Results with Kudo elbow prostheses in non-traumatic indications : a study of 36 cases

With a mean follow-up of 62 months, we reviewed 13 Kudo type 4 and 23 Kudo type 5 elbow prostheses implanted for non-traumatic indications in 30 patients. Clinical results were assessed with the Mayo Clinic Performance Index (MCPI) taking into account pain, mobility, stability and daily activities. Postoperatively, pain disappeared or decreased, ulnar nerve dysfunction was improved and the functional status was significantly improved. The average range of motion increased by 7.8 degrees in extension and by 11.5 degrees in flexion; pronation and supination remained unchanged. Clinically, 89% of patients scored poorly on the MCPI preoperatively, whereas 61% had excellent or good scores postoperatively. Twenty-two patients out of 30 were satisfied. There were two early prosthetic dislocations, and prosthetic instability, assessed clinically, was found in 6 cases (17%). The rate of loosening was 28% (10/36) and seven elbows were revised. Metallosis, loosening and instability were significantly correlated. The survival rate of 82% at 54 months (SD = 7) is lower than that reported for non-constrained and semi-constrained prostheses in the literature.