Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (924 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
The gliding joint formed by the outer extremity of the clavicle and the inner margin of the acromion process of the scapula.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Acromioclavicular Joints; Joint, Acromioclavicular; Joints, Acromioclavicular; Coracoacromial Ligament; Coracoacromial Ligaments; Ligament, Coracoacromial; Ligaments, Coracoacromial; Coracoacromial Arch.
Where it fits in the MeSH classification
- Broader topics
- Joints
Related concepts
Research landscape
PubMed indexes 2,564 records tagged with the MeSH heading “Acromioclavicular Joint” (counts retrieved 2026-10-31). 491 of them (19.1%) were published from 2020 onward, and the busiest period so far is through 1999 with 821 records.
Reviews account for 309 records (12.1%) and meta-analyses for 29. Randomized controlled trials number 50 (2.0%) as a share of all records on the topic. Randomized trials make up only a small share of this literature, so much of what is known comes from laboratory, observational or descriptive work.
Show the data
| Period | Records |
|---|---|
| through 1999 | 821 |
| 2000-2009 | 446 |
| 2010-2019 | 806 |
| 2020 onward | 491 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 309 | 12.1% |
| Meta-analyses | 29 | 1.1% |
| Randomized controlled trials | 50 | 2.0% |
Method: PubMed query "Acromioclavicular Joint"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-31.
Reading the evidence in anatomy and physiology
Anatomy describes how body structures are built and physiology describes how they normally work, so most findings here are descriptive or mechanistic rather than evidence about treatment. Much of what is known comes from dissection, imaging, tissue studies and experiments in animals, and measurements in healthy volunteers can differ from those in people with disease or at different ages. Normal ranges vary between individuals and populations. Check whether a result was measured in people or in another species, the age and health of the participants, and the method used.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Current concepts in acromioclavicular joint (AC) instability - a proposed treatment algorithm for acute and chronic AC-joint surgery | 2022 | Review article Design not recorded in structured metadata | 69 | cc by PMID 36494652 · DOI · PMC9733089 |
| Comparison of surgical and conservative treatment of Rockwood type-III acromioclavicular dislocation: A meta-analysis | 2018 | Meta-analysis Design not recorded in structured metadata | 52 | cc by PMID 29369191 · DOI · PMC5794375 |
| Management of chronic unstable acromioclavicular joint injuries | 2017 | Review article Design not recorded in structured metadata | 42 | cc by PMID 28275882 · DOI · PMC5685976 |
| Acromioclavicular dislocation associated with fracture of the coracoid process: a series of cases and review of the literature | 2025 | Review article Design not recorded in structured metadata | 8 | cc by PMID 39992382 · DOI · PMC12003561 |
Current concepts in acromioclavicular joint (AC) instability - a proposed treatment algorithm for acute and chronic AC-joint surgery [1]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundThere exists a vast number of surgical treatment options for acromioclavicular (AC) joint injuries, and the current literature has yet to determine an equivocally superior treatment.
- Closing excerpt
- ConclusionFuture research should focus on addressing horizontal and rotational instability, to restore native physiological and biomechanical properties of the AC joint.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (274 words)
BackgroundThere exists a vast number of surgical treatment options for acromioclavicular (AC) joint injuries, and the current literature has yet to determine an equivocally superior treatment. AC joint repair has a long history and dates back to the beginning of the twentieth century.Main bodySince then, over 150 different techniques have been described, covering open and closed techniques. Low grade injuries such as Type I-II according to the modified Rockwood classification should be treated conservatively, while high-grade injuries (types IV-VI) may be indicated for operative treatment. However, controversy exists if operative treatment is superior to nonoperative treatment, especially in grade III injuries, as functional impairment due to scapular dyskinesia or chronic pain remains concerning following non-operative treatment. Patients with a stable AC joint without overriding of the clavicle and without significant scapular dysfunction (Type IIIA) may benefit from non-interventional approaches, in contrast to patients with overriding of the clavicle and therapy-resistant scapular dysfunction (Type IIIB). If these patients are considered non-responders to a conservative approach, an anatomic AC joint reconstruction using a hybrid technique should be considered. In chronic AC joint injuries, surgery is indicated after failed nonoperative treatment of 3 to 6 months. Anatomic AC joint reconstruction techniques along with biologic augmentation (e.g. Hybrid techniques, suture fixation) should be considered for chronic high-grade instabilities, accounting for the lack of intrinsic healing and scar-forming potential of the ligamentous tissue in the chronic setting. However, complication and clinical failure rates remain high, which may be a result of technical failures or persistent horizontal and rotational instability.ConclusionFuture research should focus on addressing horizontal and rotational instability, to restore native physiological and biomechanical properties of the AC joint.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 36494652 · DOI · PMC9733089
Comparison of surgical and conservative treatment of Rockwood type-III acromioclavicular dislocation: A meta-analysis [2]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundThere is no consensus on the effects of surgical versus conservative treatment on Rockwood type-III dislocation of the acromioclavicular joint in general orthopedic practice.
