A retrospective analysis of controlled active motion (CAM) versus modified Kleinert/Duran (modKD) rehabilitation protocol in flexor tendon repair (zones I and II) in a single center

INTRODUCTION: The aim of this study was to analyze primary flexor tendon repair results in zones I and II, comparing the rupture rate and clinical outcomes of the controlled active motion (CAM) protocol with the modified Kleinert/Duran (mKD) protocol. MATERIALS AND METHODS: Patients who underwent surgery with traumatic flexor tendon lacerations in zones I and II were divided in three groups according to the type of rehabilitation protocol and period of management: group 1 included patients who underwent CAM rehabilitation protocol with six-strand Lim and Tsai suture after May 2014. Group 2 and 3 included patients treated by six-strand Lim Tsai suture followed by a modified Kleinert/Duran (modK/D) protocol with additional place and hold exercises between 2003 and 2005 (group 2) and between 2011 and 2013 (group 3). RESULTS: Rupture rate was 4.7% at 12 weeks in group 1 (3/63 flexor tendon repairs) compared to 2% (1/51 flexor tendon repairs) in group 2 and 8% in group 3 (7/86 flexor tendon repairs). The grip strength at 12 weeks was significantly better in group 2 compared to the group 1 (35 kg/25 kg, p = 0.006). The TAM in group 1 [113° (30–175°)] was significantly worse (p < 0.001) than the TAM in group 2 [141° (90–195°)] but with similar extension deficits in both groups. The assessment of range of motion by the original Strickland classification system resulted in 20% excellent and 15% good outcomes in the CAM group 1 compared with 42% and 36% in the modK/D group 2. Subanalysis demonstrated improvement of good/excellent results according to Strickland from 45% at 3 months to 63.6% after 6-month follow-up in the CAM group. CONCLUSION: The gut feeling that lead to change in our rehabilitation protocol could be explained by the heterogenous bias. A precise outcome analysis of group 1 could underline that in patients with complex hand trauma, nerve reconstruction, oedema or early extension deficit, an even more intensive and individual rehabilitation has to be performed to achieve better TAM at 6 or 12 weeks. Our study explicitly demonstrated a significant better outcome in the modK/D group compared to CAM group. This monocenter study is limited by its retrospective nature and the low number of patients.