Does the distance of the fixation points to the fracture affect healing in tibial shaft fractures treated with openable distal claw intramedullary nail?

Objective: A retrospective examination was made of tibia shaft fractures treated with tibia intramedullary nail (IMN), which are designed with distal retractable claws, unlike classic imtramedullar nails. It was aimed to evaluate the effect on healing of the nail diameter and the distance between the fracture line and the proximal and distal fixation points of the IMN. Material and Method: The study included 28 patients (18 males, 10 females; mean age 43.75 (18-69) years) treated with distal retractable claw tibia IMN (Dunitech Nite Tibial IMN Oliga Med Ankara-Turkey) for a diagnosis of unilateral tibia diaphyseal fracture between January 2020 and January 2022. The midpoint of the fracture line (F), the proximal fixation point of the locking screw (S), the distal fixation point of the retractable claw (T), and the isthmus mid-point (I) were determined as reference points. The FT, ST, and IT distances, the nail diameter (ND) and isthmus diameter (ID) were measured and the FT/ST ratio was calculated. Statistical evaluations were made of the relationships between the diameter and length measurements and the visual analog scale (VAS) and radiographic union score for tibia (RUST) scores at the end of one year. Results: No statistically significant correlation was determined between the RUST and VAS scores and the diameter measurements or the distance between the proximal and distal fixation points of the IMN.Conclusion: There was no effect on the fracture healing scores of the nail diameter or the distance between the proximal and distal fixation points in tibia shaft fractures treated with a tibia nail with distal retractable claws. The nail design with retractable claws provides strong fixation and stable fracture healing. The operating time is shorter resulting in less radiation exposure.