Bone graft substitutes in hip revision surgery: a comprehensive overview

INTRODUCTION

Total hip replacement is increasingly used to treat diseased and damaged joints. With time, some joint replacements may require revision, mainly because of instability and mechanical loosening, and this is of particularly significance to younger patients. A major problem in revision surgery is the loss of bone stock and the consequent difficulty in reconstructing a stable joint. Loss of bone stock has been widely treated using bone autografts and allografts but supplies are limited. Use of bone graft substitutes in combination with, or as a substitute for, human bone is a possible alternative.

AIM

To identify empirical studies of bone graft substitutes in hip revision surgery.

METHODS

Systematic review based on Cochrane and MOOSE methods. We searched MEDLINE and EMBASE to December 2010 with terms relating to hip replacement and bone graft substitutes, and checked key citations in ISI Web of Science and reference lists. We considered all human studies irrespective of study design.

RESULTS

Searches identified 397 articles. Screening of abstracts and full text articles identified 7 studies reporting outcomes of bone-graft substitute combined with autograft or allograft, and 6 studies reporting outcomes of bone graft substitute exclusively. One economic evaluation compared costs of femoral head banking with costs of bone graft substitutes. No randomised controlled trials evaluating bone graft substitute effectiveness were identified. Studies generally included small numbers of patients with a follow up too short to assess outcomes relating to implant survival. However, excepting those based on glass ceramic, ceramic bone graft substitutes show promise as an alternative to use of exclusive autograft or allograft. In the case of calcium phosphate ceramic bone graft substitute, potential cost savings were evident.

CONCLUSION

With increased allograft shortage, bone graft substitutes will be required in hip revision surgery. However, appropriately designed randomised controlled trials are required to compare use of existing and new bone graft substitutes with established practice. As well as prosthesis related outcomes, studies should explore the patient experience of revision hip replacement with bone graft substitute material.

The Use of Ceramics as Bone Substitutes in Revision Hip Arthroplasty

The number of grafting procedures, including those performed in primary and revision hip arthroplasty, continues to rise around the world. Demand for musculoskeletal donor tissue now outstrips supply. There is no single bone substitute that is ideal for all circumstances. Bone substitutes act as a scaffold and are usually osteoconductive. They are rarely osteoinductive; if they are, a molecular bond is formed between the graft and host bone, improving fixation and longevity. Bone graft substitutes are very rarely osteogenic. There is a growing body of clinical evidence supporting the use of bone graft substitutes in vivo for complex hip arthroplasty.

Use of cancellous bone chips and demineralized bone matrix in the treatment of acetabular osteolysis: preliminary 2-year follow-up

Twenty patients (20 hips) who had cementless acetabular revision arthroplasty and were treated with cancellous bone chips mixed with demineralized bone matrix to fill the cavitary defects were studied. At 2-years' follow-up, the grafts were fully incorporated in 18 patients. In addition, the mean Harris Hip Score increased to 89 points from a mean preoperative score of 29 points for the surviving hips. These preliminary findings suggest that the prepackaged demineralized bone matrix and cancellous chips can provide acceptable radiographic and clinical results as an adjunct in the treatment of contained osteolytic acetabular defects.