Pectoralis major muscle and tendon tears: diagnosis and grading using magnetic resonance imaging

 Objective. To assess the accuracy and utility of magnetic resonance (MR) imaging in the detection and grading of pectoralis major muscle and tendon tears. Design and patients. A retrospective review was carried out of 10 patients referred for MR imaging for suspected pectoralis muscle injury and possible operative therapy. The pectoralis muscle and tendon were imaged using thin (3–4 mm) axial sections with a variety of sequences combined for anatomical delineation (T1-weighted SE or PD SE) and fluid detection (T2-weighted SE, T2-weighted FSE with fat suppression, or STIR). Surgical correlation was available in six patients. Clinical follow-up was available in four patients treated by nonoperative therapy. Results. MR imaging identified five complete tears, four partial tears and one normal tendon. One complete and one partial tear were at the myotendinous junction. The remaining seven injuries were at the enthesis. Surgical correlation consisted of five complete tears and one partial tear. One complete and one partial tear were at the myotendinous junction with the remaining four complete tears at the enthesis. The MR interpretation and surgical findings were in agreement in all six cases. All four patients treated with nonoperative therapy demonstrated improvement at a clinical follow-up examination, with restoration of function and strength consistent with a healed prior partial injury. Conclusion. MR imaging is accurate and useful in detecting and grading tears involving the pectoralis major muscle and tendon, facilitating the identification of patients with complete tears who are candidates for operative therapy. Received: 7 June 1999 Revision requested: 22 June 1999 Revision received: 16 February 2000 Accepted: 21 February 2000     

MR imaging assessment of the pectoralis major myotendinous unit: an MR imaging-anatomic correlative study with surgical correlation

OBJECTIVE: MR imaging is the optimal imaging technique to study the normal and abnormal conditions of the pectoralis major muscle and tendon unit. The purpose of this study was to use MR imaging to provide an anatomic survey of the normal pectoralis major tendon and its insertion and to compare these findings with surgically proven cases of rupture. CONCLUSION: MR imaging shows the normal pectoralis major myotendinous unit has low signal intensity on both T1- and T2-weighted images. Reliable anatomic landmarks for visualization and examination of injuries to the muscle and myotendinous unit include the quadrilateral space, or the origin of the lateral head of the triceps, as the superior boundary and the deltoid tuberosity as the inferior boundary of the intact tendon of insertion. Failure to visualize a normal insertion within these boundaries should prompt a dedicated search by the radiologist for rupture and retraction of the tendon medially.     

Magnetic resonance imaging of muscle injury

To further evaluate the role of magnetic resonance (MR) imaging in diagnosing and managing muscle injuries, eight patients with muscle pain or palpable masses were imaged. MR findings were correlated with clinical follow-up data. Increased signal was noted on T2-weighted images in torn and overused muscles. One extensively scarred muscle required surgical biopsy to exclude a fibrous tumor. Three partial muscle tears were treated conservatively. One complete musculotendinous junction tear required tendon transfer. MR studies noninvasively identified and staged various muscle injuries, thereby influencing management.     

Knee dislocations: a magnetic resonance imaging study correlated with clinical and operative findings

