SCIENTIFIC ARTICLE Primary Flexor Tendon Repair in Zones 1 and 2: Early Passive Mobilization Versus Controlled Active Motion Florian Samuel Frueh, MD, Viviane Sylvie Kunz, Isaac Joseph Gravestock, MSc, Leonhard Held, PhD, Mathias Haefeli, MD, Pietro Giovanoli, MD, Maurizio Calcagni, MD Purpose To compare early passive mobilization (EPM) with controlled active motion (CAM) after flexor tendon surgery in zones 1 and 2. Methods We performed a retrospective analysis of collected data of all patients receiving primary flexor tendon repair in zones 1 and 2 from 2006 to 2011, during which time 228 patients were treated, and 191 patients with 231 injured digits were eligible for study. Exclusion criteria were replantation, finger revascularization, age younger than 16 years, rehabilitation by means other than EPM or CAM, and missing information regarding post- operative rehabilitation. This left 132 patients with 159 injured fingers for analysis. The primary endpoint was the comparison of total active motion (TAM) values 4 and 12 weeks after surgery between the EPM and the CAM protocols. The analysis of TAM measurements under the rehabilitation protocols was conducted using t-tests and further linear modeling. We defined rupture rate and the assessment of adhesion/infection as secondary endpoints. Results There was a statistically significant difference between the TAM values of the EPM and the CAM protocols 4 weeks after surgery. At 12 weeks, however, there was no significant difference between the 2 protocols. Older age and injuries with finger fractures were associated with lower TAM values. Rupture rates were 5% (CAM) and 7% (EPM), which were not statistically different. Conclusions This study showed a favorable effect of CAM protocol on TAM 4 weeks after surgery. The percent rupture rate was slightly lower in the patients with CAM than in the patients with EPM regime. Further studies are required to confirm our results and to investigate whether faster recovery of TAM is associated with shorter time out of work. (J Hand Surg Am. 2014;-:-e-. Copyright Ó 2014 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic III. Key words CAM, early active mobilization, flexor tendon repair, Kleinert protocol, zone 2. F LEXOR TENDON INJURIES IN ZONE 2 are common, and despite abundant data about surgical app- roach, rehabilitation protocols are still a current topic of debate. Established rehabilitation regimens of flexor tendon repair are immobilization, early passive mobilization (EPM) and controlled active motion (CAM). The CAM protocol was described by Small et al. 1e3 Whereas immobilization is reasonable in From the Division of Plastic Surgery and Hand Surgery, University Hospital Zurich; and the Division of Biostatistics, Institute for Social and Preventive Medicine, University of Zurich, Zurich, Switzerland. Received for publication October 23, 2013; accepted in revised form March 20, 2014. The authors thank all of the Swiss hand therapists who contributed to this study and Christine Meier and the Hand Therapy Team of the University Hospital Zurich for excellent postoperative rehabilitation. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Florian Samuel Frueh, MD, Division of Plastic Surgery and Hand Surgery, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland; e-mail: florian.frueh@usz.ch. 0363-5023/14/---0001$36.00/0 http://dx.doi.org/10.1016/j.jhsa.2014.03.025 Ó 2014 ASSH r Published by Elsevier, Inc. All rights reserved. r 1