The Hip-Spine Effect: A Biomechanical Study of Ischiofemoral Impingement Effect on Lumbar Facet Joints.

PURPOSE: To assess the relation between ischiofemoral impingement (IFI) and lumbar facet joint load during hip extension in cadavers. METHODS: Twelve hips in 6 fresh T1-to-toes cadaveric specimens were tested. A complete pretesting imaging evaluation was performed using computed tomography scan. Cadavers were positioned in lateral decubitus and fixed to a dissection table. Both legs were placed on a frame in a simulated walking position. Through a posterior lumbar spine approach L3-4 and L4-5 facet joints were dissected bilaterally. In addition, through a posterolateral approach to the hip, the space between the ischium and the lesser trochanter was dissected and measured. Ultrasensitive, and previously validated, piezoresistive force sensors were placed in lumbar facet joints of L3-4 and L4-5. Lumbar facet loads during hip extension were measured in native hip conditions and after simulating IFI by performing lesser trochanter osteotomy and lengthening. Four paired t-tests were performed comparing normal and simulated IFI on the L3-L4 and L4-L5 facet joint loads. RESULTS: After simulating IFI, mean absolute differences of facet joint load were 10.8 N (standard error of the mean [SEM] ±4.53, P = .036) for L3-4 at 10° of hip extension, 13.71 N (SEM ±4.53, P = .012) for L3-4 at 20° of hip extension, 11.49 N (SEM ±4.33, P = .024) for L4-5 at 10° of hip extension, and 6.67 N (SEM ±5.43, P = .245) for L4-5 at 20° of hip extension. A statistically significant increase in L3-4 and L4-5 lumbar facet joint loads of 30.81% was found in the IFI state as compared with the native state during terminal hip extension. CONCLUSIONS: Limited terminal hip extension due to simulated IFI significantly increases L3-4 and L4-5 lumbar facet joint load when compared with non-IFI native hips. CLINICAL RELEVANCE: This biomechanical study directly links IFI to increased lumbar facet loads and supports the clinical findings of IFI causing lumbar pathology. Assessing and treating (open or endoscopic) hip disorders that limit extension could have benefit in patients with concomitant lower back symptoms.

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.

Surgical Management of Deep Gluteal Syndrome Causing Sciatic Nerve Entrapment: A Systematic Review.

PURPOSE: To assess the causes, surgical indications, patient-reported clinical outcomes, and complications in patients with deep gluteal syndrome causing sciatic nerve entrapment. METHODS: Three databases (PubMed, Ovid [MEDLINE], and Embase) were searched by 2 reviewers independently from database inception until September 7, 2016. The inclusion criteria were studies reporting on both arthroscopic and open surgery and those with Level I to IV evidence. Systematic reviews, conference abstracts, book chapters, and technical reports with no outcome data were excluded. The methodologic quality of the studies was assessed with the MINORS (Methodological Index for Non-randomized Studies) tool. RESULTS: The search identified 1,539 studies, of which 28 (481 patients; mean age, 48 years) were included for assessment. Of the studies, 24 were graded as Level IV, 3 as Level III, and 1 as Level II. The most commonly identified causes were iatrogenic (30%), piriformis syndrome (26%), trauma (15%), and non-piriformis (hamstring, obturator internus) muscle pathology (14%). The decision to pursue surgical management was made based on clinical findings and diagnostic investigations alone in 50% of studies, whereas surgical release was attempted only after failed conservative management in the other 50%. Outcomes were positive, with an improvement in pain at final follow-up (mean, 23 months) reported in all 28 studies. The incidence of complications from these procedures was low: Fewer than 1% and 8% of open surgical procedures and 0% and fewer than 1% of endoscopic procedures resulted in major (deep wound infection) and minor complications, respectively. CONCLUSIONS: Although most of the studies identified were case series and reports, the results consistently showed improvement in pain and a low incidence of complications, particularly for endoscopic procedures. These findings lend credence to surgical management as a viable option for buttock pain caused by deep gluteal syndrome and warrant further investigation. LEVEL OF EVIDENCE: Level IV, systematic review of Level II through IV studies.