OBJECTIVES: Our objectives were to determine retrospectively the prevalence, patients' demographics, mechanism of injury, combination of torn ligaments, associated intra-articular and extra-articular injuries, fractures, bone bruises, femoral-tibial alignment and neurovascular complications of knee dislocations as evaluated by magnetic resonance (MR) imaging. MATERIALS AND METHODS: From 17,698 consecutive knee examinations by magnetic resonance imaging (MRI) over a 6-year period, 20 patients with knee dislocations were identified. The medical records of these patients were subsequently reviewed for relevant clinical history, management and operative findings. RESULTS: The prevalence of knee dislocations was 0.11% [95% confidence interval (95% CI) 0.06-0.16)]. There were 16 male patients and four female patients, with ages ranging from 15 years to 76 years (mean 31 years). Fifteen patients had low-velocity injuries (75%), of which 11 were amateur sports related and four were from falls. Four patients (20%) had suffered high-velocity trauma (motor vehicle accidents). One patient had no history available. Anatomic alignment was present at imaging in 16 patients (80%). Eighteen patients had three-ligament tears, two had four-ligament tears. The four-ligament tears occurred with low-velocity injuries. The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were torn in every patient; the lateral collateral ligament (LCL) was torn in 50%, and the medial collateral ligament (MCL) in 60%. Intra-articular injuries included meniscal tears (five in four patients), fractures (eight in seven patients), bone bruises (15 patients), and patellar retinaculum tears (eight partial, two complete). The most common extra-articular injury was a complete biceps femoris tendon tear (five, 25%). There were two popliteal tendon tears and one iliotibial band tear. One patient had received a vascular injury following a motor vehicle accident (MVA) and had been treated prior to undergoing MRI. Bone bruises (unrelated to fractures), four-ligament tears, biceps femoris tears, and popliteus tendon tears were encountered only in the low-velocity knee dislocations. Twelve were treated surgically, five conservatively, and three had been lost to follow-up. The biceps femoris tendon was repaired in every patient who was treated surgically. CONCLUSIONS: Knee dislocations occurred more commonly in low-velocity injuries than in high-velocity injuries, predominantly affecting amateur athletes. Biceps femoris tendon tears were the most common extra-articular injury requiring surgery. Neurovascular injury (5%) was uncommon. At imaging, femoral-tibial alignment was anatomic in the majority of patients.     

MR imaging of the knee. Part I. Traumatic disorders

One hundred thirty patients with a diversity of knee joint injuries were evaluated with a high-resolution magnetic resonance (MR) imaging technique. The authors report the accuracy of this technique in the evaluation of 105 patients with suspected meniscal tears, 26 patients with suspected cruciate ligament tears, and eight patients with suspected patellar tendon injuries. Of those menisci rated as definitely or probably torn on MR imaging, 80% were found to be torn at subsequent arthroscopy. The predictive value of negative MR imaging results was 100%. MR imaging was 92% accurate in predicting the clinical outcome in patients with suspected meniscal tears who did not undergo surgery. MR permitted complete disruption of the patellar tendon to be differentiated from partial tears, ligamentous inflammation, and localized effusion of the infrapatellar bursa. Injuries to the anterior and posterior cruciate ligaments were identified on MR images, and the status of synthetic grafts of the anterior cruciate ligament was ascertained.     

Diagnosis of popliteus injuries with MR imaging

Objective. Popliteal muscle and tendon injuries are thought to be unusual. This report describes the magnetic resonance (MR) appearances of popliteus muscle and tendon injuries. Design and patients. The study included 24 patients where the diagnoses of popliteal injuries were prospectively made based on MR appearances. The study group was taken from 2412 consecutive knee MRIs. The injuries were characterized as to involving the muscular or tendinous portions of the popliteus apparatus. Results. In 95.8% (23/24) of patients, the tears of the popliteus involved the muscular portion. The injuries were either partial and interstitial or complete. Three patients had tears of both the muscular and tendinous portions or the tendon alone. The anterior and posterior cruciate ligaments were torn in 16.7% (4/24) and 29.2% (7/24) of patients, respectively. There were medial and lateral meniscal tears in 45.8% (11/24) and 25% (6/24) of patients, respectively. There were injuries of the medial and lateral collateral ligaments in 8.3% (2/24) and 4.2% (1/24) of patients, respectively. Bone bruises and/or fractures were seen in 33.3% (8/24) patients. In 8.3% (2/24) of patients, the popliteus injury was an isolated finding. Conclusion. Popliteus muscle and tendon injuries are not uncommon. They usually occur in conjunction with other significant injuries of the knee and can be characterized with MR imaging.Presented at RSNA, Chicago, Illinois, December 1992     