- Closing excerpt
- However, there was no statistical difference between operative and nonoperative treatment in terms of clinical outcomes.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (257 words)
BackgroundThere is no consensus on the effects of surgical versus conservative treatment on Rockwood type-III dislocation of the acromioclavicular joint in general orthopedic practice. The objective of this meta-analysis was to compare the clinical outcomes of patients managed surgically and conservatively following type-III acromioclavicular (AC) dislocation.MethodsThe Cochrane Library, EMBASE, MEDLINE via Ovid SP, and PubMed databases were searched for randomized controlled trials and observational studies. Patient data were pooled using standard meta-analytic approaches. For continuous variables, the weighted mean difference was used. For dichotomous data, the odds ratio was calculated.ResultsThe current analysis included 10 trials on this topic, and the results demonstrated that there were no significant differences between surgical and conservative treatment in terms of pain, weakness, tenderness, post-traumatic arthritis, restriction of strength, unsatisfactory function, and scores (Constant, UCLA, Imatani, SST, DASH, Larsen). Analyses of ossification of the coracoclavicular ligament (OR = 1.62, 95% CI = 1.01-2.61) and osteolysis of the lateral clavicle (OR = 2.87, 95% CI = 1.27-6.52) suggested better function with conservative treatment versus surgical treatment, but the latter was superior to conservative treatment with regard to loss of anatomic reduction. Only 1 study showed a higher acromioclavicular joint instability score for surgical management compared with conservative management (P ConclusionIn the management of Rockwood type-III AC dislocation, conservative treatment is superior to surgical treatment. Nonoperative treatment results in a lower incidence of ossification of the coracoclavicular ligament and osteolysis of the lateral clavicle compared with operative treatment. However, there was no statistical difference between operative and nonoperative treatment in terms of clinical outcomes.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 29369191 · DOI · PMC5794375
Management of chronic unstable acromioclavicular joint injuries [3]
Abstract reading summary — source excerpts
- Opening excerpt
- The acromioclavicular joint represents the link between the clavicle and the scapula, which is responsible for the synchronized dynamic of the shoulder girdle.
- Closing excerpt
- Level of evidenceExpert opinion, Level V.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (134 words)
The acromioclavicular joint represents the link between the clavicle and the scapula, which is responsible for the synchronized dynamic of the shoulder girdle. Chronic acromioclavicular joint instability involves changes in the orientation of the scapula, which provokes cinematic alterations that might result in chronic pain. Several surgical strategies for the management of patients with chronic and symptomatic acromioclavicular joint instability have been described. The range of possibilities includes anatomical and non-anatomical techniques, open and arthroscopy-assisted procedures, and biological and synthetic grafts. Surgical management of chronic acromioclavicular joint instability should involve the reconstruction of the torn ligaments because it is accepted that from three weeks after the injury, these structures may lack healing potential. Here, we provide a review of the literature regarding the management of chronic acromioclavicular joint instability.Level of evidenceExpert opinion, Level V.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 28275882 · DOI · PMC5685976
Acromioclavicular dislocation associated with fracture of the coracoid process: a series of cases and review of the literature [4]
Abstract reading summary — source excerpts
- Opening excerpt
- PurposeComplete acromioclavicular (AC) dislocation associated with fracture of the coracoid process (CP) is uncommon.
