High-yield overview
Toe to Ankle Disarticulation
Preserve lengthvs ensure healing
EquinovarusRisk in proximal partial-foot
Heel padKey to a durable Syme
Similar QoLPartial foot vs transtibial
Levels (distal → proximal)
Toe / Ray
PatternSingle toe or toe + metatarsal. Well tolerated; first-ray loss most affects push-off.
Treatment
Transmetatarsal (TMA)
PatternAcross the metatarsals. Good function; balance with tendo-Achilles lengthening if equinus.
Treatment
Lisfranc / Chopart
PatternTarsometatarsal (Lisfranc) / midtarsal (Chopart) disarticulation. Strong equinovarus tendency - rebalance.
Treatment
Syme / Pirogoff-Boyd
PatternAnkle disarticulation (Syme) preserving the heel pad / calcaneo-tibial fusion (Pirogoff/Boyd) for end-bearing.
Treatment
Critical Must-Knows
- Partial foot amputation levels from distal to proximal: toe, ray, transmetatarsal (TMA), Lisfranc (tarsometatarsal), Chopart (midtarsal), then ankle disarticulation (Syme) and the calcaneo-tibial Pirogoff/Boyd.
- The principle is to preserve as much functional, durably-healing, end-bearing length as possible.
- Proximal partial-foot amputations (Chopart, and to a lesser extent Lisfranc) lose the dorsiflexors and everters, creating a strong EQUINOVARUS deformity that must be rebalanced (tendo-Achilles lengthening +/- tibialis anterior tendon transfer).
- A Syme amputation depends on a viable, well-anchored HEEL PAD for an end-bearing stump.
- Healing is the dominant concern in dysvascular/diabetic feet; partial foot amputation has high rates of delayed healing and ipsilateral reamputation.
- Compared with transtibial amputation, partial foot amputation has similar quality of life and mobility, while transtibial carries higher mortality (reflecting sicker patients).
Clinical Pearls
- “Chopart amputation classically drifts into equinovarus - plan rebalancing (Achilles lengthening, TA transfer) at the time of surgery.
- “A durable Syme needs the heel pad securely anchored under the tibia and a patent posterior tibial artery.
- “Reamputation is common after partial foot amputation in the dysvascular/diabetic foot - counsel accordingly.
The Muscle-Balance Trap
Why proximal levels deform
As the amputation moves proximally (Lisfranc → Chopart), the dorsiflexor (tibialis anterior, long extensors) and everter (peroneal) insertions are lost, leaving the intact triceps surae and tibialis posterior unopposed. The result is a powerful equinovarus deformity that ulcerates the stump if not corrected.
The fix
Rebalance at the index operation: tendo-Achilles lengthening (to counter equinus) and, for Chopart, tibialis anterior tendon transfer to the talus/midfoot (to restore dorsiflexion). Failure to rebalance is the classic reason a Chopart amputation fails.
The Levels
Forefoot Levels
- Toe amputation: for isolated digital gangrene/osteomyelitis; well tolerated. Loss of the great toe most affects push-off and balance.
- Ray amputation: toe + its metatarsal (e.g. for deep infection tracking up a ray). Border rays (1st, 5th) tolerate ray resection well; central rays narrow the foot.
- Transmetatarsal amputation (TMA): division across all metatarsals (ideally leaving a slightly longer first metatarsal). Good functional level; preserve a robust plantar flap and lengthen the Achilles if there is equinus to prevent forefoot pressure on the stump.
Principles & Decision-Making
Length vs Healing vs Balance
Three competing goals govern level selection: preserve functional length (better gait, less energy cost, end-bearing), ensure the wound heals (vascular supply, infection control, soft-tissue coverage), and maintain muscle balance (avoid equinovarus). The most distal level that will reliably heal and stay balanced is usually best.
- Healing assessment: vascular status (pulses, ankle-brachial/toe pressures, transcutaneous oxygen), nutritional and glycaemic optimisation, and infection control are decisive in the dysvascular/diabetic foot.
- Soft tissue: a durable, sensate, well-vascularised plantar/heel flap is the goal; the plantar skin is the ideal weight-bearing surface.
- Balance: plan tendon rebalancing (Achilles lengthening, tibialis anterior transfer) for proximal partial-foot levels.
- The partial-foot vs transtibial decision: when a partial foot amputation is unlikely to heal or remain functional, a transtibial amputation with a good prosthesis may give better, more predictable function - a genuine shared decision.
Mnemonic
TRTLCSPartial Foot Levels (distal → proximal)
T
Toe
Digital amputation.
R
Ray
Toe + metatarsal.
T
Transmetatarsal
Across the metatarsals (TMA).
L
Lisfranc
Tarsometatarsal disarticulation.
C
Chopart
Midtarsal disarticulation (equinovarus risk).
S
Syme
Ankle disarticulation (heel pad, end-bearing).
