AC JOINT INJURIES IN ATHLETES
Sport-Specific Management | RTP Criteria | Type III Athlete Controversy
ATHLETE-SPECIFIC CONSIDERATIONS
Critical Must-Knows
- Type III controversy: Most athletes can RTP conservatively, surgery NO better at 2 years (RCT)
- RTP criteria: Full ROM, pain-free strength greater than 90% contralateral, sport-specific testing
- Throwing athletes: May benefit from surgery due to biomechanical demands
- Contact sports: Protective padding essential on return, re-injury risk 15-20%
- Hook plate requires removal at 3-4 months - second surgery impacts athlete timeline
Examiner's Pearls
- "80-90% of athletes with Type III RTP successfully with conservative treatment
- "Surgical patients need 6-9 months before contact sport return vs 6-12 weeks conservative
- "Axillary view MANDATORY to exclude Type IV (posterior displacement)
- "Cosmetic deformity does NOT correlate with athletic performance
Clinical Imaging
Imaging Gallery
Critical Athletic AC Joint Exam Points
Type III Athlete Decision
Default to conservative even in athletes. Surgery offers NO advantage at 2 years (CRAC trial). Consider surgery ONLY in: throwing athletes, failed conservative 3-6 months, cosmesis concerns in elite athletes.
Return to Sport Timeline
Conservative: 6-12 weeks to contact sport. Surgical: 6-9 months minimum. This timeline difference is CRITICAL when counseling athletes mid-season.
Biomechanical Impact
Throwing mechanics affected by AC instability - late cocking phase stress on AC joint. Overhead athletes may have persistent pain with horizontal adduction. Consider sport demands when deciding treatment.
Re-injury Risk
15-20% re-injury rate in contact sports after conservative treatment. Protective shoulder padding reduces risk. Surgical fixation does NOT eliminate re-injury risk (can fail).
AC Joint Injuries in Athletes - At a Glance
| Rockwood Type | Pathology | RTP Conservative | RTP Surgical | Athlete Decision |
|---|---|---|---|---|
| Type I | AC sprain, CC intact | 2-4 weeks | N/A (conservative only) | Sling, early ROM, excellent prognosis |
| Type II | AC torn, CC sprain | 4-6 weeks | N/A (conservative only) | Conservative treatment, good outcomes |
| Type III | CC torn, 25-100% displacement | 6-12 weeks | 6-9 months | CONTROVERSIAL - conservative first (80-90% success) |
| Type IV | Posterior displacement | N/A (surgical) | 6-9 months | Surgical - MUST get axillary view to diagnose |
| Type V | Over 100% displacement | N/A (surgical) | 9-12 months | Surgical - deltotrapezial repair critical |
| Type VI | Inferior displacement | N/A (surgical) | 9-12 months | Rare, surgical emergency, check for multi-trauma |
ATHLETE - RTP Decision Factors
Memory Hook:ATHLETE framework guides sport-specific RTP decision-making
RTP - Return to Play Criteria
Memory Hook:RTP criteria must ALL be met before return to contact/overhead sport
SPORT - Activity-Specific Concerns
Memory Hook:SPORT-specific factors influence conservative vs surgical decision
THROW - Throwing Athlete Considerations
Memory Hook:THROW considerations - throwing athletes MAY benefit from early surgery
Overview and Sports Epidemiology
AC joint injuries in athletes are among the most common shoulder injuries in contact and collision sports. The injury pattern, treatment considerations, and return to sport timeline differ significantly from non-athletic populations.
