Scaphoid Fracture

Epidemiology

Anatomy & Blood Supply - The Key to Understanding Complications

• A fracture across the waist cuts off the blood supply to the proximal fragment
• Approximately 10% of individuals have a sole blood supply from the radial artery, making AVN prediction impossible
• The more proximal the fracture, the higher the risk of AVN - up to 80% of proximal pole fractures develop avascular necrosis

Mechanism of Injury

• Fall on an outstretched, dorsiflexed hand (FOOSH) - most common
• Axial load directed along the thumb's metacarpal
• ~12% of scaphoid fractures have an associated injury (distal radius, other carpal bones, carpal instability pattern, or dislocation)

Fracture Location

Clinical Features

Imaging

• Include standard PA, lateral, and dedicated scaphoid view (PA in ulnar deviation - profiles the bone lengthwise)
• Distortion of the radial fat stripe is suggestive of injury
• Up to ~20% of fractures are invisible on initial X-ray

Classification (Instability Criteria)

• Displacement ≥ 1 mm
• Oblique fracture pattern
• Fracture angulation (hump-back deformity on lateral X-ray)
• Associated perilunate injury or carpal instability

Management

Suspected Fracture (X-ray negative, clinically suspected)

Confirmed Fractures

• Below-elbow thumb spica cast
• Thumb inclusion is no longer considered mandatory as routine
• Duration varies by location: distal pole heals fastest; proximal pole fractures need longer immobilisation (up to 12-20 weeks)

• Displacement ≥ 1 mm or instability = consider open reduction and internal fixation (ORIF) with a headless compression screw (e.g., Herbert screw)
• Approach: dorsal approach for proximal pole fractures; volar approach for waist/distal fractures
• Percutaneous screw fixation is increasingly used for non-displaced waist fractures to allow earlier return to activity
• 2025-2026 meta-analyses (PMID 41267607) confirm surgical fixation results in faster functional recovery compared to casting for waist fractures, though union rates are similar

Complications

ED Summary (Tintinalli's)

• Diagnosed fracture: Long arm thumb spica splint in dorsiflexion + radial deviation, urgent orthopaedic referral
• Suspected fracture (normal X-ray): Short arm thumb spica splint in dorsiflexion + radial deviation, orthopaedic follow-up within 1 week ± early advanced imaging

Sources

• Bailey and Love's Short Practice of Surgery, 28th ed.
• Tintinalli's Emergency Medicine: A Comprehensive Study Guide
• Rosen's Emergency Medicine: Concepts and Clinical Practice
• Schwartz's Principles of Surgery, 11th ed.
• Gray's Anatomy for Students

Shoulder Dislocation

Overview

Types

Anatomy

• The glenoid labrum - deepens the socket, provides a suction cup effect
• The inferior glenohumeral ligament - primary restraint against anterior dislocation
• The rotator cuff - dynamic stabiliser (SITS muscles)
• The capsule - reinforced by glenohumeral ligaments

Clinical Features

Anterior Dislocation

• Arm held in slight abduction and external rotation
• Shoulder "squared off" - loss of normal rounded deltoid contour
• Visible/palpable step deformity; humeral head palpable anteriorly
• Patient resists adduction and internal rotation
• Cannot touch the contralateral shoulder with the affected hand

Posterior Dislocation (the "great masquerader")

• Arm held in internal rotation with limited external rotation
• Often missed on AP X-ray - the classic "light bulb sign" on AP view
• Clue in the history: epileptic fit, electric shock, or forceful restraint
• The axillary view is essential and will show posterior displacement

Pre-reduction Imaging

• Age > 40 years
• First episode of dislocation
• Traumatic mechanism (fall >1 flight of stairs, assault, or motor vehicle collision)
• If any of these 3 are present: sensitivity 97.7% for significant fracture

• AP - detects most anterior dislocations and humeral neck fractures
• Axillary view - the single most important view; confirms direction of dislocation; essential for posterior dislocation
• Scapular Y - useful supplement when axillary view cannot be obtained

Associated Injuries (Bony & Soft Tissue)

Hill-Sachs Lesion

• Impaction fracture of the posterolateral humeral head
• Caused by the humeral head striking the anterior glenoid rim during dislocation
• Found in up to 50% of anterior dislocations
• Often seen only on post-reduction films
• Rarely has clinical significance in isolation; can become "engaging" (catches on glenoid rim) if large

Bankart Lesion

• Avulsion of the anteroinferior glenoid labrum from the glenoid rim
• The fundamental pathology underlying recurrent instability
• Soft Bankart = labral detachment alone
• Bony Bankart = labral avulsion with a fragment of the anterior glenoid rim
• Implicated as a primary cause of recurrent anterior dislocation

Other Associated Injuries

Neurovascular Assessment (Mandatory Before and After Reduction)

1. Axillary nerve (most commonly injured) - test pinprick sensation over the "regimental badge" area (lateral deltoid). Motor testing (deltoid contraction) is unreliable because pain prevents it.
2. Radial nerve - check wrist extension
3. Axillary artery - palpate radial pulse; look for axillary hematoma, bruising of lateral chest wall, axillary bruit

If unable to raise the arm after reduction: in the young - suspect axillary nerve injury; in the elderly - suspect rotator cuff tear.

