Association of intramuscular cysts of the rotator cuff with tears of the rotator cuff: magnetic resonance imaging findings and clinical significance

A Comparative Assessment Between High-resolution Ultrasonography and Field Magnetic Resonance Imaging in Supraspinatus Tear Cases and Its Arthroscopic Correlation

Background

Diagnosis of a supraspinatus tear in patients presenting with shoulder pain is a difficult task and often requires the help of an MRI. However, in recent years, high-resolution ultrasonography (USG) has been utilized as a cheaper yet sensitive alternative. The aim of the study is to provide a comparative assessment of supraspinatus tears between USG and MRI in relation to arthroscopic results.

Methods

A total of 60 patients with shoulder pain for the last three months or more scheduled to undergo arthroscopic surgery for their shoulder disorder were enrolled; those having any congenital deformity of the shoulder or having any contradiction to an MRI were excluded from the assessment. All the patients underwent high-resolution ultrasonography (HRUSG) and MRI evaluation. Both the USG and MRI findings were correlated with the arthroscopic findings.

Results

On ultrasonography, 34 (56.67%) full-thickness tears and 22 (36.67%) partial-thickness tears of the supraspinatus were detected. On MRI, 36 (60.0%) were diagnosed as a full-thickness tear and 20 (33.33%) as a partial-thickness tear. After arthroscopy, 36 (60.00%) were confirmed as a full-thickness tear and 20 (33.33%) as a partial-thickness tear of the supraspinatus. For a full-thickness tear, the sensitivity and specificity of USG and MRI were 95.0% and 92.5%, and 85% and 92.5%, respectively. For a full-thickness tear, the sensitivity and specificity of the modalities were 94.4% and 100%, respectively.

Conclusion

HRUSG and MRI both had high comparable accuracy for detection of a supraspinatus tear, however, HRUSG had an edge over MRI in the detection of a partial tear.

Massive Acromioclavicular Joint Cyst with Intramuscular Extension: Case Report and Review

Acromioclavicular cysts are an uncommon manifestation secondary to a massive rotator cuff tear and/or a degenerative osteoarthritic AC joint. We present a case of an 80-year-old female with a symptomatic acromioclavicular cyst that extended intramuscularly into the trapezius. She did not complain of symptoms associated with a massive rotator cuff tear; however, the cyst has been increasing in size and she was interested in having it removed. Intraoperatively, the mass extended into the trapezius muscle and was removed en bloc after dissecting it down to the stalk. A distal clavicle excision was then performed using an oscillating saw. After the cyst was excised, it was incised revealing thick mucoid content. The patient did well postoperatively at the three-month follow-up without signs of recurrence. To our knowledge, this is the first case of AC joint cyst with intramuscular extension that was managed operatively.

Reliability and validity of the closed kinetic chain upper extremity stability test

[Purpose] The purpose of this study was to examine the reliability and validity of the Closed Kinetic Chain Upper Extremity Stability (CKCUES) test. [Subjects and Methods] A sample of 40 subjects (20 males, 20 females) with and without pain in the upper limbs was recruited. The subjects were tested twice, three days apart to assess the reliability of the CKCUES test. The CKCUES test was performed four times, and the average was calculated using the data of the last 3 tests. In order to test the validity of the CKCUES test, peak torque of internal/external shoulder rotation was measured using an isokinetic dynamometer, and maximum grip strength was measured using a hand dynamometer, and their Pearson correlation coefficients with the average values of the CKCUES test were calculated. [Results] The reliability of the CKCUES test was very high (ICC=0.97). The correlations between the CKCUES test and maximum grip strength (r=0.78–0.79), and the peak torque of internal/external shoulder rotation (r=0.87–0.94) were high indicating its validity. [Conclusion] The reliability and validity of the CKCUES test were high. The CKCUES test is expected to be used for clinical tests on upper limb stability at low price.