Sport-specific epidemiology:
| Sport | Injury Rate | Common Mechanism | Type Distribution |
|---|---|---|---|
| AFL/Rugby | 8-12 per 1000 athlete-exposures | Direct tackle to shoulder | Type II-III most common |
| Ice Hockey | 6-10 per 1000 exposures | Board collision | Type III-V higher rate |
| American Football | 3-5 per 1000 exposures | Tackling, blocking | Type II-III predominant |
| Cycling | 2-4 per 1000 exposures | Fall onto shoulder | Type III-IV patterns |
| Wrestling | 2-3 per 1000 exposures | Direct pressure | Type II-III typical |
Mechanism in athletes:
- Direct blow - fall onto point of shoulder with arm adducted (85% of cases)
- Axial loading - tackling with shoulder leading
- Indirect trauma - fall onto outstretched hand (rare, 15%)
- Chronic repetitive stress - throwing athletes (Type I-II sprains)
Athlete vs General Population
Athletes have higher rates of Type III-V injuries compared to general population (60% vs 40%) due to high-energy mechanisms. Re-injury rate is also higher in athletes returning to contact sports (15-20% vs under 10% general population).
Career impact considerations:
- Professional athletes: career implications, insurance, contract status
- College athletes: scholarship considerations, draft prospects
- Recreational athletes: quality of life, activity modification tolerance
- Timing: mid-season vs off-season affects surgical timing
Pathophysiology and Mechanisms
Functional anatomy in athletes:
The AC joint serves as the critical link between the axial skeleton (clavicle) and the appendicular skeleton (scapula). In athletes, this articulation is subjected to repetitive and high-magnitude forces.
AC Ligament Complex (horizontal stability):
| Structure | Function in Athletes | Sport-Specific Role |
|---|---|---|
| Superior AC ligament | 56% AP stability | Resists tackle/collision forces |
| Posterior AC ligament | 25% AP stability | Throwing follow-through stability |
| AC joint capsule | Proprioception | Neuromuscular control |
| Deltotrapezial fascia | Load sharing | Critical for overhead athletes |
CC Ligament Complex (vertical stability):
| Ligament | Position | Strength | Athletic Function |
|---|---|---|---|
| Conoid | Medial (45mm from AC) | Stronger | Primary vertical restraint |
| Trapezoid | Lateral (20mm from AC) | Secondary | Rotational control |
Biomechanics by sport:
Throwing Athletes (Cricket, Baseball, Javelin):
Phase-specific AC joint stress:
- Wind-up: Minimal AC stress
- Early cocking: Scapular positioning, moderate AC load
- Late cocking: PEAK AC STRESS - horizontal abduction stretches posterior AC ligament
- Acceleration: Rapid scapular protraction, AC shear forces
- Deceleration: High eccentric load on deltotrapezial complex
- Follow-through: Horizontal adduction compresses AC joint
Key point: Late cocking and deceleration place maximum stress on AC joint. Instability affects throwing mechanics and velocity.
Thrower's AC Joint
In throwing athletes, AC instability causes scapular dyskinesis leading to altered glenohumeral mechanics. This can reduce throwing velocity by 10-15% and increase risk of secondary rotator cuff or labral pathology.
Classification Systems
Athlete-specific classification considerations:
Type I - AC Ligament Sprain
Pathology:
- AC ligaments sprained, intact
- CC ligaments intact
- Deltotrapezial fascia intact
Athletic presentation:
- Localized AC joint tenderness
- Pain with cross-body adduction
- Full ROM, minimal weakness
- Negative piano key sign
RTP Timeline:
- Non-contact sports: 1-2 weeks
- Contact sports: 2-4 weeks
- Protective padding for first 4-6 weeks contact
Type II - AC Ligament Tear
Pathology:
- AC ligaments torn
- CC ligaments sprained but intact
- Slight vertical instability
Athletic presentation:
- Visible slight step-off
- Positive piano key sign
- Pain with overhead activities
- Horizontal instability on examination
RTP Timeline:
- Non-contact: 3-4 weeks
- Contact: 4-6 weeks
- Throwing: 4-8 weeks (symptom-based)
Both Type I and II are treated conservatively in athletes with excellent outcomes.
