Spontaneous distal migration of Kuntscher intramedullary nail into leg from malunited distal femur fracture: A rare case report

Abstract

Kuntscher cloverleaf nail, also called as K-nail, is an intramedullary nail (IMN), made from stainless steel with a slot along the longitudinal axis. It is used in fixation of short oblique, simple transverse, Winquist- I and II comminuted fractures of femur. This was a case in which the Kuntscher nail spontaneously migrated distally, and was extruded completely from the femur into the leg along the posterior aspect till the ankle with the most probable cause being malunion of an oblique distal femur fracture. There were no recent reports on this type of distal migration till date. A 72-year-old male, who is working as farmer in a rural area, came to our institution with pain and swelling on & off around the left ankle for last two months during May 2022. Local examination of left lower limb revealed that there was swelling around the left ankle. There was a palpable hard metallic object posterior to the left medial malleolus. There is a single well healed surgical scar of length 10 cms on the lateral aspect of left distal thigh. Radiological workup was done accordingly. Final diagnosis was – Postoperative spontaneous migration of Kuntscher nail into the leg from a malunited fracture of lower 1/3 of left femur. Treatment plan was implant removal. After implant removal, the patient was discharged in a stable condition and follow-up till 6 months revealed no complaints around the ankle or knee joints. Distal migration of K-nail across the knee joint after femur diaphyseal fracture fixation is a rare and preventable complication. It is recommended that K-nails should be routinely removed as soon as radiological union and consolidation of the fracture is confirmed, to avoid rare postoperative complication of distal migration of the K-nail.