Axillary arch muscle and pectoralis quartus: an unusual combination of two variant supernumerary muscles in the axillary region - a case report.

Variant anatomy in the axillary region is of great clinical significance. It is one of the most frequently accessed regions for radical dissection surgery. During routine dissection of embalmed cadavers, we found a rare case of two accessory muscular slips emerging from the lateral border of latissimus dorsi (LD) and the inferolateral border of pectoralis major (PM), crossing the neurovascular structures in the axilla and merging distally together to the brachial fascia at the upper end of humerus below the bicipital groove. The accessory slip from LD is commonly referred to as the "axillary arch" in literature. We identified the accessory slip from the PM crossing over the axilla as pectoralis quartus. These aberrant slips can cause neurovascular compression in the axilla and can have clinical implications. Prior knowledge of the variant anatomy is the key to successful surgery in the axilla, thereby avoiding inadvertent injuries and post-operative complications.

The proximal humeral locking plate positioning to the pectoralis major tendon in achieving the proper calcar screw location: a cadaveric study.

BACKGROUND: Proximal humeral fracture is the third most common of osteoporotic fracture. Most surgical cases were treated by fixation with anatomical locking plate system. The calcar screw plays a role in medial support and improving varus stability. Proximal humerus fracture in elderly patients are commonly seen with greater tuberosity (GT) fracture. The GT fragment is sometimes difficult to use as an anatomic landmark for proper plate and screw position. Therefore, the insertion of pectoralis major tendon (PMT) may be used as an alternative landmark for appropriate plate and calcar screw position. The purpose of study is going to identify the vertical distance from PMT to a definite point on the position of locking plate. METHODS: 30 cadaveric shoulders at the department of clinical anatomy were performed. Shoulders with osteoarthritic change (n = 5) were excluded. Finally, 25 soft cadaveric shoulders were recruited in this study. The PHILOS™ plate was placed 2 mm posterior to the bicipital groove. A humeral head (HH) was cut in the coronal plane at the level of the anterior border of the PHILOS plate with a saw. A calcar screw was inserted close to the inferior cortex of HH. Distance from the upper border of elongated combi-hole (UB-ECH) to the upper border of pectoralis major tendon (UB-PMT) was measured. The plate was then moved superiorly until the calcar screw was 12 mm superior to the inferior border of HH and the distance was repeatedly measured. RESULTS: The range of distance from UB-PMT to the UB-ECH was from - 4.50 ± 7.95 mm to 6.62 ± 7.53 mm, when calcar screw was close to inferior border of HH and when the calcar screw was 12 mm superior to the inferior border of HH, respectively. The highest probability of calcar screw in proper location was 72% when UB-ECH was 3 mm above UB-PMT. DISCUSSION AND CONCLUSION: The GT fragment is sometimes difficult to use as an anatomic landmark for proper plate and screw position. PMT can be used as an alternative anatomic reference. UB-PMT can serve as a guide for proper calcar screw insertion. UB-ECH should be 3 mm above UB-PMT and three-fourths of cases achieved proper calcar screw location.

Presence of incomplete superficial axillary arch and pectoralis quartus muscle in one male body / Presencia en un individuo de un arco axilar superficial incompleto y de un músculo pectoral cuarto

SUMMARY: The anatomical variations of the pectoralis major muscle (PMM) and latissimus dorsi muscle (LDM) range from agenesis to the presence of supernumerary fascicles with a variety of insertions and relationships with the muscles, fascia, vessels, nerves and skeletal components of the shoulder girdle and the axilla. Many of these variations are clinically irrelevant, but extremely interesting and revealing from the perspective of comparative anatomy, ontogeny, and phylogeny. In this report, we present two different supernumerary muscles in the chest of one adult male body, identified during dissection practice of undergraduate medical students at Universidad Surcolombiana. These supernumerary fascicles in the axillary region were caudal to the lower edge of the PMM on the right side of the chest, and in contact with the anterior edge of the LDM on the left side of the chest; each fascicle was inserted in the ipsilateral coracoid process. These observations are congruent with the pectoralis quartus muscle and an incomplete and superficial axillary arch, respectively.

RESUMEN: Las variaciones anatómicas del músculo pectoral mayor (MPM) y del músculo latísimo del dorso (MLD) van desde la agenesia hasta la presencia de fascículos supernumerarios con una variedad de inserciones y relaciones con los músculos, fascias, vasos, nervios y componentes esqueléticos de la cintura escapular y la axila. Clínicamente, muchas de las variaciones son irrelevantes, pero extremadamente interesantes y reveladoras desde la perspectiva de la anatomía comparada, la ontogenia y la filogenia. En este estudio, presentamos dos músculos supernumerarios diferentes en la pared torácica de un hombre adulto, identificados durante la práctica de disección de estudiantes de medicina de la Universidad Surcolombiana. Estos fascículos supernumerarios en la región axilar estaban caudales al margen inferior del MPM en el lado derecho del tórax y en contacto con el margen anterior del MLD en el lado izquierdo del tórax; cada fascículo se insertaba en el proceso coracoides ipsilateral. Estas observaciones son congruentes con el músculo pectoral cuarto y un arco axilar incompleto y superficial, respectivamente.

