Search

Hip pain is a common and complex clinical entity. The causes of hip injuries in athletes are many and diverse, requiring efficient, accurate diagnosis for proper management. Imaging is an important step in the clinical evaluation of hip pain, and familiarity with multiple imaging modalities as well as characteristic imaging findings is a helpful tool for sports medicine clinicians. This article discusses imaging recommendations and gives imaging examples of common causes of intra-articular and extra-articular hip pain including femoroacetabular impingement, labral tears, cartilage defects, ligamentum teres injuries, snapping hip syndrome, femoral stress injuries, thigh splints, athletic pubalgia, avulsion injuries, and hip dislocation.

Hip pain is a common and complex clinical entity. The causes of hip injuries in athletes are many and diverse, requiring efficient, accurate diagnosis for proper management. Imaging is an important step in the clinical evaluation of hip pain, and familiarity with multiple imaging modalities as well as characteristic imaging findings is a helpful tool for sports medicine clinicians. This article discusses imaging recommendations and gives imaging examples of common causes of intra-articular and extra-articular hip pain including femoroacetabular impingement, labral tears, cartilage defects, ligamentum teres injuries, snapping hip syndrome, femoral stress injuries, thigh splints, athletic pubalgia, avulsion injuries, and hip dislocation.

Background Shoulder pseudodislocation, or “drooping shoulder,” presents with acute pain and deformity of the joint, with radiographs demonstrating inferior subluxation of the humeral head relative to the glenoid fossa. The diagnosis must be made promptly and distinguished from true glenohumeral dislocation, both to avoid unnecessary attempts at closed reduction and to facilitate investigation of the underlying cause, which may include septic arthritis, hemarthrosis, or other emergent etiologies. Point-of-care ultrasound (POCUS) may be useful in the evaluation of emergency department (ED) patients with suspected pseudodislocation. Case Report A 50-year old female presented to the ED with an acutely painful and deformed shoulder but atypical history and physical examination. Initial radiography appeared to show a glenohumeral dislocation, but POCUS, done to guide intra-articular lidocaine injection, led to recognition of pseudodislocation and subsequent diagnosis of calcific tendinitis/bursitis, a condition not previously associated with inferior humeral subluxation. Why Should an Emergency Physician Be Aware of This? Shoulder pseudodislocation must be considered in the evaluation of patients with suspected glenohumeral dislocation, but atypical features on history, physical examination, or initial plain radiography. POCUS may facilitate prompt diagnosis and identification of the underlying etiology.

Objectives To retrospectively characterize the ultrasound appearance of palmar fibromatosis in patients with a surgical or clinical diagnosis of palmar fibromatosis. Methods A search of ultrasound reports from 2005 to 2015 and a subsequent search of medical records were performed to identify patients with a surgical or clinical diagnosis of palmar fibromatosis. The ultrasound images were retrospectively reviewed to record the lesion location, size, echogenicity, compressibility, hyperemia, and calcification. Results A total of 36 patients were identified (average age, 60 years; 61% male), yielding a total of 55 palmar fibromatosis lesions, of which 2%, 7%, 29%, 36%, 20%, and 5% were located at the first, second, third, fourth, and fifth digits and between the fourth and fifth digits, respectively. The lesions were located directly superficial to the flexor tendons in 93% with their epicenters at the distal metacarpal in 89%. Average lesion dimensions were 13.1 mm in length, 6.8 mm in width, and 2.5 mm in depth. On ultrasound images, the lesions were characteristically hypoechoic (98%) and noncompressible (95%). Atypical features included calcification (2%), compressibility (5%), hyperemia on color Doppler images (6%), epicenters at the metacarpophalangeal joint (7%) or proximal phalanx (4%), and location superficial but lateral to the flexor tendons (7%). Conclusions Palmar fibromatosis most commonly appears hypoechoic and is located directly superficial to the flexor tendons with an epicenter at the distal metacarpal, most commonly the fourth digit. However, the epicenter location may be at the distal metacarpal and proximal phalanx of other digits, adjacent to the flexor tendons, with possible hyperemia and calcification.

