Anterior Cruciate Ligament Repair With Suture Tape Augmentation of Proximal Tears and Early Anterior Cruciate Ligament Reconstruction With Suture Tape Augmentation Result in Comparable Clinical Outcomes With Anterior Cruciate Ligament Reconstruction at 2-Year Follow-Up.

PURPOSE: To compare the postoperative side-to-side laxity and short-term clinical outcomes of patients who received primary anterior cruciate ligament (ACL) repair with suture tape augmentation, acute anterior cruciate ligament reconstruction (ACLR) with suture tape augmentation performed within 8 weeks of injury (ACLRacute), or ACLR beyond 8 weeks of injury. METHODS: After institutional review board approval was obtained, 100 patients were enrolled in this prospective trial: 34 primary ACL repair with suture tape augmentation, 33 ACLRs performed within 8 weeks of injury (ACLRacute), and 33 ACLRs. Patients were allocated to ACL repair if a proximal avulsion was present with good tissue quality (Sherman type 1), confirmed by intraoperative diagnostic arthroscopy. Preoperative side-to-side anteroposterior knee laxity was assessed with KT-1000 arthrometer, and patient-reported outcomes (PROs) including the visual analog scale, Marx activity scale, Veterans RAND 12-item health survey (VR-12 physical & mental), Single Assessment Numeric Evaluation, Knee Injury and Osteoarthritis Outcome Score survey subscales, and range of motion were collected. These objective and subjective measures were repeated at regular intervals postoperatively through 2 years. Minimal clinically important difference calculations were performed assessing postoperative PRO changes at 2 years compared with preoperative. RESULTS: The average time from injury to surgery was 5.03 ± 1.2 weeks for the ACL repair group, 5.09 ± 0.74 weeks for the ACLRacute, and 43.22 ± 33.5 weeks for the ACLR group. Postoperatively, the KT-1000 side-to-side laxity difference for 30 lbs was determined to be 0.1 ± 0.37 (95% confidence interval [CI] -0.7 to 0.8) for ACL repair versus ACLR (P < .0001), -0.8 ± 0.35 (95% CI -1.5 to -0.1) for ACLRacute versus ACLR (P < .0001), and 0.8 ± 0.40 (95% CI 0.0-1.6) for ACL repair versus ACLRacute (P < .0001). The data reveal ACL repair and ACLRacute are noninferior to ACLR at 2-year follow-up. The postoperative difference from baseline for all PROs demonstrated improvement for all PROs. Magnetic resonance imaging at 1 year revealed tissue healing for the 3 ACL injury treatment groups. CONCLUSIONS: Patients who underwent ACL repair of proximal tears with suture tape augmentation or ACL reconstruction within 8 weeks from injury resulted in noninferior side-to-side knee laxity, comparable PROs, and similar range of motion at 2-year follow-up compared with ACLR. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Native anterior talo-fibular ligament tensile characteristics compared to allograft, suture tape, and copolymer augmentation elements: A biomechanical study.

Surgical augmentation methods have been introduced to the Modified Broström (MB) technique to support native anterior talo-fibular ligament (ATFL) healing and function. This study aimed to investigate the isolated biomechanical performance of common MB augmentation elements, including allograft, suture tape, and copolymer, compared to native ATFL. Six cadaveric feet were dissected, isolating the ATFL from all surrounding soft tissue. The fibula and talus were clamped on the testing frame so that the ligament was in line with the load cell. Six samples per augment group were fixed on a test frame with a gauge length of 20 mm to replicate ATFL length. All samples were pulled to failure at 305 mm/min. Biomechanical outcomes included stiffness, elongation, and ultimate load. Mean ± standard deviation was reported. Stiffness was highest for suture tape (246.4 ± 52.1N/mm), followed by allograft (114.2 ± 26.2 N/mm), native ATFL (78.6 ± 31.8 N/mm), and copolymer (9.4 ± 2.9 N/mm). Significant differences in stiffness were observed between all groups except when comparing ATFL stiffness to allograft (P = 0.086). Copolymer resulted in significantly larger elongation at ultimate load compared to native ATFL, suture tape, and allograft (P < 0.001). Elongation at ultimate failure was highest for copolymer (30.0 ± 8.7 mm) and significantly greater than all other groups (P < 0.001). Ultimate load was highest for suture tape (544.1 ± 59.7 N), followed by native ATFL (338.5 ± 63.7 N), allograft (308.3 ± 98.5 N) and copolymer (146.7 ± 8.9 N). Suture tape ultimate load was significantly greater than copolymer (P < 0.001). Isolated biomechanical data of augment materials can be utilized by foot and ankle surgeons when considering appropriate ligament augmentation options. Level of clinical evidence 5, controlled laboratory study.

