Neuropathic Osteoarthropathy

Radiographic findings may include:

  • subchondral resorption
  • mixed ill-defined increased and decreased densities (not forefoot)
  • loss of apposition between bones at joints
  • loose osseous bodies (aka "joint mice")
  • arthritis mutilans (forefoot)
  • periostitis (forefoot)
  • osteolysis

Differential Diagnosis:

  • septic arthritis
  • psoriatic arthritis (in forefoot)

Podcast

The following enhanced podcast includes images. Save it to your computer (right-click‚ÜíSave As...). (Left-clicking on the podcast link will only play the audio portion with no images.)

Here are classic presentations of neuropathic osteoarthropathy:

  • Case 1a
  • Case 1b
  • *Case 1a
  • *Case 1b
  • Case 2a
  • Case 2b
  • *Case 2a
  • *Case 2b
  • Case 3
  • *Case 3
  • Case 4
  • *Case 4
Charcot DP
Charcot Lateral

Charcot DP

DP view. Findings include subchondral resorption (R); mixed lucency (L) and sclerosis (S) involving affected bones; loss of apposition (A) (partial and total) between adjacent bones at several joints; fragmentation/loose osseous bodies (O).

Charcot Lateral

Lateral view. Findings include subchondral resorption (R); mixed lucency (L) and sclerosis(S) involving affected bones; loss of apposition (A) (partial and total) between adjacent bones at several joints; fragmentation/loose osseous bodies (O).

Charcot DP
Charcot lateral

Charcot DP

DP view. Same findings as case 1 but more pronounced. R = subchondral resorption; A = loss of 100% apposition between bones at joints; S = sclerosis; L = lucency.

Charcot lateral

Lateral view. Same findings as case 1 but more pronounced. O = Loose osseous bodies; S = sclerosis; L = lucency.

Charcot DP Charcot Lateral

Charcot DP Charcot Lateral

DP and lateral views. Subchondral resorption (R), fragmentation (loose osseous bodies, O) and osteolysis predominate. There also is loss of apposition between the metatarsal head and proximal phalangeal base (A). Note that there is no evidence of sclerosis (i.e., increased density) (the bones appear "brighter" in the lateral view as a result of editing so that the hallux would become more visible).

Charcot forefoot

Charcot forefoot

DP view. Arthritis mutilans. The heads and bases of all lesser ray metatarsals and bases, respectively, are absent and the remaining diaphyses are tapered. (R = subchondral resorption; L = lucency.) List the five figurative terms/phrases for arthritis mutilans. Diagnosis: neuropathic osteoarthropathy.

Should a radiographic study be ordered for suspicion of neuropathic osteoarthropathy?

Definitely yes.

What are the best views to order?

At a minimum order DP and lateral views. Oblique views can be valuable adjunct views but are not necessary.

How is this pathology radiographically similar (or different) to septic arthritis or psoriatic arthritis?

Septic arthritis (without other superimposed pathology) is almost always monarticular.

Psoriatic arthritis may be indistinguishable radiographically when it presents as arthritis mutilans.

Other information

Diabetes is the leading cause of neuropathic osteoarthropathy. What are other causes?

Its radiographic presentation varies depending on which joints are affected. Generally speaking, the findings demonstrated at LisFranc's joint in cases 1 & 2 appear similarly at the intertarsal and ankle joints. However, in the forefoot, the predominant finding is bone resorption and osteolysis (AKA arthritis mutilans).

References:

  1. Resnick, D: Bone and Joint Imaging, 2nd edition, WB Saunders, 1996.
  2. Christman RA: Foot and Ankle Radiology, 2nd edition, Lippincott Williams & Wilkins, 2015.