Describe the imaging appearance of well-differentiated liposarcoma with myxoid stroma (WDLMS) and correlate with histopathology. A keyword search of the institution medical records was performed from 1 January 2000 to 30 June 2017. The histopathology slides of cases identified in this fashion were then reviewed by a pathologist. Additional cases were prospectively collected from extramural referrals and tumor boards. Diagnostic imaging studies of pathologically proven cases of WDLMS were then reviewed in consensus and correlated with pathology. Ten cases of pathologically proven WDLMS were identified (7 men, 3 women, ages 26–81). Tumor location included the retroperitoneum (n = 5), thigh (n = 4), and the shin (n = 1). Nine patients had macroscopic fat on imaging. The nonlipomatous components had a variable appearance, including septal, nodular, and lacelike patterns. Two cases included two distinct areas that were predominantly myxoid or lipomatous (“bi-morphic”). One tumor had no macroscopic fat on imaging. On CT, the nonlipomatous nodular components were hypodense/had hypodense areas. On MRI, the nodular components had intermediate/bright T2W signal. Interval nonlipomatous nodular growth was identified in 3 cases. WDLMS may present on imaging as a mass with variable morphology and amounts of nonlipomatous components. Histopathological diagnosis of WDLMS is challenging and imaging correlation may be helpful, as this tumor may have ≥50% fatty volume, may have a myxoid nodular component or bi-morphic appearance, or may be located in the retroperitoneum, features that are unusual for myxoid liposarcoma. WDLMS with a nodular component cannot be distinguished from dedifferentiated liposarcoma based on imaging alone.

Stephen R. Covey's landmark work in the field of effectiveness and professional development delineated first 7, then ultimately eight, habits of highly effective people with applicability to all professions.1 This article describes the eight habits in specific relation to the radiologist, and proposes a ninth habit to help one bring a positive and centered approach during the journey to effectiveness and beyond.

Of the many treatment options for tendinopathy, percutaneous tenotomy has been used throughout the body with success. With this procedure, a needle is repeatedly passed into the abnormal tendon with the goal of converting a chronic degenerative process to an acute inflammatory condition that will progress to tendon healing. Ultrasound guidance for this procedure is essential to ensure that the abnormal region of the tendon is accurately targeted. The treatment has few contraindications, and negligible complications have been described. This article reviews the rationale behind tenotomy for the treatment of tendinopathy and the ultrasound-guided technique. The current literature comparing the results of tenotomy to other percutaneous tendon treatments is also reviewed, although many of the other tendon injection treatments incorporate tenotomy as part of the procedure.

Pain and other disorders of the knee are a common presenting complaint in the ambulatory setting. Although the cornerstones of imaging evaluation of the knee are radiographs and magnetic resonance (MR) imaging, ultrasonography (US) is less expensive than MR imaging, easily available, and of comparable accuracy in the evaluation of certain pathologic conditions of the knee. The benefits of US include portability, low cost, high spatial resolution, dynamic imaging, and ability to guide percutaneous interventions when indicated. US also allows direct patient contact, facilitating immediate clinical correlation and the ability to compare with the contralateral knee. US evaluation of the knee can be targeted to a specific region on the basis of the complaint or be a comprehensive review. For comprehensive evaluation, the knee is divided into anterior, medial, lateral, and posterior compartments for structured evaluation of the tendons, ligaments, joint space, osseous structures, as well as peripheral nerves and vasculature. US is particularly well suited for evaluating injuries of the quadriceps and patellar tendons, injuries of the medial and lateral collateral ligaments, joint effusions, and fluid collections around the knee. There is additional utility in evaluation of the distal hamstrings tendons, the iliotibial tract, the superficial patellar cortex, the common peroneal nerve, the popliteal vessels, and juxta-articular cystic collections including Baker cyst. In-depth appreciation of relevant sonographic anatomy, common pathologic conditions, knowledge of important pitfalls, and mastery of US technique will allow one to effectively use this powerful bedside tool for the evaluation of a wide variety of knee disorders. ©RSNA, 2016.

