Imaging changes following surgery for ischiofemoral impingement.

Partial resection of the lesser trochanter (LT plasty) has been increasingly recommended to treat ischiofemoral impingement. However, there is a lack of studies on the imaging findings following LT plasty. The purpose of this study was to assess magnetic resonance imaging (MRI) changes on the lesser trochanter and surrounding musculotendinous structures following LT plasty to treat ischiofemoral impingement. Twenty-one patients (21 hips) were studied. The LT length and cross-sectional area of the iliopsoas muscle were measured on MRI before and after surgery. The MRIs were performed on average 11 months (range, 3 to 25 months) after surgery. The mean ± standard deviation amount of LT resected (difference between pre- and postoperative LT length) was 7.3 mm ± 2.5 mm. The iliopsoas cross-sectional area decreased after the LT plasty in 95% of the hips (20/21) by an average of 35% ± 16%. The reduction in iliopsoas size had no significant correlation with improvement on the modified Harris Hip Score at a mean follow-up of 17 months after surgery (r = -0.13, P = 0.58). The iliopsoas muscle size decreased on average 35% following endoscopic LT plasty. The decrease was not correlated with midterm functional outcomes.

Anterior Electronic Hip Pain Drawings Are Helpful for Diagnosis of Intra-articular Sources of Pain: Lateral or Posterior Drawings Are Unreliable.

Purpose: The purpose of this study was to determine the accuracy of electronic hip pain drawing to diagnose intra-articular source of pain in nonarthritic hips, defined by response to an intra-articular injection. Methods: A retrospective assessment was performed in consecutive patients who had an intra-articular injection completed within a 1-year period. Patients were classified as responders or nonresponders to intra-articular hip injection. A positive injection was defined as greater than 50% hip pain relief within 2 hours after injection. Electronic pain drawings collected before injection were then evaluated according to the hip region marked by the patients. Results: Eighty-three patients were studied after applying inclusion and exclusion criteria. Anterior hip pain on drawing had a sensitivity of 0.69, specificity of 0.68, positive predictive value (PPV) of 0.86, and negative predictive value (NPV) of 0.44 for intraarticular source of pain. Posterior hip pain on drawing had a sensitivity of 0.59, specificity of 0.23, PPV of 0.68, and NPV of 0.17 for intra-articular source of pain. Lateral hip pain on drawing had a sensitivity of 0.62, specificity of 0.50, PPV of 0.78, and NPV of 0.32 for intraarticular source of pain. Conclusion: Anterior hip pain on electronic drawing has a sensitivity of 0.69 and specificity of 0.68 for intra-articular source of pain in nonarthritic hips. Lateral and posterior hip pain on electronic pain drawings are not reliable to rule out intra-articular hip disease. Level of Evidence: Level III, case-control study.

Acute Adductor Muscle Injury: A Systematic Review on Diagnostic Imaging, Treatment, and Prevention.

BACKGROUND: Controversies remain regarding the diagnosis, imaging, and treatment of acute adductor injuries in athletes. PURPOSE: To investigate the diagnostic imaging, treatment, and prevention of acute adductor injuries based on the most recent and relevant scientific evidence. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: The PubMed and Web of Science databases were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify articles studying acute adductor injury in athletes. Inclusion criteria were original publication on acute adductor injury in amateur or professional athletes, level 1 to 4 evidence, mean patient age >15 years, and results presented as return-to-sport, pain, or functional outcomes. Quality assessment was performed with the CONSORT (Consolidated Standards of Reporting Trials) statement or the methodological index for non-randomized studies criteria. Articles were grouped as imaging, treatment, prevention focused, or mixed. RESULTS: A total of 30 studies published between 2001 and 2021 were selected, involving 594 male patients with a mean age 26.2 years (range, 16-68 years). The most frequent sports were soccer (62%), basketball (14%), futsal (6%), American football (3%), and ice hockey and handball (2%). Risk factors for acute adductor injury were previous acute groin injury, adductor weakness compared with the uninjured side, any injury in the previous season, and reduced rotational hip range of motion. The frequency of complete adductor muscle tears on magnetic resonance imaging was 21% to 25%. For complete adductor tears, the average time to return to play was 8.9 weeks in patients treated nonoperatively and 14.2 weeks for patients treated surgically. Greater stump retraction was observed in individuals treated surgically. Partial acute adductor tears were treated nonoperatively with physical therapy in all studies in the present systematic review. The average time to return to play was 1 to 6.9 weeks depending on the injury grade. The efficacy of adductor strengthening on preventing acute adductor tears has controversial results in the literature. CONCLUSION: Athletes with partial adductor injuries returned to play 1 to 7 weeks after injury with physical therapy treatment. Nonoperative or surgical treatment is an acceptable option for complete adductor longus tendon tear.

