The reason why scapulas are so flat is so that there is lots of room for muscles to attach. The ridge along the middle scapula is called the spine which is a pretty stupid name because it could get confused with the animal's actual spine. Deer and sheep have different lives.
What are the bones of the scapula?
Scapula: More commonly known as the shoulder blade, the scapula is a flat triangular bone located in the upper back. It connects with the collarbone at the front of the body. Humerus: The largest bone of the arm, the humerus connects to the scapula and clavicle in the shoulder. What does the scapula bone protect? The scapula is a strong bone ...
What is the function of the scapula?
- Function: fixes the scapula into the thoracic wall, and aids in rotation and abduction of the arm (90 to 180 degrees)
- Origin: Surface of the upper eight ribs at the side of the chest
- Insertion: Along the entire anterior length of the medial border of the scapula
- Innervation: Long thoracic nerve (C5, C6, C7)
Where is the spine of the scapula?
The spine of the scapula or scapular spine is a prominent plate of bone, which crosses obliquely the medial four-fifths of the scapula at its upper part, and separates the supra- from the infraspinatous fossa . Contents 1 Structure 1.1 Root 2 Function 3 Additional image 4 References 5 External links Structure
What is the scapula and where is it located?
The scapula, better known as the shoulder blade, is a triangular bone that serves as a joining force between the clavicle and the humerus. This bone is located posteriorly (on the back half of the body).
Is the scapula a flat bone?
Your scapula is a flat bone that's commonly referred to as your shoulder blade. You have two of these triangle-shaped bones in your upper back.
What makes a flat bone?
Flat bones are made up of a layer of spongy bone between two thin layers of compact bone. They have a flat shape, not rounded. Examples include the skull and rib bones. Flat bones have marrow, but they do not have a bone marrow cavity.
Is a scapula a long flat or irregular bone?
flat boneExplanation: The scapula is the only bone listed that is a flat bone. The ulna is a long bone, the sphenoid is an irregular bone, and the patella is a sesamoid bone.
What is the main purpose of flat bones?
Flat bones are bones whose principal function is either extensive protection or the provision of broad surfaces for muscular attachment. These bones are expanded into broad, flat plates, as in the cranium (skull), the ilium (pelvis), sternum and the rib cage.
What type of bone is the scapula?
The scapula is a flat, triangular-shaped bone (colloquially as the "shoulder blade"). It is located in the upper thoracic region on the dorsal surface of the rib cage. It connects with the humerus at the glenohumeral joint as well as the clavicle at the acromioclavicular joint to form the shoulder joint.
What is the process of flat bone formation called?
Intramembranous ossification is the characteristic way in which the flat bones of the skull and the turtle shell are formed. During intramembranous ossification in the skull, neural crest-derived mesenchymal cells proliferate and condense into compact nodules.
Which of the following are flat bones?
Note:The flat bones are the parietal, occipital, frontal, lacrimal, nasal, hip bone, vomer, ribs, sternum and scapulae.
What is the scapula?
Introduction. The scapula or shoulder blade is the bone that connects the clavicle to the humerus. The scapula forms the posterior of the shoulder girdle. It is a sturdy, flat, triangular bone. The scapula provides attachment to several groups of muscles.
What are all the flat bones in the body?
1. Flat Bones Protect Internal Organs. There are flat bones in the skull (occipital, parietal, frontal, nasal, lacrimal, and vomer), the thoracic cage (sternum and ribs), and the pelvis (ilium, ischium, and pubis). The function of flat bones is to protect internal organs such as the brain, heart, and pelvic organs.
Is the clavicle a flat bone?
The clavicle is a long bone of the body, not a flat bone. The clavicle is the collarbone, which is located in the upper part of the chest just under the neck. It connects the shoulder blade with the sternum, or breastbone, and allows the arm to hang down freely and away from the body.
Which bone has the same flat shape of the cranium or head?
There are eight cranial bones, each with a unique shape: Frontal bone. This is the flat bone that makes up your forehead. It also forms the upper portion of your eye sockets.
Where is compact bone found in flat bones?
