Differential Diagnosis
- Single most likely diagnosis
- Gout: The presence of mild medial subluxation of the first metatarsophalangeal joint, a common site for gouty arthritis, along with a plantar calcaneus spur, suggests a chronic inflammatory condition like gout. Vascular calcification around the ankle joint could be related to chronic inflammation and metabolic disturbances associated with gout.
- Other Likely diagnoses
- Rheumatoid Arthritis (RA): Although less common in the first metatarsophalangeal joint compared to other joints, RA can cause subluxation and has systemic manifestations that could include vascular calcifications.
- Psoriatic Arthritis: This condition can cause joint subluxation and has associations with enthesitis (inflammation at the sites where tendons or ligaments insert into the bone), which could explain the plantar calcaneus spur.
- Osteoarthritis: While primarily a degenerative condition, osteoarthritis can lead to subluxation and has associations with bone spurs. However, vascular calcification is less commonly associated with osteoarthritis.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Charcot Arthropathy: A condition that can lead to significant joint destruction and subluxation, often in the context of diabetes or other neuropathic conditions. Vascular calcification could be seen in the context of diabetes.
- Septic Arthritis: An infectious condition that requires immediate attention to prevent joint destruction. While less likely given the chronic nature of the findings, it's crucial not to miss this diagnosis.
- Rare diagnoses
- CPPD (Calcium Pyrophosphate Deposition Disease): A condition that can cause joint subluxation and has associations with calcifications, including vascular calcifications in rare cases.
- Hemochromatosis: A genetic disorder leading to iron overload, which can cause arthritis, skin pigmentation, and potentially vascular calcifications due to associated metabolic disturbances.