Acromioclavicular Joint Stabilisation / Reconstruction — Operative Rationale & Post-operative Rehabilitation (Evidence)

Topic scope: Post-operative rehabilitation after acromioclavicular (AC) joint stabilisation / reconstruction for a high-grade AC joint dislocation (Rockwood type III–V) — restoring the alignment between the clavicle and scapula with a coracoclavicular (CC) suspensory device (suture-button / endobutton construct), with or without a biological tendon graft (semitendinosus / pectoralis minor) and with or without a direct AC ligament reconstruction. This page also summarises the operative/non-operative evidence that frames the rehabilitation choices. It is the clinician-facing companion to the patient protocol.

Defining principle of the surgical rehab here — PROTECT the construct. Unlike a capsular release (where the enemy is re-stiffening and rehab is immediate aggressive ROM), AC joint stabilisation is a protect-the-repair pathway, closer in spirit to a rotator-cuff or instability repair. The reconstruction has to resist the constant downward pull of gravity on the weight of the arm — the exact deforming force that displaced the joint in the first place. A suspensory suture-button or tendon graft has no early intrinsic strength; biological healing of the CC/AC ligaments and tunnel incorporation takes weeks to months, and the dominant early complication is loss of reduction before that healing matures. So the rehab is deliberately conservative: the sling carries the weight of the arm (typically ~6 weeks), active elevation and any downward traction on the arm are avoided early, ROM is restricted (no elevation > 90°, no cross-body, no reaching behind the back) for the first 6 weeks, strengthening waits until the construct has matured (~12 weeks), and return to contact/collision sport is deferred to ~4–6 months. Motion progression and protection are the two levers; the single most important point distinguishing this protocol from the capsular-release inversion is that here, time and protection are the friends, not the enemy.

A. THE OPERATION & WHY REHAB IS PROTECTIVE

A high-grade AC dislocation tears the AC and coracoclavicular (conoid + trapezoid) ligaments, allowing the clavicle to rise relative to the acromion under the weight of the arm. Surgical stabilisation aims to restore the CC distance and let the ligaments heal in a reduced position. Contemporary constructs are predominantly:

• CC suspensory fixation — a suture-button / endobutton loop passed through clavicular and coracoid tunnels (e.g. flip-button, single- or double-tunnel). Restores vertical stability.
• + Biological augmentation — a free tendon graft (semitendinosus allograft/autograft, or the pectoralis minor / coracoacromial ligament in Weaver–Dunn-type procedures) to reconstruct the CC ± AC ligaments. The anatomy of the pectoralis minor tendon has been characterised specifically for this use [pec minor anatomy, JSES 2007].
• + Direct AC reconstruction — adding an AC-level construct to the CC reconstruction improves horizontal stability; combined CC + AC reconstruction gives better radiographic reduction and lower reoperation rates than isolated CC reconstruction in pooled data.

The structural properties of the reconstructed CC complex have been measured biomechanically: reconstructions restore much, but not all, of the intact ligament's stiffness and load to failure [Structural Properties, Am J Sports Med 2000]. This is the mechanical basis for protecting the construct early — the graft/button is weaker than the native ligament until it heals and incorporates.

B. EVIDENCE BY THEME

1. Operative vs non-operative — only high grades benefit from surgery

• Type I–II AC injuries are managed non-operatively. Type III is genuinely controversial and most are treated non-operatively first; type IV–V are the usual operative indications [ACJ Injuries: Evidence-based Treatment, JAAOS 2018]. A network meta-analysis of RCTs for acute Rockwood III–V found no single surgical technique clearly superior, and that surgery's advantage over non-operative care is modest and grade-dependent [network MA, JSES 2023].
• Hook-plate fixation of acute dislocations improved radiographic but NOT clinical outcomes versus non-operative treatment [Hook-plate RCT, JBJS 2017] — a caution that radiographic reduction does not automatically translate into a better patient outcome, and a reason the hook plate (which requires removal) is not the preferred construct here.
• The Rockwood classification itself has only moderate reliability between observers [Rockwood reliability, JSES 2021], which is part of why type III decision-making is debated.

2. Loss of reduction is the dominant complication — and it shapes the rehab

• Loss of reduction (the clavicle drifting back up) is the most frequent radiographic failure after suspensory-device stabilisation. Clavicular tunnel widening correlates with post-operative loss of reduction in an implant-dependent way [tunnel widening, Arthroscopy 2023] — i.e. the construct and tunnel position matter.
• Radiographic failure and reoperation rates after ACJ reconstruction are non-trivial [radiographic failure / reoperation, Bone Joint J 2016]; one suspensory-device series reported ~10–11% revision for loss of reduction / implant failure (suture fatigue, button escape, coracoid stress fracture, deep infection) [web: suspensory-device cohort].
• Adding the AC-level reconstruction and a biological graft improves radiographic reduction and lowers reoperation versus isolated CC suture-button [web: combined CC+AC reviews].
• Complications after operative treatment of high-grade injuries are well catalogued [complications, JSES 2023] — they include loss of reduction, coracoid/clavicle fracture, hardware problems and infection.