The Shoulder Trans-pectoralis Arthroscopic Portal Is a Safe Approach to the Arthroscopic Latarjet Procedure: A Cadaveric Analysis.

PURPOSE: To assess the proximity of neurovascular structures in a layered approach during medial portal placement and determine standardized measurements for establishing a portal medial to the coracoid used in arthroscopic Latarjet-type procedures. METHODS: Twelve shoulders (6 right and 6 left) in 6 fresh frozen cadaveric torsos were mounted in the modified beach-chair position. A standard posterior portal and 3 anterior portals-central, lateral, and medial-were used. A long spinal needle was placed along the path of the medial portal to the lateral tip of the coracoid, superficial to the conjoined tendon and pectoralis minor. A second long spinal needle was directed toward the medial base of the coracoid, penetrating the pectoralis minor. Superficial and deep plane dissections were performed, and distances to surrounding neurovascular structures were recorded. RESULTS: In the superficial plane, the cephalic vein and lateral pectoral nerve were located a mean distance (± standard deviation) of 4.6 ± 1.9 mm and 9.4 ± 2.6 mm from the spinal needle, respectively. In the deep plane, the axillary nerve was 24.9 ± 7.4 mm from the needle; the lateral cord of the brachial plexus, 25.5 ± 8.1 mm; the axillary artery, 34.1 ± 6.0 mm; and the musculocutaneous nerve, 42.2 ± 9.2 mm. The portal was consistently established 45.0 to 50.0 mm distal and 30.0 to 35.0 mm medial to the coracoid, which was a minimum distance of 10 mm to the lateral pectoral nerve. CONCLUSIONS: In a cadaveric model, the creation of a medial trans-pectoralis major portal used in the arthroscopic Bankart-Bristow-Latarjet procedure can avoid compromise of vital neurovascular structures, alleviating concerns of creating a portal medial to the coracoid. Portal placement 45.0 to 50.0 mm distal and 30.0 to 35.0 mm medial to the palpable tip of the coracoid process may be a safe approach to perform the arthroscopic Bankart-Bristow-Latarjet procedure. CLINICAL RELEVANCE: Creation of a portal medial to the level of the coracoid may pose a risk to neurovascular structures. This cadaveric study establishes a working zone for medial trans-pectoralis portal placement, which avoids vital neurovascular structures, and provides standardized measurements for establishing this portal for use in the arthroscopic Bankart-Bristow-Latarjet procedure.

The human costal cartilage: Anatomical and radiological study of macro-vascularization and micro-vascularization and its clinical relevance regarding vascularized chondrocostal free flap surgery.

INTRODUCTION: Cartilage repair usually involves in non-vascularized osteochondral or chondral grafts with some drawbacks potentially linked to the lack of vascular supply in those grafts. The aim of this study was to describe a surgical approach for harvesting a vascularized chondrocostal graft, to study the vascular supply to the perichondrium and finally to describe the perichondrium micro-vascularization in order to know how such grafts could be used in cartilage repair surgery. MATERIALS AND METHODS: We harvested and studied 18 costal cartilages harvested from 12 fresh anatomical subjects. The anatomic pieces were injected with a radio-opaque tracer, analyzed macroscopically, then a plain X-rays and CT scan analysis with three-dimensional rendering was performed in order to evaluate the characteristics of the different patterns of their vascularization. RESULTS: The surgical approach to harvest a vascularized 5th chondrocostal graft is explained in detail. All of the cartilages were vascularized by the internal thoracic artery and harvested with a pedicle of an average length of 34mm and diameter of 2.14mm. In all specimens, perichondrium vascularization arises from both superior and inferior intercostal branches. Anastomoses between inferior and superior intercostal branches are always found in all specimens at the level of the epichondrium. CONCLUSIONS: The anatomic approach for harvesting a vascularized chondrocostal graft is simple and only slightly differs from the approach described for harvesting a non-vascularized chondrocostal graft. The vascular supply to the perichondrium of such a vascularized chondrocostal graft is sustained by the internal thoracic vessels which have a sufficient diameter and length to allow easy micro-anastomosis. The organization of the micro-vasculature within the perichondrium allows the graft to be tailored to a large cartilage defects and also to small bipolar cartilage defects.

Pectoralis major tendon and enthesis: anatomic, magnetic resonance imaging, ultrasonographic, and histologic investigation.

