UPPER LIMB AMPUTATION
Preserve Sensation and Length | Functional Priorities | Prosthetic Integration | Targeted Muscle Reinnervation
UPPER LIMB AMPUTATION LEVELS
Critical Must-Knows
- Functional priority in upper limb: Sensation greater than motion greater than length (opposite to lower limb)
- Preserve elbow joint whenever possible - essential for prosthetic function and ADLs
- Replantation vs amputation: Consider indications including thumb, multiple digits, child, clean sharp amputation
- TMR (Targeted Muscle Reinnervation): Improves myoelectric prosthetic control and reduces neuroma pain
- Body-powered vs myoelectric prostheses: Different advantages - body-powered provides sensory feedback
Examiner's Pearls
- "Upper limb amputees use prostheses less than lower limb amputees - functional adaptation common
- "Replant thumb at all costs - worth the entire hand functionally
- "Transradial amputation maintains pronation-supination if distal radioulnar joint preserved
- "Phantom limb pain affects up to 80% of upper limb amputees - early intervention essential
Clinical Imaging
Imaging Gallery
Critical Upper Limb Amputation Exam Points
Sensation Over Length
Upper limb priorities differ from lower limb. The sensate hand is critical for function - a shorter stump with preserved sensation may be more functional than a longer insensate stump. Always preserve sensate tissue where possible. This contrasts with lower limb where length for weight-bearing and prosthetic fitting is paramount.
Replantation Decision
Know the replantation indications: Thumb (most important single digit), multiple digits, hand through wrist, pediatric (any level), clean sharp amputation. Contraindications: Multi-level injury, severe crush/avulsion, prolonged warm ischaemia (greater than 6 hours for digits), life-threatening injuries, severe comorbidities.
Prosthetic Considerations
Body-powered prostheses provide proprioceptive feedback and are more durable. Myoelectric prostheses offer cosmesis and grip strength but lack sensory feedback. Many upper limb amputees reject prostheses and adapt functionally. Elbow preservation is essential for any prosthetic control.
Targeted Muscle Reinnervation
TMR (Targeted Muscle Reinnervation) is an emerging technique where transected nerves are transferred to nearby muscle targets. This provides intuitive myoelectric control, reduces phantom pain, and prevents neuroma formation. Know this as a contemporary technique for transradial and transhumeral levels.
Upper Limb Amputation Level Selection Guide
| Level | Key Considerations | Functional Outcome | Prosthetic Options |
|---|---|---|---|
| Finger amputation | Preserve length, preserve insertion of FDS/FDP | Good function, cosmesis concern | Passive cosmetic, rarely active |
| Ray amputation | Improves grip for adjacent digits, cosmesis | Narrower hand, may improve function | Cosmetic finger prosthesis |
| Wrist disarticulation | Preserves pronation-supination, long lever arm | Excellent residual function | Body-powered or myoelectric |
| Transradial (BEA) | Preserve elbow, minimum 5cm for pronation | Good prosthetic control with elbow intact | Myoelectric with multiple grip patterns |
| Elbow disarticulation | Long lever arm, no bone cut | Bulky prosthetic elbow, limited cosmesis | External locking elbow |
| Transhumeral (AEA) | Preserve length for prosthetic suspension | Major functional loss, reduced prosthetic use | Myoelectric with TMR, body-powered |
| Shoulder/Forequarter | Oncological indication most common | Very limited prosthetic use | Cosmetic shoulder cap |
SENSEUpper Limb Amputation Priorities
Memory Hook:Upper limb makes SENSE - Sensation and Elbow preservation are the priorities
THUMB PLUSReplantation Indications
Memory Hook:THUMB PLUS all its fingers equals replantation success
GRASPProsthetic Selection Factors
Memory Hook:Help patients GRASP their prosthetic options - matching function to need
Overview and Epidemiology
Upper limb amputation is the surgical removal of part or all of the upper extremity. Unlike lower limb amputation where weight-bearing function is paramount, upper limb amputation surgery must prioritize preservation of sensation and fine motor function to maximize hand utility.