Hip physical examination extension loss and radiographic osseous findings in patients with low back pain and nonarthritic hips.

The association between hip and spine abnormalities is frequent, and limitation in hip extension has been linked with low back pain. The purpose of this study was to assess the radiographic osseous findings in nonarthritic hips of patients with hip pain, low back pain, and limited hip extension. Ninety patients (92 hips) were included in this study. Hip extension was tested in the contralateral decubitus position with the hip in neutral abduction/adduction and neutral rotation. In sequence, hip extension was tested by adding passive abduction, followed by internal/external rotation of the hip. A hip extension limitation was defined as less than zero degrees of extension. Imaging studies were assessed for the following osseous morphologies: decreased ischiofemoral space (≤17 mm), increased femoral torsion (≥30°), decreased femoral torsion (≤5°), and posterior acetabular overcoverage. Fifty-seven out of 92 hips (62%) had at least one osseous imaging finding for limitation in hip extension: decreased ischiofemoral space (38/92, 41%), increased femoral torsion (5/92, 5%), decreased femoral torsion (24/92, 26%), and posterior acetabular overcoverage (21/92, 23%). Decreased ischiofemoral space, femoral torsional abnormalities, and/or posterior acetabular wall overcoverage are observed in imaging studies of most individuals with limitation of hip extension and low back pain.

Surgical Outcomes of Inguinal-, Pubic-, and Adductor-Related Chronic Pain in Athletes: A Systematic Review Based on Surgical Technique.

BACKGROUND: Controversies remain regarding the surgical treatment of inguinal-, pubic-, and adductor-related chronic groin pain (CGP) in athletes. PURPOSE: To investigate the outcomes of surgery for CGP in athletes based on surgical technique and anatomic area addressed. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: The PubMed and Embase databases were searched for articles reporting surgical treatment of inguinal-, pubic-, or adductor-related CGP in athletes. Inclusion criteria were level 1 to 4 evidence, mean patient age >15 years, and results presented as return-to-sport, pain, or functional outcomes. Quality assessment was performed with the CONSORT (Consolidated Standards of Reporting Trials) statement or MINORS (Methodological Index for Non-randomized Studies) criteria. Techniques were grouped as inguinal, adductor origin, pubic symphysis, combined inguinal and adductor, combined pubic symphysis and adductor, or mixed. RESULTS: Overall, 47 studies published between 1991 and 2020 were included. There were 2737 patients (94% male) with a mean age at surgery of 27.8 years (range, 12-65 years). The mean duration of symptoms was 13.1 months (range, 0.3-144 months). The most frequent sport involved was soccer (71%), followed by rugby (7%), Australian football (5%), and ice hockey (4%). Of the 47 articles reviewed, 44 were classified as level 4 evidence, 1 study was classified as level 3, and 2 randomized controlled trials were classified as level 1b. The quality of the observational studies improved modestly with time, with a mean MINORS score of 6 for articles published between 1991 and 2000, 6.53 for articles published from 2001 to 2010, and 6.9 for articles published from 2011 to 2020. Return to play at preinjury or higher level was observed in 92% (95% CI, 88%-95%) of the athletes after surgery to the inguinal area, 75% (95% CI, 57%-89%) after surgery to the adductor origin, 84% (95% CI, 47%-100%) after surgery to the pubic symphysis, and 89% (95% CI, 70%-99%) after combined surgery in the inguinal and adductor origin. CONCLUSION: Return to play at preinjury or higher level was more likely after surgery for inguinal-related CGP (92%) versus adductor-related CGP (75%). However, the majority of studies reviewed were methodologically of low quality owing to the lack of comparison groups.

Usefulness of magnetic resonance imaging to diagnose greater trochanteric-ischial impingement.

