Location Determines Treatment | Midshaft Most Common | Displacement Key Factor
ALLMAN CLASSIFICATION
Critical Must-Knows
- Displacement and shortening are key surgical indications for midshaft fractures
- COTS study showed improved union rates but no functional difference at 1 year
- Type II lateral clavicle fractures are unstable - CC ligaments torn
- Floating shoulder = scapula neck + clavicle - surgical stabilization often needed
- Plate position: superior vs anteroinferior - both acceptable, different complications
Clinical Pearls
- "Edinburgh study changed practice - 15% nonunion rate for displaced midshaft
- "Neer Type II lateral = CC ligament disruption = unstable = surgery
- "Shortening over 2cm correlates with poor functional outcomes
- "Medial clavicle fractures - CT for posterior displacement (vascular risk)
Clinical Imaging
Imaging Gallery
Critical Clavicle Fracture Exam Points
Displaced Midshaft
Shortening greater than 2cm and 100% displacement are key surgical indications. COTS/Edinburgh data showed improved union with ORIF but similar long-term function.
Lateral Classification
Neer Type II has CC ligament disruption = unstable = high nonunion rate. Type I (lateral to CC) and Type III (articular) are usually stable.
Medial Fractures
Posterior displacement is dangerous - CT essential. Risk to great vessels and trachea. Physis closes at 23-25 years - beware SC dislocation in young adults.
Floating Shoulder
Clavicle + scapula neck fracture = double disruption of superior shoulder suspensory complex. Often requires clavicle fixation for stability.
Quick Decision Guide
| Fracture Pattern | Key Finding | Stability | Treatment |
|---|---|---|---|
| Midshaft - minimal displacement | Less than 100% displacement, shortening less than 2cm | Good prognosis | Sling, early ROM, union expected |
| Midshaft - significantly displaced | Greater than 2cm shortening, 100% displacement | Higher nonunion risk | Discuss surgery - similar function at 1yr |
| Lateral Type II | CC ligament disruption, unstable fragment | Unstable | Surgical fixation - hook plate or sutures |
| Medial with posterior displacement | CT shows posterior fragment near vessels | Dangerous | CT angiogram, likely open reduction |
| Floating shoulder | Clavicle + scapula neck fracture | Complex instability | Clavicle ORIF stabilizes construct |
ORIF BCOTS - Midshaft ORIF Benefits
| C | Cosmesis Better cosmetic appearance with ORIF |
| O | Osseous union Higher union rates with surgery |
| T | Time to union Faster healing with fixation |
| S | Similar function Similar DASH scores at 1 year |
| C | Cosmesis Better cosmetic appearance with ORIF | T | Time to union Faster healing with fixation |
| O | Osseous union Higher union rates with surgery | S | Similar function Similar DASH scores at 1 year |
Hook:COTS study showed ORIF gives better union but COmparable long-Term Score
PLATE - SPLATE - Surgical Indications
| P | Polytrauma Early mobilization needed |
| L | Length (shortening greater than 2cm) Key prognostic factor |
| A | Athlete/Laborer Early return to activity desired |
| T | Threatened skin Tenting, impending open fracture |
| E | Extreme displacement 100% displaced or comminuted |
| P | Polytrauma Early mobilization needed | T | Threatened skin Tenting, impending open fracture |
| L | Length (shortening greater than 2cm) Key prognostic factor | E | Extreme displacement 100% displaced or comminuted |
| A | Athlete/Laborer Early return to activity desired |
Hook:PLATE the clavicle when these indications are met
NEER - LNEER - Lateral Clavicle Types
| I | Intact CC ligaments Type I: Fracture lateral to CC = stable |
| II | Interrupted CC ligaments Type II: CC disruption = unstable = surgery |
| III | Into the joint Type III: Articular surface = stable, may cause OA |
| I | Intact CC ligaments Type I: Fracture lateral to CC = stable |
| II | Interrupted CC ligaments Type II: CC disruption = unstable = surgery |
| III | Into the joint Type III: Articular surface = stable, may cause OA |
Hook:Type II = II ligaments torn (trapezoid + conoid) = Instability
2-2-2 R2-2-2 Rule for Midshaft Surgery
| 2 | 2cm shortening Greater than 2cm indicates surgery |
| 2 | 2 weeks to decide Early ORIF within 2 weeks best outcomes |
| 2 | 2x complication risk Delayed fixation doubles complication rate |
| 2 | 2cm shortening Greater than 2cm indicates surgery |
| 2 | 2 weeks to decide Early ORIF within 2 weeks best outcomes |
| 2 | 2x complication risk Delayed fixation doubles complication rate |
Hook:If shortening exceeds 2cm, decide within 2 weeks or double your trouble
Overview and Epidemiology
Clavicle fractures are among the most common orthopaedic injuries, representing approximately 4-5% of all fractures. The clavicle is a unique bone that serves as the only bony connection between the upper limb and the axial skeleton.
