Introduction Overview amputations are done urgently and electively to reduce pain, provide independence, and restore function the goals of amputation are preserve functional length preservation of useful sensibility prevention of symptomatic neuromas prevention of adjacent joint contractures early prosthetic fitting early return of patient to work and recreation Epidemiology 1.7 million individuals in the United States with an amputation 80% of amputations are performed for vascular insufficiency major upper-extremity amputations represent 8% of individuals living with limb loss Pathophysiology mechanism of injury trauma most common reason for an upper extremity amputation infection tumor vascular disease most common reason for a lower extremity amputation congenital anomalies wound healing Prognosis outcomes are improved with the involvement of psychological counseling for coping mechanisms involves a close working relationship between rehab physicians, prosthetists, physical therapists, as well as psychiatrists and social workers amputation vs. reconstruction LEAP study impact on decision to amputate limb severe soft tissue injury highest impact on decision-making process absence of plantar sensation 2nd highest impact on surgeon's decision making process not an absolute contraindication to reconstruction plantar sensation can recover by long-term follow-up outcome measure SIP (sickness impact profile) and return to work not significantly different between amputation and reconstruction at 2 years in limb-threatening injuries 25% infection rate Mangled foot and ankle injuries requiring free tissue transfer have a worse SIP than BKA most important factor to determine patient-reported outcome is the ability to return to work About 50% of patients are able to return to work METALS study study focused on military population in response to LEAP study slightly better results in regard to patient-reported outcomes for the amputation group with a lower risk of PTSD more severe limbs were going into salvage pathway military population with better access to prostheses Treatment Nonoperative indications xxx Operative amputation versus limb salvage and replantation indications irreparable loss of blood supply severe soft tissue compromise malignant tumors smoldering infection congenital anomalies amputation vs. limb salvage mangled upper extremity has a far greater impact on overall function than does a lower extremity amputation upper extremity prostheses have much more difficulty replicating native dexterity and sensory feedback provided by the native limb results of nerve repair and reconstruction are more successful in upper extremity than lower extremity superior functional outcomes can be expected in replanted limbs compared with upper extremity amputations diminishing outcomes from replantation are expected the more proximal the level, especially about the elbow level of amputation wrist disarticulation or transcarpal versus transradial amputation wrist disarticulation advantages improved pronation and supination recommended in children for preservation of distal radial and ulnar physes longer lever arm Disadvantage can be difficult to with highly functional prosthesis compared to transradial Although, this may be changing with advancing technology transradial advantages more aesthetically pleasing easier to fit prosthesis (myoelectric prostheses) transhumeral versus elbow disarticulation elbow disarticulation advantages indicated in children to prevent bony overgrowth seen in transhumeral amputations improved suspension and rotational control of prosthesis as a result of preserved distal condyles and intact muscle units Techniques General all named motor and sensory branches within operative field should be identified and preserved can result in improved muscle mass and preserve the ability to create myoelectricsignal for targeted reinnervation myodesis, the process of attaching the muscle-tendon unit directly to bone is recommended a minimum of 5cm of bone distal to a joint is needed to preserve function of that joint successful lengthening procedures have been described with vascularized grafts, but comes with a high complication rate Transcarpal Amputation Transect finger flexor/extensor tendons Anchor wrist flexor/extensor tendons to carpus Wrist disarticulation preserve radial styloid flare to improve prosthetic suspension requires healthy and intact DRUJ Transradial Amputation Middle third of forearm amputation maintains length and is ideal distal 1/3 amputations preserve pronator teres and supinator insertions, but patients rarely exhibit functional rotation Residual 5cm of ulna is required for elbow motion, but at this level will have limited pronation/supination Transhumeral Amputation Maintain as much length as possible Ideal level is 4-5cm proximal to elbow joint Humeral flexion osteotomy can improve prosthetic suspension and functional motion If more proximal amputation is required: At least 5-7cm of residual length is needed for glenohumeral mechanics Shoulder Disarticulation Retain humeral head to maintain shoulder contour Targeted Muscle Reinnervation (TMR) the transfer of functioning nerves that have lost their operational target to intact proximal muscles that serve as biologic amplifiers designed to improve control of myeolectric prostheses used for amputation general transfer amputated large peripheral nerves to reinnervated functionally expendable remaining muscles to create a new discrete muscle signal for the myoelectric prosthesis control benefit of alleviating symptomatic neuroma pain when performed as the primary indication, prevent the development of painful neuromas that develop as a result of disorganized fibroblast and Schwann cell proliferation end to end coaptation to target muscles encourages organized nerve healing pattern of nerve transfer depends on the amputation level, length and function of local peripheral (donor) nerves, and the presence or function of remaining muscle targets surgical technique identify and mobilize donor nerves preserving maximal length, end neuromas are excised and fascicles are trimmed until axoplasmic sprouting of nerve fascicles is noted target muscles are identified and their native motor nerves are transected roughly 1cm proximal to the neuromuscular junction the native motor branch is buried in muscle away from its original target to avoid reinnervation of targeted muscle donor nerve is coapted to the target nerve through tension free end-end repair Complications Wound healing dependent on vascular supply nutritional status immune status improved with albumin > 3.0 g/dL ischemic index > .5 measurement of doppler pressure at level being tested compared to brachial systolic pressure transcutaneous oxygen tension > 30 mm Hg (ideally 45 mm Hg) toe pressure > 40 mm Hg (will not heal if < 20 mm Hg) ankle-brachial index (ABI) > 0.45 total lymphocyte count (TLC) > 1500/mm3 hyperbaric oxygen therapy contraindications include chemo or radiation therapy pressure-sensitive implanted medical device (automatic implantable cardiac defibrillator, pacemaker, dorsal column stimulator, insulin pump) undrained pneumothorax Contractures adjacent joint contractures are common prevent with early aggressive mobilization and position changes Heterotopic ossification more common in trauma-related setting Infection trauma-related amputation have an infection rate of around 34% Postamputation Neuroma occurs in 20-30% of amputees prevent with proper nerve handling at the time of procedure treatment targeted muscle reinnervation a method of guiding neuronal regeneration to prevent or treat post-amputation neuroma pain and improve patient use of myoelectric prostheses Phantom limb pain occurs in 53-100% of traumatic amputations mirror therapy is a noninvasive treatment modality Bone overgrowth most common complication with pediatric amputations treatment prevent by performing disarticulation or using epihphyseal cap to cover medullary canal