Upper Limb Amputations

General Principles

 

All possible length should be preserved consistent with clinical judgement

- function of amputated stumps decrease progressively with each higher level of amputation 

- prosthetic rejection by patient increases with the more proximal amputations

- most ADL'S can be performed adequately with one limb, so don't use prosthesis

- all nerves are drawn distally into wound & sectioned so they retract well proximally to bone level of amputation

 

Transcarpal

 

Concept

- can preserve flexion / extension of radiocarpal joint which transmitted partly to prosthesis

 

Technique

- fashion long palmar, short dorsal flaps in ratio (2:1)

- divide tendons under tension

- divide nerves well proximal to amputation

- divide vessels just proximal to amputation bony level

- divide bones and smooth / round edges

- anchor wrist flexor and extensor tendons to remaining carpal bones in line of pull to allow wrist flexion/extension

 

Wrist disarticulation

 

Technique

- fashion long palmar, short dorsal flaps (2:1)

- skin apices 1cm distal to ulnar and radial styloids

- divide vessels, nerves, tendons and open radiocarpal joint

- resect radial / ulnar styloid processes & smoothen bony processes to form a smooth rounded contour

- protect distal radioulnar joint including triangular ligament to preserve supination/ pronation

- insert suction drain and skin closure 

 

Forearm

 

Forearm amputationForearm amputation

 

Concept

- preserve as much length as possible (forearm rotation and strength proportional to length retained)

- if circulation compromised, amputation through distal 1/3 forearm are less likely to heal

- distally skin is thin and subcutaneous tissue scant

- junction mid and distal thirds good compromise for amputation level

- short 'below elbow stump' (up to 3.8-5cm long) preferable to through or above elbow

- important to preserve elbow joint

 

Distal

- skin incision apices at level of bone cut

- ligate radial / ulnar arteries and divide nerves under tension then transverse bone cuts and rasp edges

- fashion FDS flap long enough to be carried around bone ends 

- section rest of muscles at level of bone

- suture FDS flap over dorsal fascia

 

Proximal third

- fashion equal volar and dorsal flaps ideally

- divide muscle bellies distal to bone cuts to allow for retraction

- transverse bone cuts and rasp edges

- if stump is proximal to bicipital radial tuberosity, then resect distal 2.5cm of biceps tendon

- this lengthens stump functionally and enhances prosthetic fitting

- leaves brachialis as principle elbow flexor

 

Krukenburg's Amputation

- performed as a secondary procedure in 'below elbow' amputation

- converts forearm amputation into radial and ulnar pincers

- need at least 10 cm from olecranon tip & elbow flexion contracture <70o

- classically used in blind bilateral below elbow amputee

 

Elbow disarticulation

 

Concept

- good level for amputation due to easy fitting of prosthesis to distal humeral flare

- allows transmission of humeral rotation to the prosthesis (preferable to a more proximal humeral amputation)

- due to modern prosthesis techniques, disarticulation is preferred to proximal humeral amputation

 

Technique

- equal anterior and posterior flaps with apices at level  of humeral epicondyles

- posterior flap extents 2.5cm. distal to olecranon tip

- anterior flap extends just distal to biceps tendon insertion

- divide lacertus fibrosis

- reflect distally flexor origin off medial epicondyle

- expose neurovascular bundle on medial side of biceps tendon

- divide brachial artery, median and ulnar nerves proximal to elbow joint

- free the insertions of biceps and brachialis from radius / ulna

- divide radial nerve as lies between brachialis and BR

- divide transversely extensor mass 6 cm distal to joint line

- divide posterior fascia and triceps tendon near tip of olecranon

- divide anterior joint capsule to complete the disarticulation & remove the forearm

- leave intact articular cartilage of humerus 

- suture triceps tendon anteriorly to biceps and brachialis

- suture extensor muscle mass medially to flexor origin muscle stump

 

Can add distal humeral osteotomy

- create anterior angulation 45o

- aids prosthesis fitting / reduces need for shoulder harness

 

Above Elbow

 

Concepts

- most important to preserve limb length

 

Above elbow prosthesis

- elbow-lock mechanism stabilises joint in full extension, flexion or in a position between

- lock mechanism extends 3.8 cm distally from the end of the prosthetic socket

- therefore most distal bone section should be 3.8cm from end of humerus to allow room for this mechanism

 

Supracondylar level

- equal anterior and posterior flaps at length 1/2 diameter of arm at that level

- artery and nerve divided proximal to level of resection

- divide anterior compartment muscle flaps 1.3cm distal to bone section level so they retract to this level

- free triceps insertion off olecranon & preserve as a long flap

- transverse bone cut 3.8 cm proximal to humerus end and rasp edges

- suture long flap of triceps anteriorly to the fascia over anterior muscles

 

Proximal to supracondylar level

- equal anterior and posterior flaps

- divide anterior compartment muscles 1cm distal to bone cut to allow retraction

- divide triceps 3.8-5cm distal to bone cut

- suture triceps anteriorly over bone end to anterior muscle fascia

 

Shoulder amputations

 

