Patient-oriented and performance-based outcomes after knee autologous chondrocyte implantation: A timeline for the first year of recovery.
Howard JS, Mattacola CG, Mullineaux DR, English RA and Lattermann C. J Sport Rehabil. 2014 [Epub Ahead of Print].http://dx.doi.org/10.1123/jsr.2013-0094
Take Home Message: Following autologous chondrocyte implantation (ACI), performance based and patient-reported outcomes can be valuable for measuring success. Patient-reported outcomes were better at all post-operative time points while performance-based measurements decreased for the first 6 months following ACI.
The success of autologous chondrocyte implantation (ACI), a common treatment for symptomatic articular cartilage defects, is normally measured through patient-reported outcomes. Despite this, performance-based metrics could also be used yet no one has recorded the timeline for recovery with patient-reported or performance-based measurements. A better understanding of the recovery timeline for both types of outcomes could help us optimize our rehab protocols and educate our patients about their anticipated recovery. Therefore, Howard and colleagues assessed performances-based and patient-reported changes in knee function over 1 year after ACI. Fifty patients participated in the study (31 male, on average 35 years of age with 1.5 treated cartilage defects). One surgeon performed all of the ACI procedures, which included 24 patellofemoral joints and 26 tibiofemoral joints. Some patients also had other procedures performed on their knee (e.g., 4 high tibial osteotomies, 2 meniscal transplantation). All patients completed a standardized rehabilitation program. Patient-reported outcome measures assessed general physical health (Short Form-36 PCS) and knee-specific symptoms and function (WOMAC, IKDC, and Lysholm scale). Performance-based assessments were walk-across, weight-bearing squat, sit-to-stand, step-up/over, and lunge. All measurements took place before ACI and at 3, 6, and 12 months post-surgery. Data for 39 patients was available at 1 year post-surgery. Compared with prior to surgery, patient-reported outcome scores showed improvement at 3 months post-surgery and continued to improve up to 12 months post-surgery. In contrast, performance-based measurements decreased at 3 and 6 months post-surgery (for example, increased asymmetry of weight distribution when squatting, longer performance times for stepping activities). The patients’ performed functional activities better at 12 months but these improvements were often not back to previously reported norms.
ACI is becoming more common and these results should help clinicians educate patients about what to expect after an ACI procedure. Firstly, the researchers showed that using a combination of performance-based and patient-reported outcomes can offer clinicians 2 different perspectives of a patient. Having both types of measurements could be particularly helpful when the patient reports feeling good and wants to return to play but their performance on functional tasks show that they are not ready. Further, the researchers were able to develop a 12-month timeline for recovery following ACI. This provides clinicians with yet another tool to assess patient progress. While this can be extremely useful to those clinicians who oversee ACI patients, there were 2 major limitations of this current study that should be brought to light. Firstly, the patient population of this study was small and lacked diversity. This in turn limits the applicability of the recommended timeline for treatment to all ACI patients. Secondly, the current study’s follow up period was relatively short and should seek to better understand the outcomes of the entire rehabilitation process and not just the 1st year. While more research is completed, the current study’s recommendations give clinicians the best overall understanding of the ACI rehabilitation process to date. It also is a great example of why we need to assess patient-reported and performance-based outcomes. This can help inform our treatment strategy and help us educate the patient.
Questions for Discussion: When you assess a patient during a rehab program do you use patient-reported and performance-based outcome measures? Have you found that asking a patient to perform a functional assessment helps them realize their actual limitations or improvements?
Written by: Kyle Harris
Reviewed by: Jeffrey Driban
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