Critical assessment of the anterolateral thigh flap donor site

The free anterolateral thigh flap (ALT) is now used as a 'workhorse flap'. The donor site morbidity is thought to be minimal, although most evidence derives from questionnaire-based studies rather than rigorous objective clinical assessment. In particular, robust quantitative data on thigh sensibility and quadriceps function is lacking. The aim of this study was to provide a comprehensive clinical assessment of donor site morbidity.

We performed a prospective study of consecutive free ALT perforator flaps performed at Salisbury Foundation Trust between March 2008 and April 2010. The donor site was assessed at six months including a questionnaire (symptoms, function), scar analysis (Vancouver Scar Scale, VSS), and evaluation of quadriceps power and lateral thigh sensibility (compared with the contralateral unoperated thigh).

One hundred ALT flaps were performed on 97 patients (mean age 46.8 years). The donor site was closed directly in 88 cases and using a split skin graft in 12 cases. At follow-up (n=68), tingling was the most common reported symptom (59%), whereas pain, itching and muscle herniation were reported infrequently. Donor site scars were mostly flat, pale and soft but widened. Pathological scarring was rare. Sensibility was reduced in donor thighs (p<0.001) and correlated with flap width but peak quadriceps contraction was similar between donor and unoperated thighs.

There was a high throughput and diverse application of ALT flap reconstructions during the study period. Reduced sensibility was common around the scar but rarely troublesome. Quadriceps function was not affected even when dissection of intramuscular perforators was required. The ALT is a versatile flap that can deliver a large skin paddle with minimal impact on thigh function.