This prospective study reveals that the incidence of seroma formation after harvesting the latissimus dorsi muscle by scalpel is reasonably moderate. This incidence is lower when the resulting skin flaps are tacked to the underlying structures with resorbable sutures. In contrast, electrocautery dissection shows a significantly much higher rate of seroma formation, probably because of thermal injury of the wide fascial wound layers or the subcutaneous fat tissue. Fifty-eight patients were distributed among three groups. Within each group a specific way of latissimus dorsi muscle harvesting and donor site treatment was accomplished. The group of scalpel dissection and skin flap fixation to the underlying layers with additional tacking sutures shows the lowest rate of seroma formation (9.1%, N = 2) due to the avoidance of shearing effects. A clearly higher incidence is present in the group of scalpel dissection without tacking sutures (38.1%, N = 8), whereas seromas most frequently result after electrocautery dissection without skin flap fixation (80.0%, N = 12).