Background. Adequate pain management is mandatory for patients' early rehabilitation and improvement of outcome after total knee arthroplasty (TKA). Conventional pain management, consisted of mainly opioids, has some adverse effects such as
Introduction and Objective. Knee osteoarthritis (KOA) is a frequent disease for which therapeutic possibilities are limited. In current recommendations, the first-line analgesic is acetaminophen. However, low efficacy of acetaminophen, frequently leads to the use of weak opioids (WO) despite their poor tolerance, especially in elderly patients. The primary objective was to compare the analgesic efficacy and safety of a new wearable transcutaneous electrical nerve stimulation (W-TENS) to weak opioids (WO) in the treatment of moderate to severe, nociceptive, chronic pain in knee osteoarthritis patients. Materials and Methods. ArthroTENS study is a phase 3, non-inferiority, multicentric, prospective, randomized, single-blinded for primary efficacy outcome, controlled, in 2-parallel groups, clinical study comparing W-TENS versus WO over a 3-month controlled period with an additional, optional, non-controlled, 3-month follow-up for patients in W-TENS group. The co-primary outcome was KOA pain intensity (PI) at month 3 and the number of adverse events (AEs) over 3 months. Results. The non-inferiority of W-TENS was demonstrated in both the PP and ITT populations. At M3, PI in PP population was 3.87 (2.12) compared to 4.66 (2.37) (delta: −0.79 (0.44); 95% CI (−1.65; 0.08)) in W-TENS and WO groups, respectively. Since the absolute value of the 95% CI of the between-treatments mean PI difference [−1.71, – 0.12] was above 0 in ITT set, the planned superiority analysis was performed, demonstrating that W-TENS was significantly superior to WO at M3 (P=0.0124). At M1 and M3, the W-TENS group reached the absolute minimal clinically important difference (MCID) for an analgesic (1.8 (2.1) and 2.1 (2.3), respectively), corresponding to a 20 mm reduction in PI (interquartile range: 15–30) on a 0–100 mm visual analogic scale – i.e. 2 points on a numerical rating scale – which equates to “much better”. Conversely, in the WO group, a 0.5 (1.8) and a 1.1 (2.1) reduction in PI were observed at M1 and M3, respectively, while a 1-point reduction in PI is required to be considered as a “slightly better” improvement. In WO group, AEs were the common systemic AEs reported with WO (nausea, constipation, drowsiness,
Background. The second generation metal-on-metal (MoM) prosthesis of the hip became a worldwide success in the 90s. However, after the placement of a MoM prosthesis the cobalt ion concentrations raise significantly. This may lead to systemic complaints and even cobalt toxicity. Methods. Sixty-one patients (26F/35M) with both an unilateral and bilateral resurfacing or large-head MoM (LHMoM) hip prosthesis were included. At last follow-up (5.77 ± 1.57 yrs) cobalt concentrations in the blood were determined by ICP-MS. Based on the known cobalt toxicity symptoms we developed a non-validated questionnaire. Analysis was done on two groups; a low cobalt concentration group and a high cobalt concentration group. We used 170 nmol/L as the upper limit of well functioning prosthesis as defined by the Dutch Orthopaedic Society (NOV). Independent samples T test and Pearson correlation coefficient were done. Results. In 61 patients, 70 prosthesis were implanted: 44 resurfacings and 26 LHMoM. Mean cobalt and chromium ion concentrations were 110 ± 138 (9 – 833) and 104 ± 138 (6 – 592) nmol/L. The low cobalt concentration group consisted of 52 patients, while the high cobalt concentration group consisted of 9 hips. With respect to the systemic complaints, the subjects in the high or low group reported no significant differences. A trend towards more complaints with visual problems (75% vs 51.9%, P = .089) and
