Parviz Ahangar - ۱ Department of Orthopedic Surgery, Faculty of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran. ۲ Trauma Research center, Department of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
Alireza Rahimnia - ۱ Department of Orthopedic Surgery, Faculty of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran. ۲ Trauma Research center, Department of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
Masoud Mokhtari - Department of Orthopedic Surgery, Faculty of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
Amirhossien Rahimnia - Department of Medicine, Tehran University of Medical Sciences, Tehran, Iran

Background: Fracture-dislocations of the proximal interphalangeal joint of fingers are believed to be challenging injuries that usually lead to residual pain and stiffness. To date, several treatment options have been applied. Dynamic traction-external fixation is a safe and easy technique offering good results in many works of literature. The dynamic mini external fixator using K-wires and mini rods provide sufficient dynamic traction and facilitate early mobilization of the injured joint. The present study was conducted to evaluate the results of a dynamic mini external fixator for the treatment of those lesions. Methods: In total, ۴۰ patients who suffered from proximal interphalangeal fracture-dislocations were treated at our institution between November ۲۰۱۷ and November ۲۰۱۹. Dynamic mini external fixator device was utilized for their treatment. Clinical and radiographic parameters were evaluated at ۲, ۴, ۶, ۱۲, and ۲۴ weeks after surgery. Results: This study included ۳۰ (۷۵%) males and ۱۰ (۲۵%) females with a mean age of ۳۸.۷±۹.۹ years. In total, ۶ (۱۵%) patients had concomitant fractures or fractures in their hands. All the fractures, including ۲۷ (۶۷.۵%) dorsal fracture-dislocations and ۱۳ (۳۲.۵%) Pilon fractures, were united without the occurrence of any malunion or major residual subluxation. One Pilon fracture needed to be realigned by reassembling the device at the second week of follow-up. Furthermore, ۳۶ (۹۰%) patients achieved full range of joint motion, and ۴ (۱۰%) patients had mild loss of motion arc. In addition, ۸ (۲۰%) patients developed mild pin site infection treated with oral antibiotics without device removal. Following six months, one (۲.۵%) patient mentioned minimal residual pain. Conclusion: The dynamic mini external fixator was found to be a safe and applicable technique to manage proximal interphalangeal fracture-dislocations. To obtain significantly accurate results, regular follow-up and accurate device care are of great necessity. Level of evidence: IV

Articular, Early ambulation and range of motion, External fixators, Finger joint, Fracture dislocation