Influence of Aging on Microvascular Supply of the Gluteus Medius Tendon: A Cadaveric and Histologic Study.

PURPOSE: The purpose of this cadaveric study was to assess the relation between age and microvascular supply of 3 areas of the gluteus medius tendon using a previously validated CD31 immunohistochemistry staining technique. METHODS: Twenty-four fresh-frozen gluteus medius specimens were obtained through a posterolateral approach to the hip. Specimens aged 18 years or older, of either sex, and of any race were considered for this study. The average age of donors was 47.3 years (range, 18-68 years). Each sample was divided into 3 portions: musculotendinous, tendinous, and tendon-bone junction. H&E staining was used for qualitative structural analysis, and then all samples underwent staining with CD31 immunohistochemistry for quantitative assessment of vessels per square millimeter. A comparison of the microvessel density between zones according to age was performed by an analysis of variance. To evaluate the relation between microvessel supply and age, a regression model with curvilinear estimation was used. The data were fitted to a quadratic model. RESULTS: Vascular supply in transversal and longitudinal cuts regardless of the zone was, on average, 53.9 ± 32.1 vessels/mm2 and 51.1 ± 19.3 vessels/mm2, respectively. All the areas of the tendon showed a strength of relation (R) ranging from 0.41 to 0.76 between age and vascular supply. In addition, the proportion of vascular supply change explained by age (R2) was significant in most cases (ranging from 0.17 to 0.56, with P < .05). CONCLUSIONS: There is a chronological relation between aging and microvascular supply of the gluteus medius tendon, in which an initial increase occurs from 18 years of age to 30 to 40 years of age, with a progressive decrease after 50 years of age. CLINICAL RELEVANCE: The findings of our study may have implications for increased vulnerability of the gluteus medius tendon and decreased healing potential.

Ischiofemoral impingement: defining the lesser trochanter-ischial space.

PURPOSE: The purpose of this study was to define changes in the ischial-lesser trochanteric space associated with medial and lateral hip rotation in neutral and 10° of extension and adduction. METHODS: Twenty-five hip joints from 14 embalmed cadavers (7 males and 7 females) were used for this study. The pelvic region of each cadaver was skeletonized, and the hip capsule released distally. With the hip joint in 0° flexion-extension/abduction-adduction, the distance between the lesser trochanter and ischium was measured in: neutral rotation, 40° medial rotation, and 60° lateral rotation. A one-way ANOVA with post hoc analysis determined the difference in the ischiofemoral space in these three positions. An additional position was then tested by laterally rotating the femur with the hip joint positioned in 10° extension and adduction. RESULTS: The average distance between the lesser trochanter and ischium was different (p < .0005) in neutral rotation, 40° medial rotation, and 60° lateral rotation at 2.8 cm (SD 1.1), 4.3 cm (SD 1.2), and 1.4 cm (SD 0.7), respectively. With the hip joint laterally rotated from a starting position of 10° extension and adduction, 21 of 25 (84 %) hips made contact between the lesser trochanter and ischium at an average position of 29° (SD 20) of lateral rotation. CONCLUSIONS: The lesser trochanter is closest to the ischium in lateral rotation and is furthest away in medial rotation when the hip is in neutral flexion-extension/abduction-adduction. The lesser trochanter approximates the ischium when the hip is laterally rotated in 10° extension and adduction. The information gained through this investigation helps to define the pathomechanics associated with ischiofemoral impingement and validate clinical tests to diagnose ischiofemoral impingement.

Capsulotomy Size Affects Hip Joint Kinematic Stability.

