Anatomical variations of the subscapular pedicle and its terminal branches: an anatomical study and a reappraisal in the light of current surgical approaches

Routine Contrasted Chest CT Accurately Identifies Anatomic Variations of the Proximal Subscapular System

OBJECTIVE

The vascular anatomy of the proximal subscapular artery has been previously classified into 2 major types depending on the presence of a common subscapular trunk. The purpose of this study was to determine the utility, reliability, and cost of routine chest imaging to identify these anatomical variations.

METHODS

Data were collected retrospectively at a tertiary medical center for patients who were undergoing CT chest for various indications between October 2019 and October 2020. Two independent and blinded readers interpreted CT chest with contrast of 52 patients for a total 104 sides.

RESULTS

The proximal branching pattern of the subscapular system was identified to have a common trunk in 99 (95%) sides. The remaining five sides (5%) demonstrated two arterial pedicles; with one patient exhibiting the variant anatomy bilaterally.

CONCLUSION

Preoperative CT chest with contrast can accurately identify anatomic variation of the subscapular vascular system. For complex reconstruction requiring a single anastomosis in the vessel depleted neck, preoperative imaging can assure selection of a type I vascular anatomy of the proximal subscapular system. Preoperative imaging with contrasted CT has value in assessing this anatomy when planning for chimeric flaps involving circumflex scapular and thoracodorsal arteries.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:684-687, 2024.

Journal of Plastic, Reconstructive and Aesthetic Surgery Venous system mapping of the digits and the hand: an anatomical study and potential surgical applications

Background

Venous anatomy of the digits and the hand is poorly reported in the literature compared to arterial anatomy. While knowledge of the venous anatomy is crucial to ensure safe skin incisions, skin flap design, or blood return restoration for digital replantations, data in anatomical and clinical textbooks are rather limited. The purpose of this anatomical study was to describe the venous anatomy of the digits and the hand.

Method

Our series reports descriptive results from 10 non-embalmed hand dissections from 5 different corpses. Hands were previously co-injected by arteries followed by veins with a different colored latex before being dissected under optical magnification (x4). Each anatomical specimen was photographed before being analyzed.

Results

Each injection revealed both arterial and venous vascular systems. Latex injections were a useful technique to show the dorsal, volar superficial, and deep venous system. There was a constant and reliable topographic vascular anatomy of the superficial venous system of the digits and hand. However, we could not observe a high density of dorsal superficial venous valves as previously reported.

Conclusion

The knowledge of the arrangement of the venous system of the digits and the hand should help the surgeon when performing surgical procedures in the hand. The surgeon should take into consideration this venous anatomy when performing skin incisions, skin flaps, or replantation procedures which would preserve the normal venous physiology as much as possible.

Anatomic variants of the subscapular-thoracodorsal arterial system: A radiologic analysis of 200 arterial systems

BACKGROUND

Composite flaps based on the subscapular arterial system are excellent choices for complex defects, including those of the head and neck, though rates of anatomic variants are not well described.

OBJECTIVE

Characterize subscapular-thoracodorsal arterial system in a large cohort of patients using CT chest angiography.

METHODS

CTA chest studies from 100 adult patients were analyzed to characterize the bilateral subscapular-thoracodorsal arterial systems.

RESULTS

Out of 200 arterial systems, 25 (12.5%) were lacking a subscapular artery, with the thoracodoral and circumflex scapular arteries arising independently off of the axillary (or other nearby vessels). Strikingly, the subscapular artery was absent bilaterally in 5 patients and absent unilaterally in 15 patients, meaning that one in five patients harbored abnormal anatomy on at least one side. There was no radiographic evidence of atherosclerosis in the studied vessels in any patient, including smokers and patients with atherosclerosis in other vessels.

CONCLUSION

Variations in the subscapular-thoracodorsal arterial system appear more frequent than previously described. For select patients requiring complex reconstruction using the scapular system, CTA chest may aide surgical planning.

Upper limb arterial pattern: clinical correlation and embryological perspective

Background

Variations in the upper limb arterial pattern are commonplace and necessitate complete familiarity for successful surgical and interventional procedures. Variance in the vascular tree may involve any part of the axis artery of the upper limb, including the axillary artery and brachial artery or its branches, in the form of radial and ulnar arteries, which eventually supply the hand via anastomosing arches.

Objectives

To study the peculiarities of the arterial pattern of the upper limb and to correlate them with embryological development.

Methods

The entire arterial branching of forty-two upper limbs of formalin fixed adult human cadavers was examined during routine dissection for educational purposes, conducted over a 3-year period in the Department of Anatomy, Lady Hardinge Medical College, New Delhi.

