Sternoclavicular Joint Pain and Instability
This article reviews sternoclavicular instability and pain. See Sternoclavicular Joint for a review of the anatomy. The sternoclavicular joint (SCJ) is inherently unstable. The main stabilisers are the strong extrinsic ligaments, and to a lesser extent the muscular envelope.
Classification of Instability
SCJ instability can be structure or non-structural, and causative factors may be traumatic, atraumatic, neurological, or a combination. Other than an acute first time event, instability may be persistent or recurrent. Dislocations are usually anterior, but can uncommonly be posterior.[1]
Stanmore's triangle system, traditionally used for describing glenohumeral joint instability, has also been used to describe SCJ instability. There are three factors that are represented as points in a triangle: type I traumatic structural, type II atraumatic structure, and type III muscle patterning (neuromuscular) non-structural. The groups exist as a spectrum, and patients can have features of two groups, and/or move to a different pattern. With type I, there is a history of trauma such as SCJ dislocation or medial clavicular fracture. In Type II there is a structural capsular pathology without a history of "macro"-trauma but there may be micro-traumatic change. In type III there is a pathological muscle-pattern with inappropriate activation of the pectoralis major clavicular and sternal parts. This is most noticeable with eccentric overhead activities. Muscle patterning can be difficult to detect.[1]
The spectrum of pathologies affecting the SCJ can be categorised into the three Stanmore instability groups. For type I traumatic structural there is medial clavicular fracture and dislocations (posterior, anterior). For type II atraumatic structural there are the heritable connective tissue disorders causing capsular laxity (e.g. Ehlers Danlos syndrome, Marfan syndrome), short clavicular shape increasing torque on the SCJ, osteoarthritis, inflammatory arthritis, infection, and sternoclavicular hyperostosis syndrome. For type III non-structural there is pathological activation of pectoralis major.[1]
- Characteristics of the Stanmore triangle classification of joint instability[1]
Pathology | Type I: Traumatic structural | Type II: Atraumatic structural | Type III: Muscle patterning, non-structural |
---|---|---|---|
Trauma | Yes | No | No |
Articular surface damage | Yes (e.g. disc or chondral injuries) | Not initially, but occurs when longstanding (disc attrition) | No |
Capsular problem | Yes | Yes | Sometimes |
Laxity | Unilateral | Uni-/bilateral | Often bilateral |
Muscle patterning | Normal | Normal | Abnormal pectoralis major activity |
Treatment | Physiotherapy + often ORIF, SCJ reconstruction | Physiotherapy +/- SCJ reconstruction | Physiotherapy (biofeedback) |
Clinical Assessment
- Posterior dislocation
- Child with medial clavicular physeal or metaphyseal fracture-separation
Resources
See Garcia et al for an open access review on sternoclavicular joint instability.[2] Also an older open access review by Sewell et al.[1]
References
- โ 1.0 1.1 1.2 1.3 1.4 Sewell et al.. Instability of the sternoclavicular joint: current concepts in classification, treatment and outcomes. The bone & joint journal 2013. 95-B:721-31. PMID: 23723264. DOI.
- โ Garcia et al.. Sternoclavicular Joint Instability: Symptoms, Diagnosis And Management. Orthopedic research and reviews 2020. 12:75-87. PMID: 32801951. DOI. Full Text.
Literature Review
- Reviews from the last 7 years: review articles, free review articles, systematic reviews, meta-analyses, NCBI Bookshelf
- Articles from all years: PubMed search, Google Scholar search.
- TRIP Database: clinical publications about evidence-based medicine.
- Other Wikis: Radiopaedia, Wikipedia Search, Wikipedia I Feel Lucky, Orthobullets,