Greater trochanter of the hip: attachment of the abductor mechanism and a complex of three bursae--MR imaging and MR bursography in cadavers and MR imaging in asymptomatic volunteers

Contributions of the Abductor Muscles to Rotational and Distractive Stability of the Hip in a Biomechanical Cadaveric Model

Background

The gluteus minimus (GMin) and gluteus medius (GMed) are important dynamic stabilizers of the hip, but quantitative data on their biomechanical roles in stabilizing the hip are currently lacking.

Purpose

To (1) establish a reproducible biomechanical cadaveric model of the hip abductor complex and (2) characterize the effects of loading the GMin and GMed on extraneous femoral rotation and distraction.

Study Design

Controlled laboratory study.

Methods

A total of 10 hemipelvises were tested in 4 muscle loading states: (1) unloaded, (2) the GMin loaded, (3) the GMed loaded, and (4) both the GMin and GMed loaded. Muscle loads were applied via cables, pulleys, and weights attached to the tendons to replicate the anatomic lines of action. Specimens were tested under internal rotation; external rotation; and axial traction forces at 0°, 15°, 30°, 60°, and 90° of hip flexion.

Results

When loaded together, the GMin and GMed reduced internal rotation motion at all hip flexion angles (P < .05) except 60° and reduced external rotation motion at all hip flexion angles (P < .05) except 0°. Likewise, when both the GMin and GMed were loaded, femoral distraction was decreased at all angles of hip flexion (P < .05).

Conclusion

The results of this study demonstrated that the GMin and GMed provide stability against rotational torques and distractive forces and that the amount of contribution depends on the degree of hip flexion.

Clinical Relevance

Improved understanding of the roles of the GMin and GMed in preventing rotational and distractive instability of the hip will better guide treatment of hip pathologies and optimize nonoperative and operative therapies.

Diagnostic Accuracy of Clinical Tests for Assessing Greater Trochanteric Pain Syndrome: A Systematic Review With Meta-analysis

OBJECTIVE: We aimed to evaluate the accuracy of clinical tests that are used to diagnose greater trochanteric pain syndrome (GTPS) in clinical practice. DESIGN: Diagnostic test accuracy systematic review with meta-analysis. LITERATURE SEARCH: MEDLINE, Embase, CINAHL, AMED, and SPORTDiscus were searched using key words mapped to diagnostic test accuracy for GTPS. STUDY SELECTION CRITERIA: Studies with published or derivable diagnostic accuracy data were included. DATA SYNTHESIS: Risk of bias was assessed using the QUADAS-2 tool, and certainty of evidence, via the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. MetaDTA "R" random-effects models were used to summarize individual and pooled data including sensitivity, specificity, likelihood ratios, and pretest/posttest probabilities. RESULTS: From a database yield of 858 studies, 23 full texts were assessed. We included 6 studies for review, involving 15 tests and 272 participants (314 hips). Overall certainty of evidence ranged from very low to moderate. Meta-analysis of 6 tests revealed sequenced test clusters able to significantly shift pretest-posttest probability for or against a GTPS diagnosis. In people reporting lateral hip pain, a negative gluteal tendon (GT) palpation test followed by a negative resisted hip abduction test significantly reduced the posttest probability of GTPS from 59% to 14%. In those with a positive GT palpation test followed by a positive resisted hip abduction test, the posttest probability of GTPS significantly shifted from 59% to 96%. CONCLUSION: The value of magnetic resonance imaging for diagnosing GTPS is debated. We have identified a straightforward, clinically useful diagnostic test cluster to help confirm or refute the presence of GTPS in people reporting lateral hip pain. J Orthop Sports Phys Ther 2024;54(1):1-24. Epub 10 August 2023. doi:10.2519/jospt.2023.11890.

Excision of trochanteric bursa during total hip replacement: Does it reduce the incidence of post-operative trochanteric bursitis?

BACKGROUND

Trochanteric bursitis is a common complication following total hip replacement (THR), and it is associated with high level of disability and poor quality of life. Excision of the trochanteric bursa prophylactically during THR could reduce the occurrence of post-operative trochanteric bursitis.

AIM

To evaluate whether synchronous trochanteric bursectomy at the time of THR affects the incidence of post-operative trochanteric bursitis.

METHODS

This retrospective cohort study was conducted in the secondary care setting at a large district general hospital. Between January 2010 and December 2020, 954 patients underwent elective primary THR by two contemporary arthroplasty surgeons, one excising the bursa and the other not (at the time of THR). All patients received the same post-operative rehabilitation and were followed up for 1 year. We reviewed all cases of trochanteric bursitis over this 11-year period to determine the incidence of post-THR bursitis. Two proportion Z-test was used to compare incidences of trochanteric bursitis between groups.

RESULTS

554 patients underwent synchronous trochanteric bursectomy at the time of THR whereas 400 patients did not. A total of 5 patients (incidence 0.5%) developed trochanteric bursitis following THR; 4 of whom had undergone bursectomy as part of their surgical approach, 1 who had not. There was no statistically significant difference between the two groups (Z value 1.00, 95%CI: -0.4% to 1.3%, P = 0.32). There were also 8 other patients who had both trochanteric bursitis and hip osteoarthritis prior to their THR; all of whom were treated with THR and synchronous trochanteric bursectomy, and 7 had resolution of their lateral buttock pains but 1 did not.

CONCLUSION

Synchronous trochanteric bursectomy during THR does not materially affect the incidence of post-operative bursitis. However, it is successful at treating patients with known trochanteric bursitis and osteoarthritis requiring THR.

Natural History of Degenerative Hip Abductor Tendon Lesions

BACKGROUND

The best treatment of degenerative hip abductor tendon lesions remains largely unknown, as the natural course of the disease has not yet been reported. The aim of the present study was to investigate the natural history of symptomatic degenerative hip abductor lesions.

HYPOTHESIS

Nonoperatively treated hip abductor lesions progress over time, resulting in refractory hip pain and low functional outcomes.

STUDY DESIGN

Case series (prognosis); Level of evidence, 4.

METHODS

Consecutive patients with greater trochanteric pain syndrome and degenerative changes on magnetic resonance imaging (MRI) of the symptomatic hip were included. Bilateral hip MRI scans and a clinical examination were performed at a minimum follow-up of 36 months to study the type and location of hip abductor lesion. Progression of a lesion was defined as a more severe lesion as compared with the initial MRI results or if the lesion extended to another, initially not involved, trochanteric facet. The muscle's fatty infiltration (FI) was also described.

RESULTS

From 106 patients identified, 58 patients (64 hips) aged 66 ± 14 years (mean ± SD) agreed to return to the clinic for follow-up MRI and met the inclusion criteria. At a mean 71-month follow-up, an overall 34% (22/64) of lesions had progressed over time: from trochanteric bursitis to tendinopathy (9/64, 14%) or partial tear (5/64, 8%), from tendinopathy to partial tear (4/64, 6%), from a partial to complete tear (3/64, 4.5%), and with 1 complete tear (1/64, 1.5%) extending to another trochanteric facet. Interestingly, 90% of partial tears remained stable or transformed into a scar. Although patients with a progressive lesion experienced more trochanteric pain (visual analog scale, 4.6 vs 2.8; P = .001), the functional outcomes were comparable with patients with a stable lesion. The majority of hips with a partial tear (64%) demonstrated a progression of gluteus minimus FI from a median grade of 1 to 2, whereas only 1 hip (3%) progressed from grade 2 to 3. Only 3 hips (9%) with a partial tear had a progression of gluteus medius FI, which did not differ significantly from the contralateral unaffected side.