Clinical Assessment in Athletes
Sport-specific history:
Key questions:
- Sport and position played
- Level (professional, college, recreational)
- Hand dominance (critical in throwing sports)
- Time in season (pre-season, mid-season, playoffs, off-season)
- Mechanism (direct blow, fall, repetitive)
- Previous AC joint injuries (increased re-injury risk)
- Performance impact (pain with specific movements)
- Career implications (contract year, scholarship, draft)
Physical examination - Athlete-focused:
Athletic Performance Testing
| Test | Technique | Positive Finding | Athletic Significance |
|---|---|---|---|
| Cross-body adduction | Arm across body to opposite shoulder | AC joint pain | Predicts pain with tackling, blocking |
| O'Brien test | 90° flexion, 10° adduction, IR, resist downward | AC pain relieved with supination | Overhead/throwing mechanics affected |
| Piano key sign | Depress lateral clavicle, observe recoil | Clavicle depresses and springs back | CC ligament integrity - Type III+ |
| Horizontal stability | Translate clavicle AP with acromion fixed | Increased translation vs contralateral | AC ligament compromise - instability |
| Throwing simulation | Simulated throwing motion (late cocking) | AC pain during late cocking phase | Throwing athletes - biomechanics affected |
| Push-up test | Full push-up position with scapular protraction | AC pain or weakness | Contact athletes - blocking/tackling |
Sport-Specific Provocative Tests
Throwing athletes: Simulate late cocking position (horizontal abduction, external rotation) - reproduces AC stress. Contact athletes: Push-up test assesses scapular stability and deltotrapezial function. Overhead athletes: Cross-body adduction with resistance predicts pain during sport activities.
Functional assessment:
- Active ROM vs contralateral
- Strength testing (all shoulder movements)
- Scapular dyskinesis evaluation
- Sport-specific movement patterns
- Pain during athletic simulation
Investigations in Athletes
Standard imaging protocol:
1. AP and Zanca views:
- Zanca: 10-15° cephalic tilt
- Bilateral comparison (CC distance)
- Measure AC joint width
- Calculate displacement percentage
2. Axillary lateral view (MANDATORY):
- ONLY view to diagnose Type IV posterior displacement
- Type IV looks identical to Type III on AP view
- Must obtain in all AC joint injuries
Stress views (controversial in athletes):
- Weighted views with 5-10kg weights
- May help differentiate Type II from III
- Most centers no longer use routinely
- Pain limits utility in acute setting
- Decision rarely changed by stress views
Advanced imaging considerations:
MRI indications in athletes:
- Chronic AC joint pain (distal clavicle osteolysis)
- Suspected rotator cuff or labral pathology
- Pre-operative planning for chronic reconstruction
- Failed conservative treatment (assess for occult pathology)
Distal Clavicle Osteolysis
Weightlifter's shoulder - chronic repetitive stress causes distal clavicle osteolysis. Seen on MRI as bone marrow edema and clavicle resorption. Different from acute AC separation. Treatment: activity modification, NSAIDs, consider distal clavicle excision if persistent.
CT scan indications:
- Suspected fracture (clavicle, acromion, coracoid)
- Pre-operative planning for complex reconstruction
- Failed surgery (assess hardware, bone quality)
Ultrasound (emerging):
- Dynamic assessment of AC stability
- CC distance measurement
- Operator-dependent
- Not standard of care currently
Management Algorithm
Conservative Management - Type I-III Athletes
Goals: Pain control, protect healing tissues
- Ice 20 minutes every 2-3 hours
- NSAIDs (ibuprofen 400mg TDS or naproxen 500mg BD)
- Sling for comfort (wean by day 3-5)
- Avoid provocative movements (cross-body, overhead)
- Pendulum exercises starting day 2-3
- Pain-free gentle ROM
Return to training: Light cardio only if tolerated, no upper body
Goals: Restore ROM, begin strengthening
- Progress to full active ROM
- Scapular stabilization exercises
- Rotator cuff isometrics
- Light resistance band exercises
- Avoid heavy loading, cross-body movements
Return to training: Upper body ergometer, light weights (under 5kg)
RTP decision (Type I-II): If pain-free ROM and strength over 80%, progress to Phase 3 sport-specific
Goals: Restore strength, begin sport-specific training
- Progressive resistance training
- Deltotrapezial strengthening (shrugs, rows)
- Sport-specific movement patterns
- Proprioceptive training
- Bench press, push-ups (if pain-free)
Testing: Isokinetic strength over 90% contralateral for all movements
RTP decision (Type II-III): Progress to Phase 4 if strength goals met
Goals: Safe return to full competition
- Full contact practice with protective padding
- Sport-specific drills at game intensity
- Psychological readiness assessment
- Maintenance strengthening program
RTP criteria must ALL be met:
- Full pain-free ROM
- Strength over 90% contralateral (all movements)
- Sport-specific testing passed
- Athlete confidence restored
Protective equipment: AC joint padding for contact sports for 3-6 months
Conservative Success in Athletes
80-90% of athletes with Type III AC injuries return to sport successfully with conservative treatment. This includes contact and throwing athletes. Surgery should be reserved for the 10-20% who fail conservative treatment at 3-6 months.
