Subchondral Insufficiency Fracture of the Femoral Head in a 41 Year Old: A Case Report

Case Diagnosis: 41-year-old male with a subchondral insufficiency fracture of the femoral head (SIFFH).

Case Description or Program Description: The patient presented with 3 months of atraumatic, insidious left superolateral thigh pain radiating to the groin and calf, aggravated with prolonged sitting, walking, and standing. Non-steroidal anti-inflammatories (NSAIDs), acetaminophen, ice and massage provided no relief. Exam revealed left superolateral thigh, lateral glute, and anterior groin tenderness, with positive supine straight leg raise and FADIR. Lower limb strength, sensation and reflexes were normal. Initial presentation was concerning for lumbosacral radiculopathy, however, lumbar MRI was normal. Left hip/pelvis radiographs revealed hip osteoarthritis and possible avascular necrosis (AVN). Subsequent hip MRI excluded AVN but revealed a 16x15mm subchondral fracture in the anterosuperior femoral head.
Treatment consisted of offloading with crutches, physical therapy (PT) and NSAIDs. Orthopedic surgery was consulted; surgical intervention was not indicated.

Setting: Outpatient musculoskeletal clinic

Assessment/Results: The patient successfully returned to activities after 14 weeks of PT and gait training. PT progression included active range of motion and heel touch weight-bearing (WB) week 1-2, proximal hip stabilization and 25% WB week 3-4, and resistance training with 50% WB weeks 4+. By 6 weeks his pain had significantly improved with return to WB without crutches. A DEXA scan showed osteopenia (T-scores: -1.2 left, -1.6 right), prompting an endocrinology referral for evaluation of endocrine pathology and nutrient deficiencies.

Discussion (relevance): SIFFH is most commonly seen in elderly women with osteoporosis. It is uncommon in young and middle-aged adults, and may be misdiagnosed as it can mimic lumbosacral radiculopathy or other hip pathology. X-rays are often normal and early MRI is crucial for diagnosis.

Conclusions: Insufficiency fractures can occur when normal stress is applied to abnormal bone. In otherwise healthy middle-aged adults, SIFFH diagnosis warrants investigation into nutrient deficiencies and/or hormonal imbalances. Early intervention including WB restrictions and PT is important in preventing symptom progression.