Mylène Jansen

Systematic review and meta-analysis of KJD as treatment for OA 21 2 Introduction Knee osteoarthritis (OA) is a high incident joint disease with total knee arthroplasty (TKA) as final surgical option. 1 While TKA is considered cost-effective, reduces pain and improves function, the prosthesis’ limited lifespan brings a greater risk of a future revision when TKA is performed in younger (<65 years) patients. 2 As such, joint-preserving treatment is desirable for younger knee OA patients, to postpone TKA and reduce the chance of costly and less successful revision surgery. 3 When OA is limited to 1 side of the joint because of varus or valgus deviation, high tibial osteotomy (HTO) or distal femur osteotomy (DFO) is an option. These treatments have been applied in regular care for a long time and have been evaluated extensively. 4–7 Unicompartmental knee arthroplasty is an option in unilateral OA as well. A newer joint-preserving treatment for knee OA is knee joint distraction (KJD). Distraction is a surgical treatment where 2 bony ends of a joint are temporarily separated by an external frame, fixed to the bones with bone pins. 8 It has shown progressive and sustained pain reduction, function improvement, and an increased radiographic joint space width (JSW) in patients with ankle OA. 9–11 Following these promising results, multiple studies have investigated distraction of the knee joint. Successful KJD treatment could improve patients’ benefit, with reduced health costs for hospitals and society. 3 KJD might fill a gap in the treatment options for young patients with severe knee OA. 12 Before further implementation in regular care is justified based on the limited number of small studies, a meta-analysis is of value to give a more comprehensive overview of the current evidence for KJD as a possible treatment option. The goal of this systematic review and meta-analysis is to evaluate short- and long-term clinical benefit and tissue structure changes after KJD treatment for knee OA. Methods The review protocol is based on a protocol of Goh et al. for performing a systematic review about knee joint distraction, registered in PROSPERO (CRD42018087032). The PRISMA guidelines for systematic reviews and meta-analyses were followed. Sources and search terms On July 8 2019, MEDLINE, EMBASE and Web of Science were searched for relevant articles. Search terms were (osteoarthritis OR arthritis OR cartilage OR osteochondral OR degenerative joint disease) AND distraction AND (knee OR tibiofemoral OR tibiofibular), and were applied on title and abstract and, in Web of Science, Keywords+.