Groin Flap

10.1055/b-0034-78131

Groin Flap

Ghazi Rayan and Douglas Trzcinski

Groin flap is a viable option for patients who are not candidates for free tissue transfer because of comorbidities and when the utility of microvascular technique is not feasible. The groin flap is an axial-pattern distant flap that is elevated on its pedicle and inset to the primary defect.1 The surrounding tissues of the primary defect allow vascularization into the periphery and deep surface of the flap, thus providing a blood supply sufficiently robust for the vascular pedicle to be divided at a later stage. Although this vascularization process takes ~ 7–10 days, many surgeons allow 2 or rarely 3 weeks before dividing the pedicle to ensure achieving adequate blood supply through the bed and periphery. Once the flap pedicle is divided, the flap inset can be completed and the extremity mobilized.

Indications

The ideal candidate is a patient with a soft-tissue defect that is too large for local or regional flaps and who is not a candidate for free tissue transfer. Factors that preclude free tissue transfer include a large zone of injury and poor target vessels. The primary defect must be at a location, usually the dorsum of the hand or wrist, that allows positioning of the upper extremity for tension-free coverage during the delay period. Groin flap is also indicated for reconstruction of degloving injuries of the thumb, with or without bone graft.
Age range: A groin flap is useful for any age group from the child to the elderly; however, the older patient population may have residual digital joint stiffness because of underlying osteoarthritis and the immobilization period required for vascularization.
Timing: This flap is useful for defects that have been cleared of infection and necrotic tissues. Serial débridement procedures should be performed if necessary to achieve a tidy primary defect appropriate for coverage.

Contraindications

Absolute

Previous surgery, such as inguinal hernia repair or groin access procedures, that may have compromised the vascular pedicle
Peripheral vascular disease
Poor skin quality or infection in the groin area

Relative

Very large primary defects that render the flap insufficient for coverage
Patients with a history of systemic vasculitis that may compromise vascularization
Patients who may not tolerate hand immobilization in the groin during the delay period

Examination/Imaging

Clinical examination of the groin region to determine the presence and orientation of scars from previous interventions
Extremity defect to assess compatibility with proper orientation of the arm for flap inset during the delay period
Optional Doppler examination to locate the vascular pedicle precisely

Relevant Anatomy

The arterial supply of the groin flap is based on the superficial circumflex iliac (SCI) artery. The artery originates from either the femoral artery directly or from an origin common with the superficial inferior epigastric artery. The artery pierces the fascia at the lateral aspect of the femoral triangle and lies just superficial to the sartorius fascia as it passes the sartorius muscle. It then becomes more superficial as it courses laterally until it is most superficial near the anterior iliac spine. At this level, it arborizes into several branches.2,3

The major venous drainage of the flap is composed of a superficial system with numerous veins that drain into the SCI vein. The SCI vein courses parallel to the SCI artery and typically drains into the saphenous venous trunk or occasionally into the superficial inferior epigastric (SIE) vein. Occasionally, the SCI vein and SIE vein form a common vein. The flap also has a deep venous system consisting of one or two venae comitantes that accompany the SCI artery and typically drain into the femoral vein or the external iliac vein.4

Surgical Technique

Instrumentation

No special equipment is necessary for the coverage of upper extremity defects with the groin flap.
A tourniquet is helpful during preliminary preparation of the primary defect but not necessary for flap elevation or inset.
A Doppler unit may be used if desired for confirmation of the SCI artery course within the flap.
Standard instruments desired for soft-tissue procedures will typically suffice.