CONCLUSION

Nonoperative treatment might be a valid long-term option for degenerative hip abductor lesions, especially for partial tears, which demonstrated a low risk of clinically relevant progression or muscle FI and similar clinical outcomes to those reported in the literature for operatively treated hip abductor tendon lesions.

US and MRI of Pelvic Tendon Anatomy and Pathologic Conditions

The bony pelvis serves as the attachment site for a large number of powerful muscles and tendons that drive lower extremity movement. Organizing the pelvic tendons into groups that share a common function and anatomic location helps the radiologist systematically evaluate these structures for injury, which can be caused by repetitive stress, acute trauma, or failure of degenerated tissues. Tears of the anteromedial adductors around the pubic symphysis and anterior flexors traversing anterior to the hip principally affect younger male athletes. Tears of the lateral abductors and posterior extensors are more common in older individuals with senescent tendinosis. The deep external rotators are protected and rarely injured, although they can be impinged. Imaging of the pelvic tendons relies primarily on US and MRI; both provide high spatial and contrast resolution for soft tissues. US offers affordable point-of-care service and dynamic assessment, while MRI allows simultaneous osseous and articular evaluation and is less operator dependent. While the imaging findings of pelvic tendon injury mirror those at appendicular body sites, radiologists may be less familiar with tendon anatomy and pathologic conditions at the pelvis. The authors review pertinent anatomy and imaging considerations and illustrate common injuries affecting the pelvic tendons. Online supplemental material is available for this article. ^©RSNA, 2022.

Lateral trochanteric bursa repair improves early hip function after posterior approach total hip arthroplasty: a prospective randomized control trial

BACKGROUND

The trochanteric bursa (TB) is an anatomic structure, which is dissected during posterior/lateral hip approaches in Total Hip Arthroplasty (THA). Some surgeons prefer to simply resect the bursa as they believe that it may be responsible for postoperative lateral trochanteric pain (LTP). Others advocate that this tissue acts as a buffer minimizing friction between soft tissue and bone, and therefore its repair may prevent LTP after THA.

AIM

The purpose of this prospective randomized controlled trial was to compare the clinical results of either resecting or repairing the TB during posterior approach THA.

METHODS

Forty-two patients with primary hip osteoarthritis undergoing THA via a posterior hip approach were randomly assigned to two groups; Group A, or TB resection group and Group B, or TB repair group. All patients in both groups were evaluated postoperatively in terms of hip function, measured by the Harris Hip Score (HHS), at 6 weeks, 3 months, 6 months, and 12 months after surgery, as well as LTP during daily routine activities and lying on the operative side.

RESULTS

Forty patients completed the study. Postoperative difference in terms of leg length and femoral offset was similar among the two groups (P = 0.467 and P = 0.39, respectively). At 6 weeks, patients in Group B had higher HHS (P = 0.052) and experienced less LTP when lying on the operative side (P = 0.046) but not during activities (P = 0.759). Thereafter, all functional parameters measured had comparable values in both groups. Subgroup analysis failed to identify any correlation between high offset stems and LTP.

CONCLUSION

TB repair in posterior approach THA improves hip functional recovery as well as patients' ability to lie on the operative side during the early postoperative period.

Subtrochanteric osteotomy in the management of femoral maltorsion results in anteroposterior malcorrection of the greater trochanter: computed simulations of 3D surface models of 100 cadavers

AIM

The purpose of this study was to investigate the greater trochanter's (GT) behaviour in simulated subtrochanteric osteotomy.

MATERIALS AND METHODS

Measurement of functional and anatomical femoral torsion, and position of the GT and lesser trochanter was performed using 3-dimensional (3D) surface models of 100 cadaveric femora. Femoral torsion between 2° and 22° was defined as normal, femora with <2° and >22° of femoral torsion were assigned to the low- and high-torsion group. Subtrochanteric osteotomy was simulated to normalise torsional deformities to 12°.

RESULTS

With subtrochanteric osteotomy, functional torsion was simultaneously corrected while adjusting anatomical torsion (R² = 0.866, p < 0.001). Compared to the normal-torsion group, an anteroposterior (AP) overcorrection of ±0.5 centimetres (range 0.02-1.1 cm) of the GT resulted in the high- and low-torsion group, respectively (p < 0.001): Mean AP GT distance to a standardised coronal plane was 2.1 ± 0.3 cm (range 12-30 cm) in the normal-torsion group compared to 1.61 ± 0.1 cm (range 1.4-1.71 cm) and 2.6 ± 0.6 cm (range 1.8-3.6 cm) for the corrected high and low-torsion groups, respectively. The extent of the GT shift in AP direction correlated strongly with the extent to which anatomical femoral torsion was corrected (R² = 0.946; p < 0.001).

CONCLUSIONS

Subtrochanteric osteotomy for femoral maltorsion reliably adjusts anatomical and functional torsion, but also results in a ±1 cm AP shift of the GT per 10° of torsional correction. However, this effect of the procedure is most likely not clinically relevant in relation to hip abductor performance.

Gluteus minimus tendon: MR imaging features and patterns of tendon tearing

PURPOSE

To highlight the spectrum of pathology and patterns of gluteus minimus tendon tearing observed on MR imaging of the hip.

METHODS AND MATERIALS

Retrospective review of consecutive hip MRI exams with findings of gluteus minimus tendon (GMin) pathology. A total of 194 exams in 178 patients (148 female, mean age 61) were reviewed. MRI exams are assessed for GMin: tendinopathy, partial, or complete tendon tears. GMin muscular fatty atrophy, enthesopathic cortical irregularities of the greater trochanter (GT), and peri-trochanteric edema or bursal fluid collections were assessed in all cases. In all cases of complete GMin tendon tearing, position and relationship of GMin tendon were assessed relative to its normal insertion site and adjacent soft tissues.

RESULTS

Clinical indications for MR imaging included hip pain (n = 151), and weakness or altered gait (n = 13). Insertional GMin tendinopathy was seen in 72, partial tearing in 81, and complete tendon tearing in 40 cases. Complete tendon tearing without proximal retraction was observed in 38/40 cases with soft tissue continuity visualized between distal tendon fibers and the proximal vastus lateralis muscle. Peri-trochanteric bursal fluid (n = 61), osseous irregularities of the GT (n = 118), and fatty atrophy GMin (n = 102) were statistically associated with partial or complete GMin tendon tearing (p < 0.001).