BACKGROUND: This study evaluates the pectoralis major (PM) tendon humeral insertion, using imaging and histologic assessment in cadaveric specimens. Current descriptions of the pectoralis major tendon depict a bilaminar enthesis, and clarification of the anatomy is important for diagnostic and surgical considerations. MATERIALS AND METHODS: Fourteen fresh-frozen whole upper extremity specimens were used in this study. Magnetic resonance (MRI) and ultrasonographic (US) imaging of the PM muscles, tendons, and entheses were performed, followed by anatomic dissection and inspection. Morphology of the lateral tendon and entheses were evaluated, focused on the presence of layers. In 11 specimens, the lateral 3 cm of the PM tendon was carefully dissected from the footprint, whereas in 3 specimens, the tendon and humeral insertion were preserved and removed en bloc. Histology was performed in axial slabs along the medial-lateral length of the tendon and also evaluated for the presence of layers. RESULTS: The superior-inferior and medial-lateral lengths of the PM footprint were 75 ± 9 mm and 7 ± 1 mm respectively. In all specimens, the clavicular and sternal head muscles and tendons were identified, with the clavicular head tendon generally being shorter. The medial-lateral length of the clavicular head tendon measured 19 ± 8 mm superiorly and 9 ± 3 mm inferiorly. The medial-lateral length of the sternal head tendon measured 38 ± 8 superiorly and 41 ± 18 mm inferiorly. All specimens demonstrated a unilaminar, not bilaminar, enthesis with abundant fibrocartilage on histology. Three specimens demonstrated interspersed entheseal fat and loose connective tissue at the enthesis on MRI and histology. CONCLUSION: The PM tendon humeral insertion consists of a unilaminar fibrocartilaginous enthesis. US, MRI, and histology failed to identify true tendon layers at the enthesis. Delaminating injuries reported in the literature may originate from a location other than the enthesis.

Perforator Flaps Based on the Terminal Perforators of the Pectoral Branch of Thoracoacromial Vessels Axis: A Viable Option in the Head and Neck Reconstructions.

BACKGROUND: The purpose of this article is to develop a new method for elevating the pedicled terminal pectoral perforator flaps (PTPPFs) and to resolve the difficulties and controversies that shroud the anatomy of terminal pectoral perforators from the pectoral branch of the thoracoacromial axis. AIM: Anatomical study was conducted to assess the feasibility of perforator flaps based on the terminal perforators of the pectoral branch of the thoracoacromial vessel axis. The knowledge that gleaned from this anatomical study was applied in the clinical scenario. A clinical retrospective study was conducted to evaluate the outcome of PTPPFs for the reconstruction of postexcisional head and neck defects. MATERIALS AND METHODS: Thirty cadaveric specimens were examined for the anatomy of the terminal musculocutaneous pectoral branch perforators. Thirty-two cases (22 males, 10 females) of various head and neck postexcision defects were reconstructed with the PTPPFs in a single-stage manner. Pectoralis major muscle with its innervation was spared in all cases. All the secondary defects were closed primarily. RESULTS: The maximum cutaneous paddle size was 156 cm harvested on a single best terminal pectoral branch perforator. The average size of the cutaneous paddle harvested was 73.47 cm. The flap complications noted (9.3%) were trivial, and all the flaps survived well. The average institutional computed score for esthetic and functional recovery at the donor and reconstructed site done by 2 independent observers were 4.56 and 3.78, respectively. CONCLUSIONS: The recruitment of the chest skin on the terminal pectoral branch perforators resulted in a long pedicle flap with adequate qualities like color match, texture match, and pliability. This flap shall serve as a primary option for pedicle and free flap head and neck reconstructions.

Expresión morfológica del músculo axilopectoral: un estudio anatómico directo en una muestra de población colombiana / Morphological expression of the axillary pectoral muscle: a direct anatomical study in a sample of Colombian population

El músculo axilopectoral (MAP) es una estructura fibromuscular accesoria de la región axilar, que se relaciona con el plexo braquial, vasos y linfonodos axilares, y es reportado en los diferentes grupos poblacionales con incidencia variable. Se evaluaron un total de 106 axilas correspondientes a 53 cadáveres frescos que fueron sometidos a autopsia. El MAP se presentó en 5 regiones axilares (4,7 %), con tres casos unilaterales (2,8 %) y uno bilateral (0,9 %). La longitud total del MAP estuvo en un rango de 81,6-119,7 mm, mientras que su segmento tendinoso midió 13,3-28,1 mm. El espesor de su vientre muscular fue de 7,1-52 mm y del tendinoso 6,920,1 mm. En todos los casos, el MAP se originó del músculo latísimo del dorso y se insertó en el labio lateral del surco intertubercular del húmero, adyacente a la inserción del músculo pectoral mayor. Los MAP evaluados fueron inervados por el nervio toracodorsal. En dos casos, el vientre muscular del MAP cursó con trayectoria antero medial a las fibras infraclaviculares del plexo braquial, mientras que en los tres restantes, los segmentos fibrosos de inserción del MAP estuvieron relacionados con el plexo. La incidencia del MAP encontrada en el presente estudio es similar a los reportes previos realizados en cadáveres y considerablemente mayor a los reportes anatomoquirúrgicos. La importancia del MAP radica en su implicación con el síndrome de salida torácica, trombosis profunda del miembro superior y en las complicaciones en la linfadenectomía axilar.

