Posterior dislocation in a voluntary subluxator: a case report

Posterior Shoulder Instability in the Patients with Bilateral Congenital Absence of Long Head of Biceps Tendon: A Case Report

Rare cases of a congenital absence of the long head of the biceps tendon (LHBT) have been reported, and its incidence is unknown. In a literature review of the congenital absence of the LHBT, only 1 case was associated with posterior shoulder instability and severe posterior glenoid dysplasia. This paper reports the first case of a patient with a bilateral congenital absence of the LHBT with posterior shoulder instability without glenoid dysplasia or posterior glenoid tilt. The patient experienced a traffic accident while holding the gear stick with his right hand. After the accident, a posteroinferior labral tear with paralabral cysts was detected on the magnetic resonance images. The congenital absence of the LHBT was assumed to have affected the posterior instability that possibly increased the susceptibility to a subsequent traumatic posterior inferior labral tear. This case was identified as a posterior inferior tear caused by a traumatic ‘gear stick injury’.

Functional outcome and quality of life after rehabilitation for voluntary posterior shoulder dislocation: a prospective blinded cohort study

BACKGROUND

Voluntary posterior instability of the shoulder is a rare condition in which the patient is able to cause a subluxation by voluntary muscle activation. A shoulder rehabilitation program aimed to correct abnormal muscle patterns and restore correct scapular motion may provide good results and improve the quality of life of these patients.

METHODS

Fifteen subjects (six males, nine females; mean age 19 years) underwent physical examination and clinical tests [Disability of the Arm, Shoulder and Hand (DASH) score, Shoulder Pain and Disability Index (SPADI), and modified Rowe score] and compiled the patient global assessment (PGA). Articular or rotator cuff lesions were excluded by X-rays and MRI. The rehabilitation program included three phases: (1) assessment and correction of abnormal muscle patterns, (2) restoration of correct scapular motion, and (3) strengthening of scapular and posterior glenohumeral muscles. Follow-up was at 3, 6, 12, and 24 months.

RESULTS

DASH and SPADI scores improved significantly at 3 (p < 0.01), 6 (p < 0.009), 12 (p < 0.001), and 24 months (p < 0.001). The Rowe score was fair at 3 months and good at 6, 12, and 24 months. Active flexion, abduction, and external rotation increased at all follow-up points (p < 0.01), whereas internal rotation remained unchanged (p > 0.05). PGA values were high. Compliance was good without serious adverse events reported during the treatment. A correlation was found between age and DASH changes (Spearman's ρ -0.56; p = 0.0455).

CONCLUSIONS

Our findings stress the value of a rehabilitation program that teaches subjects with voluntary instability how to correct abnormal muscle patterns to restore scapular motion, and the importance of adopting home rehabilitation exercises as a part of the normal lifestyle.

Absence of the long head of the biceps tendon associated with glenoid dysplasia and posterior labral tear

Anatomic variations in the insertion of the long head of the biceps tendon and superior labral complex have been described (Erickson et al. [1992] AJR Am. J. Roentgenol. 158:1091-1096; Kreitner et al. [1998] AJR Am. J. Roentgenol. 170:599-605; Mariani et al. [1997] Arthroscopy 13:499-501; Vangsness Jr. et al. [1994] J. Bone Joint Surg. Br. 76:951-954). To the authors' knowledge, there have been only five reported cases of congenital absence of the long head of the biceps tendon. Three of these cases were associated with anterior shoulder instability, one with a superior labral anterior posterior lesion and one simply with shoulder pain. This is the first reported case of congenital absence of the biceps tendon associated with glenoid dysplasia and a posterior labral tear.