The deltoid, a forgotten muscle of the shoulder

The deltoid is a fascinating muscle with a significant role in shoulder function. It is comprised of three distinct portions (anterior or clavicular, middle or acromial, and posterior or spinal) and acts mainly as an abductor of the shoulder and stabilizer of the humeral head. Deltoid tears are not infrequently associated with large or massive rotator cuff tears and may further jeopardize shoulder function. A variety of other pathologies may affect the deltoid muscle including enthesitis, calcific tendinitis, myositis, infection, tumors, and chronic avulsion injury. Contracture of the deltoid following repeated intramuscular injections could present with progressive abduction deformity and winging of the scapula. The deltoid muscle and its innervating axillary nerve may be injured during shoulder surgery, which may have disastrous functional consequences. Axillary neuropathies leading to deltoid muscle dysfunction include traumatic injuries, quadrilateral space and Parsonage-Turner syndromes, and cause denervation of the deltoid muscle. Finally, abnormalities of the deltoid may originate from nearby pathologies of subdeltoid bursa, acromion, and distal clavicle.

Magnetic resonance imaging of rotator cuff disease and external impingement

Magnetic resonance (MR) imaging plays a major role in helping to identify rotator cuff disease and in demonstrating the pathology associated with external impingement. Many surgeons rely on MR imaging to assist in decision making and presurgical planning for patients with rotator cuff pain. This article reviews the etiology of external impingement and rotator cuff tears, and describes the MR imaging appearance of the normal and the pathologic rotator cuffs. It focuses on the supraspinatus tendon because this is the tendon involved in 95% of rotator cuff tears.

Current imaging of the rotator cuff

Rotator cuff pathology is a common cause of shoulder pain, and imaging plays a major role in the management of shoulder problems. General radiography may be useful as an initial screening test particularly in trauma and arthritis. Musculoskeletal ultrasound and magnetic resonance imaging are the most suitable modalities for the investigation of the rotator cuff, having high sensitivities and specificities for full-thickness tears. Musculoskeletal ultrasound and magnetic resonance imaging are less accurate in the detection of partial-thickness tears with greater observer variability. This article reviews the normal and pathologic imaging features of the rotator cuff and highlights the potential usefulness and limitations of various imaging modalities in the assessment of the tendon and the potential impact of imaging findings on clinical patient care.

Rupture of the anterior cruciate ligament in children: early reconstruction with open physes or delayed reconstruction to skeletal maturity?

The purpose of this study was to compare two different strategies of management for ACL rupture in skeletally immature patient. In group 1, patients were treated in a children hospital by ACL reconstruction with open physis. In group 2, patients were treated in an adult hospital by delayed reconstruction at skeletal maturity assessed radiologically. Fifty-six consecutive patients were included in this retrospective study. Mean time from injury to surgery in group 1 and 2 was, respectively, 13.5 and 30 months. Patients from group 2 exhibited a higher rate of medial meniscal tears (41%) compare to group 1 (16%) and higher rate of meniscectomy. Both groups had the same rate of lateral meniscal tears. A temporary tibial valgus deformity was reported which was subsequently spontaneously resolved. No definitive growth disturbance was noticed. At 27 months mean follow-up, a best subjective IKDC score was found in group 1. Objective IKDC and radiological results were similar in both groups. Early ACL reconstruction is therefore a recommended option.

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.

The anatomy of the proximal tibia in pediatric and adolescent patients: implications for ACL reconstruction and prevention of physeal arrest

Although the treatment of anterior cruciate ligament (ACL) tears in skeletally immature patients is still controversial, several studies have advocated ACL reconstruction in selected patients to prevent secondary injury. The proximal tibial physis is a structure at risk during ACL reconstruction in young patients, and physeal growth complications have been reported after surgery in this area. The relationship between the ACL and the proximal tibial physeal/apophyseal regions is poorly understood. This study examined the MRI anatomy of the ACL and the proximal tibia apophysis and epiphysis. MRIs of 59 skeletally immature knees were reviewed (Average age = 12.75 years, range 6-15) to define the anatomy of the epiphyseal and apophyseal regions. Measurements were recorded in three parasagittal planes: (1) at the lateral border of the patellar tendon, (2) the lateral edge of the ACL insertion, and (3) the medial edge of the ACL insertion. A single three-dimensional (3D) computed tomography (CT) scan was used to evaluate the position of standard drill holes used in ACL reconstruction to assess for potential degree of injury to the epiphyseal and apophyseal growth plates. In the parasagittal planes, the average height of the epiphysis was 19.6, 20.7, and 21.5 mm at the lateral border of the patellar tendon, the lateral border of the ACL, and the medial border of the ACL, respectively. At the level of the same landmarks, the apophysis extended below the physis at an average of 20.2, 16.8, and 7.0 mm, respectively. Expressed as a percentage of epiphysis height this was an average of 104, 82, and 33%, respectively. Examination of 3D CT images revealed that variations in drill hole placement had effects on the volume of injury to the proximal tibial physis and apophysis. Drill holes that started more medial, distal, and with a steeper angle of inclination reduced the amount of physis and apophysis violated when compared with holes placed more lateral, proximal, and with a shallow angle of inclination. The proximal tibial physis and apophysis is vulnerable to injury by drill hole placement during ACL reconstruction in skeletally immature patients. This paper defines the anatomic relationship of the apophyseal and epiphyseal regions of the physis in the proximal tibia. The volume of injury to the physis can be reduced by avoiding tunnel placement that is too lateral or too proximal on the tibia. A better understanding of these relationships may guide the placement of tibial drill holes, which have a lower risk of producing significant physeal damage.

