A A M J Anveshana Ayurveda Medical Journal www.aamj.in ISSN: 2395-4159 Case Report Variation in Pattern of Rectus Sheath and Rectus Abdominis muscle w.s.r. to Diastasis Recti Teena Jain 1 Sunil Kumar Yadav 2 A b s t r a c t In modern anatomy muscles are studied as a separate branch Myology. The name muscle was given on the basis of the shape i.e. Mouse-like. Acharya Sushruta said that 500 Peśi in the human male body and 520 in the female body. Out of 500 nearly 400 are present in the Śākha, 66 in the Koshtha and 34 in the Śiras. Rectus abdominis is the muscle of anterior abdominal wall and covered into the rectus sheath. Rectus sheath formed from the aponeurosis of antero-lateral group of abdominal muscles and this sheath fused in mid line and forms linea alba. Medial border of these two muscles close to median plane. But in this case some variation found during dissection. Key Words: Peśi, rectus abdominis muscle, rectus sheath, linea alba. 1 Ph.D Scholar, 2 Assistant Professor, Dept.of Sharir Rachana, National Institute of Ayurveda, Jaipur, Rajasthan. CORRESPONDING AUTHOR Dr. TEENA JAIN Ph.D. Scholar, Dept.of Sharir Rachana, National Institute of Ayurveda, Jaipur, Rajasthan Email: jainteena1186@gmail.com AAMJ / Vol. 2 / Issue 4 / July August 2016
INTRODUCTION Myology is the study of muscles. More than 600 skeletal muscles make up the muscular system, and technically each one is an organ it is composed of skeletal muscle tissue, connective tissue, and nervous tissue. Each muscle also has a particular function, such as moving a finger or blinking an eyelid. Collectively, the skeletal muscles account for approximately 40% of the body weight. According to Acharya Charaka Śarir (body) consists of the following parts; the two arms, the two legs, the head and neck, and the trunk. These make up the hexa partite body [i]. Same, according to Acharya Sushruta the human body is composed of six main parts, namely the four extremities, the middle body and the head. [ii] Śākha- denotes to extremities. Madhya Śarir or Antarādhi is the trunk which inturn includes thorax and abdomen. Śir and Grīva is head and neck. Head also includes face in it. According to Acharya Sushruta there are 500 Peśi in the human male body and 520 in the female body. Out of 500 nearly 400 present in the Śākha, 66 in the Kośtha and 34 in the Śiras. [iii] Muscle of abdomen & thorax are nicely described by Sushruta. Sushruta has described that 5 Peśi are present in the Udara(abdominal) region. [iv] Anterior Abdominal Wall [v] The abdomen is roughly cylindrical chambers extending from inferior margin of thorax to superior margin of pelvis & the lower limb. The wall consists partly of bone but mainly of muscles. The skeletal element of wall is formed by various muscles. There are five muscles in anterior abdominal wall or anteriolateral group. Three flat muscles whose fibers begin postero-laterally pass anteriorly & are replaced by aponeurosis as the muscles continuous towards the midline by external oblique, internal oblique & transverse abdominis muscles. Two vertical muscles i.e. rectus abdominis muscle and pyramidalis near the midlines which are enclosed within a tendinous sheath formed by aponeurosis of flat muscles. Rectus abdominis muscle Rectus abdominis is a long, strap-like muscle that extends along the entire length of the anterior abdominal wall. It is widest in the upper abdomen and lies just to the side of the midline. The paired recti are separated in the midline by the linea alba. The muscle fibres of rectus abdominis are interrupted by three fibrous bands or tendinous intersections. One is usually situated at the level of the umbilicus, another opposite the free end of the xiphoid process and a third about midway between the other two. They usually fuse with the fibres of the anterior lamina of the sheath of the muscle. The medial border of rectus abdominis is closely related to the linea alba. Its lateral border may be visible on the surface of the anterior abdominal wall as a curved groove, the linea semilunaris, which extends from the tip of the ninth costal cartilage to the pubic tubercle. Attachments Rectus abdominis arises by two tendons. The