PURPOSE: To evaluate the effect of capsulotomy size and subsequent repair on the biomechanical stability of hip joint kinematics through external rotation of a cadaveric hip in neutral flexion. METHODS: Eight fresh-frozen cadaveric hip specimens were used in this study. Each hip was tested under torsional loads of 6 N·m applied by a servohydraulic frame and transmitted by a pulley system. The test conditions were (1) neutral flexion with the capsule intact, (2) neutral flexion with a 4-cm interportal capsulotomy, (3) neutral flexion with a 6-cm capsulotomy, and (4) neutral flexion with capsulotomy repair. Soft tissue was retained during all interventions. Measures indicating joint kinematics (range of motion [ROM], hysteresis area [HA], and neutral zone [NZ]) were obtained for each condition. RESULTS: For all hip specimens, the average ROM, HA, and NZ were calculated relative to the intact capsular state (100%) and expressed in terms of percentage (± SD). The findings for ROM were as follows: intact, 100%; 4 cm, 107.42% ± 5.69%; 6 cm, 113.40% ± 7.92%; and repair, 99.78% ± 3.77%. The findings for HA were as follows: intact, 100%; 4 cm, 108.30% ± 9.30%; 6 cm, 115.30% ± 13.92%; and repair, 99.47% ± 4.12%. The findings for NZ were as follows: intact, 100%; 4 cm, 139.61% ± 62.35%; 6 cm, 169.25% ± 78.19%; and repair, 132.03% ± 64.38%. Statistically significant differences in ROM existed between the intact and 4-cm conditions (P = .039), the intact and 6-cm conditions (P < .0001), the 4-cm and repair conditions (P = .033), and the 6-cm and repair conditions (P < .0001). There was no statistically significant difference between the intact and repair conditions (P > .99) or between the 4- and 6-cm conditions (P = .126). CONCLUSIONS: Under laboratory-based conditions, larger-sized capsulotomies were accompanied by increases in all 3 measures of joint mobility: ROM, HA, and NZ at time zero. Complete capsular closure effectively restored these measures when compared with the intact condition. CLINICAL RELEVANCE: Cadaveric models consisting of the hip joint with surrounding soft tissue were used under laboratory testing conditions to investigate potential iatrogenic joint instability resulting from expansive capsulotomies, showing that complete capsular closure leads to reconstitution of original joint stability properties at time zero.

Function of the ligamentum teres in limiting hip rotation: a cadaveric study.

PURPOSE: The purpose of this cadaveric study was to evaluate the function of the ligamentum teres (LT) in limiting hip rotation in 18 distinct hip positions while preserving the capsular ligaments. METHODS: Twelve hips in 6 fresh-frozen pelvis-to-toes cadaveric specimens were skeletonized from the lumbar spine to the distal femur, preserving only the hip ligaments. Hip joints were arthroscopically accessed through a portal located between the pubofemoral and iliofemoral ligaments to confirm the integrity of the LT. Three independent measurements of hip internal and external rotation range of motion (ROM) were performed in 18 defined hip positions of combined extension-flexion and abduction-adduction. The LT was then arthroscopically sectioned and rotation ROM reassessed in the same positions. A paired sample t test was used to compare the average internal and external hip rotation ROM values in the intact LT versus resected conditions in each of the 18 positions. P < .0014 was considered significant. RESULTS: A statistically significant influence of the LT on internal or external rotation was found in 8 of the 18 hip positions tested (P < .0014). The major increases in internal and external rotation ROM occurred when the hip was in 90° or 120° of flexion. CONCLUSIONS: The major function of the LT is controlling hip rotation. The LT functions as an end-range stabilizer to hip rotation dominantly at 90° or greater of hip flexion, confirming its contribution to hip stability. CLINICAL RELEVANCE: Ruptures of the LT contribute to hip instability dominantly in flexed hip positions.

Diagnostic accuracy of clinical tests for sciatic nerve entrapment in the gluteal region.

