Mylène Jansen

Two-year results of KJD compared with HTO and TKA 73 4 JSW. For both JSW improvement and clinical benefit, KJD was shown to be non-inferior to HTO. TKA showed better clinical efficacy at 2 years than KJD for the primary and most additional outcome measures, but at the expense of the native knee joint. Difference in clinical efficacy between the treatment arms in both trials was not clinically relevant and far below the 15 points on the WOMAC scale. Despite the primary outcome not being clinically significantly different between KJD and TKA, the TKA group did show a general better response in most other clinical outcome parameters than the KJD TKA group. While KJD could be considered an alternative to HTO, KJD is not meant to replace TKA, but to postpone a primary TKA and with that potentially prevent complex and costly revision surgery later in life. In patients where TKA has been performed after KJD, there were no complications, and similar beneficial outcomes were reported as TKA recipients that did not have prior KJD treatment. 17 A health technology assessment has demonstrated that a treatment strategy starting with KJD for severe conservative treatment resistant knee OA has a large potential for being a cost-effective intervention, especially for the relatively young patient. 18 It should be noted that JSW measurements on radiographs depict the distance between bone ends, not actual cartilage thickness. Although in all cases weight-bearing radiographs were made, in case of HTO, opening of the joint space due to the correction 19 might have resulted in an overestimation of the observed JSW at the medial compartment not representing actual cartilage thickness. Looking at the change in clinical outcome for all groups, almost all parameters are significantly increased (clinical, structural, and biochemical benefit) from baseline values. Data imputation of missing clinical data (including of those lost to follow-up) did not change significance of results or conclusions. In addition to adverse effects as reported for these surgical treatments, KJD distraction resulted in pin tract infections in half of the patients. However, this is not different from pin tract infections in case of other treatments using external fixation devices. 20,21 While the amount of patients experiencing pin tract infections was lower than in previous KJD studies, as a result of an improved wound care protocol, it still determines a major burden for patients during treatment. Although all infections were successfully treated with antibiotics (mostly orally), there remains a risk for later prosthetic surgery. However, it has been reported that TKA performed within 5 years after KJD, did not result in any peri-surgical complications or prosthetic joint infections, with similar clinical benefit in those that had received KJD before TKA as compared to those that had not received a KJD before TKA. 17 While these are data from the first 2 independent RCTs comparing 2-year follow-up of KJD