Iliopsoas musculotendinous unit

Hip pain is a common condition with many etiologies, and the workup often includes imaging. The iliopsoas musculotendinous unit is becoming more frequently recognized as the culprit for hip pain, partially due to the increase in athletic activity in the general population as well as to the increased demand in professional sports. Iliopsoas tendon injuries are also seen in the elderly population and documented as occurring following total hip replacement. Iliopsoas diseases, often overlooked as a cause of hip pain, include tendinosis, snapping tendon, bursitis, tears, and avulsion injuries. This article reviews the normal magnetic resonance imaging and sonographic anatomy of the iliopsoas musculotendinous unit and the imaging characteristics of diseases that involve the iliopsoas musculotendinous unit. We review the causes of a snapping hip and the role of sonography in evaluating and guiding treatment of the snapping iliopsoas tendon.     

Hip MR arthrography and femoroacetabular impingement

Hip pain is a common complaint among athletes of all ages. Advances in imaging and treatment are changing the paradigm of evaluation and management of hip pain. The role of abnormal femoral and acetabular morphology and lesions of the acetabular labrum and cartilage is increasingly recognized as being crucial in the development of degenerative change. In addition, femoroacetabular impingement is increasingly recognized as an etiologic factor in hip pain. This article discusses techniques of hip magnetic resonance (MR) arthrography, normal anatomy seen at hip MR arthrography, common intra-articular pathologies in patients with hip pain, and imaging findings of femoroacetabular impingement.     

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 [1]. 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 [1–3]. 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.     

New developments in hip imaging

The way the hip joint is imaged has changed in the past few years as a result of new discoveries in the biomechanics of the hip joint and the rapid developments in hip-preserving surgery. This review discusses technical advances made in the field of hip imaging, covering the roles of radiography, computed tomography, sonography and magnetic resonance (MR) imaging, as well as their limitations. New insight into anatomy and pathogenesis can be useful for the diagnosis of hip abnormalities and in treatment planning. While radiographs are the basis of any imaging of the hip, MR imaging is paramount in the evaluation and preoperative planning of patients suspected of having femoroacetabular impingement, especially when assessing geometrical deformities of the proximal femur. Damage patterns of labrum and cartilage in patients with femoroacetabular impingement are described, as well as new techniques of cartilage MR imaging that might allow the detection of cartilage degeneration before macroscopic defects are formed. Finally, new data on structural variants of the hip joint and pitfalls in imaging of the hip joint are reviewed. ? RSNA, 2012.     

Arthroscopic treatment of the painful "internal" snapping hip: results of a new endoscopic technique and imaging protocol

BACKGROUND: Traditional surgical treatment for a painful snapping iliopsoas tendon has been an open lengthening of the tendon. HYPOTHESIS: An endoscopic release will alleviate painful snapping of the tendon. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Six patients with painful snapping hips who had no pain relief after magnetic resonance arthrography, which included injection of bupivacaine into the hip joint, subsequently had an ultrasound evaluation of their iliopsoas tendons and an anesthetic injection into the psoas bursa. In all 6 patients, the injection relieved their hip pain, and in 4, real-time imaging demonstrated snapping of the tendon. All hips were evaluated with the 100-point Harris hip scoring system before and at 1.5, 3, 6, and 12 months after surgery. RESULTS: Preoperative hip scores averaged 58 points. After surgery, all patients had hip flexor weakness, used crutches for 5 weeks, and had 6-week scores that averaged 62 points. The patients continued to improve, and at 6 and 12 months, their scores averaged 90 and 96 points, respectively, and none had recurrence of their snapping or pain. CONCLUSION: Ultrasound-guided anesthetic injection of the psoas bursa is useful to confirm snapping of the iliopsoas tendon as the cause of a patient's hip pain. Endoscopic release of the tendon is a safe outpatient procedure that provides effective relief of the snapping and pain.     