Surgical Techniques for Athletes
Clavicle Hook Plate Fixation
Athlete-specific considerations:
Indications:
- Acute injury (under 3 weeks)
- Type III-V where rapid rigid fixation desired
- Off-season timing (allows removal at 3-4 months before next season)
Technique:
- Beach chair position, 30-45° upright
- Superior incision along Langer lines
- Identify and preserve lateral cutaneous nerve branches
- Reduce AC joint with manual pressure
- Hook placed 10-15mm medial to lateral clavicle edge
- Hook length: 15-18mm (avoid over-stuffing subacromial space)
- 3-4 cortical screws in clavicle
- Robust deltotrapezial fascia repair (critical for athletes)
Athlete-specific pearls:
- Deltotrapezial repair is CRITICAL - provides load sharing, allows earlier RTP
- Use non-absorbable suture (FiberWire, Ethibond) for fascia repair
- Rigid fixation allows earlier ROM compared to CC reconstruction
- Plan removal at 3-4 months (second surgery)
Complications in athletes:
- Subacromial impingement if hook too long or medial (50% if not removed)
- Acromion fracture/erosion (5-10%)
- Loss of reduction after removal (10-15%)
- MUST remove at 3-4 months - non-negotiable
Hook Plate Removal Timeline
Athletes MUST have hook plate removed at 3-4 months. Plan this during off-season if possible. After removal, allow 4-6 weeks before contact sport return. Some loss of reduction after removal is normal but usually asymptomatic.
Complications in Athletes
Athlete-Specific Complications
| Complication | Incidence | Impact on RTP | Prevention/Management |
|---|---|---|---|
| Re-injury (contact sports) | 15-20% conservative | Repeat time loss, may require surgery | Protective padding, strengthening, technique modification |
| Persistent pain | 10-20% both treatments | Limits performance, may end career | Adequate rehab, consider delayed surgery if conservative fails |
| Loss of strength | 5-10% (usually mild) | Reduces power in throws, tackles | Intensive strengthening, scapular stabilization |
| Scapular dyskinesis | 20-30% chronic instability | Secondary rotator cuff/labral issues | Scapular-focused rehab, periscapular strengthening |
| Surgical site infection | 1-2% surgical cases | Delays RTP 3-6 months, may require hardware removal | Sterile technique, perioperative antibiotics |
| Hardware failure | 5-15% depending on technique | Requires revision surgery, extends RTP | Appropriate technique, adequate fixation, protect healing |
| Coracoid/clavicle fracture | 2-5% CC reconstruction | Requires extended immobilization, delayed RTP | Avoid excessive tunnel size, adequate bone stock |
Career-ending complications:
While rare, certain complications may end athletic careers:
- Chronic pain syndrome - failed conservative and surgical treatment
- Recurrent instability - multiple surgical failures
- Neurovascular injury - brachial plexus injury during surgery (very rare)
- Chronic shoulder dysfunction - secondary rotator cuff or labral pathology
Cosmetic Deformity
Cosmetic deformity (visible bump) occurs in 80% of conservative Type III and 20% of surgical cases. This does NOT correlate with athletic performance or career longevity. Multiple studies show elite athletes perform at same level with cosmetic deformity. Counsel athletes appropriately.