Mechanism of injury:
- Direct blow - fall onto the point of the shoulder (most common)
- Indirect - FOOSH (fall on outstretched hand) transmits force
- High-energy - motor vehicle accidents, sports injuries
Bimodal distribution:
- Young males (high-energy sports/trauma)
- Elderly (low-energy falls with osteoporosis)
S-Shaped Anatomy
The clavicle is S-shaped with the medial curve convex anteriorly and the lateral curve convex posteriorly. The junction of these curves (middle third) is the thinnest point and lacks ligamentous attachments, explaining the high fracture rate here.
Anatomy and Biomechanics
Bony anatomy:
- First bone to ossify (5th week in utero)
- Last bone to fuse (medial physis closes 23-25 years)
- S-shaped: medial 2/3 convex anteriorly, lateral 1/3 convex posteriorly
- Middle third is the thinnest with no ligamentous attachments
Muscular attachments:
- SCM (sternocleidomastoid) - inserts medial third, elevates medial fragment
- Trapezius - inserts lateral third, may elevate lateral fragment
- Deltoid - originates from lateral third
- Pectoralis major - originates from medial third, depresses fragment
Critical relationships:
Neurovascular Structures
Subclavian vessels and brachial plexus pass directly posterior to the middle third. The subclavius muscle and clavipectoral fascia provide protection. Acute vascular injury rare but posterior medial displacement is dangerous.
Ligamentous structures:
- Coracoclavicular (CC) ligaments - trapezoid (lateral) and conoid (medial) - key stabilizers
- Acromioclavicular ligament - horizontal stability of AC joint
- Sternoclavicular ligaments - anchor medial clavicle
Deforming Forces
In midshaft fractures: medial fragment elevates (SCM pull) and retracts posteriorly (trapezius). Lateral fragment depresses (weight of arm) and medializes (pectoralis/deltoid). This creates the classic "step-off" deformity.
Vascular supply:
- Periosteal vessels (branches of suprascapular, thoracoacromial, internal thoracic)
- Nutrient artery enters near middle third
- Comminuted fractures disrupt blood supply - higher nonunion risk
Classification Systems
Allman Classification (by location - most commonly used)
| Group | Location | Frequency | Key Features |
|---|---|---|---|
| I | Middle third | 80% | Between CC ligaments and costoclavicular ligament |
| II | Lateral third | 15% | Lateral to CC ligaments |
| III | Medial third | 5% | Medial to costoclavicular ligament |
Group I Significance
Middle third fractures occur at the junction of the two curves where the bone is thinnest and has no ligamentous attachments. This explains both the high incidence and propensity for displacement.
Clinical Presentation and Assessment
History:
- Mechanism (fall onto shoulder, direct blow, FOOSH)
- High vs low energy
- Hand dominance
- Occupation and activity level
- Associated injuries (floating shoulder, chest trauma)
Physical examination:
Physical Examination Findings
| Finding | Significance | Action Required |
|---|---|---|
| Visible/palpable deformity | Displacement present | Assess degree of shortening |
| Skin tenting | Impending open fracture | Urgent - relative surgical indication |
| Neurovascular deficit | Brachial plexus/vascular injury | Urgent surgical exploration |
| Dyspnea/chest pain | Pneumothorax | Chest X-ray, tube thoracostomy if needed |
| Ipsilateral shoulder pain | Floating shoulder | Full shoulder girdle imaging |
Neurovascular examination:
- Brachial plexus assessment (especially lateral cord - musculocutaneous, median)
- Radial, ulnar, median nerve function
- Distal pulses, capillary refill
- Signs of venous congestion
Associated Injuries
Look for floating shoulder (clavicle + scapula neck), AC joint injury, pneumothorax (especially with first rib fracture), and brachial plexus injury (particularly in high-energy trauma).
