Objective: The aim of this study was to compare anatomic and functional improvements in zone II and zone V flexor tendon injuries and to determine the effect of injury level on disability.
Design: Seventeen patients (53 digits) with zone V and 14 patients (25 digits) with repaired zone II flexor tendon injuries were enrolled in this study. All patients were treated with Modified Kleinert protocol and followed up for a median of 60 mos. The anatomic improvement was assessed by total active motion scoring system of the American Society for Surgery of the Hand. Quick Disability of the Arm, Shoulder, and Hand (Quick DASH) questionnaire and the grip strength value were used for the evaluation of functional improvement.
Results: Two groups were similar with respect to age (P = 0.147), sex (P = 0.889), type of repair (P = 0.453), and follow-up period (P = 0.499). According to total active motion scoring system, good to excellent results (75%-100% of the normal total active motion value) were achieved in 52% of the digits with zone II and 83% of digits with zone V flexor tendon injuries (P = 0.004). The recovery in the grip strength, in comparison with the uninjured hand, has been found to be 71% and 53% in zone II and zone V injuries, respectively (P = 0.112). There was no difference between Quick DASH index scores of two groups (P = 0.721). The grip strength percentage (r = -0.435; P = 0.014) and total active motion recovery results (r = -0.541; P = 0.002) of the patients were moderately correlated with Quick DASH scores.
Conclusions: Early passive mobilization in patients with zone V injuries resulted in higher percentage of good to excellent results when compared with zone II injuries. However, this does not translate into recovery in grip strength and disability. This study suggests that although the level of the injury is an important factor for the anatomic improvement, it may not be the predictor of functional improvement.