Amputations

Otto-Bock

Ossur Rheo

Amputation ICD-10 Codes

Indications

• Traumatic amputation
• unrepairable vascular injury
• Mangled extremity
• Septic extremity
• Residual limb less functional than prosthesis
• Type III-C open tibial fractures with disruption of the tibial nerve or a crush injury with warm ischemia time > 6 hours.
• Widespread necrosis in medically unstable patient
• Severe open tibial fracture with crushed foot.
• Amputation predictors: mangled extremity severity score (MESS); NISSSA (nerve injury, ischemia, soft- tissue injury, skeletal injury, shock , age); Predictive Salvage Index (PSI); Limb Salvage Index (LSI). All have low sensitivity, high specificity and are not generally recommended as a criterion for amputation. (Bosse MJ, JBJS, 2001;83A:3).
• MESS score: six or less consistent with a salvageable limb. Seven or greater amputation generally the eventual result.

Considerations

• Amputation should be performed at the most distal level possible to improve ability to ambulate, decrease energy cost of walking and improve function.
• Pre-operative aids in determining amputation level: skin color, hair growth, and skin temperature, Transcutaneous oxygen tension (40 mmHg indicates good healing potential; if <40mmHg but >20mmHg consider elevating the extremity for 3 minutes, a decrease of >15mmHg indicates poor healing potential.
• Malnourished(serum albumin < 3.5 g/dl, total lymphocyte level < 1500cells/ml) or immunocompromised patients have markedly increased rates of perioperative complications.

Complications

• 69% phantom limb pain (Gallagher P Disabil Rehabil 2001;23:522)
• 42% residual limb pain
• 50% painful neuroma (consider gabapentin, pregabalin)

Post-Op Management

• 3 weeks: remove sutures, start shrinker sock
• 6 weeks: casting for socket/prosthesis fabrication
• 8 weeks: start therapy once patient is able to done prosthesis and stand for 15 minutes. 4-8 weeks of therapy.
• Consider gabapentin, pregabalin for limb pain / neuroma

Scapulothoracic / Forequarter Amputation

• Nerves: brachial plexus
• Vessels: subclavian artery and vein
• Concerns: Semi lateral postion, remove entire scapula, most of clavicle.

Shoulder Disarticulation

• Nerves: brachial plexus.
• Vessels: cephalic vein, brachial vessels/axillary artery, thoracoacromial artery
• Concerns: modified shoulder disartic with small portion of proximal humerus remaining is best (cut at surgical neck). Use deltoid myofasciocutaneous flap advanced distally to cover axilla. Reattach pec major and latissimus dorsi to humeral head, leave RTC intact.

Trans-Humeral (Above Elbow)

• Nerves:Median N, Radial N, Ulnar N
• Vessels: brachial artery, profunda brachii artery, cephalic vein, basilic vein
• Concerns: Equal anterior and posterior skin flaps. Length=1/2 the diameter of the arm. Generally utilize posterior triceps flap for distal bone coverage. Biceps and triceps are myodesed via bone tunnels. Level of bone section should be at lease 3.8cm proximal to the elbow joint to allow room for the elbow-lock mechanism of the prosthesis.

Elbow Disarticulation

• Nerves:ulnar nerve, median nerve, radial nerve
• Vessels: cephalic vein, brachial vein, brachial artery, basilic vein, radial recurrent artery and vein
• Concerns: anterior flap should extend just distal to the radial tuberosity. Posterior flap should extend 2.5cm distal to tip of olecranon. Suture ticeps the biceps and brachialis. Preserve 6cm of extensor muscle mass to suture into the medial epicondyle.

Trans-Radial (Below Elbow amputation, BEA, forearm amputation)

• Nerves: anterior interosseous N, superficial branch of radial nerve, posterior interosseous N, ulnar nerve, median N
• Vessels: anterior inteosseous artery, radial artery, ulnar artery, basilic vein, cephalic vein.
• Concerns: 4-5cm of proximal ulna needed. Equal anterior and posterior flaps. Length = slightly longer than 1/2 the forearm diameter. Consider creating an anterior flap of flexor digitorum sublimis sutured into the deep dorsal fascia. Never use the entire anterior muscle mass.

