MRI of quadratus femoris muscle tear: another cause of hip pain

Ischiofemoral impingement syndrome: A five-case series report

Gluteal pain is a frequent cause of medical attention in the daily clinical practice. It can be caused by multiple pathologies, being ischiofemoral impingement syndrome among those included in its differential diagnosis. Encompassed within the deep gluteal syndromes, this entity occurs as a consequence of the entrapment of the neuromuscular structures between the lesser femoral trochanter and the ischial tuberosity, causing pain in the root of the lower limb, with irradiation towards the thigh or the gluteal region and poor tolerance to deambulation and sedestation. The magnetic resonance imaging of the hip is fundamental for its diagnosis, and its management consists on medical treatment at onset. Despite not being a frequent diagnosis in the clinical practice in Rheumatology, keeping it in mind helps improving its prognosis by establishing an early and adequate treatment.

Dynamic ultrasound assessment of hip instability and anterior and posterior hip impingement

OBJECTIVE

In this technical report, we describe our protocol for the dynamic sonographic evaluation of the hip and assess reliability of the ultrasound assessment of hip microinstability.

MATERIALS AND METHODS

Our clinical experience with a standardized dynamic ultrasound of the hip performed in a series of 27 patients with imaging performed by an experienced musculoskeletal radiologist during physical examination by an orthopedic surgeon specializing in hip preservation is illustrated with clinical photographs and ultrasound images from volunteers and selected patients. Interrater reliability for the diagnosis of microinstability was calculated.

RESULTS

Dynamic ultrasound technique and findings of hip instability, femoroacetabular impingement, and ischiofemoral impingement with corresponding clinical photos showing the necessary physical examination maneuvers are described. Interrater agreement for the diagnosis of microinstability was substantial (κ 0.606 [0.221-0.991]).

CONCLUSION

At our institution, dynamic ultrasound of the hip during physical examination complements information gathered from static imaging by providing real-time correlation of symptoms with what is occurring anatomically.

Ischiofemoral impingement syndrome: a case report and review of literature

Introduction

The etiology of ischiofemoral impingement (IFI) syndrome, an unusual and uncommon form of hip pain, remains uncertain. Some patients demonstrate narrowing of the space between the ischial tuberosity and lesser trochanter from trauma or abnormal morphology of the quadratus femoris muscle. Combined clinical and imaging aid in the diagnosis.

Case report

A 32-year-old female presented with a 3 years history of pain over the lower aspect of the right buttock, aggravated by movements of the right hip, and partially relieved with rest and medications. The right hip showed extreme restriction of abduction and external rotation. MRI of the right hip showed reduced ischiofemoral space and quadratus femoris space when compared to the left hip. The patient underwent endoscopic resection of the right lesser trochanter, with no recurrence of pain at 2 years.

Conclusion

An unusual cause of hip pain, IFI syndrome, should be suspected when hip pain at extremes of movement is associated with signal abnormality of quadratus femoris muscle. Management is tailored to address the inciting factors that precipitated the IFI syndrome.

Ischiofemoral Impingement Syndrome: Effect of Morphological Variations on the Diagnosis

OBJECTIVE

The purpose of this study is to clarify which morphologic variations of the hip on MRI are associated with the development of ischiofemoral impingement.

METHODS

Hip MRIs of patients who have been referred to our department between 2016-2017 were retrospectively reviewed and assessed for pathological signal changes in the quadratus femoris muscle and ipsilateral hip or buttock pain. After assessment, ischial angle, inclination angle, ischiofemoral space, quadratus femoris space, intertuberous distances and femur neck angle, femoral torsion angle and knee angle were measured and compared in 37 hips of 20 patients and 56 hips of 28 age-gender matched control subjects.

RESULTS

There were statistically significant differences between the patient and control groups in all MRI parameters except for intertuberous distances (p<0.05). Quadratus femoris space (p<0.001) and ischiofemoral space (p<0.001) were significantly lower and femoral torsion angle (p=0.02), femur neck angle (p=0.001), ischial angle (p=0.01) and inclination angle (p=0.03) values were significantly higher in patients compared with the control group.

CONCLUSION

Decreased ischiofemoral space and quadratus femoris space, increased femoral torsion angle, femur neck angle, ischial angle and inclination angle are found to be associated with IFI on MRI. These pelvic anatomical variations may predispose to ischiofemoral impingement and should be kept in mind for patients with hip pain.

Kinematic MRI of ischiofemoral impingement

OBJECTIVE

To examine the effect of external hip rotation on ischiofemoral (IF) and quadratus femoris (QF) spaces using real-time kinematic MRI, with the hypothesis that hips with IF and QF space narrowing have distinct motion patterns compared with control hips.

MATERIALS AND METHODS

This prospective study was IRB-approved and complied with HIPAA guidelines. We recruited women (≥ 18 years) with and without ischiofemoral impingement to undergo kinematic MRI of the hips. A kinematic imaging protocol using T2-HASTE was performed beginning at maximal internal rotation followed by active external hip rotation. The duration of each acquisition was 30 s, providing 8 images/3 s. IF and QF spaces, and femoral metaphyseal and lesser trochanter centroid coordinates were measured on sequential images. Hips were classified as controls or narrowed based on IF and QF space thresholds and compared statistically throughout motion stages.

RESULTS

The cohort comprised 12 women (24 hips; 10 control and 14 narrowed hips) aged 58 ± 10 years. External rotation caused IF space reduction of 59% in narrowed hips versus 41% in control hips. QF space decreased 71% in narrowed hips versus 50% in control hips. IF and QF spaces differed significantly between groups only when external rotation exceeded the neutral position (P < 0.02 for both). The lesser trochanter terminated more posteriorly in narrowed hips compared with controls (P = 0.03).