Deltoid muscle and tendon tears in patients with chronic rotator cuff tears

Purpose To describe the magnetic resonance imaging (MRI) appearances of tears of the deltoid muscle and tendon in patients with rotator cuff tears and without a prior history of shoulder surgery. Materials and methods Deltoid tears diagnosed on MR examinations were prospectively recorded between February 2003 through June 2004. The images of these patients were then retrospectively reviewed to determine the location of the deltoid tear, the presence of rotator cuff tears, tendon retraction, muscle atrophy, degree of humeral head subluxation, bony erosive changes involving the undersurface of the acromion, and the presence of edema or fluid-like signal intensity in the deltoid muscle and overlying subcutaneous tissues. Results There were 24 (0.3%) patients with deltoid tears; nine men and 15 women. The age range was 54 to 87 (average 73) years. The right side was involved in 20 cases, and the left in four cases. Fifteen patients had full thickness and nine had partial thickness tears of the deltoid. Shoulder pain was the most common presenting symptom. The physical examination revealed a defect in the region of the deltoid in two patients. Nineteen patients had tears in the muscle belly near the musculotendinous junction, and five had avulsion of the tendon from the acromial origin. Full thickness rotator cuff tears were present in all of the patients, and 22 patients had associated muscle atrophy. Subcutaneous edema and fluid-like signal was present in 15 patients. Conclusion Tears of the deltoid muscle or tendon is an unusual finding, but they can be seen in patients with chronic massive rotator cuff tears. Partial thickness tears tend to involve the undersurface of the deltoid muscle and tendon. Associated findings such as intramuscular cyst or ganglion in the deltoid muscle belly and subcutaneous edema or fluid-like signal overlying the deltoid in a patient with a rotator cuff tear should raise the suspicion of a deltoid tear.     

Magnetic resonance imaging in acute and chronic rotator cuff tears

Magnetic resonance imaging has been assessed in patients with acute rotator cuff tears and normal radiographs (9 cases) and those with chronic tears and changes of cuff arthropathy (9 cases). All images were obtained using a low field strength system (FONAR 0.3 T). Particular attention was placed on the appearances of the tendon and the cuff muscles themselves. Six complete acute tears were clearly identified, but MRI failed to demonstrate two partial tears. Muscle bulk was preserved in all patients in this group. In contrast, all patients with cuff arthropathy had complete tears of the supraspinatus tendon with marked tendon retraction and associated muscle atrophy: these changes precluded primary surgical repair. MRI should be used to assess muscle atrophy preoperatively in those patients with acute tears. When plain radiographs demonstrate cuff arthropathy, the MRI appearances are predictable and primary repair is unlikely to be successful. Further imaging is therefore not indicated.     

Everything pectoralis major: from repair to transfer

ABSTRACT

Background: Pectoralis major ruptures are increasing in incidence primarily due to an increase in awareness, activity level among young males between 20 and 40 years of age, and use of anabolic steroids. Although the majority of pectoralis major ruptures are acute injuries, many chronic ruptures are unrecognized and it is imperative to understand the proper evaluation of these injuries, as well as the appropriate treatment for acute and chronic ruptures.

Purpose: Pectoralis major ruptures can lead to deformity and physical disability if left untreated. This review paper discusses both acute and chronic ruptures as well as indications for nonoperative treatment and operative treatment to give the reader the best understanding of this diagnosis and proper management.

Methods: A systematic review of the literature was performed using a search of electronic databases. Search terms such as pectoralis major rupture, pectoralis major repair, pectoralis major tendon transfer, and pectoralis major nonoperative treatment were used. Case reports, systematic reviews, prospective and retrospective studies were included to provide a comprehensive review. The only exclusion criteria consisted of studies not published in English. This review article includes the anatomy and biomechanics of the pectoralis major muscle, proper evaluation of the patient, operative and nonoperative treatment of acute and chronic pectoralis major ruptures, and outcomes of the recommended treatment.

Conclusion: Nonoperative treatment is indicated for patients with medical comorbidities, older age, incomplete tears, or irreparable damage. Patients treated non-operatively have been shown to lose strength, but regain full range of motion. Patients with surgery before 6 weeks reported better outcomes than patients with surgery between 6 and 8 weeks. The chronicity of the rupture (>8 weeks) increases the likelihood of reconstruction, involving the use of autografts or allografts. Patients treated with delayed repair had significantly better strength, satisfaction, and outcomes than patients with nonoperative treatment. The pectoralis tendon can also be transferred in patients with rotators cuff tears, atrophy, or significant functional limitation. Tendon transfers have been shown to have unpredictable outcomes, but overall satisfactory results.     

Posteromedial tibial plateau injury including avulsion fracture of the semimembranous tendon insertion site: ancillary sign of anterior cruciate ligament tear at MR imaging.