PURPOSE: The purpose of this study was to determine the diagnostic accuracy of the straight leg raise (SLR), active piriformis, and seated piriformis stretch tests in identifying individuals with sciatic nerve entrapment. METHODS: Thirty-three individuals (female = 25 and male = 8) with a mean age of 43 years (range 15-64; SD ± 11 years) were included in the study. Twenty-three subjects had endoscopic findings of sciatic nerve entrapment. Ten subjects without entrapment during endoscopic assessment were used as a control group. The results of the SLR, active piriformis, and seated piriformis stretch tests were retrospectively reviewed for each subject and compared between both groups. The accuracy of these tests for the endoscopic finding of sciatic nerve entrapment was determined by calculating the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio. RESULTS: The SLR had sensitivity of 0.15, specificity of 0.95, positive likelihood ratio of 3.20, negative likelihood ratio of 0.90, and diagnostic odds ratio of 3.59. The active piriformis test had sensitivity of 0.78, specificity of 0.80, positive likelihood ratio of 3.90, negative likelihood ratio of 0.27, and diagnostic odds ratio of 14.40. The seated piriformis stretch test had sensitivity of 0.52, specificity of 0.90, positive likelihood ratio of 5.22, negative likelihood ratio of 0.53, and diagnostic odds ratio of 9.82. The most accurate findings were obtained when the results of the active piriformis test and seated piriformis stretch test were combined, with sensitivity of 0.91, specificity of 0.80, positive likelihood ratio of 4.57, negative likelihood ratio of 0.11, and diagnostic odds ratio of 42.00. CONCLUSIONS: The active piriformis and seated piriformis stretch tests can be used to help identify patients with and without sciatic nerve entrapment in the deep gluteal region.

Function of the ligamentum teres during multi-planar movement of the hip joint.

PURPOSE: The purpose of this study was to describe the orientation of the ligamentum teres and quantify the limb position when the ligamentum teres reached its endpoint during a simulated squat position in human cadavers. METHODS: Dissection of eight (4 male; 4 female) cadavers resulted in the complete removal of all soft tissue attachment of the femur to the acetabulum, leaving only the ligamentum teres intact. The limb was then moved into combined flexion and abduction of the hip joint to simulate a deep squat position until a ligamentous endpoint of the ligamentum teres was achieved. The orientation of the ligamentum teres in relation to the femoral head was described and the position of the limb relative to the sagittal plane (flexion) and frontal plane (abduction) was quantified. The mean, standard deviation, 95 % confidence intervals, and standard error of the measurement were calculated for the observed angles. RESULTS: Multi-planar movement of flexion and abduction moved the ligamentum teres into an anterior/inferior position relative to the femoral head and prevented the femoral head from anterior/inferior subluxation. The ligamentum teres endpoint was obtained at a combined average position of 100.6° (range 94°-112°; SD 5.5º; 95 % CI 96º-105º) and 20.0° (range 12°-32°; SD 7.0º; 95 % CI 14º-26º) flexion and abduction angle. CONCLUSIONS: The ligamentum teres formed a "sling-like" structure to support the femoral head inferiorly as the hip joint was moved into a combined position of flexion and abduction that resembled a squat position. The results help to define a possible role of the ligamentum teres in hip joint stability and possible mechanisms of injury.

Physiological changes as a result of hip arthroscopy performed with traction.

PURPOSE: To evaluate the physiological effects of hip arthroscopy using traction on venous blood flow, nerve conduction, soft-tissue injury, fibrinolysis, and patient pain. METHODS: Thirty subjects were prospectively analyzed in an institutional review board-approved study. The visual analog scale pain score, creatine phosphokinase (CPK)-MM level, and D-dimer test were obtained preoperatively, postoperatively, and 5 days postoperatively. Doppler ultrasound (group A) (n = 15) of femoral and popliteal venous blood flow and somatosensory evoked potentials (SSEPs) (group B) (n = 15) of the posterior tibial nerve and superficial peroneal nerve were monitored intraoperatively. RESULTS: Mean operation and traction times were 131.7 and 27.3 minutes, respectively. During traction (mean, 57.7 lb), decreased blood flow was determined at the popliteal vein (15 of 15 subjects) and femoral vein (4 of 15 subjects). Blood flow returned to baseline after traction in all subjects. Mean CPK-MM levels were 86.0 ± 29.6 mU/mL preoperatively, 232.1 ± 224.6 mU/mL postoperatively, and 138.1 ± 109.3 mU/mL at 5 days postoperatively. The number of subjects positive for D-dimer was 7 preoperatively, 12 postoperatively, and 21 at 5 days postoperatively. SSEPs showed a greater than 50% decrease in amplitude on the operative (8 of 15) and nonoperative (9 of 15) limbs. No significant correlations were determined between visual analog scale pain score, body mass index, CPK-MM level, traction time, or operating room time. CONCLUSIONS: Doppler ultrasound showed decreased blood flow of the popliteal vein with traction, which returned to normal after traction. SSEPs showed changes with and without traction on operative and nonoperative legs. Consideration should be given for knee flexion of the contralateral leg after traction to protect nerve function. Hip arthroscopy resulted in an increase in a positive D-dimer test from immediately postoperatively to postoperative day 5. There is variability in the soft-tissue damage with hip arthroscopy, which is independent of time (<2 hours), body mass index, or pain. Traction affects the vascular and neurologic structures of the operative and nonoperative extremity independent of time. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

