etiology and surgical amputation

total amputations in US in 2019

564,893, mostly LE

most likely cause of amputation

vascular disease, including diabetes, trauma, cancer, and congenital

reasons for amputation

• frequently elective

• occasionally emergent

immediate post op care

• prevention of infection

• prevention of DVT

• promotion of wound healing

• reduction of edema

• prevention of contraction

management of

• not really weightbearing up to 6 weeks

• antibiotics

post op complications

• mortality

• infection

• thrombus

• delayed wound healing

• inadequate soft tissue coverage/inadequate skin condition

• chronic pain

• contracture

• heterotrophic ossification

• re-amputate

mortality

• immediate perioperative mortality is increased

• those with major and comorbidities have a higher morbidity

when frequently elective surgery for amputation

• failed re-vascularization

• failed limb salvage in trauma

• chronic progressive infection; osteomyelitis, wet or gas gangrene

• unstable Charcot foot

• cancer treatment

what increases risk of phantom pain

pain prior to amputation

occasionally emergent

• trauma

• critical limb ischemia

  • vascular disease

  • thrombus

  • trauma

  • medical trauma: Vasopressor induced acute limb ischemia

• infection

  • wet gangrene

  • gas gangrene

  • aggressive super bug

goal of amputation

1. healing of the residual limb

2. maintain as much length as possible

why is maintaining length important

length is critical for functional outcomes

indications for amputation

• critical limb ischemia

• acute arterial thrombosis or htromboebolism

• truama resulting in a mangked extremetiy or failed attempt at limb salvage

• severe infections with extensive soft tissue or bony destruction, or osteomyelitis

• locally unresectable malignant tumors of the musculoskeletal system

• frostbite-related gangrene

• failed management of acute compartment syndrome

• failed management of Charcot’s degenerative osteoarthropathy

pre-surgical intervention

• amputation care is at every time frame best provided in a coordinated multidisclipanary team; leader is surgeon

key components of pre-surgical care

• level selection

• nutrition assessment

• psychologic support

• education and empowerment of the family

pre-op management of nutriional

• calorie intake

  • increased caloreie demand for wound healing

  • 25-30 cal/kg increase for ulcer healing

  • calorie intake stops for 24 hours collagen syntheisis stops

• serum albumin

  • biochemical assessment of nutrional staus normal 3.5-5.0

  • pre-albumin is better indicator of short-term dietary intake

nutrition

• protein levels: building blocks for many of the chemical and cells

• vitamin c: responsible for collagen

• zinc promotes epitheliazation and cellular proliferation

risk factors for psychiatric issues

• young age at time of the amputation

• pain

• premorbid neurotic personalty lifestyle

• poor coping skills

education and empowerment of the patient and family

• surgical procedure

• rehab process

• prosthetic deivces

• peer support and counseling

• amputaiton coalition of America

minor

foot and partial foot amputation

foot

• toe amputation

• metatersal ray resection

what requires shoe modification

• transmetatrsal amputation, might need a shoe fill

• Lisfranc or Midfoot amputation

  • disarticulation of all the metatarsals

• Chopart or midtarsal disarticulation

  • calcaneus and talus remain

major

ankle and up

• TTA: from tibial tubercle to malleolus

• Symes: ankle disarticulation

• hemipelvectomy

• hip disarticulation

• transfemoral amputation TFA: greater trochanter to femoral condyles

• knee disarticulation

level selection

• length matters

• length of both the entire limb and the sengment within each level have critical consequencse

consequences

• mortality rates: higher in advancing levels of amputaiton

• healing rates lower in distal levels

• energy expenditure is less with longer limbs

• joint function is maintains with longer limbs

• functional mobility is higher and rejection rates lower with lower levels of amputation

