Acromioclavicular joint instability on cross-body adduction view: the biomechanical effect of acromioclavicular and coracoclavicular ligaments sectioning.

Background: The acromioclavicular (AC) and coracoclavicular (CC) ligaments are important stabilizers of the AC joint. We hypothesized that AC and trapezoid ligament injuries induce AC joint instability and that the clavicle can override the acromion on cross-body adduction view even in the absence of conoid ligament injury. Accordingly, we investigated how sectioning the AC and CC ligaments contribute to AC joint instability in the cross-body adduction position.

Usefulness of ultrasound in diagnosing long head of the biceps tendon malposition in patients with rotator cuff tears.

Purpose: This study aimed to determine the role of preoperative shoulder ultrasonography (SUS) in detecting positional abnormalities of the long head of the biceps tendon (LHBT) and predicting subscapularis (SSC) tears in patients with rotator cuff injuries.

Methods: A total of 331 patients (365 shoulders) who had undergone arthroscopic shoulder surgery for the treatment of rotator cuff tears were included in the study. Their preoperative SUS and magnetic resonance imaging (MRI) findings were examined retrospectively to assess the presence of LHBT abnormalities at the bicipital groove.

Arthroscopic Lunate Excision Provides Excellent Outcomes for Low-Demand Patients with Advanced Kienböck's Disease.

Purpose: To examine the clinical outcomes of arthroscopic lunate excisions for advanced Kienböck's disease.

Methods: Fifteen patients (six men and nine women; mean age: 65 years; range: 48-83 years) with advanced Kienböck's disease, who underwent arthroscopic lunate resection between April 2008 and March 2016, were reviewed clinically and radiographically after a follow-up of >2 years (mean: 29 months; range: 24-60 months). Clinical parameters, such as wrist range of motion, grip strength, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and patient-rated wrist evaluation (PRWE) score were evaluated.

The Role of the Acromioclavicular Ligament in Acromioclavicular Joint Stability: A Cadaveric Biomechanical Study.

Background: Acromioclavicular (AC) joint dislocation is evaluated using the radiologically based Rockwood classification. The relationship between ligamentous injury and radiological assessment is still controversial.

Purpose/hypothesis: To investigate how the AC ligament and trapezoid ligament biomechanically contribute to the stability of the AC joint using cadaveric specimens.

New System for the Classification of Epiphyseal Separation of the Coracoid Process: Evaluation of Nine Cases and Review of the Literature.

. Epiphyseal separation of the coracoid process (CP) rarely occurs in adolescents. In this retrospective case series, we reviewed the data of nine patients treated at our center and those of 28 patients reported in the literature.

Glenoid bone resorption after Bankart repair: finite element analysis of postoperative stress distribution of the glenoid.

Background: There are various modifications of the Bankart repair, and postoperative changes to the glenoid morphology after the repair are reported. Among the various procedures performed, a decrease in the lateral glenoid diameter might be related to the surgery that involves removal of the articular cartilage and repair of the labrum-anterior inferior glenohumeral ligament complex on the glenoid surface. This is in contrast to cases without significant bony Bankart lesions that are not on the edge of the glenoid.

Humeral bone resorption after reverse shoulder arthroplasty using uncemented stem.

Background: Humeral stem loosening has gained attention as it has been identified as a cause of revision surgery in reverse shoulder arthroplasty (RSA). In RSA, humeral stem revision is very difficult if there is humeral bone loss because of stress shielding. Some studies of humeral bone resorption after anatomic shoulder arthroplasty have been published, but there are few detailed reports of humeral bone resorption after RSA.