Accuracy of 3 Clinical Tests to Diagnose Proximal Hamstrings Tears With and Without Sciatic Nerve Involvement in Patients With Posterior Hip Pain.

PURPOSE: To determine the diagnostic accuracy of the active hamstring test at 30° (A-30) and 90° (A-90) of knee flexion, the long stride heel strike (LSHS) test, and combination of the 3 tests for individuals with hamstring tendon tears, with and without sciatic nerve involvement. METHODS: A retrospective review of 564 consecutive clinical records identified 42 subjects with a mean age of 50.31 ± 15 years who underwent a standard physical examination prior to magnetic resonance imaging (MRI) evaluation and diagnostic injection for posterior hip. The physical examination included the A-30, A-90, and LSHS tests. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were calculated to determine the diagnostic accuracy of these 3 tests. RESULTS: Forty-two subjects (female = 32 and male = 10) with a mean age of 50.31 years (range 15-77, ± SD 14.52) met the inclusion criteria and were included in the review. Based on MRI and/or injection, 64.28% (27/42) of subjects were diagnosed with hamstring tear. Fourteen (51.85%) presented with sciatic nerve involvement. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for each test were as follows: A-30 knee flexion: 0.73, 0.97, 23.43, 0.28, and 84.73; A-90 knee flexion: 0.62, 0.97, 20.00, 0.39, and 51.67; LSHS: 0.55, 0.73, 2.08, 0.61, and 3.44. The most accurate findings were obtained when the results of the A-30 and A-90 were combined, with sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of 0.84, 0.97, 26.86, 0.17, and 161.89, respectively. CONCLUSION: The combination of the active hamstring A-30 and A-90 tests proved to be a highly accurate and valuable tool to diagnose proximal hamstring tendons tears with or without sciatic nerve involvement in subjects presenting with posterior hip pain. LEVEL OF EVIDENCE: Level III, diagnostic study.

Contribution of the Pubofemoral Ligament to Hip Stability: A Biomechanical Study.

PURPOSE: To determine the isolated function of the pubofemoral ligament of the hip capsule and its contribution to hip stability in external/internal rotational motion during flexion greater than 30° and abduction. METHODS: Thirteen hips from 7 fresh-frozen pelvis-to-toe cadavers were skeletonized from the lumbar spine to the distal femur with the capsular ligaments intact. Computed tomographic imaging was performed to ensure no occult pathological state existed, and assess bony anatomy. Specimens were placed on a surgical table in supine position with lower extremities resting on a custom-designed polyvinylchloride frame. Hip internal and external rotation was measured with the hip placed into a combination of the following motions: 30°, 60°, 110° hip flexion and 0°, 20°, 40° abduction. Testing positions were randomized. The pubofemoral ligament was released and measurements were repeated, followed by releasing the ligamentum teres. RESULTS: Analysis of the 2,106 measurements recorded demonstrates the pubofemoral ligament as a main controller of hip internal rotation during hip flexion beyond 30° and abduction. Hip internal rotation was increased up to 438.9% (P < .001) when the pubofemoral ligament was released and 412.9% (P < .001) when both the pubofemoral and teres ligament were released, compared with the native state. CONCLUSIONS: The hypothesis of the pubofemoral ligament as one of the contributing factors of anterior inferior hip stability by controlling external rotation of the hip in flexion beyond 30° and abduction was disproved. The pubofemoral ligament maintains a key function in limiting internal rotation in the position of increasing hip flexion beyond 30° and abduction. This cadaveric study concludes previous attempts at understanding the anatomical and biomechanical function of the capsular ligaments and their role in hip stability. CLINICAL RELEVANCE: The present study contributes to the understanding of hip stability and biomechanical function of the pubofemoral ligament.