CONCLUSIONS

Kinematic MRI during external hip rotation in women with narrowed and control hips reveals dynamic differences in IF and QF spaces and lesser trochanter terminal position.

Ischiofemoral Impingement Syndrome Secondary to Arteriovenous Malformation of the Quadratus Femoris: A Case Report

CASE

Ischiofemoral impingement syndrome (IFIS), an unusual presentation of hip pain, is frequently missed in clinical practice. We report a case of a 27-year-old man with complaints of gradual onset nonprogressive right gluteal pain with hip movement restriction for the past 5 years that was not relieved with conservative measures. Right hip magnetic resonance imaging revealed a vascular abnormality of the right quadratus femoris muscle suggestive of IFIS. This abnormal muscle was surgically excised, and its histologic evaluation was remarkable for an arteriovenous malformation.

CONCLUSION

The patient's longstanding symptomatic IFIS was ultimately attributed to a rare arteriovenous malformation of the quadratus femoris that resolved with surgical excision.

Treatment strategies for ischiofemoral impingement: a systematic review

PURPOSE

There has been relatively little information about the treatment for ischiofemoral impingement (IFI) because of its rarity as well as the uncertainty of diagnosis. The aim of this study was to provide the reader with the available treatment strategies and their related outcomes for IFI based on the best available evidence, whilst highlighting classically accepted ways of treatment as well as relatively new surgical and non-surgical techniques.

METHODS

A systematic review of the literature from Medline, Embase, AMED, Cochrane and Google Scholar was undertaken since inception to December 2017 following the PRISMA guidelines. Clinical outcome studies, prospective/retrospective case series and case reports that described the treatment outcome for IFI were included. Animal or cadaveric studies, trial protocols, diagnostic studies without any description of treatments, technical notes without any results, and review articles were excluded.

RESULTS

This systematic review found 17 relevant papers. No comparative studies were included in the final records for qualitative assessment, which means all the studies were case series and case reports. Eight studies (47.1%) utilised non-surgical treatment including injection and prolotherapy, followed by endoscopic surgery (5 studies, 29.4%) then open surgery (4 studies, 23.5%). Mean age of the participants was 41 years (11-72 years). The mean follow-up was 8.4 months distributed from 2 weeks to 2.3 years. No complications or adverse effects were found from the systematic review.

CONCLUSION

Several treatment strategies have been reported for IFI, and most of them have good short- to medium-term outcomes with a low rate of complications. However, there are no comparative studies to assess the superiority of one technique over another, thus further research with randomised controlled trials is required in this arena. This study explores the wide variety and categories of different treatments used for IFI to guide physicians and shed light on what can be done for this challenging cohort of patients.

LEVEL OF EVIDENCE

III.

Editorial Commentary: A-version to a Pain in the Butt-Structural and Dynamic Determinants of Posterior Hip Pain

Ischiofemoral impingement is becoming a more recognized source of buttock pain that occurs as the lesser trochanter of the femur approximates the lateral margin of the ischium. Abnormal bony structure and alignment of the hip joint and/or faulty dynamic movement patterns may decrease the ischiofemoral space and compress the structures that are found within the space, including the quadratus femoris, proximal hamstring tendons, and sciatic nerve. The ischiofemoral space is reduced by structural factors including an increase in femoral anteversion and femoral neck angle. Dynamic assessment of the hip region may include the Craig test and total rotational range of motion of the hip joint, as well as the ischiofemoral impingement test and the long-stride walking test. The combination of structural and dynamic assessment of the hip region may help determine the presence of ischiofemoral impingement and direct appropriate management of the condition.

Contact-Related Strain of Quadratus Femoris, Obturator Externus, and Inferior Gemellus in an Australian Football Player: A Case Report

CONTEXT

Muscle injuries of the hip stabilizers are considered rare in sport.

OBJECTIVE

This report presents a previously unreported case of a contact injury resulting in acute strain of quadratus femoris, obturator externus, and inferior gemellus in an amateur Australian rules football player.

DESIGN

Level 4-case report.

CASE PRESENTATION

A player was tackled ipsilateral to the injured leg, while in hip flexion in a lunged position. The case describes the diagnostic process, initial management, and return to play for this athlete.

RESULTS

Following rehabilitation, the player was able to return to sport at 8 weeks without ongoing issues.

CONCLUSIONS

A literature search for sports-related contact injuries to either muscle returned only one result. All other documented cases of injury to these muscle groups are confined to noncontact mechanisms or delayed presentations. Despite conventional teaching, the action of the deep external rotators of the hip appears to be positionally dependent. Knowledge of this type of injury and mechanism may be useful for future clinical reasoning and differential diagnosis in patients with this type of presentation.

Injuries of the obturator muscles in professional soccer players

PURPOSE

Obturator externus and internus muscular tears are uncommon injuries. Only a few case reports exist, mainly in high-level athletes. Our aim is to describe a series of obturator externus and internus muscular tears in professional soccer players.

METHODS

Injury data from four teams from the First Division of the Spanish Soccer League were collected over a total of four seasons. Any soccer player who sustained an injury to either the obturator externus or internus identified on magnetic resonance (MRI) was included. All injured players were treated non-operatively with a goal of returning to play as fast as possible.

RESULTS

Sixteen players sustained injuries to the obturator externus and internus during matches or training sessions. The main complaint was anterior hip pain with a physical examination showing pain during internal rotation or external rotation of the flexed hip. The MRI documented 12 muscular tears of the obturator externus, and 4 muscular tears of the obturator internus. All injuries were treated conservatively based on physical therapy, analgesic medications, and underwent a symptoms-based rehabilitation protocol. Mean return to play was 11.5  ±  8.8 days.

CONCLUSION

Although uncommon, tears of the obturator externus and internus occur in professional soccer players. The MRI scan was essential to the location, classification, and evaluation of the injury size. The clinical relevance of our investigation is based on the relatively benign prognosis of these injuries.