To retrospectively characterize the ultrasound appearance of palmar fibromatosis in patients with a surgical or clinical diagnosis of palmar fibromatosis.A search of ultrasound reports from 2005 to 2015 and a subsequent search of medical records were performed to identify patients with a surgical or clinical diagnosis of palmar fibromatosis. The ultrasound images were retrospectively reviewed to record the lesion location, size, echogenicity, compressibility, hyperemia, and calcification.A total of 36 patients were identified (average age, 60 years; 61% male), yielding a total of 55 palmar fibromatosis lesions, of which 2%, 7%, 29%, 36%, 20%, and 5% were located at the first, second, third, fourth, and fifth digits and between the fourth and fifth digits, respectively. The lesions were located directly superficial to the flexor tendons in 93% with their epicenters at the distal metacarpal in 89%. Average lesion dimensions were 13.1 mm in length, 6.8 mm in width, and 2.5 mm in depth. On ultrasound images, the lesions were characteristically hypoechoic (98%) and noncompressible (95%). Atypical features included calcification (2%), compressibility (5%), hyperemia on color Doppler images (6%), epicenters at the metacarpophalangeal joint (7%) or proximal phalanx (4%), and location superficial but lateral to the flexor tendons (7%).Palmar fibromatosis most commonly appears hypoechoic and is located directly superficial to the flexor tendons with an epicenter at the distal metacarpal, most commonly the fourth digit. However, the epicenter location may be at the distal metacarpal and proximal phalanx of other digits, adjacent to the flexor tendons, with possible hyperemia and calcification.

OBJECTIVES Percutaneous ultrasound-guided needle fenestration has been used to treat tendinopathy of the elbow, knee, and ankle with promising results. The purpose of this study was to evaluate the clinical outcome of ultrasound-guided fenestration of tendons about the hip and pelvis. METHODS After Institutional Review Board approval, a retrospective search of imaging reports from January 1, 2005, to June 30, 2011, was completed to identify patients treated with ultrasound-guided tendon fenestration about the hip or pelvis. Subsequent clinic notes were retrospectively reviewed to determine whether the patient showed marked improvement, some improvement, no change, or worsening symptoms. RESULTS The study group consisted of 22 tendons in 21 patients with an average age of 55.8 years (range, 26.7-77.0 years). The treated tendons included 11 gluteus medius (9 tendinosis and 2 partial tears), 2 gluteus minimus (both tendinosis), 8 hamstring (6 tendinosis and 2 partial tears), and 1 tensor fascia latae (tendinosis). The average interval to clinical follow-up was 70 days (range, 7-813 days). There was marked improvement in 45.5% (10 of 22), some improvement in 36.4% (8 of 22), no change in symptoms in 9.1% (2 of 22), and worsening symptoms in 9.1% (2 of 22). There were no patient variables (age, chronicity of symptoms, sex, tendon, tendinosis versus tear, prior physical therapy, and prior corticosteroid injection) that were significantly different between patients who improved and those who did not. There were no cases of a subsequent tendon tear or infection. CONCLUSIONS Clinical follow-up after ultrasound-guided fenestration of the gluteus medius, gluteus minimus, proximal hamstring, and tensor fascia latae tendons showed that 82% of patients had improvement in their symptoms.

OBJECTIVE. Patients who undergo knee MRI for presumed musculoskeletal disease can have unexpected vascular findings or pathology in the imaged field. Some vascular processes are limb threatening and affect treatment planning and patient outcome. CONCLUSION. Unexpected vascular findings on knee MRI can range from incidental to symptomatic and can include such processes as variant anatomy, aneurysm, traumatic injury, and neoplasm. The assessment for vascular pathology should be a key component of every radiologist's search pattern when evaluating knee MRI.

