Study: Preoperative anterior or lateral pain is not a contraindication for medial UKA

The researchers compared patients with anterior, generalized or lateral pain vs. medial pain and found no differences between groups in functional outcome scores.

Issue: February 2013

MANCHESTER — The location of patients’ preoperative pain did not predict functional short-term outcomes of unicompartmental knee arthroplasty and should not be used as a surgical indication, according to researchers from the United Kingdom.

“Preoperative pain location has no effect on outcomes following Oxford unicompartmental knee arthroplasty [Biomet Inc,; Warsaw, Indiana],” Alex D. Liddle, MBBS, MRCS, of the University of Oxford’s Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, said during his presentation at the British Orthopaedic Association Congress.

Location of pain

Liddle noted that although some study authors suggest that purely medial pain is a prerequisite for unicompartmental knee arthroplasty (UKA), others highlight good outcomes with the procedure in patients with severe, symptomatic osteoarthritis regardless of pain location.

Alex D. Liddle

To determine whether preoperative pain location had any bearing on the outcomes of UKA, Liddle and colleagues conducted a prospective cohort study of 308 patients (406 knees) undergoing medial UKA using the Oxford implant. The investigators interviewed each patient preoperatively to determine the location of pain. The minimum follow-up was 1 year, but 132 patients reached 5-year follow-up. The investigators measured functional outcomes preoperatively, and at 1-year and 5-years postoperatively.

Comparisons

The researchers found 204 patients had pain isolated to the medial compartment, 77 patients had anterior knee pain, 25 patients had isolated anterior knee pain and 40 patients experienced generalized pain.

“As you would expect, patients had improved significantly at one year compared to preoperatively, and this was maintained at 5 years,” Liddle said. “At 1 year, there was no difference between the groups, and this was again maintained at 5 years.”

The authors conducted two additional analyses in the study. One analysis compared patients with anterior pain vs. those without and the other analysis compared patients with purely medial knee pain to those with generalized, lateral or anterior knee pain. The investigators discovered no significant differences in functional scores between the groups in both analyses.

“We conclude that localized medial pain should not be a pre-requisite to UKA, and that the procedure may be performed in patients with generalized or anterior knee pain,” the authors wrote in their abstract. – by Renee Blisard Buddle

Reference:

Liddle AD. Paper #66. Presented at: British Orthopaedic Association Congress; Sept. 11-14, 2012; Manchester.

For more information:

Alex D. Liddle, MBBS, MRCS, can be reached at the Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), Nuffield Orthopaedic Centre, University of Oxford, Windmill Rd., Headington, Oxford OX3 7YD, UK; email: alexander.liddle@ndorms.ox.ac.uk.
Disclosure: NDORMS receives institutional support from Biomet Inc. Liddle has no personal conflicts of interest.