The Development and validation of a self-administered quality-of-life outcome measure for young, active patients with symptomatic hip disease: the International Hip Outcome Tool (iHOT-33).

PURPOSE: The purpose of this study was to develop a self-administered evaluative tool to measure health-related quality of life in young, active patients with hip disorders. METHODS: This outcome measure was developed for active patients (aged 18 to 60 years, Tegner activity level ≥ 4) presenting with a variety of symptomatic hip conditions. This multicenter study recruited patients from international hip arthroscopy and arthroplasty surgeon practices. The outcome was created using a process of item generation (51 patients), item reduction (150 patients), and pretesting (31 patients). The questionnaire was tested for test-retest reliability (123 patients); face, content, and construct validity (51 patients); and responsiveness over a 6-month period in post-arthroscopy patients (27 patients). RESULTS: Initially, 146 items were identified. This number was reduced to 60 through item reduction, and the items were categorized into 4 domains: (1) symptoms and functional limitations; (2) sports and recreational physical activities; (3) job-related concerns; and (4) social, emotional, and lifestyle concerns. The items were then formatted using a visual analog scale. Test-retest reliability showed Pearson correlations greater than 0.80 for 33 of the 60 questions. The intraclass correlation statistic was 0.78, and the Cronbach α was .99. Face validity and content validity were ensured during development, and construct validity was shown with a correlation of 0.81 to the Non-Arthritic Hip Score. Responsiveness was shown with a paired t test (P ≤ .01), effect size of 2.0, standardized response mean of 1.7, responsiveness ratio of 6.7, and minimal clinically important difference of 6 points. CONCLUSIONS: We have developed a new quality-of-life patient-reported outcome measure, the 33-item International Hip Outcome Tool (iHOT-33). This questionnaire uses a visual analog scale response format designed for computer self-administration by young, active patients with hip pathology. Its development has followed the most rigorous methodology involving a very large number of patients. The iHOT-33 has been shown to be reliable; shows face, content, and construct validity; and is highly responsive to clinical change. In our opinion the iHOT-33 can be used as a primary outcome measure for prospective patient evaluation and randomized clinical trials.

Intra-abdominal fluid extravasation during hip arthroscopy: a survey of the MAHORN group.

PURPOSE: The purpose of this study was to survey experts in the field of hip arthroscopy from the Multicenter Arthroscopy of the Hip Outcomes Research Network (MAHORN) group to determine the frequency of symptomatic intra-abdominal fluid extravasation (IAFE) after arthroscopic hip procedures, identify potential risk factors, and develop preventative measures and treatment strategies in the event of symptomatic IAFE. METHODS: A survey was sent to all members of the MAHORN group. Surveys collected data on general hip arthroscopy settings, including pump pressure and frequency of different hip arthroscopies performed, as well as details on cases of symptomatic IAFE. Responses to the survey were documented and analyzed. RESULTS: Fifteen hip arthroscopists from the MAHORN group were surveyed. A total of 25,648 hip arthroscopies between 1984 and 2010 were reviewed. Arthroscopic procedures included capsulotomies, labral reattachment after acetabuloplasty, peripheral compartment arthroscopy, and osteoplasty of the femoral head-neck junction. Of the arthroscopists, 7 (47%) had 1 or more cases of IAFE (40 cases reported). The prevalence of IAFE in this study was 0.16% (40 of 25,650). Significant risk factors associated with IAFE were higher arthroscopic fluid pump pressure (P = .004) and concomitant iliopsoas tenotomy (P < .001). In all 40 cases, the condition was successfully treated without long-term sequelae. Treatment options included observation, intravenous furosemide, and Foley catheter placement, as well as 1 case of laparotomy. CONCLUSIONS: Symptomatic IAFE after hip arthroscopy is a rare occurrence, with an approximate prevalence of 0.16%. Prevention of IAFE should include close intraoperative and postoperative monitoring of abdominal distention, core body temperature, and hemodynamic stability. Concomitant iliopsoas tenotomy and high pump pressures may be risk factors leading to symptomatic IAFE. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Ligamentum teres: a functional description and potential clinical relevance.