MR imaging appearances of different types of reconstructive muscle flaps following reconstructive surgery of the lower extremity with associated post-surgical changes due to altered anatomy, radiation, and potential complications, can be challenging. A multidisciplinary therapeutic approach to tumors allows for limb salvage therapy in a majority of the patients. Decision-making for specific types of soft tissue reconstruction is based on the body region affected, as well as the size and complexity of the defect. Hematomas and infections are early complications that can jeopardize flap viability. The local recurrence of a tumor within six months after a complete resection with confirmed tumor-free margins and adjuvant radiation therapy is rare. Identification of a new lesion similar to the initial tumor favors a finding of tumor recurrence.

There has been a renewed interest in the recent literature with regard to the normal anatomy of the distal biceps tendon. Cadaveric studies have demonstrated that a large percentage of individuals have two independent muscle bellies, the short and the long head, with two distinct separate tendons attaching at the radial tuberosity. To avoid diagnostic errors that may have an impact on patient management in case of tendon injury, it is important to keep this anatomical variant in mind. Ultrasonography has been shown to be a useful imaging modality in the evaluation of disorders of the distal biceps brachii muscle and tendon. In this article, we review the relevant anatomy of the distal biceps brachii, the ultrasound technique with alternative approaches for optimum visualization of the distal tendon, and the most common pathologies in this region.

We report a new lateral approach for ultrasound visualization of the distal biceps tendon. A cadaver specimen was dissected to study distal biceps anatomy relevant to this approach. Sonograms obtained in volunteers and patients are provided to illustrate this alternative method.

We have noted apparent far lateral meniscal attachment of the meniscofemoral ligament (MFL) with an anterior cruciate ligament (ACL) tear. This study evaluates MFL attachment and association with posterior horn lateral meniscus (PHLM) tear. Nine months of knee arthroscopy reports were reviewed to classify the PHLM and ACL as torn or normal. After excluding those with prior knee surgery, MR images were reviewed by two radiologists to determine the number of images lateral to PCL, which showed the ligaments of Humphrey and Wrisberg visible as structures separate from the PHLM. Any patient with abnormal PHLM surface signal not continuous with the MFL was excluded. MRI findings were compared with arthroscopy using Student’s t test and Fisher’s exact test. Of the 54 participants, 5 had PHLM tears and 49 were normal. Twenty-one had ACL tears; all those with an PHLM tear had an ACL tear. The ligament of Humphrey inserted on average 0.9 consecutive images lateral to the PCL without an PHLM tear and 4.7 with an PHLM tear; the ligament of Wrisberg inserted on average 3.0 consecutive images without an PHLM tear and 4.5 with an PHLM tear (slice thickness/gap = 3 mm/0.5 mm). There was a significant association between PHLM tear and number of images (p = 0.0028), and between ACL tear and this type of PHLM tear (p = 0.0064). Apparent far lateral meniscal extension of a meniscofemoral ligament (greater than or equal to four images lateral to the PCL) should be considered as a possible PHLM tear, especially in the setting of an ACL tear.

OBJECTIVE. We have found in our practice that the normal extensor retinaculum of the wrist may appear hypoechoic on sonography and, because it is closely applied to the extensor tendons, may simulate tenosynovitis. This study prospectively evaluates the extensor retinaculum in 50 healthy adult volunteers, characterizing its sonographic appearance.CONCLUSION. The extensor retinaculum has a characteristic appearance on sonography. A hypoechoic appearance from anisotropy should not be confused with tenosynovitis.

The anatomy of the nerves of the foot and ankle is complex, and familiarity with the normal anatomy and course of these nerves as well as common anatomic variants is essential for correct identification at imaging. Ultrasonography (US) and magnetic resonance (MR) imaging allow visualization of these nerves and may facilitate diagnosis of various compression syndromes, such as "jogger's heel," Baxter neuropathy, and Morton neuroma. It may be difficult to distinguish the nerves from adjacent vasculature at MR imaging, and US can help in differentiation. The authors review the normal anatomy and common variants of the nerves of the foot and ankle, with use of dissected specimens and correlative US and MR imaging findings. In addition, the authors illustrate proper probe positioning, which is essential for visualizing the nerves at US. The authors' discussion focuses on the superficial and deep peroneal, sural, saphenous, tibial, medial and lateral plantar, medial and inferior calcaneal, common digital, and medial proper plantar digital nerves.

