(A) External iliac
(B) Femoral
(C) Internal iliac
(D) Internal mammary
(E) Superficial inferior epigastric

The correct response is Option A.

The deep inferior epigastric artery and vein arise from the external iliac artery at a point just proximal to where the artery passes beneath the inguinal ligament.

The internal mammary vessels provide the regional source for the superior epigastric artery. The femoral, internal iliac, and superficial inferior epigastric arteries are not source vessels for the deep inferior epigastric artery and vein. The femoral artery originates as the external iliac vessels exit from the inguinal ligament. The internal iliac artery supplies blood to structures within the pelvis.

Reference
1. Mathes SJ, Nahai F, eds. Reconstructive Surgery: Principles, Anatomy, and Technique. Saint Louis, Mo: Quality Medical Publishing, Inc; 1997:1043.

The third perforating branch of the profunda femoris artery, which is the blood supply for the lateral thigh flap, originates at a level that is immediately caudad to which of the following muscles?

(A) Adductor brevis
(B) Adductor longus
(C) Adductor magnus
(D) Gracilis
(E) Pectineus

PHOTO

The correct response is Option A.

The third perforating branch of the profunda femoris artery provides the predominant blood supply for the lateral thigh flap. The third perforating branch originates immediately caudad to the adductor brevis muscle, pierces the insertion of the adductor magnus, courses superficially, and then traverses between the biceps femoris and the vastus lateralis. It pierces the deep fascia at this point, and then emerges at the midpoint between the greater trochanter and lateral epicondyle of the femur.

The lateral thigh flap is a versatile flap that has a thin, cutaneous skin paddle and is innervated by the lateral cutaneous nerve of the thigh. As much as 8 * 25 cm can be transferred; however, split-thickness skin grafting is required for closure at the donor site if a flap with a width of greater than 8 cm is harvested. In addition, the lateral aspect of the thigh flap can be hair-bearing, especially in men, while the dermis is characteristically thick and stiff.

The adductor longus muscle originates at the pubic ramus and inserts on the medial epicondyle. The gracilis muscle in the thigh is perfused by the medial circumflex artery, while the pectineus muscle receives its vascularity from the first perforating branch of the profunda femoris.

References
1. Baek SM. Two new cutaneous flaps: the medial and lateral thigh flaps. Plast Reconstr Surg. 1983;71:354.
2. Strauch B, Yu HL. Atlas of Microvascular Surgery. New York, NY: Thieme Medical Publishers, Inc; 1992:190-193.
3. Urken ML, Sullivan MJ. Lateral thigh. In: Urken ML, Cheney ML, Sullivan MJ, eds. Atlas of Regional and Free Flaps for Head and Neck Reconstruction. New York, NY: Raven Press; 1995:169-182.

According to the Mathes-Nahai classification of muscle and musculocutaneous flaps, which of the following is a type I flap?

(A) Gluteus maximus
(B) Gracilis
(C) Latissimus dorsi
(D) Sartorius
(E) Tensor fascia lata

The correct response is Option E.

The tensor fascia lata, gastrocnemius, and vastus lateralis muscle flaps have a type I vascular pattern consisting of one dominant pedicle. These muscles can be used as rotation flaps for regional reconstruction or as free tissue for transfer.

Type II muscle flaps have one dominant pedicle and several minor pedicles; examples include the abductor digiti minimi, gracilis, and soleus. In type III muscle flaps, such as the gluteus maximus, rectus abdominis, and serratus, there are two dominant vascular pedicles. The extensor hallucis longus, sartorius, and tibialis anterior muscle flaps have a type IV vascular pattern, with multiple segmental vascular pedicles entering along the course of the muscle belly. Type V muscle flaps, such as the latissimus dorsi and pectoralis major, have one dominant pedicle and secondary segmental pedicles, which provide a significant source of muscle circulation.

Reference
1. Mathes SJ, Nahai F. Classification of the vascular anatomy of muscles: experimental and clinical correlation. Plast Reconstr Surg. 1981;67:177.
2. Mathes SJ, Nahai F, eds. Reconstructive Surgery: Principles, Anatomy, and Technique. Saint Louis, Mo: Quality Medical Publishing, Inc; 1997:1043.

Which of the following muscles comprise the boundaries of the triangular space in which the circumflex scapular artery is located?

(A) Infraspinatus, latissimus, and teres minor
(B) Latissimus, long head of the triceps, and teres major
(C) Latissimus, teres minor, and teres major
(D) Long head of the triceps, supraspinatus, and teres major
(E) Long head of the triceps, teres major, and teres minor

The correct response is Option E.

The boundaries of the triangular (or omotricipetal) space, in which the circumflex scapular artery is located, are comprised of the long head of the triceps muscle laterally, the teres major muscle inferiorly, and the teres minor muscle superiorly. The circumflex scapular artery is a branch of the subscapular artery and emerges from the triangular space to supply blood to the parascapular flap.

The quadrangular space can be found immediately lateral to the triangular space. This space is defined by the surgical neck of the humerus, lateral head of the triceps muscle, teres major muscle, and teres minor muscle. The axillary nerve and posterior humeral circumflex artery pass through this space.

The other muscles listed above can be identified in the region of the shoulder and trunk but do not define the triangular space.

Reference
1. Jones NF, Lister GD. Free skin and composite flaps. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;2:1159-1200.