M87.373
BillableOther secondary osteonecrosis, unspecified ankle
HCC Category Mapping
V28HCC 92 — Bone/Joint/Muscle Infections/Necrosis
0.209V24HCC 39 — Bone/Joint/Muscle Infections/Necrosis
0.482ESRDHCC 39 — Bone/Joint/Muscle Infections/Necrosis
0.000RxHCCHCC 80 — Bone/Joint/Muscle Infections/Necrosis
0.000What This Code Means
Death of bone tissue in the ankle caused by an underlying condition or treatment, with the side not specified.
Coding Tips
- •Query provider to determine laterality (right vs. left) rather than using unspecified code when possible
- •Ensure secondary cause documentation is present to justify the diagnosis and guide treatment
Clinical Significance
This diagnosis represents secondary osteonecrosis of the ankle when laterality is not specified, caused by underlying conditions that can significantly impact mobility and weight-bearing. It requires identification of the causative factor and monitoring for joint complications.
Documentation Requirements
- ✓Documentation of osteonecrosis affecting ankle without side specification
- ✓Identification of underlying cause (e.g., corticosteroid use, radiation therapy, previous trauma)
- ✓Imaging findings confirming ankle bone necrosis
- ✓Clinical symptoms such as ankle pain, swelling, or stiffness
- ✓Functional limitations affecting walking and weight-bearing
- ✓Duration and progression of condition
- ✓Treatment history and response
- ✓Reason why laterality cannot be determined or if bilateral involvement
Commonly Confused Codes
M87.371 — Other secondary osteonecrosis, right ankle (when laterality is known)M87.372 — Other secondary osteonecrosis, left ankle (when laterality is known)M86.179 — Chronic osteomyelitis of unspecified ankle (infection vs necrosis)S93.409A — Sprain of unspecified ligament of unspecified ankle (acute injury vs necrosis)M19.079 — Primary osteoarthritis of unspecified ankle (arthritis vs necrosis)
Code Hierarchy
└M87Osteonecrosis└M87.3Other secondary osteonecrosis└M87.37Other secondary osteonecrosis, ankle and foot└M87.373Other secondary osteonecrosis, unspecified ankle
└M87.373Other secondary osteonecrosis, unspecified ankle