.5mm.The mean preoperative clinical score was 14.0, which improved to a mean of 15.3 at the time of the latest follow-up. The mean center-edge angle improved from 0.6° preoperatively to 34° postoperatively, the mean acetabular roof angle improved from 28.4°preoperatively to 1.0°postoperatively, the mean head lateralization index improved from 0.642 preoperatively to 0.59 postoperatively. Postoperative joint congruency was excellent in 11 hips, good in 29 hips, and fair in 3 hips. Nineteen patients (20 hips) had radiographic OA progression, and 10 patients (11 hips) were converted to THA. Kaplan-Meier survivorship analysis, with radiographic OA progression as the end point, predicted survival of 75.6% at 20 years and 48.8% at 30 years, and with THA conversion as the end point, 90.2% at 20 years and 71.2% at 30 years.The RAO is an effective surgical procedure for symptomatic dysplastic hips of pre- and early-stage OA and could change the natural history of the dysplastic hip.

Acetabular Rim Ossification Variants Are Found in Almost 20% of Patients Presenting With Hip Pain

To determine the prevalence of 4 different types of acetabular rim ossifications, including partial labral ossification or punctate calcification, true os acetabuli, acetabular rim stress fracture, and complete labral ossification, and to determine whether different types of periacetabular ossifications are linked to demographic or radiological factors. We retrospectively reviewed the medial records of patients presenting for hip-related complaints at 2 sports medicine practices from September 2007 to December 2009. An anteroposterior radiograph of both hips and a lateral radiograph of each hip was obtained for all patients and reviewed for findings of cam and pincer femoroacetabular impingement, degenerative changes (Tönnis grade), and periacetabular calcifications for both hips. These parameters were also evaluated with respect to symptoms, sex, and age. Four hundred ninety-one consecutive patients (982 hips) presented to 2 orthopaedic surgeons at 2 centers for "hip"-related complaints. There were 223 males and 268 females (age 39 ± 14 years). The overall prevalence of periacetabular calcifications in hips was 17.6%, with 56.6% of calcifications in the symptomatic hip and 43.4% in the contralateral hip. Four basic patterns of calcification were identified: punctuate calcifications within the labrum (8.0% hips), large rounded calcifications (os acetabuli) (4.2% hip), large fragments with a vertical line of the superior-lateral acetabular rim, consistent with healed or non-healed stress fracture (2.0% hips), and complete ossification of the labrum (3.4% hips). Overall, male sex (P= .002), increased lateral center-edge angle (P= .046), and higher Tönnis grade (P < .001) statistically predicted the presence of periacetabular ossification. Punctate calcifications were more prevalent in males (P= .002). Higher Tönnis grade (P=.029) and increased alpha angle (P= .046) were more prevalent with os acetabuli. Younger age (P= .001), male sex (P= .048), increased alpha angle (P= .012), and increased lateral center-edge angle (P < .001) were more prevalent in acetabular rim fractures. No factors were statistically significant at predicting the presence of an ossified labrum. Periacetabular calcifications are not uncommon. Four particular patterns of calcification are identified: punctate labral calcifications (8%), larger rounded calcifications (i.e., os acetabuli) (4.2%), acetabular rim stress fractures (2%), and complete ossification of the labrum (3.4%) for a combined prevalence of 17.6% in patients presenting to an orthopaedic surgeon with "hip"-related complaints. Nearly half were in the asymptomatic hip. Male sex had a higher prevalence of periacetabular calcifications. An increased lateral center edge angle and higher Tönnis grade also had a higher prevalence of periacetabular calcifications. Younger male patients are more likely to have acetabular rim stress fractures. Patients with an increased alpha angle have a higher prevalence of os acetabuli and rim stress fractures. This study aims to identify, quantify, and categorize periacetabular calcifications about the hip. Their clinical relationships and relevance have been discussed, but no study has distinctly categorized the various types and their prevalence. This study provides a framework for identification and categorization.

