GENERAL PRINCIPLES OF AMPUTATION

DR NIKHIL DROLIA

JR I

INTRODUCTION

Amputation : Loss of a limb or part of a limb

The word amputation is derived from the Latin word amputare, "to cut away"

Should not be viewed as a failure of treatment but as the first step in Rehabilitation

Should be performed by the most experienced surgeon in team

HISTORY

Earliest amputation were done on unanesthetized patients & haemostasis attained by crushing or dipping the open stump in boiling oil

Hippocrates was the first to use ligatures Morel’s introduced torniquet in 1674 Lister’s introduced antiseptic technique in

reducing mortality

AMPUTATION

Indications Scoring Surgical Principles

Amputation level Technical Aspects Open Amputations Post operative care

Amputation in children Complications

INDICATIONS

Dead limb – Gangrene

Deadly limb- Wet gangrene ,Spreading cellulitis , Arteriovenous fistula, Other (e.g. malignancy)

‘Dead loss’ limb -Severe rest pain , Paralysis ,Other(e.g. contracture, trauma)

Only absolute indication : irreversible ischemia in diseased or traumatized limb

Peripheral vascular disease Trauma Burns Frostbite Infections Tumors

PERIPHERAL VASCULAR DISEASE

Most common age group 50 to 75 yrs Most patients have concomitant disease processes in

cerebral vasculature, coronary arteries & kidney. Co morbid conditions-diabetes, smoking, prior stroke, prior

major amputation, decreased transcutaneous oxygen levels, decreased ankle-brachail blood pressure index, ulcers.

Most significant predictor of amputation in diabetics is peripheral neuropathy as measured by insensitivity to the Semmes Weinstein 5.07 monofilament.

Perioperative mortality rate-30 % & 40% die within 2 yrs.

TRAUMA

Most common in young patients Male >Female Lange’s absolute indications for amputation in type III C tibial

injuries :o Crush injury with warm ischemia time of > 6 hrs

Relative indications :o Serious associated injurieso Severe ipsilateral foot injuries

Decision as to a limb which can be saved , should be saved or not

Early amputation and prosthetic fitting :◦ Decreased morbidity◦ Fewer operations◦ Shorter hospital stay◦ Decreased hospital costs◦ Shorter Rehabilitation◦ Earlier return to work

Acute trauma : functional stump length of stump must be maintained whenever possible

Necessary for acute or chronic infections which are unresponsive to antibiotics and surgical debridement

Most worrisome infection produced by gas forming bacteria( eg. Clostrdium,streptococcal)

Disability from non healing trophic ulcer , chronic osteomyelitis , infected nonunion

Squamous cell carcinoma from chronic discharging sinus

INFECTION

Limb salvage vs. Amputation◦ Would survival be affected by treatment choice◦ Comparison of short term and long term morbidity◦ Function of salvaged limb◦ Psychosocial consequences

Amputation for malignancy is technically demanding Limb salvage : Disadvantages◦ More extensive surgical procedure ◦ Greater risk of infection ◦ Wound dehiscence◦ Flap necrosis

TUMORS

◦ Increased blood loss◦ Deep venous thrombosis

Late complications :◦ Periprosthetic fractures◦ Prosthetic loosening◦ Graft host nonunion◦ Allograft fractures◦ Leg length discrepancy◦ Late infection

Increased function by increased length of stump vs. Increased complications with shorter stump

Revascularization may aid in increasing length of stump but peripheral bypass surgery may compromise wound healing of a future transtibial amputation

More proximal level of amputation promotes slower walking velocity in order to conserve energy

Amputation should be performed at most distal level if ambulation is main concern

Potential for wound healing best measured by transcutaneous O2 measurement

LEVEL OF AMPUTATION

Ideal length of amputation stump

Above knee amputation : 23-27 cm from greater trochanter or 12 cm from knee

Below knee amputation : 12 -17 cm stump length

2.5cm for every 30 cm of height

Above elbow amputation : 20 cm from shoulder

Below elbow amputation : 18 cm from olecranon

Factors affecting level of stump

Section of bone above a joint may prevent use of best type of artificial joint

Retention of limb remnants below joint which cannot move distal part is not justified

When B/K amputation not possible , disarticulation favored

In ischaemic limbs , level just below distal most pulsation

Ideal stump Conical shape ( ideal shape ) Ideal length Good muscle power Joint should be supple Non adherent scar No fixed deformity Absence of neuroma Bone well covered by muscles Muscular and not flabby Bone covered by muscles , free from infection

What a stump should look like

What a stump should not look like

Efforts should be aimed at

Stump drainage and removal of drain in time

Stump splinting

Proper stump bandaging

Early starting of stump exercises

Stump hygiene and intermittent exposure to air

Tourniquet : Advantageous, contraindicated in ischaemic limbs.

