Osteonecrosis of the femoral head (ONFH), resulting from impaired blood supply to the head of the femur, presents a significant challenge to clinicians due to its debilitating nature. Conservative treatment often offers insufficient pain relief and debilitating functional outcomes which necessitate alternative therapies. Bone marrow aspirate concentrate (BMAC), a potent orthobiologics and rich in mesenchymal stromal cells and growth factors, holds good promise as the minimally invasive procedure for ONFH. With the preceding research suggesting clinical and functional efficacy, we assessed the therapeutic effectiveness of BMAC in ONFH management in joint preservation. A prospective cohort study was conducted with 20 patients suffering from ONFH who failed to respond to 6 months of conservative treatment. A uniform surgical procedure was performed by a single surgeon, involving bone marrow extraction from the anterior iliac crest and subsequent processing into an 8-10 mL of BMAC concentrate. The BMAC was then injected into the implanted into the decompressed femoral head. The post-operative protocol comprised weight-bearing mobilization, physiotherapy, and a 4-week NSAID-free regimen. Outcome measures included pain scores, hip function, knee symptoms, sports activities, patient satisfaction, and recommendation of the procedure. Of the 20 patients suffering from ONFH, primarily the left side, most of whom were at stage 2b, significant pain reduction and functional improvement were observed over 24 months. The mean pain score decreased from 9.00 to 3.55, while the hip function score increased from 46.12 to 88.60. However, some patients encountered complications such as symptom recurrence (5%), disease progression (10%), and persistent pain (5%). Core decompression with BMAC implantation emerges as a promising, effective, and safe treatment for ONFH with better costeffectiveness and minimal side effects, making it a feasible treatment alternative.