From the Guidelines
Chopart (transmetatarsal) amputation and below knee (transtibial) amputation are two distinct surgical procedures with different indications, outcomes, and effects on morbidity, mortality, and quality of life. The primary difference between the two procedures lies in the level of amputation and the resulting functional outcomes. Chopart amputation, as described in the WIfI system 1, is a midtarsal amputation that preserves the talus and calcaneus bones while removing the forefoot, making it suitable for patients with forefoot infections, gangrene, or trauma who have adequate blood supply to the hindfoot. This procedure maintains ankle motion and allows for better functional outcomes with less energy expenditure during walking compared to more proximal amputations. Some key points to consider when deciding between these procedures include:
- The patient's vascular status and extent of tissue damage
- The potential for wound healing and functional recovery
- The need for prosthetic support and rehabilitation In contrast, below knee amputation involves removing the leg below the knee joint, typically at 12-15 cm below the tibial plateau, and is indicated when there is inadequate blood supply to the foot, extensive infection, or trauma that cannot be managed with a more distal amputation. The choice between Chopart amputation and below knee amputation should be based on the patient's individual needs and circumstances, with the goal of preserving as much limb length and function as possible while minimizing morbidity and mortality. According to the WIfI system 1, Chopart amputation is suitable for patients with wound grade 2 or 3, where there is extensive tissue loss salvageable with a complex foot reconstruction or non-traditional transmetatarsal amputation. In terms of outcomes, Chopart amputation has been shown to result in better functional outcomes and less energy expenditure during walking compared to below knee amputation, although it may require additional procedures to balance the tendon and prevent equinus deformity. Overall, the decision between Chopart amputation and below knee amputation should be made on a case-by-case basis, taking into account the patient's vascular status, extent of tissue damage, functional goals, and comorbidities, with the goal of achieving the best possible outcome in terms of morbidity, mortality, and quality of life.
From the Research
Difference between Chopart and Below-Knee Amputation
- A Chopart amputation is a type of transmetatarsal amputation, which involves the removal of a part of the foot, specifically the forefoot 2.
- A below-knee amputation, also known as a transtibial amputation, involves the removal of the lower leg below the knee 3, 4, 5, 6.
Key Differences
- The level of amputation: Chopart amputation is a more distal amputation, whereas below-knee amputation is a more proximal amputation 2.
- Functional outcomes: Below-knee amputation is often associated with better functional outcomes, with 60% of patients able to ambulate again, compared to Chopart amputation, where only 44% of patients were able to successfully ambulate with a prosthesis 4, 2.
- Complications: Both types of amputations are associated with complications, such as wound healing problems and prosthetic fitting issues, but Chopart amputation may have a higher risk of postoperative wound complications 2.
Considerations
- Patient selection: The choice of amputation type depends on various factors, including the patient's baseline physical function, extent of infection, vascular patency, and comorbidities 2.
- Surgical technique: The type of incision used for below-knee amputation may not significantly affect the outcome, but a two-stage procedure may be beneficial in cases of wet gangrene 6.