Biphasic bone graft substitute in revision total hip arthroplasty with significant acetabular bone defects

Abstract

Aims Large acetabular bone defects encountered in revision total hip arthroplasty (THA) are challenging to restore. Metal constructs for structural support are combined with bone graft materials for restoration. Autograft is restricted due to limited volume, and allogenic grafts have downsides including cost, availability, and operative processing. Bone graft substitutes (BGS) are an attractive alternative if they can demonstrate positive remodelling. One potential product is a biphasic injectable mixture (Cerament) that combines a fast-resorbing material (calcium sulphate) with the highly osteoconductive material hydroxyapatite. This study reviews the application of this biomaterial in large acetabular defects. Methods We performed a retrospective review at a single institution of patients undergoing revision THA by a single surgeon. We identified 49 consecutive patients with large acetabular defects where the biphasic BGS was applied, with no other products added to the BGS. After placement of metallic acetabular implants, the BGS was injected into the remaining bone defects surrounding the new implants. Patients were followed and monitored for functional outcome scores, implant fixation, radiological graft site remodelling, and revision failures. Results Mean follow-up was 39.5 months (36 to 71), with a significant improvement in post-revision function compared to preoperative function. Graft site remodelling was rated radiologically as moderate in 31 hips (63%) and strong in 12 hips (24%). There were no cases of complete graft site dissolution. No acetabular loosening was identified. None of the patients developed clinically significant heterotopic ossification. There were twelve reoperations: six patients developed post-revision infections, three experienced dislocations, two sustained periprosthetic femur fractures, and one subject had femoral component aseptic loosening. Conclusion Our series reports bone defect restoration with the sole use of a biphasic injectable BGS in the periacetabular region. We did not observe significant graft dissolution. We emphasize that successful graft site remodelling requires meticulous recipient site preparation. Cite this article: Bone Jt Open 2022;3(12):991–997.

Mouldable Collagen–Tricalciumphosphate Is a Safe Carrier for Local Antibiotics—Short-Term Results in Revision Hip Arthroplasty

“…While there is no consensus on the general use of local, calcium-based, degradable antibiotic carriers due to the lack of robust literature [ 9 ], there are promising results from individual centres. One study [ 19 ] investigated the use of a synthetic composite calcium sulphate/hydroxyapatite in complex hip revision arthroplasty in 49 patients. The authors used the composite material for acetabular augmentation in combination with calcium sulphate beads as an antibiotic carrier in the joint.…”

“…While wound leakage and conservative treatment has been described for the use of ceramic antibiotic carriers in the treatment of osteomyelitis [ 29 ], wound drainage after arthroplasty revision requires revision surgery, especially in the treatment of fulminant infections. Given that wound revision was not a major issue in previous studies [ 18 , 19 ] of hip revision surgery using a calcium-based (composite) bone graft as a local antibiotic carrier, it is unclear whether the cases of seroma with wound drainage were due to persistent/recurrent infection or if they could be related to the use of the composite bone graft. As a high number of patients had megaimplants on the femoral side or had undergone previous failed treatment for PJI; the higher revision rate and potential dead space must be considered and could potentially explain the rate of complications found [ 32 , 33 , 34 ].…”

“…However, clinical studies on the use of such materials in hip PJI are limited by small sample sizes and heterogeneous use of different bone substitutes, which makes it difficult to determine appropriateness of their use in these complex cases [ 18 , 19 ]. To our knowledge, published articles regarding the usage of β-TCP collagen composite, as shown in Figure 1 , are sparse and limited to case reports [ 20 ].…”