In this Article
The rotation flap has 4 specific design features to its geometry: triangulation of an excised lesion, in which the apex of the triangle coincides with the geometrical pivot point, and is closed with a flap circumference 4-6 times the width of the defect. The back cut remains an effective modification when necessary.
Triangulating the lesion
The technique for triangulating the excised lesion is often overlook and current evidence for the “perfect design” is lacking. An isosceles triangle is preferred due to its symmetry and ease of use. An isosceles triangle fits more readily into a semicircular flap than a right-angled triangle1.
Clinical Pearl: By increasing the length of the triangle excision, the defect size reduces in size (width) and angle, the radius of the increases. Essentially, allows for an easier closure.
In relation to geometry, there is no exact flap circumference ratio. The literature has been inconsistent regarding the ideal flap circumference and defect width ratio. Classic textbooks with have guided plastic surgery teaching all vary slight (McGregor, Smith).
The circumference can be design in relation to the width or the length of the base of the defect:
- 5-8 times the width of the defect
- 4-5 times the length of the base of the defect
Variations do exist with flap circumference. Generally speaking, it is often not necessary to extend the arc of rotation to more than 90 degrees to the axis of the defect.
Clinical Pearl: As the flap circumference increases, the effectiveness of decreasing tension reduces.
The exact “pivot point” of a rotational flap can be defined in two ways:
- Functional pivot point: point of origin of the line of tension
- Geometrical pivot point: is the centre of the circle formed in part by the semicircular flap. This point should coincide with apex of triangulation.
Clinical Pearl: Moving the geometrical pivot point away from the apex of triangular defect results in an increase in closing tension.
Alterations to Reduce Tension
- Commonest technique to reduce tension.
- Moves the functional pivot point towards the defect.
- Decrease in closing tension is directly and inversely proportional to the length of the back cut1. This should be a balance, however, with cosmesis and compromise to blood supply.
- Less likely in sacral areas with laxity. For example, for pressure sores, pilonidal disease or hidradenitis suppurativa.
- A triangle of skin can be removed from the area adjacent to the pivot point of the flap to aid its advancement and rotation.
- This method is of only modest benefit in decreasing tension along the radius of the flap.
- Another option, commonly used, is to widely undermined along with the surrounding skin, making certain to release the area of greatest pivotal restraint that often lies at the end of the arc.
- This is necessary for the flap to gain the maximum range of movement and is best performed under visualization to avoid disrupting its vascular supply. This is described in more detail here
Double Rotation Flaps
- Consider in insufficient laxity to allow for closure with a single-sided flap3.
- 2 arcs originate from the same point of a circular defect but extending in the opposite directions (clockwise and one counterclockwise) to form a semicircular incision4
- Same principles of flap design.
- Commonly used to repair defects on forehead, lip, chin where the scar is hidden in hair, vermillion and mental creases
O-Z Rotation Flap
- 2 rotation are inverted relative to each another.
- Flap produces a scar that is roughly shaped like the letter Z
- This flap is particularly helpful in scalp defects.
- This isn't to be confused with Z-plasty
Periocular Rotation Flaps
- Mustarde and Tenzel each described techniques to repair defects of the lower eyelid.
- Tenzel Flap: a semicircular flap involves rotation of skin and orbicularis muscle from the area superior to the lateral canthus to fill defects of the lower lid and incorporates lysis of the lateral canthal tendon to increase tissue mobility5
- Mustarde Flap: described a similar design in which a broad sweeping rotation is arched superiorly from the lateral canthus, through the temple, and ending in the preauricular sulcus6
- 1. Lo CH, Kimble FW. The ideal rotation flap: an experimental study. Journal of Plastic, Reconstructive & Aesthetic Surgery. July 2008:754-759. doi:10.1016/j.bjps.2007.12.032
- 2. Ahuja R. Geometric considerations in the design of rotation flaps in the scalp and forehead region. Plast Reconstr Surg. 1988;81(6):900-906. doi:10.1097/00006534-198806000-00012
- 3. Albom M. Repair of large scalp defects by bilateral rotation flaps. J Dermatol Surg Oncol. 1978;4(12):906-907. doi:10.1111/j.1524-4725.1978.tb00578.x
- 4. Tenzel R, Stewart W. Eyelid reconstruction by the semicircle flap technique. Ophthalmology. 1978;85(11):1164-1169. doi:10.1016/s0161-6420(78)35578-0
- 5. Mustardé J. The use of flaps in the orbital region. Plast Reconstr Surg. 1970;45(2):146-150. https://www.ncbi.nlm.nih.gov/pubmed/5411895.