Epidemiology:
- Upper limb amputations are approximately 5 times less common than lower limb
- Trauma is the most common indication (80%) - industrial accidents, motor vehicle trauma
- Males predominate (3:1 ratio) due to occupational exposure
- Mean age is younger than lower limb amputees (occupational injury)
- Finger and partial hand amputations are most common
Upper vs Lower Limb Amputation Philosophy
Upper limb amputation differs fundamentally from lower limb. In the lower limb, the goal is weight-bearing and locomotion - length and prosthetic fitting are priorities. In the upper limb, sensation and fine motor control are essential for hand function. A shorter sensate stump may be more functional than a longer insensate one. Many upper limb amputees adapt without prostheses.
Indications:
Trauma (80%)
- Industrial accidents: Crush, avulsion, saw injuries
- Motor vehicle trauma: Mangled extremity
- Burns: Electrical, thermal with vascular compromise
- Frostbite: Severe cold injury with gangrene
- Failed replantation or reconstruction
Non-Traumatic Causes
- Malignancy: Primary bone/soft tissue sarcoma
- Infection: Gas gangrene, necrotizing fasciitis, refractory osteomyelitis
- Vascular: Rare in upper limb (brachial artery occlusion, Buerger's disease)
- Congenital: Constriction band syndrome, amniotic band syndrome
Contraindications to Replantation (Favour Amputation):
- Multi-level or avulsion injury (poor prognosis)
- Severe crush injury with tissue destruction
- Warm ischaemia time greater than 6 hours for digits (12 hours if cooled)
- Life-threatening associated injuries requiring resuscitation
- Severe medical comorbidities precluding prolonged surgery
- Self-inflicted injuries (relative - psychiatric assessment needed)
Pathophysiology and Functional Considerations
Functional Anatomy Considerations
Understanding the functional requirements at each level is essential for amputation planning in the upper limb.
Functional Loss by Amputation Level
| Level | Function Lost | Function Preserved | Prosthetic Potential |
|---|---|---|---|
| Finger (distal to MCP) | Fine pinch, sensation at fingertip | Power grip, adjacent finger function | Limited - cosmetic mainly |
| Hand (transmetacarpal) | All grip patterns, opposition | Wrist motion, pronation-supination | Partial hand prosthesis |
| Wrist disarticulation | Grip, wrist motion | Full pronation-supination (50 degrees each) | Good terminal device control |
| Transradial | Grip, wrist, partial forearm rotation | Elbow flexion-extension | Excellent myoelectric control |
| Transhumeral | All below-elbow function | Shoulder motion only | Limited - major functional loss |
| Shoulder disarticulation | All arm function | Trunk and scapular motion | Very limited prosthetic use |
Nerve Handling and Neuroma Prevention
Neuroma Formation:
- Inevitable after nerve transection - regenerating axons form disorganized mass
- Painful neuroma develops when nerve end is in mobile or pressure-bearing area
- Upper limb neuromas are particularly problematic due to constant use
- Prevention is key - proper nerve management at initial surgery
Targeted Muscle Reinnervation (TMR):
Targeted Muscle Reinnervation
TMR involves transferring transected nerves to nearby muscle motor points. The muscle serves as a biological amplifier - when the patient thinks of moving their missing hand, the reinnervated muscle contracts, providing strong EMG signals for myoelectric prosthetic control. TMR also prevents neuroma formation and reduces phantom pain by providing the transected nerve a target.
TMR Nerve Transfers by Level:
- Transradial: Median and ulnar nerves to remaining forearm muscle motor points
- Transhumeral: Median to short head biceps, ulnar to brachialis, radial to lateral triceps
- Shoulder: Musculocutaneous to clavicular pectoralis major, median/ulnar to sternal pectoralis
Phantom Limb Phenomena
Phantom Limb Sensation:
- Nearly universal after upper limb amputation
- Non-painful awareness of missing limb
- Typically diminishes over time
Phantom Limb Pain (PLP):
- Affects 50-80% of upper limb amputees
- Character: Burning, cramping, shooting, electric
- Risk factors: Pre-amputation pain, traumatic mechanism, anxiety/depression
- Prevention: Perioperative nerve blocks, TMR at initial surgery
Phantom Pain Prevention
Early intervention is key for phantom limb pain. Perioperative regional anaesthesia (brachial plexus block, epidural) may reduce incidence. TMR at primary amputation reduces both neuroma pain and phantom pain. Mirror therapy should be initiated early in rehabilitation.
