The double floating extremity phenomenon: case studies and evidence-based perspectives.

BACKGROUND

The "double floating extremity" phenomenon, characterized by simultaneous ipsilateral floating hip and floating knee injuries, is an extremely rare and complex orthopaedic condition. It often results from high-velocity trauma and is associated with significant systemic injuries, posing unique challenges in management due to a lack of standardized treatment protocols.

METHODS

This study reviews thirteen cases of double floating extremities, analysing clinical outcomes, management strategies, and functional recovery. We assessed functional outcome using KFS (knee function score), KSS (knee society score), and Majeed score, Merle d'Aubigné score, LEFS (lower extremity function score) scores at follow-up of 3 months, 6 months and at/more than 1 year.

RESULTS

Of thirteen patients, eleven demonstrated good-to-excellent functional outcomes at long-term follow-up (≥ 12 months), with mean Merle d'Aubigné score 15.36 (range 14-17 with SD-0.96) and mean LEFS score 65.27(range 50-74 with SD: 7.01). The mean injury severity score (ISS) for this study was 22.5 (range 10-50 with SD: 12.4). Both patients with Common Peroneal Nerve CPN palsy achieved full dorsiflexion recovery. Two patients succumbed to systemic complications, highlighting the severity of associated injuries. Early femur and tibia fixation followed by delayed pelvic fixation emerged as a practical approach to minimize systemic complications and optimize outcomes.

CONCLUSION

Double floating extremity injuries are rare but severe, requiring a systematic phased approach with staged fixation and multidisciplinary care. Incorporating injury severity score provides objective quantification of systemic injury burden. Staged fixation strategies tailored to the patient's systemic condition can improve functional outcomes. However, the scarcity of the literature and variability in treatment methodologies underscore the need for further studies to establish standardized protocols.