PURPOSE: To evaluate posteromedial tibial plateau injuries of or about the semimembranous tendon insertion site and their association with anterior cruciate ligament (ACL) tears on magnetic resonance (MR) images. MATERIALS AND METHODS: A retrospective study of MR images and conventional radiographs was performed in 10 patients with posteromedial tibial plateau injuries, including avulsion fractures of the semimembranous tendon insertion site. Associated abnormalities were analyzed, including ACL tears, medial meniscal tears, and other lateral femorotibial compartment injuries. Findings from the clinical history and physical examination were correlated with radiographic and MR imaging findings. Nine patients had arthroscopically or surgically documented ACL tears. RESULTS: All 10 patients had ACL tears at MR imaging. Five patients had posteromedial tibial plateau fractures: Four had avulsion fractures of the tendon insertion site, and one had a fracture lateral to the site. Five patients had posteromedial tibial plateau bruises: Two had bruises at the tendon insertion site. Five patients had tears of the posterior horn of the medial meniscus. Two patients had posterior meniscocapsular separations. Three patients showed evidence of the O'Donoghue triad. Six patients had bruises of the lateral tibial plateau and of the lateral femoral condyle. CONCLUSION: There appears to be an association between posteromedial tibial plateau injuries and ACL tears. Posteromedial tibial plateau injuries may be predictive of ACL status.     

Pectoralis major tendon avulsion from rappelling

To our knowledge, we are reporting the first case of a pectoralis major tendon avulsion from rappelling. The mechanism of injury in this case differs biomechanically from the commonly associated activity of bench pressing. The patient's initial presentation, course of corrective treatment, and postoperative rehabilitation is discussed in detail. A review of the historical and current literature on pectoralis major tendon injuries is included. The results of current biomechanical studies are discussed in relation to the complex anatomy of the pectoralis major muscle. This report is relevant to individuals involved in rappelling, high-demand athletes, and the surgeons who treat them. Nonoperative management of pectoralis major tendon tears is contrasted with operative repair. The current literature supports operative treatment in high-demand athletes, laborers, and military personnel to allow them to regain full strength and endurance.     

MR imaging of the metacarpophalangeal joints of the fingers: evaluation of 38 patients with chronic joint disability

Objective To report the MR imaging findings of painful injured metacarpophalangeal (MCP) joints of the fingers.Design and patients MR imaging of 39 injured MCP joints in 38 patients was performed after a mean delay of 8.8 months. The MR images were obtained with the fingers in extended and flexed positions using T2-weighted and T1-weighted sequences before and after intravenous injection of a gadolinium compound. Ten patients were treated surgically. Mean clinical follow-up was 1.8 years.Results Tears of the collateral ligaments were the most common lesion (30/39), most being radial in location. Contrast-enhanced axial T1-weighted images with the MCP joint in a flexed position showed these lesions optimally. Ten tears were partial and 20 were complete. In 13 patients, MR images showed 17 associated lesions including injuries of the extensor hood (10/17), interosseous tendon (3/17), palmar plate (3/17), and an osteochondral lesion (1/17). Sagittal MR images were essential to highlight palmar plate tears.Conclusion Partial or complete tears of the collateral ligaments are prevalent MR imaging findings in patients with chronic disability resulting from injuries to the MCP joints. Although conservative treatment generally is sufficient for isolated injuries of the collateral ligaments, surgical repair is often required in cases of more extensive injuries. MR imaging may clearly delineate associated lesions of and about the MCP joints.     

Delayed repair of a ruptured pectoralis major muscle. A case report

Repair of a pectoralis major muscle rupture at the tendinous insertion into the humerus was successfully performed 13 years after the initial injury. Repair was possible only because the ruptured sternal portion of the muscle was scarred to the intact clavicular portion and therefore had not retracted. The attachment of the avulsed sternal head to the intact clavicular head enabled successful restoration of strength and function, as well as normal contour and appearance of the pectoralis major muscle complex.     