CONCLUSIONS

The spectrum of GMin tendon pathology observed on MR imaging ranges from tendinopathy to complete tears. The majority of complete distal GMin tendon tears from the greater trochanter show continuity of distal tendon fibers with the proximal vastus lateralis, distally tethering and limiting proximal tendon retraction.

Multimodality imaging of greater trochanter lesions

Purpose

Greater trochanter (GT) lesions are relatively uncommon. They can be traumatic, infective including tuber-culosis, inflammatory, and neoplastic (primary and metastatic osseous lesions). Although imaging of greater trochanter lesions remains essential for differential diagnoses, an image-guided biopsy is a mainstay for diagnosis and to guide subsequent management.

Material and methods

A retrospective search for the word ‘greater trochanter’ was performed of a computerised radiology information system (CRIS) of a tertiary referral centre for orthopaedic oncology over a period of 12 years (2007-2019). This revealed 6019 reports with 101 neoplasms. The imaging, histology, and demography were reviewed by a dedicated musculoskeletal radiologist.

Results

We identified 101 GT neoplasms with a mean age of 51.5 years (range 6 to 85 years) and a slight female predominance of 1.2 : 1 (46 males and 55 females). Using 30 years of age as a cut-off, we further segregated the patient cohort into 2 groups: 26 (25.74%) lesions in patients less than 30 years age and the remaining 75 (74.26%) lesions in patients over 30 years old. Chondroblastoma was the most common neoplasm in patients below 30 years of age, and metastases were the most common neoplasms in patients over 30 years of age.

Conclusions

Greater trochanter pathologies show a broad spectrum of aetiologies. Imaging including radiographs, computed tomography, magnetic resonance imaging, and nuclear medicine scans help to narrow down the differen-tials diagnosis.

MR of tendons about the hip: A study in asymptomatic volunteers

PURPOSE

Tendon pathology around the hip is a common entity. The aim of this study was to detect tendon abnormalities around the hip in a population of asymptomatic volunteers.

MATERIALS AND METHODS

Fifty volunteers (100 hips) referred for non-musculoskeletal conditions were evaluated with an additional coronal STIR-weighted MRI imaging on a 1.5 MR unit. This group was composed of 27 women and 23 men with a mean age of 52 (19-91 years). The images were interpreted independently by 2 musculoskeletal radiologists. All tendons around the hip were given a score from 0 to 4, with a score 0 corresponding to no abnormality, score 1 to signal alteration around the tendon, score 2 to minimal signal abnormality in the tendon, score 3 partial tear and score 4 complete rupture. The trochanteric bursa was also evaluated and its size was measured. It was also given a score from 0 to 3 (0: no abnormality, 1: slight hypersignal, 2: bursitis < 10 mm, 3: bursitis ≥ 10 mm).

RESULTS

High intratendinous signal was commonly found at the joined insertion of biceps femoris and semitendinosus (18% L, 20% R), the semimembranosus (24% L, 20% R), gluteus minimus (6% L, 11% R) and rectus femoris (9% L, 3% R). A small trochanteric bursa was seen in 33% of the volunteers on the left side and 32% on the right side. The interobserver correlation was very good with an intraclass correlation coefficient of 0.79 (CI: 0.74-0.85).

CONCLUSION

Slight signal alterations might be found in the insertions of the rectus femoris, hamstrings and gluteus minimus tendons. A small to moderate trochanteric bursitis might also be seen. This suggests that care should be taken when interpreting MR scans to attribute symptoms to these findings.

[Avulsion injuries of the gluteus medius and gluteus minimus muscles]

Avulsion injuries of the gluteus medius and gluteus minimus muscles represent a diagnostic and therapeutic challenge. Such injuries are rarely to be expected in high-energy trauma. Degenerative damage or iatrogenic injuries in the context of hip surgery are more frequently identified as the cause. Clinically, in addition to lateral hip pain, limping is an important finding and depends on the extent of the tendon damage. In addition to the medical history and clinical examination, imaging by means of sonography and, above all, magnetic resonance imaging (MRI, possibly with artifact-reduced sequences in the presence of an endoprosthesis) are diagnostically groundbreaking. Therapeutically, a stepwise approach is indicated according to the extent of rupture and quality of the gluteal tendon and muscle tissues. Specific conservative training regimens, mini-open/endoscopic anatomic reconstruction techniques in cases of gluteal muscle integrity and muscle transfer techniques as salvage option with chronic mass ruptures are available. The common goal is the restoration of everyday occupational and private activities to regain the quality of life.

[Inflammatory changes of the hip joint]

Die Osteoarthrose ist die häufigste Ursache für den Hüftschmerz des Erwachsenen. Daher wird anderen Ursachen wie z. B. Entzündungen weniger Beachtung für den Gelenkschmerz in der Erstdiagnose geschenkt. Dieser Artikel gibt eine Übersicht von unterschiedlichen rheumatologischen Erkrankungen der Hüfte und deren Interpretation in der Bildgebung. Die Vor- und Nachteile der einzelnen bildgebenden Verfahren werden anhand der pathologischen Befunde für die rheumatologischen Erkrankungen erläutert.

Hip Imaging and Injections

Athletic injuries of the hip often require radiographs and advanced imaging for diagnosis. Plain radiographs evaluate for osseous injury, provide a structural context behind an athlete's symptoms and examination, and offer a backdrop for interpretation of advanced imaging. An understanding of normal anatomy, imaging findings, and radiographic measurements allows for recognition of pathoanatomy and ability to diagnose accurately. Advanced imaging modalities, including magnetic resonance imaging, computed tomography, and ultrasonography, each play a role in evaluation of the athlete's hip. Although MRI and CT provide high-resolution imaging of the hip, ultrasonography offers the unique ability to perform dynamic imaging and guided injections.

Pathogenesis and contemporary diagnoses for lateral hip pain: a scoping review

PURPOSE

Recent advances in diagnostic imaging techniques and soft tissue endoscopy now allow for precise diagnosis and management of extra-articular hip pathology. The aim of this scoping review is to present an evidence-based update of the relevant literature focussing only on the pathoanatomy, clinical assessment and the diagnosis of pathology in the peritrochanteric space.

METHODS

A literature search was performed on PubMed to include articles which reported on the anatomy and diagnosis of greater trochanteric pain syndrome, trochanteric bursitis, gluteus medius tears and external snapping hip syndrome.

RESULTS

A total of 542 studies were identified, of which 49 articles were included for full text analysis for the scoping review. Peritrochanteric space pathology can be broadly classified into (1) greater trochanteric pain syndrome (GTPS), (2) abductor tears and (3) external snapping hip syndrome. Anatomically, gluteus medius, gluteus minimus and tensor fascia lata work in conjunction to abduct and internally rotate the hip. The anterolateral part of the gluteus medius tendon is more prone to tears due to a thin tendinous portion. Increased acetabular anteversion has also been shown to be associated with gluteal and trochanteric bursitis. In terms of clinical examination, tests which were found to be most useful for assisting in the diagnoses of lateral hip pain were the single-leg stance, resisted external derotation of the hip, hip lag sign and the Trendelenburg's test. Dynamic ultrasound along with guided injections and MRI scan do assist in differentiating the pathology and confirming the diagnosis in patients presenting with lateral hip pain. Finally, the assessment of baseline psychological impairment is essential in this group of patients to ensure outcomes are optimised.

