Alpern 2005.

Methods	A randomised single‐blinded trial comparing transthecal metacarpal block to traditional digital block for the anaesthesia of finger injuries undergoing treatment in the paediatric emergency department. Trial registered with clinicaltrials.gov in August 2005. Enrolment commenced July 2005. Trial completed August 2007.
Participants	Children's Hospital of Philadelphia, Philadelphia, PA, USA. Inclusion criteria were participants under 18 years of age, weighing greater than 10 kg, with finger injuries or infections requiring digital regional anaesthesia but not general anaesthesia; English speaking. Intended recruitment size 92 participants.
Interventions	Transthecal metacarpal block versus traditional ring block
Outcomes	Success of ring block; complications associated with block; pain experienced with the block; repairing physician satisfaction with the procedure.
Notes	This trial was registered in 2005 and was seemingly completed in 2007; however, we could not find any published report of its results. We contacted the registered author directly via email who indicated that the trial manuscript is currently under revision for publication.