Research Summary

Incidence of bicompartmental osteoarthritis in patients undergoing total and unicompartmental knee arthroplasty

Heekin, R. D. and Fokin, A. A. (2014) J. Knee Surg. 27(1): 77–82. doi: 10.1055/s-0033-1349401.

Key Findings



of knee arthroplasty patients had osteoarthritis in all three compartments.



of knee arthroplasty patients had osteoarthritis in two compartments.



of knee arthroplasty patients had osteoarthritis in one compartment.

To determine the incidence of patients qualifying for potential bone preserving bicompartmental knee arthroplasty, the knee compartments of 259 knee replacement patients were evaluated for bicompartmental osteoarthritis (OA). Knees were assessed using radiography, preoperative cruciate ligaments assessments, and intraoperative cartilage grading. The study found that over half of the patients had tricompartmental OA, while approximately a third had bicompartmental OA. Only 4% of the knee arthroplasty patients had unicompartmental OA. The study also found that patients above 65 years were more likely to have multicompartmental OA compared to younger patients.

Relevance to Spring Loaded Braces

This study is among the few publications that provide a picture of compartmental distribution among knee OA patients. Understanding this distribution is not only of interest for determining the percentage of potential candidates for bicompartmental knee arthroplasty, but also for determining the number of Spring Loaded candidates among knee OA patients.

Spring Loaded bracing, like bicompartmental knee arthroplasty, may be a viable alternative to or an intermediate treatment before more invasive interventions. Most braces on the market for knee OA only address unicompartmental tibiofemoral, leaving many patients with different OA patterns with fewer non-surgical treatment options. As a brace that can substantially reduce load across all three compartments of the knee1– Budarick, A.R. et al. (2020). J. Biomech. Eng. 142(1)
– McGibbon, C.A. et al. 2020. Front. Bioeng. Biotech. doi:10.3389/fbioe.2020.604860
, Spring Loaded bracing is a conservative option that may address the many cases of multicompartmental OA among patients who may otherwise have to consider more invasive treatments.

Multiple Forces Reduced

Each TCO brace model significantly reduced PF, TF, PC ligament, PT and QT forces during a deep knee bend test.

Reduced Joint Load

Each TCO brace model significantly reduced knee joint loads by at least 32% when compared to the non-braced condition.

Replicates & Extends Previous Research

Results corroborate the knee joint offloading capabilities of a TCO, as demonstrated in a previous study (Budarick et al. 2020).

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