Authors: Liv Schöllhammer, MD, Frederik Gulmark Hansen, med.stud. and Magnus Balslev Avnstorp, MD
Transposition flaps are flaps designed with a linear axis that are pivoted or transposed over a segment of intervening tissue into the primary defect.
- One border or the base of the flap must be contiguous with the primary defect
- The flap is transposed around the pivotal point the base of the flap this creates a Standing cutaneous deformity
- The standing cutaneous deformity increases the further the flap is pivoted and as a consequence the length of the flap decreases, see fig 2
- The greatest wound tension is at the closure site of the secondary defect
- The flap can be single lobed, bilobed, or trilobed, allowing for recruitment of tissue increasingly remote from the primary defect
- Most have random pattern or axial blood supply
Also known as Limberg flap or simply L-flap.
- The classic design of the flap is a four-sided parallelogram of the primary defect. Each side with equal length and tip angles of 60°and 120°. See fig 3
- There are four alternative flap designs to each defect. Which design to choose depends on adjacent skin laxity and anatomical features. See fig 3
- Can be designed bilateral
- There are several modification described so the flap will fit not only a rhomboic primary defect for example Dufourmentel and Webster
Illustrations: Christian Kaare Paaskesen, med.stud.