Acetabular reconstruction with impaction bone grafting and cemented polyethylene socket in total hip revision arthroplasty.

BACKGROUND AND AIMS: Bone deficiency in revision total hip arthroplasty is a challenge to the surgeon. One option for restoration of the bone stock is impaction bone grafting and use of a cemented socket. The aim of this study was to evaluate the mid-term clinical outcome of impaction bone grafting and cemented socket revisions. MATERIAL AND METHODS: A total of 59 patients (60 hips) underwent revision arthroplasty with impaction bone grafting and application of a cemented socket on the acetabular side in the Turku University Hospital from 1999 to 2004. The study end-point was re-revision for any reason. The cumulative percentages for survival were followed and estimated with Kaplan-Meier curves. Associations between occurrence of re-revision and potential risk factors were analyzed with logistic regression. Results were quantified by odd ratios and 95% confidence intervals. The mean age of the patients was 69 years (33% male). A total of 3% of the patients had a class I Paprosky acetabular defect, 38% had class II, and 55% had class III. RESULTS: The overall survival rate was 73%. The mean follow-up time was 7 years. The most common reason for re-revision was aseptic loosening of the acetabular component (13 patients, 81% of re-revisions). Cox's regression analysis did not identify any risk factors for re-revision. CONCLUSION: Our results were inferior compared to some previous studies. Impaction bone grafting of acetabular defects in revision total hip arthroplasty may not always provide a reliable bone stock in long-term.

Experience of structural onlay allografts for the treatment of bone deficiency in revision total hip arthroplasty.

BACKGROUND AND AIMS: Loss of femoral bone stock in elective revision total hip arthroplasty poses unique and substantial challenges. Structural onlay allografts may provide mechanical stability for the cementless revision prosthesis and increase bone stock. MATERIAL AND METHODS: At least one cortical onlay allograft was used in 40 elective total hip arthroplasty revisions (40 patients) to reconstruct femoral bone defects. The operations were performed between January 1999 and August 2010 in the Turku University Hospital, Finland. The mean follow-up time was 52 months (range: 12-125 months). RESULTS: The allografts were incorporated into the bone tissue in 37 of 40 (92.5%) patients. Cementless revision stems healed in 36 of 40 (90.0%) patients, but these patients were not exactly the same patients whose allografts were successfully incorporated. One or more surgical complications were experienced by 14 of 40 (35.0%) patients during follow-up. In all, 4 of 40 (10.0%) patients (all women) had hip infections during follow-up. Of the 7 patients with rheumatoid arthritis, 4 (57.1%) had at least one complication. CONCLUSIONS: The use of the cortical onlay allografts provides a feasible option for restoring the integrity of the proximal femur in revision total hip arthroplasty, but the complication rate is high, particularly in female patients with rheumatoid arthritis.

Cementless total hip arthroplasty with large diameter metal-on-metal heads: short-term survivorship of 8059 hips from the Finnish Arthroplasty Register.

BACKGROUND AND AIMS: Population-based register data from the National Joint Register of Australia and England and Wales have revealed that the mid-term outcome of cementless large diameter head metal-on-metal total hip arthroplasty is inferior to that of conventional cemented metal-on-polyethylene total hip arthroplasty. The aim of this study was to compare the results of cementless large diameter head metal-on-metal total hip arthroplasty with conventional cemented arthroplasty in Finland. The second aim of this study was to compare the cementless large diameter head metal-on-metal models with each other. MATERIAL AND METHODS: Based on the data extracted from the Finnish Arthroplasty Register, the risk of revision of 8059 cementless large diameter head metal-on-metal total hip arthroplasties performed during 2002-2009 was analyzed using Cox regression model. The revision risk of these hips was compared to that of 16,978 cemented metal-on-polyethylene total hip arthroplasties performed during the same time period. RESULTS: In the Cox regression analysis, there was no difference in revision risks between cementless large diameter head metal-on-metal total hip arthroplasty and cemented metal-on-polyethylene total hip arthroplasty (relative risk = 0.90, confidence interval = 0.74-1.10, p = 0.3). However, in female patients aged 55 years or above, cementless large diameter head metal-on-metal total hip replacements showed a significantly increased risk of revision as compared to cemented total hip replacements (relative risk = 1.33, confidence interval = 1.04-1.70). Compared to the reference implant in this study (cementless Synergy stem combined with Birmingham Hip Resurfacing [BHR] cup), the CementLess Spotorno (CLS) stem combined with Durom cup had a 2.9-fold (95% confidence interval = 1.17-6.90) increased risk of revision. CONCLUSIONS: We found that cementless large diameter head metal-on-metal total hip arthroplasty had short-term survivorship compared with cemented total hip arthroplasty at a nation-wide level. However, in female patients aged 55 years or above, cementless large diameter head metal-on-metal total hip arthroplasty showed inferior results. Furthermore, implant design had an influence on revision rates. Longer follow-up time is needed to assess the success of large diameter head metal-on-metal total hip arthroplasty.

