Fig. 1From: Mid-term outcomes of arthroscopic-assisted Core decompression of Precollapse osteonecrosis of femoral head—minimum of 5 year follow-upa Preoperative plain AP X-ray of left hip demonstrating a Stage IIa osteonecrotic lesion. b MRI T1-weighted coronal image of left hip shows a geographic pattern of the necrotic areaBack to article page