Commercial suture passer improves efficiency and ease of use versus conventional needle in minimally invasive thoracolumbar fascia closure: a cadaveric analysis.

Background: Low-profile suture passers have been introduced to facilitate thoracolumbar fascia closure in minimally invasive spine (MIS) surgery. The purpose of this study was to evaluate the closure time of a modern suture passer to a conventional curved need for MIS fascia closure in a cadaveric model. Methods: Six clinicians specializing in orthopedic spine surgery were recruited for the study and randomly assigned 1 cadaveric torso. Subcutaneous tissue was resected at L4-L5, replicating MIS surgery, followed by placement of a 60×18-mm or 100×18-mm tubular retractor for access. Clinicians were required to close the fascia with three unknotted, simple interrupted sutures using a swaged curved needle or suture passer (Spine Scorpion™, Arthrex, Inc., Naples, FL). The completion time was recorded, starting immediately before suturing and ending after the last pass. A time cutoff of 10 min was implemented in consideration of reasonable operating room time, and the number of achieved suture passes (of 6) were recorded. Clinicians were asked to qualitatively grade ease of use in relation to prior fascial closure experience per a 0-5 scale, where 0 is impossible and 5 is easiest. Results: The mean change in fascial closure completion time (Δ) was significantly reduced with the Spine Scorpion compared to the curved needle with the 60×18-mm retractor (Δ=5.80 min; 95% CI, 2.92-8.67 min; p=.004) and 100 × 18-mm retractor (Δ=5.28 min; 95% CI, 2.76-7.80 min; p=.003). Full closure was achieved within the time limit for all trials of the Spine Scorpion, while the standard needle achieved full closure in 67% (4 of 6) and 50% (3 of 6) of trials with the 60 × 18-mm and 100×18-mm retractors, respectively. Median ease-of-use scores with the 60×18-mm and 100×18-mm retractors, respectively, were 4.5 (range, 4-5) and 4.5 (range, 3-5) for the Spine Scorpion, and both 1.0 (range, 1-2) for the curved needle. Conclusion: Results from this laboratory investigation using a suture passer for thoracolumbar fascia closure show a significant reduction in closure time and completion of the procedure compared to a conventional curved needle.

Sagittal Pelvic Tilt Directly Influences the Ischiofemoral Space: A Cadaveric Study.

BACKGROUND: Ischiofemoral impingement (IFI) is understood to be a pain generator in the deep gluteal space. Femoral position is known to influence the ischiofemoral space (IFS), but there has been no study examining the effect of sagittal pelvic tilt on the IFS. The purpose of this study was to determine whether changes in pelvic tilt in the sagittal plane lead to changes in the dimensions of the IFS. MATERIALS AND METHODS: Five fresh frozen cadavers (10 hips) were used for this anatomic study. The specimens were skeletonized and placed in the prone position with the pelvis fixed to a custom-built hinged table. A digital inclinometer was used to tilt the pelvis -10°, 0°, and 10° simulating posterior, neutral, and anterior pelvic tilt, respectively. Digital calipers were used to measure the dimensions of the IFS in all three positions of sagittal pelvic tilt. RESULTS: Changes in pelvic tilt resulted in significant changes in the dimensions of the IFS. Mean IFS dimensions measured 29.3±9.7 mm, 37.2±9.0 mm, and 24.3±9.2 mm in the neutral, anterior, and posterior pelvic tilt positions, respectively (P<.0001). CONCLUSION: Changes in sagittal pelvic tilt influence the dimensions of the IFS, with posterior pelvic tilt noted to significantly decrease the IFS when compared with neutral and anterior pelvic tilt. These findings suggest that further evaluation of sagittal spinopelvic balance in the etiology of symptomatic IFI may be warranted. [Orthopedics. 2024;47(3):167-171.].

