Background: Knee arthrodesis can be an effective treatment option
for relieving pain and restoring some function after the failure of a total
knee arthroplasty as the result of infection. The purpose of the present study
was to review the outcome of a staged approach for arthrodesis of the knee
with a long intramedullary nail after the failure of a total knee arthroplasty
as the result of infection.
Methods: We reviewed the results for twelve patients who underwent
knee arthrodesis after the removal of a prosthesis because of infection. The
study group included seven women and five men who had an average age of
sixty-eight years at the time of the arthrodesis. All patients were managed
with a staged protocol. Implant removal, débridement, and insertion of
antibiotic cement spacers was followed by the administration of systemic
antibiotics. Provided that clinical and laboratory data suggested eradication
of the infection, arthrodesis of the affected knee with use of a long
intramedullary nail was carried out. Clinical and laboratory evaluation and
radiographic analysis were performed after an average duration of follow-up of
4.1 years.
Results: Solid union was achieved in ten of the twelve knees. The
average time to union was 5.5 months. One patient had an above-the-knee
amputation because of recurrence of infection. In another patient, nail
breakage occurred three years following implantation. The average limb-length
discrepancy was 5.5 cm. The mean Western Ontario and McMaster Universities
Osteoarthritis Index (WOMAC) score improved from 41 to 64 points. None of the
seven patients who underwent arthrodesis with a technique involving
convex-to-concave reamers had a complication, and the average time to union
for these seven patients was shorter than that for the remaining five patients
(4.3 compared with 7.4 months).
Conclusions: We believe that obtaining large surfaces of bleeding
contact bone during arthrodesis following staged treatment of an infection at
the site of a failed total knee arthroplasty contributes to stability and
enhances bone-healing. Staged arthrodesis with use of a long intramedullary
nail and convex-to-concave preparation of bone ends provided a painless
functional gait with low complication and reoperation rates in this
challenging group of patients.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.