Six patients were retrospectively identified as having undergone lateral ligament reconstruction surgery. The surgical procedures were categorized into four groups: direct lateral ligament repair, peroneus brevis tendon rerouting, peroneus brevis tendon loop, and peroneus brevis tendon split and rerouting. At radiography and magnetic resonance (MR) imaging, the presence of one or more suture anchors in the region of the anterior talofibular ligament indicates direct ligament repair, whereas a fibular tunnel indicates peroneus brevis tendon rerouting or loop. Both ultrasonography (US) and MR imaging demonstrate rerouted tendons as part of lateral ankle reconstruction; however, MR imaging can also depict the rerouted tendon within an osseous tunnel if present, especially if T1-weighted sequences are used. Artifact from suture material may obscure the tendon at MR imaging but not at US. With both modalities, the integrity of the rerouted peroneus brevis tendon is best evaluated by following the tendon proximally from its distal attachment site, which typically remains unchanged. The rerouted tendon or portion of the tendon can then be traced proximally to its reattachment site. Familiarity with the surgical procedures most commonly used for lateral ankle ligament reconstruction, and with the imaging features of these procedures, is essential for avoiding diagnostic pitfalls and ensuring accurate assessment of the ligament reconstruction.

The high resolution and dynamic capability of ultrasound make it an excellent tool for assessment of superficial structures. The ligaments, tendons, and nerves about the elbow can be fully evaluated with ultrasound. The medial collateral ligament consists of an anterior and posterior band that can easily be identified. The lateral ligament complex consists of the radial collateral ligament, ulnar insertion of the annular ligament, and lateral ulnar collateral ligament, easily identified with specialized probe positioning. The lateral ulnar collateral ligament can best be seen in the cobra position. On ultrasound medial elbow tendons can be followed nearly up to their common insertion. The pronator teres, flexor carpi radialis, palmaris longus, and flexor digitorum superficialis can be identified. The laterally located brachioradialis and extensor carpi radialis longus insert on the supracondylar ridge. The other lateral tendons can be followed up to their common insertion on the lateral epicondyle. The extensor digitorum, extensor carpi radialis brevis, extensor digiti minimi, and extensor carpi ulnaris can be differentiated. The distal biceps tendon is commonly bifid. For a complete assessment of the distal biceps tendon specialized views are necessary. These include an anterior axial approach, medial and lateral approach, and cobra position. In the cubital tunnel the ulnar nerve is covered by the ligament of Osborne. Slightly more distally the ulnar nerve courses between the two heads of the flexor carpi ulnaris. An accessory muscle, the anconeus epitrochlearis can cover the ulnar nerve at the cubital tunnel, and is easily identified on ultrasound. The radial nerve divides in a superficial sensory branch and a deep motor branch. The motor branch, the posterior interosseous nerve, courses under the arcade of Frohse where it enters the supinator muscle. At the level of the dorsal wrist the posterior interosseous nerve is located at the deep aspect of the extensor tendons. The median nerve may be compressed at various sites, including the lacertus fibrosis, between the pronator teres heads, and the sublimis bridge. These compression sites can be identified with ultrasound. ispartof: European Journal of Radiology vol:84 issue:4 pages:671-681 ispartof: location:Ireland status: published

OBJECTIVE. Ultrasound of the thigh presents unique challenges because of the size and length of multiple structures, including tendons, muscles, nerves, and vessels. Those performing ultrasound can use a focal approach, a comprehensive approach, or a compartmental and flexible approach. CONCLUSION. This article illustrates and summarizes our approach to ultrasound of the thigh, including unique anatomy, artifacts, and common abnormalities, with an emphasis on the advantages of performing a compartment-based and flexible ultrasound examination.

Anatomic variations in the anterior aspect of the shoulder, such as an accessory head of the biceps brachii muscle, are not uncommon. The magnetic resonance imaging and arthroscopic appearance of the accessory head of the biceps brachii has been recently described. This series demonstrates the sonographic appearance of the accessory head of the biceps brachii in the bicipital groove. It is an asymptomatic, flat, echogenic structure with average measurements of 7.7 × 1.2 mm in cross section. Knowledge of this anatomic variant can avoid the misdiagnosis of a longitudinal split tear and improve the accuracy of sonography.