Concept

- shoulder amputation levels require fitting as if for joint disarticulation

- Prosthetic function is severely impaired at shoulder level 

- prostheses are used primarily as a holding device when performing activities with both hands

 

Through surgical neck

 

Position

- patient supine with sandbag beneath shoulder (patient's back 45 degrees to table)

 

Anterior incision

- incision from coracoid process, along anterior deltoid border to its insertion

 

Posterior incision

- along posterior deltoid border to posterior axillary fold

- connect the two limbs of incision by a second incision that passes through axilla then incise anteriorly through axilla

 

Superficial dissection

- ligate cephalic vein, separate deltoid and pectoralis major in deltopectoral groove

- reflect deltoid laterally

- divide pectoralis tendon at its insertion and reflect medially

 

Expose neurovascular bundle

- develop plane between pectoralis minor and coracobrachialis to expose neurovascular bundle

- divide axillary artery and vein inferior to pectoralis minor

- divide nerves on stretch so they retract proximal to pectoralis minor

 

Deep dissection

- divide deltoid insertion and reflect deltoid / lateral skin flap superiorly

- divide teres major and latissimus dorsi at bicipital groove

- divide short and long heads of biceps, triceps and coracobrachialis 2 cm distal to bone cut

- section bone at surgical NOH

 

Closure

- suture long head triceps, both heads biceps and coracobrachialis over end of humerus

- suture pectoralis major tendon to bone end

- bevel deltoid to allow skin closure

 

Shoulder disarticulation

 

Position and incision

- as above

 

Superficial dissection

- ligate cephalic vein

- separate deltoid and pectoralis major

- retract deltoid laterally and divide insertion

- divide pectoralis major tendon at insertion and reflect medially

 

Neurovascular bundle

- divide conjoint tendon and P minor on coracoid

- expose neurovascular bundle

- ligate axillary artery and vein and thoracoacromial artery

- divide nerves on stretch so they retract proximal to pectoralis minor

 

Deep dissection

- reflect deltoid insertion superiorly to expose shoulder joint capsule

- divide teres major and latissimus dorsi at insertions

- after internally rotating arm divide posterior rotator muscles at insertion & posterior capsule 

- place arm in extreme external rotation & divide subscapularis anterior joint capsule

- divide triceps at infraglenoid tubercle insertion & divide inferior capsule to severe the limb

 

Closure

- suture all muscles across glenoid to fill the hollow out (deltoid to inferior glenoid)

- may need to trim prominent anterior acromion to produce smoothly rounded contour

- drain deep to deltoid

 

Forequarter

 

Concept

- shoulder girdle amputation

- consists of removal entire shoulder girdle / upper limb in interval between scapula and thoracic wall

- indicated for malignant tumour involving upper humerus or shoulder joint

- atypical skin flaps often used, may require axillary skin grafts

 

Anterior Approach

 

Incision

 

Upper limb of incision

- begins at lateral border sternocleidomastoid

- extends laterally along anterior aspect clavicle

- back across AC joint

- over superior aspect shoulder to scapular spine

- inferiorly along vertebral border of scapula to inferior angle

 

Lower limb

- starts at mid 1/3 clavicle

- runs inferiorly in deltopectoral groove 

- runs posteriorly through axilla to join upper limb incision at inferior scapular angle

 

Superficial Dissection

- subperiosteally dissect out clavicle 

- cut at lateral border sternocleidomastoid and through AC joint

- external jugular divided or retracted

 

Deep Dissection

- release pectoralis major off humerus and pectoralis minor off coracoid to expose neurovascular structures

- ligate subclavian artery and vein, divide brachial plexus under stretch

- release Lat dorsi & remaining soft tissues that bind shoulder girdle to anterior chest wall and allow limb to fall posteriorly and down 

- while holding arm across the chest divide posterior rotator cuff

- divide anterior and posterior muscles holding scapula to thoracic wall 

- trapezius / omohyoid / L scapulae / rhomboids / serratus anterior 

- suture pectoralis major and trapezius over lateral chest wall

- trim flaps and primary suture

 

Posterior Approach

 

Position

- lateral decubitus position near edge of operation table

 

Incisions

 

Posterior

- make posterior incision first

- begin at medial end of clavicle, extending laterally along clavicle over acromion process to posterior axillary fold

- along axillary border of scapula to a point inferior to scapular angle

- curve incision medially to end 5cm from midline of the back

- same incision as for anterior approach except posterior limb runs along axillary border of scapula

 

Anterior

- as above

- starts at mid 1/3 clavicle and runs inferiorly just lateral and parallel to deltopectoral groove

- then runs posteriorly through axilla to join posterior axillary incision at lower 1/3 of axillary border of scapula

 

Superficial Dissection

- elevate full-thickness skin flaps and subcutaneous tissue to medial border of scapula

- trapezius / lat dorsi divided parallel to medial border of scapula

- divide Levator scap / rhomboids / serratus anterior / omohyoid from scapula

- ligate vessels especially transverse Cervical artery and Transverse scapular artery

- free clavicle and divide at medial end with subclavius

- shoulder falls anteriorly

 

Deep dissection

- subclavian artery & vein / brachial plexus on stretch (divided close to spine)

- divide P major and minor & remove limb