Clinical Presentation and Assessment
Indications by Level
Finger and Ray Amputation
Indications:
- Irreparable crush or avulsion injury to digit
- Failed replantation
- Severe infection (septic arthritis, osteomyelitis)
- Tumour requiring local excision
- Painful non-functional digit (neuroma, cold intolerance)
Assessment:
- Vascularity of adjacent tissue
- Tendon and nerve integrity
- Level of injury (through bone vs joint)
- Replantation candidacy (thumb prioritized)
Functional Considerations:
- Thumb: Most important digit - 50% of hand function. Replant at all costs
- Index finger: Precision pinch, pointing. Loss well compensated by long finger
- Long finger: Central pillar of grip. Loss affects both power and precision
- Ring finger: Power grip contribution. Ray amputation may improve function
- Little finger: Ulnar border, power grip. Preserve for cupping function
Replantation Decision-Making
Replantation vs Amputation Decision Factors
| Factor | Favours Replantation | Favours Amputation |
|---|---|---|
| Mechanism of injury | Clean, sharp cut (guillotine) | Crush, avulsion, multi-level |
| Ischaemia time | Less than 6 hours (digit), less than 12 hours (major limb) | Prolonged warm ischaemia |
| Level | Thumb, multiple digits, proximal (wrist/forearm) | Single digit (index, long, ring) |
| Patient age | Pediatric (excellent regeneration), young adult | Elderly with comorbidities |
| Patient factors | Non-smoker, compliant, motivated | Smoker, non-compliant, unrealistic expectations |
| Associated injuries | Isolated limb injury, stable patient | Polytrauma, life-threatening injuries |
Investigations
Investigation Protocol for Upper Limb Amputation Planning
Essential for all cases:
- AP and lateral of affected limb segment
- Assess bone level, fracture pattern, foreign bodies
- For trauma: Full trauma series if indicated
- Chest radiograph if oncological (metastatic workup)
When vascular injury suspected:
- Hand-held Doppler assessment of radial, ulnar, digital arteries
- Allen test for palmar arch competency
- CT angiography if revascularization being considered
- Warm ischaemia time documentation critical
Selected cases:
- MRI: Tumour staging, soft tissue extent
- CT: Bone detail, fracture pattern, foreign bodies
- PET-CT: Oncological staging if sarcoma suspected
Preoperative baseline:
- Full blood count, coagulation studies
- Group and hold (cross-match if major amputation)
- Urea, electrolytes, glucose
- CRP if infection suspected
- Muscle enzymes if crush injury (rhabdomyolysis risk)
Replantation Workup
For potential replantation, investigations are time-critical. Obtain X-rays of both amputated part and stump. Document exact ischaemia time. Cool the amputated part correctly (wrapped in saline-moistened gauze, in plastic bag, on ice - not directly on ice or in water). Activate replantation team while investigations proceed.
Management Principles
Level Selection Principles
Goals in Upper Limb Amputation:
- Preserve sensation wherever possible
- Preserve elbow joint (critical for function)
- Preserve length for prosthetic fitting
- Ensure durable soft tissue coverage
- Prevent neuroma formation (TMR when possible)
- Optimize for prosthetic or functional adaptation
Upper Limb Amputation Levels - Detailed
| Level | Length Requirements | Key Structures to Preserve | Prosthetic Implications |
|---|---|---|---|
| Finger | Maximum length through bone | Preserve FDS/FDP insertions if possible | Cosmetic prosthesis only |
| Ray amputation | Through metacarpal base | Adjacent finger tendons and nerves | Improves grip, cosmetic option |
| Wrist disarticulation | Through radiocarpal joint | Distal radioulnar joint (pronation-supination) | Excellent control, bulbous end |
| Transradial | Minimum 5cm from olecranon | Elbow joint, biceps/brachialis insertions | Ideal for myoelectric, TMR possible |
| Elbow disarticulation | Through joint, preserve condyles | Humeral length, epicondyles for suspension | External elbow lock, bulky |
| Transhumeral | Minimum 10cm from acromion | Deltoid insertion if possible | TMR improves control significantly |
| Shoulder disarticulation | At glenohumeral joint | Scapula, clavicle for cosmetic cap | Limited prosthetic use |
Surgical Management
Digital Amputation Technique
Indications:
- Irreparable trauma to digit
- Severe infection (septic arthritis, osteomyelitis)
- Non-viable replant
- Tumour requiring excision
Level Selection:
- Preserve maximum length
- Through bone preferred to through joint (cosmesis)
- Preserve FDP/FDS insertions when possible
Digital Amputation Steps
Fish-mouth or lateral incisions:
Create volar and dorsal flaps of equal length, or lateral flaps for side-to-side closure. Volar flap slightly longer provides better coverage.