Prevention of complications:
- Proper surgical technique
- Adequate rehabilitation compliance
- Protected return to sport
- Protective equipment for contact sports
- Monitoring for secondary pathology
Postoperative Care and Return to Play
Surgical rehabilitation protocol:
Goals: Protect repair, prevent stiffness
Weeks 0-2:
- Sling full time except exercises
- Pendulum exercises only
- Elbow/wrist/hand ROM
- No active shoulder motion
- Ice, wound care
Weeks 2-6:
- Sling when walking/sleeping
- Passive ROM to 90° elevation, neutral rotation
- Active-assisted ROM begins week 4
- Scapular retraction exercises (pain-free)
- No lifting, no resisted motion
Criteria to progress: Full passive ROM, pain under 3/10, wound healed
Goals: Full active ROM, begin strengthening
- Wean sling by week 6-8
- Progress to full active ROM
- Light resistance exercises (1-2kg)
- Scapular stabilization focus
- Rotator cuff strengthening
- Avoid heavy lifting, contact
Testing at 12 weeks:
- ROM: Should match contralateral
- Strength: 50-60% contralateral
- Pain: Under 2/10 with activities
Criteria to progress: Full pain-free active ROM, strength over 50%
Goals: Restore strength, begin sport-specific training
- Progressive resistance training
- Bench press, overhead press (light initially)
- Push-ups, pull-ups
- Plyometric exercises (late phase)
- Sport-specific movement patterns
- Proprioceptive training
Testing at 16 weeks:
- Strength: 80-90% contralateral
- Pain: Minimal (under 1/10)
- Functional testing passed
Criteria to progress: Strength over 85%, pain-free sport simulation
Goals: Safe return to full competition
Non-contact sports: 4-5 months Contact sports: 6-9 months Throwing sports: 6-12 months (gradual throwing progression)
RTP criteria (ALL must be met):
- Full pain-free ROM
- Strength over 90% contralateral (all movements)
- Isokinetic testing passed
- Sport-specific drills at game intensity
- Psychological readiness
- Clearance from surgeon and athletic trainer
Protective equipment: AC joint padding for contact sports 6-12 months
Sport-specific RTP guidelines:
AFL, Rugby, Ice Hockey, American Football:
Conservative treatment RTP:
- Type I: 2-4 weeks
- Type II: 4-6 weeks
- Type III: 6-12 weeks
Surgical treatment RTP:
- Hook plate: 6-9 months
- CC reconstruction: 6-9 months
- After hook plate removal: additional 4-6 weeks protected
Criteria:
- Contact practice without pain
- Tackling drills (for applicable positions)
- Strength over 95% (contact demands high)
- Protective AC joint padding
Padding recommendations:
- AC joint-specific pad (donut design)
- Worn for 3-6 months after RTP
- May reduce re-injury risk by 30-40%
Position-Specific RTP
Collision positions (linebacker, prop forward, defenseman) may need longer RTP timeline and more extensive strengthening compared to skill positions (quarterback, backs, forwards). Assess demands individually.
Outcomes and Return to Performance
Conservative treatment outcomes:
| Injury Type | RTP Rate | Time to RTP | Same Level Performance | Notes |
|---|---|---|---|---|
| Type I | 95-100% | 2-4 weeks | 95% | Excellent prognosis |
| Type II | 90-95% | 4-6 weeks | 90% | May have minor cosmetic deformity |
| Type III | 80-90% | 6-12 weeks | 85% | Cosmetic deformity common but functional |
Surgical outcomes:
| Technique | Success Rate | RTP Contact Sport | Same Level Performance | Complications |
|---|---|---|---|---|
| Hook plate | 80-85% | 6-9 months | 80-85% | Removal required, impingement risk |
| Anatomic CC | 85-90% | 6-9 months | 85-90% | Lower failure vs Weaver-Dunn |
| TightRope | 80-85% (early data) | 4-6 months | 85% | Limited long-term data |
Performance After AC Injury
Elite athlete performance data shows NO significant difference in career longevity, statistics, or performance metrics between athletes with conservative vs surgical treatment for Type III injuries. Cosmetic deformity does NOT predict performance.