- Closing excerpt
- Multiple approaches have been opted for by surgeons to deal with this combined injury and are the basis of this review.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (259 words)
PurposeComplete acromioclavicular (AC) dislocation associated with fracture of the coracoid process (CP) is uncommon. The strong coracoclavicular ligaments, instead of rupture, may avulse the CP near its base, and with disruption of the AC joint may allow complete dislocation of the clavicle. We report ten cases, one of the largest series in literature, and reviewed the findings and treatment previous reported cases, to allow potential readers to establish the most appropriate treatment.MethodsWe have prospectively collected those cases in which we had identified an association of an AC dislocation with a fracture of the CP, as well as retrospectively reviewed the records that were coded as AC dislocations and CP fracture looking for this association in the senior author institutions. A literature search was completed on PubMed, Web of Science and Scholar Google, using a sensitive search strategy.ResultsWe have collected a total of ten patients with the association of a CP fracture to an AC dislocation in a period of twenty-five years. A review of the cases reported in literature shows a great variability in treatment methods from conservative to more surgically in recent years.ConclusionsWhen an AC dislocation is identified by clinical examination and X-rays, one should be aware of a possible fracture of the CP. It is possible this association to be more frequent than shown in literature because of the CP fracture can easily be missed out or mistaken with an unfussed epiphysis in routine anteroposterior radiography. Multiple approaches have been opted for by surgeons to deal with this combined injury and are the basis of this review.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 39992382 · DOI · PMC12003561
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article Evaluation and treatment of acromioclavicular joint injuries [5]
- Research article Current concepts in the treatment of acromioclavicular joint dislocations [6]
- Research article Shoulder function: the perfect compromise between mobility and stability [7]
- Research article ISAKOS upper extremity committee consensus statement on the need for diversification of the Rockwood classification for acromioclavicular joint injuries [8]
- Research article Acromioclavicular joint injuries: diagnosis and management [9]
- Research article Current Concepts in the Operative Management of Acromioclavicular Dislocations: A Systematic Review and Meta-analysis of Operative Techniques [10]
References
- Berthold DP, Muench LN, Dyrna F, Mazzocca AD, Garvin P, Voss A, et al.. Current concepts in acromioclavicular joint (AC) instability - a proposed treatment algorithm for acute and chronic AC-joint surgery. . 2022. PMID 36494652 · DOI · PMC9733089
- Tang G, Zhang Y, Liu Y, Qin X, Hu J, Li X. Comparison of surgical and conservative treatment of Rockwood type-III acromioclavicular dislocation: A meta-analysis. . 2018. PMID 29369191 · DOI · PMC5794375
- Cisneros LN, Reiriz JS. Management of chronic unstable acromioclavicular joint injuries. . 2017. PMID 28275882 · DOI · PMC5685976
- Combalia A, Combalia M, Muñoz-Mahamud E. Acromioclavicular dislocation associated with fracture of the coracoid process: a series of cases and review of the literature. . 2025. PMID 39992382 · DOI · PMC12003561
- Mazzocca AD, Arciero RA, Bicos J. Evaluation and treatment of acromioclavicular joint injuries. Am J Sports Med. 2007. PMID 17251175 · DOI
- Beitzel K, Cote MP, Apostolakos J, Solovyova O, Judson CH, Ziegler CG, et al.. Current concepts in the treatment of acromioclavicular joint dislocations. Arthroscopy. 2013. PMID 23369483 · DOI
- Veeger HE, van der Helm FC. Shoulder function: the perfect compromise between mobility and stability. J Biomech. 2007. PMID 17222853 · DOI
- Beitzel K, Mazzocca AD, Bak K, Itoi E, Kibler WB, Mirzayan R, et al.. ISAKOS upper extremity committee consensus statement on the need for diversification of the Rockwood classification for acromioclavicular joint injuries. Arthroscopy. 2014. PMID 24485119 · DOI
- Simovitch R, Sanders B, Ozbaydar M, Lavery K, Warner JJ. Acromioclavicular joint injuries: diagnosis and management. J Am Acad Orthop Surg. 2009. PMID 19307670 · DOI
- Gowd AK, Liu JN, Cabarcas BC, Cvetanovich GL, Garcia GH, Manderle BJ, et al.. Current Concepts in the Operative Management of Acromioclavicular Dislocations: A Systematic Review and Meta-analysis of Operative Techniques. Am J Sports Med. 2019. PMID 30272997 · DOI
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-31.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.