Residency · Residency · Physical Medicine & Rehabilitation
Upper Limb Prosthetic Options and Training
Introduction
Upper limb amputation accounts for approximately 20% of all amputations in the United States, with trauma being the leading cause. Unlike lower limb prosthetics where the primary goal is ambulation, upper limb prosthetics must address complex prehension, proprioception, and cosmesis. Prosthetic rejection rates remain high (20-50%), making appropriate prescription and training essential.
Amputation Levels
Partial hand/finger: Most common level; often functional without prosthesis. Wrist disarticulation: Preserves pronation/supination. Transradial: Below elbow; most successful prosthetic outcomes. Elbow disarticulation: Long lever arm; limits elbow unit options.
Transhumeral: Above elbow; requires prosthetic elbow and terminal device. Shoulder disarticulation and forequarter: Highest complexity; lowest prosthetic use rates.
Prosthetic Categories
Body-Powered Prostheses
Cable-operated via figure-of-nine harness system. Terminal devices: Voluntary-opening (most common) or voluntary-closing hooks. Advantages: Durable, proprioceptive feedback through cable, lower cost, lighter weight. Disadvantages: Limited grip force, harness discomfort, restricted range of motion. Preferred for heavy manual labor and outdoor activities.
Myoelectric Prostheses
EMG signals from residual muscles control motorized components. Two-site (biceps/triceps) or pattern recognition control. Advantages: Improved cosmesis, greater grip force, no harness required. Disadvantages: Heavier, expensive, requires battery charging, moisture-sensitive. Preferred for light to moderate activities, cosmesis priority.
Activity-Specific Prostheses
Sport-specific terminal devices (cycling, swimming, golf). Work-specific tools (adapted for vocational tasks). Musical instrument adaptations.
Passive/Cosmetic Prostheses
Custom silicone restorations with realistic appearance. No active function; body image and symmetry benefits. Lowest rejection rate of all prosthetic types.
| Prosthetic Type | Control Method | Advantages | Disadvantages | Best For |
|---|---|---|---|---|
| Body-powered | Cable/harness | Durable, feedback, lightweight, low cost | Limited grip, harness discomfort | Heavy labor, outdoor use |
| Myoelectric | EMG signals | Better cosmesis, grip force, no harness | Heavy, expensive, moisture-sensitive | Light activity, cosmesis |
| Activity-specific | Varies | Task-optimized | Limited to specific activities | Sports, vocation |
| Passive/Cosmetic | None | Realistic appearance, low rejection | No active function | Body image, symmetry |
Advanced Prosthetic Technologies
Pattern Recognition Control
Multiple EMG electrode arrays classify muscle patterns. Intuitive simultaneous multi-joint control. Commercially available systems (e.g., Coapt pattern recognition). Requires structured training and calibration.
Targeted Muscle Reinnervation (TMR)
Residual nerves transferred to denervated muscle segments. Creates additional EMG control sites. Improves myoelectric control and may reduce phantom/neuroma pain. Ideally performed at time of amputation.
Osseointegration
Titanium implant directly anchored in bone. Eliminates socket; improves proprioception (osseoperception). Requires staged surgical procedure and strict rehabilitation protocol.
Sensory Feedback Systems
Vibrotactile or electrotactile feedback for grip force. Emerging neural interface technologies. Improves functional performance and embodiment.
Prosthetic Training Protocol
Pre-Prosthetic Phase
Residual limb desensitization and shaping. ROM and strengthening of proximal joints. One-handed techniques for ADL independence. Mirror therapy for phantom limb management. Psychosocial counseling and peer support.
Initial Prosthetic Training
Controls training: Learning to activate terminal device (cable pull or EMG signals). Repetitive grasp-release practice with graded objects. Isolated component control before integrated use. Donning and doffing independence.
Functional Training
Bimanual coordination activities (prosthesis as assist hand). ADL tasks: Eating, dressing, grooming, writing. Kitchen and household management. Driving evaluation with adaptive equipment. Vocational tasks and return-to-work planning.