CONCLUSION

Lateral hip pain used to be a poorly defined entity, but advances in imaging and interest in sports medicine have led to a better understanding of the pathology, presentation and management of this cohort of patients. A thorough appreciation of the anatomy of the abductor musculature, specific clinical signs and imaging findings will lead to an appropriate diagnosis being made and management plan instituted.

LEVEL OF EVIDENCE

IV.

The pathological features of hip abductor tendon tears - a cadaveric study

Background

The hip abductors are crucial in maintaining pelvic stability. Tears in these tendons are common and often debilitating. There is uncertainty regarding both the histological and macroscopic features of hip abductor tears. This study aims to clarify both the macroscopic and microscopic features of the tendon and enthesis in hip abductor tendon tears.

Methods

Thirty-six cadavers with an average age of 81 were dissected, and the hip abductor mechanisms removed en-bloc. The presence, location and size of the tears were recorded and analysed. The samples were processed into histological blocks and viewed using both transmitted and polarised light. Tendon histology was graded using the modified Movin’s score in three sections (deep, middle and superficial layers) and the enthesis graded separately using 5-point criteria. Analysis of variance was used to confirm histological features associated with tears.

Results

Tears were found in 24 of 36 samples (67%). The most common finding was an isolated tear in the gluteus minimus (46%), followed by concurrent gluteus medius and gluteus minimus tears (33%). Histology revealed significantly more degeneration in both the tendon (p = 0.0005) and enthesis (p = 0.0011) when tears were present. Furthermore, these changes were concentrated in the deeper layers of the tendon (p = 0.0002) and enthesis (p = 0.003).

Conclusion

This study demonstrated degeneration as the primary pathology underlying hip abductor tendon tears. Degenerative changes occur in both the tendon and enthesis, with the deeper layers predominantly affected. These findings are important for guiding surgical repair techniques and to aid the development of novel materials and biologics.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-020-03784-3.

Impact of fluoroscopic injection location on immediate and delayed pain relief in patients with greater trochanteric pain syndrome

OBJECT

The purpose of this study was to assess whether fluoroscopically guided corticosteroid injections into the extrabursal tissues, trochanteric (subgluteus maximus) bursa, or subgluteus medius bursa provide better immediate and short-term pain relief.

MATERIALS AND METHODS

All fluoroscopically guided corticosteroid injections performed over a 67-month period for greater trochanteric pain syndrome were retrospectively reviewed. Procedural images were reviewed by two musculoskeletal radiologists to determine the dominant injection site based on final needle positioning and contrast spread pattern, with discrepancies resolved by consensus. Statistical analysis of the association between pain score reduction and dominant injection site was performed.

RESULTS

One hundred forty injections in 121 patients met the inclusion criteria. The immediate and 1-week post-injection pain reduction was statistically significant for trochanteric bursa, subgluteus medius bursa, and non-bursal injections. However, there was no statistically significant difference in the degree of pain reduction between the groups. There was statistically significant increase in the 1-week post-injection mean pain score compared with immediate post-injection mean pain score in the subgluteus medius bursa and non-bursal injection groups (p < 0.01) but not in the trochanteric bursa group.

CONCLUSION

Fluoroscopy is frequently chosen over blind injection or ultrasound guidance for trochanteric steroid injections in patients with a high body mass index. Our results indicate that fluoroscopically guided steroid injections into the trochanteric bursa and subgluteus medius bursa significantly reduced immediate and 1-week post-injection pain scores, as do non-bursal injections. Steroid injection into the subgluteus medius bursa and non-bursal sites may be less effective in maintaining pain reduction at 1-week post-injection.

Clinical significance of the musculus gluteus minimus in total hip arthroplasty

Dislocation of the acetabular component is one of the most frequent complications of total hip arthroplasty. It is commonly attributed to implant malpositioning. However, not all dislocations can be explained by this hypothesis. The aim of our study was to elucidate the role of intraoperative injury to hip abductors (m. gluteus minimus in the first place, since it is reportedly an important hip stabilizer) in the development of postoperative hip dislocation. The experiment was conducted in 4 male and 3 female cadavers. A total of 12 THA were performed. The Hardinge and Watson-Jones approaches were used in equal proportion. On plain radiography, acetabular inclination was 40–47°, anteversion was 10–22°; technically and biomechanically, these values were within the normal range and did not depend on the type of surgical approach (for inclination, p = 0.94; for anteversion, p = 0.63), ruling out implant malpositioning as a risk factor for hip dislocation. Nevertheless, implant stability was significantly disrupted following transection of the anterior or posterior fascicle of m. gluteus minimus, leading to the dislocation of the acetabular component in standard rotation and flexion tests. Thus, our study shows the significant role of m. gluteus minimus in stabilizing the hip joint. Preservation or adequate repair of this muscle during surgery will reduce the risk or dislocation and help to restore the anatomy and biomechanics of the operated joint.

Magnetic resonance imaging of the hip: anatomy and pathology

The aim of this review is to outline the normal anatomy of the hip and to discuss common painful conditions of the hip that affect the general adult population. Hip pain is a common complaint with many different etiologies. In this review, hip pathologies are divided by location into osseous, intra-articular and extra-articular lesions. Magnetic resonance imaging (MRI) is the modality of choice for investigating painful hip conditions due to its multiplanar capability and high contrast resolution. This review focuses on the characteristic MRI features of common traumatic and pathologic conditions of the hip.

Hip abductor tendon tears: where are we now?

Hip abductor tendon tear is a difficult problem to manage. The hip abductor mechanism is made up of the gluteus medius and minimus muscles, both of which contribute to stabilising the pelvis through the gait cycle. Tears of these tendons are likely due to iatrogenic injury during arthroplasty and chronic degenerative tendinopathy. Ultrasound and magnetic resonance imaging have provided limited clues regarding the pattern of disease and further work is required to clarify both the macro and microscopic pattern of disease. While surgery has been attempted over the last 2 decades, the outcomes are variable and the lack of high-quality studies have limited the uptake of surgical repair. Hip abductor tendon tears share many features with rotator cuff tears, hence, innovations in surgical techniques, materials and biologics may apply to both pathologies.

Imaging of chronic male pelvic pain: what the abdominal imager should know

Chronic pelvic pain is an important but underrecognized cause of morbidity in men. While there is abundant literature discussing female pelvic pain and the diagnostic role of imaging, much less attention has been given to imaging of non-gynecologic causes of chronic pelvic pain. Chronic pelvic pain in men can be a challenge to diagnose as pain may arise from visceral, musculoskeletal, or neurovascular pathology. Imaging of the pelvic viscera has been covered in detail elsewhere in this edition and therefore will not be reviewed here. We will focus upon topics less familiar to the abdominal radiologist, including imaging of pelvic floor, musculoskeletal, and neurovascular pathology.