LEVEL OF EVIDENCE

IV.

Magnetic Resonance Imaging in Symptomatic Children With Hereditary Multiple Exostoses of the Hip

BACKGROUND

Magnetic resonance imaging (MRI) is useful in evaluating nontraumatic hip pain. It provides information about associated injuries like labral/chondral tears or ischiofemoral impingement (IFI). However, in hereditary multiple exostoses (HME) there has been no report about MRI findings in symptomatic children with hip involvement.

METHODS

Records of children with HME and hip osteochondromas, who had hip MRI/magnetic resonance arthrography, were reviewed. The presence of chondral lesions and labral tears, as well the presence of IFI, was recorded. IFI was defined as edema or fatty replacement/atrophy in the quadratus femoris muscle or decrease of the space for this muscle between the ischium and the proximal femur. The measurements used to determine the space included the ischiofemoral space, the quadratus femoris space, and the minimum ischiofemoral space (MIFS). All measurements were performed on axial T1-weighted images.

RESULTS

Ten children were included (4 males, 6 females). In 2 patients, MRI was unilateral, therefore a total of 18 hips were analyzed. The indication for MRI was hip pain. Mean age, when MRI was performed, was 11.7 years. Labral tears were found in 44% (8/18) and chondral lesions in 33% (6/18) of the hips. The mean ischiofemoral space was 17.2 mm (SD, 7.3), the mean quadratus femoris space was 14.9 mm (SD, 5.3), and the mean MIFS was of 12.8 mm (SD, 5.9). IFI was seen in 44% (8/18) of hips. Two patients had bilateral IFI. MIFS was <10 mm in all hips with IFI (8/8). Of these hips, 88% (7/8) had edema of the quadratus femoris muscle and 38% (3/8) had fatty replacement/atrophy in the muscle. Osteochondromas were seen in the lesser trochanter in all hips with IFI (8/8) and in the ischium in 50% of them (4/8).

CONCLUSIONS

In symptomatic children with HME of the hip, MRI is helpful in detecting the source of pain. A high percentage of these children have IFI and intra-articular lesions. These findings can play an important role in the indication and planning of the surgical approach.

LEVEL OF EVIDENCE

Level IV-diagnostic study.

Ischiofemoral impingement secondary to valgus intertrochanteric osteotomy: a case report

We report an unusual case of ischiofemoral impingement secondary to valgus intertrochanteric osteotomy. The osteotomy was performed for treatment of epiphysiolysis of the left femoral head.

Effect of dry needling on myofascial pain syndrome of the quadratus femoris: A case report

This case report describes a 40-year-old male who presented with posterior thigh pain managed unsuccessfully with massage therapy, chiropractic adjustments, and physical therapy. The diagnosis of myofascial pain syndrome (MPS) involving the quadratus femoris (QF) was purely clinical, based on palpatory findings and ruling out other conditions through deductive reasoning. This is potentially a first time report, describing the successful management of MPS of the QF with dry needling (DN) using a recently published DN grading system. Immediate improvements were noted in all the outcome measures after the first treatment, with complete pain-resolution maintained at a 4-month follow-up.

Ischiofemoral impingement: defining the lesser trochanter-ischial space

PURPOSE

The purpose of this study was to define changes in the ischial-lesser trochanteric space associated with medial and lateral hip rotation in neutral and 10° of extension and adduction.

METHODS

Twenty-five hip joints from 14 embalmed cadavers (7 males and 7 females) were used for this study. The pelvic region of each cadaver was skeletonized, and the hip capsule released distally. With the hip joint in 0° flexion-extension/abduction-adduction, the distance between the lesser trochanter and ischium was measured in: neutral rotation, 40° medial rotation, and 60° lateral rotation. A one-way ANOVA with post hoc analysis determined the difference in the ischiofemoral space in these three positions. An additional position was then tested by laterally rotating the femur with the hip joint positioned in 10° extension and adduction.

RESULTS

The average distance between the lesser trochanter and ischium was different (p < .0005) in neutral rotation, 40° medial rotation, and 60° lateral rotation at 2.8 cm (SD 1.1), 4.3 cm (SD 1.2), and 1.4 cm (SD 0.7), respectively. With the hip joint laterally rotated from a starting position of 10° extension and adduction, 21 of 25 (84 %) hips made contact between the lesser trochanter and ischium at an average position of 29° (SD 20) of lateral rotation.

CONCLUSIONS

The lesser trochanter is closest to the ischium in lateral rotation and is furthest away in medial rotation when the hip is in neutral flexion-extension/abduction-adduction. The lesser trochanter approximates the ischium when the hip is laterally rotated in 10° extension and adduction. The information gained through this investigation helps to define the pathomechanics associated with ischiofemoral impingement and validate clinical tests to diagnose ischiofemoral impingement.

Ischiofemoral impingement and hamstring dysfunction as a potential pain generator after ischial tuberosity apophyseal fracture non-union/malunion

PURPOSE

The purpose of this study was to describe the occurrence of ischiofemoral impingement (IFI) and hamstring dysfunction following malunion or non-union of ischial tuberosity apophyseal avulsion fractures and report the short-term outcomes of surgical treatment with regard to alleviating symptomatic extra-articular impingement.

METHODS

All patients who underwent surgery for recalcitrant hip and buttock pain in the setting of prior ischial tuberosity avulsion fracture at three tertiary-level hip preservation centres were included for this review. A total of ten patients met our inclusion criteria and underwent sciatic neurolysis, resection of the ischial tuberosity fragment and hamstring reattachment. Clinical outcomes scores were collected post-operatively including the Modified Harris Hip Score (mHHS) and the Hip Outcomes Score (HOS).