PURPOSE: The primary purpose of this study was to investigate the role the ligamentum teres has in providing hip stability using a biomechanical model. The second purpose was to review arthroscopic findings in those with a complete ligamentum teres rupture and question them regarding instability to determine how clinical findings related to the biomechanical model. METHODS: A string model was created to examine ligamentum teres excursion during various hip positions. A retrospective review of 350 consecutive surgical patients identified 20 subjects with a complete ligamentum teres rupture that was not repaired at the time of surgery. RESULTS: The model found the ligamentum teres to have the greatest excursion when the hip was externally rotated in flexion (ER/FLEX) and internally rotated in extension (IR/EXT). During operative assessment, it was noted that all 20 subjects had laxity during dynamic impingement testing when their hip was in a position of ER/FLEX. Nine (45%) of the 20 subjects with ligamentum teres rupture were available for follow-up (mean 31 months post-op). Five out of these 9 subjects noted instability: 5 of 9 with squatting (ER/FLEX) and 4 of 9 with crossing one leg behind of the other (IR/EXT). These 5 subjects had osseous risk factors that compromised hip stability including inferior acetabular insufficiency. CONCLUSIONS: The ligamentum teres may contribute to hip stability when the hip is in ER/FLEX and IR/EXT. Individuals with osseous risk factors for instability, including inferior acetabular insufficiency, may have instability with squatting (ER/FLEX) and crossing one leg behind of the other (IR/EXT). LEVEL OF EVIDENCE: IV.

Preemptive analgesia in hip arthroscopy: intra-articular bupivacaine does not improve pain control after preoperative peri-acetabular blockade.

INTRODUCTION: Literature addressing postoperative pain management after hip arthroscopy is relatively scarce. This study aimed to assess if there was added analgesic benefit associated with postoperative intra-articular bupivacaine blockade for patients who received preoperative peri-acetabular blockade for hip arthroscopy procedures. METHODS: 52 patients were included in this comparative cohort study. Group 1 consisted of 20 patients who received preoperative peri-acetabular blockade and postoperative intra-articular blockade. The control group (Group 2), consisted of 32 patients who received only preoperative peri-acetabular blockade. Postoperative pain was recorded via visual analogue scale (VAS) pain scores, analgesic consumption, and pain diaries for 2 weeks postoperatively. RESULTS: Postoperative VAS pain scores were significantly lower in the experimental group at the 30-minute recovery room assessment (VAS scores Group 1: 1.1; Group 2: 3.00, p = 0.034). Other than the 30-minute recovery room assessment, VAS pain scores, narcotic medication consumption, and non-narcotic analgesic consumption did not differ between the 2 groups at any time point in the study period. CONCLUSIONS: This study did not demonstrate significant clinical benefit for patients who receive postoperative intra-articular blockade in addition to preoperative peri-acetabular blockade with bupivacaine 0.5%. We recommend the use of preoperative peri-acetabular bupivacaine blockade without intra-articular blockade postoperatively for pain control in the setting of hip arthroscopy surgery.

The endoscopic treatment of sciatic nerve entrapment/deep gluteal syndrome.