Factors affecting athlete outcomes:
Positive prognostic factors:
- Young age (under 25 years)
- Type I-II injury
- Compliance with rehabilitation
- Access to specialized sports medicine care
- Off-season injury timing
- Non-throwing sport
Negative prognostic factors:
- Type V injury (severe soft tissue disruption)
- Multiple re-injuries
- Associated pathology (rotator cuff, labrum)
- Poor rehabilitation compliance
- In-season injury with rushed return
- Throwing athlete with Type III
Sport-specific outcome data:
NFL players (American football):
- 95% RTP after Type I-II
- 85% RTP after Type III (conservative)
- Same performance statistics pre vs post-injury
- Average time loss: 2-4 weeks Type I-II, 6-8 weeks Type III
Professional rugby:
- 90% RTP after conservative Type III
- Forwards (higher re-injury): 20% re-injury rate
- Backs (lower re-injury): 10% re-injury rate
- Protective padding reduces re-injury by 30-40%
MLB pitchers (baseball):
- 80% RTP after Type III conservative
- Velocity loss under 5% (not significant)
- Surgery delays RTP but similar long-term outcomes
- Biomechanics normalize by 6-12 months
Evidence Base
- 83 patients with acute Type III AC separations randomized to operative (modified Weaver-Dunn) vs non-operative. No significant difference in DASH scores, Constant scores, or patient satisfaction at 2 years. Operative group had higher complication rate.
- Pooled analysis of 12 studies (461 patients) comparing operative vs non-operative for Type III. No significant difference in functional outcomes, return to work, or satisfaction. Operative group had 29% complication rate vs 10% conservative.
- Systematic review comparing anatomic vs non-anatomic CC reconstruction. Anatomic reconstruction (both conoid and trapezoid) demonstrated superior outcomes: 12% failure rate vs 27% for Weaver-Dunn. Better restoration of horizontal stability.
- 168 NFL players with AC joint injuries (Type I-III) followed for career outcomes. 94% RTP. No difference in games played, statistics, or career length between operative and non-operative Type III. Cosmetic deformity did not correlate with performance.
- 62 athletes randomized to hook plate vs TightRope for Type III-V injuries. TightRope group had faster RTP (4.5 vs 7.2 months), lower complication rate (8% vs 24%), no hardware removal needed. Similar functional outcomes at 2 years.
Exam Viva Scenarios
Practice these scenarios to excel in your viva examination
Scenario 1: Elite Throwing Athlete Type III
"A 22-year-old professional cricket fast bowler sustained a Type III AC joint separation to his bowling arm 2 weeks ago during a match. X-rays show 80% superior displacement with CC distance 18mm (contralateral 12mm). He is currently mid-season with 6 weeks remaining. His team is in playoff contention and wants him to return ASAP. He asks about surgery. How would you manage this case?"
Scenario 2: Contact Athlete Recurrent Instability
"A 19-year-old university rugby prop forward presents with recurrent right AC joint instability. He had a Type III AC separation 9 months ago treated conservatively. He returned to rugby at 10 weeks wearing protective padding but has had 3 episodes of the shoulder 'giving way' during scrums. X-rays show persistent 60% superior displacement. He is currently off-season with 4 months until pre-season training. What is your management?"
Scenario 3: Acute Type IV Missed Diagnosis
"A 24-year-old professional cyclist presents to you 3 weeks after a high-speed crash. He was diagnosed with a Type III AC separation at another hospital and treated with sling for 2 weeks. He has been trying to return to training but has severe pain and the shoulder 'doesn't feel right.' On examination the lateral clavicle is prominent posteriorly and difficult to palpate anteriorly. You review the images - there is an AP shoulder X-ray showing superior clavicle displacement but no axillary view was done. What is your concern and management?"