Hook:Toe, Ray, TMA, Lisfranc, Chopart, Syme - more proximal = more equinovarus.
Evidence Base
Evidence
Outcomes of Partial Foot vs Transtibial Amputation
Dillon MP, Quigley M, Fatone S • Syst Rev (2017)
Key Findings:
- Systematic review of 29 studies on dysvascular partial foot amputation (PFA) versus transtibial amputation (TTA)
- A large proportion of PFA patients experience delayed wound healing and ipsilateral reamputation
- TTA carries higher mortality than PFA - likely reflecting more advanced systemic disease in TTA candidates
- Mobility and quality of life may be similar between PFA and TTA
Clinical implication: Informs the partial-foot-versus-transtibial decision: PFA preserves the limb but risks reamputation; the level choice is a genuine shared decision.
Evidence
Quality of Life: Partial Foot vs Transtibial
Quigley M, Dillon MP • Prosthet Orthot Int (2014)
Key Findings:
- Systematic review comparing quality of life in partial foot versus transtibial amputation
- Available evidence suggests quality of life may be similar between the two levels
- Small differences are unlikely to be clinically meaningful
- Evidence is limited - level decisions should be individualised
Clinical implication: Quality of life alone does not strongly favour preserving a partial foot over a transtibial amputation - heal-ability and function should drive the level.
Viva Scenarios
Practise clinical reasoning and management decisions out loud
Viva scenarioStandard
Scenario 1: The failing Chopart amputation
Clinical prompt
“A patient who had a Chopart amputation returns with an ulcer over the front of the stump and the foot pointing down and in. What has happened and how is it prevented/treated?”
Practical approach
The stump has developed an equinovarus deformity, the classic complication of a Chopart amputation. At the midtarsal level the insertions of the dorsiflexors (tibialis anterior, long extensors) and the everters (peroneals) are lost, leaving the triceps surae and tibialis posterior unopposed, so the residual talus-calcaneus segment is pulled into equinus and varus, and the prominent distal stump ulcerates. It is prevented by rebalancing at the index operation - tendo-Achilles lengthening to correct equinus and a tibialis anterior tendon transfer to restore dorsiflexion. For the established deformity I would offload and treat the ulcer, then correct the deformity surgically (Achilles lengthening and tendon transfer/rebalancing); if the foot cannot be made plantigrade and ulcer-free, conversion to a more proximal level (e.g. Syme or transtibial) may be needed. This case illustrates why proximal partial-foot amputations must be balanced, not just resected.
Key clinical points
Recognise equinovarus as the Chopart complication
Mechanism: lost dorsiflexors/everters, unopposed triceps surae/tibialis posterior
Prevent with Achilles lengthening + tibialis anterior transfer at index surgery
Salvage: rebalance/offload, or convert to a more proximal level
Common pitfalls
Performing a Chopart amputation without rebalancing
Treating only the ulcer and ignoring the deforming force
Further questions
“What does a Syme amputation depend on?”
“A viable, securely-anchored heel pad under the distal tibia (and an adequate posterior tibial artery) for an end-bearing stump.”
Guidelines, Registries & Global Practice
Global Practice Picture
Partial foot amputation is performed worldwide, most often for the dysvascular/diabetic foot. The internationally consistent principles are: choose the most distal level that will reliably heal and stay balanced; rebalance proximal partial-foot levels to prevent equinovarus; secure a durable plantar/heel weight-bearing surface; and frame the partial-foot-versus-transtibial choice as a shared decision based on heal-ability and function.
Side-by-Side Synthesis
Toe / Ray
- Joint/bone
- Digit / metatarsal
- Key issue
- Great-toe loss affects push-off
Transmetatarsal
- Joint/bone
- Across metatarsals
- Key issue
- Achilles lengthening for equinus
Lisfranc
- Joint/bone
- Tarsometatarsal
- Key issue
- Early equinovarus tendency
Chopart
- Joint/bone
- Midtarsal
- Key issue
- Strong equinovarus - rebalance (Achilles + TA transfer)
Syme
- Joint/bone
- Ankle disarticulation
- Key issue
- Heel pad-dependent, end-bearing
Pirogoff / Boyd
- Joint/bone
- Calcaneo-tibial fusion
- Key issue
- Durable end-bearing stump
Exam day cheat sheet
Levels (distal → proximal)
- Toe / Ray
- Transmetatarsal (TMA)
- Lisfranc (tarsometatarsal)
- Chopart (midtarsal); Syme (ankle); Pirogoff/Boyd
Principles
- Most distal level that heals + stays balanced
- Proximal levels → equinovarus (rebalance)
- Achilles lengthening + tibialis anterior transfer
- Durable plantar/heel weight-bearing surface
Decision
- Healing dominant in dysvascular/diabetic foot
- PFA: high reamputation; TTA: higher mortality (sicker)
- QoL/mobility similar PFA vs TTA
- Shared decision on level