Identify and protect structures:
Divide flexor and extensor tendons proximal to skin level. Identify digital nerves and arteries.
Ligate vessels, handle nerves:
Ligate or cauterize digital arteries. Apply gentle traction to digital nerves, transect sharply, allow retraction.
Divide bone smoothly:
Use bone cutter or saw. Rongueur to smooth edges. Bone level proximal to skin level for tension-free closure.
Tension-free skin closure:
Close volar to dorsal skin with interrupted nylon. Bulky dressing with aluminium finger splint protection.
Technical Pearls:
- Thumb: Preserve maximum length - every millimeter counts
- Index ray amputation: Improves cosmesis and grip width
- Ring ray amputation: Narrows hand, may improve power grip
- Volar flap: More durable than dorsal skin for tip coverage
Prosthetic Considerations
Prosthetic Options by Level
Prosthetic Options for Upper Limb Amputation
| Level | Prosthetic Type | Terminal Device | Control Mechanism |
|---|---|---|---|
| Finger/Partial hand | Passive cosmetic silicone | Cosmetic fingers | None - passive |
| Wrist disarticulation | Body-powered or myoelectric | Hook or hand | Cable or EMG |
| Transradial | Myoelectric multi-articulating hand | i-Limb, bebionic, TASKA | 2-site EMG or pattern recognition |
| Elbow disarticulation | Body-powered or hybrid | Hook or hand with external elbow | Cable for elbow, EMG for TD |
| Transhumeral | Myoelectric with TMR | Multi-articulating hand and elbow | Pattern recognition optimal |
| Shoulder | Cosmetic cap | None functional | Cosmetic restoration only |
Body-Powered vs Myoelectric Prostheses
Body-Powered Prostheses
Advantages:
- Provides proprioceptive feedback through cable
- More durable, reliable
- Lower cost and maintenance
- Works in wet and dirty environments
- Lighter weight
Disadvantages:
- Limited grip strength
- Less cosmetic
- Requires harness (uncomfortable for some)
- Fatiguing with prolonged use
Myoelectric Prostheses
Advantages:
- Better cosmesis
- Higher grip strength
- Multiple grip patterns (modern hands)
- No harness required
- Less physical effort for operation
Disadvantages:
- No sensory feedback
- Battery dependent
- Cannot use in wet environments
- Higher cost and maintenance
- Heavier
Prosthetic Rejection
Upper limb amputees reject prostheses more often than lower limb amputees (30-50% rejection rate). Many adapt functionally using their residual limb and contralateral hand. Body-powered prostheses are rejected less often than myoelectric due to feedback and reliability. Early prosthetic fitting improves long-term use. Patient goals and occupation should guide prosthetic selection.
Complications
Wound-Related Complications
Wound Complications
| Complication | Incidence | Risk Factors | Management |
|---|---|---|---|
| Wound infection | 5-10% | Diabetes, contamination, crush injury | Antibiotics, debridement, revision if needed |
| Wound dehiscence | 5% | Tension, poor vascularity, malnutrition | VAC therapy, revision, skin graft if needed |
| Flap necrosis | Variable | Crush injury, arterial disease, tension | Debridement, revision to higher level |
| Haematoma | 5% | Anticoagulation, inadequate hemostasis | Aspiration or evacuation |
Prevention:
- Tension-free closure
- Adequate hemostasis
- Avoid closure over bone prominences
- Proper flap design
Evidence Base and Key Studies
Targeted Muscle Reinnervation for Neuroma Prevention
- RCT comparing TMR to standard neurectomy in major limb amputation
- TMR group had significantly lower neuroma pain
- TMR group had lower phantom limb pain at 1 year
- TMR also provides improved myoelectric control sites
- Supports TMR at primary amputation
Upper Limb Replantation Outcomes
- Review of 347 upper limb replantations over 20 years
- Overall survival rate 87%
- Thumb replantation survival 94%
- Proximal replantations (wrist and above) had 82% survival
- Functional outcomes correlated with level and mechanism
Prosthetic Use and Rejection Rates
- Systematic review of upper limb prosthetic rejection
- Body-powered rejection rate: 26%
- Myoelectric rejection rate: 23%
- Passive/cosmetic rejection rate: 39%
- Early fitting correlates with long-term acceptance
- Pediatric patients have higher acceptance rates
Mirror Therapy for Phantom Limb Pain in Upper Limb Amputees
- RCT of mirror therapy for phantom limb pain
- Significant reduction in phantom pain with mirror therapy
- Effects correlated with changes in cortical representation
- Maintained at 6-month follow-up
- Simple, non-invasive intervention
Exam Viva Scenarios
Practice these scenarios to excel in your viva examination
"A 28-year-old right-hand dominant male presents to the emergency department after his right hand was caught in an industrial press. Examination reveals crush injury to all fingers at the level of the proximal phalanges with devitalized tissue. The thumb metacarpal is fractured but the thumb itself is intact. There is no distal circulation to the fingers. The amputated finger segments have been retrieved but are severely crushed. How would you manage this patient?"
