Avascular Necrosis (AVN) Long-Term Follow-up

Patients enrolled at investigational sites who had Stage I or Stage II Osteonecrosis of the femoral head and who would qualify for core decompression based upon physical and radiographic exam and medical history.

Inclusion Criteria:

• Patient qualifies for core decompression based on physical exam
• No history of core decompression
• Patient is willing and able to provide written informed consent

Exclusion Criteria:

• Patient has been diagnosed as Stage 0, III, IV, V or VI using the Steinberg/UPenn staging system.
• Patient's BMI is >40
• Patient is mentally compromised
• Patient has neurological condition in ipsilateral or contralateral limb, which affect lower limb function
• The patient has had a proximal femoral osteotomy or internal fixation in the affected hip.
• The patient has undergone previous treatment for AVN
• Previous hip conditions
• Patient's bone stock is insufficient
• Patient has diagnosed systemic disease
• Patient is a pregnant female
• Patient is unable or unwilling to attend postop follow-up visits
• Patient has received investigational drug within the previous 6 months or an investigational device within the last 12 months
• Patient has an active or latent infection
• Patient has metal sensitivity
• Patient is a prisoner