Dynamic ultrasound-guided trochanteric bursal injection

Injection of steroid and anesthetic into the greater trochanteric bursa is commonly performed for trochanteric bursitis, gluteus medius/minimus tendinopathy, or as a part of a barbotage procedure for gluteus medius or minimus calcific tendonosis. Trochanteric bursal injection is widely performed both with and without image guidance, and is typically viewed as low-difficulty; however optimum needle tip position can be challenging. We discuss a simple dynamic technique to aid the practitioner in optimal needle placement.

The effect of posterior capsule repair in total hip arthroplasty: a systematic review and meta-analysis

Background

Prior studies have compared the posterior capsule repair group in primary total hip arthroplasty by posterior approach with the control group without posterior capsule repair suggesting that the posterior capsule repair group had better clinical outcomes. However, it is still a controversy which treatment is more helpful for hip diseases. The purpose of our article is to obtain the postoperative outcomes between the 2 procedures.

Methods

We performed a systematic search by browsing the MEDLINE, EMBASE, Cochrane Library. There is no restriction on the date of publication. Before we submit our manuscript, we have re-searched the literatures again, including the articles which directly compared the postoperative outcomes of the 2 procedures.

Results

A total of 8 comparative studies were included in our meta-analysis. The posterior capsule repair group showed less dislocation rate, higher HHS, and even less postoperative bleeding volume. Meanwhile, there is no significant difference in ROM between 2 groups.

Conclusion

In conclusion, according to current evidences, repairing posterior capsule during primary THA may have better functional outcomes, less dislocation incidence, and less loss of blood.

Sonoanatomy and Pathology of the Gluteus Minimus Tendon

Gluteus minimus disorders are a potential source of greater trochanteric or anterior hip pain. Disorders of the gluteus minimus tendon most commonly occur in conjunction with gluteus medius tendon abnormalities but can also occur in isolation. Understanding the sonoanatomy of the gluteus minimus muscle-tendon unit is a prerequisite for recognizing and characterizing gluteus minimus tendon disorders, which, in turn, guides treatment for patients with greater trochanteric or anterior hip pain syndromes.

Gluteus medius muscle pathologies - A case series & pictorial review

Introduction

Gluteus medius lesions are rare and can present with lateral hip pain. We present a spectrum of pathologies involving the gluteus medius and discuss the imaging features.

Material and methods

A search of our oncology database at tertiary orthopaedic oncology service was performed. The imaging features of these were analysed.

Results

There were nine cases involving the gluteus medius, which included soft tissue sarcomas, lipomas, infection and trauma with an average age of 62 years.

Conclusion

Gluteus medius lesions are rare and one should be aware of these as these can present as lateral hip pain.

Glossary of terms for musculoskeletal radiology

Members of the International Skeletal Society compiled a glossary of terms for musculoskeletal radiology. The authors also represent national radiology or pathology societies in Asia, Australia, Europe, and the USA. We provide brief descriptions of musculoskeletal structures, disease processes, and syndromes and address their imaging features. Given the abundance of musculoskeletal disorders and derangements, we chose to omit most terms relating to neoplasm, spine, intervention, and pediatrics. Consensus agreement was obtained from 19 musculoskeletal radiology societies worldwide.

Variation in greater trochanteric lateroversion: a risk factor for femoral stem varus in total hip arthroplasty

INTRODUCTION

Correct implant positioning is required to achieve adequate biomechanics. The greater trochanter is more medially or laterally positioned in some patients, known as trochanteric lateroversion. However, studies have not identified correlations between postoperative coronal alignment and variation in greater trochanteric lateroversion. The purpose of this study was to identify the effects of variation in greater trochanteric lateroversion on postoperative stem coronal alignment and to investigate other factors related to stem coronal alignment.

METHODS

A total of 213 hips in 149 patients who underwent total hip arthroplasty were included in this prospective study. The greater trochanters were categorised into 5 groups according to the degree of variation in greater trochanteric lateroversion, and the stem coronal alignment angle and stem fit were measured on anteroposterior radiographs.

RESULTS

Postoperative stem varus was positively correlated with greater trochanteric lateroversion (r = 0.26065, p = 0.0001) and negatively correlated with the stem fit (r = -0.16568, p = 0.0155).

DISCUSSION

Excessive variation in greater trochanteric lateroversion was a risk factor for femoral stem varus, and the stem varus position was always accompanied by inadequate canal filling. When the tip of the trochanteric overhang exceeded the centreline of the femoral canal, the influence of lateroversion of the greater trochanter on the femoral stem remarkably increased. Appropriate measures should be implemented to avoid a stem varus position and inappropriate stem fit.

Diagnostic accuracy of a new clinical test (resisted internal rotation) for detection of gluteus medius tears

The objective of this study was to evaluate the diagnostic accuracy of a new dynamic clinical examination for detection of gluteus medius (GM) tears. A case group of 50 patients undergoing arthroscopy with GM repair was compared with a control group of 50 patients undergoing arthroscopy who had no peritrochanteric symptoms. Both groups were examined clinically, had magnetic resonance imaging studies performed and underwent arthroscopic surgery. Recorded clinical examinations included abnormal gait (Trendelenburg), tenderness to palpation of the greater trochanter, resisted abduction and the test being studied, resisted internal rotation. For all clinical tests, the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy rates were calculated and compared with the arthroscopic and MRI data for the case group, and the MRI data for the control group. The resisted internal rotation test had a sensitivity of 92%, specificity of 85% and diagnostic accuracy of 88% in the detection of GM tears, with a low rate of false-positive and false-negative recordings. Other traditional clinical examination tests, with the exception of Trendelenburg gait, showed inferior rates. Trendelenburg gait had a higher specificity, but much lower sensitivity. The resisted internal rotation test aides in the detection of GM pathology. Due to the good results of the resisted internal rotation test in all the diagnostic parameters, we recommend incorporating it on the physical exam of patients with hip pain.

Sonographic assessment of the anatomy and common pathologies of clinically important bursae

High-resolution ultrasonography has many advantages in the imaging of the musculoskeletal system, when compared to other imaging methods, particularly in superficial, easily accessible parts of the body. It is a perfect diagnostic tool for visualizing the most common pathologies of the musculoskeletal system, including the bursae. Inflammation of bursae is frequent, and it can mimic other diseases of the musculoskeletal system. Therefore, knowledge of normal ultrasound anatomy of the bursae, their exact location in the human body, and the sonographic signs of their most common pathologies is essential for establishing a quick and accurate diagnosis by ultrasound. Common conditions affecting bursae, leading to bursitis, include acute trauma, overuse syndromes, degenerative diseases, inflammatory conditions (rheumatoid arthritis, psoriatic arthritis, gout etc.), infections such as tuberculosis, synovial tumors and tumor-like conditions (pigmented villonodular synovitis, osteochondromatosis), and many more. This review article presents and explains ultrasound examples of the most frequent pathological conditions affecting bursae. Images include normal and pathological conditions of bursae around the shoulder joint, elbow, hip, knee, and ankle joint.