The axillary pectoral muscle (APM) is an accessory fibromuscular structure of the axillary region. It is related to the brachial plexus, axillary vessels and lymph nodes, and is reported with variable incidence in different population groups. A total of 106 axilla were evaluated corresponding to 53 fresh cadavers. The APM was presented in 5 axillary regions (4.7 %), with three unilateral cases (2.8 %) and one bilateral (0.9 %). The total length of the APM ranged from 81.6-119.7 mm, while its tendinous segment measured 13.3-28.1 mm. Muscular belly thickness was 7.1-52 mm and the tendinous segment measured 6.9-20.1 mm. In all cases, the APM originated from the latissimus dorsi muscle and inserted into the lateral lip of humerus intertubercular sulcus, adjacent to the pectoralis major muscle insertion. The evaluated APMs were innervated by the thoracodorsal nerve. In two cases, the APM muscular belly had an anterior medial trajectory to brachial plexus fibers, while in the remaining samples, long fibrous segments of APM insertion were related to the plexus. The incidence of the APM found in the present study is similar to previous reports carried out in cadavers; it was considerably higher than previous anatomy-surgical reports. The importance of APM relies on its involvement with thoracic outlet syndrome, deep thrombosis of the upper limb and complications in axillary lymphadenectomy.

Incidence of sternalis muscle in the Caldas population (Colombia): anatomical variations / Incidencia del músculo esternal en la población de Caldas (Colombia): variaciones anatómicas

The musculus sternalis is an anatomical variant that occurs in 3-8 % of the world population and its incidence is higher in women. It can be found unilaterally or bilaterally and is located in the anterior wall of the thorax, where its fibers run parallel to the sternum and superficial to the medial part of the pectoralis major muscle. The main objective of this study was to quantify the incidence of musculus sternalis in the population of Caldas (Colombia) and, therefore, 68 cadavers of adult individuals were used during a period of twenty years to determine the incidence of this muscle and describe its anatomical characteristics. Two cadavers had this muscle, which was equivalent to 2.94 % of the sample, where one was located unilaterally and in other bilaterally. In the case of unilateral presence, the muscle presented an oblique direction thatdoes not coincide with any subtype of the classification given for these muscles. In bilateral presentation, both muscles were continuous at their upper ends with the respective sternocleidomastoid muscle. In addition, the right musculus sternalis had a digastric shape, which also does not coincide with any subtype of the classification.

El músculo esternal es una variante anatómica que se presenta entre el 3 % y 8 % de la población mundial y su incidencia es mayor en mujeres. Puede hallarse de manera unilateral o bilateral y se localiza en la pared anterior del tórax, donde sus fibras corren paralelas al esternón y superficial a la región medial del músculo pectoral mayor. El objetivo del presente estudio fue cuantificar la incidencia del músculo esternal en la población de Caldas (Colombia). Fueron revisados 68 cadáveres de individuos adultos durante un lapso de doce años, con el fin de determinar el grado de presencialidad del músculo y sus características anatómicas. Dos cadáveres, que equivale al 2,94 % de la muestra, presentaron el músculo esternal, uno de manera unilateral y el otro bilateral, a los cuales se les hizo una descripción anatómica detallada. En la presentación unilateral, el músculo presentó una dirección oblicua que no coincide con ningún subtipo de la clasificación dada para estos músculos. En la presentación bilateral, ambos músculos se continúan por su extremo superior con el respectivo músculo esternocleidomastoideo. Además, el músculo esternal derecho tiene una configuración digástrica, que tampoco coincide con ningún subtipo de la clasificación.

How to Use Pectoral Nerve Blocks Effectively­An Evidence-Based Update

Since the original description in 2011, the array of pectoral nerve blocks has evolved. The pectoral nerve (PECS) block in conjunction with general anesthesia can decrease an additional analgesic in perioperative period for breast cancer surgeries. Current literature on the PECS block has reported 3 several types (PECS I, PECS II, and serratus plane blocks). The PECS I block is the same as to the fi rst injection in the PECS II block. The second injection in the PECS II block and the serratus plane block blocks intercostal nerves (Th2­6) and provides an analgesic for the breast cancer surgery. However, the PECS I block (or fi rst injection in the PECS II block) has no analgesic, because both lateral and medial pectralis nerve blocks are motor nerves. PECS block in previous reports, when added to opioid-based general anesthesia, may improve analgesia and decrease narcotic use for breast cancer surgery. Moreover, PECS block compares favorably with other regional techniques for selected types of surgery. A major limitation of the PECS block is that it cannot block the internal mammary region. Therefore, some studies have reported its ability to block the anterior branches of the intercostal nerve. PECS block is an effective analgesic tool for the anterolateral chest. In particular, the PECS block can provide more effective analgesia for breast cancer surgery.