Evaluation of the painful athletic hip: imaging options and imaging-guided injections

OBJECTIVE: This article reviews diagnostic imaging tests and injections that provide important information for clinical management of patients with sports-related hip pain. CONCLUSION: In the evaluation of sports-related hip symptoms, MR arthrography is often used to evaluate intraarticular pathology of the hip. The addition of short- and long-acting anesthetic agents with the MR arthrography injection adds additional information that can distinguish between symptomatic and asymptomatic imaging findings. Osseous abnormalities can be characterized with radiography, MRI, or CT. Ultrasound is important in the assessment of iliopsoas abnormalities, including tendon snapping, and to guide diagnostic anesthetic injection.     

Magnetic resonance imaging of the hip

Standard magnetic resonance imaging (MRI) as well as MR arthrography (MRA) have been important diagnostic tools to assess for a spectrum of clinical presentations related to the hip. MRA has allowed the radiologist to closely examine intracapsular structures such as the acetabular labrum. In this article, we provide a general review of soft tissue and osseous anatomy of hips, especially focusing on the MR appearances of the acetabular labrum and the osseous morphology of the greater trochanter and ischial tuberosity with their muscle and tendon attachments. In addition, current topics in recent literature will be discussed such as femoroacetabular impingement (FAI) and rotator cuff tears of the hip.     

Shoe rim and shoe buckle pseudotumor of the ankle in elite and professional figure skaters and snowboarders: MR imaging findings

Objective To review MR imaging of figure skaters and snowboarders presenting with painful soft-tissue swelling of the lateral supramalleolar region with a clinical provisional diagnosis of soft-tissue tumor.Design and patients MR imaging was prospectively reviewed by two sub-specialized musculoskeletal radiologists. The findings were correlated with a second clinical review and examination of the shoe wear. The patients were four female athletes undergoing heavy training regimes, ranging in age between 16 and 25 years. Two patients were elite figure skaters, and two were professional snowboarders. Three patients had unilateral masses with pain, and one patient presented with bilateral clinical findings.Results MR imaging showed subcutaneous, focal soft-tissue masses of the supramalleolar region in five ankles at the same level above the ankle joint. MR imaging prompted a second clinical review and correlation with the shoe wear. The MR imaging findings correlated to the level of the shoe rim or shoe buckle in all patients, confirming the suspected MR imaging diagnosis of an impingement syndrome. All four sportswomen were training excessively, ignoring safety advice regarding training duration, timing of breaks, and shoe wear rotation.Conclusion Ice skaters and snowboarders may present with persistent and disabling pain. On MR imaging, this corresponds to a focal soft-tissue abnormality, which may be due to subcutaneous fat impingement between the fibula and the shoe rim or shoe buckle.     

Efficient radiological assessment of the internal snapping hip syndrome

The aim of this study was to evaluate the diagnostic value/significance of various imaging techniques for demonstrating the underlying causative pathology of clinically suspected internal snapping hip syndrome. We intended to define the most efficient diagnostic imaging algorithm that leads to a specific definite therapy for this rare hip disorder. The imaging studies of 54 patients (43 women, 11 men, average age 58 years) with the clinical suspicion of internal snapping hip syndrome were compared for their diagnostic value/significance for finding the underlying pathology. Radiological workup included plain radiographs of the pelvis and hip joints (n=54), ultrasound (US) of the hip joints (n=29), computed tomography (CT) of the pelvis and proximal femur (n=17), and magnetic resonance imaging (MRI) of the pelvis/hip joint (n=21). In order to establish an efficient diagnostic algorithm we compared the diagnostic value of each imaging technique alone and in combination with the other methods. The underlying causative pathology could be established in 37% of patients (n=20) by the use of conventional radiographs alone and in 46% of the patients (n=25) by US alone, and in combination in 83% of the patients (n=45). By adding CT to the radiological workup, we established final diagnosis in 88% (in combination with X-ray; n=15/17) and 94% (together with X-ray and US; n=16/17) of the patients. Whenever MR imaging was used a causative pathology was found in all patients (100%; n=21). The most efficient radiological algorithm in the assessment of patients with internal snapping hip syndrome is the combination of plain radiography and US. MR imaging can be retained for unresolved and difficult cases.     

