Upper Limb Muscles
Eve K. Boyle, Vondel S. E. Mahon, Rui Diogo in Handbook of Muscle Variations and Anomalies in Humans, 2022
Pectoralis minor may arise from the second to fourth ribs (Macalister 1875; Standring 2016). Other origin patterns include the second to fifth ribs, second to fourth ribs, third to fourth ribs, or third to fifth ribs (Macalister 1875; Mori 1964; Standring 2016), or only from the fifth rib in a rare case (Turan-Özdemir and Cankur 2004). An origin from the sixth rib has been observed (Macalister 1875; Bergman et al. 1988). The tendon may cross the coracoid process into the coraco-acromial ligament, or even extend beyond the ligament and attach to shoulder joint capsule or the humerus (Macalister 1875; Knott 1883a; Bergman et al. 1988, Tubbs et al. 2005a; Uzel et al. 2008; Snosek and Loukas 2016; Standring 2016). Other potential attachments include the clavicle, costocoracoid membrane, costohumeral ligament, or the supraspinatus tendon (Macalister 1875; Uzel et al. 2008; Snosek and Loukas 2016).
Surgery of the Shoulder
Timothy W R Briggs, Jonathan Miles, William Aston, Heledd Havard, Daud TS Chou in Operative Orthopaedics, 2020
Imaging should be interrogated for underlying pathology. In particular, radiographs should be assessed to ensure an os acromiale is not present. The arthroscopic pump is set between 30 and 70 mm Hg. The arthroscope is introduced through the posterior portal and a diagnostic arthroscopy performed. It is then introduced into the subacromial bursa. The bursal surface of the cuff is inspected to confirm the presence of an impingement lesion (inflammation, roughening and fibrillation). Next, the undersurface of the acromion is examined for a corresponding ‘kissing’ lesion. The acromion can be further assessed using an arthroscopic probe for any acromial hooks or spurs. The coracoacromial ligament is also inspected. The lateral portal is used for instrumentation. A spinal needle is used for the outside-in technique of portal placement. Although this portal is at the level of the axillary nerve, the nerve is not usually threatened as the instruments are aimed proximally towards the acromion. No cannula is required.
Operative management of acromioclavicular joint injuries
Andreas B. Imhoff, Jonathan B. Ticker, Augustus D. Mazzocca, Andreas Voss in Atlas of Advanced Shoulder Arthroscopy, 2017
Since the first operative treatment for an AC joint injury was reported by Cooper15 in 1861, well over 150 different operative techniques for AC joint injuries have been described.16,17 Initial surgical approaches centered on AC joint fixation using Steinman pins or Kirschner wires to temporarily transfix the AC joint. These constructs were abandoned as a result of high incidences of hardware failure and pin/wire migration.18 In 1917 Cadenat famously secured the CA ligament to the distal clavicle in attempts to re-establish reduction of the AC joint. In 1972, Weaver and Dunn19 described an open treatment of acute and chronic AC injuries via transfer of the coracoacromial ligament from the acromion to the clavicle, with attachment via sutures. This technique has undergone extensive modification and revision in the decades since its introduction in attempts to improves outcomes, most notably the addition of distal clavicle resection to prevent symptomatic arthrosis at the AC joint, and later by the addition of CC fixation via wires, screws, and tissue grafts to further stabilize the repair.20 The major challenge facing this operation has been lasting horizontal stability and maintenance of reduction. Additionally, distally resected clavicles have been found to have significant increases in posterior translation compared to non-resected clavicles.21,22 This is due to the transferred CA ligament lacking the inherent strength of the native CC ligaments and the ability to withstand native forces imposed by normal movements of the upper extremity.
Acromioclavicular joint injuries at a Colorado ski resort
Published in The Physician and Sportsmedicine, 2023
Naomi Kelley, Lauren Pierpoint, Jack Spittler, Morteza Khodaee
Acromioclavicular joint (ACJ) injuries (also known as separations or dislocations) are very common, accounting for up to forty percent of all shoulder injuries [1–4]. The AC joint is a diarthrodial joint where the clavicle can rotate and translate anteriorly, posteriorly and inferiorly in relation to its articulation with the acromion. The joint is composed of a meniscus-type structure of hyaline cartilage, surrounded by synovium [2]. Stability of the ACJ is provided horizontally by the acromioclavicular ligament, and vertically by the coracoacromial ligament. Although not directly attached to the acromion, two coracoclavicular ligaments (conoid and trapezoid ligaments) provide further vertical stability to the joint [5]. Overall, the anatomy of the ACJ provides resistance against significant forces.
Deformation of coracoacromial ligament during overhead movement as an early indicator of subacromial impingement in elite adolescent badminton players
Published in The Physician and Sportsmedicine, 2019
Szu-Heng Wang, Tung-Yang Yu, Yin-Chou Lin, Pei-Chi Liao, Wen-Chung Tsai
Several causes of shoulder pain have been proposed for overhead athletes, among which subacromial impingement syndrome (SAIS) is considered to be the most common [6]. During overhead athletic activities, if the rotator cuff muscles are unable to maintain humeral head within the glenoid fossa due to fatigue or motor control deficits, humeral superior translation may occur, resulting in SAIS [7–9]. Because the subacromial space is bounded superiorly by the acromion and coracoacromial ligament (CAL), impingement of the rotator cuff could also lead to strain and dynamic deformation of the CAL during shoulder movement. In support of this hypothesis, preliminary reports have shown that CAL deformation is indeed more prevalent in persons with shoulder pain or supraspinatus tendon tear [10,11].
Feasibility Analysis and Clinical Applicability of a Modified Type V Resection Method for Malignant Bone Tumors of the Proximal Humerus
Published in Journal of Investigative Surgery, 2020
Qing Liu, Zhibing Dai, Junshen Wu, Suzhi Ji, Jingping Bai, Renbing Jiang
The humerus was truncated at least 5 cm away from the lesion according to the tumor-free principle; then we cut off the humeral shaft using a swing saw or wire saw. With the shoulder joint capsule exposed, we measured a distance of about 4 mm from the medial margin of the articular capsule to the basal outside lateral margin of the coracoid process. In all cases, the medial margin of the articular capsule was visually observed to be unaffected by the tumor. We performed the modified type V resection, resecting the shoulder joint outside the coracoid process, preserving the coracoid process and the coracoacromial ligament. The scapula glenoid fossa was cut at a distance 4 mm from the outside lateral margin of the coracoid process, 15° counterclockwise from the top to the bottom, and then clockwise from the bottom up, creating a nearly concave resection. We completely removed the shoulder joint (including the long-head tendon of the biceps brachii) and the humeral tumor segment.
Related Knowledge Centers
- Acromioclavicular Joint
- Acromion
- Deltoid Muscle
- Supraspinatus Muscle
- Ligament
- Coracoid Process
- Scapula
- Humerus
- Clavicle
- Synovial Bursa