Circumferential Labral Reconstruction With Knotless All-Suture Anchors Restores Hip Distractive Stability: A Cadaveric Biomechanical Analysis.

BACKGROUND: The essential component of managing femoroacetabular impingement involves restoration of the original labral function. Circumferential labral reconstruction (CLR) has shown positive results. However, biomechanical studies of CLR are limited and have not established the efficacy of the modern knotless all-suture anchor (ASA) pull-through technique. HYPOTHESES: (1) CLR with knotless ASA fixation will restore native labral suction seal biomechanics; (2) tensioning the ASA to a high-tension state will increase the peak distractive force. STUDY DESIGN: Controlled laboratory study. METHODS: Eight fresh-frozen human cadaveric hips were dissected free of all soft tissue except the native labrum and transverse acetabular ligament. On an electromechanical testing system, the hips were compressively loaded to 250 N to initiate a suction seal and distracted at a rate of 10 mm/s until rupture of the suction seal. Hips were tested in 4 states: intact labrum, full labral removal, knotless CLR with moderate anchor tension, and CLR with high anchor tension. Peak distractive force (in newtons) was compared using repeated measures analysis of variance (P < .05). Acetabular bevel angles (θ) were measured at labral clockface positions outside the transverse acetabular ligament using a 3-dimensional digitizer stylus after rim preparation. Linear regression plots compared θ and peak distractive force in the CLR state. RESULTS: Peak force values were 138.5 ± 13.6 N (mean ± SE) for the intact labrum, 18.4 ± 2.79 N for labral excision, 95.4 ± 23.3 N for moderate-tension CLR, and 126.2 ± 27.3 N for high-tension CLR. Significant differences were observed only when full labral removal was compared with the other conditions: intact (P < .001), moderate-tension CLR (P = .016), and high-tension CLR (P = .002). Steeper acetabular bevel angles (smaller θ) were correlated with greater suction seal restoration (P < .05). CONCLUSION: CLR restored distractive stability on average to 82.0% of the intact value after labral deficiency. Retensioning did not significantly increase peak distractive forces. CLINICAL RELEVANCE: These findings provide biomechanical validation supporting CLR using knotless ASAs in an effort to minimize volumetric bone loss and provide other surgical advantages. The prepared rim's bevel angle may be an important variable to optimize for improved suction seal restoration.

Cumulative group metrics: a new and efficient method to measure the scientific impact of research groups.

Various metrics have emerged for assessing scientific impact, most of which are based on complex calculations and, in many cases, are not freely available. Moreover, most of these metrics are not intended for assessing the scientific impact of research groups. Cumulative group metrics are proposed as an efficient and cost-effective strategy for measuring group scientific impact. Materials and methods: The authors collected peer-reviewed output in 2020 from two academic orthopedic surgery departments [University of Michigan (UM) and Mayo Clinic Rochester (MC)] and one medical device research department [Arthrex Inc. (AI)]. The sites evaluated the Cumulative Group Number of Publications (CGNP), Cumulative Journal Impact Factor (CJIF), Cumulative CiteScore (CCS), Cumulative SCImago Journal Rank (CSJR), and Cumulative Source Normalized Impact per Paper (CSNIP) for the three institutions. Results: In 2020, UM published 159 peer-reviewed studies, MC published 347 peer-reviewed studies, and AI supported 141 publications. The UM publications achieved a CJIF of 513, a CCS of 891, a CSJR of 255, and a CSNIP of 247. The MC publications achieved a CJIF of 956, a CCS of 1568, a CSJR of 485, and a CSNIP of 508. AI-supported publications achieved a CJIF of 314, a CCS of 598, a CSJR of 189, and a CSNIP of 189. Conclusion: The presented cumulative group metrics are an effective tool to assess the scientific impact of a research group. The cumulative submetrics can further evaluate research groups compared with other departments due to field normalization. Department leadership and funding agencies can utilize these metrics to evaluate research output quantitatively and qualitatively.