Pectoralis Major Muscle Free Flap: Anatomical Studies on Pedicle Length and Vessel Diameter.

Large and deep defects resulting from lateral skull base surgery represent a challenge to the head and neck surgeon. Different microvascular free flaps have specific advantages and disadvantages. While the pedicled pectoralis major flap is considered a "work horse," it comes with a rather short pedicle. The aim of this study was to analyze the vascular anatomy of the pectoralis major flap and assess its suitability for microvascular transfer. Anatomical studies have been performed on 6 Thiel-fixed cadavers allowing a harvest of 12 flaps by the same surgeon. Measurements of the pedicle's length and vessel diameters have been taken with a ruler and caliper. The mean pedicle length and mean diameters (Ø) of the thoracoacromial artery and concomitant vein were found to be 9.8 cm, Ø 4.2 mm, and Ø 4.9 mm, respectively. These results suggest the potential utility of a free pectoralis major flap with microvascular anastomosis.

Description of the chondroepitroclearis muscle and its relationship to the median nerve in a Korean corpse / Descripción del músculo condroepincondilar medial y su relación con el nervio mediano en un cadáver coreano

SUMMARY: Anomalous muscle slips of pectoralis major have been reported on several cases in the literature. Among these, chondroepitroclearis muscle is an extremely rare aberrant muscular slip originating from the pectoral region. During an educational dissection, chondroepitroclearis muscle was found on the right side in a Korean cadaver. Tendinous muscular slip originated from pectoralis major muscle, crossing the neurovascular bundle in the arm, and inserted onto medial epicondyle of the humerus. Clinical significance of these anomalous slip can cause median nerve entrapment and functionally limited movement of the humerus. We report a case of tendinous chondroepitroclearis muscle and discuss its clinical and embryological significance.

RESUMEN: En la literatura se han reportado fascículos anómalos del músculo pectoral mayor. Entre estos, el condroepicondilar medial es un fascículo muscular aberrante extremadamente raro que se origina en la región pectoral. Durante una disección educativa, se encontró esta variación en el lado derecho de un cadáver coreano. El fascículo muscular tendinoso se originó a partir del músculo pectoral mayor, cruzando el paquete neurovascular en el brazo, y se insertó en el epicóndilo medial del húmero. La importancia clínica de estos fascículos anómalos radica en la posibilidad de causar el atrapamiento del nervio mediano, causando un movimiento funcionalmente limitado del húmero. Divulgamos un caso de músculo condroepicondilar medial tendinoso y discutimos su significado clínico y embriológico.

Classification of unusual insertion of the pectoralis minor muscle.

PURPOSE: The pectoralis minor muscle (PMi) generally originates from the third, fourth, and fifth ribs and inserts on the medial and superior margins of the anterior portion of the coracoid process. Variations in the shape and attachment point of the PMi could cause discomfort in the shoulders. The aim of this study was to observe the types of morphological insertion patterns and attachment sites of the PMi. METHODS: Seventy-four sides of fresh, embalmed Korean (42 sides; mean age 78 years) and Thai (32 sides; mean age 78 years) cadavers were dissected to analyze the morphological insertion types and attachment sites of the PMi. RESULTS: Unusual insertion patterns were evident in about 23% of the samples. When the portion of the PMi tendon ran over the coracoid process, the most common attachment site was the glenohumeral joint capsule. We also confirmed the attachment of the PMi to the clavicle. Costal attachments of the PMi that extend from the second rib to the fourth rib were observed frequently as well. CONCLUSIONS: Unusual insertion patterns of the PMi are common. Some authors consider that tendon attachment to the joint capsule can cause shoulder pain. In addition, the PMi tendon could be utilized in acromioclavicular joint reconstruction. Surgeons need to be aware of the possibility of a PMi variant being found during surgery even when this is not visible in magnetic resonance or ultrasound imaging.

Evidence of the sternalis muscle in two South African cadavers.

The sternalis muscle is an infrequent, non-pathological anatomical variant typically misrepresented in a clinical context. It presents with 3-8% prevalence, according to cadaveric studies. The muscles were identified during routine cadaver prosection at the School of Anatomical Sciences, University of the Witwatersrand. Here, we report two cases of the sternalis muscle in two South African White cadavers. Analysis of the sternalis muscles revealed unilaterally present, distinctly defined muscle masses on the right (case number 1, female) and left (case number 2, male) hemithorax, lateral to the sternum. The muscles occurred with a prevalence of 2.25% within the cadaveric population examined. The prevalence of the sternalis muscle is generally low, especially in the European population. Their presence represents the remnants of the cutaneous muscles in the ventral thorax of lower animals. Clinically, the sternalis muscle may be misinterpreted as a pathological mass or lesion, thus accurate knowledge regarding its variations and prevalence is of importance.

Pectoralis Major Tendon Insertion Anatomy and Description of a Novel Anatomic Reference.