Identification and differentiation of gluteus medius tendon pathology using ultrasound and magnetic resonance imaging

BACKGROUND

It has been suggested that imaging findings play a role in directing treatment for Greater Trochanteric Pain Syndrome. Structural diagnoses associated with Greater Trochanter Pain Syndrome include gluteal tendinosis, and partial- or full-thickness gluteal tendon tears. However, few studies have compared imaging to confirmed tendon pathology observed during surgery.

OBJECTIVE

To investigate the ability of magnetic resonance and ultrasound imaging to identify the presence of a pathological gluteus medius tendon in comparison to surgical and histological findings.

STUDY DESIGN

Cross-sectional study.

METHODS

26 participants undergoing gluteal tendon reconstruction surgery or hip arthroplasty were included. Prior to surgery, participants underwent both magnetic resonance (MR) (n = 23) and ultrasound (US) (n = 25) imaging. A radiologist (MR) and nuclear physicians (US) classified the gluteus medius tendon as normal, tendinosis (no tear), partial-thickness tear, or full-thickness tear.

RESULTS

Ultrasound identified 17 out of the 19 pathological gluteus medius tendons correctly. However, 5 of the 6 normal tendons were incorrectly identified as exhibiting pathology on ultrasound. Magnetic resonance rated 11 out of 17 pathological tendons as abnormal, with 4 out of 6 normal tendons identified correctly. Both imaging modalities were poor at identifying and differentiating between tendinosis and partial-thickness tears.

CONCLUSION

Both imaging modalities showed a reasonable ability to identify tendon pathology. While limited by sample size, these early findings suggest that both imaging modalities may be limited in identifying specific pathoanatomical diagnoses, such as partial-thickness tears. These limitations may misdirect treatment.

Single- Versus Double-Row Repair of Hip Abductor Tears: A Biomechanical Matched Cadaver Study

PURPOSE

The purposes of this study were (1) to evaluate the percentage of gluteus medius and minimus tendon footprint restoration that can be achieved with fixation using single-row repair versus double-row repair and (2) to evaluate the yield load of a repair of the gluteus medius and minimus tendon using single-row versus double-row repair techniques.

METHODS

Twelve human fresh-frozen cadaveric hip specimens (6 matched pairs, 4 female, mean age 47.5 ± 14.5 years) were tested. Specimens were excluded if they had any prior hip surgery or injury, if any abnormality of the tendon was noted on dissection, or if they had a body mass index <20 or >35 or a T-score <2.0 on dual-energy x-ray absorptiometry scanning. Matched pairs were randomized to receive either double-row repair with 2 standard suture anchors and 2 knotless anchor devices or a single-row repair with suture anchors only. The percentage of the footprint area covered after repair was determined using a computer-assisted digitization algorithm. With a mechanical testing system, each repaired specimen was tested for mechanical strength first with cyclic loading and then load to failure testing.

RESULTS

Footprint coverage of the lateral facet was significantly greater for double-row repair (mean 76.6%) compared with single-row repair (mean 50.3%) (P = .03). There was no significant difference between single- and double-row repair for posterior-superior or anterior facet coverage. Mechanical testing showed a higher mean yield load for double-row anchor repair (197.6 ± 61.7 N vs 163.5 ± 35.4 N for single-row repair), but this did not reach statistical significance (P = .15). The predominant mode of failure was suture pullout through the musculotendinous unit (9/12 specimens: 5 double-row and 4 single-row).

CONCLUSIONS

For hip abductor tears, double-row suture repair yields improved footprint coverage compared with single-row repair. Although it did not reach statistical significance, there was a higher mean yield load in the double-row group.

CLINICAL RELEVANCE

Double-row suture fixation technique for hip abductor tears maximizes strength and footprint coverage of the repair.

The Gluteus Medius Tendon and Its Insertion Sites: An Anatomical Study with Possible Implications for Gluteus Medius Tears

BACKGROUND

Gluteus medius tears are a common hip disorder. Despite this, the etiology of these tears and the anatomical background of the gluteus medius tendon remain unclear. This study aimed to clarify the characteristics of the gluteus medius tendon. We hypothesized that the tendinous portions of the gluteus medius have a nonuniform structure contributing to the tear etiology.

METHODS

Twenty-five hips from 15 Japanese cadavers were analyzed. Twenty-one of the hips were analyzed macroscopically, and the other 4 were analyzed histologically. In all of the specimens, the 3-dimensional (3D) morphology of the greater trochanter was examined using microcomputed tomography (micro-CT). In 10 of the 21 hips analyzed macroscopically, the local thickness of the gluteus medius tendon, detached from the greater trochanter, was measured.

RESULTS

The posterior and anterolateral parts of the gluteus medius tendons were roughly distinguished on the basis of the aspects of the iliac origins. The posterior part of the gluteus medius tendon ran in a fan-like shape and converged onto the superoposterior facet of the greater trochanter. The anterolateral part ran posteroinferiorly toward the lateral facet of the greater trochanter. The thickness was greater in the posterior part than in the anterolateral part, and the border between these 2 parts was relatively thin compared with the other parts. The histological study showed that both the posterior and anterolateral parts inserted onto the greater trochanter via fibrocartilage.

CONCLUSIONS

The gluteus medius tendon consists of thick posterior and thin anterolateral parts, which were identified by the facet or aspect of the bone structures and thinness of their border region.

CLINICAL RELEVANCE

Our findings indicate that, given the nonuniform structure of the gluteus medius tendon, the thin anterolateral part may be more prone to tears than the thick posterior part is and tears may generally be limited to the anterolateral part.

US Assessment of Sports-related Hip Injuries

Traumatic and overuse hip injuries occur frequently in amateur and professional athletes. After clinical assessment, imaging plays an important role in diagnosis and in defining care management of these injuries. Ultrasonography (US) is being increasingly used in assessment of hip injuries because of the wide availability of US machines, the lower cost, and the unique real-time imaging capability, which allows both static and dynamic evaluation as well as guidance of point-of-care interventions such as fluid aspiration and steroid injection. Accurate diagnosis of hip injuries is often challenging, given the complex soft-tissue anatomy of the hip and the wide spectrum of injuries that can occur. To conduct a skillful US evaluation of hip injuries, physicians must have pertinent knowledge of the normal anatomy and should make judicious use of surface anatomy landmarks while using a compartmentalized diagnostic approach. In this article, common sports-related injuries of the anterior, lateral, and posterior hip compartments are discussed. This review includes assessment of joint effusion, acetabular labral tear, acute and chronic tendon injuries including tendinopathy, partial and full-thickness tears, snapping hip syndromes, relevant US-guided procedures, and some other conditions such as Morel-Lavallée lesion and perineal nodular induration. Principles of care management and current knowledge on imaging findings that may affect return to activity are also presented. Using an oriented US examination technique and having knowledge of the normal hip anatomy will help physicians characterize US findings of common sports-related hip injuries and make accurate diagnoses. Online supplemental material is available for this article. ^©RSNA, 2018.

Long-term outcome of low-energy extracorporeal shockwave therapy on gluteal tendinopathy documented by magnetic resonance imaging

Background

Previous outcome studies for extracorporeal shock wave therapy (ESWT) have included clinically diagnosed greater trochanteric pain syndrome (GTPS). The purpose of this study is to investigate outcome of ESWT on GTPS with gluteal tendinopathy documented by magnetic resonance imaging (MRI).