Rehab implication: because the early failure mode is mechanical loss of reduction under arm-weight loading, the early phase forbids active elevation, lifting, downward traction on the arm and weight-bearing through the arm — the patient protects the construct while the ligaments and tunnels heal.

3. Outcomes and return to sport are generally good — but timeline is conservative

• Anatomic CC reconstruction with semitendinosus graft for chronic dislocation gives good clinical and radiological results [semitendinosus reconstruction, KSSTA 2020].
• Sports activity after anatomic flip-button stabilisation is generally restored, with most athletes returning to their pre-injury sport, though return is gradual [flip-button sport, KSSTA 2016].
• Delayed (chronic) reconstruction with a modern suspensory device does not increase fixation failure or major complications versus acute fixation [web: delayed reconstruction].

4. The rehab protocol itself is consensus/expert, not RCT-derived — and it is highly variable

A systematic review of publicly available ACJ-reconstruction rehabilitation protocols found they are widely variable: sling duration ranged 3–8 weeks (the modal recommendation was 6 weeks, in 8/18 protocols), active ROM commonly began at ~6 weeks (6/20 protocols), and heavy/strenuous shoulder use was typically prohibited for a further ~6 weeks beyond the initial 6-week protection period [Cheema et al., Arthrosc Sports Med Rehabil 2021]. There is no high-level RCT defining the optimal post-op regimen — phase timings are expert/consensus.

The patient protocol's phase boundaries (0–6 / 6–12 / 12–18 weeks, sling 6 weeks, return to contact sport ~4–6 months) sit squarely within this published range and match the Massachusetts General Brigham / MGH Sports Medicine ACJ-reconstruction guideline (Phase I 0–6 wk, Phase II 7–12 wk, Phase III 13–18 wk) and similar surgeon protocols (e.g. Dickens: 6-week sling, return to all activity months 4–6).

C. PHASED POST-OP TIMELINE (consistent with the patient protocol)

(Phase boundaries from the MGH/Mass General Brigham ACJ-reconstruction guideline; return-to-sport windows from the flip-button sport series and surgeon protocols; all within the variability documented by Cheema et al. 2021.)

D. KEY CONTROVERSIES / EVIDENCE QUALITY

1. Type III — operate or not? The most-debated grade; most are trialled non-operatively first. No clear winner in RCT-level data, compounded by only-moderate reliability of the Rockwood grade itself. Moderate / conflicting.
2. Which construct? Network MA shows no single technique clearly superior for acute III–V. Combined CC + AC reconstruction (± graft) gives better radiographic reduction and lower reoperation than isolated CC suture-button, but at the cost of complexity. Hook plates improve radiographs but not clinical scores and need removal. Moderate.
3. Loss of reduction vs clinical outcome. Radiographic loss of reduction is common yet often clinically well-tolerated — radiographic and patient-reported outcomes diverge. This tempers how aggressively reduction should be chased. Moderate.
4. The rehab protocol is consensus, not trial-derived, and published protocols vary widely (sling 3–8 wk; Cheema 2021). The patient page's timings are typical, not RCT-validated. Weak / consensus.

E. EVIDENCE-STRENGTH FLAGS (summary)

• STRONG (RCT / SR-MA): hook-plate improves radiographic but not clinical outcomes vs non-operative (RCT, JBJS 2017); network meta-analysis of RCTs for acute III–V shows no clearly superior technique (JSES 2023).
• MODERATE (cohorts / biomechanical / SR): anatomic semitendinosus CC reconstruction outcomes (KSSTA 2020); sports return after flip-button stabilisation (KSSTA 2016); loss-of-reduction / tunnel-widening drivers (Arthroscopy 2023; Bone Joint J 2016); complications of high-grade operative treatment (JSES 2023); reconstructed-CC biomechanics (AJSM 2000); combined CC+AC > isolated CC for reduction/reoperation; delayed reconstruction safety.
• WEAK / CONSENSUS ONLY: the post-operative rehabilitation protocol itself — no defining RCT; protocols are expert/consensus and highly variable (Cheema 2021; sling 3–8 wk). Rockwood classification reliability only moderate (JSES 2021).

