The Conjoined Sternalis-Pectoralis Muscle Flap in Immediate Tissue Expander Reconstruction After Mastectomy

An unusual finding of the pectoralis major muscle: decussation of sternal fibers across the midline

Variations of the pectoralis major muscle are commonly seen. However, during the routine dissection of an adult male cadaver, an apparently uncommon muscular variant was identified. In this cadaver, the sternal heads of the left and right pectoralis muscles crossed the midline and interdigitated with one another. In addition, the clavicular heads of both pectoralis major muscles were separated from the remaining parts of the muscles. Such anatomical variants such be kept in mind by clinicians and surgeons during patient evaluation and treatment.

Sternalis muscle, what every anatomist and clinician should know

The sternalis muscle is a well documented but rare muscular variation of the anterior thoracic wall. It lies between the superficial fascia and the pectoral fascia and is found in about 8% of the population. It presents in several morphological variants both unilaterally and bilaterally and has no apparent physiological function. There is still much disagreement about its nerve supply and embryological origin. With the advent of medical imaging and thoracic surgery the clinical importance of this muscle has been re-emphasized. It has been implicated in misdiagnosis of breast masses on routine mammograms owing to its parasternal location and relative unfamiliarity among radiologists. When undetected before any thoracic surgery, it has the potential to interfere with and prolong such procedures. When present and detected preoperatively it can be used as a muscular flap in reconstructive surgeries of the breast and neck. This article will present the sternalis muscle with special emphasis on its morphology, homology, and clinical significance.

Biceps sternalis: a Y-shaped muscle on the anterior chest wall

The sternalis muscle is an accessory muscle located in the anterior thoracic region, which is relatively unfamiliar to clinicians and surgeons. To date, no data from the Iranian population have been published. Here, a rare case of a sternalis muscle is presented. In addition, this anomalous muscle was observed along with other visceral and vascular anomalies. This case is unique and provides significant information to radiologists, angiologists and surgeons seeking to apply safer interventions. It is also imperative for better interpretation of mammographic images and in reconstructive surgery.

Incidental finding of the sternalis muscle on chest multidetector-row computed tomography (MDCT): the diagnostic value of additional postprocessed MDCT images for an uncommon muscular variant

We herein report two cases of incidental finding of the sternalis muscle in the right anterior chest wall on multidetector-row computed tomography (MDCT). We emphasize the diagnostic utility and value of additional postprocessed MDCT images, which can be easily created using volume data sets of MDCT, in establishing an accurate diagnosis of the sternalis muscle, an uncommon muscular variant.

The sternalis muscle: radiologic findings on MDCT

PURPOSE

The purpose of this study was to characterize and determine the prevalence of the sternalis muscle using 64-row multidetector computed tomography (MDCT).

MATERIALS AND METHODS

We retrospectively reviewed MDCT chest scans that were performed in a hospital during the course of a month. The study population consisted of 948 consecutive patients (511 males and 467 females). On the MDCT scans the sternalis muscle was defined as the longitudinal muscle lying on and superficial to the pectoralis major muscle.

RESULTS

The prevalence of the sternalis muscle was 10.5 %. The muscle was present more frequently in females (13.0 %) compared to males (8.4 %) (P = 0.02). In the majority of patients, the muscle was located longitudinally in the parasternal position; however, in two patients it was positioned across the sternum. One hundred twenty were flat types, while the remaining five had oblique shapes. The muscle mean height, width and depth were 77.9 ± 25.1, 19.4 ± 12.2 and 2.8 ± 1.3 mm, respectively. The muscle was wider in males compared to females (P < 0.001).

CONCLUSION

Using MDCT, its prevalence was shown to be 10.5 %. This variant muscle can be differentiated from other pathological structures using its specific characteristic appearance.

Sternalis muscle revisted in South Indian male cadaver: a case report

Introduction

Sternalis/rectus sternalis is a rare muscle found in the chest wall. Only 3-5% of the cases are found world wide.

Case presentation

Here we report the case of Sternalis in the 60-year-old South Indian male cadaver. This report discusses the origin, orientation, relations of this muscle.

Conclusion

Importance of the knowledge of the presence of these rare muscles in clinical diagnosis and therapeutic implications is discussed.