Describe Amputations in detail.

Definition & Indications

An amputation is the surgical removal of part or all of a limb. Although it is often seen as a failure of treatment, a well-performed amputation is a reconstructive procedure that relieves suffering and restores function with a prosthesis. The indications are classically remembered as the ‘three Ds’ — Dead (dead limb: critical ischaemia/gangrene, e.g. Peripheral vascular disease, diabetes), Dangerous (a limb threatening life: spreading sepsis/gas gangrene, malignancy, crush with rhabdomyolysis), and Damn nuisance (a useless, painful or deformed limb worse than no limb: intractable pain, gross deformity, non-functional paralysis).

Levels & Types

Amputations are described by level (e.g. Below-knee, above-knee, Syme’s at the ankle, trans-metatarsal; below- or above-elbow). The level is chosen to remove all diseased/non-viable tissue while preserving the longest, most functional stump that will heal and take a prosthesis. A below-knee amputation (preserving the knee) gives far better function and energy-efficient walking than an above-knee amputation, so the knee is saved whenever possible. Amputations may be provisional (guillotine) in infected/emergency cases (leaving the wound open, closed later) or definitive with primary shaping and closure.

Principles of a Good Stump

A good stump is the key to successful prosthetic use. Principles: adequate length with a well-padded, non-adherent scar placed away from pressure areas; myoplasty/myodesis (securing opposing muscles over the bone end) for a stable, powered, cylindrical stump; sectioning nerves cleanly under tension so they retract (to keep the inevitable neuroma away from pressure); secure haemostasis; and appropriate bone shaping (bevelling). Postoperative oedema control, stump shaping and early rehabilitation prepare the stump for a prosthesis.

Complications

Early: haematoma, wound infection, skin-flap or stump necrosis (especially in ischaemic limbs), and reactionary haemorrhage. Late: a painful or symptomatic neuroma, phantom limb sensation and phantom limb pain, stump ulceration (from a poorly fitting prosthesis), flexion contractures of the joint above (prevented by positioning and physiotherapy), and psychological adjustment problems.

Rehabilitation

Amputation is only the first step; rehabilitation determines the outcome. A multidisciplinary team manages pain, conditions and shapes the stump, provides a prosthesis and gait training, and supports psychological adjustment and return to work and daily life. Early involvement of physiotherapy and prosthetics optimises independence.

Special Situation — the Ischaemic Limb

In amputations for peripheral vascular disease and diabetes — the commonest indication in adults — the guiding principle is a conflict between amputating low enough to preserve function and high enough to reach tissue with a blood supply that will heal. Level selection is aided by clinical assessment of skin perfusion and, where needed, vascular studies. These patients are often elderly with multiple comorbidities, so perioperative optimisation, meticulous handling of ischaemic tissue and diabetic control are as important as the operation itself for a stump that heals.

The 3 Ds — dead, dangerous, damn nuisance.

• Amputation is reconstructive; indications = 3 Ds: Dead, Dangerous, Damn nuisance.
• Choose the level to remove disease yet keep the longest functional stump that heals.
• Save the knee (below-knee walks far more efficiently than above-knee).
• Good stump: length, padded mobile scar, myoplasty, nerves cut under tension, shaped bone.
• Complications: neuroma, phantom pain, stump ulcer, flexion contracture; rehab is key.