Background

Post-traumatic immunosuppression (PTI) after surgery increases vulnerability to nosocomial infections, sepsis, and death. Knee arthroplasty offers a sterile clinical model to characterise PTI and explore its underlying mechanisms.

Bone stock loss is a major challenge to the revision hip surgeon. Impaction grafting is frequently the preferred option for the surgeon when faced with bone stock deficiency. This retrospective study assesses a consecutive series of patients who underwent revision hip replacement with femoral impaction grafting during the period 1994–2001. Radiographic measurement for stem subsidence was carried out by 2 independent observers on pre-operative and post-operative radiographs at 6 months, 1 year, 18 months and 2 years following surgery. Graft incorporation and trabecular remodelling were also subjectively assessed. Irradiated bone allograft was used in all cases.

Sixty-nine hips were reviewed. Radiographic analysis revealed graft incorporation in 38% of cases. However, there was no evidence of trabecular remodelling. Moderate subsidence (5–10 mm) occurred in 10 cases (14.5%), and massive subsidence (> 10 mm) occurred in 5 cases (7.2%). The survivorship with re-revision or need for further surgery as the end point was 92.8% at an average of 28 months.

The results obtained in this study are less favourable than other reported studies of revision of the femoral stem using impaction bone grafting. The absence of the characteristic changes of graft remodelling reported in other series raises concerns that irradiated bone graft may be a significant factor in the post-operative progress.

Introduction: Impaction bone grafting is a very useful technique in the armament of a revision hip surgeon. Traditionally fresh frozen allograft has been used for this technique. However there are concerns about the transmission of viral proteins and prions through this form of allograft.As a result irradiated bone graft has been favoured in some centres. There is no long term series describing the results of impaction bone grafting using irradiated bone

Method: We describe a series of 58 cases of acetabular revision surgery done at the Avon Orthopaedic Centre between 1995 and 2001 and followed up over a period of 48–90 months. The preoperative bone defect was graded by the Paprosky classification. There were 10cases of type 1,15 type 2a, 5 type 2b, 7 type 2c, 14 type 3a and 7 type 3c.50 cases were operated by the two senior surgeons and 8 were senior trainees.All uncontained defects were first contained by using a mesh or cages. The bone graft used was freeze-dried femoral head allograft, which was milled and used without defatting. The cases were followed up clinically and radiologically.Case notes were reviewed to gain information about the primary prosthesis, and operative details as well as the cause of the revision. All the cases were the first revisions.

The radiological picture was evaluated for signs of incorporation, remodelling, loosening and migration of the cemented acetabular component. Clinical evaluation was from the last clinic visit and included the presence of pain, mobility status, range of movement and patient satisfaction. Revision was the end point of the study

Results: There were no cases which underwent loosening and all the cups were stable.1 case had recurrent dislocation and was revised.26 (44.8%) cases showed changes of incorporation, and 4 cases (6%)showed changes of remodelling.23 cases (39.6%) underwent femoral impaction grafting as well. Clinically the results were satisfactory with absence of pain in 38 cases (65%). Trochanteric pain was present in 3 cases.

Conclusion: The results suggested that the results of impaction bone grafting on the acetabular side using irradiated bone graft are comparable to those with fresh frozen allograft and significantly better than those on the femoral side. This could be attributed to the compressive forces acting across the acetabular side as against the predominantly shear forces acting on the femur. The low percentage of remodelling remains a concern and warrants further studies.