Role of Coracoacromial Ligament and Related Structures in Glenohumeral Stability: A Cadaveric Study
This study sought to determine the role of the coracoacromial ligament and related arch structures in glenohumeral joint stabilization. Eight fresh-frozen cadaver specimens were tested at multiple angles of glenohumeral abduction and rotation for translations (in the direction of and perpendicular to a 50-N force) in intact, vented shoulders and after three interventions: coracoacromial veil release, coracoacromial ligament release, and anterior acromioplasty. After releasing the veil, an inferior force significantly increased inferior translation at lower angles of abduction with no additional increase after coracoacromial ligament section or acromioplasty. After ligament release or acromioplasty, a superior force increased superior translation at all angles. Few increases in anterior or posterior translations were observed. The coracoacromial veil interacts with the structures of the coracoacromial arch and glenohumeral capsule to limit inferior humeral translation. Likewise, the coracoacromial ligament and the acromian serve to limit superior translation. Attempts to preserve these structures may help improve surgical outcomes.
Available from: Mickael Begon
- "Though more active during elevation with arm external rotation, rotator cuff muscles may generate insufficient downward shear forces to counteract the upward shear forces generated by deltoid muscles and minimize upward translation. Moreover, other factors such as capsule (Ishihara et al., 2014) and ligaments (Moorman et al., 2012) are known to limit glenohumeral translations. Consequently , only electromyography-based evidences may be insufficient to provide recommendations for shoulder rehabilitation exercises. "
Available from: Fabien Dal Maso
[Show abstract] [Hide abstract]
ABSTRACT: Glenohumeral translations have been mainly investigated during static poses while shoulder rehabilitation exercises, activities of daily living, and sports activities are dynamic. Our objective was to assess glenohumeral translations during shoulder rehabilitation exercises, activities of daily living, and sports activities to provide a preliminary analysis of glenohumeral arthrokinematics in a broad range of dynamic tasks.
Glenohumeral translations were computed from trajectories of markers fitted to intracortical pins inserted into the scapula and the humerus. Two participants (P1 and P2) performed full range-of-motion movements including maximum arm elevations and internal-external rotations rehabilitation exercises, six activities of daily living, and five sports activities.
During range-of-motion movements, maximum upward translation was 7.5mm (P1) and 4.7mm (P2). Upward translation during elevations was smaller with the arm internally (3.6mm (P1) and 2.9mm (P2)) than neutrally (4.2mm (P1) and 3.7mm (P2)) and externally rotated (4.3mm (P1) and 4.3mm (P2)). For activities of daily living and sports activities, only anterior translation during reach axilla for P1 and upward translation during ball throwing for P2 were larger than the translation measured during range-of-motion movements (108% and 114%, respectively).
While previous electromyography-based studies recommended external rotation during arm elevation to minimize upward translation, measures of glenohumeral translations suggest that internal rotation may be better. Similar amplitude of translation during ROM movement and sports activities suggests that large excursions of the humeral head may be caused not only by fast movements, but also by large amplitude movements.
Copyright © 2015 Elsevier Ltd. All rights reserved.
[Show abstract] [Hide abstract]
ABSTRACT: The benefits of acromioplasty in treating rotator cuff disease have been debated. We systematically reviewed the literature regarding whether acromioplasty with concomitant coracoacromial (CA) release is necessary for the successful treatment of full-thickness rotator cuff tears.
We identified randomized controlled trials that reported on patients who underwent rotator cuff repair with or without acromioplasty and used descriptive statistics to summarize the findings.
Four studies fulfilled the inclusion criteria. They reported on 354 patients (mean age, 59 years; range 3-81 years) with a mean follow-up of 22 months (range 12-24 months). There were two level-I and two level-II studies. Two studies compared rotator cuff repair with versus without acromioplasty, and two studies compared rotator cuff repair with versus without subacromial decompression (acromioplasty, CA ligament resection, and bursectomy). The procedures were performed arthroscopically, and the CA ligament was released in all four studies. There were no statistically significant differences in clinical outcomes between patients treated with acromioplasty compared with those treated without acromioplasty.
This systematic review of the literature does not support the routine use of partial acromioplasty or CA ligament release in the surgical treatment of rotator cuff disease. In some instances, partial acromioplasty and release of the CA ligament can result in anterior escape and worsening symptoms. Further research is needed to determine the optimum method for the operative treatment of full-thickness rotator cuff tears.
Level I, systematic review of level I and II studies.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.