Variation in the insertion of the latissimus dorsi & its clinical importance

Abstract

The latissimus dorsi is the larger, flat, dorso-lateral muscle on the trunk, posterior to the arm, and partly covered by the trapezius on its median dorsal region. Origin of the latissimus dorsi is from spinous processes of thoracic T7-T12, thoracolumbar fascia, iliac crest and inferior 3 or 4 ribs, inferior angle of scapula and insertion on floor of intertubercular groove of the humerus. We have studied 50 cadavers in the different medical colleges in which we found 2% case of anterior and posterior slip of the muscle fibers with their extension up to the pectoralis major and teres major respectively. Usually, latissimus dorsi involve in extension, adduction, transverse extension also known as horizontal abduction, flexion from an extended position, and internal rotation of the shoulder joint. It also has a synergistic role in extension and lateral flexion of the lumbar spine. The latissimus dorsi may be used for the tendon graft surgeries. Tight latissimus dorsi has been shown to be one cause of chronic shoulder pain and chronic back pain. Because the latissimus dorsi connects the spine to the humerus, tightness in this muscle can manifest as either sub-optimal glenohumeral joint function (which leads to chronic shoulder pain) or tendinitis in the tendinous fasciae connecting the latissimus dorsi to the thoracic and lumbar spine. Latissimus dorsi used for pedicle transplant rotator cuff repair reconstruction of breast, face, scalp and cranium defect. The extra slip of the latissimus dorsi may puzzle any transplant operations. We as anatomist discuss the clinical implication of the extra slip of latissimus dorsi.

Back Muscles

“…In a cadaver with a typical axillary arch muscle, Bhatt et al (2013) described another slip of muscle that ran from the latissimus dorsi muscle across the posterior aspect of the axilla (behind the neurovascular bundle) to attach to the teres major muscle. In a cadaver with a typical axillary arch muscle, Bhatt et al (2013) described another slip of muscle that ran from the latissimus dorsi muscle across the posterior aspect of the axilla (behind the neurovascular bundle) to attach to the teres major muscle.…”

The musculoskeletal consequences of breast reconstruction using the latissimus dorsi muscle for women following mastectomy for breast cancer: A critical review

“…The LD muscle is a fundamental component involved in shoulder function, essential in internal rotation, extension and shoulder adduction (Bhatt et al, 2013;Forthomme et al, 2010;Giordano et al, 2011;Sowa et al, 2016). The LD muscle is a fundamental component involved in shoulder function, essential in internal rotation, extension and shoulder adduction (Bhatt et al, 2013;Forthomme et al, 2010;Giordano et al, 2011;Sowa et al, 2016).…”

“…As a result, there appears to be no consensus in the literature regarding the extent and impact of breast reconstruction using LD flap on musculoskeletal function. The LD muscle is a fundamental component involved in shoulder function, essential in internal rotation, extension and shoulder adduction (Bhatt et al, 2013;Forthomme et al, 2010;Giordano et al, 2011;Sowa et al, 2016). There have been many studies examining the application of the LD flap in various forms of reconstruction; however, relatively few studies have been conducted with regard to the functional impairment associated with LD muscle transfer in breast reconstruction.…”

“…Following mastectomy, the LD is dissected along with a skin paddle and overlying fat (de Oliveira, Pinto e Silva, Gurgel, Pastori-Filho, & Sarian, 2010;Kim et al, 2013;Smith, 2014). The LD is the largest muscle in the human body (Ciesla & Bak, 2012;Forthomme et al, 2010) and acts on the shoulder during adduction, medial rotation, extension and assists the scapula in depression (Bhatt et al, 2013;Forthomme et al, 2010;Giordano, Kaariainen, Alavaikko, Kaistila, & Kuokkanen, 2011;Sowa et al, 2016;Spear & Hess, 2005). The LD is a large flat muscle and is therefore often further augmented with implants or fat grafting to provide adequate symmetry and cosmesis (Fraser et al, 2013;Smith, 2014;Teymouri et al, 2006).…”

“…The LD is a large flat muscle and is therefore often further augmented with implants or fat grafting to provide adequate symmetry and cosmesis (Fraser et al, 2013;Smith, 2014;Teymouri et al, 2006). The LD is the largest muscle in the human body (Ciesla & Bak, 2012;Forthomme et al, 2010) and acts on the shoulder during adduction, medial rotation, extension and assists the scapula in depression (Bhatt et al, 2013;Forthomme et al, 2010;Giordano, Kaariainen, Alavaikko, Kaistila, & Kuokkanen, 2011;Sowa et al, 2016;Spear & Hess, 2005). The LD is thus involved in shoulder motion and plays an important role in shoulder joint biomechanics; the removal or replacement of this versatile muscle would be expected to affect shoulder movement, however, the extent to which this occurs is unknown.…”