Pectoralis major rupture is an uncommon injury often treated surgically, requiring anatomic knowledge of the tendon insertion. This study defines the pectoralis major tendon insertion footprint and a novel anatomic relationship. Twelve cadaver shoulders were evaluated andmeasured using a standard surgical ruler to demonstrate the normal anatomic footprint. Measurements were taken from the anterior medial margin of the articular surface of the humeral head to the superior margin of the pectoralis major insertion and its relation to the latissimus dorsi tendon insertion. The average length and width of the pectoralis major insertion were 73.3 ± 10.0 mm and 3.3 ± 0.54 mm, respectively, consistent with previous publications. On average, the superior margin of the pectoralis tendon was within 1 mm of the latissimus dorsi insertion and 41.2 ± 9.27 mm from the articular margin. These points form a new anatomic reference of the latissimus dorsi, providing an intraoperative reference point when performing pectoralis major muscle tendon repair. (Journal of Surgical Orthopaedic Advances 27(1):39-41, 2018).

Quantitative Assessment of the Coracoacromial and the Coracoclavicular Ligaments With 3-Dimensional Mapping of the Coracoid Process Anatomy: A Cadaveric Study of Surgically Relevant Structures.

PURPOSE: To perform a quantitative anatomic evaluation of the (1) coracoid process, specifically the attachment sites of the conjoint tendon, the pectoralis minor, the coracoacromial ligament (CAL), and the coracoclavicular (CC) ligaments in relation to pertinent osseous and soft tissue landmarks; (2) CC ligaments' attachments on the clavicle; and (3) CAL attachment on the acromion in relation to surgically relevant anatomic landmarks to assist in planning of the Latarjet procedure, acromioclavicular (AC) joint reconstructions, and CAL resection distances avoiding iatrogenic injury to surrounding structures. METHODS: Ten nonpaired fresh-frozen human cadaveric shoulders (mean age 52 years, range 33-64 years) were included in this study. A 3-dimensional coordinate measuring device was used to quantify the location of pertinent bony landmarks and soft tissue attachment areas. The ligament and tendon attachment perimeters and center points on the coracoid, clavicle, and acromion were identified and subsequently dissected off the bone. Coordinates of points along the perimeters of attachment sites were used to calculate areas, whereas coordinates of center points were used to determine distances between surgically relevant attachment sites and pertinent bony landmarks. RESULTS: The CAL had a single consistent acromial attachment (mean area 77 mm [51.9, 102.2]) and then bifurcated into 2 bundles, anterior and posterior, that separately inserted on the lateral aspect of the coracoid. The footprint areas were 54.4 mm2 [31.7, 77.2] and 30.6 mm2 [23.4, 37.7] for the anterior and posterior CAL bundles, respectively. These anterior and posterior bundles attached 10.6 mm [8.4, 12.9] and 24.8 mm [12.3, 27.4] medial and proximal to the apex of the coracoid process, respectively. The minimum distance between the coracoid apex and the trapezoid ligament was 25.1 mm [22.1, 28.1] and was noted to be different in males (28.1 mm [25.1; 31.2]) and females (22.0 mm [18.2, 25.9]). The most lateral insertion of the CC ligaments on the clavicle the AC joint was 15.7 mm [13.1, 18.3]. The distance between the most medial to the most lateral point of the CC ligaments on the clavicle was 25.6 mm [22.3, 28.9], which accounted for 18.2% [15.8, 20.6] of the clavicle length. CONCLUSIONS: In contrast to previous findings, 2 different coracoid attachments (anterior and posterior bundles) of the CAL were consistently identified in all specimens. Moreover, a coracoid osteotomy for a bone graft for the Latarjet procedure should be performed at less than 28.1/22 mm from the apex of the coracoid in male/female patients, respectively. The CC ligaments' attachments on the clavicle were located 15.7 mm from the AC joint, which should be considered for reconstruction. CLINICAL RELEVANCE: During the Latarjet technique, to maintain the integrity of the CC ligaments, precise knowledge of differences between male and female anatomy is necessary during a coracoid osteotomy. Furthermore, when reconstructing the AC joint, the distance from the lateral aspect of the clavicle and the size of the attachments areas should be considered to better replicate the native anatomy.

Qualitative and Quantitative Anatomy of the Proximal Humerus Muscle Attachments and the Axillary Nerve: A Cadaveric Study.

