AC Joint Sprain & Shoulder Separation: Conservative Physiotherapy Treatment Guide
Medically Reviewed by Dr. Ponkhi Sharma, PT
Last Updated: April 2026
Overview
An acromioclavicular (AC) joint sprain — commonly called a 'shoulder separation' — is an injury to the ligaments connecting the lateral clavicle (collarbone) to the acromion (the bony shelf extending from the scapula). It is most commonly caused by a direct fall onto the tip of the shoulder or a fall on an outstretched arm. AC joint injuries are graded I–VI using the Rockwood classification, with Grades I–III amenable to conservative physiotherapy and Grades IV–VI typically requiring surgical intervention. AC joint injuries account for approximately 9% of all shoulder injuries, with the highest incidence in cyclists, rugby and football players, and collision sport athletes in Bangalore.
Common Symptoms
- Precise point tenderness directly over the AC joint — the small joint at the very top of the shoulder where the clavicle meets the acromion.
- A visible 'step deformity' at the top of the shoulder — the lateral clavicle riding upward relative to the acromion, creating a prominent bump.
- Pain with horizontal cross-body movements — bringing the arm across the body toward the opposite shoulder (a direct stress test for the AC joint).
- Pain when sleeping on the affected shoulder and with any pressure on the joint.
- Weakness and pain with overhead activities and with reaching across the body.
- A painful clicking sensation at the AC joint with shoulder movement in lower-grade injuries.
Primary Causes
- Direct fall onto the tip of the shoulder — the single most common mechanism, creating a downward force on the acromion while the clavicle remains fixed (bicycle falls, rugby tackles, wrestling).
- Fall onto an outstretched arm — forces transmitted up through the humerus stress the AC joint from an inferior direction.
- Direct blow to the superior shoulder in contact sports — collision from above during tackling or blocking.
- Repetitive overhead loading — contributes to chronic AC joint arthritis and distal clavicle osteolysis (stress resorption at the clavicle tip) in heavy weightlifters.
1. Grading AC Joint Injuries: The Rockwood Classification Explained
Accurate injury grading is the foundation of effective AC joint sprain treatment Bangalore. The Rockwood classification defines six injury grades based on the extent of ligamentous disruption and the degree and direction of clavicular displacement.
Grade I: Sprain (partial tear) of the AC ligament only, with intact coracoclavicular (CC) ligaments. No radiological displacement. Presents with AC joint pain and tenderness but a stable joint on clinical stress testing. Full return to sport in 1–2 weeks with conservative management.
Grade II: Complete rupture of the AC ligament with sprain (partial tear) of the CC ligaments. Slight clavicular elevation on X-ray (typically less than 50% displacement compared to the normal side). A palpable step deformity is present but smaller than Grade III. Treatment is conservative physiotherapy over 4–6 weeks.
Grade III: Complete rupture of both AC and CC ligaments. Significant clavicular elevation on stress X-ray (100% or greater displacement). A prominent step deformity is clearly visible. The management of Grade III is the most debated in shoulder orthopaedics — current high-quality evidence supports conservative physiotherapy as the first-line treatment for the majority of Grade III patients, with equivalent 2-year functional outcomes to surgery.
Grades IV–VI: Involve unusual displacement directions (posterior displacement of the clavicle through the trapezius, inferior displacement, or explosive separation) caused by high-energy trauma. These grades require surgical stabilization and urgent orthopedic referral. Our physiotherapists will immediately identify features suggesting a high-grade injury requiring surgical consultation.
2. Phase 1 — Acute Pain Management & Structural Protection (Weeks 1–3)
The immediate priorities following AC joint injury are pain relief, reduction of local hemorrhage and swelling, and protection of the disrupted ligamentous structures during the critical early healing phase.
Sling for Weight Offloading: A broad-arm sling worn for 1–3 weeks (grade-dependent) supports the weight of the arm, eliminating the downward gravitational pull of the upper limb on the injured AC joint. The arm weight itself (approximately 5% of body weight) acts as a continuous distraction force on the AC joint — the sling removes this load entirely during the early healing phase.
AC Joint Offloading Rigid Strapping: We apply a rigid adhesive strapping (Leukotape P or Elastoplast Sport) with a specifically designed 'clavicle depression' technique — creating a downward force vector on the distal clavicle that mechanically reduces the step deformity and unloads the injured ligaments during daily activities. This taping significantly reduces pain with arm use and allows patients to work and perform daily tasks throughout early rehabilitation.
Cryotherapy Protocol: Ice applied for 15–20 minutes every 2 hours for the first 72 hours to control hemorrhage, limit secondary tissue damage, and reduce swelling. After 72 hours, transition to contrast therapy (alternating warm and cold application) to promote vascular reabsorption of the hematoma.
Early Distal Limb Exercise: Elbow flexion/extension, wrist circles, and grip exercises are prescribed from Day 1 to maintain circulation and prevent distal limb stiffness — all performed without loading the shoulder joint itself.
3. Phase 2 — Mobility Restoration & Dynamic Stabilizer Activation (Weeks 3–6)
Once acute pain is managed and the sling is progressively discontinued, we systematically restore shoulder range of motion and begin activating the muscles that provide dynamic stability to the AC joint.
Graduated Active Range of Motion: We restore shoulder flexion and abduction progressively — beginning with gravity-eliminated positions (arm moving in the horizontal plane, supported on a table surface), then advancing to movements against gravity as pain allows. Horizontal cross-body adduction (the movement that most directly stresses the AC joint by compressing the joint surfaces) is the final movement pattern reintroduced, in the last days of Phase 2.