Wrist Disarticulation

• Nerves:Ulnar nerve, Median Nerve, Superficial branch of radial nerve, dorsal branch of nerve
• Vessels: radial artery, unlar artery
• Concerns: preserving the distal radioulnar joint preserves suppination and pronation ability. Fish mouth incision with larger palmar flap. Allow resected tendons to retract into forearm. Countour radial and ulnar styoids to smooth surface.

Hip Disarticulation

• Nerves: femoral nerve,
• Vessels: femoral artery and vein
• Concerns: posterior flap with raquet-shaped incision.

Trans-Femoral Amputations (above knee, AKA)

• Nerves/Vessels: (1)deep femoral artery / 2 veins (2)Sciatic nerve follow branches up to it:tibial nerve, peroneal nerve, sural nerve ?obturator nerve, great saphenous vein, superficial femoral artery / vein?
• Concerns: preserve adductors and abductors for balance;
• Equal anterior and posterior flaps with lengths = 1/2 diameter of the limb +1cm
• Ideal Stump length: preserve 50%-50% of femoral length. Leaving less than 2 inches of femur functions as hip disarticulation, but with complicated prosthesis fitting. At least 3 inches of femur must be removed for socket, adaptors and connections to the prosthetic knee. If less than 2 inches of femur remaining consider hip disarticulation.
• ASEC technique and video.

Knee Disarticulation

• Nerves/Vessels: (1)saphenous N & greater saphenous vein (2) tibial N, popliteal artery and vein (3) common peroneal N (4) sural N, small saphenous vein.
• Concerns: Retain gastroc and cruciates. Generally posterior flap, can do sagittal flaps.
• Posterior flap length = diameter of the leg at the femoral condyles + 1cm.
• Best option for non-ambulatory patients. Transtibial amputation has increased risk of wound problems and knee flexion contractures. Transfemoral amputation has shorter lever arm which decreases bed mobility, transfer ability and sitting stability.
• Descreased walking energy expenditure compared to transfemoral amputation. better thigh muscle balance, increased prosthesis stability. Fewer knee-joint prosthetic components, poor cosmesis compared to transfemoral prosthesis.
• ASEC technique and video.
• (Bowker JH, JBJS 2000;82A:1571), (Mazet R JR, JBJS 1966;48A:126)

Trans-Tibial Amputations (below knee, BKA)