OBJECTIVE. The purpose of this article is to review a number of diagnostic pitfalls related to ultrasound evaluation of the hand and wrist. Such pitfalls relate to evaluation of ten-dons (extensor retinaculum, multiple tendon fascicles, tendon subluxation), inflammatory arthritis (incomplete evaluation, misinterpretation of erosions, failure to evaluate for enthesitis), carpal tunnel syndrome (inaccurate measurements, postoperative assessment), ulnar collateral ligament of the thumb (misinterpretation of the adductor aponeurosis and displaced tear), wrist ganglion cysts (incomplete evaluation and misdiagnosis), and muscle variants. CONCLUSION. Although ultrasound has been shown to be an effective imaging method for assessment of many pathologic conditions of the wrist, knowledge of potential pitfalls is essential to avoid misdiagnosis and achieve high diagnostic accuracy.

To retrospectively characterize the ultrasound appearance of displaced ulnar collateral ligament (UCL) tears that are proven at surgery, and then determine the accuracy of the resulting ultrasound criteria in differentiating displaced from non-displaced UCL tears.After institutional review board approval, 26 patients were identified from the radiology information system over a 10-year period that had ultrasound evaluation of the thumb and surgically proven UCL tear. Retrospective review of the displaced full-thickness tears was carried out to characterize displaced tears and to establish ultrasound criteria for such tears. A repeat retrospective review 4 months later of all UCL tears applied the criteria to determine accuracy of ultrasound in the diagnosis of displaced full-thickness UCL tear.The 26 subjects consisted of 17 displaced full-thickness UCL tears, seven non-displaced full-thickness tears, and two partial-thickness tears at surgery. Retrospective ultrasound review of displaced full-thickness tears identified two criteria present in all cases: non-visualization of the UCL ligament and presence of a heterogeneous mass-like area proximal to the first metacarpophalangeal joint. Applying these criteria at the second retrospective review resulted in 100 % sensitivity, specificity, positive predictive value, negative predictive value, and accuracy.The ultrasound findings of absent UCL fibers and presence of a heterogeneous mass-like abnormality proximal to the first metacarpophalangeal joint achieved 100 % accuracy in differentiating displaced from non-displaced full-thickness UCL tear of the thumb. Displaced full-thickness UCL tears most commonly were located proximal to the adductor aponeurosis.

The purpose of this research was to retrospectively characterize paralabral cysts of the hip as seen at MR arthrography.After Institutional Review Board approval, 704 patients who had MR arthrography were identified over a 3-year period and 40 patients were identified as having a cyst or fluid collection at the hip by MR report. MR images from these 40 patients were retrospectively reviewed by three radiologists where 18 were found to have a paralabral cyst, which were characterized as follows: location, configuration, contrast filling, size of the cyst, extent, direction, and whether associated osseous changes were present. In addition, the acetabular labrum was assessed for tears and, if present, the location and pattern were characterized.Paralabral cysts were located anterosuperiorly in 56%, anteriorly in 22%, posterosuperiorly in 17%, and anteroinferiorly in 6% of cases. The vast majority (94%) were multilocular and filled with intra-articular contrast medium. The average dimensions were 8 × 7 × 11 mm. The paralabral cyst demonstrated extracapsular extension in 72% of cases, with 39% located between the ilium and gluteus minimus, and 22% between the ilium and iliopsoas. Remodeling of the ilium adjacent to the cyst was observed in 50% of these cases. A labral tear was at the base of the labrum adjacent to the cyst in 78% of cases, while the tear was isolated to the body of the labrum in 22%. Tears were most commonly anterosuperior (55%) or anterior (28%) in location.Our results show that paralabral cysts of the hip are most commonly located anterosuperiorly, are multilocular, fill with intra-articular contrast medium, have average dimensions up to 11 mm, and often extend extracapsularly between muscle and bone where they may remodel the adjacent ilium.