Bipolar Radiofrequency Ablation Does Not Result in Full-Thickness Articular Cartilage Penetration: An Ex Vivo Bovine Investigation.

Purpose: To evaluate the depth of penetration of manufacturer-recommended bipolar radiofrequency (BRF) output in healthy hyaline cartilage. Methods: Two matched knees from a bovine specimen were harvested for immediate testing. BRF probes were used to treat the articular cartilage in a hydrated noncontact technique employing a 1-mm spacer on patellar, condylar, and trochlear surfaces. Two manufacturer-recommended ablate power settings were evaluated to analyze the effect of varying power outputs on the depth of penetration. Surfaces were randomized and treated with BRF ablate setting 3 (AB-3), 4 (AB-4), or left untreated as a control (12 grids each). Slices were extracted from treatment zones and subjected to fluorescein diacetate and propidium iodide viability stains and analyzed with confocal light microscopy. A general linear model was used to determine whether variables such as ablation setting, cartilage location, and side significantly influenced depth of penetration (DoP) and cartilage thickness (Minitab 19, Chicago, IL). When significance was noted (P < .05), a post hoc-Tukey test was used to investigate specific differences. Results: AB-3 had a 50.9% lower mean DoP than AB-4 (P = .006). The mean DoP was 237.9 ± 140.6 µm for AB-3 and 484.1 ± 267.0 µm for AB-4. Median DoP values were 243.2 ± 149.5 µm for AB-3, 51.2% lower than the 498.4 ± 286.0 µm for AB-4. The mean maximum DoP for AB-3 was 302.4 ± 167.8 µm, 50.6% lower than AB-4 value of 611.6 ± 299.1 µm. Analysis of the cartilage thickness confirmed there was no difference in overall cartilage thickness used for AB-3 versus AB-4 testing (P = .953). Conclusions: The RF probe ablate power setting AB-3 demonstrated significantly less articular cartilage depth of penetration than the AB-4 setting in a healthy bovine model. Clinical Relevance: Debridement of chondral lesions with plasma BRF is of clinical interest. The presented study adds basic science information for those considering performing this technique.

Biomechanical Analysis of Single Interference Screw vs Interference Screw With Cortical Button for Flexor Hallucis Longus Transfer.

BACKGROUND: Flexor hallucis longus tendon transfer (FHL) with a cortical button tension slide is an innovative addition that has not been measured against traditional methods. METHODS: 12 pairs (n=24) of fresh-frozen cadaveric tibia-to-toe samples were used and randomized to receive one of the operative FHL techniques. Specimens underwent bone density analysis. Biomechanical loading was applied between 20 and 60 N at 1 Hz for 100 cycles. Post-cyclic load to failure occurred at 1.25 mm/s. Cyclic displacement, structural stiffness, and ultimate load were derived from load-displacement curves. Student t tests evaluated significant effects between both FHL techniques. Linear regression analysis assessed interactions between bone density and strength of FHL technique. RESULTS: Average tendon diameter was 5.44±0.46 mm. Average bone density was 1.06±0.08 g/cm2. Addition of a cortical button to FHL transfer did not significantly affect cyclic displacement (0.78±0.52 mm vs 0.87±0.80 mm) or structural stiffness (162.11±43.34 N/mm vs 167.57±49.19 N/mm). Cortical button addition to FHL transfer resulted in significantly increased ultimate load (343.72±68.93 N) compared with interference screw alone (255.62±77.17 N) (P = .0002). Linear regression analyses did not reveal any significant interactions between bone density and FHL tendon transfer technique. CONCLUSION: Enhanced strength can be achieved with FHL tendon transfer to calcaneus using an interference screw and cortical button tension slide technique as compared to an interference screw alone. Cortical buttons in the setting of FHL tendon transfer to the calcaneus offers an additional level of support. CLINICAL RELEVANCE: Operative cases presenting with poor bone quality due to osteoporosis or osteopenia could benefit from cortical button fixation during FHL transfer. Clinical studies are needed to determine if the increased construct stability conferred from the additional use of a flip button results in fewer FHL transfer failures or better clinical outcomes. LEVEL OF EVIDENCE: Level V, Controlled Laboratory Study.

