After accidents, tumour surgery or with chronic wounds, tissue defects sometimes arise that cannot be reliably closed either by direct suture or by a skin graft. This is when a flap is used: tissue that is supplied by its own blood vessels and can therefore permanently cover exposed bone, tendons or implants.
What distinguishes a flap from a graft?
A skin graft is completely detached and must first re-establish a blood supply at its new site. It therefore needs a well-vascularised wound bed. A flap, by contrast, remains connected to the body via a vascular pedicle or is connected microsurgically to new vessels. It thus brings its own blood supply with it – a decisive advantage for difficult wounds.
Classification by tissue composition
- Cutaneous flap: skin and subcutaneous fat.
- Fasciocutaneous flap: additionally includes the underlying muscle fascia, which improves the blood supply.
- Muscle or myocutaneous flap: includes muscle, with or without a skin island – suitable for filling cavities and providing a good blood supply to infected areas.
- Osteocutaneous or osteomyocutaneous flap: additionally includes bone, for example for reconstruction of the lower jaw.
Classification by distance from the defect
- Local flap: directly adjacent tissue.
- Regional flap: from the neighbouring region, with an intact vascular pedicle.
- Distant flap: from a distant region of the body, formerly often transferred in several stages.
- Free flap: completely detached and connected microsurgically to vessels in the defect area – now the standard for large and complex reconstructions.
Typical local flaps
- Advancement flap: skin is advanced in a straight line into the defect, for example as a V-Y plasty on fingertips or in the face.
- Rotation flap: a semicircular flap is rotated about a pivot point into the defect.
- Transposition flap: a flap is moved over adjacent skin into the defect; the donor site is closed directly.
- Bilobed flap: a double transposition, particularly proven for defects on the nose, where the skin has little stretch.
- Z-plasty: two triangular flaps are interchanged in order to lengthen scars or change their direction.
The principle of the “reconstructive ladder”
When choosing a procedure, plastic surgeons follow the principle of choosing the simplest adequate method: from direct suture through skin grafts and local flaps to the free microsurgical flap. Today this principle is applied more flexibly – sometimes the more complex procedure is the best functionally and aesthetically from the outset.
Note: This article is for general information only and does not replace medical advice.
Sources and further information
- Considerations in Flap Selection for Soft Tissue Coverage of the Hand and Digits (PMC)
- Simple to Extreme: Following the Reconstructive Ladder for Complex Posterior Trunk Reconstruction (PMC)
- Weichteildefekte nach Tumorresektion an Extremitäten und Rumpf: plastisch-rekonstruktive Konzepte (PubMed)