Rotator Cuff & Deltoid Activation: The deltoid muscle is the primary dynamic stabilizer of the AC joint from below, and the trapezius provides dynamic superior-to-superior control. Both are invariably inhibited by pain and disuse following AC joint injury. We begin with submaximal isometrics and progress to theraband isotonic exercises, prioritizing pain-free activation before progressive loading.
AC Joint Mobilization for Grade I–II Injuries: Gentle accessory mobilizations of the AC joint (anterior-posterior and superior-inferior glides at Grade I–II intensity) help resolve any residual stiffness and restore normal joint mechanics that contribute to the painful clicking reported by many Grade I–II patients.
Postural Correction — Scapular Position and Thoracic Extension: Forward head posture and rounded shoulders markedly increase biomechanical stress on the AC joint with all arm movements. Thoracic extension exercises, scapular retraction and depression drills, and postural cueing are integrated from the earliest appropriate point in rehabilitation.
4. Phase 3 — Progressive Strengthening & Return to Function (Weeks 6–12)
Phase 3 focuses on progressive load increases toward the levels required for full occupational and sporting activity, and on ensuring the AC joint is conditioned to tolerate the specific loading patterns of the patient's activities.
Progressive Upper Limb Resistance Training: A graduated program of theraband and dumbbell exercises for all shoulder muscle groups — rows, overhead press progressions, lateral raises, push-up progressions, and pull-down exercises. Each load increase is monitored for AC joint pain. AC joint tenderness, not time, is the criterion that governs progression speed.
Horizontal Adduction Conditioning: The cross-body movement that directly stresses the AC joint is reintroduced progressively late in Phase 3 with resistance — cable cross-body adduction (starting with very light load and 90° of elevation, progressively increasing load and elevation) and inclined push-up progressions targeting pectoralis and serratus while indirectly loading the AC joint.
Graduated Introduction of Bench Press: The standard bench press — particularly with a wide grip — creates a significant inferior distraction load on the AC joint at the bottom of the movement and is the exercise most commonly associated with AC joint symptom recurrence in recreational athletes. We reintroduce this exercise last, with a specifically narrowed grip width and a partial range of motion in the final weeks of Phase 3.
Distal Clavicle Osteolysis Monitoring: In weightlifters and heavy manual workers with persistent AC joint symptoms beyond 12 weeks — particularly with bench pressing, overhead work, and cross-body movements — distal clavicle osteolysis (stress resorption of the clavicle end, visible on MRI) must be considered. Orthopedic referral for further imaging and possible distal clavicle resection is arranged in these refractory cases.
5. Return to Sport: Clearance Criteria & Protective Strategies
Return-to-sport clearance following AC joint injury is based on objective functional criteria, not time alone. We use the horizontal adduction stress test (pain-free), direct palpation pressure test over the AC joint (pain-free), and sport-specific loading tests to determine readiness.
Grade-Specific Return Timelines: Grade I — full return to contact sport when pain-free, typically 1–2 weeks. Grade II — return to non-contact sport at 4 weeks, contact sport at 6 weeks, subject to meeting clearance criteria. Grade III conservative management — non-contact sport return at 8–10 weeks, contact sport at 10–14 weeks, with protective padding recommended for the remainder of the first season.
Protective AC Joint Padding: A custom-fabricated pad that protects the AC joint from direct impact is strongly recommended for the first season of return to contact sport — particularly for rugby players, cyclists, and any sport involving falls or direct shoulder contact. This significantly reduces the risk of re-injury to the incompletely matured ligamentous healing.
Frequently Asked Questions
Is the bump at the top of my shoulder permanent after an AC joint injury?
In Grade I and minor Grade II injuries, the step deformity largely resolves as swelling settles. In Grade III injuries, the clavicular elevation is typically permanent — the clavicle remains elevated because the coracoclavicular ligaments do not heal back to their original anatomical length. However, this does NOT mean the shoulder won't function normally. The overwhelming majority of Grade III patients achieve full, pain-free shoulder function with physiotherapy despite the cosmetic deformity remaining visible.
Should I have surgery for a Grade III AC joint separation?
Multiple high-quality randomized controlled trials comparing surgery to conservative physiotherapy for Grade III AC joint injuries consistently show equivalent functional outcomes at 2-year follow-up in most patients. Surgery is currently recommended for patients who fail 3–4 months of dedicated conservative management, those with very high occupational overhead demands, or patients with Grade IV–VI injuries involving atypical displacement directions.
When can I go back to cycling or rugby after an AC joint sprain?
Grade I: typically 1–2 weeks when pain-free. Grade II: 4–6 weeks. Grade III conservative management: non-contact return at 8–10 weeks, full contact at 10–14 weeks, subject to meeting pain-free functional criteria. Protective padding over the AC joint is recommended for the remainder of the first contact sport season.
Can I lift weights after an AC joint injury?
Most upper limb exercises can be gradually reintroduced within 6–12 weeks depending on injury grade. The highest-risk exercises — wide-grip bench press, behind-the-neck press, and upright rows — should be either permanently avoided or significantly modified in technique following an AC joint injury. A narrower bench press grip (shoulder-width or slightly inside) and limiting range of motion to the point of AC joint symptom onset are the key long-term technique modifications.
Stop living with AC Joint Sprain & Shoulder Separation
Our targeted physiotherapy protocols typically resolve this in Grade I: 1–2 weeks; Grade II: 4–6 weeks; Grade III (conservative): 8–12 weeks.
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