Hip-spine syndrome: rationale for ischiofemoral impingement, femoroacetabular impingement and abnormal femoral torsion leading to low back pain.

The term 'hip-spine syndrome' was introduced in recognition of the frequent occurrence of concomitant symptoms at the hip and lumbar spine. Limitations in hip range of motion can result in abnormal lumbopelvic mechanics. Ischiofemoral impingement, femoroacetabular impingement and abnormal femoral torsion are increasingly linked to abnormal hip and spinopelvic biomechanics. The purpose of this narrative review is to explain the mechanism by which these three abnormal hip pathologies contribute to increased low back pain in patients without hip osteoarthritis. This paper presents a thorough rationale of the anatomical and biomechanical characteristics of the aforementioned hip pathologies, and how each contributes to premature coupling and limited hip flexion/extension. The future of hip and spine conservative and surgical management requires the implementation of a global hip-spine-pelvis-core approach to improve patient function and satisfaction.

Carbon dioxide gas endoscopy of the deep gluteal space.

The treatment of hip and pelvic pain associated with abnormalities of the deep gluteal space has evolved and increasingly involves endoscopic techniques with a saline expansion medium. This investigation presents a surgical technique utilizing carbon dioxide as the insufflation medium for deep gluteal space endoscopy in 17 cadaveric hips. This technique was successful in 94% (16/17) of the hips, allowing for visualization of the sciatic nerve, posterior femoral cutaneous nerve, pudendal nerve, branch of the inferior gluteal artery crossing the sciatic nerve, piriformis muscle, hamstring tendon origin, and lesser trochanter. Our experience suggests that gas expansion presents several advantages over fluid expansion.

Anteroinferior Hip Instability in Flexion During Dynamic Arthroscopic Examination Is Associated With Abnormal Anterior Acetabular Horn.

BACKGROUND: The stabilization of the femoral head is provided by the distal acetabulum when the hip is in a flexed position. However, the osseous parameters for the diagnosis of hip instability in flexion are not defined. PURPOSE/HYPOTHESIS: To determine whether the osseous parameters of the distal acetabulum are different in hips demonstrating anteroinferior subluxation in flexion under dynamic arthroscopic examination, compared with individuals without hip symptoms. The hypothesis was that the morphometric parameters of the anterior acetabular horn are distinct in hips with anteroinferior instability compared with asymptomatic hips. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 30 hips with anteroinferior instability in flexion under dynamic arthroscopic examination were identified. A control group of 60 hips (30 patients), matched by age and sex, was formed from individuals who had undergone pelvis magnetic resonance imaging (MRI) for nonorthopaedic reasons. Unstable and control hips were compared according to the following parameters assessed on axial MRI scans of the pelvis: anterior sector angle (ASA), anterior horn angle (AHA), posterior sector angle (PSA), posterior horn angle (PHA), acetabular version, lateral center-edge angle, acetabular inclination (Tönnis angle), and femoral head diameter. RESULTS: The coverage of the femoral head by the anterior acetabular horn was decreased in unstable hips compared with the control group (mean ASA, 54.8° vs 61°, respectively; P < .001). Unstable hips also had a steeper anterior acetabular horn, with an increased mean AHA compared with controls (52.5° vs 46.8°, respectively; P < .001). An ASA <58° had a sensitivity of 0.8, a specificity of 0.68, a negative predictive value of 0.87, and a positive predictive value of 0.56 for anteroinferior hip instability. An AHA >50° had a sensitivity of 0.77, a specificity of 0.72, a negative predictive value of 0.86, and a positive predictive value of 0.57 for anteroinferior hip instability. There was no statistically significant difference in the mean PSA, PHA, acetabular version, lateral center-edge angle, acetabular inclination, or femoral head diameter between unstable hips and controls. CONCLUSION: Abnormal morphology of the anterior acetabular horn is associated with anteroinferior instability in hip flexion. The ASA and AHA can aid in the diagnosis of hip instability.