Extra-articular impingement between the femur and ischium is increasingly recognized as a cause of hip pain. The purpose of this study was to assess the diagnostic parameters for greater trochanteric-ischial impingement (GTI) in magnetic resonance imaging (MRI) studies. Seven patients (seven hips) diagnosed with GTI were retrospectively identified. For each of these seven patients, three controls were matched by gender, height, and weight to create a control group of 21 asymptomatic hips. The same technique and positioning were utilized to acquire the MRIs in the GTI and control groups. The MRI was performed with the lower limbs in a functional position reproducing the midstance phase of the gait cycle. The greater trochanteric-ischial distance was measured in the axial cut showing the shortest distance between the greater trochanter and the ischial tuberosity. The mean greater trochanteric-ischial distance was 26.2 mm in the GTI group and 33.8 mm in the control group (P < 0.01). Greater trochanteric-ischial distance ≤28 mm had a sensitivity of 86% and specificity of 86% in identifying GTI. In conclusion, utilizing MRI with functional positioning of the lower limbs, greater trochanter-ischial distance ≤28 mm is helpful to diagnose GTI in women.

Low Back Pain Improves After Surgery for Lesser Trochanteric-Ischial Impingement.

PURPOSE: To assess the effects of surgery for lesser trochanteric-ischial impingement (LTI) on low back pain. METHODS: The records of patients with LTI who underwent endoscopic partial resection of the lesser trochanter (LT) between May of 2017 and February of 2019 were reviewed. Inclusion criteria were the presence of low back pain in association with hip pain, diagnosis of LTI, and partial resection of the LT to treat LTI. Exclusion criteria were less than 12 months of postoperative follow-up and hip or spine surgery after the LTI surgery. Patients were assessed before surgery and at the most recent follow-up with the modified Harris Hip Score and Oswestry Disability Index for lumbar spine. RESULTS: Thirty patients (31 hips) met the inclusion criteria. Four patients were lost to follow-up. Two patients with borderline dysplasia and grade 1 and 2 osteoarthritis underwent total hip arthroplasty after the partial resection of the LT. The results are presented considering the remaining 24 patients (25 hips). The average age at surgery was 51 years (range 32-65 years). The mean follow-up after the surgery for LTI was 19 months (range 12-35 months). The mean ± SD ODI improved from 48% ± 15 before the LTI surgery to 21% ± 22 (P < .001) at the most recent follow-up. Improvement in the Oswestry Disability Index above the minimal clinical important difference was observed in 16 patients (67%) following the LTI surgery. The mean ± SD modified Harris Hip Score improved from 55.8 ± 14 before LTI surgery to 81.3 ± 14.3 (P < .001). CONCLUSIONS: Decrease in low back pain above the minimal clinically important difference is observed in 2 of 3 patients after partial resection of the LT. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Femoral Derotation Osteotomy Improves Hip and Spine Function in Patients With Increased or Decreased Femoral Torsion.

PURPOSE: To evaluate the outcomes of proximal femoral derotation osteotomy (PFDO) on the hip and spine function of patients with abnormal femoral torsion. METHODS: This retrospective study included patients who underwent PFDO to treat increased or decreased femoral torsion between July 2014 and February 2019. The exclusion criteria were: previous fracture, fixation of slipped capital femoral epiphysis or osteotomy in the ipsilateral femur; PFDO associated to varus or valgus osteotomy; Tönnis grade 2 or 3 osteoarthritis; and PFDO performed to treat knee abnormalities. Hip function was assessed through the modified Harris Hip Score (mHHS). A subgroup of consecutive patients with low back pain before the PFDO and operated after 2017 had the spine function assessed through the Oswestry disability index (ODI). RESULTS: A total of 37 hips (34 patients) were studied: 15 hips with increased femoral torsion and 22 with decreased femoral torsion. Eight patients were male and 26 were female. The average age at PFDO was 33 years (range, 15-54 years). At a mean follow-up of 24 months (range, 12-65 months), the mean mHHS improved from 58.1 ± 14.3 before PFDO to 82 ± 15.6 at the most recent follow-up (P < .001). Improvement in the mHHS above the minimum clinically important difference (MCID) was observed in 33 hips (89%). In the subgroup of 14 consecutive patients with ODI available, the ODI improved from a mean of 45% ± 16% before the PFDO to 22% ± 17% at the most recent follow-up (P = .001). Nine (64.3%) of the 14 patients presented improvement in the ODI above the MCID. Revision procedure with a larger intramedullary nail was necessary in 2 hips to treat nonunion. CONCLUSION: Proximal femoral derotation osteotomy improves the hip and spine function in patients with increased or decreased femoral torsion and nonarthritic hips. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Spinopelvic Parameters Do Not Predict the Sagittal Orientation of the Acetabulum.

