Revision total hip arthroplasty: the femoral side using cemented implants

Advances in surgical technique and implant technology have improved the ten-year survival after primary total hip arthroplasty (THA). Despite this, the number of revision procedures has been increasing in recent years, a trend which is predicted to continue into the future. Revision THA is a technically demanding procedure often complicated by a loss of host bone stock which may be compounded by the need to remove primary implants. Both cemented and uncemented implant designs are commonly used in the United Kingdom for primary and revision THA and much controversy still exists as to the ideal method of stem fixation. In this article we discuss revision of the femur using cemented components during revision THA. We focus on three clinical scenarios including femoral cement-in-cement revision where the primary femoral cement-bone interface remains well fixed, femoral cement-in-cement revision for peri-prosthetic femoral fractures, and femoral impaction grafting. We discuss the clinical indications, surgical techniques and clinical outcomes for each of these procedures

The Modular Universal Tumour And Revision System (MUTARS®) in endoprosthetic revision surgery

The aim of this study was to present the clinical and functional results of revision surgery after failed hip endoprostheses using the Modular Universal Tumour And Revision System (MUTARS®). Functional results of the hip endoprostheses were recorded by applying the Harris hip score. The extent of the presurgical radiological bone defect was measured according to the classification system of the German orthopaedic association (DGOOC). Indications for revision surgery on 45 patients (21 female, 24 male) were aseptic loosening (19 patients), infection (16 patients), or periprosthetic fracture (Vancouver classification B2, B3 and C, in nine patients). Revision surgery was performed after 8.6 years on average (min. 0.6; max. 14.25 years). Large defects of the proximal femur (80% medial or lateral diaphysis; 20% meta-diaphysis according to DGOOC classification) were adequately reconstructed. The average follow-up was 38.6 months. Complications occurred in eight patients: one luxation, two aseptic loosenings, and five reinfections were diagnosed. The Harris hip score (presurgical 30; postsurgical 78) showed significant improvement after revision surgery. Regarding the extent of the patients’ bone defects, good functional results were achieved. The comparatively low number of luxations and loosenings is due to the high modularity of the prosthesis with arbitrary antetorsion in the hip joint. However, high reinfection rates in mega-implants still constitute a problem and should be the subject of further studies

Impaction grafting in the femur in cementless modular revision total hip arthroplasty: a descriptive outcome analysis of 243 cases with the MRP-TITAN revision implant

<p>Abstract</p> <p>Background</p> <p>We present a descriptive and retrospective analysis of revision total hip arthroplasties (THA) using the MRP-TITAN stem (Peter Brehm, Weisendorf, GER) with distal diaphyseal fixation and metaphyseal defect augmentation. Our hypothesis was that the metaphyseal defect augmentation (Impaction Bone Grafting) improves the stem survival.</p> <p>Methods</p> <p>We retrospectively analyzed the aggregated and anonymized data of 243 femoral stem revisions. 68 patients with 70 implants (28.8%) received an allograft augmentation for metaphyseal defects; 165 patients with 173 implants (71.2%) did not, and served as controls. The mean follow-up was 4.4 ± 1.8 years (range, 2.1–9.6 years). There were no significant differences (p > 0.05) between the study and control group regarding age, body mass index (BMI), femoral defects (types I-III as described by Paprosky), and preoperative Harris Hip Score (HHS). Postoperative clinical function was evaluated using the HHS. Postoperative radiologic examination evaluated implant stability, axial implant migration, signs of implant loosening, periprosthetic radiolucencies, as well as bone regeneration and resorption.</p> <p>Results</p> <p>There were comparable rates of intraoperative and postoperative complications in the study and control groups (p > 0.05). Clinical function, expressed as the increase in the postoperative HHS over the preoperative score, showed significantly greater improvement in the group with Impaction Bone Grafting (35.6 ± 14.3 vs. 30.8 ± 15.8; p ≤ 0.05). The study group showed better outcome especially for larger defects (types II C and III as described by Paprosky) and stem diameters ≥ 17 mm. The two groups did not show significant differences in the rate of aseptic loosening (1.4% vs. 2.9%) and the rate of revisions (8.6% vs. 11%). The Kaplan-Meier survival for the MRP-TITAN stem in both groups together was 93.8% after 8.8 years. [Study group 95.7% after 8.54 years ; control group 93.1% after 8.7 years]. Radiologic evaluation showed no significant change in axial implant migration (4.3% vs. 9.3%; p = 0.19) but a significant reduction in proximal stress shielding (5.7% vs. 17.9%; p < 0.05) in the study group. Periprosthetic radiolucencies were detected in 5.7% of the study group and in 9.8% of the control group (p = 0.30). Radiolucencies in the proximal zones 1 and 7 according to Gruen occurred significantly more often in the control group without allograft augmentation (p ≤ 0.05).</p> <p>Conclusion</p> <p>We present the largest analysis of the impaction grafting technique in combination with cementless distal diaphyseal stem fixation published so far. Our data provides initial evidence of improved bone regeneration after graft augmentation of metaphyseal bone defects. The data suggests that proximal metaphyseal graft augmentation is beneficial for large metaphyseal bone defects (Paprosky types IIC and III) and stem diameters of 17 mm and above. Due to the limitations of a retrospective and descriptive study the level of evidence remains low and prospective trials should be conducted.</p