• insertion of distal muscle groups are maintained

• weight distribution is greater with longer limb - better comfort

• suspension - easier to hold the leg on longer residual limbs

• componentry

how do surgeons decide

no standard, depends on surgeon and situation as well as the cause of amputation

PAD and amputation

• leading cause

• concomitant central artery disease

factors that predict need for amputation in people with critical limb ischemia

• tissue loss

• end stage renal disease

• poor functional status

• diabetes melitus

diabete metiltus

• 10 fold increase in amputation risk

• have amputation at earlier age

• more disability

• progress to higher levels or to other limb

• die at younger age

critical limb

• salvage vs. amputation

• contra-indication to limb salvage

  • poor functional limb

  • extensive necrosis

  • life threatening toxemia

  • absolute absence of distal vessels

  • revascularization not advised due to seevere comorbidity

recommendations in persons w/ symptoms of limb iscehmia

• clinical exam

• combined with objective vascular testing

clinical exam

level selction based on exam only

• 80% healing in transtibial

• 90% healing in transfemoral

vascular tests

• angiography

• ankle toe pressure

• transcutaneous oxygen measurement

• skin perfusion pressure

• low sensitivty for prediction wound

amp for trauma

• salvage vs amp

• western trauma asociation critical decisions in trauma

western trauma association critical decisions in trauma

• not well established

• hemodynamic stability first: priority trunk/central trauma to extremity

• extremity

  • re-align anatomic position and classify fracture

  • re-establish vascular

  • assess nerve involvement

key concepts

• fracture of soft tissue: severity of tissue iinjury had greatest correlation w/ amp vs. bone involvement

• injury zone

• heroic measures to preserve the knee

• typical stage amputation

salvages

• those with salvage have higher rates of complication, longer duration and more secondary hospitalization, functional outcomes the same

assessment of infection

• systemic infection

• clincal infection signs

systemc infection

• fever, fatigue, malaise

• diabetics

  • hyperglycemia, malaise

  • absent fever

clinical infection signs

• drainage (purulent, foul smell), cellulitis, edema, sinus tracts, deep abscess

• probe to bone (osteomyelitis)

• CBC and ESR

• CRP

• osteomyelitis

• gangrene: wet (infected) vs. dry (necrotic)

infections that leads to amputation in “healthy” patients

• meningocacal mengitis

• speitcemia

• staphyloccoccus

• MRSA

• necrotzitis fascitis

malginancy

• 7.1 new cases per 100.000 per year

• limb salvage surgery is primary tratment and standard of care

• rate of amputation is low and decreasing

types of tumers treated with amp

osteosarcomas and chrondosarcomas

• level selection based on clean borders and dictated by biopsy

principles of surgery

• management of musculture

• tendons

musculature

• myofascial closure: loose approximation of fascial tissue

• myoplasty: muscles from opposing groups are attached to each other

• myodesis: muscle is attached to the distal bone

tendons

• tendonisis is possible in certain levels of amp when the muscle tendins is maintaines

• provieds best stabilization of the muscle and allows direct suturing tot eh bone

muscle tension

tension and appropriate length is critical to stabilize joints

too much tension

• pain

• failure of suture fixation

• proximal contracture in 2 joints

too little tension

muscle weakness and inability to stabilize joint

nerves

• all transected nerves will form a neuroma and neuromas can by symptomatic; no intervention for neuroma pain is definitive

• concensus

  • place a small amount of tension on the nerve and do sharp transection

  • allow it to “bounce back” into soft tissue

• care should be given no to be overzealous with tension

toe amp

• generally, at the MTP joint

• no shoe mod

  • extra, wide, extra depth

• custom triaminat insert

outcomes for toe

• healing rates: 25% future amp

• functional outcomes: normal walking w/o deviation

• insole mod

concerns for toe amp

abnormal foot pressures

• smaller surface area

• long term viability to insensate foot

transmetatarsal surgery

• cascade of length w/ 1st ray longest and 5th ray shortest

• plantar bevel of the bone to reduce distal pressure

prostehtic interventions for TMA

• trasnmetatrsal amp

  • susceptible to PF contracture

  • toe fillers

  • high top shoes

partial

chopart and lisfranc prosthetics

must provide anterior stability

• slipper prostheis

• carbon inerts

• AFO w/ toe filers

syme indications

• sever deformed or crushed forefoot

• gangrene past the transmetatarsal level but not past mid tarsals

• with vascular disease only if vascularity proximity

contraindications of symes

• compromise to the heel pad

• callutos or gangrene that has advances proximally

• poor vascularity proximal to ankle

symes outcomes compared to transtibial

• end bearing is possible

• energy expenditure w/ presthetic

contradindications of TTA

• gangrene within 4-5cm of tibial tubercle

• knee flexion contracture greater than 70 degrees

TTA surgical techniques

• posterior flap

• long posterior flap

• skew flap

• Ertl procedure

advantages of knee disarticulation

• longest lever arm

• maintains adductor insertions

• maintains intact growth plate for children

• allows distal end bearing

disadvatages of knee disarticulation

• technically difficult

• cosmesis

• limitation in knee compenetry and suspension

TFA surgery

uses fishmouth incision

normal alighnment of the femur

• position of the femur in adduction (10-15 degrees)

• angle of inclination of the femur proximally

• medial condyle of the femur extends further distally than lateral condyle

alignment with TFA

• loss of adductor strength

• femur starts migrating laterally

• abduction contracture, can’t stabilize the pelvis

most important group to strengthen in TFA for knee stability

hip extensors