PURPOSE: To provide a quantitative and qualitative anatomic analysis of the pectoralis major, teres major, and latissimus dorsi on the humerus, as well as the deltoid tendinous attachments on the proximal humerus and acromion, and to quantitatively characterize the humeral course of the axillary nerve. METHODS: Ten nonpaired, fresh-frozen human cadaveric shoulders were analyzed. A portable coordinate-measuring device quantified the location of bony landmarks and tendon attachment areas. The tendon footprints were recorded by tracing their outlines and center points. The footprint areas of the tendons, the distances between the footprint areas and pertinent osseous and soft-tissue landmarks, and the distance between where the axillary nerve courses across the humerus relative to the acromion and greater tuberosity were measured. RESULTS: Of the 10 specimens, 9 (90%) had 5 distinct tendinous bands attaching the deltoid to the acromion; 1 specimen had 4 bands. The distances between the center of the deltoid footprint on the humerus and the centers of the pectoralis major, latissimus dorsi, and teres major tendon footprints on the humerus were 43.5 mm, 58.5 mm, and 49.4 mm, respectively. The shortest distances from the perimeter of the pectoralis major to the latissimus dorsi and teres major tendon footprints were 3.9 mm and 9.5 mm, respectively. The distance from the superior aspect of the greater tuberosity to the axillary nerve on the humeral shaft was 50.3 mm (95% confidence interval, 47.0-53.5 mm). The distance from the lateral acromion to the axillary nerve was 69.3 mm (95% confidence interval, 64.1-74.5 mm). CONCLUSIONS: The deltoid muscle had 4 to 5 tendinous insertions on the acromion, and the axillary nerve was 50.3 mm from the tip of the greater tuberosity. The distance between the lower border of the pectoralis major and the axillary nerve was 9.4 mm. CLINICAL RELEVANCE: Knowledge of the quantitative anatomy of the tendons of the proximal humerus and axillary nerve can aid in identifying structures of interest during open shoulder surgery and in avoiding iatrogenic axillary nerve injury. Furthermore, this study provides direction to avoid injury to the deltoid tendons during open surgery.

Muscle thickness of the pectoralis major and rectus abdominis and level of physical activity in chronic hemodialysis patients / Espessura muscular do pectoralis major e do rectus abdominis e nível de atividade física em pacientes em hemodiálise crônica

Abstract Introduction: Patients on chronic hemodialysis tend to lose lean body mass and have sedentary behavior. Objective: To compare the level of physical activity and the morphology of the muscles pectoralis major and rectus abdominis of patients on hemodialysis with healthy subjects. Methods: We studied 17 patients and 17 healthy individuals. Muscle thickness were evaluated by ultrasound, and the level of physical activity by the International Physical Activity Questionnaire (IPAQ), long version. Results: The patients had lower thicknesses of the pectoralis major (5.92 ± 0.35 mm vs. 8.35 ± 0.62 mm, p < 0.001) and rectus abdominis (0.96 ± 0.10 mm vs. 2 21 ± 0.40 mm, p < 0.001) compared to healthy subjects. Patients were physically less active than healthy individuals: 1502.55(788.19-2513.00) MET-minutes/week vs. 2268.0(1680.0-4490,8) MET-minutes/week (p = 0.006); the weekly caloric expenditure of patients was also lower: 1384.0(480,7-2253.7) kcal/kg/week vs. 1680.0(1677.4-4950.0) kcal/kg/week (p = 0.010). The average time spent sitting per week of the patients was higher than in healthy subjects (394.0 ± 33.1 min/day vs. 293.0 ± 38.6, p = 0.009) as well as the average time spent sitting during weekend (460.0 ± 40.1 vs. 201.0 ± 10.7, p = 0.003). Conclusion: Chronic renal failure patients on hemodialysis have sedentary behavior and lower muscle thickness of the trunk.

Resumo Introdução: Pacientes que realizam hemodiálise crônica tendem a perder massa magra e ter comportamento sedentário. Objetivo: Comparar o nível de atividade física e morfologia dos músculos peitoral maior e reto do abdômen de pacientes que realizam hemodiálise com indivíduos saudáveis. Métodos: Foram estudados 17 pacientes e 17 indivíduos saudáveis. As espessuras musculares foram avaliadas por meio de ultrassonografia, e o nível de atividade física pelo Questionário Internacional de Atividade Física versão longa (IPAQ). Resultados: Os pacientes apresentaram menores espessuras do peitoral maior (5,92 ± 0,35 mm vs. 8,35 ± 0,62 mm, p < 0,001) e de reto abdominal (0,96 ± 0,10 mm vs. 2,21 ± 0,40 mm, p < 0,001) comparados aos sujeitos saudáveis. Os pacientes foram fisicamente menos ativos que os indivíduos saudáveis: 1502.55(788.19-2513.00) MET-minutos/semana vs. 2268.0(1680.0-4490,8) MET-minutos/semana (p = 0,006); o gasto calórico semanal dos pacientes também foi menor: 1384,0(480,7-2253.7) kcal/kg/semana vs. 1680,0(1677,4-4950,0) kcal/kg/semana (p = 0,010). O tempo médio gasto sentado por semana dos pacientes foi maior que dos sujeitos saudáveis (394,0 ± 33,1 min/dia vs. 293,0 ± 38,6, p = 0,009), assim como o tempo médio gasto sentado durante o fim de semana (460,0 ± 40,1 vs. 201,0 ± 10,7, p = 0,003). Conclusão: Pacientes renais crônicos em hemodiálise apresentam comportamento sedentário e menores espessuras musculares do tronco.

