Mylène Jansen

KJD in regular care 117 6 In both cases, despite the absence of quantification of the joint space widening in clinical practice, a clear increase in joint space width is demonstrated, in previous studies clearly related to cartilage thickening using MRI and biochemical markers. 9,10,15 Complications All treatment-related complications that occurred are summarized in Table 2. Pin tract infections occurred most often and in 86% of cases were successfully treated with oral antibiotics. A combination of intravenous and oral antibiotics was necessary in 14% of pin tract infections. OPS patients had significantly more pin tract infections than RCT patients (OPS 85%; RCT 57%; p= 0.030). There was no significant difference in pin tract infections between regular care patients and any of the trial patient groups (OPS/RCT, OPS or RCT; all p> 0.1). Patients experiencing osteomyelitis (6 patients) were treated with additional surgical cleaning of pin tract wounds and a combination of intravenous (2 weeks) and oral (4 weeks) antibiotics according to a local standardized treatment protocol for osteomyelitis. Pin loosening (3 patients) or breaking (1 patient, reason unknown) was treated by tightening or refixation of the pins at either the emergency room or the outpatient clinic, while the 1 patient experiencing pin tract bleeding received a pressure bandage at the emergency room. Both deep venous thrombosis (2 patients) and pulmonary embolisms (3 patients) were treated with extra anticoagulation, which in case of a pulmonary embolism included hospitalization. For the patient experiencing a suspected compartment syndrome, the frame was immediately removed and a fasciotomy was performed, while the 1 patient who had pneumonia received intravenous antibiotics. Of patients with complications, 15 experienced them after frame removal. Ten were post- distraction infections, treated with oral antibiotics (3 patients) or a combination with intravenous antibiotics (7 patients), and 1 was a postoperative foot drop, successfully treated with an ankle-foot orthosis. The cause has been discussed previously. 14 Flexion limitation (3 patients) was treated with manipulation under anesthesia and in 1 case arthroscopic arthrolysis, while the corpus liberum (a loose piece of cartilage/bone) present in 1 patient after treatment was arthroscopically removed. The decrease in ROM shortly after distraction as observed in regular care (-26.5° (95%CI -32.0 to -21.0); p< 0.001) and the clinical trials (-20.1 (-26.6 to -13.6); p< 0.001) was largely regained within 4 months. Compared to baseline ROM, the regular care patients showed a statistically significant decrease at 4 months (-5.8 (-10.2 to -1.4); p= 0.011), but not at 12 months (-2.3 (-6.3 to 1.8); p= 0.263), as shown in Figure 3. Clinical trial patients showed no statistically significant difference at 4 months (-3.5 (-7.4 to 0.5); p= 0.085) and 12 months (+2.7 (-0.6 to 6.0); p= 0.112). When correcting for baseline ROM and distraction duration, there was a statistically significant difference between regular care and clinical trial patients for the 12-month change ( p= 0.013), but not the 4-month change ( p= 0.232).