RESULTS

Ten patients with a mean age of 18 years (range 14-28) underwent surgery for symptomatic ischiofemoral impingement after ischial tuberosity avulsion fracture. At a mean of 2.2-year follow-up (range 1.7-3.5), the median post-operative mHHS was 89.7 (65.7-96.8) and HOS ADL and Sport subscales were 90 % or greater in all cases. Five patients (50 %) rated their hip as normal, and five patients (50 %) rated their hip as near normal.

CONCLUSION

Malunion or non-union following ischial tuberosity apophyseal fracture can lead to IFI and hamstring dysfunction. Clinically, the resultant pain and dysfunction is often chronic, and can be debilitating. In select cases, a reliable surgical technique is presented to improve hamstring function and correct ischiofemoral impingement in this setting with good-to-excellent outcomes in the majority of cases at short-term follow-up.

LEVEL OF EVIDENCE

IV.

A Rare Case of Quadratus Femoris Muscle Rupture After Yoga Exercises

We present a case of a female patient with left groin pain after intense yoga exercises. The patient presented abnormal pattern of gait with no swelling over the groin, thigh, or buttock. Magnetic resonance imaging demonstrated a tear of the quadratus femoris muscle with an associated extensive hematoma formation. Patient was treated with a rehabilitation program consisting of nonsteroidal anti-inflammatory drugs and physiotherapy. At the follow-up control, the patient had improved her pain and flexibility of the hip, and gradually she returned to daily activities and yoga exercises. Such an entity is a rare cause of hip pain after exercise and should be kept in mind by the orthopedic surgeon, in cases of gluteal pain after intense physical activity. Moreover, such a condition should be included in the diagnostic algorithm of unknown origin hip pain.

Can Ultrasound Accurately Assess Ischiofemoral Space Dimensions? A Validation Study

BACKGROUND

Ischiofemoral impingement is a potential cause of hip and buttock pain. It is evaluated commonly with magnetic resonance imaging (MRI). To our knowledge, no study previously has evaluated the ability of ultrasound to measure the ischiofemoral space (IFS) dimensions reliably.

OBJECTIVE

To determine whether ultrasound could accurately measure the IFS dimensions when compared with the gold standard imaging modality of MRI.

DESIGN

A methods comparison study.

SETTING

Sports medicine center within a tertiary-care institution.

PARTICIPANTS

A total of 5 male and 5 female asymptomatic adult subjects (age mean = 29.2 years, range = 23-35 years; body mass index mean = 23.5, range = 19.5-26.6) were recruited to participate in the study.

METHODS

Subjects were secured in a prone position on a MRI table with their hips in a neutral position. Their IFS dimensions were then acquired in a randomized order using diagnostic ultrasound and MRI.

MAIN OUTCOME MEASUREMENTS

The main outcome measurements were the IFS dimensions acquired with ultrasound and MRI.

RESULTS

The mean IFS dimensions measured with ultrasound was 29.5 mm (standard deviation [SD] 4.99 mm, standard error mean 1.12 mm), whereas those obtained with MRI were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). The mean difference between the ultrasound and MRI measurements was 1.25 mm, which was not statistically significant (SD 3.71 mm, standard error mean 3.71 mm, 95% confidence interval -0.49 mm to 2.98 mm, t₁₉ = 1.506, P = .15). The Bland-Altman analysis indicated that the 95% limits of agreement between the 2 measurement was -6.0 to 8.5 mm, indicating that there was no systematic bias between the ultrasound and MRI measurements.

CONCLUSIONS

Our findings suggest that the IFS measurements obtained with ultrasound are very similar to those obtained with MRI. Therefore, when evaluating individuals with suspected ischiofemoral impingement, one could consider using ultrasound to measure their IFS dimensions.

LEVEL OF EVIDENCE

III.

Defining the greater trochanter-ischial space: a potential source of extra-articular impingement in the posterior hip region

The purpose of this study was to describe greater trochanteric-ischial impingement and the relative position of the hip joint where impingement occurs. Twenty-three hips from 13 embalmed cadavers (seven males and six females) with a lifespan ranging between 46 and 91 years were used for this study. The pelvic region of each cadaver was skeletonized leaving only the hip capsule and the sciatic nerve. From 90° of flexion, the hip was extended while maintaining a position of 30° abduction and 60° external rotation. The position of hip flexion was recorded when there was contact between the greater trochanter and the ischium. The procedure was repeated in 0° abduction. A Flexion-Abduction-External Rotation (FABER) test was then performed on all specimens with a positive finding defined as contact between the greater trochanter and the ischium. In 30° abduction, contact of the ischium and the greater trochanter occurred in 87% (20/23) of the hips at an average of 47° of flexion (SD 10; range 20–60°). In 0° abduction, a positive finding was noted in 39% (9/23) of hips at an average of 59° flexion (SD 6; range 52–70°). A positive finding in the FABER test position was noted in 96% (22/23) of hips. The greater trochanter can impinge on the ischium when the hip is extended from 90° flexion in a 60° externally rotated position. This impingement occurred more commonly when the hip was in 30° abduction compared with neutral abduction. The FABER test position consistently created greater trochanteric–ischial impingement.