Results

The study found: 1) One case in which a common trunk arose from the third part of the axillary artery, which immediately splayed into four branches (2.4%); 2) High division of the brachial artery into ulnar and radial arteries, in 3 cases (7.1%); 3) Pentafurcation of the brachial artery into ulnar, interosseus, radial, and radial recurrent arteries and a muscular twig to the brachioradialis in 1/42 cases (2.4%); 4) Incomplete Superficial Palmar arch in 3/42 cases (7.1%); and 5) Presence of a median artery in 2/42 case(4.8%)

Conclusions

This study observed and described the varied arterial patterns of the upper limb and identified the various anomalous patterns, supplementing the surgeon’s armamentarium in various surgical procedures, thereby helping to prevent complications or failures of reconstructive surgeries, bypass angiography, and many similar procedures.

Immediate Lymphatic Reconstruction: Technical Points and Literature Review

Recent studies have provided evidence that lymphovenous bypass—microsurgical re-routing of divided lymphatics to an adjacent vein—performed at the time of lymph node dissection decreases the rate of lymphedema development. Immediate lymphatic reconstruction in this setting is technically demanding, and there is a paucity of literature describing the details of the surgical procedure. In this report, we review the literature supporting immediate lymphatic reconstruction and provide technical details to demystify the operation for surgeons who wish to provide this option to their patients.

Descriptive anatomy of the inferior epigastric, subscapular and internal thoracic vascular pedicles in three domestic mammals: A comparative study

The descriptive anatomy of the inferior epigastric, subscapular and internal thoracic vascular pedicles of domestic animals is not fully known. Improvement of our knowledge in this field could lead to better development of animal models for both pedagogical purposes and surgical experimentation. The objective of this comparative study was to describe the descriptive anatomy of the inferior epigastric, subscapular and internal thoracic pedicles in three domestic mammals commonly used as animal models for experimentation. Our study focuses on the anatomical description of these vascular pedicles in the rat (Rattus norvegicus) (n=1), the rabbit (Oryctolagus cuniculus) (n=1) and the pig (Sus scrofa domesticus) (n=1). A comparative and analytical study of these vessels (origin, path, caliber, termination) with those of humans was carried out. The superficial inferior epigastric vascular pedicles have been identified only in rats and pigs. The deep inferior epigastric, subscapular and internal thoracic pedicles were identified in the three mammals studied. No perforator vessels for the subcutaneous tissue and skin were identify from the deep inferior epigastric pedicles. The anatomical characteristics (origin, path, termination) of these vascular pedicles in rabbits seems to be the closest to that of humans. However the caliber of these vessels is around a millimeter compared to a 2.0-3.0mm in humans. This comparative study allowed us to identify and better characterize the morphological characteristics of these vascular pedicles in three domestic mammals, a step prior improving the development of animal models intended for pedagogical or experimental purposes in the field of microsurgical free flaps.

Anatomy of the axillary arch: from its incidence in human to an embryologic and a phylogenetic explanation of its origins

INTRODUCTION

Typically, the axillary arch is defined as a fleshy slip running from latissimus dorsi to the anterior aspect of the humerus. Phylogeny seems to give the most relevant and plausible explanation of this anatomical variant as a remnant of the panniculus carnosus. However, authors are not unanimous about its origin. We report herein the incidence of axillary arch in a series of 40 human female dissections and present an embryologic and a comparative study in three domestic mammals.

MATERIALS AND METHODS

Forty formalin-preserved Caucasian human female cadavers, one rat (Rattus norvegicus), one rabbit (Oryctolagus cuniculus) and one pig (Sus scrofa domesticus) cadavers were dissected bilaterally. A comparative, analytical and a descriptive studies of serial human embryological sections were carried out.

RESULTS

We found an incidence of axillary arch of 2.5% (n = 1 subject of 40) in Humans. We found a panniculus carnosus inserted on the anterior aspect of the humerus only in the rat and the rabbit but not in the pig. The development of the latissimus dorsi takes place between Carnegie stage 16-23, but the embryological study failed to explain the genesis of the axillary arch variation. However, comparative anatomy argues in favour of a panniculus carnosus origin of the axillary arch.

CONCLUSIONS

With an incidence of 2.5% of cases, the axillary arch is a relatively frequent variant that should be known by clinician and especially surgeons. Moreover, while embryology seems to fail to explain the genesis of this variation, comparative study gives additional arguments which suggest a possible origin from the panniculus carnosus.