[Posterior shoulder joint instability. Classification, pathomechanism,diagnosis, conservative and surgical management]

[A new reduction technique for posterior locked shoulder dislocation. Case report and technique description]

The case of a 61-year-old male with posterior dislocation of the right shoulder joint is presented and a new technique for closed reduction of posterior locked shoulder dislocation is described. The technique involves four steps: in step 1 a constant traction is applied on the injured arm, in step 2 the arm is internally rotated and in steps 3 and 4 the second arm of the physician is used as a lever arm to lateralize and ventralize the shoulder. Lateralization and ventralization of the humeral head are essential to engage the humeral head and to pass it around the glenoid during reduction. Steps 3 and 4 are performed simultaneously. In the presented case the patient suffered a traumatic shoulder dislocation with a rim fracture of the glenoid. After reduction the shoulder was stable and conservative treatment was performed. A 2 year follow-up examination revealed a pain-free and stable shoulder with free range of motion and an Oxford instability score of 48 points. The described reduction technique for posterior locked shoulder dislocation is a simple and gentle technique, which can be performed easily by one person.Presentation of a reduction technique for locked posterior shoulder dislocation. Constant traction and internal rotation is performed for engaging the locked humeral head. After disengaging the humeral head the reduction is performed by using the arm of the physician as a lever arm.

[Joint reconstruction with autologous bone cylinder and locked intramedullary nail: proximal humeral shaft fracture with ipsilateral reverse Hill-Sachs lesion]

The case of a 51-year-old patient is presented, with a humeral shaft fracture in combination with an ipsilateral reverse Hill-Sachs lesion, presumably after posterior shoulder dislocation as a result of an electrical accident followed by a fall from a ladder. After corresponding diagnostics, osteosynthesis of the shaft fracture was performed with a locked antegrade intramedullary nail. Simultaneously the reverse Hill-Sachs lesion was elevated und supplemented with the bone core that accrues during drilling of the nail entrance. In the follow-up period good fragment alignment, persistent joint stability and freedom of pain could be observed. On the basis of this case and the current literature the injury mechanism and potential therapy alternatives are discussed.

[Treatment strategies for chronic glenoid defects following anterior and posterior shoulder dislocation]

OBJECTIVE

Restoration of a stable, pain-free and functional shoulder in chronic glenoid defects following anterior or posterior shoulder dislocations.

INDICATIONS

Anterior glenoid defect: all recurrent or persistent shoulder instabilities in association with chronic glenoid lesions. Posterior glenoid defect: all recurrent or persistent postreposition shoulder instabilities with chronic osseous glenoid defects.

CONTRAINDICATIONS

Brachial plexus injury. Poor glenoid bone stock.

SURGICAL TECHNIQUE

Anterior glenoid defect: exposition of the glenoid through a deltopectoral approach. Glenoid reconstruction by autologous iliac crest graft or coracoid transfer, in cases with progressive joint destruction in combination with shoulder arthroplasty. Posterior glenoid defect: exposition of the glenoid through a modified Brodsky approach from posterolateral. Exposure of the posterior capsule between infraspinatus and teres minor muscles, medial capsulotomy, glenoid reconstruction with auto- or allograft, normally by screw osteosynthesis. Treatment of the often accompanying anterior humeral head defect (reverse Hill-Sachs defect) by transposition of the lesser tubercle (modified from McLaughlin), defect coverage by auto- or allograft, or hemiarthroplasty through an anterior approach. In cases of persisting instability reconstruction of the glenoid defect with autologous graft and, if necessary, by shoulder arthroplasty.

POSTOPERATIVE MANAGEMENT

To preserve reconstructed anatomy, a Gilchrist sling is required in anterior reconstructions for 4-6 weeks. For postoperative treatment of posterior defects a thorax abduction splint is recommended for 6 weeks. Active-assisted reduced range of motion exercise is provided under physiotherapeutic guidance according to the individual pathology.

RESULTS

Clinical results following open surgery of chronic glenoid lesions in shoulder instability differ from the treatment results in acute fractures because of the often accompanying large rotator cuff tears, bad bone quality and frequently large defect size. In the hands of experienced shoulder surgeons, however, favorable results can be achieved with modern implants, leading to decisive improvement in patients' quality of life.

[Possibilities for the operative treatment of traumatic posterior shoulder dislocation]

Traumatic posterior locked shoulder dislocation is very rare. The dislocation is often combined with fractures of the humeral head or reversed Hill-Sachs deformities. This case report shows two different possibilities for treatment.