Evaluation and management of ischiofemoral impingement: a pathophysiologic, radiologic, and therapeutic approach to a complex diagnosis

Ischiofemoral impingement syndrome (IFI) is an underrecognized form of atypical, extra-articular hip impingement defined by hip pain related to narrowing of the space between the ischial tuberosity and the femur. The etiology of IFI is multifactorial and potential sources of ischiofemoral engagement include anatomic variants of the proximal femur or pelvis, functional disorders as hip instability, pelvic/spinal instability, or abductor/adductor imbalance, ischial tuberosity enthesopathies, trauma/overuse or extreme hip motion, iatrogenic conditions, tumors and other pathologies. Magnetic resonance imaging (MRI) is the diagnostic procedure of choice for assessing IFI and may substantially influence patient management. The injection test of the ischiofemoral space (IFS) has both a diagnostic and therapeutic function. Endoscopic decompression of the IFS appears useful in improving function and diminishing hip pain in patients with IFI but conservative treatment is always the first step in the treatment algorithm. Because of the ever-increasing use of advanced MRI techniques, the frequent response to conservative treatment, and the excellent outcomes of new endoscopic treatment, radiologists must be aware of factors that predispose or cause IFI. In addition, focused treatment in these conditions is often more important than in secondary impingement. In this article, we briefly describe the anatomy of the IFS, review the clinical examination and symptoms, assess the diagnostic imaging criteria and pathophysiological mechanisms, and develop an understandable classification of IFI, with particular focus on its etiology, predisposing factors, and associated musculoskeletal abnormalities. We also assess the role of the radiologist in the diagnosis, treatment, and preoperative evaluation of both primary and secondary IFI.

Supine Versus Standing Radiographs for Detecting Ischiofemoral Impingement: A Propensity Score-Matched Analysis

OBJECTIVE

The purpose of this study was to assess parameters of ischiofemoral impingement on supine and standing anteroposterior hip radiographs and to suggest optimal cutoff points for detection of ischiofemoral impingement.

MATERIALS AND METHODS

A retrospective study included patients with a clinical history of hip pain. All hip joints with evidence of quadratus femoris muscle edema on MR images were included in the ischiofemoral impingement patient group. An age- and sex-matched control group was derived from the same cohort by propensity score matching. On radiographs, two readers independently measured the following parameters: ischiofemoral space, quadratus femoris space, hamstring tendon area, ischiofemoral distance on supine radiograph, ischiofemoral distance on standing radiograph, and femoral neck-shaft angle. Group differences in parameters were assessed by Mann-Whitney U test. The intraclass correlation coefficient and the ROC AUC were obtained. Correlations between radiographic and MRI measures were assessed with Pearson correlation and Bland-Altman plot analyses. The Youden J index was used to select optimum cutoff points for each parameter.

RESULTS

There were 30 patients (44 hip joints; mean age, 54.8 ± 11 years) in the ischiofemoral impingement group and 88 patients (88 hip joints; mean age, 51.8 ± 13.4 years) in the control group. There were significant group differences in ischiofemoral space, quadratus femoris space, ischiofemoral distance on supine radiograph, ischiofemoral distance on standing radiograph, and neck-shaft angle (p < 0.05). Ischiofemoral distance on supine and standing radiographs exhibited good discriminative ability (AUC > 0.80). The optimal cutoff points for ischiofemoral distances on supine and standing radiographs were 19.9 and 19.1 mm for reader 1 and 21.1 and 17.0 mm for reader 2. Ischiofemoral space, quadratus femoris space, ischiofemoral distance on supine radiograph, and ischiofemoral distance on standing radiograph exhibited nearly perfect interobserver agreement (r > 0.8).

CONCLUSION

Ischiofemoral distances on supine and standing hip radiographs had good diagnostic performance and can be used as a screening tool, with optimal cutoff points.

The normal ischiofemoral distance and its variations

The aim of this study is to measure the ischiofemoral distance (IFD) in the normal hip with healthy surrounding soft tissues and describe its variations caused by gender, age and proximal femoral anatomy so that this could serve as a reference for future studies on this subject. This is a retrospective study in which we reviewed the CT scans of 149 patients (298 hips) who had a CT of their pelvis for non-orthopaedic (abdomino-pelvic) pathology. The images were reviewed by two independent observers and the IFD (the smallest distance between the lateral cortex of the ischial tuberosity and the posteromedial cortex of the lesser trochanter), offset (the perpendicular distance from the centre of the femoral head to a line running down the middle of the shaft of the femur) and the neck-shaft angle (the angle between the lines in the middle of the neck to the line forming the axis of the femoral shaft) were measured. The CT scans belonged to 71 males and 78 females (M: 48%, F: 52%), with an average age of 51  ± 19 years (range 18–92). The mean IFD was 18.6  ±  8 mm in the females and 23  ± 7 mm in the males and this difference was statistically significant (P <  0.001). The IFD increased by 1.06 mm for each 1 mm of offset and dropped by 0.09 mm with each year of age. However, the neck-shaft angle did not show any significant correlation with the IFD.

Quadratus femoris tear as an unusual cause of hip pain: a case report

PURPOSE

To show that quadratus femoris muscle partial or complete tear is an extremely rare if not underdiagnosed cause of hip pain.

METHODS

We present the case of a 75-year-old Caucasian woman with spontaneous non-traumatic quadratus femoris tear.

RESULTS

Computed Tomography showed quadratus femoris tear with occult underlying ischiofemoral impingement pathology.

CONCLUSIONS

Quadratus femoris muscle is a hip external rotator and adductor and is situated along the posterior aspect of the hip joint and its proximity of anatomy with other external rotators leads to diagnostic pitfalls for radiologists. Identification of the exact muscle tear will establish the diagnosis, guide the proper physical therapy and reliably inform the patient what to expect after treatment.

Ischiofemoral impingement due to a lipoma of the ischiofemoral space

Non-focal hip and groin pain can frequently be a diagnostic problem, particularly if it is related to uncommon causes such as ischiofemoral impingement. The vast majority of published cases of ischiofemoral impingement are caused by osseous changes of the ischiofemoral interval. We describe an unusual case of ischiofemoral impingement caused by an intermuscular lipoma. Surgical resection of the tumour and histology confirmed the lipomatous nature of the tumour, with subsequent resolution of symptoms. To the best of our knowledge, this is the first case of a lipoma causing ischiofemoral impingement described in the English literature and emphasises that impingement can occur on the basis of a soft tissue mass occupying the interval of otherwise normal osseous interval and boundaries.