MR assessment of the repaired rotator cuff: prevalence, size, location, and clinical relevance of tendon rerupture

The objectives of this study were to use magnetic resonance (MR) imaging to evaluate the prevalence, size, location, and clinical relevance of tendon rerupture following complete repair of full-thickness rotator cuff tear (RCT). A total of 78 surgically proven full-thickness rotator cuff tears in 74 patients were retrospectively included in the study. Clinical assessment was performed using the University of California at Los Angeles score. Postoperative MR imaging was evaluated to determine prevalence, size, and location of tendon rerupture. At a mean 48.4 months’ follow-up, 62 shoulders (79.5%) had favorable outcomes and 45 shoulders (57.6%) showed rerupture on MR imaging studies. Reruptures were significantly more prevalent among patients with intermediate-to-bad outcomes (81.3%), with surgically demonstrated two-tendon tears (78.9%) or three-tendon tears (100%), and with preoperative fatty degeneration of the supraspinatus muscle greater than 1 (91.6%). Reruptures were also significantly larger in those subgroups. Complete repair of RCT of all sizes may have favorable outcomes in a significant proportion of patients in spite of a high prevalence of reruptures. Preoperative tear size and degree of muscle fatty degeneration influence the prevalence and rerupture size. After repair of supraspinatus tears, reruptures tend to invade the posterior aspect of the tendon.     

Achilles tendon injuries: the role of MR imaging

Eight magnetic resonance (MR) examinations were performed in seven patients with Achilles tendon injuries and correlated with physical examination and surgical and clinical follow-up. The MR examinations depicted the Achilles tendon in excellent detail and Achilles tendon abnormalities with greater accuracy than physical examination. Of five tendons shown to be at least partially torn on MR, palpable tendinous defects were found in only one, and plantarflexion weakness was found in four. The MR and surgical findings precisely correlated in one case. Magnetic resonance proved valuable in the evaluation of clinically equivocal Achilles tendon tears and may ultimately play a greater role as a research tool in the determination of optimal forms of therapy for specific Achilles tendon injuries.     

Can isotropic fast gradient echo imaging be substituted for conventional T1 weighted sequences in shoulder MR arthrography at 3 Tesla?

PURPOSE: To assess the practical utility of isotropic shoulder imaging in patients undergoing MR arthrography. Isotropic shoulder imaging can be performed in less than three minutes with use of fast gradients. MATERIALS AND METHODS: Two experienced musculoskeletal radiologists retrospectively interpreted MR images of the shoulder in 100 consecutive patients undergoing MR arthrography of the shoulder. All patients underwent MRI of the shoulder in oblique coronal, oblique sagittal, and axial planes on a 3.0-Tesla MRI system. All patients had conventional fast spin-echo T1-weighted imaging. All patients also had thin section (0.4 mm) isotropic spoiled gradient echo images performed. A total of 67 of the 100 patients underwent subsequent arthroscopy and results were compared with MR interpretations. RESULTS: There were 41 full-thickness supraspinatus tendon tears, nine partial-thickness supraspinatus tendon tears (seven articular surface and two bursal surface), 21 superior labral, 18 anterior labral, and seven posterior labral tears demonstrated by consensus retrospective reading of the 100 shoulder MR exams. There was no difference in interpretation of the isotropic images as compared to the conventionally acquired images in the oblique coronal, oblique sagittal, and axial planes. Some patients had more than one finding on each exam. A total of 67 patients went on to arthroscopy. There were 41 full-thickness supraspinatus tendon tears, nine partial-thickness supraspinatus tendon tears, 21 superior labral, 18 anterior labral, and seven posterior labral tears demonstrated on arthroscopy. All full- and partial-thickness supraspinatus tendon tears seen at arthroscopy were seen on consensus MR reading. A total of 19 out of the 21 patients with superior labral anterior posterior (SLAP) tears at arthroscopy were seen on consensus MR reading. A total of 16 of the 18 anterior labral tears and six of the seven posterior labral tears seen at arthroscopy were seen on consensus MR reading. Some of the 67 patients had more than one finding on arthroscopy. CONCLUSION: Isotropic imaging of the shoulder is practical in clinical imaging when performed with use of fast gradients on a 3-Tesla system. Isotropic imaging provides the same clinical information as conventional imaging and can be acquired in less than three minutes.     

