Introduction: Extensor pollicis longus (EPL) is the most commonly injured extensor tendon in the hand. Following repair of this tendon, whilst early active motion within a volar orthosis is simple and inexpensive, it is not known whether it is more effective at regaining thumb motion than immobilisation. Methods: A prospective comparison pilot study including 20 outpatients with repaired EPL tendon lacerations in zones TIII-TV was undertaken. Participants were non-randomly allocated to either immobilisation group or early active motion. The primary outcome measure was thumb interphalangeal joint active extension-flexion. Secondary outcome measures were metacarphalangeal joint active extension-flexion, composite active thumb opposition and retropulsion, the patient-rated wrist/hand evaluation and return to work. Results: At 8 weeks, the mean between-group differences for interphalangeal joint extension (À10 ; 95% CI À1 to À19), metacarphalangeal joint extension (À12 ; 95% CI À23 to À0.4) and composite thumb retropulsion as a percentage of uninjured side (42%; 95% CI 3-81) were all clinically important. There were no other significant between-group differences at 6 or 8 weeks, and no ruptures in either group. Conclusion: This pilot comparison study indicated that early active motion has an effect on thumb interphalangeal joint extension, metacarphalangeal joint extension and composite thumb retropulsion by 8 weeks post-operatively. This study lends weight to the need for a properly conducted randomised controlled trial.