Signs of significant displacement:
- Obvious step-off deformity
- Shortening (compare to contralateral side)
- Tenting of skin
- Pain with any shoulder movement
Differential diagnosis:
Differential Diagnosis of the Painful, Deformed Shoulder Girdle
| Condition | Distinguishing Features | Confirming Investigation |
|---|---|---|
| Acromioclavicular joint dislocation | Tenderness over AC joint, step at the joint not the shaft, positive cross-body adduction | AP and Zanca views, weighted views if needed |
| Sternoclavicular dislocation | Medial swelling, dysphagia or venous congestion if posterior | CT with angiography for posterior displacement |
| Proximal humerus fracture | Pain and bruising over proximal humerus, restricted glenohumeral movement | AP, scapular-Y and axillary radiographs |
| Scapula or floating shoulder | High-energy mechanism, scapular tenderness, double disruption | Full shoulder girdle imaging, CT |
| Pathological fracture | Low-energy mechanism, antecedent pain, history of malignancy | Radiographs for lytic lesion, staging and biopsy as indicated |
| Medial physeal fracture-separation (young adult) | Age under 25 years, mimics SC dislocation as physis still open | CT to differentiate from true SC dislocation |
Investigations
Radiographic Examples
Standard imaging:
AP Clavicle X-ray:
- 15-degree cephalic tilt provides best view
- Assess displacement, shortening, comminution
- Measure shortening by comparing to contralateral side
45-degree cephalic tilt view:
- Separates clavicle from overlying ribs/scapula
- Better assessment of displacement and comminution
Shortening Measurement
Measure clavicle length on AP X-ray from sternal to acromial end. Compare to contralateral side. More than 2cm shortening is a key surgical threshold. CT provides more accurate measurement if needed.
When to order CT:
CT Indications in Clavicle Fractures
| Indication | Rationale |
|---|---|
| Medial clavicle fracture | Assess posterior displacement, vascular proximity |
| Complex lateral fracture | Define CC ligament attachment, fracture pattern |
| Floating shoulder | Define scapula fracture pattern for surgical planning |
| Comminuted midshaft (surgical planning) | Accurate shortening measurement, fragment assessment |
CT angiogram:
- Indicated for medial fractures with posterior displacement
- Any concern for vascular injury (expanding hematoma, pulse deficit)
Chest X-ray:
- Rule out pneumothorax
- Especially with first rib fracture or high-energy mechanism
Management
Conservative management:
Most clavicle fractures can be treated conservatively with excellent outcomes.
- Simple sling for comfort (arm sling preferred over figure-of-8)
- Ice, analgesia
- Gentle pendulum exercises when pain allows
- Wean from sling as pain allows
- Active ROM exercises below 90 degrees
- Avoid heavy lifting
- Progressive strengthening once clinical union
- Return to non-contact sports typically 8-12 weeks
- Contact sports delayed until radiographic union (12-16 weeks)
Figure-of-8 vs Sling
Simple arm sling is preferred over figure-of-8 brace. A Cochrane review showed no difference in outcomes, and figure-of-8 braces cause axillary discomfort and skin problems. Only advantage is cosmetic improvement of posture.
Surgical Technique
Plate and screws - gold standard for midshaft fractures
Superior plating:
- Easier exposure
- Better cosmesis
- Plate prominence, hardware irritation common
Anteroinferior plating:
- Less prominence
- Subcutaneous suture line
- More difficult exposure
- Protected from direct trauma
Plate selection:
- 3.5mm reconstruction plate (can be contoured)
- Precontoured clavicle plates (anatomic)
- Locking plates for osteoporotic bone or comminution
Plate Position
Superior plating is most common but has higher hardware prominence. Anteroinferior plating is biomechanically similar with less prominence but technically more demanding. Both acceptable - surgeon preference.