Exsanguinations contraindicated in infected limbs & tumors

Skin Flap Flaps should be kept thick◦ Posterior skin flap should be => anterior skin flap◦ With modern total contact prosthesis , location of scar not important◦ Flap should not be adherent to the underlying bone◦ Preferable to have atypical skin flap than higher level amputation◦ Large dog ears are to be avoided◦ Combined length of flaps should be 1/3 of circumference of limb at level of

amputation

SURGICAL TECHNIQUE

Muscles

◦ Muscles sectioned 5 cm distal to level of intended bone resection

◦ May be stabilized by myoplasty or myodesis

◦ Myoplasty : Suturing muscle to periosteum or fascia of opposing musculature

◦ Myodesis : Suturing muscle or tendon to bone

◦ Myodesis should be performed to have stronger insertion , help maximize strength , minimize atrophy

◦ Myodesed muscle counterbalance antagonists and prevent contractures and maximize residual limb function

◦ Myodesis contraindicated in severe ischemia due to increased risk of wound breakdown

Advantages of Myoplasty/Myodesis

Shape of stump is good

Muscles insulate cut nerve endings and bone from prosthesis

Muscles originating proximally to joint produce better stump mobility and increase leverage

Muscles not acting on joint contract isometrically and assist in venous return

Prevent retraction and painful muscle contractions Phantom pain prevented

Blood vessels

Larger vessels doubly ligated Tourniquet should be deflated before closure Drain preferable for 48-72 hrs

Nerves

After nerve is divided it almost always forms neuroma

Neuroma is painful if traumatized repeatedly

Techniques to prevent neuroma formation : end loop anastomosis , perineural closure , Silastic capping , sealing epineurial tube with butyl-cyanoacrylate , ligation , cauterization or burying nerve ends in muscle /bone

Strong tension should be avoided while stretching

Larger nerves may need ligation for blood vessels

Bone

Excessive periosteal stripping contraindicated

May result in formation of ring sequestrum or bony overgrowth

Bone should be rasped to form a smooth contour- over anterior aspect for below knee , lateral aspect of femur and over radial styloid

Fibula cut slightly proximally to produce conical stump

Skin not closed over level of amputations

First of the at least 2 surgeries used to create functional stump

Required in : Extensive contaminated injuries Infection

Guillotine amputations : all tissue from skin to bone cut at same level ; wound left open for further management ; done as an emergency procedure

Open amputations with flaps where wound open , flaps covered later

OPEN AMPUTATIONS

Treatment of stump crucial from time amputation is completed till definitive prosthesis is fitted

Gradual shift from conventional soft dressings to rigid dressing

Rigid dressing :

POP cast applied to stump at conclusion of surgery ◦ Appropriate padding of all bony prominences◦ Avoiding proximal constriction of ring◦ Use of dependable cast suspension methods

If immediate weight bearing intended , true prosthetic cast should be applied by certified prosthetist

POST OPERATIVE CARE

Advantages of Rigid dressings

Prevent edema at surgical site Protect wound from bed trauma Enhance wound healing Early maturation of stump Decrease postoperative pain Allow early mobilization from bed Prevent formation of knee flexion contractures

Drains removed at 48 hrs post op

Stump is elevated by raising foot end

`Avoid leaving stump in dependent position

RIGID DRESSING

Prevent flexion or abduction contractures of hip

2nd post op day : muscle setting and joint mobilization exercises begun

Time for prosthesis application depends upon : Age Strength Agility Patient’s ability to protect stump from excessive weight bearing

Early unprotected weight bearing may lead to sloughing of skin or delayed wound healing

Cast should be removed after 7-10 days

POST OPERATIVE CARE

Hematoma Infection Wound Necrosis Contractures Pain Phantom limb sensation Dermatological problems

COMPLICATIONS

Hematoma: Prevented by rigid dressing , meticulous hemostasis May delay wound healing Serve as nidus for infection

Infection : More common in ischemic ,diabetic limbs Deep wound infection should be treated with immediate debridement Delayed closure may be difficult because of edema Smith and Burgess method of closing central 1/3 of wound and leaving rest

packed open Wound Necrosis:

Nutritional supplementation , TLC , albumin counts Necrosis of skin edge < 1 cm can be treated conservatively Discontinue prosthetic until wound healed If severe necrosis with loss of bone coverage , wedge resection indicated

Contractures: Prevented by proper stump positioning , gentle passive stretching , exercises Increased ambulation reduces contractures May need wedging casts or surgical release of contracted sutures

Dermatological problems : Contact Dermatitis Bacterial folliculitis Epidermoid cysts Verrucous hyperplasia

Pain : Phantom limb , Phantom pain, residual pain , pain from distant site Back ache more common in amputees Residual pain more often due to improper fitting Painful neuroma usually is easily palpable Phantom limb :

Very common Usually not very bothersome Telescoping Phantom limb pain bothersome , present mostly in proximal level amputations Conservative measures tried

Infection Wound necrosis

Most often due to trauma followed by neoplasms , infection General body growth and stump growth important Considerations :

Preserve length as much as possible Preserve important growth plates Prefer disarticulation rather than amputation Preserve knee joint whenever possible Stabilize and normalize proximal portion of limb

To prevent stump overgrowth , myodesis must be preferred at the time of surgery

Terminal overgrowth : appositional spike like new bone formation Regular prosthetic checking

AMPUTATIONS IN CHILDREN

REFERENCES

Campbell Apley’s Google