117 Charcot / Neuropathic Joints

Charcot / Neuropathic Joints

Anthony G. Ryan and Peter L. Munk

Clinical Presentation

A 43-year-old man presented with stiffness and diminished range of motion in his shoulder and right elbow but no pain. He was status 1 year post–motor vehicle accident, at which time he experienced a whiplash injury to the cervical spine but could recall no injury to his upper limbs.

Figure 117A

Figure 117B

Figure 117C

Figure 117D

Figure 117E

Radiologic Findings

An anteroposterior (AP) radiograph of the left shoulder (Fig. 117A) shows no discernible humeral head, a very sharp margin to the end of the proximal humerus, and ossific fragments projected within the confines of the shoulder joint capsule, including a crescentic radiodensity projected lateral to the proximal humerus. The axial view (Fig. 117B) shows the proximal margin of the extant humerus, immediately anterior to which is a faint, round ossific density and through which is projected an ossific “ghost” of the humeral head, both fragments representing the remainder of the humeral head.

AP (Fig. 117C) and lateral (Fig. 117D) radiographs of the right elbow demonstrate multiple well-defined erosions of the capitellum, radial head, coronoid process, olecranon, and destructive erosion of the trochlea. The lateral radiograph in particular demonstrates a dense effusion and multiple large ossific fragments anterior and posterior to the joint.

Further investigations were performed, and a presumptive diagnosis was reached. The left arm was placed in a U-slab for 2 weeks, and a further radiograph of the shoulder was obtained (Fig. 117E), which shows further displacement of the humeral shaft and residual, but less prominent, ossific fragments within the shoulder capsule.

Diagnosis

Neuropathic (Charcot) joint secondary to acquired posttraumatic cervical syrinx (demonstrated on concurrent MRI)

Differential Diagnosis

Calcium pyrophosphate dihydrate deposition disease
Milwaukee shoulder (hydroscyapatite crystal arthropathy)
Septic arthritis

Discussion

Background

Neuropathic arthropathy is a progressive, degenerative arthropathy secondary to an underlying neuropathy. Any condition that leads to loss of sensation in a joint impedes both pain perception and proprioception, resulting in severely altered biomechanics (particularly in weight-bearing joints). This lack of feedback prevents patients from protecting themselves by discontinuing the damaging activity, resulting in repeated traumatic injury.

Etiology

There are two major causes of a denervated joint, congenital and acquired.

CONGENITAL

Myelomeningocele
Congenital indifference/insensitivity to pain

ACQUIRED

Central neuropathy

Trauma: brain, spinal cord injury (Fig. 117F)
Syringomyelia (shoulder)

Figure 117F AP radiograph of the left hip in a quadriplegic patient receiving in-bed physiotherapy. Crepitus heard on passive mobilization prompted the radiograph, which reveals almost complete destruction of the femoral head, disarticulation of the hip joint, and large intra-articular bony fragments.
Neurosyphilis/tabes dorsalis (the condition in which Charcot originally described the joint abnormalities); usually affects the knee
Spinal cord tumors/infection

Peripheral neuropathy

Diabetes mellitus (most common overall cause, affecting between 5 and 10% of diabetics), usually affecting the foot
Leprosy
Peripheral nerve injury
Chronic alcoholism

Iatrogenic

Chronic pain relief medications
Repeated intra-articular steroid injections

Other, less common causes

Scleroderma, Raynaud’s disease, Ehler-Danlos syndrome
Rheumatoid arthritis, psoriasis
Amyloid infiltration of nerves, adrenal hypercorticism
Klippel-Trénaunay-Weber syndrome
Trauma, with or without infection, for example, after fractures and dislocations