Chapter 112 - Lower extremity amputation operation Flashcards
The first use of tourniquet for amputation
1674 Morell (France) in battle of Besancon
Use of antiseptic for amputation
1867 Lister prior to this 50% died from infection
General principles of amputation surgery
1) atraumatic tissue handling 2) excise all nonviable/infected tissue 3) tourniquet for blood loss 4) eliminate sharp bone edge/fragments 5) minimize number of cuts 6) sharp transect nerve allow retraction 7) minimize cautery 8) tension free closure 9) myodesis/myoplasty to stabilize antagonistic muscle group 10) drain to reduce dead space
Myoplasty in amputation
Suture fixation of antagonistic muscle group
Myodesis in amputation
Direct suturing of musculotendinous unit to bone
Ring sequestra
Devitalized area of bone from excessive periosteal stripping
bones of the ankle
1) 7 tarsal bone 2) 5 metatarsal bone 3) D1 has two phalanges 4) others have 3 5) medial + lateral sesamoid bone in flexor of D1 provides stability 6) joint capsules are around interphalangeal and metatarsophalangeal hinge joints 7) ligamentous and tendinous attachment work with planta fascia for integrity
Bone anatomy of the foot and ankle
FIGURE 112.1
Ray amputation
digit amputation + metatarsal head amputation
Risk of ulceration in D1 ray amputation
60%
Lisfranc joint
Tarsometatarsal joint joins the midfoot and forefoot
Stability of metatarsal maintained by
1) deep transverse metatarsal ligament distally 2) plantar ligament distally 3) plantar metatarsal ligaments proximally 4) articulate with 3 cuneiform bones (D1-3) and cuboid laterally (D4-5)
TMA key points
1) metatarsal cut each 3mm shorter than the last from D1 to D5 2) 30-45 degree plantar bevel helps with ambulation 3) Achilles tendon lengthening or transection? - avoid risk of recurrent ulceration
Proximal/hind foot amputations
Lisfrank tarsometatarsal Chopart midfoot Syme Boyd Pirogoff
Talocrural joint
Talus with tibia and fibula Supported by 1) deltoid ligament 2) anterior and posterior talofibular ligament 3) calcaneofibular ligament
Subtalar joint
talus with calcaneus Supported by 1) medial and lateral talocalcaneal ligament 2) cervical ligament
Talocalcaneonavicular joint
multiaxial joint supported by 1) talonavicular ligament 2) plantar calcaneonavicular ligament
Supination of ankle
Inversion Produced by tibialis anterior and posterior
Pronation of ankle
eversion Produced by peroneus longus and brevis
Lisfranc amputation first described in
1815 Lisfranc
Lisfranc steps
1) release tendon and synovial sheaths at level of skin incision 2) 1, 3, 4, 5 tarsometatarsal joints disarticulated 3) 2nd metatarsal dividied 1-2 cm distal to medial cuneiform 4) modified* preserve base of 5th metatarsal for peroneus brevis insertion 5) Achilles tendon release transection/Z-plasty 6) plantar fascia approximated to dorsal periosteum
Chopart amputation first described in
1814 Chopart
Chopart steps
1) incision through talocalcaneonavicular joint and calcaneocuboid joint 2) achilles tenectomy 3) extensor hallucis longus and tibialis anterior tendon reattached to talar neck 4) extensor digitorum longus attached to calcaneus
Post op key points for lisfranc and chopart amputation
1) short leg plaster cast molded to ensure talus dorsiflexed in relation to tibia 2) ensure calcaneal tuberosity is parallel to long axis of tibia 3) weight bearing in 6 weeks 4) lisfrank will need toe filler 5) chopart will need custom ankle-foot orthosis and filler
Syme amputation first described in
1843 Syme
Syme steps
1) anterior incision across ankle distal to top of malleoli 2) posterio incision extends from malleoli vertically down and across sole of foot 3) extensor tendon divided at level of skin 4) dorsalis pedis artery ligated and divided 5) ankle joint capsule incised while plantar flexing the foot before dividing medial and lateral ankle ligaments 6) transect posterior tibialis and flexor hallucis longus 7) avoid injury to posterior tibial nerve 8) heel fat pat dissected carefully but stay close to calcaneus to avoid buttonhole 9) disarticulate ankle 10) malleoli divided at level of articular surface of tibia and reduce width 11) drill holes in medial, anterior and lateral part of distal tibia and fibula to secure heel pad under tibia
Two stage syme difference
1) wound closed by suturing heel flap to dorsal fascia 2) 6 weeks later malleoli removed through separate vertical incision
Syme amputation key considerations
1) preserve limb length 2) leg-length discrepancy 3) cosmetically not as appearling