KUMJ | VOL. 24 | NO. 1 | ISSUE 94 | JANUARY - MARCH, 2026

Mid-term Results of Core Decompression and Bone Marrow Aspirate Concentrate Therapy for Avascular Necrosis of Hip: A Retrospective Observational Cohort Study
Thapa J, Shrestha D, Shrestha R, Dhoju D, Kayastha K, Parajuli B

Abstract:
Background Core decompression is a surgical procedure done in the early stage of avascular necrosis (AVN) of hip. The addition of bone marrow aspirate concentrate (BMAC) may enhance the outcome compared to the decompression alone. Objective To evaluate the midterm efficacy of core decompression with bone marrow aspirate concentrate therapy in the pre-collapse stage of avascular necrosis of hip. Method This retrospective observational cohort study was conducted on patients with MRIconfirmed avascular necrosis, Association Research Circulation Osseous (ARCO) stage I to IIIa of hip, treated with core decompression and bone marrow aspirate concentrate therapy between 2017 and 2024. Functional outcome and severity of pain were assessed using Modified Harris Hip Score (MHHS) and Visual Analogue Scale (VAS) respectively. Progression of the necrosis and the need for hip replacement were assessed in the regular follow-ups. Kaplan-Meier survival analysis was used to assess survival duration of the femoral head. Result There were 28 hips from 20 patients. The median Modified Harris Hip Score improved from 63.0 (IQR 46-68) to 87.5 (IQR 84-91) (p < 0.001 at -34.67 to -20.52 confidence interval), and the average VAS decreased from 7.5 (IQR 6-8) to 1.5 (IQR 1-2) (p < 0.001 at 4.18 to 5.91 confidence interval). Five hips progressed to the next stage, out of which two required total hip arthroplasty and three were on conservative management. Kaplan-Meier survival analysis showed a cumulative stage progression free survival of 76.7% at 41 months and sustained through 84 months of follow-up. Conclusion Core decompression augmented with bone marrow aspirate concentrate is an effective treatment for pre-collapse stage of avascular necrosis of the hip. It provides significant and rapid symptomatic relief, improves functional outcome, and demonstrates a promising midterm, stage progression-free survival of 76.7%, sustained from 41 to 84 months.
Keyword : Avascular necrosis of hip, Bone marrow aspirate, Core decompression