Inclusion Criteria:

• Males and females, 22-70 years of age.
• No articular surface collapse of the femoral heads as measured by MRI.
• Target disease or condition: Bilateral pre-collapse osteonecrosis of the femoral head.
• Atraumatic osteonecrosis of the femoral head (all other etiologies eligible including corticosteroid and alcohol induced osteonecrosis).
• Ability to safely undergo liposuction that will result in the harvest of a sufficient quantity of adipose tissue (approximately 360 mL).  A plastic surgeon evaluation will be performed in order to determine adequate adipose tissue is available for harvest.
• Capacity to provide informed consent.
• Ability to comply with protocol.
• Normal laboratory values of CBC, CRP, AST, ALT, Bilirubin (total & direct), BUN and Creatinine.

Exclusion Criteria:

• Post traumatic femoral head osteonecrosis.
• Osteonecrosis of the femoral head in stages ≥ IIIA according to the Steinberg classification.
• Asymptomatic osteonecrosis on exam.
• Flattening of the femoral head (Steinberg classification Type IV) or articular cartilage collapse at the time of core decompression surgery.
• Septic arthritis, stress fracture, or non-osteonecrosis metabolic bone diseases (e.g., Paget’s disease of bone, osteogenesis imperfecta, primary hyperparathyroidism, osteopetrosis, and fibrous dysplasia including monostotic, polyostotic, and McCune-Albright syndrome).
• Skeletal immaturity.
• Known history of HIV, or has active Hepatitis B or active Hepatitis C.
• Disease or medication-related disorder of coagulation (i.e., elevated PTT > 13.8 seconds, INR > 1.2, or low platelet count < 150 x 10^9/L). Patients on coumadin, heparin products, and novel oral anticoagulants will be excluded. Antiplatelet medications (e.g., aspirin, clopidogrel) are permitted as long as the aforementioned coagulation labs are within the specified range.
• Patients who have aPTT values greater than or equal to 1.8 times the normal limit.
• Patients who are actively or recently received glycoprotein IIb/IIIa inhibitors (abciximab/ ReoPro, Aggrastat/ tirofiban, eptifibatide/ Integrilin).
• All patients who have inadequate fat deposits (i.e., < 200 ml of lipoaspirate from 3 bilateral sites) will be excluded from the study.
• Lumbar radiculopathy, and/or neurogenic or vascular claudication.
• Active Skin infection at the time of surgery.
• Active Local bone infection.
• Patients in active treatment for cancer or a blood dyscrasia, or having received chemotherapy, radiotherapy or immunotherapy in past 1 year.
• Participation in another clinical study in the past 30 days or concurrent participation in another clinical trial.
• MRI-incompatible internal devices (pacemakers, aneurysm clips, etc).
• Patients with poorly controlled diabetes mellitus (HbA1C ≥ 8%), peripheral neuropathy, or severe vascular problems.
• Patients receiving treatment with hematopoietic growth factors or anti-vasculogenesis or anti-angiogenesis treatment (e.g., anti-VEGF).
• Patients requiring bisphosphonate treatment for study duration.
• Pregnant or lactating female patients.
• Prisoners.
• Known starch or gentamycin allergy.
• Known amylase deficiency.
• Laser- or ultrasound-assisted lipoaspiration technique is used during the lipoaspiration procedure.
• An adverse event that meets one or more fat harvest stopping rules has occurred during the lipoaspiration procedure.
• Positive gram stain result on ADRC product prior to administration.
• If final viable cell count of ADRC product is < 34 million.