gms | German Medical Science

Objectives/Interrogation: The gold standard treatment for a complete traumatic peripheral nerve lesion involves direct end-to-end microsurgical repair. Tension across the repair site contributes to formation of scar and the risk of neuroma formation. Conduits may be used to reduce scar tether at repair sites or to provide a supported segment of injured nerve for sutureless repair. A randomized controlled trial investigating the outcomes of digital nerve repair requires a two-stage recruitment process. This report summarises the recruitment efficiency and strategies that may result in enhanced participation.

Methods: Patients were assessed using the "ten-test" sensory evaluation following hand injury. Patients with reduced sensation in a digital nerve distribution were referred to a research nurse for consent and first stage recruitment to the CoNNECT study. Intra-operative confirmation of a complete nerve injury meeting inclusion criteria allowed second stage recruitment and randomisation. Analysis of screening data and recruitment logs from June 2017 to October 2018 enables assessment of recruitment efficiency.

Results and Conclusions: 236 patients met clinical screening criteria and 192 consented for trial recruitment (12 per month). At operation 113 patients did not meet the second stage recruitment criteria (75 patients no visible nerve injury, 20 with partial nerve injury, 8 had injuries outside of the target zone, 2 had a nerve gap requiring reconstruction with a graft, 1 proceeded to primary digit amputation and 7 patients were deemed by the operating surgeon not to fulfil the first stage eligibility criteria). 69 patients had at least one nerve injury meeting the second stage inclusion criteria. 3 patients did not proceed to randomisation due to limited operating time and 3 further patients were not randomised due to operator uncertainty regarding the trial protocol. 73 nerves in 63 patients were randomised to one of the three study arms. 1 patient has since withdrawn from the study after randomisation and completion of the procedure.

Our RCT demonstrated that only 27% of patients clinically screened participated in the study and 6 patients were missed at second stage recruitment due to time constraints or inadequate planning of theatre resources. Recruitment efficiency is 91% and retention is 98% for the CoNNECT study. Careful monitoring of recruitment efficiency highlights areas where training and resource allocation can optimise study participation.