Intra- and inter-rater reliability, agreement, and minimal detectable change of the handheld dynamometer in individuals with symptomatic hip osteoarthritis.

The handheld dynamometer has been validated to measure muscle strength in different muscle groups. However, to date, it has not been tested in individuals who experience pain induced by hip osteoarthritis. The current study aimed to evaluate the intra- and inter-rater reliability, agreement, and minimal detectable change of the Lafayette handheld dynamometer, model 1165, to assess the peak force (Pk) and average peak force (Af) of hip muscles in individuals with symptomatic hip osteoarthritis. Twenty participants with hip osteoarthritis (mean ± SD age: 58.7±15.3 years; body mass index: 28.8±4.2 kg/m2) and pain intensity on the Visual Analogue Scale ≥ 4 (8.05±1.2) were recruited to participate in this study. Pk and Af of hip flexors (seated position), abductors and adductors (supine position), and extensors (prone position) were collected in a single day by two independent raters, each one obtaining test and retest in randomly ordered separate sessions. The intra-rater intraclass correlation coefficient (ICC) was classified as good (>0.75) or excellent (≥0.90) for all muscle groups and all inter-rater ICCs were classified as excellent. Rater A had a lower standard error of measurement compared to rater B, ranging from 0.15 to 0.58 kilogram-force (Kgf) compared with 0.34 to 1.25 kg, respectively. However, the inter-rater comparison showed a minimal detectable change (MDC) of < 10% for all Pk and Af measures for hip adductors and extensors. Finally, the inter-rater Bland-Altman analysis demonstrated good agreement for abductors, adductors, and extensors. Despite pain and dysfunction related to hip osteoarthritis, the mean of two measures using a handheld dynamometer was shown to be a reliable tool to assess hip muscle strength, with good to excellent intra- and inter-rater ICCs, satisfactory agreement, and small values for MDC.

The Evidence for Pain in Hip Osteoarthritis and Symptom Production during the Stance Phase of Gait

The Evidence for Pain in Hip Osteoarthritis and Symptom Production during the Stance Phase of Gait

ACETABULAR SECTOR ANGLES IN ASYMPTOMATIC AND DYSPLASTIC HIPS: DEFINING THRESHOLDS FOR DYSPLASIA

Traditional radiographic criteria might underestimate or fail to detect subtle types of acetabular dysplasia. Acetabular sector angles (ASA) can measure the degree of anterior and posterior coverage of the femoral head on computed tomography (CT). This study aims to determine ASA values at different axial levels in a cohort of (1) asymptomatic, high-functioning hips without underlying hip pathology (controls); and (2) symptomatic, dysplastic hips that underwent periacetabular osteotomy (PAO). Thereby, we aimed to define CT-based thresholds for hip dysplasia and its subtypes.This is an IRB approved cross-sectional study of 51 high functioning, asymptomatic patients (102 hips) (Oxford Hip Score &gt;43), without signs of osteoarthritis (Tönnis grade≤1), who underwent a CT scan of the pelvis (mean age: 52.1±5.5 years; 52.9% females); and 66 patients (72 hips) with symptomatic hip dysplasia treated with peri-acetabular osteotomy (PAO) (mean age: 29.3±7.3 years; 85.9% females). Anterior and posterior acetabular sector angles (AASA &amp; PASA) were measured by two observers at three CT axial levels to determine equatorial, intermediate, and proximal ASA. Inter- and intra-observer reliability coefficient was high (between 0.882–0.992). Cut-off values for acetabular deficiency were determined based on Receiver Operating Characteristic (ROC) curve analysis, area under the curve (AUC) was calculated.The dysplastic group had significantly smaller ASAs compared to the Control Group, AUC was the highest at the proximal and intermediate PASA. Controls had a mean proximal PASA of 162°±17°, with a cut-off value for dysplasia of 137° (AUC: 0.908). At the intermediate level, the mean PASA of controls was 117°±11°, with a cut-off value of 107° (AUC 0.904). Cut-off for anterior dysplasia was 133° for proximal AASA (AUC 0.859) and 57° for equatorial AASA (AUC 0.868). Cut-off for posterior dysplasia was 102° for intermediate PASA (AUC 0.933).Measurement of ASA on CT is a reliable tool to identify dysplastic hips with high diagnostic accuracy. Posterior ASA less than 137° at the proximal level, and 107° at the intermediate level should alert clinicians of the presence of dysplasia.