Bioinformatics analysis integrating metabolomics of m6A RNA microarray in intervertebral disc degeneration.

Aim: To explore the potential functions and mechanism of N6.methyladenosine (m6A) abnormality of RNAs in nucleus pulposus from the intervertebral disc degeneration (IDD). Materials & methods: We performed rat model, m6A epitranscriptomic microarray, bioinformatics analysis and metabolomics. Results: In IDD, most of the differentially methylated RNAs showed a significant demethylation situation. The competing endogenous RNA network LOC102555094/miR-431/GSK-3ß combining downstream Wnt pathway were identified in bioinformatics analysis. For metabolomics, activation of Wnt pathway led to reprogramming of glucose metabolism and enzyme activation of PKM2. Finally, quantitative real-time PCR and methylated RNA immunoprecipitation coupled with quantitative real-time PCR revealed the positive correlation between demethylation of LOC102555094 and expression of both FTO and ZFP217. Conclusion:LOC102555094 might be demethylated by ZFP217, activating FTO and LOC102555094/miR-431/GSK-3ß/Wnt played a crucial role in IDD.

Proximal iliotibial band thickness as a cause for recalcitrant greater trochanteric pain syndrome.

To investigate iliotibial band (ITB) diameter thickness at the greater trochanter in patients requiring iliotibial band release who have failed conservative modalities, in comparison to an asymptomatic patient population. A total of 68 subjects were selected to be reviewed using T2 axial plane MRI. The ITB diameter thickness was measured in 34 subjects who underwent surgical ITB release, and compared with a match-paired asymptomatic hip cohort consisting of 34 subjects. ITB diameter thickness was measured at the thickest location for each subject twice by two different examiners. Inter/intra class correlation coefficient was determined for ITB measurement technique accuracy, and the presence of recalcitrant proximal hip pain was evaluated. Interclass correlation coefficient with 95% confidence was measured to be 0.953. The average thickness for ITB surgical release subjects was measured to be 5.61 ± 2.10 mm, and for asymptomatic subjects 3.77 ± 0.79 mm (P < 0.001). The results of this study demonstrate a statistically significant positive relationship of an increased diameter thickness in the ITB in symptomatic patients who failed conservative therapy and underwent surgical intervention for treatment.

The effects of hip abduction on sciatic nerve biomechanics during terminal hip flexion.

Terminal hip flexion contributes to increased strain in peripheral nerves at the level of the hip joint. The effects of hip abduction and femoral version on sciatic nerve biomechanics are not well understood. A decrease in sciatic nerve strain will be observed during terminal hip flexion and hip abduction, independent of femoral version. Six un-embalmed human cadavers were utilized. Three Differential Variable Reluctance Transducers (DVRTs) sensors were placed on the sciatic nerve while the leg was flexed to 70° with a combination of - 10°, 0°, 20° and 40° adduction/abduction. DVRT placement included: (i) under piriformis, (ii) immediately distal to the gemelli/obturator, (iii) four centimeters distal to sensor two. A de-rotational osteotomy to decrease femoral version 10° was performed, and sciatic nerve strain was measured by the same procedure. Data were analyzed with three-way analysis of variance and Bonferroni post-hoc analysis to identify differences in the mean values of sciatic nerve strain between native and decreased version state, hip abduction angle and DVRT sensor location. Significant main effects were observed for femoral version (P = 0.04) and DVRT sensor location (P = 0.01). Sciatic nerve strain decreased during terminal hip flexion and abduction in the decreased version state. An 84.23% decrease in sciatic nerve strain was observed during hip abduction from neutral to 40° in the presence of decreased version at terminal hip flexion. The results obtained from this study confirm the role of decreased femoral version and hip abduction at terminal hip flexion to decrease the strain in the sciatic nerve.