MR imaging of the rotator cuff

MR imaging is the optimal method for evaluating suspected rotator cuff pathology. Current techniques of fast spin-echo imaging without and with fat suppression allow accurate identification and characterization of tendinous and myotendinous abnormalities of the rotator cuff. Impingement disorders, tendon degeneration, instability,and trauma comprise the multifactorial nature of rotator cuff disease. This article addresses the role of MR imaging in evaluating the rotator cuff and the importance of MR imaging in identifying other lesions that may mimic rotator cuff pathology. A rationale for protocol design, including MR arthrography and the use of specialized positioning, such as abduction and external rotation (ABER), are discussed.

Age and gender effects on lower extremity kinematics of youth soccer players in a stop-jump task

BACKGROUND

Gender differences in lower extremity motion patterns were previously identified as a possible risk factor for non-contact anterior cruciate ligament injuries in sports.

HYPOTHESIS

Gender differences in lower extremity kinematics in the stop-jump task are functions of age for youth soccer players between 11 and 16 years of age.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Three-dimensional videographic data were collected for 30 male and 30 female adolescent soccer players between 11 and 16 years of age performing a stop-jump task. The age effects on hip and knee joint angular motions were compared between genders using multiple regression analyses with dummy variables.

RESULTS

Gender and age have significant interaction effects on standing height (P = .00), body mass (P = .00), knee flexion angle at initial foot contact with the ground (P = .00), maximum knee flexion angle (P = .00), knee valgus-varus angle (P = .00), knee valgus-varus motion (P = .00), and hip flexion angle at initial foot contact with the ground (P = .00).

CONCLUSION

Youth female recreational soccer players have decreased knee and hip flexion angles at initial ground contact and decreased knee and hip flexion motions during the landing of the stop-jump task compared to those of their male counterparts. These gender differences in knee and hip flexion motion patterns of youth recreational soccer players occur after 12 years of age and increase with age before 16 years.

CLINICAL RELEVANCE

The results of this study provide significant information for research on the prevention of noncontact anterior cruciate ligament injuries.

Intramuscular Rotator Cuff Cysts: Association with Tendon Tears on MRI and Arthroscopy

OBJECTIVE

This study was designed to explore the relationship between intramuscular cysts and rotator cuff tendon tears.

CONCLUSION

Intramuscular cysts are strongly associated with rotator cuff tendon tears. Identification of such a cyst should prompt a search for a rotator cuff tear. Findings on MR arthrography and surgery suggest that a delaminating component of the rotator cuff tear may lead to the development of these cysts and may explain the occasional discrepancy between location of tears and location of cysts.

Anterior cruciate ligament injury in pediatric and adolescent soccer players: an analysis of insurance data

Injury claims from an insurance company specializing in soccer coverage were reviewed for a 5-year period. A total of 8215 injury claims (3340 females, 4875 males) were divided into three categories: (1) all injury, (2) knee injury, and (3) ACL injury. Knee injuries accounted for 22% of all injuries (30% female, 16% male). ACL injury claims represented 31% of total knee injury claims (37% female, 24% males). The youngest ACL injury was age 5. The ratio of knee injury/all injury increased with age. Compared with males, females demonstrated a higher ratio of knee injury/all injury and a higher ratio of ACL injury/all injury. This study demonstrates that ACL injury occurs in skeletally immature soccer players and that females appear to have an increased risk of ACL injury and knee injury compared with males, even in the skeletally immature. Future research related to ACL injury in females will need to consider skeletally immature patients.