Muscular anatomy of the pectoral girdle and forelimb of Iguana i. iguana (Squamata: Iguanidae) / Anatomia muscular do cíngulo peitoral e membro torácico de Iguana i. iguana (Squamata: Iguanidae)

Green iguana has arboreal and terrestrial habits. It is widely distributed in Central and South America, inhabiting several biomes in Brazil. Some researches were focused on this species, however, morphological information are still limited. With that in sight, we aimed to add data to the anatomical knowledge. Two post mortem specimen of Iguana i. iguana were acquired, donated by a scientific breeding, and dissected. To describe the muscles we refuted the skin and removed the fascias, individualizing the muscles. We identified the following muscles: pectoralis, deltoideus clavicularis, deltoideus scapularis, trapezius, latissimus dorsi, coracobrachialis brevis, coracobrachialis longus, serratus thoracis, levator scapulae, biceps brachii and triceps brachii. Some of them, like coracobrachialis brevis, present conservative anatomy, originating from the ventral surface of the coracoid and inserting onto the proximal humerus. Some, like trapezius and biceps brachii, are similar to other reptile species, trapezius takes its origin from the thoracodorsal fascia and biceps arises by two heads and inserts on the radial tuberosity. Deltoideus clavicularis and deltoideus scapularis share a common insertion tendon. Pectoralis varies its origin and divisions, however, the insertion always occur on the deltopectoral crest. Triceps brachii is comprised of four heads. Its long medial head originates via a tendinous arc, feature described only in crocodilians. We conclude that Iguana i. iguana forelimb musculature is similar to other reptiles, presenting its own characteristics that reflect its habits.

Iguanas verdes tem hábitos arbóreos, terrestres e aquáticos, e são totalmente herbívoras. Tem ampla distribuição na América Central e do Sul, habitando vários biomas no Brasil. Investigações diversas tiveram esta espécie como foco, embora informações morfológicas sejam ainda escassas. Objetivando adicionar dados ao conhecimento anatômico, dois espécimes de Iguana i. iguana foram obtidos post mortem, por doação de um criadouro científico, e dissecados. Os músculos foram individualizados para identificação e descrição das origens, inserções e características. Alguns músculos, como o coracobraquial curto, apresentam morfologia conservativa, sua origem ocorre na superfície ventral do coracóide e inserção na epífise proximal do úmero. O trapézio, o bíceps braquial e o deltóide clavicular se apresentam similares à outros répteis, com a origem do trapézio na fáscia toracodorsal e o bíceps, com duas cabeças, se inserindo no tubérculo do rádio. O deltóide clavicular possui o tendão de inserção unido ao do músculo deltóide escapular. O músculo peitoral apresenta variações em sua origem e divisões, mas a inserção sempre ocorre na crista deltopeitoral. A origem da cabeça longa caudal do tríceps ocorre por meio de arco tendíneo, característica antes descrita apenas em crocodilianos. A musculatura de Iguana i. iguana se apresenta similar à de outros répteis no geral, com características próprias refletindo seus hábitos.

In Vivo Analysis of Biceps Tendon Characteristics in Subpectoral Tenodesis.

PURPOSE: To report the in vivo characteristics of the long head of the biceps tendon (LHBT); to evaluate the relation of age, gender, height, weight, and body mass index to the length and sutured and tubularized diameter of the LHBT; and to determine the smallest possible tunnel diameter for a subpectoral biceps tenodesis (SPBT) that can accommodate most patients. METHODS: The study included 66 patients (33 men and 33 women) with an average age of 54 years (range, 29-73 years) undergoing SPBT. After tenotomy, the length from the biceps musculotendinous junction to the released end was measured. The tendon was transected 3 cm proximal to the musculotendinous junction and sutured, and the diameter was measured. The depth of the reamed tunnel was recorded. RESULTS: The average tendon length was 84.0 mm, measuring 91.9 mm in men and 76.2 mm in women (P < .001), and the average tendon diameter was 4.4 mm, varying slightly between men (4.5 mm) and women (4.3 mm) (P < .001). Mean bone tunnel depth was 17.5 mm, with 19 mm in men and 16.1 mm in women (P < .001). Patient height showed a significant relation to both tendon length and tendon diameter. Weight was not correlated with tendon diameter but did show a significant relation to tendon length. CONCLUSIONS: We have characterized the in vivo length and diameter of the LHBT at the time of an SPBT. Our findings have shown that there was a statistically significant gender difference in tendon length and diameter, but the diameter of the sutured tendon, which was placed into the tunnel, averaged 4.4 mm and ranged from 3.5 to 5 mm for all ages, both genders, all heights, and all weights. This finding is clinically relevant in that a small tunnel measuring 5.5 mm or less is sufficient to perform an SPBT. LEVEL OF EVIDENCE: Level IV, case series, anatomic study.