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Updated: Dec 23, 2025

Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
Shoulder Conditions: Clavicle and Acromioclavicular Joint Conditions
Karin VanBaak1, Jill Tirabassi2, Giselle Aerni3
1UCHealth Family Medicine Clinic - Boulder, 5495 Arapahoe Ave, Boulder, CO 80303.
Abstract:
The clavicle is the most commonly fractured bone, and the most frequently fractured part of the clavicle is the middle third (ie, midshaft). X-ray usually is the first-line imaging modality for clavicle injuries. Conservative management is preferred for patients with uncomplicated and nondisplaced clavicular fractures. Typically, immobilization should last 4 weeks, then range-of-motion exercises should begin after 4 weeks, with full return to activities by 12 weeks. Distal clavicle osteolysis is a relatively uncommon pathologic bone resorption that occurs with repetitive overhead activities. Conservative management includes activity modification, nonsteroidal anti-inflammatory drugs, and injection. Surgical options also are available. Acute acromioclavicular (AC) joint injuries usually are the result of a direct blow to the superolateral shoulder with the humerus in adduction. The Rockwood classification system of AC joint injuries describes types I to VI, classified by the ligaments injured and degree of displacement. Low-grade AC joint injuries (ie, types I to III) typically can be managed nonsurgically, whereas high-grade injuries are managed with surgery. Osteoarthrosis of the AC joint manifests similarly to distal clavicle osteolysis and may be posttraumatic or idiopathic. Osteoarthrosis typically is managed with activity modification, nonsteroidal anti-inflammatory drugs, and injections but also may be managed surgically.
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