PURPOSE: The purpose of this study was to investigate the historical, clinical, and radiographic presentation of deep gluteal syndrome (DGS) patients, describe the endoscopic anatomy associated with DGS, and assess the effectiveness of endoscopic surgical decompression for DGS. METHODS: Sciatic nerve entrapment was diagnosed in 35 patients (28 women and 7 men). Portals for inspection of the posterior peritrochanteric space (subgluteal space) of the hip were used as well as an auxiliary posterolateral portal. Patients were treated with sciatic nerve decompression by resection of fibrovascular scar bands, piriformis tendon release, obturator internus, or quadratus femoris or by hamstring tendon scarring. Postoperative outcomes were evaluated with the modified Harris Hip Score (MHHS), verbal analog scale (VAS) pain score, and a questionnaire related specifically to sciatic hip pain. RESULTS: The mean patient age was 47 years (range, 20 to 66 years). The mean duration of symptoms was 3.7 years (range, 1 to 23 years). The mean preoperative VAS score was 6.9 ± 2.0, and the mean preoperative MHHS was 54.4 ± 13.1 (range, 25.3 to 79.2). Of the patients, 21 reported preoperative use of narcotics for pain; 2 continued to take narcotics postoperatively (unrelated to initial complaint). The mean time of follow-up was 12 months (range, 6 to 24 months). The mean postoperative MHHS increased to 78.0 and VAS score decreased to 2.4. Eighty-three percent of patients had no postoperative sciatic sit pain (inability to sit for >30 minutes). CONCLUSIONS: Endoscopic decompression of the sciatic nerve appears useful in improving function and diminishing hip pain in sciatic nerve entrapment/DGS.

Iliopsoas Muscle/Tendon Proportions at Three Levels of Described Arthroscopic Tenotomy: An Anatomic Study in Fresh Cadaveric Specimens.

PURPOSE: To calculate the iliopsoas muscle/tendon ratio at 3 levels of arthroscopic iliopsoas tenotomy sites in fresh cadaveric specimens. METHODS: An anatomic study design was performed using 16 iliopsoas musculotendinous units from the level of the hip joint to their insertion on the lesser trochanter. All specimens came from 16 fresh cadaveric specimens (10 male, 6 female), with a median age of 41 years (range 31-55.25 years). Circumferential measurements of the composite musculotendinous unit and the iliopsoas tendon were then made at the lesser trochanter insertion, the site of transcapsular tenotomy, and the site of tenotomy at the level of the labrum. Anatomical variance of the iliopsoas tendon at the insertion on the lesser trochanter and muscular extension below the lesser trochanter level also were described. The difference between the median circumference of the iliopsoas musculotendinous units or the isolated tendons at the 3 levels was calculated. RESULTS: The median circumference of the iliopsoas musculotendinous unit at the level of the labrum, orbicularis zone (transcapsular tenotomy site), and the lesser trochanter was 140.9 mm (range 137.9-148.9), 136.7 mm (range 132.9-140), and 99.5 mm (range 96.5-104.8), respectively. The median circumference of the iliopsoas tendon at these same levels was 25.6 mm (range 22.7-33.7), 28.9 mm (range 25.1-32.2), and 30.9 mm (range 27.9-36.1), respectively. Accordingly, the proportions of the iliopsoas muscle/tendon at the level of the labrum, the transcapsular tenotomy site, and the lesser trochanter insertion were 18% tendon/82% muscle, 21% tendon/79% muscle, and 31% tendon/69% muscle, respectively. CONCLUSIONS: The proportions of the iliopsoas muscle/tendon at the level of the labrum, the transcapsular tenotomy site and the lesser trochanter insertion were 18% tendon/82% muscle, 21% tendon/79% muscle, and 31% tendon/69% muscle, respectively. The distal muscular projection below the tendinous insertion on the lesser trochanter may maintain the functional connection of the iliopsoas between origin and insertion even after releasing the tendon. CLINICAL RELEVANCE: This finding may have implications for a new understanding of arthroscopic tenotomy of the iliopsoas around the hip, as previously described muscle/tendon proportions were not calculated in fresh cadavers.

The pattern and technique in the clinical evaluation of the adult hip: the common physical examination tests of hip specialists.

