Functional and radiological outcome of floating knee injury in adults - A prospective study of 42 cases

Floating knee injuries (FKI) are high-energy trauma leading to a flail knee joint, often complicated with other life-threatening injuries to the head, chest, or abdomen. The mortality and amputation rates for FKI have reduced due to better resuscitation protocols and expertise, better anaesthesia and improved quality and armamentarium of implants. This study was aimed to assess the functional outcome with the standard Karlstrom and Olerud criteria and radiological outcomes of FKI, along with special emphasis on activities like sitting cross-legged and squatting in our population. This is a prospective study of 42 patients with FKI with mean age of 36.4 years (Range 24–69 years). The fractures were classified into 6 groups – Type I, Type IIA, Type IIB, Type IIC (as described by Fraser) and Type IIIA and Type IIIB (as described by Ran). Patients were followed up with clinically and radiologically at 6 weeks, 12 weeks, 6 months and 12 months to assess the fracture healing or any complications. At the end of 12 months the function was graded by the Karlstrom and Olerud criteria with additional emphasis on patient’s ability to sit cross-legged and squat. 40 out of the 42 femur fractures had united at one year follow-up. Two patients with diaphyseal fractures had atrophic non-union requiring a second surgery. Functional evaluation using the Karlstrom Olerud Criteria showed 14 patients (33%) had Excellent result, 16 patients (38%) Good result, 10 patients (24%) Acceptable result and 2 patients (5%) had a Poor result. 14 patients (33%) were able to sit cross-legged and squat. Judicious management of the soft tissue injury, prompt stable fixation and early mobilization with a multi-disciplinary team approach are the pillars in management of FKI to obtain excellent results. Despite good functional outcomes day-to-day functions like sitting cross-legged and squatting are lost in more than half of the patients.