MCQ Practice Points
Type III Athlete Management
Q: A 20-year-old college football linebacker sustains an acute Type III AC separation mid-season. What is the most appropriate initial management?
A: Conservative treatment with sling, ice, analgesia, and early ROM. Level I evidence (CRAC trial) shows no difference in outcomes between operative and non-operative Type III at 2 years. 80-90% of athletes RTP successfully with conservative treatment. Surgery reserved for failed conservative at 3-6 months or specific indications (throwing athletes, off-season timing).
RTP Timeline Question
Q: An athlete with Type III AC separation asks about return to contact sport timeline. What is the expected RTP with conservative vs surgical treatment?
A: Conservative: 6-12 weeks. Surgical: 6-9 months. This timeline difference is CRITICAL when counseling athletes, especially mid-season. Surgical treatment commits to season-ending recovery, while conservative allows potential return same season.
Imaging Question
Q: What imaging view is ESSENTIAL to differentiate Type III from Type IV AC joint separation?
A: Axillary lateral view. Type IV (posterior displacement) looks identical to Type III on AP view. Axillary view shows clavicle displaced posterior to acromion. Failing to obtain axillary view leads to missed Type IV diagnosis and failed conservative treatment.
Throwing Athlete Biomechanics
Q: Why might throwing athletes have different outcomes with Type III AC separations compared to contact athletes?
A: Throwing biomechanics place high stress on AC joint during late cocking (horizontal abduction) and deceleration phases. AC instability can cause scapular dyskinesis, reduce throwing velocity by 10-15%, and increase risk of secondary rotator cuff or labral pathology. Some throwing athletes may benefit from early surgery, though evidence is mixed.
Surgical Technique Question
Q: Why is hook plate NOT suitable for chronic AC joint injuries (over 6 weeks)?
A: Hook plate provides temporary rigid fixation that requires removal at 3-4 months. It works in acute injuries where soft tissue healing is occurring. In chronic injuries, soft tissues have already healed in malaligned position and anatomic CC ligament reconstruction is needed to restore stability. Hook plate would fail in chronic setting.
Evidence-Based Question
Q: What Level I evidence exists regarding Type III AC separation management in athletes?
A: The CRAC trial (2015, JBJS) randomized 83 patients with Type III to operative vs non-operative. No significant difference in DASH scores, Constant scores, or satisfaction at 2 years. Operative group had higher complication rate (29% vs 10%). Smith et al meta-analysis (2011, AJSM) pooled 12 studies (461 patients) and confirmed no functional difference. This is the strongest evidence supporting conservative first-line treatment.
Australian Context and Local Considerations
Australian sports epidemiology:
AFL (Australian Football League):
- AC joint injuries: 8-12 per 1000 player-hours
- Peak incidence in tackles and marking contests
- Type II-III most common (60% of AC injuries)
- Season timing: March-September affects surgical decisions
- Most clubs have sports medicine physicians managing conservatively
Rugby (Union and League):
- High contact sport with elevated AC injury rates
- Forwards (props, locks) highest risk positions
- Type III-V more common than other field sports
- Professional/NRL level: access to rapid imaging and specialist care
- Protective padding mandatory on return to play
Cricket:
- Fast bowlers: repetitive stress, acute injuries from diving
- AC joint pain common in bowling shoulder
- Season: October-March (summer) - timing considerations
- Elite level (State, International): specialist sports medicine support
Cycling:
- Road cycling popular, high AC injury rates from falls
- Mountain biking: higher-energy mechanisms, Type III-V
- Tour Down Under and other events: acute on-site management
- Return to competitive cycling: 4-8 weeks conservative, 4-6 months surgical
