A diabetic patient develops Charcot neuroarthropathy of the midfoot (rocker bottom deformity). The primary pathophysiological mechanism is:
- A Repetitive unrecognized trauma on an insensate foot causing fracture-dislocation with hyperemic bone resorption ✓
- B Ischemia of subchondral bone from microvascular disease
- C Osteomyelitis from plantar ulcer spreading to midfoot joints
- D Reactive arthritis from recurrent infections
Correct answer: A. Repetitive unrecognized trauma on an insensate foot causing fracture-dislocation with hyperemic bone resorption
Explanation
Charcot neuroarthropathy (CN) results from loss of protective sensation allowing repetitive microtrauma and unrecognized fracture-dislocations. Autonomic neuropathy causes increased blood flow and osteoclast activation (neurovascular theory), leading to rapid bone resorption and destruction. The combination produces progressive midfoot collapse into rocker bottom deformity. Microvascular ischemia causes ulceration and infection separately; osteomyelitis is a complication rather than the cause of Charcot.
Reference: Maheshwari Essential Orthopaedics, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.