Methods

Medical records of 38 consecutive patients were retrospectively reviewed, who underwent ESWT for GTPS with MRI-documented gluteal tendinopathy (> 6 months). ESWT was conducted (1/week) when the Roles-Maudsley score (RMS) showed “Poor” or “Fair” grade after conservative treatment until RMS had reached “Good” or “Excellent” grade (treatment success) or until 12 treatments had been applied. Numeric rating scale (NRS) and RMS were evaluated before, 1 week after (immediate follow-up) and mean 27 months after ESWT program (long-term follow-up). Success rate was calculated at each follow-up point.

Results

Initial NRS (5.9 ± 1.6) significantly decreased at immediate (2.5 ± 1.5, p< 0.01) and long-term follow-up (3.3 ± 3.0, p< 0.01), respectively. Success rates were 83.3% (immediate) and 55.6% (long-term), respectively. There was no correlation among age, symptom duration and NRS.

Conclusion

Low-energy ESWT can be an effective treatment for pain relief in chronic GTPS with MRI-documented gluteal tendinopathy. However, its long-term effect appears to decrease with time.

Position of the greater trochanter and functional femoral antetorsion: Which factors matter in the management of femoral antetorsion disorders?

Aims

The primary aim of this study was to define and quantify three new measurements to indicate the position of the greater trochanter. Secondary aims were to define 'functional antetorsion' as it relates to abductor function in populations both with and without torsional abnormality.

Patients and Methods

Three new measurements, functional antetorsion, posterior tilt, and posterior translation of the greater trochanter, were assessed from 61 CT scans of cadaveric femurs, and their reliability determined. These measurements and their relationships were also evaluated in three groups of patients: a control group (n = 22), a 'high-antetorsion' group (n = 22) and a 'low-antetorsion' group (n = 10).

Results

In the cadaver group, the mean anatomical antetorsion was 14.7° (sd 8.5; 0 to 36.5) and the functional antetorsion 21.5° (sd 8.1; 3.6 to 44.3): the posterior tilt was 73.3° (sd 10.8; 46.9 to 88.7) and the posterior translation 0.59 (sd 0.2; 0.2 to 0.9). These measurements had excellent intra and interobserver agreement with a range from 0.93 to 0.99. When the anatomical antetorsion decreased, the greater trochanter was more tilted and translated posteriorly in relation to the axis of the femoral neck, and the difference between functional and anatomical antetorsion increased. The results the three patient groups were similar to those of the cadaver group.

Conclusion

The position of the greater trochanter and functional antetorsion varied with anatomical antetorsion. In the surgical management of femoral retrotorsion, subtrochanteric osteotomy can result in an excessively posterior position of the greater trochanter and an increase in functional antetorsion. Cite this article: Bone Joint J 2018;100-B:712-19.

Outcomes and cost-effectiveness of ultrasound-guided injection of the trochanteric bursa

We hypothesized that ultrasound (US) guidance improves outcomes of corticosteroid injection of trochanteric bursitis. 40 patients with greater trochanteric pain syndrome defined by pain to palpation over the trochanteric bursa were randomized to injection with 5 ml of 1% lidocaine and 80 mg of methylprednisolone using (1) conventional anatomic landmark palpation guidance or (2) US guidance. Procedural pain (Visual Analogue Pain Scale), pain at outcome (2 weeks and 6 months), therapeutic duration, time-to-next intervention, and costs were determined. There were no complications in either group. Ultrasonography demonstrated that at least a 2-in (50.8 mm) needle was required to consistently reach the trochanteric bursa. Pain scores were similar at 2 weeks: US: 1.3 ± 1.9 cm; landmark: 2.2 ± 2.5 cm, 95% CI of difference: - 0.7 < 0.9 < 2.5, p = 0.14. At 6 months, US was superior: US: 3.9 ± 2.0 cm; landmark: 5.5 ± 2.6 cm, 95% CI of difference: 0.8 < 1.6 < 2.4, p = 0.036. However, therapeutic duration (US 4.7 ± 1.4 months; landmark 4.1 ± 2.9 months, 95% CI of difference - 2.2 < - 0.6 < 1.0, p = 0.48), and time-to-next intervention (US 8.7 ± 2.9 months; landmark 8.3 ± 3.8 months, 95% CI of difference - 2.8 < - 0.4 < 2.0, p = 0.62) were similar. Costs/patient/year was 43% greater with US (US $297 ± 99, landmark $207 ± 95; p = 0.017). US-guided and anatomic landmark injection of the trochanteric bursa have similar 2-week and 6-month outcomes; however, US guidance is considerably more expensive and less cost-effective. Anatomic landmark-guided injection remains the method of choice, but should be routinely performed using a sufficiently long needle [at least a 2 in (50.8 mm)]. US guidance should be reserved for extreme obesity or injection failure.

Ultrasound Diagnostic and Therapeutic Injections of the Hip and Groin

Hip and groin pain often presents a diagnostic and therapeutic challenge. The differential diagnosis is extensive, comprising intra-articular and extra-articular pathology and referred pain from lumbar spine, knee and elsewhere in the pelvis. Various ultrasound-guided techniques have been described in the hip and groin region for diagnostic and therapeutic purposes. Ultrasound has many advantages over other imaging modalities, including portability, lack of ionising radiation and real-time visualisation of soft tissues and neurovascular structures. Many studies have demonstrated the safety, accuracy and efficacy of ultrasound-guided techniques, although there is lack of standardisation regarding the injectates used and long-term benefit remains uncertain.

Sports Injuries about the Hip: What the Radiologist Should Know

Injuries of the hip and surrounding structures represent a complex and commonly encountered scenario in athletes, with improper diagnosis serving as a cause of delayed return to play or progression to a more serious injury. As such, radiologists play an essential role in guiding management of athletic injuries. Familiarity with hip anatomy and the advantages and limitations of various imaging modalities is of paramount importance for accurate and timely diagnosis. Magnetic resonance (MR) imaging is often the modality of choice for evaluating many of the injuries discussed, although preliminary evaluation with conventional radiography and use of other imaging modalities such as ultrasonography (US), computed tomography, and bone scintigraphy may be supplementary or preferred in certain situations. Stress fractures, thigh splints, and posterior hip dislocations are important structural injuries to consider in the athlete, initially imaged with radiographs and often best diagnosed with MR imaging. Apophyseal injuries are particularly important to consider in young athletes and may be acute or related to chronic repetitive microtrauma. Femoroacetabular impingement has been implicated in development of labral tears and cartilage abnormalities. Tear of the ligamentum teres is now recognized as a potential cause of hip pain and instability, best evaluated with MR arthrography. Greater trochanteric pain syndrome encompasses a group of conditions leading to lateral hip pain, with US playing an increasingly important role for both evaluation and image-guided treatment. Muscle injuries and athletic pubalgia are common in athletes. Lastly, snapping hip syndrome and Morel-Lavallée lesions are two less common but nonetheless important considerations. ^©RSNA, 2016.