larger, lateral tendon is attached to the crest of the pubis and may extend beyond the pubic tubercle to the pectineal line. The medial tendon interlaces with the contralateral muscle and blends with the ligamentous fibres covering the front of the symphysis pubis. Additional fibres may arise from the lower part of the linea alba. Superiorly, rectus abdominis is attached by three slips of muscle to the fifth, sixth and seventh costal cartilages. The most lateral fibres are usually attached to the anterior end of the fifth rib. The most medial fibres are occasionally connected to the costoxiphoid ligaments and the side of the xiphoid process. Vascular supply- Innervation- Mainly by the superior and inferior epigastric arteries. Partially from small terminal branches from the lower three posterior intercostal arteries, the subcostal artery, the posterior lumbar arteries and the deep circumflex artery. Rectus abdominis is innervated by the terminal branches of the ventral rami of the lower six or seven thoracic spinal nerves via the lower intercostal and subcostal nerves. Actions- The recti contribute to the flexion of the trunk. They also contribute to the maintenance of abdominal wall tone required during straining. AAMJ / Vol. 2 / Issue 4 / July August 2016 810
Rectus sheath Rectus abdominis on each side is enclosed by a fibrous sheath. The rectus sheath is formed from decussating fibres from all three lateral abdominal muscles. External oblique, internal oblique and transversus abdominis each forms a bilaminar aponeurosis at their medial borders. Rectus sheath is divided into anterior and posterior laminae. The arrangement of the layers has important variations at different locations in the body. Above costal margin - The anterior rectus sheath is formed from aponeurosis of external oblique muscle. In posterior side the sheath is deficient, so muscle is directly attached to the ribs. Between costal margin and arcuate line - The anterior rectus sheath is composed of both leaves of the aponeurosis of external oblique and the anterior leaf of the aponeurosis of internal oblique fused together. The posterior rectus sheath is composed of the posterior leaf of the aponeurosis of internal oblique and both leaves of the aponeurosis transversus abdominis. Below arcuate line - The anterior rectus sheath is composed of all three muscles. The posterior rectus sheath is composed of only fascia transversalis. Linea alba The linea alba is a tendinous raphe extending from the xiphoid process to the symphysis pubis and pubic crest. It lies between the two recti and is formed by the interlacing and decussating aponeurotic fibres of external oblique, internal oblique and transversus abdominis. It is visible only in the lean and muscular, as a slight groove in the anterior abdominal wall. A fibrous cicatrix, the umbilicus, lies a little below the midpoint of the linea alba, and is covered by an adherent area of skin. Below the umbilicus, the linea alba narrows progressively as the rectus muscles lie closer together. Above the umbilicus, the rectus muscles diverge from one other and the linea alba is correspondingly broader. The linea alba has two attachments at its lower end: its superficial fibres are attached to the symphysis pubis, and its deeper fibres form a triangular lamella that is attached behind rectus abdominis to the posterior surface of the pubic crest on each side. This posterior attachment of linea alba is named the adminiculum lineae albae'. The linea alba is crossed from side to side by a few minute vessels. Fig. No. 1 Normal Rectus Sheath and Rectus Abdominis Muscle. CASE REPORT During routine gross anatomy dissection of anterior abdominal wall in National Institute of Ayurveda, Jaipur we observe a rare case of variation of left side of rectus abdominis muscle and rectus sheath. Generally right and left side of rectus abdominis muscle covers in rectus sheath and this sheath fused in mid line and forms linea alba. Medial border of these two muscles close to median plane. But in this case the medial border of left side rectus abdominis muscle is away from median plane and the space between two recti is formed. In this space some defect is present i.e. hernia. Materials and Methodology- Materials- For literary study: 1. Available literature regarding rectus abdominis muscle and rectus sheath from Modern texts. 2. Research Journals or papers presented on the related topics. 3. Authentic Internet sources. For cadaveric dissection Study: 1. Cadaver: Female 2. Dissection kit Methodology- Literature Study: All the information regarding rectus abdominis muscle and rectus sheath was collected from modern texts, research journals or pa- AAMJ / Vol. 2 / Issue 4 / July August 2016 811
