MIS Oxford Knee approach as effective as medial parapatellar technique, surgeon says

Investigators saw no significant differences in results between the two UKA approaches.

Implanting the Oxford Knee using a minimally invasive surgical approach during unicompartmental knee arthroplasty appears to be as effective as the standard medial parapatellar approach, according to a study by British surgeons.

Howard Cottam, MRCS, and colleagues recruited and randomly assigned 100 patients to undergo unicompartmental knee arthroplasty (UKA) performed with either surgical approach. Patients in the first group underwent a standard technique involving longitudinal skin incisions and patellar dislocation. The second group underwent UKA using the minimally invasive approach.

Cottam presented the study results at the British Orthopaedic Association Annual Congress in Glasgow, Scotland.

The investigators found no significant differences in function between the two groups, assessed using American Knee Society Scores, the Oxford Knee questionnaire and clinical examinations performed at 6 weeks, 6 months and 1 year postop.

Cottam said he and his colleagues were unable to cite a "striking" advantage for one approach over the other, but they believe that the less invasive approach to UKA will allow patients to be discharged more quickly without compromising the patient's long-term results.

"Our results [for our measured parameters] demonstrate that there is no significant difference in outcome for the two approaches," Cottam told Orthopedics Today. "This suggests that the minimally invasive approach to the Oxford Knee is a safe approach, upon which an accelerated discharged program may be based."

"We haven't rapidly discharged our patients. Rather, we are introducing an accelerated discharge program, which will be based upon the minimally invasive surgical approach. Surgery, however, is only one facet to an accelerated discharge program," Cottam said, noting that the procedure as well as the implant position should not be compromised merely for the sake of an accelerated discharge.

For more information:
Cottam H, Jackson M, Butler-Manuel A, Apthorp H. A prospective randomized trial comparing minimal invasive and standard parapatellar approaches for unicompartmental arthroplasty. Presented at the British Orthopaedic Association Annual Congress. Sept. 27-29, 2006. Glasgow.
Howard Cottam, MRCS, specialist registrar of trauma and orthopaedics, The Conquest Orthopaedic Research Unit, Conquest Hospital, The Ridge, St. Leonards-on-Sea, East Sussex, TN37 7RD, England; +44-774-763-0509; howie@doctors.org.uk.