Reduction Techniques

1. Stimson Maneuver (Gravity-Assisted)

• Patient prone on elevated stretcher
• 2.5-5 kg weight suspended from the wrist
• Slow steady traction over 20-30 minutes allows gradual muscle relaxation and reduction
• Advantage: no assistant needed, minimal force applied
• Success rate ~91%; increases to 96% when combined with scapular manipulation
• Disadvantages: time-consuming; prone positioning has airway implications

2. Scapular Manipulation Technique

• Combined with Stimson positioning (prone, arm dependent)
• Operator applies traction on the arm while rotating the scapular tip medially and superiorly with the thumbs
• Success rate >90% in experienced hands; no reported complications in literature
• Works by repositioning the glenoid fossa rather than forcing the humeral head

3. External Rotation Method (Hennepin Technique)

• Patient seated or supine
• Elbow flexed to 90°, arm adducted
• Slowly externally rotate the arm while maintaining gentle traction - reduction often occurs with a palpable clunk
• Gentle, low-force technique; well tolerated

4. Traction-Countertraction

• Assistant applies countertraction via sheet across the chest
• Operator applies steady longitudinal traction along the arm with slight lateral traction
• Classic and reliable; requires two people

5. Hippocratic Method (historical)

• Operator uses foot in the axilla for countertraction while pulling on the arm
• Largely replaced by safer modern techniques due to risk of neurovascular damage

Post-Reduction Care

1. Confirm reduction clinically (restored rounded contour, range of motion) and radiographically
2. Repeat neurovascular examination
3. Immobilise in a broad arm sling (internal rotation) for 2-3 weeks - though there is ongoing debate about whether immobilisation in external rotation reduces recurrence
4. Orthopaedic follow-up - especially important in first-time dislocations (to address recurrence risk and Bankart lesion)
5. Physiotherapy - progressive rotator cuff and shoulder girdle strengthening

Recurrence

Surgical Management (Recurrent Instability)

Arthroscopic Bankart Repair

• Reattaches the detached anteroinferior labrum to the glenoid rim with suture anchors
• Success rate up to 90-95% for recurrence prevention
• A 2024 systematic review (PMID 39428642) confirms good outcomes with arthroscopic Bankart repair
• Knotless vs. knotted techniques: 2025 meta-analysis (PMID 40483425) found comparable recurrence rates
• Inevitably causes some restriction of external rotation

Open Stabilisation (Latarjet / Putti-Platt / Bristow)

• Latarjet procedure: transfers the coracoid process to the anterior glenoid - preferred when there is significant bony glenoid loss (> 20-25%)
• Putti-Platt / Bankart operations: tighten and reinforce the anterior capsular structures
• A 2026 network meta-analysis (PMID 41945260) compared arthroscopic vs. open approaches - both effective; open procedures (particularly Latarjet) offer lower recurrence when significant bone loss is present

Remplissage

• Fills the Hill-Sachs defect with posterior capsule/infraspinatus tendon to prevent engagement
• Used in addition to Bankart repair when Hill-Sachs lesion is large ("engaging")
• Recent RCT data shows significant reduction in recurrence with remplissage + Bankart vs. Bankart alone

Posterior Dislocation - Special Notes

• Often missed - reported delay in diagnosis is common because the AP X-ray can look deceptively normal
• Classic signs: light bulb sign (AP) and trough sign (impaction fracture of anteromedial humeral head = reverse Hill-Sachs)
• Axillary view is diagnostic and must always be obtained if posterior dislocation is suspected
• CT indicated if axillary view cannot be obtained
• Associated with seizures and electric shock because of forceful bilateral muscle contraction in internal rotation

Complications Summary

Sources

• Bailey and Love's Short Practice of Surgery, 28th ed.
• Tintinalli's Emergency Medicine: A Comprehensive Study Guide
• Rosen's Emergency Medicine: Concepts and Clinical Practice
• Roberts and Hedges' Clinical Procedures in Emergency Medicine
• Schwartz's Principles of Surgery, 11th ed.
• Pye's Surgical Handicraft, 22nd ed.