Abstract: Objective To explore the influence of longitudinal and oblique hollow lag screw internal fixation on interphalangeal range of motion,metacarpal range of motion and complications in patients with transverse fractures of proximal phalanges.Methods Retrospective analysis was performed on 102 patients with transverse fractures of proximal phalanges admitted to department of orthopedics of our hospital from June 2021 to February 2022.According to treatment methods,the patients were divided into longitudinal group and oblique group.The longitudinal group was given longitudinal hollow lag screw internal fixation while the oblique group was treated with oblique hollow lag screw internal fixation.The baseline data of the enrolled subjects were excluded from the influence of confounding factors according to the propensity matching scoring method (caliper value=0.02),and 51 patients with comparable baseline data were obtained in each group.The surgical status (surgical time and healing time),ranges of motions of interphalangeal and metacarpal joints,excellent and good rate of hand function (total active movement,TAM) and complications at 18 months after surgery were compared between the two groups.Results All patients successfully completed the surgery,and at least 18 months of follow-up data were obtained.There was no statistical significance in the surgical time or follow-up time between the two groups (P>0.05).The healing time in oblique group(6.57±1.22)weeks,was significantly shorter than that in longitudinal group(7.82±1.54)weeks (P<0.05).At 18 months after surgery,the interphalangeal range of motion was significantly higher in oblique group(82.62±3.41)° than that in longitudinal group(77.45±7.46)° (P<0.05),but there was no statistical difference in metacarpal range of motion between the two groups (P>0.05).The excellent and good rate of hand function in oblique group (94.12%) at 18 months after surgery was significantly higher than that in longitudinal group (80.39%) (P<0.05).The incidence of complications revealed no statistical significance between oblique group (1.96%) and longitudinal group (3.92%) (P>0.05).Conclusion In the hollow lag internal screw fixation treatment of patients with transverse fractures of proximal phalanges,both longitudinal and oblique screw methods have good effects,but the oblique screw method is more beneficial to the recovery of hand function.

Key words: hollow lag screw internal fixation; transverse fractures of proximal phalanges; joint range of motion