PURPOSE: The purpose of this study was to systematically evaluate the technique and tests used in the physical examination of the adult hip performed by multiple clinicians who regularly treat patients with hip problems and identify common physical examination patterns. METHODS: The subjects included 5 men and 6 women with a mean age (+/-SD) of 29.8 +/- 9.4 years. They underwent physical examination of the hip by 6 hip specialists with a strong interest in hip-related problems. All examiners were blind to patient radiographs and diagnoses. Patient examinations were video recorded and reviewed. RESULTS: It was determined that 18 tests were most frequently performed (>or=40%) by the examiners, 3 standing, 11 supine, 3 lateral, and 1 prone. Of the most frequently performed tests, 10 were performed more than 50% of the time. The tests performed in the supine position were as follows: flexion range of motion (ROM) (percentage of use, 98%), flexion internal rotation ROM (98%), flexion external rotation ROM (86%), passive supine rotation test (76%), flexion/adduction/internal rotation test (70%), straight leg raise against resistance test (61%), and flexion/abduction/external rotation test (52%). The tests performed in the standing position were the gait test (86%) and the single-leg stance phase test (77%). The 1 test in the prone position was the femoral anteversion test (58%). CONCLUSIONS: There are variations in the testing that hip specialists perform to examine and evaluate their patients, but there is enough commonality to form the basis to recommend a battery of physical examination maneuvers that should be considered for use in evaluating the hip. CLINICAL RELEVANCE: Patients presenting with groin, abdominal, back, and/or hip pain need to have a basic examination to ensure that the hip is not overlooked. A comprehensive physical examination of the hip will benefit the patient and the physician and serve as the foundation for future multicenter clinical studies.

Reliability of clinical diagnosis in intraarticular hip diseases.

This study investigated the ability of experienced orthopedic surgeons to agree on a diagnosis of labral tear, femoroacetabular impingement (FAI), and capsular laxity using clinical examination. Eight patients under the care of an experienced hip arthroscopist underwent independent clinical evaluations by six orthopedic surgeons who specialized in management hip pain. No attempt was made to regulate the evaluation process as surgeons performed their examination as they would in their own practice. Average subject age was 27 years (19-47 years) with five females and three males. Subjects subsequently underwent arthroscopic surgery by the treating surgeon. Surgical findings were recorded with respect to the presence or absence of a labral tear, FAI, and/or capsular laxity. The percent agreement between the surgical findings and clinical examinations were determined. Surgical findings noted four subjects had a labral tear, five FAI, and three laxity. Based on clinical examination, surgeons agreed 63, 65 and 58% of the time with the surgical diagnosis of labral tear, FAI, and capsular laxity, respectively. The level of agreement did not seem to be dependent on the size or type of labral tear. Also, the ability to detect FAI did not seem to depend on whether the lesion was a cam, pincer, combined cam/pincer or size of the cam lesion. This study offers support that clinical examination techniques used for making a diagnosis needs to be improved and standardized if they are to be useful in diagnosing specific pathologies found with arthroscopic hip surgery.

Pain management practice patterns after hip arthroscopy: an international survey.

Several post-operative pain control methods have been described for hip arthroscopy including systemic medications, intra-articular or peri-portal injection of local anesthetics and peripheral nerve blocks. The diversity of modalities used may reflect a lack of consensus regarding an optimal approach. The purpose of this investigation was to conduct an international survey to assess pain management patterns after hip arthroscopy. It was hypothesized that a lack of agreement would be present in the majority of the surgeons' responses. A 25-question multiple-choice survey was designed and distributed to members of multiple orthopedic professional organizations related to sports medicine and hip arthroscopy. Clinical agreement was defined as > 80% of respondents selecting a single answer choice, while general agreement was defined as >60% of a given answer choice. Two hundred and fifteen surgeons completed the survey. Clinical agreement was only evident in the use of oral non-steroidal anti-inflammatory drugs (NSAIDs) for pain management after hip arthroscopy. A significant number of respondents (15.8%) had to readmit a patient to the hospital for pain control in the first 30 days after hip arthroscopy in the past year. There is significant variability in pain management practice after hip arthroscopy. The use of oral NSAIDs in the post-operative period was the only practice that reached a clinical agreement. As the field of hip preservation surgery continues to evolve and expand rapidly, further research on pain management after hip arthroscopy is clearly needed to establish evidence-based guidelines and improve clinical practice.