Can Relative Motion Extension Splinting Provide Earlier Return to Hand Function Than a Controlled Active Motion Protocol? A Randomized Clinical Trial

Objective: Various active mobilization protocols are used after repair of extensor tendons in zone V and VI. These include relative motion extension splinting (RMES) and controlled active motion (CAM) protocols. Similar outcomes are reported for most early active mobilization protocols, however reports on RMES protocols suggest a possible earlier return to work and functional use of the affected hand. To date no published prospective trials have compared the RMES to other early active mobilization protocols. This randomized clinical trial prospectively investigated whether patients with extensor tendon repairs in zone V and VI managed with an RMES protocol would return to functional use of the hand sooner than those managed with an extensor CAM protocol. Methods: Between January 2015 and February 2016, 42 participants who had undergone extensor tendon repair in zone V and/or VI were recruited to the study. They were randomized into 2 groups: one group was treated using a CAM protocol, the other an RMES yoke-only protocol. Participants were reviewed at 4 and 8 weeks post-operatively. The primary outcome was the Sollerman Hand Function Test (SHFT) score. Secondary outcomes were days to return to work, total active motion (TAM), grip strength and questionnaires including the QuickDASH (Disabilities of Arm, Shoulder and Hand) and satisfaction. Incidence of tendon rupture was recorded. Results: Results are as follows: SHFT mean score at 4 weeks: RMES 66 (SD: 7), CAM 59 (SD: 10), (p = 0.0073), SHFT at 8 weeks RMES 76 (SD: 2), CAM 75 (SD: 5), (p = 0.63). Median days to return to work: RMES: 20 (IQR: 12, 57), CAM: 18 (IQR: 6, 55), (p = 0.77). QuickDASH 4 weeks: RMES 28.4 (SD: 14.5), CAM 40.7 (SD: 18), (p = 0.05). QuickDASH 8 weeks: RMES 11 (SD: 11), CAM 14 (SD: 13.1), (p = 0.35). TAM 4 weeks: RMES 185.9° (SD: 48.3), CAM 147.9° (SD: 41.7), (p = 0.008). TAM 8 weeks: RMES 236.4° (SD: 28.3), CAM 209.1° (SD: 37.6), (p = 0.030). Mean grip strength percentage of contralateral hand at 8 weeks: RMES 82.8% (SD: 23.7), CAM 73.8% (SD: 22.1), (p = 0.47). Mean percentage satisfaction with splint: RMES 75.9% (SD: 17.3), CAM 43% (SD: 22.2), (p < 0.0001). No tendon ruptures occurred, one RMES participant underwent tenolysis surgery. Conclusions: This is the first randomized clinical trial to prospectively compare an RMES protocol to a CAM protocol. Participants treated with an RMES protocol demonstrated better early return to functional use of the hand than those treated with a CAM protocol, and RMES participants continued to show better range of motion to CAM participants at eight weeks. RMES participants were also more satisfied with splinting than CAM participants. There was no difference in return to work timeframes, possibly due to factors outside the control of the study. No ruptures occurred in either group, complication rates were low and not significantly different between groups. This study has demonstrated that an RMES protocol provides an earlier return to hand function than a CAM protocol for the patients who have undergone extensor tendon repair in zones V and VI.