Cobalt toxicity in patients with hip arthroplasty is a rare complication, but it should be considered in those patients who, after a ceramic fracture, were implanted with a metal-on-polyethylene prosthesis. The complete removal of ceramic particles during revision surgery can be complicated. If the bearing surface is replaced with a metal-on-polyethylene prosthesis, these residual ceramic particles may wear down the chrome-cobalt head, producing localised metallosis. This can trigger blood metal ion levels to rise, causing systemic toxicity. Visual and auditory alterations, cognitive deterioration, hypothyroidism, neuropathy, cardiomyopathy, anorexia, fatigue, diabetes, polycythemia, and respiratory and cutaneous symptoms are some of the clinical manifestations of prosthetic cobaltism.A young patient presented with multiorgan failure secondary to cobalt toxicity after a ceramic fracture and revision with a metal-on-polyethylene prosthesis; his serum cobalt and chromium levels were 652 μg/L and 270 μg/L, respectively. The patient needed a heart transplant after presenting with cobalt-induced cardiogenic shock.In a patient with a ceramic fracture who is subjected to revision surgery with a metal-on-polyethylene bearing, it is necessary to rule out the possibility of cobalt intoxication. Serum cobalt levels > 20 μg/L are inadmissible; in these cases, surgical treatment should be considered in the short term. A wide synovectomy and replacement of components should be performed with hard friction options, preferably with a ceramic-on-ceramic prosthesis.
Poster: ECR 2015 / C-0695 / Direct magnetic resonance (MR) arthrography in femoroacetabular impingement and correlation with hip arthroscopy by: M. Crespo Rodriguez, J. C. De Lucas Villarrubia, M. A. Pastrana, S. Bartolome Garcia, A. Hualde Jubera, M. Padron; Madrid/ES
Introduction and Objectives: The registry of total hip replacements shows that 11% of THRs are performed due to hip fracture; it is the second most frequent cause for these procedures. As has been seen in different studies, THRs secondary to fracture have had a large complication rate and a lower rate of implant survival. Materials and Methods: We carried out a retrospective study of 304 THRs performed in our center between 2000 and 2002; 32 of these were due to fracture (10.5%). We assessed demographic variables, pre and postoperative function using the HSS Hip Score, surgical variables, including operation time, intra and postoperative complications, angle and inclination of the acetabulum, bleeding and postoperative pain. Results: we found no differences in HSS Hip Scores after surgery; or in the rate of intraoperative or immediate postoperative complications. In the study group we found more elderly patients, more women and a greater need for transfusions, as also a greater number of dislocations. We found no differences in the incidence of aseptic loosening, or in the incidences of periprosthetic fractures or infections. Discussion and Conclusions: Patients with a THR due to hip fracture had a poorer evolution than those that underwent THR for other reasons, due to a greater frequency of dislocation.