Shoulder imaging in athletes

Shoulder pain and injuries are common in athletes. Overhead athletes, in particular, place great demands on the shoulder and supporting structures. Magnetic resonance (MR) imaging is well suited to evaluation of the osseous structures and soft tissues of the shoulder and plays an important role in evaluation of shoulder pain in athletes. Primary extrinsic impingement is well evaluated on MR imaging as are the less common posterior superior glenoid impingement and subcoracoid impingement. Rotator cuff tendinosis as well as partial- and full-thickness tears are frequently encountered in the athletic shoulder. The biceps tendon and rotator interval capsular structures are important sources of shoulder pain. Glenohumeral instability that results from a traumatic event or atraumatic multidirectional recurrent instability is assessed. The biceps labral complex is a source of considerable anatomic variability and pathology.     

Soft-tissue and osseous impingement syndromes of the ankle: role of imaging in diagnosis and management.

Soft-tissue and osseous impingement syndromes of the ankle can be an important cause of chronic pain, particularly in the professional athlete. The main impingement syndromes are anterolateral, anterior, anteromedial, and posterior impingement. These conditions arise from initial ankle injuries, which, in the subacute or chronic situation, lead to development of abnormal osseous and soft-tissue thickening within the ankle joint. The relative contributions of the osseous and soft-tissue abnormalities are variable, but whatever component is dominant there is physical impingement and painful limitation of ankle movement. Conventional radiography is usually the first imaging technique performed and allows assessment of any potential bone abnormality, particularly in anterior and posterior impingement. Computed tomography (CT) and isotope bone scanning have been largely superseded by magnetic resonance (MR) imaging, but the accuracy and role of MR imaging in assessment of possible ankle impingement have not been clearly established. MR imaging can demonstrate osseous and soft-tissue edema in anterior or posterior impingement. Studies of conventional MR imaging have produced conflicting sensitivities and specificities in assessment of anterolateral impingement. CT and MR arthrographic techniques allow the most accurate assessment of the capsular recesses, albeit with important limitations in diagnosis of clinical impingement syndromes.     

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.     

Femoroacetabular impingement

Femoroacetabular impingement is a relatively recently appreciated "idiopathic" cause of hip pain and degenerative change. Two types of impingement have been described. The first, cam impingement, is the result of an abnormal morphology of the proximal femur, typically at the femoral head-neck junction. Cam impingement is most common in young athletic males. The second, pincer impingement, is the result of an abnormal morphology or orientation of the acetabulum. Pincer impingement is most common in middle-aged women. This article reviews the imaging findings of cam and pincer type femoroacetabular impingement. Recognition of these entities will help in the selection of the appropriate treatment with the goal of decreasing the likelihood of early degenerative change of the hip.     

髋部疼痛常见病的磁共振表现

目的:探讨髋部疼痛病因的MRI影像学表现与鉴别诊断,为正确诊断髋部疼痛提供参考依据。方法:收集我院2005年8月～2009年7月期间,以髋部局部疼痛为主要临床症状的325例患者MRI资料。回顾性分析导致髋部局部疼痛的发病部位,病因及其MRI表现,探讨MRI对髋部疼痛的鉴别诊断价值。结果:引起髋部局部疼痛病因可来源于多个部位,包括骨盆、骶髂关节、腰椎等病变以及腹壁、泌尿生殖道、腹膜后间隙病变。其致病原因亦复杂多变,包括肌肉、肌腱软组织损伤,软骨损伤,关节脱位,骨折,梨状肌综合症,髋部弹响综合症,感染,关节游离体,骨性关节炎,股骨头无菌坏死,骨肿瘤,软组织肿瘤,泌尿系结石及椎间盘突出等多种疾病。结论:成人髋关节疼痛可由多种不同病因引起,可以直接与髋关节有关,也可以与髋关节周围结构有关,甚至与髋关节无关的结构如腰椎,腹膜后疾病。对于髋部疼痛,应根据临床表现选择适当影像学检查,综合考虑各种病因进行诊断。     