Early results of large head metal-on-metal hip arthroplasties.

BACKGROUND AND AIMS: Total hip arthroplasty significantly improves patient's life quality. However, total joint replacement is associated with possible complications, such as dislocations, infections, fractures and periprosthetic osteolysis. The goal of this study was to evaluate a large head metal-on-metal total hip arthroplasties and analyse short term complications related to them. MATERIAL AND METHODS: Between 9/2005 and 6/2009, a total of 691 hip replacements were performed on 635 patients with the use of Magnum M2 large head cementless metal-on-metal prosthesis in Turku University Hospital. All patients had a scheduled follow-up at two to three months, and at one year. The results were evaluated using X-rays, Harris Hip Score (HHS), and evaluating post-operative complications and reasons for re-operations. RESULTS: During our follow-up the HHS median raised from its preoperative value of 59.8 to 86.4 two to three months after the operation, and to 93.9 one year after the operation. As a complication we had five infections requiring single open debridement (early infection) or a two stage revision. Seven patients had a periprosthetic femoral fracture that was operated and 11 patients were reoperated because of acetabular component malposition, fracture or early loosening. We did not observe any dislocations, n. ischiadicus damages, squeeking or complications related to high metal ion release (ALVAL-reactions (Aseptic Lymphocyte-dominated Vasculitis-Associated Lesion) or pseudotumours). CONCLUSIONS: The metal-on-metal bearing pair allows large femoral head size, which decreases the risk for dislocation. It may also decrease the risk for osteolysis and aseptic loosening in a long run. Early complication rate related to the bearing surface is minimal. Metal-on-metal prosthesis is a good choice for young and active patients with good bone quality.

Up to 10 years follow up of the use of 71 cortical allografts (strut-grafts) for the treatment of periprosthetic fractures.

BACKGROUND AND AIMS: Periprosthetic fractures are often located in areas of poor bone quality. There are multiple strategies to manage these fractures. Stable fixation in areas of low bone quality may require the use of cortical bone strut allografts. MATERIAL AND METHODS: Cortical allograft struts were used in the treatment of 71 patients with periprosthetic fractures between a 10 year period from 1/1999 until 12/2008. 18 patients had a periprosthetic fracture around the knee implant, 52 around the hip implant and 1 in between the hip and knee prosthesis. The average follow-up time was 943 days ranging from 90 days to 3428 days. RESULTS AND CONCLUSIONS: The overall union rate was 91%. 20 patients died during the follow-up, 6 of them during the first six month after operation. 8 patients (12%) had an diagnosed infection during the follow-up time. The specific strategy chosen to periprosthetic fracture treatment should depend on the quality of the remaining bone stock, type of the implant, location and classification of the fracture and on patients related factors, such age age and comorbidities. Use of cortical bone struts is a good option in fractures associated with poor bone quality. Use of allograft strut combined with a nonlocking plate, which offers the highest stiffness known, may provide superior bio-mechanical stability compared with other methods in some situations.