Management of Bone Marrow Lesions of the Hip With Subchondral Calcium Phosphate Injection: Surgical Technique and Tips

Abstract

Bone marrow lesions (BMLs) are localized areas of edema within subchondral bone, which are often due to early chondromalacia changes, subchondral insufficiency stress or microfractures, and/or avascular necrosis. The presence of BMLs worsen outcomes after arthroscopy and arthroplasty, thus making their management important in the preservation of hip function. In recent years, the advent of Subchondroplasty (SCP; Zimmer Knee Creations Incorporated, Exton, PA)da minimally invasive surgical technique that involves injecting an isothermic calcium phosphate solution to stabilize BMLsdhas shown promising results in managing pain from osteoarthritis (OA). The SCP material (AccuFill Bone Substitute Material, Zimmer Knee Creations Incorporated) has a similar physical and chemical structure to native bone mineral. In this Technical Note, we discuss a surgical approach for managing acetabular and femoral head BMLs with SCP. We also review the prior clinical trials reporting on SCP for knee OA. SCP may be a promising technique as part of the treatment algorithm for managing hip OA, and clinical trial enrollment has begun for hip SCP. On the basis of these results, further investigations into this procedure may be warranted.

Arthroscopic Approach to Preservation of the Hip with Avascular Necrosis

“… 26 Minimally invasive arthroscopy-assisted techniques have been described. 6 , 27 Recent trends in treating early AVN are toward the combination of CD with biomaterials. 28 Subchondroplasty, which includes the injection of CaPO 4 material in addition to CD, is an emerging surgical technique with good outcomes in subchondral lesions around the knee.…”

“… 3 Subchondroplasty is increasingly adopted in treating cystic lesions in the femoral head and acetabulum during hip arthroscopy, which shows the importance of combining fluoroscopy with arthroscopy for the successful treatment of intra-articular hip pathologies. 6 , 9 CaPO 4 substitute has shown better biomechanical behavior in maintaining articular congruency in tibial plateau fractures compared with autologous bone. 34 Moreover, AccuFill (Zimmer), which was used in this case, is a nanocrystalline CaPO 4 injectable solution that has proven its efficacy and demonstrated adequate implantation into the trabecular bone among different bone substitute materials.…”

“…7,8 A similar approach has been described in the hip, but clinical outcomes are less evaluated. 6,9 Concomitant central compartment pathology, including femoroacetabular impingement (FAI) as well as chondral and labral lesions, is frequently present in the context of femoral head AVN. [10][11][12] There is an increasing body of evidence that FAI can lead to cartilage wear and eventual osteoarthritis.…”

“… 5 Femoral head subchondroplasty is a minimally invasive core decompression (CD) technique with bone substitute injection into the subchondral bone. 6 Promising results have been recently reported with the advent use of calcium phosphate (CaPO 4 ) solution in subchondral lesions around the knee. 7 , 8 A similar approach has been described in the hip, but clinical outcomes are less evaluated.…”

“… 7 , 8 A similar approach has been described in the hip, but clinical outcomes are less evaluated. 6 , 9 …”