BACKGROUND: The orientation of the acetabulum has a fundamental role in impingement and instability of the hip, and the spinopelvic parameters are thought to predict the sagittal orientation of the acetabulum (SOA). However, similar to the acetabular version (axial orientation) and inclination (coronal orientation), the cephalic or caudal orientation of the acetabulum in the sagittal plane, or SOA, may primarily be an intrinsic feature of the acetabulum itself. PURPOSE: To determine whether the spinopelvic parameters predict the sagittal orientation of the acetabulum in individuals without lumbar deformity. STUDY DESIGN: Cross-sectional study; Level of evidence, 4. METHODS: A retrospective analysis was performed in 89 patients (94 hips; 62 female, 27 male; mean ± SD age, 45.9 ± 15.4 years) without lumbosacral deformity who underwent magnetic resonance arthrogram (MRA) for assessment of hip pain. The SOA was determined in the sagittal cut MRA. A line was drawn at the distal limit of the anterior and posterior acetabular horns longitudinally to the transverse ligament, and the angle between this line and the axial plane represented the SOA. The sacral slope, pelvic incidence, and spinopelvic tilt were determined using a 3-dimensional cursor and the axial, sagittal, and coronal cuts. All MRA studies were performed with the patient in the supine position. RESULTS: The SOA had a mean ± SD cephalic orientation of 18° ± 6.6°. No significant correlation was observed between the SOA and the sacral slope (r = -0.03; P = .77). A weak correlation was observed between the SOA and the pelvic incidence (r = 0.22; P = .03) and between the SOA and the spinopelvic tilt (r = 0.41; P < .01). CONCLUSION: The SOA cannot be presumed based on the spinopelvic parameter. Similar to the well-known parameters to assess the axial and coronal orientation of the acetabulum, the assessment of the SOA demands acetabular-specific parameters. Additional studies are necessary to assess the SOA in asymptomatic hips, including disparities between genders. Clinically significant values for abnormal SOA of the acetabulum remain to be defined.

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.

Snapping of the Sciatic Nerve and Sciatica Provoked by Impingement Between the Greater Trochanter and Ischium: A Case Report.

CASE: A 64-year-old woman developed worsening sciatica associated with snapping at the hip over a period of 4 years. The physical examination and dynamic ultrasound revealed the snapping of the sciatic nerve (SN) provoked by impingement between the greater trochanter (GT) and the ischium. Additional imaging studies demonstrated hyperintense signal in the SN at the hip, sagittal imbalance, decreased ischiofemoral space, and increased femoral torsion. CONCLUSION: Snapping and entrapment of the SN provoked by impingement between the GT and the ischium should be considered in the differential diagnosis of snapping hip and/or sciatica.

Frequency of ischiofemoral space discrepancy when comparing magnetic resonance images of distinct institutions for the same patient.

Inaccuracy of ischiofemoral space (IFS) measurement may result in radiographic misdiagnosis of ischiofemoral impingement, as well as insufficient or excessive osseous resection when surgery is indicated. This study compared the IFS measured in magnetic resonance imaging (MRI) performed in distinct health services for the same patient. Sixty-five patients (95 hips) who had hip MRI performed at an outside institution (noncontrolled MRI) followed by a hip MRI with lower extremity positioning reproducing the standing position (controlled MRI) were studied. For each hip, the IFS measured in the noncontrolled MRI was compared to the IFS measured in the controlled MRI. The categorization of a hip as presenting decreased IFS (≤17 mm) or normal IFS (>17 mm) changed in 19% of the hips when comparing the noncontrolled MRI to the controlled MRI. From the 32 hips (34%) with a difference ≥4 mm in the IFS, the predominant positioning change was hip flexion/extension in 47%, hip rotation in 44%, and hip abduction/adduction in 9%. In conclusion, a difference >4 mm in the IFS was observed in 1 out of every 3 hips when comparing noncontrolled MRI with controlled MRI reproducing the lower limb positioning in the standing position.

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.

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.

Parameters for assessment of the inferior acetabulum morphology in 300 adult hips.

