Foot deformities in a context of leprosy.
African woman admitted to hospital for foot deformity and skin lesions made of erythema nodosum. She has previously been treated for leprosy in her childhood.
Leprosy is an infectious disease caused by Mycobacterium leprae ( Hansen’s bacillus). It is characterized by a length incubation period and a chronic course with involvement of the skin, the musculous membranes and the peripheral nervous system Two main types of the disease are described ; the lepromatous and the tuberculoid. In the more malignant lepromatous form, widespread confluent skin lesions occur. Widespread, disabling erythema nodosum is common with diffuse vasculitis. The skin lesions result from the proliferation of histiocytes in the more superficial layers. The small nerves of the skin as well as the walls of the blood vessels are invaded by the bacilli. In the milder, tuberculoid type, the skin lesions are the result of intense host resistance. The small nerves of the dermis are severely infiltrated with early nerve destruction. Nerve involvement is a constant feature of all Mycobacterium leprae infections. The large, peripheral superficially nerves such as the ulnar, radial and peroneal are characteristically affected. Involvement of nerves is responsible for the severe deformities associated to the infection such as foot-drop and claw hands. Loss of skin sensitivity is responsible for iterative injuries, skin lesions and infections, fractures and various skeletal lesions. Atrophy of the tubular bones of the hands and feet with auto-amputation is also due to the nerve involvement. The radiological features of leprosy include, osteitis and osteomyelitis periostitis. The hands and feet are frequently affected. The metaphyses of phalanges are particularly vulnerable. Osteitis affecting hands and feet are of neuropathic type. Such changes consist of terminal tuft erosions followed by fractures and absorption of entire phalanges with « licked candy appearance ». In the foot, progressive resorption of the metatarsal and proximal phalanges occurs. Tarsal disintegration is not infrequent, attributable to sensory and motor dysfunction, trauma and second infection. . Bone sclerosis is common, due to the healing of osseous lesions. During leproma of bone, enlarged nutrient foramina of the phalanges of the hands and cystic like lesions in the distal end of the proximal phalanges of the hand may be present. Specific leprous arthritis is rare affecting the ankle, the knee wrist fingers and elbow. In the tubular bones symmetric periostistis of the tibia, the fibula and the distal portion of the ulna may also be noted. The radiographic appearance of neuropathic osteoarthropathy in leprae is not specific and resembles that in syphilis diabetes mellitus, syringomyelia and congenital insensitivity to pain.
Leprsoy of the feet
Based on the provided foot X-ray images, the following main features can be observed:
Considering the patient’s medical history (leprosy) and the radiological findings, the following possibilities are taken into account:
Combining the patient’s previous diagnosis of leprosy, chronic foot deformity, and the characteristic bone resorption and destruction on X-ray, the most likely diagnosis is:
For further confirmation, a detailed clinical neurological examination, inflammatory markers, and imaging follow-up may be performed. If there is suspicion of superimposed infection, appropriate microbiological testing (culture or biopsy) should be considered.
According to the patient’s condition, treatment should focus on leprosy (if not already managed, continue antibiotic therapy and nerve protection strategies) as well as foot deformities and arthropathies. Below are some feasible approaches:
The goal of rehabilitation exercises is to maintain or improve lower limb and foot function, focusing on strength, balance, and gait training, while avoiding excessive loading that might worsen the damage. The FITT-VP principle can be referenced:
Throughout rehabilitation, careful monitoring of foot skin changes is crucial. Any signs of ulceration or infection should be promptly addressed.
Disclaimer: This report is based on the current imaging and medical history provided and is for reference only. It does not replace an in-person consultation with a qualified physician or further examinations. If you have any questions or changes in your condition, please consult a specialist or visit a hospital promptly.
Leprsoy of the feet