Ischiofemoral Impingement Syndrome: A Case Report and a Review of Literature

Background

Ischiofemoral impingement syndrome is characterized by a hip pain associated with abnormalities in quadriceps femoris muscle and ipsilaterally reduced distance between the lesser trochanter and the ischium. Thus far, the congenital variant of this entity has been reported exclusively in women.

Case Report

We report a case of a 22-year old male with painful hips in whom on the basis of the imaging studies the constitutional variant of ischiofemoral impingement was diagnosed.

Conclusions

Ischiofemoral conflict should be taken into consideration in the differential diagnosis of hip pain, particularly among women, but also in patients with valgus hip deformity and other abnormalities leading to reduction of the space between femoral and ischial bones independent of gender.

Gluteal Tendinopathy: Integrating Pathomechanics and Clinical Features in Its Management

Synopsis Gluteal tendinopathy is now believed to be the primary local source of lateral hip pain, or greater trochanteric pain syndrome, previously referred to as trochanteric bursitis. This condition is prevalent, particularly among postmenopausal women, and has a considerable negative influence on quality of life. Improved prognosis and outcomes in the future for those with gluteal tendinopathy will be underpinned by advances in diagnostic testing, a clearer understanding of risk factors and comorbidities, and evidence-based management programs. High-quality studies that meet these requirements are still lacking. This clinical commentary provides direction to assist the clinician with assessment and management of the patient with gluteal tendinopathy, based on currently limited available evidence on this condition and the wider tendon literature and on the combined clinical experience of the authors. J Orthop Sports Phys Ther 2015;45(11):910-922. Epub 17 Sep 2015. doi:10.2519/jospt.2015.5829.

Variability of the Ischiofemoral Space Relative to Femur Position: An Ultrasound Study

BACKGROUND

Ischiofemoral impingement is caused by compression of the quadratus femoris muscle between the ischial tuberosity and lesser trochanter. The evaluation of ischiofemoral impingement includes radiologic studies to evaluate the ischiofemoral space dimensions. No prior study has evaluated the effect of femoral position on ischiofemoral space dimensions.

OBJECTIVE

To determine whether the dimensions of the ischiofemoral space vary with changes in femoral position.

DESIGN

Cross-sectional study.

SETTING

Academic institution.

PARTICIPANTS

Six male and four female subjects with no hip pain and no history of hip disorders or surgery were selected to participate in the study. The subjects' mean age was 31.5 years; mean height, 176.8 cm; mean weight, 70.2 kg; and mean body mass index, 23.6 kg/m(2).

METHODS

Ultrasound was used to measure the ischiofemoral space in bilateral gluteal regions of each volunteer. The volunteers underwent imaging in a prone position. The ischiofemoral space was measured with the femur in 9 different positions created through various combinations of frontal (15° abduction, neutral, and 15° adduction) and transverse (30° internal rotation, neutral, and 30° external rotation) plane hip motions.

MAIN OUTCOME MEASUREMENTS

The narrowest ischiofemoral interval, defined as the narrowest distance between the medial cortex of the lesser trochanter and the lateral cortex of the ischial tuberosity.

RESULTS

The anatomic landmarks used to measure the ischiofemoral space were easily identified in all subjects. The frontal plane main effect (F2,18 = 38.611) was statistically significant (P < .001), as was the transverse plane main effect (F2,18 = 82.452, P < .001). These findings indicated that there was a statistically significant difference in ischiofemoral space according to hip position in the frontal and transverse planes. The largest ischiofemoral space measurement occurred with the hip in abduction and internal rotation (51.8 mm; 95% confidence interval [CI], 49.2-54.5 mm), whereas hip adduction and external rotation resulted in the narrowest ischiofemoral space measurement (30.8 mm; 95% CI, 25.5-36.0 mm). The largest difference was between the adduction-external rotation and the abduction-internal rotation positions (mean difference = 21.1 mm; 95% CI, 13.7-28.5 mm; P < .001), and the smallest difference was between the adducted-neutral rotation and the abducted-external rotation positions (mean difference = 0.23 mm; 95% CI, -8.07-8.55 mm; P = .99).

CONCLUSIONS

Femoral position affects ischiofemoral space dimensions. The ischiofemoral space widens with abduction and internal rotation and narrows with adduction and external rotation, and thus femoral position should be considered when imaging and measuring the ischiofemoral space.

Primary functions of the quadratus femoris and obturator externus muscles indicated from lengths and moment arms measured in mobilized cadavers

BACKGROUND

The small muscles of the pelvis and hip are often implicated in painful conditions. Although the quadratus femoris and obturator externus are usually described as external rotators of the hip, little is known about how they change their lengths and moment arms during human movement. Therefore, more precise measurements defining the positions and directions for their maximal strength and stretch are needed to better describe their functions and guide the clinical approach to pain.

METHODS

Repeated measurements of the muscle lengths and range of motion were obtained using wires simulating dissected muscles on human cadaver hips. The lengths were measured at every 15° of flexion with and without maximal range of ab/adduction, rotation, and combinations of the two motions. Measurements were obtained from normal hips (n=3), and movement-lengthening relations were later differentiated into movement-moment arm relations.

FINDINGS

The quadratus femoris showed maximum lengthening by flexion, adduction or abduction, and internal rotation, with the largest moment arms observed for extension in the deduced force-length efficient range of 60-90° flexion. The obturator externus showed maximum lengthening by extension, abduction, and internal rotation, with the largest moment arms observed for flexion and adduction in the deduced force-length efficient range around the hip's neutral position.

INTERPRETATION

Our findings indicate that maximal strength of the quadratus femoris muscle will be delivered in a flexed position towards extension, while maximal strength of the obturator externus muscle will be delivered in an extended position towards flexion and adduction.

