Controversial Topics in Total Knee Arthroplasty: A 5-Year Update (Part 1)

This review article examines updates to the literature during the past 5 years on numerous topics related to total knee arthroplasty which were felt to have ongoing controversy. These include the use of peripheral nerve blocks and local infiltrative analgesia, intrathecal morphine, patellar resurfacing, and bearing designs.

For each individual topic, a literature search was conducted on several databases with emphasis on studies that were published in the past 5 years. Preference was given to meta-analyses and randomized controlled trials.

Multimodal periarticular injections may provide an equally effective analgesic effect to peripheral nerve blocks, but are also muscle sparing and less invasive. The use of intrathecal morphine in addition to periarticular injections is less desirable given the potential side effects, associated cost, and lack of clear benefit intrathecal morphine beyond the 6- to 12-hour postoperative period. Patellar resurfacing was associated with a lower rate of revision surgery, similar or potentially improved satisfaction and functional outcomes, and no increased risk of complications compared with nonresurfacing. There are no clear or notable differences between cruciate-retaining and posterior-stabilized total knee designs in terms of clinical outcomes and survivorship. Medial pivot designs theoretically recreate more normal knee kinematics compared with cruciate-retaining or posterior-stabilized designs, although superiority has not yet been clearly demonstrated and additional long-term data is necessary, particularly for survivorship.

By analyzing the results of the aforementioned studies, surgeons can implement the most up-to-date evidence-based care when doing total knee arthroplasty surgery. However, many of these selected topics continue to have a component of ongoing controversy with no definitive conclusions developed in recent literature.