Introduction: 

• The latissimus flap is one of the largest muscles in the body and one of our workhorse flaps in plastic surgery
• Based off of the subscapular system and can be raised as a muscle/myocutaneous flap, multi component including skin, muscle, bone off of the scapula system
• Can be used as a pedicled flap in breast and chest wall reconstruction, or as a free flap all over the body (lower extremity, scalp, etc)

• Posterior Trunk Anatomy as it relates to the latissimus…
• Latissimus originates from the 7-12th thoracic vertebrae, lumbar, and sacral spinous processes as well as the middle/outer rim of the iliac crest
• Inserts on the medial lip of the intertubercular groove of the humerus
• Superior border of the muscle is covered by the trapezius, but is superficial to all other muscles of the back

• Vascular Anatomy:
• Type 5 muscle flap – dominant pedicle and secondary minor pedicles that the flap CAN survive on
• Dominant – Thoracodorsal 
• Subscapular artery arises from third portion of axillary artery, gives off the circumflex scapular, angular branch, serratus branch and then continues as the thoracodorsal
• TD divides into a lateral branch – parallels anterior border of muscle and medial branch which parallels upper border of muscle
• Secondary – Intercostal perforators
• Can be used as a “turnover flap” to cover posterior trunk wounds 
• Venous drainage is through the thoracodorsal VEIN
• Innervation – TD nerve which also has a medial/lateral branch which parallel the artery

• Technical Pearls:
• Pedicle typically enters the flap 10-12cm below posterior axillary fold
• Flap can be harvested in the lateral position with the arm abducted, OR in the supine position
• Many modifications to the latissimus including a “split latissimus” “turnover latissimus” “Extended latissimus” and a TDAP flap (will discuss later)
• Postoperative Care
• Donor site morbidity is often discussed, the typical answer is that despite the size of the muscle there is MINIMAL donor site morbidity in terms of functional deficits
• Some studies do cite up to 7% decrease in shoulder function (variable) but have seen videos of someone doing pullups after a latissimus
• Most common Complications:
• Seroma formation
• Compression therapy
• Progressive tension sutures
• Fibrin glue, Triamcinolone
• DRAINS