Capsule Of The Glenohumeral Joint Research Articles

Patient Satisfaction after Thermal Shrinkage of the Glenohumeral-Joint Capsule

Objective:To determine whether patients were satisfied after thermal shrinkage on the capsule of the glenohumeral joint (GHJ).Design and Setting:The affected shoulder was assessed preoperatively and 2 months postoperatively. The assessment evaluated pain on activities of daily living (ADLs), physical activity level, satisfaction with shoulder function, and a modified UCLA pain scale.Subjects:Eight athletes, 4 men and 4 women, with a mean age of 21 years, participated. Each had sustained a traumatic injury to the GHJ resulting in multidirectional instability.Measurements:Subjects were evaluated preoperatively and 2 months postoperatively for GHJ laxity and labral deformity. Goniometric measurements of flexion/extension, abduction/adduction, and internal/external rotation of the GHJ were completed.Results:Six of the 8 subjects had reduced pain. Active extension increased significantly in 7. ADLs were all improved. All 8 subjects were satisfied with the thermal-shrinkage procedure.Conclusions:Thermal shrinkage of the capsule of the GHJ results in patient satisfaction and reduced pain.

ガングリオンによる紋やく性肩甲上神経障害

We operated on three patients with entrapment of the suprascapular nerve by a ganglion, but there was a recurrence in a first case after one year. We represent surgical techniques to allow neurolysis and complete removal of the ganglion in the spinoglenoid notch, reporting our surgical experience with the other two cases.«A case report» Case 3. A 42-year-old worker gave a 7-month history of pain in his right (dominant) shoulder. He had difficulty in elevating his arm. On examination there was marked wasting of infraspinatus. EMG confirmed denervation of only infraspinatus. MRI showed a ganglion straddling the base of the spine of the scapula. At surgery, the spine of the scapula was cut to allow adequate exposure. Coloring matter was injected into the ganglion to find out its origin. It arose from the anterior superior capsule of the glenohumeral joint and its neck was ligated. We performed complete removal of the ganglion and neurolysis. SLAP lesion was found using arthroscopy of the shoulder. After the operation, pain was relieved. Fourteen months later the power of external rotation had improved and ultrasound examination confirmed no recurrence.

The pattern of the collagen fiber bundles of the capsule of the glenohumeral joint

The macroscopic anatomy and the architecture of the collagen fiber bundles were studied in the joint capsules of 43 cadaver shoulders. All the specimens were transilluminoted by polarized light after preparation by Spalteholz' technique. Areas of high-fiber density and complex structure were examined histologically. The macroscopically recognizable ligaments are composed of collagen fiber bundles in several layers of differing thickness and orientation. A simple pattern of radial and circular fibers is found only in the relatively thin posterior capsule. A complex pattern of cross-linking was visible in the superior capsule, and a system of fiber bundles spirally crossing each other was present in the anterior/inferior capsule. The examination under polarized light revealed a continuous transition between the ligamentous reinforcements at the anterior inferior capsule, which radiated obliquely from the glenoid rim and varied greatly in form and orientation. The complicated structure of the joint capsule would suggest that the capsular cylinder has to be regarded as a functional entity and that the current biomechanical concepts must be modified if we want to understand its stabilizing effect. The structural features of the superior capsule present new insight about the pathogenesis of rotator cuff tearing, which can develop as a result of shearing stress between the capsular and tendinous layers.

Supporting Layers of the Glenohumeral Joint

Based on anatomic and surgical dissections, the anatomy of the shoulder region is described in terms of four layers that overlie and support the glenohumeral joint. Each layer envelops the glenohumeral joint on its anterior, lateral, and posterior aspects, and between each layer there is a plane for safe and easy dissection. Layer 1 is composed of the deltoid and pectoralis major muscle bellies with their overlying fascia and enveloping epimysium. Anteriorly, Layer 2 consists of the clavipectoral fascia, the conjoined tendon of the short head of the biceps and coracobrachialis, and the coracoacromial ligament. Posteriorly, Layer 2 is the dense posterior scapular fascia that overlies the infraspinatus and teres minor muscle bellies. It is continuous with the clavipectoral fascia around the lateral aspect of the proximal humerus. Deep to Layer 2, the subdeltoid bursa yields a dissection plane that encompasses the anterior, lateral, superior, and variably the posterior aspects of the glenohumeral joint. Layer 3 consists of the deep layer of the subdeltoid bursa and the underlying musculotendinous units of the rotator cuff, including subscapularis, supraspinatus, infraspinatus, and teres minor. Layer 4 is the capsule of the glenohumeral joint. This includes the glenohumeral ligaments and coracohumeral ligament. These four layers were present and consistent in each shoulder dissected. Significant variations were present only within the deepest layer (shoulder joint capsule). This system can serve as a learning tool and will provide a more organized approach to facilitate surgical dissection in the region.

Capsular properties of the shoulder.

The purpose of this study was to determine the structural properties of the capsule of the glenohumeral joint. Twelve fresh frozen cadaveric shoulders were studied. Capsular strips were prepared from four different sites (anterior, posterior, superior, and inferior) of the capsule. One end of the capsular sections was left attached to the humerus, and the other excised was fixed in a clamp of an Instron universal testing machine. Maximum load, strength (maximum stress), and modulus of elasticity of these four capsular portions were measured. The most common mode of failure was tear at the midsubstance (68%), followed by tear at the clamp-capsule junction (23%), and detachment from the humerus (9%). The posterior capsule (1.0 +/- 0.4 mm) was thinner than the anterior (1.8 +/- 0.3 mm), superior (1.6 +/- 0.4 mm), and inferior capsule (1.5 +/- 0.3 mm). Among the four portions of the capsule, the posterior capsule showed the greatest strength (216.6 +/- 58.2 kg/cm2) and modulus of elasticity (683.1 +/- 228.8 kg/cm2), whereas the superior capsule showed the least strength (82.4 +/- 33.5 kg/cm2). There were no significant differences in maximum load. The greater strength of the posterior capsule may be one explanation for the low incidence of posterior shoulder dislocation.