Sonoanatomy and Pathology of the Posterior Band of the Gluteus Medius Tendon

Greater trochanteric pain syndrome is a common clinical entity that most often results from disorders of the gluteus medius tendon. There are two distinct bands of the gluteus medius tendon, and abnormalities may affect the anterior or posterior band in isolation or simultaneously. Although abnormalities of the anterior band are more common, awareness and sonographic detection of posterior band abnormalities is essential to guide treatment in the setting of greater trochanteric pain syndrome.

Greater trochanter location measurement using a three-dimensional motion capture system during prone hip extension

[Purpose] The greater trochanter (GT) is an important structure in biomedical research, but the measurement methods require development. This study presents data from a new measurement method that does not use GT-marker-based measurement (No GT-m) in comparison with GT-marker based measurement (GT-m). [Subjects and Methods] We recruited 20 healthy subjects, who were asked to perform and maintain a prone position and then move to the prone hip extension. A motion capture system collected the kinematic data and the location of the GT was calculated by two measurements. [Results] GT migration distance differed significantly between the two measurements and the coefficient of the variation value was lower for the No GT-m method. Thigh lengths of the No GT-m method were comparable to the original lengths. There were significant differences between the GT-m and the other methods. [Conclusions] These data suggest that the GT-m method yielded a lower precision with a smaller GT migration distance. In the comparison of thigh length, the No GT-m method was in close agreement with the original length. We suggest that determining the location of the GT using the No GT-m has greater accuracy than the GT-m method.

Pain, not structural impairments may explain activity limitations in people with gluteal tendinopathy or hip osteoarthritis: A cross sectional study

QUESTION

What are the functional differences between people with greater trochanteric pain syndrome (GT), hip osteoarthritis (OA) or an asymptomatic population as measured by walking, Time Up and Go, single leg standing and strength?

DESIGN

Cross sectional study with blinded measurers.

PARTICIPANTS

38 participants with GT, 20 with end stage hip OA and 21 asymptomatic healthy control (AS) participants. All participants were women.

OUTCOME MEASURES

Pain (numeric rating scale), Walking speed (m/s), cadence (steps/min) and step length (m) measured via the 10m walk test and the Timed Up and Go; balance via single leg stance (s) duration; and hip abduction, adduction, medial and lateral rotation strength, standardized to body mass (BM) via the body mass average index (BMavg), measured via a wall mounted dynamometer.

RESULTS

The two symptomatic groups reported similar pain levels (p=0.226), more pain then the AS group (p<0.000). Compared to the AS participants, participants with GT or hip OA demonstrated lower walking speed (10mwt and TUG, p<0.001), lower cadence and shorter duration single leg stance on the affected leg (p<0.05). Participants with GT or hip OA also demonstrated bilaterally weaker hip abduction than the AS group (p≤0.005). Compared to AS and GT participants, participants with hip OA demonstrated adduction weakness on the affected side (p=0.008 and p=0.002 respectively).

CONCLUSION

There is a significant level of dysfunction and impairments associated with GT and hip OA. As activity limitations do not appear to be differentiated by structural impairments, we suggest that pain, rather than the underlying pathology may be the driving impairment that leads to walking and single leg standing dysfunction.

Greater Trochanteric Pain Syndrome: Percutaneous Tendon Fenestration Versus Platelet-Rich Plasma Injection for Treatment of Gluteal Tendinosis

OBJECTIVES

The purpose of this study was to compare ultrasound-guided percutaneous tendon fenestration to platelet-rich plasma (PRP) injection for treatment of greater trochanteric pain syndrome.

METHODS

After Institutional Review Board approval was obtained, patients with symptoms of greater trochanteric pain syndrome and ultrasound findings of gluteal tendinosis or a partial tear (<50% depth) were blinded and treated with ultrasound-guided fenestration or autologous PRP injection of the abnormal tendon. Pain scores were recorded at baseline, week 1, and week 2 after treatment. Retrospective clinic record review assessed patient symptoms.

RESULTS

The study group consisted of 30 patients (24 female), of whom 50% were treated with fenestration and 50% were treated with PRP. The gluteus medius was treated in 73% and 67% in the fenestration and PRP groups, respectively. Tendinosis was present in all patients. In the fenestration group, mean pain scores were 32.4 at baseline, 16.8 at time point 1, and 15.2 at time point 2. In the PRP group, mean pain scores were 31.4 at baseline, 25.5 at time point 1, and 19.4 at time point 2. Retrospective follow-up showed significant pain score improvement from baseline to time points 1 and 2 (P< .0001) but no difference between treatment groups (P= .1623). There was 71% and 79% improvement at 92 days (mean) in the fenestration and PRP groups, respectively, with no significant difference between the treatments (P >.99).

CONCLUSIONS

Our study shows that both ultrasound-guided tendon fenestration and PRP injection are effective for treatment of gluteal tendinosis, showing symptom improvement in both treatment groups.

Beyond the greater trochanter: a pictorial review of the pelvic bursae

PURPOSE

Review the MRI appearance of different bursae located throughout the pelvis, including the pertinent osseous and musculotendinous anatomy.

MATERIALS AND METHODS

Bursae are potential spaces that reduce friction between opposed moving components which can become inflamed, clinically mimicking internal derangement.

RESULTS

This series illustrates the most common as well as lesser-known pelvic bursae. Common causes of bursitis including overuse, trauma, and infection are presented.

CONCLUSION

Multiple bursae are located throughout the pelvis. It is important for radiologists to recognize bursitis as a potential etiology of pain and be familiar with their anatomical locations in order to guide appropriate management.

Core Injuries Remote from the Pubic Symphysis

The core, or central musculoskeletal system of the torso, is essential for participating in sports and other physical activities. Core injuries are commonly encountered in athletes and active individuals. The importance of the midline pubic plate and rectus abdominis-adductor aponeurosis for core stability and function is discussed in the literature. This review article examines other important core injuries remote from the pubic symphysis, relevant clinical features, and preferred approaches to imaging. Several specific syndromes encountered in the core are reviewed. By protocoling imaging studies and identifying pathology, radiologists can add value to the clinical decision-making process and help guide therapeutic options.

Disorders of the Peritrochanteric and Deep Gluteal Space: New Frontiers for Arthroscopy

Arthroscopic techniques for the hip joint have evolved into endoscopic methods for extra-articular disorders. These endoscopic strategies provide a less invasive alternative to open procedures for traditionally recognized forms of pathology. Endoscopy has defined new disorders amenable to surgical correction and has redefined some of these existing disorders. The peritrochanteric and deep gluteal regions represent 2 of the most currently active areas of exploration. Peritrochanteric problems include trochanteric bursitis, full-thickness and partial-thickness tears of the abductors including the gluteus medius and minimus, and external coxa saltans (snapping iliotibial band). Deep gluteal disorders include piriformis syndrome, and other variations of deep gluteal syndrome, and ischiofemoral impingement. Each of these evolving areas is highlighted in this chapter.