• Nerves: tibial N, saphenous N, sural N, deep peroneal N
• Vessels: Posterior tibial artery and vein, great saphenous vein, small saphenous vein, anterior tibial artery
• Concerns: Fibula should be 1-2cm shorter than tibia, suture gastroc/soleus to anterior tibia. Posterior flap lenght = diameter + 1cm. Do not amputate in distal 1/3 (no suitable flap coverage).
• Ideal Length: amputation at the junction of the proximal 1/3 and middle 1/3 of the tibia.
• ASEC technique and video.
• • Avoid amputation in the distal 1/3 to 1/4 of the tibia, as there is very little muscular tissue for padding in the distal most portion of the lower limb.
  • ideally the tibia is divided at a point where the distal edge posterior flap occurs at the junction of the soleus muscle and the Achilles tendon.
  • Distance between the ground and the end of the residual limb should be 8 to 10 inches for the use of most integrated high-impact foot/pylon/shock absorbing systems.
  • tibial bone cut is planned to keep one third to one half of the length of the tibia.
  • Measure the anterior to posterior diameter of the limb, at the level of the tibial bone cut.Add one cm.
  • Draw Incisions: medial and lateral extensions are straight distal, and do not drift posteriorly. The length of the extensions is equal to the AP diameter of the limb at the proposed level of the tibial bone cut, plus one additional cm.
  • Anterior incision – down approx half diameter of limb. Medially this extends down to an inflection at the edge of gastrocnemius muscle. Laterally, this extends down to the posterior edge of fibula. The incisions curve very slightly from distal to proximal as it moves from anterior to posterior.
  • Posterior incision is drawn straight around the back of the leg, connecting the ends of the medial and lateral incisions.
  • Esanguinate leg inflate tourniquet.
  • Incisions
  • saphenous vein & nerve, the nerve is lateral to the vein.
  • Superficial Peroneal Nerve: lateral compartment, Proximally, it is found between the peroneus longus and peroneus brevis muscle. Distally, may change from the lateral to the anterior compartment.
  • Transect Anterior and Lateral Compartment Muscles:
  • Disect down lateral edge of tibia and along the syndesmotic membrane over to the fibula. Pass the clamp under the anterior and lateral compartment muscles. Transect the muscles.
  • Anterior compartment: Anterior Tibialis (AT), Extensor Hallucis Longus (EHL), and Extensor Digitorum Longus (EDL): muscles are transected at the level of the tibial bone cut.
  • Anterior tibial vessels and the deep peroneal nerve are located just anterior to the syndesmotic membrane. Dissect the anterior tibial vessels, clamp them, and double ligate first with a stick tie, then with a free tie (proximal to first tie).
  • Lateral Compartment: Peroneus Longus (PL) and Peroneal Brevis (PB). transect at the level of the tibial bone cut.
  • Cut tibia,  shape with an anterior bevel to better accommodate prosthetic fitting.
  • Cut Fibula  1 and 2 cm proximal to the level of the divided tibia
  • shaped to smooth the anterior corner, the outer or lateral edge.
  • Dissect down the back of the tibia and fibula and remove the foot, the deep posterior compartment is carefully lifted off of the soleus. Care is taken to keep the muscular investing fascia with the soleus.
  • Tie small perforating vessels that go from the posterior tibial and peroneal vessels down into the soleus,
  • Tibial Nerve and Posterior Tibial Vessels: Posterior tibial Vessels are located within the fascia of the deep posterior muscle compartment.
  • Isolate the posterior tibial vessels, clamp and cut, Double Ligate.
  • Pull the tibial nerve distally and transect.
  • Isolate Peroneal Vessels within the deep posterior muscle compartment, lateral to the posterior tibial vessels, and are between the FHL muscle and the PT muscle, very close to the deep edge of the fibula. Double Ligate.
  • PT, FHL, and FDL are transected at or just distal to the level of the tibial bone cut.
  • Locate Small Saphenous Vein and Sural Nerve: Sural nerve located between the skin and the superficial fascia. just lateral to the small saphenous vein. Shorten sural nerve well proximally.
  • Let the tourniquet down.
  • Hemostasis / Bone Wax:
  • Irrigate
  • Myodesis of the Fascia / Achilles: suture superficial  posterior compartment musculature into the periosteum of the tibia (or via drill holes in the tibia) and to the fascia of the anterior compartment with absorbable 1 or O suture
  • Subcutaneous Tissue Closure: absorbable 2-O suture.
  • Nylon Skin Sutures:
  • Mastisol, steri-strips
  • Zerofrom, 4x4s
  • amputation sock.
  • reticulated foam end-pad.
  • Webril
  • Plaster cast in 3-5 degrees of flexion, Supra-condylar Mold

  Hindfoot Amputations

  • Nerves:
  • Vessels:
  • Concerns:
  • Syme's: Syme's socket has bulky appearance, generally must have lifts applied to contralateral shoes. Risk of migration of the distal fatty heal pad (posteromedially)
  • Chopart - Saves Talus and Calcaneus
  • Boyd - Talectomy + Calcaneal / Tibial Fusion with forward translation of calcaneus (children)
  • Pirgoff - Talectomy + Calcaneal / Tibial Fusion with forward rotation of calcaneus (children)
  • ASEC Partial Calcanectomy technique and video.

  Midfoot Amputations (transmetatarsal / LisFranc)

  • Nerves:
  • Vessels:
  • Concerns: Consider First MT/cuneifrom disarticulation with TM amp at base of 2-5 (preserves peroneus brevis), Consider Achilles tendon lengthening. Cast post-op to prevent equinus
  • ASEC technique and video.

  MTP Joint Disarticlation

  • Nerves: digital N
  • Vessels: digital arteries and veins
  • Concerns: leave cartilage intact

  Foot Ray Amputation

  • Nerves:digital N
  • Vessels: digital arteries and veins
  • Concerns: may include some or all of corresponding metatarsal. Isolated 2-5 ray amputatios generally due well. 1st ray amputations lead to second MT head overload, difficult orthosis care.

  References

  • Smith DG, Atlas of Amputations and Limb Deficiencies, 2004, ISBN:9780892033133
  • www.ampsurg.org
  • Upper Limb Cross Sections
  • Lower Limb Cross Sections
  • Pelvis/Thigh Cross Section
  • Anatomy Atlas