The inferior acetabulum (IA) has been studied as a stabilizer of the hip in flexed positions with potential implications in femoroacetabular impingement and hip instability. However, there is a paucity of studies considering the normal morphology and parameters for assessment of the IA. The purpose of this study was to define parameters to assess the IA morphology and their normal range. Specifically, the objectives were to assess: (i) the width of the anterior horn (AH) and posterior horn (PH) of the acetabulum; (ii) the inclination of the articular surface of the AH angle (AHA) and PH angle (PHA) in the axial plane; (iii) the anterior opening angle of the IA and differences between genders. One hundred and fifty adult skeletons were utilized in this study. Measurements were taken directly from acetabula in 300 innominate bones utilizing digital calipers. In sequence, the innominate bones were assembled to sacrum and 150 pelvises were digitally photographed in standardized positions. Angular parameters of the acetabulum were then measured utilizing the Adobe Photoshop software. The mean width of the AH was 14.80 ± 2.35 mm (range 9.44-20.88). The mean width of the PH was 19.72 ± 2.61 mm (range 13.16-25.86). The AHA was on average 43.58 ± 7.10° (range 24.70-64) and the PHA was on average 36.07 ± 7.54° (16.10-53.20). The mean anterior opening angle of the IA was 25.33 ± 5.40° (10.90-43.10). The IA morphology can be evaluated in all anatomical planes through quantitative parameters. The assessment of the osseous morphology of the IA is the first step to elucidate abnormalities of the IA as potential source of hip pain.

Alignment of the tibial component in total knee arthroplasty procedures using an intramedullary or extramedullary guide: double-blind randomized prospective study.

OBJECTIVES: To evaluate the results obtained through using an intramedullary or extramedullary guide for sectioning the tibia in total knee arthroplasty procedures, with a view to identifying the accuracy of these guides and whether one might be superior to the other. METHODS: This was a randomized double-blind prospective study on 41 total knee arthroplasty procedures performed between August 2011 and March 2012. The angle between the base of the tibial component and the mechanical axis of the tibia was measured during the immediate postoperative period by means of radiography in anteroposterior view on the tibia that encompassed the knee and ankle. RESULTS: There was no demographic difference between the two groups evaluated. The mean alignment of the tibial component in the patients of group A (intramedullary) was 90.3° (range: 84-97°). In group B (extramedullary), it was 88.5° (range: 83-94°). CONCLUSION: In our study, we did not find any difference regarding the precision or accuracy of either of the guides. Some patients present an absolute or relative contraindication against using one or other of the guides. However, for the other cases, neither of the guides was superior to the other one.

OBJETIVOS: Avaliar os resultados obtidos com o uso de guia intramedular ou extramedular para o corte tibial em artroplastias totais do joelho, com vistas a identificar sua acurácia e a superioridade de um em relação ao outro. MÉTODOS: Estudo prospectivo, randomizado, duplo cego de 41 artroplastias totais de joelho feitas entre agosto de 2011 e março de 2012. Foi medido o ângulo entre a base do componente tibial e o eixo mecânico da tíbia no período pós-operatório imediato por meio de radiografia em incidência anteroposterior da tíbia que englobou joelho e tornozelo. RESULTADOS: Não houve diferença demográfica entre os dois grupos avaliados. O alinhamento médio do componente tibial nos pacientes do grupo A (intramedular) foi de 90,3° (84°-97°). No grupo B (extramedular), foi de 88,5° (83°-94°). CONCLUSÃO: Não encontramos, em nosso estudo, diferença quanto à precisão ou acurácia de qualquer um dos guias. Alguns pacientes apresentam contraindicação, absoluta ou relativa, para o uso de um ou outro guia. Todavia, para os demais casos, não há superioridade de algum deles.

Alignment of the tibial component in total knee arthroplasty procedures using an intramedullary or extramedullary guide: double-blind randomized prospective study / Alinhamento do componente tibial em artroplastia total do joelho com o uso de guia intramedular ou extramedular: um estudo prospectivo, randomizado, duplo cego

OBJECTIVES: To evaluate the results obtained through using an intramedullary or extramedullary guide for sectioning the tibia in total knee arthroplasty procedures, with a view to identifying the accuracy of these guides and whether one might be superior to the other. METHODS: This was a randomized double-blind prospective study on 41 total knee arthroplasty procedures performed between August 2011 and March 2012. The angle between the base of the tibial component and the mechanical axis of the tibia was measured during the immediate postoperative period by means of radiography in anteroposterior view on the tibia that encompassed the knee and ankle. RESULTS: There was no demographic difference between the two groups evaluated. The mean alignment of the tibial component in the patients of group A (intramedullary) was 90.3° (range: 84-97°). In group B (extramedullary), it was 88.5° (range: 83-94°). CONCLUSION: In our study, we did not find any difference regarding the precision or accuracy of either of the guides. Some patients present an absolute or relative contraindication against using one or other of the guides. However, for the other cases, neither of the guides was superior to the other one. .