Objective. The purpose of this series was to retrospectively characterize the sonographic appearance of posttraumatic Morel-Lavallee lesions. Methods. After Institutional Review Board approval was obtained, a search of the radiology information system database with correlation to medical records identified 21 posttraumatic fluid collections of the hip and thigh in 15 patients. Sonographic images were retrospectively reviewed by 1 author to characterize the echogenicity, homogeneity, shape, margins, location, compressibility, and vascularity of the fluid collection. Results were correlated with the age of the fluid collection and aspiration results where possible. Results. All fluid collections (21/21) were located between the deep fat and fascia, with a shape that was fusiform in 12 (60%) of 20, flat in 5 (25%), and lobular in 3 (15%) (shape not determined in 1 case). Regarding echogenicity, 15 (71%) of the 21 collections were hypoechoic, and 6 (29%) were anechoic; 13 (62%) were heterogeneous, and 8 (38%) were homogeneous. The lobular fluid collections were all less than 2 weeks of age, and the flat fluid collections were all greater than 6 months of age. All homogeneous fluid collections were greater than 8 months of age. There was no relationship between the age of a fluid collection and its echogenicity. Conclusions. Morel-Lavallee lesions had a variable appearance, being more homogeneous and flat or fusiform in shape with a well-defined margin as the lesions aged. All Morel-Lavallee lesions were hypoechoic or anechoic, compressible, and located between the deep fat and overlying fascia. Key words: hip; sonography; thigh; trauma.

To characterize the ultrasonographic (US) appearance of the rotator cuff cable in asymptomatic shoulders and in cadaveric specimens, with histologic comparison for the latter.The cadaveric portion of this study was approved by the institution's Anatomical Donations Department. Institutional review board approval and informed consent were obtained from asymptomatic volunteers and clinical patients for the HIPAA-compliant portion of the study. Four fresh cadaveric shoulder specimens (two male subjects, 40 and 50 years old) were dissected, assessed for the presence of the rotator cable, and imaged with 12-MHz US. Histologic slides (hematoxylin-eosin stain) from three resected rotator cuff tendons were inspected for fibers in the expected location and orientation of the rotator cuff cable. The shoulders in 17 asymptomatic volunteers (seven men, two women; age range, 27-66 years; mean, 41 years) and contralateral asymptomatic shoulders in 10 patients (six men, four women; age range, 24-78 years; mean, 49 years) were scanned and evaluated for the presence and appearance of the rotator cable.The rotator cable was identified at gross dissection. Histologic examination and US of the cadaveric shoulders demonstrated an articular-sided fibrillar structure perpendicular to the rotator cuff tendon (average thickness and width, 1.2 mm and 4.5 mm, respectively). US of asymptomatic shoulders depicted a similar fibrillar structure in three (11%) shoulders up to 1.1-1.5 cm medial to the greater tuberosity (average thickness and width, 1.2 mm and 4.5 mm respectively).The rotator cable can be depicted with US.

To retrospectively evaluate the imaging features of os peroneum fractures and associated peroneus longus tendon injuries at radiography and ultrasonography (US) and to retrospectively compare these imaging features with those of multipartite os peroneum.Institutional review board approval was obtained and informed consent was waived for this HIPAA-compliant study. Retrospective review of findings in nine patients (five men, four women; age range, 35-59 years) with os peroneum fracture at radiography and lateral foot pain after injury who had undergone US of the foot was performed. Three patients underwent magnetic resonance (MR) imaging, and two underwent surgery. Os peroneum fragment separation and displacement relative to the calcaneocuboid joint were measured on radiographs. Os peroneum fracture and peroneus longus tendon injuries were characterized with US and MR imaging. Review of 43 foot radiographs obtained in 36 control subjects (eight men, 28 women; age range, 18-84 years) who were found to have an os peroneum at radiography but were asymptomatic in that area was completed to measure os peroneum distance from the calcaneocuboid joint and bipartite os peroneum fragment distraction.Os peroneum fragment separation of 6 mm or more or displacement of the proximal fragment by 10 mm or more on a lateral radiograph or 20 mm or more on an oblique radiograph was associated with full-thickness peroneus longus tendon tear in seven of seven patients (100%). Os peroneum fragment separation of 2 mm or less or proximal displacement of 8 mm or less was associated with normal tendons, partial-thickness tears, or tendinosis. In the control subjects, os peroneum location ranged from 7 mm proximal to 8 mm distal to the calcaneocuboid joint on lateral radiographs and from 9 mm proximal to 8 mm distal to the joint on oblique radiographs. Bipartite os peroneum fragment separation was 2 mm or less.Os peroneum fragment separation of 6 mm or more suggests os peroneum fracture and associated full-thickness peroneus longus tendon tear. Separation of 2 mm or less may be seen with nondisplaced os peroneum fractures and bipartite os peroneum.