CITATIONS

RAG corpus (180,000+ Orthopaedic articles)

• Anatomy of the pectoralis minor tendon and its use in acromioclavicular joint reconstruction. J Shoulder Elbow Surg. 2007. DOI: 10.1016/j.jse.2006.09.007
• Clavicular tunnel widening after acromioclavicular stabilization shows implant-dependent correlation with postoperative loss of reduction. Arthroscopy. 2023. DOI: 10.1016/j.arthro.2023.05.014
• Acromioclavicular joint injuries: evidence-based treatment. J Am Acad Orthop Surg. 2018. DOI: 10.5435/jaaos-d-17-00105
• Review of Weaver and Dunn on treatment of acromioclavicular injuries, especially complete acromioclavicular separation. J ISAKOS. 2019. DOI: 10.1136/jisakos-2019-000299
• Structural properties of the intact and the reconstructed coracoclavicular ligament complex. Am J Sports Med. 2000. DOI: 10.1177/03635465000280010201
• Complications after operative treatment of high-grade acromioclavicular injuries. J Shoulder Elbow Surg. 2023. DOI: 10.1016/j.jse.2023.03.019
• Sports activity after anatomic acromioclavicular joint stabilisation with flip-button technique. Knee Surg Sports Traumatol Arthrosc. 2016. DOI: 10.1007/s00167-016-4287-7
• Anatomic reconstruction of the coracoclavicular and acromioclavicular ligaments with semitendinosus tendon graft for the treatment of chronic acromioclavicular joint dislocation provides good clinical and radiological results. Knee Surg Sports Traumatol Arthrosc. 2020. DOI: 10.1007/s00167-020-06285-x
• Hook-plate fixation in patients with acute acromioclavicular joint dislocation improved radiographic but not clinical outcomes compared with nonoperative treatment. J Bone Joint Surg Am. 2017. DOI: 10.2106/jbjs.16.00582
• Radiographic failure and rates of re-operation after acromioclavicular joint reconstruction. Bone Joint J. 2016. DOI: 10.1302/0301-620x.98b4.35935
• Treatment options for acute Rockwood type III–V acromioclavicular dislocations: a network meta-analysis of randomized controlled trials. J Shoulder Elbow Surg. 2023. DOI: 10.1016/j.jse.2023.01.039
• A relook at the reliability of Rockwood classification for acromioclavicular joint injuries. J Shoulder Elbow Surg. 2021. DOI: 10.1016/j.jse.2021.01.016

Literature (URLs)

• Cheema SG, Hermanns C, Coda RG, et al. Publicly accessible rehabilitation protocols for acromioclavicular joint reconstruction are widely variable. Arthrosc Sports Med Rehabil. 2021;3(2):e427–e433. https://doi.org/10.1016/j.asmr.2020.10.007 (sling 3–8 wk, modal 6 wk; active ROM ~6 wk; further ~6 wk before heavy use)
• Acromioclavicular joint injuries: effective rehabilitation (review). PMC. https://pmc.ncbi.nlm.nih.gov/articles/PMC8169819/
• Delayed acromioclavicular joint reconstruction using a modern tunnelled suspensory device does not increase the risk of fixation failure or major complications. PubMed. https://pubmed.ncbi.nlm.nih.gov/35781084/
• Low rate of substantial loss of reduction immediately after hardware removal following ACJ stabilization using a suspensory fixation system. KSSTA. https://link.springer.com/article/10.1007/s00167-022-06978-5
• Minimum 10-year outcomes after arthroscopically assisted anatomic coracoclavicular ligament reconstruction for type III and V AC joint injuries. ScienceDirect. https://www.sciencedirect.com/science/article/pii/S2666638325001835

Published rehab protocols (URLs — basis for the phase structure)

• Massachusetts General Brigham Sports Medicine. Rehabilitation guideline for acromioclavicular joint reconstruction (including coracoclavicular ligament reconstruction). https://www.massgeneral.org/assets/MGH/pdf/orthopaedics/sports-medicine/physical-therapy/rehabilitation-protocol-for-acromioclavicular-joint-reconstruction.pdf (Phase I 0–6 wk sling, Phase II 7–12 wk, Phase III 13–18 wk)
• Dickens JD. AC joint reconstruction protocol (Duke Sports Medicine). https://www.jondickensmd.com/pdf/ac-joint-reconstruction-protocol.pdf (6-week sling worn for sleep; return to all activity months 4–6)
• Chambler A. ACJ stabilisation rehabilitation guidelines. https://www.andrewchambler.com/post/acj-stabilisation-rehabilitation-guidelines
• North Tees and Hartlepool NHS Foundation Trust. Acromioclavicular joint stabilisation — LockDown/Weaver Dunn procedure. https://www.nth.nhs.uk/resources/acromioclavicular-joint-stabilisation-lockdown-weaver-dunn-procedure/
• Stone Clinic. Acromioclavicular (AC) joint reconstruction rehab protocol. https://www.stoneclinic.com/Acromioclavicular-AC-joint-reconstruction-rehab-protocol