Imaging of hip disorders in athletes

Normal hip joint function is fundamental in running-, jumping-, and kicking-based sporting activities. Hip disorders do not account for a large portion of exercise-related injuries, but they can pose a clinical dilemma since symptoms tend to be non-specific. Conventional radiographs may demonstrate some causes of hip pain, such as stress fractures and degenerative joint disease. Magnetic resonance (MR) imaging of the hip has proven valuable in the diagnosis of radiographically occult osseous abnormalities and periarticular soft tissue disorders such as stress fractures, avulsion injuries, musculotendinous abnormalities, and bursitis. Conventional MR imaging has been less useful in the evaluation of intra-articular lesions including acetabular labral tears, intra-articular loose bodies, and cartilage lesions. The visualization of intra-articular structures and their abnormalities can be improved by the injection of diluted Gadolinium, which distends the capsule and leaks into labral tears. This article will focus on the use of conventional radiography and MR imaging in recreational and professional athletes with painful hip joints, and where possible it will compare MR imaging with other diagnostic modalities such as bone scan and CT.     

MRI of the rotator cuff and internal derangement

Disease to the rotator cuff is the most common cause of shoulder pain and dysfunction in adults. This group of muscles performs multiple functions and is often stressed during various activities. The anatomy and physiology of the rotator cuff is complex and interconnected to other muscle groups in the shoulder. One must take the anatomic status of the rotator cuff tendons into account when planning the treatment of the rotator cuff injury. Diagnostic imaging of the rotator cuff, performed by MRI, provides valuable information about the nature of the injury. In this article, we will review the various types and causes of rotator cuff injuries, normal MR anatomy, function, patho-anatomy, and the biomechanics of the rotator cuff. We will also review shoulder impingement syndromes.     

A review of femoroacetabular impingement in athletes

There are a multitude of well recognized hip and groin injuries that commonly affect athletes; however, a more recently recognized and possibly often overlooked cause of hip pain is that of femoroacetabular impingement (FAI). FAI is characterized by abutment of the femoral neck against the acetabular rim, which may occur by two mechanisms known as 'CAM' or 'pincer' impingement, although most commonly by a mixture of both. CAM impingement is characterized by abutment of the femoral neck against the acetabulum due to a morphological abnormality of the femoral head-neck junction. Pincer impingement occurs where an abnormality of the acetabulum results in impingement against an often normal femoral neck. Both CAM and pincer impingement are known to result in pathological consequences of cartilage delamination and labral lesions, leading to significant pain and disruption to athletic performance and activities of daily living in athletes. There are currently several methods of assessing the degree of impingement by use of CT and magnetic resonance imaging scans, which can be used in conjunction with magnetic resonance arthrography and arthroscopy to assess the damage caused to the underlying structures of the hip. Both open and arthroscopic surgical methods are used, with recent reports in athletes showing excellent results for lifestyle improvement and frequency of returning to sport. In cases of hip and groin pain in athletes, it is important to remember to look for typical history, and examination and imaging findings that may suggest a diagnosis of hip impingement. This article goes some way to explaining the principles, consequences and management of FAI.     

Imaging findings of femoroacetabular impingement syndrome

Femoroacetabular impingement syndrome (FAI) is a pathologic entity which can lead to chronic symptoms of pain, reduced range of motion in flexion and internal rotation, and has been shown to correlate with degenerative arthritis of the hip. History, physical examination, and supportive radiographic findings such as evidence of articular cartilage damage, acetabular labral tearing, and early-onset degenerative changes can help physicians diagnose this entity. Several pathologic changes of the femur and acetabulum are known to predispose patients to develop FAI and recognition of these findings can ultimately lead to therapeutic interventions. The two basic mechanisms of impingement—cam impingement and pincer impingement—are based on the type of anatomic anomaly contributing to the impingement process. These changes can be found on conventional radiography, MR imaging, and CT examinations. However, the radiographic findings of this entity are not widely discussed and recognized by physicians. In this paper, we will introduce these risk factors, the proposed supportive imaging criteria, and the ultimate interventions that can help alleviate patients symptoms.