Intramuscular ganglion arising from the acromioclavicular joint

We report a case of a 80-year-old White woman presenting with a localized painless swelling in the upper parascapular region of the right shoulder. Ultrasound (US) showed a ganglion arising from the acromioclavicular joint (ACJ) and extending inside the trapezius muscle, together with a massive tear of the rotator cuff (RC). Magnetic resonance imaging (MRI) confirmed the US findings. Ganglia arising from the ACJ are rare and usually associated with massive RC tears. Their intramuscular extension, to the best of our knowledge, has never been reported in the radiological literature and can mimic a tumor.

Delayed anterior cruciate ligament reconstruction in adolescents with open physes

BACKGROUND

Treatment of anterior cruciate ligament rupture in adolescents with open physes is controversial.

HYPOTHESIS

Delaying reconstruction until the physes bridge will affect the rate of additional knee injuries.

STUDY DESIGN

Case control.

METHODS

The physes group was 13 adolescents with open physes whose anterior cruciate ligament reconstructions were delayed until their physes bridged. Specific types of activity were absolutely restricted during the delay. The physes groups' rates of additional injuries, identified arthroscopically at reconstruction, were compared to rates among 116 skeletally mature adolescents. The comparison adolescents were stratified into four groups by interval from injury to reconstruction (<1 week, 1 to 6 weeks, 6 to 26 weeks, >26 weeks).

RESULTS

The additional injury rates in the physes and four comparison groups were 46%, 50%, 47%, 43%, and 69%, respectively. Severity of additional injury, mechanism of injury, and rate of additional surgical procedures were similar among the groups.

CONCLUSIONS

There was no evidence that intentionally delayed anterior cruciate ligament reconstruction increased the rate of additional knee injuries. Delayed reconstruction is a valid treatment option for adolescents with open physes at injury. Absolute activity restriction is key to decreasing the risk of additional knee injuries.

Magnetic resonance imaging of the shoulder: rotator cuff

Magnetic resonance imaging has proven to be useful in the assessment of rotator cuff injuries. Improvements in magnetic resonance techniques, including fast spin-echo imaging and fat saturation, have facilitated demonstration of tendinous abnormalities of the rotator cuff. Rotator cuff disease is multifactorial. Primary impingement within the coracoacromial arch, degeneration of the rotator cuff tendons, trauma, and glenohumeral instability may be contributing factors. Shoulder pain in athletes can be related to acute myotendinous and muscle injuries, which can be easily detected using magnetic resonance imaging.

Horizontal component of partial-thickness tears of rotator cuff: imaging characteristics and comparison of ABER view with oblique coronal view at MR arthrography initial results

PURPOSE

To determine the characteristics of horizontal components of partial-thickness tears of the rotator cuff at magnetic resonance (MR) arthrography and to determine whether use of the abduction and external rotation (ABER) position improved detection of a horizontal component in partial-thickness tears.

MATERIALS AND METHODS

MR studies in 16 patients (mean age, 32 years) who had partial-thickness tear with a horizontal component were retrospectively evaluated. All 16 patients had undergone arthroscopic surgery. The depth and extent of the horizontal component were measured on MR images, and the presence or absence of articular surface tear was recorded. The characteristics of the horizontal component on ABER views were compared with those on oblique coronal views.

RESULTS

A horizontal component (24 lesions; one tendon involved in eight patients and two tendons involved in eight patients) was observed in 100% of the lesions on ABER views and in 21% of the lesions (n = 5) on oblique coronal images. The mean length of the horizontal components, measured on ABER views, was 1.9 cm (range, 0.6-4.5 cm). Thirteen (54%) of the 24 lesions were classified as grade I (<3 mm) in depth, four (17%) were classified as grade II (3-6 mm), and seven (29%) were classified as grade III (>6 mm). Articular separation sites with a flap lesion were visualized in 15 (62%) of 24 lesions on ABER views.

CONCLUSION

MR arthrography of the shoulder with patients in the ABER position may provide additional information in cases of partial-thickness tears of the rotator cuff with a horizontal component.

Intramuscular fluid collections and their association with longitudinal rotator cuff tears

This study draws attention to the association between intramuscular fluid collections occurring at the myo-tendinous junction of the rotator cuff secondary to longitudinal tears of their tendons.