The purpose of this research was to describe the sonographic findings of pectoralis major injuries with clinical, surgical, and magnetic resonance imaging (MRI) correlation.Images from sonographic examinations of the pectoralis major muscle of 6 patients were retrospectively evaluated and characterized. The sonographic findings were compared with clinical, surgical, and MRI findings.The 6 patients were male (mean age, 30 years) with injuries sustained during weight lifting, football, and shotgun firing. Two of the 6 patients had MRI correlation; 1 had surgical correlation; 2 had both surgical and MRI correlation; and 1 had clinical follow-up. The sternal head was injured in 5 patients; 4 involved the musculotendinous junction, and 1 involved the distal tendon. The sonographic findings of muscle fiber retraction and surrounding hemorrhage allowed identification of the affected muscle. Direct impact injury causing hematoma involved the clavicular head in 1 patient. In total, 5 cases were partial-thickness pectoralis major tears, whereas complete distal tendon disruption was found in 1.Sonographic imaging longitudinal to the pectoralis muscle fibers showed fiber disruption, retraction, and possible hypoechoic or anechoic hematoma, most commonly involving the musculotendinous junction of the sternal head. Distal tendon assessment is important to evaluate for a full-thickness pectoralis major tear.

Complex knee injuries are common, often resulting from multiple forces: varus, valgus, hyperextension, hyperflexion, internal rotation, external rotation, anterior or posterior translation, and axial load. Certain combinations of forces are known to cause specific injury patterns. After a review of the literature, the authors developed a mechanism-based classification system based on patterns of bone marrow edema and ligament injury for complex knee injuries depicted at magnetic resonance imaging. The classification system takes into account knee position and forces and recognition of patterns of bone injury and complementary soft-tissue injury. Ten mechanism-based injury patterns were recognized: (a) pure hyperextension, (b) hyperextension with varus, (c) hyperextension with valgus, (d) pure valgus, (e) pure varus, (f) flexion with valgus and external rotation, (g) flexion with varus and internal rotation, (h) flexion with posterior tibial translation, (i) patellar dislocation (flexion, valgus, and internal rotation of femur on fixed tibia), and (j) direct trauma. Recognition of these patterns may help assess the full extent of knee injury, particularly at the posterolateral and posteromedial corners of the knee.

The anatomy of the nerves of the foot and ankle is complex, and familiarity with the normal anatomy and course of these nerves as well as common anatomic variants is essential for correct identification at imaging. Ultrasonography (US) and magnetic resonance (MR) imaging allow visualization of these nerves and may facilitate diagnosis of various compression syndromes, such as "jogger's heel," Baxter neuropathy, and Morton neuroma. It may be difficult to distinguish the nerves from adjacent vasculature at MR imaging, and US can help in differentiation. The authors review the normal anatomy and common variants of the nerves of the foot and ankle, with use of dissected specimens and correlative US and MR imaging findings. In addition, the authors illustrate proper probe positioning, which is essential for visualizing the nerves at US. The authors' discussion focuses on the superficial and deep peroneal, sural, saphenous, tibial, medial and lateral plantar, medial and inferior calcaneal, common digital, and medial proper plantar digital nerves.