"You are performing a transradial amputation for a 45-year-old woman with sarcoma of the distal radius. The oncology team requires a margin of 5cm proximal to the tumour, which leaves approximately 12cm of forearm from the elbow. Describe your surgical technique, focusing on nerve management and optimization for prosthetic function."
"A 16-year-old boy presents 4 hours after a clean guillotine amputation of his right thumb at the level of the proximal phalanx from a circular saw accident at his father's workshop. The amputated part has been kept in a plastic bag on ice. What are the indications for replantation here, and describe your management approach."
Australian Context
Upper limb amputation in Australia occurs predominantly as a result of occupational trauma, with industrial and agricultural injuries being common mechanisms. The Australian trauma system provides excellent access to microsurgical replantation services through major metropolitan centers, with all capital cities having replantation-capable units. The Australian Hand Surgery Society maintains standards for replantation services and training.
Management of upper limb amputees involves comprehensive multidisciplinary rehabilitation. Prosthetic services are provided through state-funded limb centers and the National Disability Insurance Scheme (NDIS) for eligible patients. Modern myoelectric prostheses including multi-articulating hands (i-Limb, bebionic) are available through NDIS funding, though approval processes require demonstration of functional benefit. TMR surgery is available at several Australian centers, with growing expertise particularly in Melbourne and Sydney.
Prevention remains a priority in the Australian context, with WorkSafe agencies in each state regulating workplace safety standards. Agricultural injuries remain significant in rural Australia, with delayed presentation and transfer times affecting replantation viability. The Royal Australasian College of Surgeons maintains guidelines for trauma systems and appropriate transfer protocols for potentially replantable injuries.
Upper Limb Amputation - Exam Quick Reference
High-Yield Exam Summary
Key Priorities
- •Sensation GREATER THAN motion GREATER THAN length (opposite to lower limb)
- •Preserve elbow - loses 50% function if amputated above
- •Replant thumb at all costs - 50% of hand function
- •TMR prevents neuroma and phantom pain, improves prosthetic control
Replantation Indications (THUMB PLUS)
- •Thumb - single most important digit
- •Multiple digits, hand/wrist level
- •Pediatric patients (any level)
- •Clean sharp mechanism, short ischaemia time
Level-Specific Pearls
- •Finger: Preserve FDS/FDP insertion, volar flap for coverage
- •Wrist disarticulation: Preserves pronation-supination (DRUJ intact)
- •Transradial: Minimum 5cm from elbow, ideal for TMR and myoelectric
- •Transhumeral: Preserve deltoid insertion, TMR essential for function
Nerve Management
- •Standard: Traction neurectomy - pull, sharp transection, allow retraction
- •TMR: Transfer median to biceps, ulnar to brachialis, radial to triceps
- •Position nerves away from scar and pressure areas
- •TMR reduces both neuroma AND phantom limb pain
Prosthetic Considerations
- •Body-powered: Proprioceptive feedback, durable, works wet
- •Myoelectric: Cosmesis, grip strength, multiple patterns, no feedback
- •30-50% upper limb amputees reject prostheses - functional adaptation common
- •Early fitting improves long-term acceptance
Complications to Know
- •Phantom limb pain: 50-80%, mirror therapy effective, gabapentinoids
- •Neuroma: Prevented by TMR or traction neurectomy
- •Contracture: Elbow flexion (transhumeral) - early ROM essential
- •Prosthetic rejection: Common - address patient goals and expectations