A proposal for a new classification of coracobrachialis muscle morphology.

INTRODUCTION: The coracobrachialis muscle (CRM) originates from the apex of the coracoid process, in common with the short head of the biceps brachii muscle, and from the intermuscular septum. It inserts to the medial part of the humerus between the attachment of the medial head of the triceps brachii and the brachial muscle. Both the proximal and distal attachments of the CRM, as well as its relationship with the musculocutaneus nerve, demonstrate morphological variability. MATERIAL AND METHODS: One hundred and one upper limbs (52 left, and 49 right) fixed in 10% formalin solution were examined. RESULTS: Three main types, with subtypes, were identified. The most common was Type I (49.5), characterized by a single muscle belly with a classical origin from the coracoid process, medially and posteriorly to the tendon of the biceps brachii. Type II (42.6%), characterized by two heads, was divided into two subtypes (A-B) depending on its origin: Type IIA, where one head originated from the coracoid process posteriorly to the tendon of the biceps brachii and the second head from the short head of the biceps brachii, and Type IIB, in which both heads originated from the coracoid process; however, the superficial head fused with the insertion of a short head of the biceps brachii, while the deep head was directly originating. Finally, Type III (7.9%) was characterized by three heads: two originated from the coracoid process (superficial and deep), and the third from a short head of the biceps brachii. Two types of insertion and two types of musculocutaneous nerve (MCN) relative to CRM could be distinguished. CONCLUSION: An adapted classification is needed for all clinicians working in this area, as well as for anatomists. The CRM demonstrates morphological variability in both its proximal and distal attachments, as well as the variable course of the MCN relative to the CRM. WHAT IS KNOWN ABOUT THIS SUBJECT "AND" WHAT THIS STUDY ADDS TO EXISTING KNOWLEDGE: Not much is known about the variability of coracobrachialis muscle. The present paper introduces a completely new classification, both clinical and anatomical.

Incidence of anatomical variations according to the International Frontal Sinus Anatomy Classification (IFAC) and their coincidence with radiological sings of opacification.

BACKGROUND: The endonasal access to the frontal recess and sinus may be complicated by a variety of anatomical variations. Previous classifications of these variants were characterized by proper names or position information without anatomical reference. The IFAC is intended to simplify the classification of anatomical variations of the frontoethmoidal complex. The aim of this study was to analyse a representative number of sinus CT scans to assess the incidence of anatomical variations according to the IFAC and to compare the results with previous classifications. In addition, the coincidence of complex anatomical variations and radiological sings of opacification was investigated. METHODOLOGY/PRINCIPAL: Two hundred and forty-nine sinus CT scans were analysed in multiplanar reconstructions. Exclusion criteria were previous operations on the paranasal sinuses, malignant diseases, and an insufficient image quality. All anatomical variants were analysed according to the IFAC criteria. In addition, the coincidence of radiological sings of opacification and the presence of anatomical variations of the frontal recess and sinus were investigated. RESULTS: The analysis revealed Agger nasi cells in 95% of the CT scans. Supra agger cells (SACs) were detected in 49% and Supra agger frontal cells (SAFCs) in 25% of the data sets. Suprabulla cells (SBCs) were detected in 89% and Supra bulla frontal cells (SBFCs) in 27% of the scans. Supraorbital ethmoid cells (SECs) were detectable in 9% and interfrontal septal cells in 28% of the scans. Despite a partially strong narrowing of the frontal recess, no increased occurrence of radiological sings of opacification could be detected (p > 0.05). CONCLUSIONS: Anatomical variations in the frontoethmoidal area are very common. According to the IFAC criteria, in 43% of the patients, cells could be detected with pneumatization to or into the frontal sinus. The IFAC is structured more clearly compared to previous classifications due to the anatomical aspect. It represents the most consistent classification regarding surgical planning. Further studies will demonstrate the scientific and clinical value of this classification.

Revised, Computed Tomography-Based Lekholm and Zarb Jawbone Quality Classification.

PURPOSE: To propose a revised Lekholm and Zarb classification that takes into account all possible combinations of compact and trabecular bone and to provide guidelines for increased reproducibility of the classification. MATERIALS AND METHODS: Three new classes were added to the previous classification. The new classes have been designated as subclasses of bone types 2 and 3, as follows: Type 2b: Thick layer of compact bone surrounding a core of medium-density trabecular bone; Type 2c: Thick layer of compact bone surrounding a core of low-density trabecular bone; and Type 3b: Thin layer of compact bone surrounding a core of medium-density trabecular bone. Three interpretation guidelines were recommended to increase the reproducibility of the revised classification. Three experienced examiners were trained using the revised classification and provided with computed tomography (CT) sectional images of edentulous jawbones for classification. Each examiner classified the images twice with at least a 1-week interval. The intra-observer agreement was measured. RESULTS: The kappa statistic for the intra-observer agreement of the examiners ranged from 0.835 to 0.919 (P < .001). CONCLUSION: The high reproducibility of the proposed revised CT-based Lekholm and Zarb classification obtained in the current study suggests its efficacy in distinguishing between the various combinations of compact and trabecular bone.