Backgound: Metrics for movement smoothness include the number of zero-crossings on the acceleration profile (N0C), the log dimensionless jerk (LDLJ), the normalized averaged rectified jerk (NARJ) and the spectral arc length (SPARC). Sensitivity to the handedness and movement type of these four metrics was compared and correlations with other kinematic parameters were explored in healthy subjects. Methods: Thirty-two healthy participants underwent 3D upper limb motion analysis during two sets of pointing movements on each side. They performed forward- and backward-pointing movements at a self-selected speed to a target located ahead at shoulder height and at 90% arm length, with and without a three-second pause between forward and backward movements. Kinematics were collected, and smoothness metrics were computed. Results: LDLJ, NARJ and N0C found backward movements to be smoother, while SPARC found the opposite. Inter- and intra-subject coefficients of variation were lowest for SPARC. LDLJ, NARJ and N0C were correlated with each other and with movement time, unlike SPARC. Conclusion: There are major differences between smoothness metrics measured in the temporal domain (N0C, LDLJ, NARJ), which depend on movement time, and those measured in the frequency domain, the SPARC, which gave results opposite to the other metrics when comparing backward and forward movements.

Purpose: To evaluate adherence to anticholinergic therapy (AT) and clean intermittent self-catheterization (CISC) in patients with multiple sclerosis (MS) and to identify factors associated with poor adherence. Methods: This single-center study prospectively included 49 patients suffering from MS who had been prescribed AT and/or CISC. Adherence was evaluated using a self-report questionnaire. The Expanded Disability Status Scale (EDSS), Patient Global Impression of Improvement, Mini-Mental State Examination, Urinary Symptom Profile, and Hospital Anxiety and Depression (HAD) instruments were administered, and the number of daily anticholinergic pills and/or catheterizations was noted. Whether patients were receiving concomitant intradetrusor botulinum toxin injections was assessed, as were barriers to treatment, side effects, number of spontaneous micturitions, reasons for the prescription, satisfaction, and difficulties. Results: Only 38% of patients were adherent to AT. Experiencing side effects was related to nonadherence (P = 0.02). Only 29% of patients were adherent to CISC. More intense voiding dysfunction (P < 0.001), a higher frequency of CISC (P = 0.03), and a higher EDSS score (P = 0.02) were associated with better adherence. Conversely, the HAD score (P < 0.001), depression (P < 0.001), the persistence of spontaneous micturition (P < 0.001), a blocking sensation during catheterization (P = 0.04), and the need to adapt one's posture or gesture to perform catheterization (P = 0.04) were associated with poorer adherence. Conclusions: Adherence to AT and CISC was poor in patients with MS suffering from bladder dysfunction. Several factors related to nonadherence were identified in this study, and addressing these factors might help to improve treatment adherence.

Background: Tremor is the most common movement disorder, with significant functional and psychosocial consequences. Oral medications have been disappointing or limited by side effects. Surgical techniques are effective but associated with risks and adverse events. Botulinum toxin (BT) represents a promising avenue but there is still no double-blind evidence of efficacy on upper limb function. A systematic review on the effects of BT in upper-limb tremor was conducted. Methods: A systematic search of the literature was conducted up to July 2023, including the keywords “botulinum toxin” and “tremor”. All randomized controlled trials (RCTs) and open-label studies were analyzed. Independent reviewers assessed their methodological quality. Results: There were only eight published RCTs and seven published open-label studies, with relatively small sample sizes. This review suggests that BT is more effective when injections are patient-tailored, with analyses based on clinical judgement or kinematics. Subjective and objective measures frequently improve but transient weakness may occur after injections, especially if wrist or fingers extensors are targeted. A number of studies had methodological limitations. Conclusions: The authors discuss how to optimize tremor assessments and effects of BT injection. Controlled evidence is still lacking but it is suggested that distal “asymmetric” BT injections (targeting flexors/pronators while sparing extensors/supinators) and proximal injections, involving shoulder rotators when indicated, may avoid excessive weakness while optimizing functional benefit.