Complications
Complications by Treatment Type
| Complication | Conservative Rate | Surgical Rate | Management |
|---|---|---|---|
| Nonunion | 5-15% | 1-2% | Bone grafting, revision ORIF |
| Malunion | Variable | Rare | Accept most; osteotomy if symptomatic |
| Hardware irritation | N/A | 20-40% | Hardware removal at union |
| Infection | N/A | 1-2% | Antibiotics, debridement if deep |
| Neurovascular injury | Rare | 0.5-1% | Intraop recognition, vascular repair |
| Refracture | Rare | 1-2% | After hardware removal; wait 12 weeks |
Nonunion:
Risk factors for nonunion:
- Displacement greater than 100%
- Shortening greater than 2cm
- Comminution
- Female sex
- Older age
- Smoking
- Refracture
Nonunion Management
Clavicle nonunion treatment: plate fixation + bone grafting (iliac crest or local autograft). Address biomechanical (length, alignment) and biological (vascularity, bone quality) factors.
Malunion:
- Shortening, angulation, and rotation
- Usually well tolerated
- Surgery only for symptomatic cases (shoulder dysfunction, cosmesis)
- Corrective osteotomy with plate fixation
Hardware-Related Complications
Plate prominence is the most common reason for hardware removal (20-40% of patients). Counsel patients preoperatively. Anteroinferior plating may reduce this but is technically more demanding.
Postoperative Care and Rehabilitation
Post-ORIF protocol:
- Sling for comfort
- Gentle pendulum exercises
- No active elevation
- Wound care
- Wean sling
- Active assisted ROM
- Progress to active ROM as tolerated
- No lifting greater than 2-3kg
- Progressive strengthening
- Return to desk work usually possible
- No heavy lifting or contact sports
- Confirm radiographic union
- Return to full activities
- Contact sports typically 4-6 months
- Hardware removal if symptomatic (12+ months)
Key rehabilitation principles:
- Early pendulum exercises prevent stiffness
- Progressive loading only after clinical union
- Hardware removal is optional unless symptomatic
- Full sports clearance requires radiographic union
Return to Sport
Athletes can return to non-contact sports at 8-12 weeks with clinical union and adequate ROM. Contact sports require radiographic union, typically 4-6 months. Elite athletes may have earlier return with protective padding.
Outcomes and Prognosis
Prognosis by fracture type:
| Fracture Type | Conservative Union | ORIF Union | Notes |
|---|---|---|---|
| Undisplaced midshaft | 95%+ | 98-99% | Conservative treatment preferred |
| Displaced midshaft | 85% | 98% | ORIF faster union, similar function |
| Neer Type I lateral | 90%+ | 95%+ | Conservative preferred |
| Neer Type II lateral | 67-78% | 90-95% | ORIF strongly preferred |
| Medial clavicle | 90%+ | 95%+ | Conservative unless displaced posteriorly |
COTS Study Summary
Canadian Orthopaedic Trauma Society (COTS) 2007: RCT of 132 patients comparing plate fixation vs sling for completely displaced midshaft fractures. ORIF showed lower nonunion (2 of 62 vs 7 of 49), faster union (16.4 vs 28.4 weeks), and better Constant/DASH scores up to 1 year. The later network meta-analysis confirmed the functional advantage does not reach the minimal clinically important difference. Changed practice toward considering surgery for displaced fractures.
Factors affecting outcomes:
- Degree of shortening (more than 2cm worse outcomes)
- Smoking (delays union, increases complications)
- Age and bone quality
- Compliance with rehabilitation
- Patient expectations and activity demands
Evidence Base
- Multicentre RCT of 132 patients with completely displaced midshaft fractures. Plate fixation reduced nonunion (2 of 62 operative vs 7 of 49 nonoperative) and symptomatic malunion (0 vs 9), shortened time to union (16.4 vs 28.4 weeks), and improved Constant and DASH scores at all time points up to 1 year.
