Relatively High Complication and Revision rates of the Mayo^® Metaphysical Conservative Femoral Stem in Young Patients

The Mayo^® conservative hip is a wedge-shaped implant designed to transfer loads proximally, reduce femoral destruction, and enable the preservation of bone stock in the proximal femur. This makes it a potentially preferred prosthesis for active non-elderly patients who may require additional surgeries in the future.

This retrospective case study analyzed the outcome of consecutive patients who underwent total hip replacements (THRs) with the Mayo^® device between 5/2001-2/2013. All patients underwent clinical assessment, radiological evaluation for the presence and development of radiolucent lines, and functional assessment (numeral analog scale, Harris Hip Score and SF-12 questionnaires).

Ninety-five hips (79 patients, 40 males) were available for analysis. The patients’ mean age was 43 years (range, 18 to 64), and the mean follow-up was 97 months (range, 26.9 to 166). The postoperative clinical assessments and functional questionnaires revealed significant improvements. Sixteen patients (16.8%) had 18 orthopedic complications, the most common of which were an intraoperative femoral fracture and implant dislocation requiring revision surgeries in ten. Radiological analysis revealed evidence of femoral remodeling in 64 (67.4%) implants, spot welds (neocortex) in 35 (36.8%), and osteolysis in three (3.2%).

These results suggest that the Mayo^® femoral implant has an unacceptable complication rate for non-elderly patients.

KEY WORDS: Mayo® metaphysical, conservative femoral stem, revision, complication