Neuropathic osteoarthropathy

deterioration of a joint or joints resulting from deprivation of sensory feedback in the musculoskeletal system. Among the specific radiographic abnormalities are joint space narrowing, bone eburnation, osteophytosis, fragmentation, fracture and subluxation. Neuropathic osteoarthropathy is associated with tabes dorsalis, diabetes mellitus, syringomyelia, alcoholism, multiple sclerosis, Charcot Marie Tooth disease, pernicious anaemia, amyloidosis, trauma, Arnold Chiari malformation, neurofibromatosis, congenital indifference to pain and meningomyelocoele, among other conditions. Originally the term Charcot joint was given to the articular manifestations of patients with tabes dorsalis, but this term has now become synonymous with all articular abnormalities related to neurologic deficits, regardless of the underlying primary disease. Hypertrophic changes are commonly associated with central spinal cord lesions, whereas atrophic manifestations are typically linked to peripheral nerve injuries.

On radiographs, early features may resemble those of osteoarthritis, but if effusion, minimal subluxation, fracture, considerable amounts of cartilaginous and bony debris within the synovial membrane (detritic synovitis) and fragmentation are present, the existence of neuropathic osteoarthropathy should be suspected. Later manifestations include depression, absorption and shattering of subchondral bone, significant sclerosis and osteophytosis, intra-articular bone fragments, subluxation, massive soft tissue enlargement and effusion, and fracture of neighbouring bones. Ultimately, the joint reveals disorganization, with both bone resorption and bone formation occurring simultaneously. See pain, congenital indifference to (III:1), Fig. 1.

Although the radiographic and pathologic features of this neuropathic osteoarthropathy are generally similar in the various disorders associated with this abnormality, the distribution of the abnormalities varies (Table 1).

Neuropathic osteoarthropathy, Table 1. Typical sites of involvement in some conditions associated with neuropathic osteoarthropathy.

Disease Site of involvement
tabes dorsalis Knee, hip, ankle, spine
syringomyelia Glenohumeral joint, elbow, wrist, spine
diabetes mellitus Metatarsophalangeal, tarsometatarsal, intertarsal joints
Alcoholism Metatarsophalangeal, interphalangeal joints
amyloidosis Knee, ankle
meningomyelocoele Ankle, intertarsal joints
Congenital sensory neuropathy, hereditary sensory radicular neuropathy Knee, ankle, intertarsal, metatarsophalangeal, interphalangeal joints
Idiopathic Elbow, shoulder