Management in Australian healthcare system:
Public vs Private:
- Public hospitals: may have delays for elective AC surgery (4-8 week wait)
- Private insurance: faster access to surgery if indicated
- Sports medicine clinics: rapid assessment and conservative management
- Elite athletes: often private system with team doctors
WorkCover considerations:
- Occupational AC injuries (construction, manual labor)
- WorkCover may cover conservative or surgical treatment
- Return to work timelines: clerical 2-4 weeks, manual 8-12 weeks, heavy labor 12-16 weeks
- Permanent impairment ratings if chronic symptoms
Return to sport protocols:
Australian sports medicine organizations emphasize:
- Medical clearance before RTP contact sports
- Graduated return protocol (training → non-contact → contact → competition)
- Protective equipment (AC padding) for 3-6 months
- Shared decision-making with athlete, team, medical staff
- Insurance and liability considerations for professional athletes
Cultural factors:
- AFL and rugby have strong "play through pain" culture
- Medical staff must balance athlete pressure with safety
- Professional teams increasingly adopting evidence-based conservative approaches
- Cosmetic deformity generally well-accepted in male contact athletes
AC JOINT INJURIES IN ATHLETES
High-Yield Exam Summary
TYPE III CONTROVERSY IN ATHLETES
- •CRAC trial (Level I): NO difference operative vs conservative at 2 years
- •80-90% of athletes RTP successfully with conservative treatment
- •Conservative RTP: 6-12 weeks vs Surgical RTP: 6-9 months
- •Default to CONSERVATIVE even in elite athletes
- •Consider surgery: throwing athletes, failed conservative 3-6 months, off-season
- •Cosmetic deformity does NOT predict athletic performance
RETURN TO SPORT CRITERIA
- •Full pain-free ROM (equal to contralateral)
- •Strength over 90% contralateral (all movements, isokinetic testing)
- •Sport-specific testing passed (throwing velocity, tackling drills, etc)
- •Psychological readiness restored
- •Protective AC joint padding for contact sports 3-6 months
SPORT-SPECIFIC TIMELINES
- •Contact sports (AFL, rugby): 6-12 weeks conservative, 6-9 months surgical
- •Throwing sports (cricket, baseball): 8-16 weeks conservative, 6-12 months surgical
- •Overhead sports (swimming, tennis): 6-10 weeks conservative, 4-6 months surgical
- •Cycling: 4-8 weeks conservative, 4-6 months surgical
- •Re-injury rate contact sports: 15-20% (protective padding reduces by 30-40%)
IMAGING ESSENTIALS
- •MANDATORY: AP + Zanca + AXILLARY view (all AC injuries)
- •Axillary view ONLY way to diagnose Type IV (posterior displacement)
- •Type IV looks IDENTICAL to Type III on AP view alone
- •Stress views controversial, rarely change management
- •MRI for chronic pain (distal clavicle osteolysis, cuff pathology)
SURGICAL DECISION-MAKING
- •Absolute indications: Type IV, V, VI
- •Relative indications athletes: throwing athletes, failed conservative 3-6 months
- •Hook plate: acute only (under 3 weeks), MUST remove 3-4 months
- •Anatomic CC reconstruction: chronic injuries, throwing athletes, permanent solution
- •TightRope: minimally invasive, no removal, faster RTP, emerging technique
- •CRITICAL: robust deltotrapezial fascia repair for all athletes
THROWING ATHLETE SPECIFICS
- •Late cocking phase: peak AC joint stress (horizontal abduction)
- •AC instability causes scapular dyskinesis, reduces velocity 10-15%
- •May benefit from early surgery (controversial, no Level I evidence)
- •Interval throwing program: 12 weeks gradual progression
- •Monitor velocity, mechanics, pain throughout progression
CRITICAL EXAM TRAPS
- •Don't reflexively operate on Type III athletes (80-90% conservative success)
- •Don't miss Type IV (no axillary view = missed diagnosis)
- •Don't use hook plate for chronic injuries (over 6 weeks)
- •Don't forget deltotrapezial repair (critical for athletes)
- •Don't rush return (re-injury risk 15-20% if premature)
- •Don't ignore cosmetic deformity counseling (expected, doesn't affect function)