- Prospective observational cohort of 868 nonoperatively treated clavicle fractures. Overall nonunion at 24 weeks was 6.2% (diaphyseal 4.5%, lateral 11.5%, medial 8.3%). Independent predictors of diaphyseal nonunion were lack of cortical apposition (displacement), comminution, female sex and advancing age.
- Network meta-analysis of 22 RCTs (1965 patients). Union at 1 year was 88.9% nonoperative versus 96.7% operative (NNT approximately 10 to avoid one nonunion). Functional gains with surgery did not reach the minimal clinically important difference for DASH; nonunion after nonoperative care was slightly above 10%.
- Meta-analysis of 34 studies (1494 patients). Union, nonunion, malunion and functional scores were equivalent for superior and anteroinferior plating, but superior plating had significantly more symptomatic hardware (17% vs 8%) and more frequent implant removal (11% vs 5%).
- Cochrane review of 3 trials (354 participants). Figure-of-eight bandage showed no functional advantage over a simple arm sling and caused more pain and discomfort; low-intensity pulsed ultrasound did not accelerate union.
- Population-based study (Malmo, Sweden) of all shoulder girdle injuries in one year. Clavicle fractures were the commonest shoulder girdle injury in children (65 of 75) and frequent in adults (67 of 181), with adult injuries significantly more common in men and predominantly caused by traffic and sport.
Clinical Decision Scenarios
Use these scenarios to practise clinical reasoning and management decisions
Scenario 1: Displaced Midshaft Fracture
"A 25-year-old male cyclist presents after a fall onto his right shoulder. X-ray shows a displaced midshaft clavicle fracture with 2.5cm shortening and 100% displacement. He is a manual laborer. How would you manage this patient?"
Scenario 2: Lateral Third Fracture
"A 45-year-old woman presents with a lateral third clavicle fracture. X-rays show the fracture between the CC ligaments with significant displacement of the medial fragment. What is your assessment and management?"
Scenario 3: Medial Clavicle Injury
"An 18-year-old presents with a medial clavicle injury after a rugby tackle. There is swelling at the sternoclavicular area, the patient reports difficulty swallowing, and the arm is held adducted. X-rays are difficult to interpret. What are your concerns and management?"
MCQ Practice Points
Classification Question
Q: What percentage of clavicle fractures occur in the middle third? A: 80%. The middle third is the thinnest portion of the clavicle, at the junction of the two curves, and lacks ligamentous attachments - making it the most vulnerable to fracture.
Anatomy Question
Q: At what age does the medial clavicle physis close? A: 23-25 years. This is the last physis in the body to fuse. Injuries in young adults appearing as SC dislocations are often physeal fracture-separations.
Surgical Indication Question
Q: What shortening threshold is a key indication for ORIF of midshaft clavicle fractures? A: Greater than 2cm shortening. Along with 100% displacement, this is associated with higher nonunion rates and functional impairment.
Evidence Question
Q: What was the key finding of the COTS study regarding operative vs non-operative treatment of displaced midshaft clavicle fractures? A: ORIF resulted in fewer nonunions (2 of 62 operative vs 7 of 49 nonoperative) and faster union, with no clinically important difference in functional scores at 1 year (the network meta-analysis confirmed the functional gain is below the MCID).
Lateral Fracture Question
Q: Which Neer classification type of lateral clavicle fracture has the highest nonunion rate? A: Type II (22-33% nonunion). The CC ligament disruption leaves the medial fragment unstable and elevated by the trapezius.
Guidelines, Registries & Global Practice
Global epidemiology
| Measure | Value | Source |
|---|---|---|
| Proportion of all fractures | Approximately 2.6-5% | Population fracture series |
| Commonest shoulder girdle injury in children | 65 of 75 injuries | Nordqvist & Petersson 1995 |
| Adult sex predominance | Male (sport/traffic mechanism) | Nordqvist & Petersson 1995 |
| Site distribution | Midshaft approximately 80%, lateral approximately 15%, medial approximately 5% | Allman / Robinson cohorts |
| Overall conservative nonunion at 24 weeks | 6.2% (diaphyseal 4.5%, lateral 11.5%) | Robinson 2004 |
The bimodal pattern - young men injured in sport or road trauma and older patients sustaining fragility injuries from low falls - is consistent across high-income population studies and shapes both management and counselling.