Advanced Training
Sport and recreational activities. Fine motor tasks for myoelectric users. Community integration activities. Maintenance and troubleshooting of prosthetic components.
Outcome Measures
Assessment of Capacity for Myoelectric Control (ACMC). Box and Blocks Test. Southampton Hand Assessment Procedure (SHAP). Disabilities of the Arm, Shoulder, and Hand (DASH). Trinity Amputation and Prosthesis Experience Scales (TAPES).
Complications and Challenges
Prosthetic rejection: Higher in upper limb than lower limb (20-50%). Overuse injuries in the intact contralateral limb. Socket discomfort and skin breakdown. Neuroma pain and phantom sensations. Psychosocial adjustment and body image concerns.
Key Clinical Pearls
- Prosthetic rejection rates are highest for transhumeral and shoulder disarticulation levels; early fitting (within 30 days) improves acceptance. 2. Body-powered prostheses provide superior proprioceptive feedback through cable tension, making them preferred for tasks requiring force modulation. 3. Pattern recognition myoelectric control offers more intuitive multi-joint operation compared to traditional two-site control. 4. Successful upper limb prosthetic use depends more on quality of training and patient motivation than on device sophistication.
References
- Resnik L, Meucci MR, Lieberman-Klinger S, et al. Advanced upper limb prosthetic devices: implications for upper limb prosthetic rehabilitation. Archives of Physical Medicine and Rehabilitation. 2012;93(4):710-717.
- Carey SL, Lura DJ, Highsmith MJ. Differences in myoelectric and body-powered upper-limb prostheses: systematic literature review. Journal of Rehabilitation Research and Development. 2015;52(3):247-262.
- Dumanian GA, Potter BK, Mioton LM, et al. Targeted muscle reinnervation treats neuroma and phantom pain in major limb amputees. Annals of Surgery. 2019;270(2):238-246.
- Biddiss EA, Chau TT. Upper limb prosthesis use and abandonment: a survey of the last 25 years. Prosthetics and Orthotics International. 2007;31(3):236-257.
For the intern
If consulted at 3am about a patient with an upper limb prosthesis, assess for acute issues: skin breakdown, infection at the residual limb, or severe pain suggesting neuroma or compartment syndrome. These require immediate attention. Most prosthetic adjustments, training questions, or device malfunctions can wait until morning when the prosthetist and therapy team are available. Document the concern and ensure the patient is safe without the prosthesis until daytime evaluation.
Common pitfalls
- Prescribing myoelectric prostheses for all patients without considering lifestyle—heavy laborers and outdoor workers often prefer body-powered devices for durability and proprioceptive feedback through cable tension, despite myoelectric devices appearing more advanced.
- Delaying prosthetic fitting beyond 30 days post-amputation—early fitting significantly reduces rejection rates, particularly for transhumeral levels where abandonment approaches 50%.
- Underestimating contralateral limb overuse—the intact arm compensates heavily, leading to repetitive strain injuries, tendonitis, and joint degeneration that require proactive preventive therapy.
- Focusing solely on device technology rather than training quality—patient motivation and structured rehabilitation determine success more than prosthetic sophistication; even advanced pattern recognition systems fail without proper controls training and functional integration exercises.
Make it stick (one 80-word vignette)
The young veteran, a transradial amputee from an IED, looked disheartened. "My myoelectric hand is amazing, but I just can't seem to do anything practical with it. It feels... foreign." His therapist observed his struggle with fine motor tasks, the frustration mounting. "Remember how we started with the body-powered hook? Let's try that for a bit, especially for those heavy-duty shop tasks. Sometimes, simplicity and direct feedback trump high tech. We’ll keep working on both."
If you remember one thing (2 sentences)
Upper limb prosthetic success hinges more on tailored prescription and comprehensive training than on device sophistication alone. Prioritize the patient’s functional goals and lifestyle, recognizing that sometimes a simpler device offers superior utility and acceptance.