Using proximal hamstring tendons as a landmark for ultrasound- and CT-guided injections of ischiofemoral impingement

Ischiofemoral impingement has been reported in a number of cases as an association between hip pain and quadratus femoris MRI signal abnormality, with concurrent narrowing of the ischiofemoral space. While the literature has included much emphasis on the imaging characteristics useful in the diagnosis of this entity, information on treatment has been scant, with few case reports of surgical resection of the lesser trochanter and incomplete descriptions of steroid injection techniques. We report a case of ultrasound- and CT-guided steroid injection into the ischiofemoral space via the proximal hamstring tendons in a 57-year-old female who had imaging and clinical characteristics of ischiofemoral impingement. The technique is described as a safe alternative to other possible injection techniques.

Bilateral ischiofemoral impingement in a patient with hereditary multiple exostoses

The skeletal anatomy of the hip provides two main locations for impingement: abnormal contact between the acetabulum and femur (femoroacetabular impingement) or between the ischium and femur (ischiofemoral impingement). We report a case of bilateral ischiofemoral impingement in a patient with hereditary multiple exostoses. The association of exostoses and femoral metaphyseal widening resulted in the narrowing of the ischiofemoral spaces. Pain was improved on the left side by resection of the ischial exostosis.

An algorithmic approach to mechanical hip pain

BACKGROUND

As our understanding of hip pathology evolves, the focus is shifting toward earlier identification of hip pathology. Therefore, it is vitally important to elucidate intra-articular versus extra-articular pathology of hip pain in every step of the patient encounter: history, physical examination, and imaging.

QUESTIONS/PURPOSES

The objective was to address the following research questions: (1) Can an algorithmic approach to physical examination of a painful non-arthritic hip provide a more accurate diagnosis and improved treatment plan? (2) Does an anatomical layered concept of clinical diagnosis improve diagnostic accuracy? (3) What are the diagnostic tools necessary for the accurate application of a four-layer (osteochondral, inert, contractile, and neuromechanical) diagnosis?

METHODS

An unrestricted computerized search of MEDLINE was conducted. Different terms were used in various combinations.

RESULTS

An algorithmic approach to physical examination of a painful nonarthritic hip, including history, physical examination (specific tests), and advanced imaging allow for better interpretation of debilitating intra- and extra-articular disorders and their effect on core performance. Additionally, it improves our understanding as to how underlying abnormal joint mechanics may predispose the hip joint and the associated hemipelvis to asymmetric loads. These abnormal joint kinematics (layer I) can lead to cartilage and labral injury (layer II), as well as resultant injury to the musculotendinous (layer III) and neural structures (layer IV) about the hip joint and the hemipelvis. The layer concept is a systematic means of determining which structures about the hip are the source of hip pathology and how to best implement treatment.

CONCLUSIONS

A clear understanding of the differential diagnosis of hip pain through a detailed and systematic physical examination, diagnostic imaging assessment, and the interpretation of how mechanical factors can result in such a wide range of compensatory injury patterns about the hip can facilitate the diagnosis and treatment recommendations.

Ischiofemoral impingement: hip pain of infrequent cause

Hip pain is a frequent cause of medical attention in the daily clinical practice. Among the different causes included in the differential diagnosis we find ischiofemoral impingement, described initially in patients after joint replacement surgery, but later found in patients with no history of a causal disease.

Imaging of snapping phenomena

Snapping phenomena result from the sudden impingement between anatomical and/or heterotopical structures with subsequent abrupt movement and noise. Snaps are variously perceived by patients, from mild discomfort to significant pain requiring surgical management. Identifying the precise cause of snaps may be challenging when no abnormality is encountered on routinely performed static examinations. In this regard, dynamic imaging techniques have been developed over time, with various degrees of success. This review encompasses the main features of each imaging technique and proposes an overview of the main snapping phenomena in the musculoskeletal system.

Ischiofemoral impingement: evaluation with new MRI parameters and assessment of their reliability

OBJECTIVE

The aim of this study was to describe the magnetic resonance imaging (MRI) findings in patients with ischiofemoral impingement (IFI) and to evaluate the reliability of these MRI findings.

MATERIALS AND METHODS

Seventy hips of 50 patients with hip pain and quadratus femoris muscle (QFM) edema and 38 hips of 30 control cases were included in the study. The QFM edema and fatty replacement were assessed visually. Ischiofemoral space (IFS), quadratus femoris space (QFS), inclination angle (IA), hamstring tendon area (HTA), and total quadratus femoris muscle volume (TQFMV) measurements were performed independently by two musculoskeletal radiologists. The intra- and interobserver reliabilities were obtained for quantitative variables.

RESULTS

IFS, QFS, and TQFMV values of the patient group were significantly lower than those of controls (P < 0.001). HTA and IA measurements of the patient group were also significantly higher than in controls (P < 0.05). The QFM fatty replacement grades were significantly higher in the patient group than in the control group (P < 0.001). Inter- and intra-observer reliabilities were strong for all continuous variables.

CONCLUSION

Clinicians and radiologists should be aware of IFI in patients with hip or groin pain, and MRI should be obtained for the presence of the QFM edema/fatty replacement, narrowing of the IFS-QFS, and other features that may help in the clinical diagnosis of IFI for the proper diagnosis and treatment of the disease.

ISCHIOFEMORAL IMPINGEMENT - AN ETIOLOGY OF HIP PAIN: CASE REPORT

An association between hip pain and quadratus femoris muscle abnormality on magnetic resonance imaging (MRI) with concurrent narrowing of the ischiofemoral space has been reported in the recent literature. This raises the possibility that the muscle damage observed is due to ischiofemoral impingement. This diagnosis has been noted in middle-aged females either with or without a history of trauma or surgery, is a rarely described feature. We report here on a 31-year-old woman who presented with non-traumatic hip pain and evidence of narrowing of the ischiofemoral space and edema in the quadratus femoris. Nonsurgical treatment was administered, which relieved her hip pain. The diagnosis of ischiofemoral impingement should be considered in female patients complaining of hip pain without any other evident cause.