pers presented on the related topics and authentic internet sources. Cadaveric Study: - Cadaveric dissection was done in the dissection hall of department of Śarira Rachana of NIA, Jaipur. While studying the dissected cadaver, photo images were taken with the help of digital camera. Dissection of the anterior abdominal wall was done on cadaver by using dissection kit; Cunningham s manual of practical anatomy, Grant s Dissector and Frank H. Netter for understanding the variation of rectus abdominis muscle and rectus sheath. DISCUSSION Rectus abdominis muscle is the vertical muscle of anterior abdominal wall. These are paired muscle and covered in rectus sheath. Rectus sheath is formed from aponeurosis of external oblique, internal oblique and transversus abdominis muscle. The right and left side of rectus sheath fused in midline and formed linea alba. When we dissected female cadaver we found that the medial border of left side rectus abdominis muscle is away from median plane and the space between two recti is formed. This case represents the diastasis recti also known as abdominal separation. Diastasis recti - This is commonly defined as a gap of roughly 2.7 cm or greater between the two sides of the rectus abdominis muscle. This condition has no associated morbidity and mortality. The distance between the right and left rectus abdominis muscle is created by the stretching of the linea alba. Diastasis of this muscle occurs principally in two populations; newborns and pregnant women. Women are more susceptible to develop diastasis recti when over the age of 35, high birth weight of child, multiple birth pregnancy, and multiple pregnancies. Additional causes can be attributed to excessive abdominal exercise after the first trimester of pregnancy. Diastasis recti may appear as a ridge running down the midline of the abdomen, anywhere from the xiphoid process to the umbilicus. During dissection we found that some structures bulge out below the umbilicus and the gap between two recti. This structure may be abdominal viscera or the only peritoneum. This bulging is not true herniation, because all the layers of the abdominal wall in that region are intact. CONCLUSION Rectus abdominis is the muscle of anterior abdominal wall and covered in rectus sheath. In this case, a gap present between two recti muscles and linea alba is not clearly defined. Some structures may be abdominal viscera or membrane bulge out in this gap below the umbilicus. In this site where the bulging present, all the layers of the abdominal wall are intact, so it is not true hernia. ΛΛΛΛ Fig. 2 Abnormal Rectus Sheath and Rectus Abdominis Muscle AAMJ / Vol. 2 / Issue 4 / July August 2016 812
REFERENCES i. Charaka Samhita (Agnivesh) Part 1- elaborated vidyotini Hindi Commentary by pt. kasinatha sastri and dr. gorakha natha chaturvedi, Published by Chaukhambha Bharati Academy, Gokul Bhawan, Gopal Mandi Lane,Varanasi, 2005, Page No. 911. ii. Dalhana, Nibandhasangraha Commentary of Sushruta, 2012, Page No. 363. iii. Dalhana, Nibandhasangraha Commentary of Sushruta, 2012, Page No. 367. iv. Dalhana, Nibandhasangraha Commentary of Sushruta, 2012, Page No. 368. v. Grey s anatomy for students- byrichard L Drake, Wayne Vogl, Adam W.M. Mitchell Elsevier Churchil Philadelphia Edinburgh London 2005 international edition ISBN- 0808923064 page no.-246-250. Source of Support: Nil. Conflict of Interest: None declared How to cite this article: Teena & Sunil : Variation in Pattern of Rectus Sheath and Rectus Abdominis muscle w.s.r. to Diastasis Recti. AAMJ 2016; 4:809 813 ΛΛΛΛ AAMJ / Vol. 2 / Issue 4 / July August 2016 813