Accuracy of MR findings in characterizing peroneal tendons disorders in comparison with surgery

Background Previous studies have shown that magnetic resonance imaging (MRI) has a high sensitivity for peroneal tendon pathology but more studies with surgery as a reference standard are needed. Purpose To evaluate the accuracy of MRI compared to surgery for characterizing chronic peroneal tendon pathology. Material and Methods Ninety-seven patients (57 men, 40 women; mean age, 39 years; range, 15-64 years) with chronic lateral ankle instability underwent MRI followed by surgery, with a mean MR to surgery interval of 30 days. Sagittal, coronal, and axial T1-weighted spin-echo and fat-suppressed T2-weighted fast spin-echo images were obtained for all patients. Two blinded observers evaluated the MR images without clinical information, and the results were compared to surgical findings. The following peroneal injuries were observed: tendon split, interstitial tear, swelling of the tendon, fluid collection, superior peroneal retinaculum injury, and tendon dislocation. Results Swelling of the peroneus longus tendon was the most common finding on MR imaging, followed by fluid collection and a split of the peroneus brevis tendon. Surgical findings showed that nine cases (9%) of interstitial tears were in the peroneus brevis and two cases (2%) were in the peroneus longus, with eight cases (8%) of splits in the peroneus brevis tendon. The sensitivity and specificity for detecting interstitial tears in the peroneus brevis were 44% and 99%, respectively. The sensitivity and specificity for detecting swelling in the peroneus brevis were 50% and 99%, respectively. The sensitivity and specificity for detecting interstitial tears for peroneus longus injuries were 50% and 96%, respectively. The sensitivity and specificity for detecting swelling in these injuries were and 100% and 96%, respectively. Conclusion MRI findings of chronic peroneal tendon pathology are diagnostically specific but not sensitive. MRI showed high sensitivity for diagnosing tendon swelling in the peroneus longus, but not in the peroneus brevis. MRI is sensitive but not specific for detecting negative findings.     

Gamekeeper thumb: Diagnosis of ulnar collateral ligament injury using magnetic resonance imaging,magnetic resonance arthrography and stress radiography

Ulnar collateral ligament (UCL) tears may be nondisplaced or displaced relative to the adductor pollicis aponeurosis. Nondisplaced tears typically heal with immobilization whereas displaced tears require surgery. Nineteen patients with UCL injuries were evaluated using MR imaging (MRI), MR arthrography, and stress radiography (SR) to determine the efficacy of these techniques in differentiating nondisplaced from displaced UCL tears. Nineteen patients with UCL injuries were evaluated. MRI was utilized in 5 patients, and MR arthrography in 14, with 12 of these 14 undergoing SR. They were followed until resolution of symptoms; those without relief, and those with suspected displaced UCL tears were surgically explored. Surgery and imaging was correlated. Eight patients underwent surgical repair. SR was abnormal in six patients treated surgically, but was negative in four of six conservatively treated patients with MR findings of nondisplaced tears. All patients with MR or MR arthrographic findings interpreted as being normal or as having a nondisplaced tear improved after conservative treatment. Based on surgical findings and clinical follow-up, MR arthrography accurately diagnosed 13 of 14 UCL injuries, with one false-positive interpretation. SR is often falsely negative. MR imaging with or without intra-articular contrast injection proved to be accurate in a small series of patients with UCL injuries.     

Injuries to the distal gastrocnemius muscle: MR findings

PURPOSE: The purpose of this work was to demonstrate the MR findings of injuries to the distal gastrocnemius muscle. METHOD: Twenty patients with clinically confirmed injuries to the distal gastrocnemius muscle underwent MRI. The injuries were evaluated with regard to abnormal morphology or signal abnormality, site, and degree of tearing. RESULTS: Twenty-three injuries to the distal gastrocnemius occurred in 20 patients, with involvement of the myotendinous junction in 22 of 23 (96%) injuries. An interstitial tear of the proximal Achilles tendon was present in one instance. Myotendinous strains were the most common injuries (10/23; 43%); partial tears (7/23; 30%) and complete tears (5/23; 22%) of the myotendinous junction or proximal Achilles tendon were less frequent. When an injury to the gastrocnemius myotendinous junction was present, involvement of the medial head (19/22; 86%) was more frequent than involvement of the lateral head (3/22; 14%). CONCLUSION: MRI allows accurate imaging of distal gastrocnemius muscle injuries. When occurring, distal gastrocnemius muscle injuries most frequently involve the myotendinous junction of the medial gastrocnemius head and occasionally the lateral gastrocnemius head or the proximal Achilles tendon.