Guideline and society positions, side by side
| Body | Position on displaced midshaft fractures | Evidence basis |
|---|---|---|
| AO Foundation / OTA | Nonoperative care is the default; fixation reserved for absolute indications (open, neurovascular, skin compromise) and selected displaced fractures after shared decision-making | RCT and meta-analysis evidence |
| AAOS (US) | No mandate for routine surgery; shared decision-making citing faster union and lower nonunion with surgery against hardware-related reoperation | Level I RCTs |
| BOA / UK practice | Predominantly nonoperative; surgery offered for high-risk displaced fractures and absolute indications, reflecting equivalence of long-term function | Cochrane and RCT data |
| EFORT / European consensus | Individualised - operative fixation for completely displaced, shortened or comminuted fractures in active patients | Network meta-analysis |
Across all major bodies the recommendations have converged: surgery reliably improves union (number needed to treat approximately 10) and early function but does not deliver a patient-perceptible long-term functional gain, so the decision is shared and indication-led rather than mandatory.
Registry and high-level evidence
- The COTS multicentre RCT established lower nonunion and malunion with plate fixation of completely displaced fractures, but with hardware removal as the leading reoperation.
- The Axelrod network meta-analysis of 22 RCTs quantified union at 88.9% (nonoperative) versus 96.7% (operative), with functional differences below the minimal clinically important difference.
- The Nourian meta-analysis found superior and anteroinferior plating equivalent for union and function, with anteroinferior placement reducing symptomatic hardware and removal.
Global practice variation
- In high-resource settings, displaced fractures in athletes and manual workers are increasingly offered early fixation to shorten time to union and return to work, despite equivalent long-term function.
- In limited-resource settings, nonoperative management predominates given the low absolute nonunion risk and the cost, implant and theatre demands of fixation; this is an evidence-consistent choice rather than a compromise.
- Lateral Neer type II fractures attract a more uniformly operative stance worldwide because of their substantially higher nonunion risk.
CLAVICLE FRACTURES
Clinical summary
CLASSIFICATION
- •Allman: I (80% middle), II (15% lateral), III (5% medial)
- •Neer lateral: I (stable), II (unstable - CC disrupted), III (articular)
- •Robinson: 2A (aligned), 2B (displaced) - key for prognosis
- •Edinburgh: expanded Robinson - includes comminution assessment
KEY NUMBERS
- •Greater than 2cm shortening = consider ORIF
- •15% nonunion rate for displaced midshaft (conservative)
- •22-33% nonunion for Neer Type II (lateral)
- •23-25 years = medial physis closure age
SURGICAL INDICATIONS
- •Open fracture, neurovascular compromise
- •Impending skin perforation (tenting)
- •Shortening greater than 2cm, 100% displacement
- •Neer Type II lateral fracture
- •Floating shoulder (relative)
- •Polytrauma needing early mobilization
COTS STUDY SUMMARY
- •ORIF reduces nonunion: 2 of 62 vs 7 of 49 (COTS 2007)
- •Faster union with surgery (16.4 vs 28.4 weeks)
- •Better early Constant/DASH scores with ORIF
- •Functional benefit below MCID - similar at 1 year (Axelrod NMA 2020)
SURGICAL OPTIONS
- •Superior plate: easier exposure, more prominence
- •Anteroinferior plate: less prominence, harder
- •IM nail: smaller incision, migration risk
- •Hook plate (lateral): needs removal at 3-6 months
TRAPS AND PEARLS
- •Medial injury in less than 25yo = physeal, not SC dislocation
- •Posterior medial displacement = CT angio, vascular risk
- •Figure-of-8 no better than sling - sling preferred
- •Floating shoulder = consider clavicle fixation
- •Hook plate = plan for routine removal