OBJETIVOS: Avaliar os resultados obtidos com o uso de guia intramedular ou extramedular para o corte tibial em artroplastias totais do joelho, com vistas a identificar sua acurácia e a superioridade de um em relação ao outro. MÉTODOS: Estudo prospectivo, randomizado, duplo cego de 41 artroplastias totais de joelho feitas entre agosto de 2011 e março de 2012. Foi medido o ângulo entre a base do componente tibial e o eixo mecânico da tíbia no período pós-operatório imediato por meio de radiografia em incidência anteroposterior da tíbia que englobou joelho e tornozelo. RESULTADOS: Não houve diferença demográfica entre os dois grupos avaliados. O alinhamento médio do componente tibial nos pacientes do grupo A (intramedular) foi de 90,3° (84°-97°). No grupo B (extramedular), foi de 88,5° (83°-94°). CONCLUSÃO: Não encontramos, em nosso estudo, diferença quanto à precisão ou acurácia de qualquer um dos guias. Alguns pacientes apresentam contraindicação, absoluta ou relativa, para o uso de um ou outro guia. Todavia, para os demais casos, não há superioridade de algum deles. .

A MRI study of the lesser trochanteric version and its relationship to proximal femoral osseous anatomy.

The purpose of this study is to quantify the lesser trochanteric version and determine the angle and the relationship between lesser trochanter and femoral neck version. Investigate the influence of the lesser trochanter version in the width of ischiofemoral space. Two hundred and fifty asymptomatic hips were evaluated with axial magnetic resonance image. The lesser trochanter version was calculated. The difference between the femoral neck version and the lesser trochanter version formed the angle between each structure. The width of ischiofemoral space was measured and its relationship with the lesser trochanter version was determined. The mean lesser trochanter version was -24° ± 11.5° (range, - 54° to + 17°) with a coefficient variation of 47.45%. The mean femoral neck version measured 14.0° ± 10.8° (range, -16° to 50°), with a coefficient variation of 81.32%. The lesser trochanter/femora neck angle was 38.4° ± 9.6° (range, 8° to 67°), coefficient variation of 30%, with a moderate correlation between the structures (r = 0.63, P < 0.01). The mean ischiofemoral space was 22.9.0 ± 7.0 mm (range, 10.3 to 55 mm), and a weak correlation was found between ischiofemoral space and lesser trochanteric version (r = -0.16, P < 0.05). The lesser trochanteric version showed a high variation with a moderate relationship with the femoral neck version. The lesser trochanteric version does not influence the width of the ischiofemoral space.

Diagnosis and 2-year outcomes of endoscopic treatment for ischiofemoral impingement.

PURPOSE: The purposes of this study were to investigate the clinical and radiographic presentation of patients with ischiofemoral impingement (IFI) and to assess the outcomes of endoscopic treatment with partial resection of the lesser trochanter. METHODS: Five patients with IFI who underwent endoscopic treatment with partial resection of the lesser trochanter were retrospectively reviewed. The outcomes were assessed at a mean follow-up of 2.3 years (range, 2 to 2.5 years) through the modified Harris Hip Score and a visual analog scale score for pain. Physical examination tests provoking the impingement between the lesser trochanter and ischium were used for the diagnosis of IFI, including the IFI test and reproducible pain lateral to the ischium with the long-stride walking test. The presence of quadratus femoris muscle edema and a decreased ischiofemoral space on magnetic resonance imaging was also necessary for the diagnosis. RESULTS: The mean modified Harris Hip Score increased from 51.3 points (range, 34.1 to 73.7 points) preoperatively to 94.2 points (range, 78.1 to 100 points) at the final follow-up (P = .003). The mean visual analog scale score for pain decreased from 6.6 (range, 6 to 7.3) before surgery to 1 (range, 0 to 4) at the final follow-up (P = .001). The mean duration to return to sport after surgery was 4.4 months (range, 1 to 7 months) for the 5 patients in this study. No complication was observed. CONCLUSIONS: The endoscopic treatment of IFI was effective at 2 years in 5 patients with consistent clinical and imaging diagnostic findings. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

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.