Ischiofemoral impingement

Femoroacetabular impingement is a well-documented cause of hip pain. There is, however, increasing evidence for the presence of a previously unrecognised impingement-type condition around the hip - ischiofemoral impingement. This is caused by abnormal contact between the lesser trochanter of the femur and the ischium, and presents as atypical groin and/or posterior buttock pain. The symptoms are gradual in onset and may be similar to those of iliopsoas tendonitis, hamstring injury or bursitis. The presence of ischiofemoral impingement may be indicated by pain caused by a combination of hip extension, adduction and external rotation. Magnetic resonance imaging demonstrates inflammation and oedema in the ischiofemoral space and quadratus femoris, and is distinct from an acute tear. To date this has only appeared in the specialist orthopaedic literature as a problem that has developed after total hip replacement, not in the unreplaced joint.

Femoroacetabular impingement

Femoroacetabular impingement (FAI) is a pathomechanical concept describing the early and painful contact of morphological changes of the hip joint, both on the acetabular, and femoral head sides. These can lead clinically to symptoms of hip and groin pain, and a limited range of motion with labral, chondral and bony lesions. Pincer impingement generally involves the acetabular side of the joint where there is excessive coverage of the acetabulum, which may be focal or more diffuse. There is linear contact of the acetabulum with the head/neck junction. Cam impingement involves the femoral head side of the joint where the head is associated with bony excrescences and is aspheric. The aspheric femoral head jams into the acetabulum. Imaging appearances are reviewed below. This type is evident in young males in the second and third decades. The main features of FAI are described.

Case report: imaging and surgical treatment of a snapping hip due to ischiofemoral impingement

An association between hip pain and quadratus femoris MRI abnormality with concurrent narrowing of the ischiofemoral space has been reported in a number of patients to date, raising the possibility that the muscular damage observed is due to ischiofemoral impingement. Possible impingement has been noted primarily in middle-aged females either with or without a history of trauma or surgery, and associated snapping of the hip is a rarely described feature. We report here on a 17-year-old girl who presented with post-traumatic hip pain; she later developed evidence of ischiofemoral narrowing and quadratus femoris edema on MRI in addition to an audible snapping. Surgical resection of the lesser trochanter was performed, relieving both her hip pain and the snapping. To our knowledge, this is the first reported case of non-iatrogenic ischiofemoral impingement with surgical confirmation. The diagnosis of ischiofemoral impingement should be considered in patients complaining of a snapping hip.

Anatomic and radiographic evaluation of the hip

The hip is a challenging joint to study is deeply located in the pelvis and surrounding by a large group of muscles with complex tendinous attachments. Our knowledge has recently increased together with the advent of new surgical techniques but further research is needed to better understand hip biomechanics and the relevance of some of radiological findings. Although recent techniques such as MR show anatomy exquisitely is essential to start with pelvis plain radiography for a good evaluation of bone structures and pelvis alignment. During this chapter we will be give a short overview of pelvis normal structures and some key points of MR and MR arthrography technique, because more detailed description is done on every specific chapter.

Differential atrophy of the postero-lateral hip musculature during prolonged bedrest and the influence of exercise countermeasures

As part of the 2nd Berlin BedRest Study (BBR2-2), we investigated the pattern of muscle atrophy of the postero-lateral hip and hamstring musculature during prolonged inactivity and the effectiveness of two exercise countermeasures. Twenty-four male subjects underwent 60 days of head-down tilt bedrest and were assigned to an inactive control (CTR), resistive vibration exercise (RVE), or resistive exercise alone (RE) group. Magnetic resonance imaging (MRI) of the hip and thigh was taken before, during, and at end of bedrest. Volume of posterolateral hip and hamstring musculature was calculated, and the rate of muscle atrophy and the effect of countermeasure exercises were examined. After 60 days of bedrest, the CTR group showed differential rates of muscle volume loss (F = 21.44; P ≤ 0.0001) with fastest losses seen in the semi-membranosus, quadratus femoris and biceps femoris long head followed by the gluteal and remaining hamstring musculature. Whole body vibration did not appear to have an additional effect above resistive exercise in preserving muscle volume. RE and RVE prevented and/or reduced muscle atrophy of the gluteal, semi-membranosus, and biceps femoris long head muscles. Some muscle volumes in the countermeasure groups displayed faster recovery times than the CTR group. Differential atrophy occurred in the postero-lateral hip musculature following a prolonged period of unloading. Short-duration high-load resistive exercise during bedrest reduced muscle atrophy in the mono-articular hip extensors and selected hamstring muscles. Future countermeasure design should consider including isolated resistive hamstring curls to target this muscle group and reduce the potential for development of muscle imbalances.

Persistent sciatica induced by quadratus femoris muscle tear and treated by surgical decompression: a case report

INTRODUCTION

Quadratus femoris tear is an uncommon injury, which is only rarely reported in the literature. In the majority of cases the correct diagnosis is delayed due to non-specific symptoms and signs. A magnetic resonance imaging scan is crucial in the differential diagnosis since injuries to contiguous soft tissues may present with similar symptoms. Presentation with sciatica is not reported in the few cases existing in the English literature and the reported treatment has always been conservative.

CASE PRESENTATION

We report here on a case of quadratus femoris tear in a 22-year-old Greek woman who presented with persistent sciatica. She was unresponsive to conservative measures and so was treated with surgical decompression.

CONCLUSION

The correct diagnosis of quadratus muscle tear is a challenge for physicians. The treatment is usually conservative, but in cases of persistent sciatica surgical decompression is an alternative option.