Amputations- Dr Ntoloko.pptx

Amputations S Ntloko  Outline Indications Principles of amputation surgery Amputation types Complications  Introduction Despite major advances in revascularisation, lower extremity amputation remains a common procedure in modern vas...

Amputations S Ntloko  Outline Indications Principles of amputation surgery Amputation types Complications  Introduction Despite major advances in revascularisation, lower extremity amputation remains a common procedure in modern vascular practice PVD alone or with Diabetes account for >50% - Incidence = 12-50 per 100 000 / year acc to TASC II working group - Trauma is the 2nd leading cause Although often viewed as a failure of treatment, major amputation should be embraced as an important, definitive treatment option. 50-75% of amputees die within 5 years Basic anatomy  Basic anatomy Forefoot: 5 toes + metatarsals Midfoot: arches of the foot ie. tarsal bones Hind foot: heel + ankle  Indications Elective ( MDT decision with the Emergency ( life saving  patient) decision based on the medical need) Peripheral arterial disease Complications of diabetes Trauma mellitus Failed limb salvage Failed minor amputation NB: do not amputate in an ischaemic limb prior to revascularization  Classification Minor (below the ankle) Toe Transmetatarsal Major (above the ankle) Below knee amputation – BKA Through knee amputation – TKA Above knee amputation – AKA Hip disarticulation  Types of amputation Guillotine Formal  Staged Amputations Local study Important for diabetics Advantage – healing improved Disadvantage – 2 operations in high risk patients Single operation – up to 30% will require revision amputation Y Desai, JV Robbs, JP Keenan: Staged below knee amputations for septic peripheral lesions due to ischaemia. Br J Surg. 1986  Definitions Toe amputation: Involves division of the phalynx or disarticulation of the metatarsal-phalangeal joint Ray amputation: Removal of the corresponding metatarsal Transmetatarsal amputation: partial foot amputation through the metatarsals  Principles GENERAL Remove all infected, gangrenous, ischaemic tissue Preserve length Wound that heals successfully - leaving a functional limb Avoid - repeated amputations - “Funny feet” - Non healing operative sites  Principles of amputations TECHNICAL Fashion adequate flaps Bone divided proximal to muscle Bevel bone Myoplasty Haemostasis Atraumatic skin approximation Toe amputation principles Conserve function and as much tissue as possible Partial amputation of a toe keeps the adjacent toes in normal alignment The head of the 1st metatarsal (hallux) is important in weight bearing and every effort must be made to spare it Amputation through a phalange is better than disarticulation Preserving the tendon attachments at the base of the phalynx Toe amputation Toe amputation: skin incisions  Toe amputation: physics The hallux is important for balance and walking because without it we are unable to push-off The 2nd toe acts as a lateral support for the hallux therefore its amputation may lead to hallux valgus The transverse arch gets affected with any toe amputation Toe amputations: Post op Weight bearing is prohibited if a formal amputation is performed until wound healing has been achieved  Mid and Hindfoot amputations Lis Franc Chopart Symes Advantage: preservation of length and epiphyseal plate in children Disadvantages: wound breakdown cosmesis Complications: equinous deformity Due to imbalance in gastroc-soleus and dorsiflexion  Below knee amputation Should be scar free Below knee stump weight bearing: - Tibial tuberosity - Lateral aspect of tibia - Anterior aspect tibia  Ideal BKA stump The ideal BKA stump should be: - 1/3 the length of the tibia - The fibula should be cut higher as it is prone to diastasis and erosion through the skin - There should be no flexion contractures - The nerves should be divided under tension to avoid neuroma in scar tissue  Energy expenditure Amputation level Energy above baseline % Long transtibial (BKA) 10 Average transtibial 25 (BKA) Short transtibial 40 Bilateral transtibial 41 Transfemoral (AKA) 65 Wheelchair 0-8  Wound healing Failure to heal amputation is multifactorial Causes - Ischaemia - Infection - Haematoma - Trauma  Predictors of wound healing Emphasis - assessing blood flow at level of amputation - predict wound healing No single test – 100% accuracy Better at predicting wound healing than failure Utilizing one test alone – unnecessary proximal amputation  TcPO2 Importance of optimising level selection TcPO2 demonstrated to be most accurate predictor of wound healing Applies to both major and forefoot amputations Several advantages: - ease of measurement - Reproducibility - simple instrumentation Malone et al: Prospective comparison of non-invasive techniques for amputation selection level. Am J Surg 154:179-184, 1987  Antibiotics Prophylactic antibiotics - broad spectrum aerobic cover - perineal organisms - Gram positive organisms (Staph) Significant decrease in infection rate  Soft Dressings Advantages Ease of application Low cost Wound is accessible Disadvantages Decreased skin perfusion Knee contracture Poor pan control Decreased mobility Complications Neuroma Avoid by cutting nerve sharply Under tension  Rehabilitation Phase 1 - avoid contractures - Physiotherapy – passive movements and isometric - Exercises  Rehabilitation Phase 2 - Standing and balancing exercises - parallel bars and inflatable prosthetics - Endurance exercises may be needed  Conclusion Earlier appropriate referral Amputation as a therapeutic option Consider co morbidities of patients Selecting appropriate level Objective tests Team approach