Amelioration by mecobalamin of subclinical carpal tunnel syndrome involving unaffected limbs in stroke patients
Authors: Kei Satoh
Jun Iwamoto
Yoshiaki Honda
Tomohiro Kanoko
Yoshihiro Sato
Journal: Journal of the Neurological Sciences (2005)
Discipline: NEUROSCIENCE & BEHAVIOR
Keywords: nonparetic side; stroke; mecobalamin; carpal tunnel syndrome; electrophysiologic indices
Affiliations: Department of Neurology, Mitate Hospital, 3237 Yugeta, Tagawa 826-0041, Japan. 

Abstract:  Our previous study showed that overuse of the nonparetic hand and wrist of the nonparetic side following stroke result in significantly more abnormal on the nonparetic side than on the hemiparetic side in terms of electrophysiologic indices of median nerve function. The purpose of this study was to evaluate the effects of the orally administered mecobalamin, an analogue of vitamin B12, for carpal tunnel syndrome (CTS) in the nonparetic side in patients following stroke. In a randomized open label and prospective study of stroke patients, 67 received of 1500 mug mecobalamin daily for 2 years, and the remaining 68 (untreated group) did not. At baseline, sensory nerve conduction velocity, motor nerve conduction velocity, sensory nerve action potentials (SNAP) at the wrist, palm-to-wrist distal sensory latency, palm-to-wrist SNAP, motor nerve conduction velocity compound motor action potentials, and distal motor latency of median nerve were significantly more abnormal on the nonparetic side than on the hemiparetic side or in controls. Before the treatment 21 patients (31%) of untreated and 20 patients (30%) of treated group met electrophysiologic criteria for CTS. Sensory impairment of the nonparetic side had lessened in the treated group. After 2 years, all electrophysiologic indices of nonparetic side were significantly improved in the treated group compared with those in the untreated group. The improvement from baseline of electrophysiologic parameters in sensory nerve in the treated group was greater than the improvement measured in motor nerve. There were no side effects. Oral mecobalamin treatment is a safe and potentially beneficial therapy for CTS in stroke patients. 

Retracted: No

PubPeer comments:
 This paper should have been retracted. This trial report was included in the systematic review that identified serious and wide-ranging problems with 33 publications of randomized trials by this group of investigators (Neurology 206:87:2391-402). 28 of the 33 trial reports have been retracted. All of the trial reports with Dr Sato as a first author have been retracted, except those in the Journal of Neurological Sciences. There is now a context of multiple ( 90) retractions of work by this group of researchers for a wide range of reasons that include fabrication, authorship misconduct, duplicate data reporting, plagiarism and unresolved concerns about data integrity J Neurol Sci and its publisher, together with all the other journals and publishers of the 33 trial reports, were notified by the editor of Neurology about the concerns with this paper in September 2016. In addition to the those already published in Neurology, concerns specific to this paper, which were sent to J Neurol Sci in May 2018, are: Ethical oversight The study was reported to have been approved by u2018each institutional ethics committeeu2019, implying more than one institution was involved. Keio University could not have been involved since Dr Iwamoto did not participate in Dr Satou2019s studies, except as an u2018honorary authoru2019, see below. Hirosaki University reported to us that this work was not approved by its Ethics committee. The other institution was Mitate Hospital, which is unlikely to have had an ethics committee - the only research said to have been approved by the Mitate Hospital committee was that by Dr Sato and colleagues, and to our knowledge none of the investigating journals and institutions has obtained documentary evidence that the committee exists. The work in question, if it was conducted, was undertaken without ethical approval and oversight. Concerns Authorship Drs Sato and Iwamoto engaged in systematic reciprocal authorship misconduct between 2002 and late 2013. Dr Iwamoto has publicly acknowledged that he did not participate in Dr Satou2019s studies (Acta Scand 2018; 2018;138:263). Drs Honda, Kanoko and Satoh were u2018honorary authorsu2019 on several papers published by Dr Sato that have now been retracted. Governance No funding support is reported for the trial and control group evaluations for a large and intensive study. The institution at which the study was carried out is not reported Implausibly similar randomized treatment groups The baseline data in the randomized groups are improbably similar. Of 22 continuous variables for which baseline data are reported in the randomized groups, 15 comparisons have P 0.6, substantially more than expected (P=0.019). For all 11 categorical variables for which baseline data are reported, P is 0.7 for the comparison between groups. , 
 On 14 June 2020 the publisher informed us that this paper was to be retracted. 9 months later, it has not been. It has been cited a total of 16 times (Scopus). Lengthy delays in publication of retraction notices are not in the best interests of readers. , 
 It is now 21 months since Elsevier communicated, via COPE, its undertaking to retract this paper. Recent requests for an update on the retraction to Elsevier, COPE, and the journal did not receive a response. The society associated with the journal, the World Federation of Neurology, responded but was unable to provide any information. ,