Left First Toe Amputation (Ray, Cadaver)

Article Overview

Various systemic and local pathologies often necessitate first toe amputation, which aims to remove the diseased and dysfunctional portion of the limb while optimizing the functionality of the remaining limb and ensuring satisfactory wound healing.¹ The amputation should be performed at a level that is anatomically acceptable and minimizes the risk of future interventions.

Minor lower extremity amputations typically involve either toe or ray resections. The first ray is an essential component in the normal anatomy and biomechanics of the foot. By definition, the first ray consists of the hallux and the first metatarsal. The first metatarsal is the strongest and most important weight-bearing point in the forefoot, carrying roughly 40% of the body weight in standing position.² Loss of the first metatarsophalangeal (MTP) joint by amputation disrupts the integrity of the medial column and leads to disruption of lower extremity biomechanics involved in gait.

Ray resection, a surgical technique first described in the 1920s,³ is a viable treatment option for patients with various foot abnormalities. Indications for a ray resection include localized gangrene of the toe, infection of the toe with extension into the MTP joint, or osteomyelitis of the toe and/or metatarsal head. In cases of infection, it is necessary to take specimens from the tissue for testing. This allows for the identification of the specific infectious agent and the subsequent administration of targeted antibiotics. Each of these situations results in inadequate soft-tissue coverage of the defect following toe amputation, thereby leaving the metatarsal bone bare and avascular. Performing a partial metatarsal resection in conjunction with the toe amputation allows for sufficient soft-tissue coverage of the toe amputation site. It was found that resections of the first metatarsal performed from the MTP joint to the metatarsal neck are less likely to fail compared to resections of the first metatarsal proximal to the metatarsal neck. This could be due to the enhanced distribution of weight-bearing forces on the medial column when the length of the first metatarsal is preserved as much as possible.⁴ When performed properly, the surgery leaves a balanced, functional, slightly narrower forefoot that can be fitted properly into the shoe’s toebox.² The other major advantage of ray amputation over toe amputation is the cosmetic result.⁵

The surgical procedure discussed in this educational video is a left first toe ray amputation on a cadaver. The surgical procedure begins with the specimen positioned supine on the operating table with a pad placed beneath the ipsilateral buttock to control the physiologic external rotation of the lower limb. Most commonly, the procedure is performed under local anesthesia (i.e., ankle or popliteal block) and monitored sedation.⁶ The operation begins with marking the line for the incision, which will involve the proximal phalanx, and allow for the removal of the first metatarsal head. The incision line is marked in a circular shape at the base of the toe and then extended along the inner side of the foot. The incision is made using a scalpel, and care is taken to ensure that it is deep enough to reach the proximal phalanx and metatarsal head. The next step involves dissecting the tissues off the metatarsal head. This may involve removing tendinous tissue using a combination of blunt and sharp dissection. The initial debridement must be radical and include all obvious nonviable soft tissue to establish a viable, healthy, and well-perfused wound bed.

Once the metatarsal head is exposed, disarticulation is performed at the level of the proximal phalanx. Following the amputation, the next step is to create skin flaps along the metatarsal head. The use of sharp dissection and periosteal elevator can help create skin flaps and expose the metatarsal head and proximal phalanx without damaging surrounding structures. The skin flaps are created to provide adequate coverage over the exposed bone and facilitate closure. Once the skin flaps are created, part of the metatarsal head is cleared off to expose the cortex. The metatarsal bone is then transected clean. Enough bone must be removed so that flaps may be closed without tension. After the metatarsal head is removed, the joint capsule is cleared, and any remaining bone pieces are carefully removed. The space is then closed using interrupted sutures. Care is taken to ensure that the repair is tension-free and the flap is viable before closure.

Toe amputation is a significant predictor of future limb loss. Ray amputation appears to be preferred over finger amputation in selected cases. However, the literature does not provide precise indications on when to consider a ray over a toe amputation. The choice is therefore left to the operating surgeon, based on their clinical expertise and the patient’s conditions and expectations, taking into account the underlying pathology. This underscores the importance of choosing the correct technique and location for amputation to prevent or delay further interventions on the affected extremity.⁵