WHICH FACTORS PREDICT A SUCCESSFUL OUTCOME FOLLOWING TOTAL HIP ARTHROPLASTY IN PATIENTS WITH EARLY RADIOLOGICAL OSTEOARTHRITIS?

It is unclear whether patients with early radiographic osteoarthritis (OA) but severe hip symptoms benefit from total hip replacement (THR). We aimed to assess which factors were associated with successful THR in this patient group.From a consecutive series of 1,935 patients undergoing THR we identified 70 (3.6%) patients with early OA (Kellgren and Lawrence (KL) grades 0-2). These were compared with 200 patients with advanced OA (KL grades 3–4). Outcomes were Oxford Hip Scores (OHS), EQ5D and EQ-VAS scores; compared pre-operatively with one year post-operatively. We investigated which clinical and radiographic (plain x-ray, CT, MRI) features predicted successful THR in the early OA group. Success was defined as reaching a postoperative OHS≥42.The early OA group were significantly younger (61 vs 66 years; P=0.0035). There were no significant differences in body mass index, ASA grade or gender. After adjusting for confounders, the advanced OA group had a significantly greater percentage of possible change (PoPC) in OHS (75.8% versus 50.4%; P&lt;0.0001) and improvement in EQ5D (0.151 versus 0.002; P&lt;0.0001). There were no significant differences in complication, revision or readmission rates. In the early OA group, we identified 16/70 (22.9%) patients who had a ‘successful’ THR. Of those with early OA, 38 patients had pre-operative CT or MRI scans. Patients who had a ‘successful’ THR were significantly more likely to have subchondral cysts on CT/MRI (91.7% versus 57.7%; P=0.0362). The presence of cysts on CT/MRI was associated with a significantly greater PoPC in OHS (61.6% versus 38.2%; P=0.0353). The combination of cysts and joint space width (JSW) &lt;1mm was associated with a PoPC of 68%. Plain radiographs were found to significantly underestimate the narrowest JSW compared to CT/MRI (2.4mm versus 1.0mm; P&lt;0.0001).We advise caution in performing THRs in patients with early OA (KL grades 0-2) on plain radiographs. We advocate pre-operative cross-sectional imaging (CT or MRI) in these patients. In the absence of cysts on cross-sectional imaging, a THR seems unlikely to provide a satisfactory outcome.

The Association between Oxytocin and Lower Limb Osteoarthritis: A Prospective Cohort Study

Oxytocin (OT), a neuropeptide best known for its role in emotional and social behaviors, has been linked to osteoarthritis (OA). This study aimed to investigate the serum OT level in hip and/or knee OA patients and to study its association with disease progression. Patients from the KHOALA cohort with symptomatic hip and/or knee OA (Kellgren and Lawrence (KL) scores of 2 and 3) and follow-up at 5 years were included in this analysis. The primary endpoint was structural radiological progression, which was defined as an increase of at least one KL point at 5 years. Logistic regression models were used to estimate the associations between OT levels and KL progression while controlling for gender, age, BMI, diabetes and leptin levels. Data from 174 hip OA patients and 332 knee OA patients were analyzed independently. No differences in OT levels were found between the ‘progressors’ and ‘non-progressors’ groups among the hip OA patients and knee OA patients, respectively. No statistically significant associations were found between the OT levels at baseline and KL progression at 5 years, the KL score at baseline or the clinical outcomes. Higher structural damage at baseline and severe structural progression of hip and knee osteoarthritis did not appear to be associated with a low serum OT level at baseline.