Free fillet flap: Outcomes in emergency microsurgical reconstruction of upper and lower limb

Despite its infrequency, 'spare-part surgery' represents a reconstructive strategy that uses segments of amputated limbs as donor tissue to preserve function in other injured anatomical regions. The purpose of this study was to review our 14-year experience in emergency microsurgical reconstruction of traumatised limbs using free fillet flaps obtained from non-salvageable amputated parts.

A retrospective observational study was conducted on patients who underwent urgent free fillet flap transfer for upper or lower limb reconstruction between 2007 and 2021. The characteristics and levels of injury, as well as the flap designs, functional outcomes and complications were documented.

A series of eight clinical cases is presented. One osteo-tendino-cutaneous and seven fasciocutaneous flaps were filleted from non-replantable amputated limbs for free transfer. Stable coverage of the dorsal aspect of the hand and fingers was achieved in three patients, and limb shortening was avoided in five patients. An open thumb fracture with bone defect, three below-knee stumps and one trans-metatarsal level were preserved. The mean Quick-Disabilities of the Arm, Shoulder and Hand score for upper limb reconstructions was 16.75 points. In all the cases of lower limb reconstruction, the nerves were repaired, resulting in a protective sensitivity (S3 level) with no pressure ulcer development during the follow-up period. All patients were able to return to normal prosthetic ambulation with a mean Amputee Mobility Predictor Pro score of 45 points. Two haematomas, one surgical wound dehiscence and two immediate revisions of venous anastomoses were registered.

The microvascular filleted flap demonstrated versatility in the emergency reconstruction of complex limb injuries, providing stable coverage and optimising limb length preservation within a single major surgical procedure, while eliminating morbidity from any other uninjured donor site.