Flat bones are formed by a thin layer of spongy bone tissue inside of which is located bone marrow. This spongy layer is then wrapped by two sheets (one for each side) of cortical or compact bone tissue. Examples of flat bones include the shoulder blades, sternum and bones of the skull and pelvis.
Which of the following is not a flat bone?
1. Which of the following is not a flat bone? The answer is C, Mandible. The mandible (lower jaw bone) is classified as an irregular bone.
What is not true about flat bones?
False. Flat bones are not found in the arms and the legs. Long bones are the bones which are found in the arms in the legs. Flat bones are the bones which compose the cranium pelvis and rib cage.
Is vertebrae a flat bone?
Examples of flat bones are the sternum (breast bone), ribs, scapulae (shoulder blades), and the roof of the skull (Figure 1). Irregular bones are bones with complex shapes. These bones may have short, flat, notched, or ridged surfaces. Examples of irregular bones are the vertebrae, hip bones, and several skull bones.
What type of ossification occurs in flat bones?
Intramembranous ossification directly converts the mesenchymal tissue to bone and forms the flat bones of the skull, clavicle, and most of the cranial bones.
What is the scapula?
Your scapula is a flat bone that’s commonly referred to as your shoulder blade. You have two of these triangle-shaped bones in your upper back. The muscles that allow your arms to rotate attach to your scapula.
What bone joins the scapula and the collar bone?
Your scapula also joins together with your collar bone and humerus bone in your upper arm to make your shoulder joint.
What bone attaches to the hip joint?
Your femur bones in your upper legs attach to your coxal bone to form your hip joint. It also provides an attachment point for several muscles, including your gluteal muscles.
What bone forms the space between your nostrils?
Vomer bone. This bone forms your nasal septum, the space between your nostrils.
What is flat bone?
Flat bones are a type of bone in your body. They’re typically thin, flattened, and slightly curved. Flat bones serve to either protect your internal organs or to provide a connection point for your muscles.
Which bone forms the back of the skull?
Occipital bone. This bone forms the back of your skull. It has an opening near the bottom that allows your spinal cord to meet your brain.
Which bone forms the upper portion of the eye socket?
Frontal bone. This bone forms your forehead and the upper portion of your eye sockets.
What is the scapula in anatomy?
FMA. 13394. Anatomical terms of bone. In anatomy, the scapula (plural scapulae or scapulas ), also known as the shoulder bone, shoulder blade, wing bone or blade bone, is the bone that connects the humerus (upper arm bone) with the clavicle (col lar bone). Like their connected bones, the scapulae are paired, ...
What does the prefix "scapula" mean?
The scapula forms the back of the shoulder girdle.
How many actions does the scapula perform?
Movements of the scapula are brought about by the scapular muscles. The scapula can perform six actions:
Why are scapular fractures rare?
Because of its sturdy structure and protected location, fractures of the scapula are uncommon. When they do occur, they are an indication that severe chest trauma has occurred. Scapular fractures involving the neck of the scapula have two patterns. One (rare) type of fracture is through the anatomical neck of the scapula. The other more common type of fracture is through the surgical neck of the scapula. The surgical neck exits medial to the coracoid process.
What is the upper picture of the thorax?
The upper picture is an anterior (from the front) view of the thorax and shoulder girdle. The lower picture is a posterior (from the rear) view of the thorax (scapula shown in red.) In anatomy, the scapula (plural scapulae or scapulas ), also known as the shoulder bone, shoulder blade, wing bone or blade bone, is the bone that connects the humerus ...
Where is the ridge on the scapula?
There is a ridge on the outer part of the back of the scapula . This runs from the lower part of the glenoid cavity, downward and backward to the vertebral border, about 2.5 cm above the inferior angle. Attached to the ridge is a fibrous septum, which separates the infraspinatus muscle from the Teres major and Teres minor muscles. The upper two-thirds of the surface between the ridge and the axillary border is narrow, and is crossed near its center by a groove for the scapular circumflex vessels; the Teres minor attaches here.
What are the three groups of muscles that attach to the scapula?
The scapula is a wide, flat bone lying on the thoracic wall that provides an attachment for three groups of muscles: intrinsic, extrinsic, and stabilising and rotating muscles . The intrinsic muscles of the scapula include the muscles of the rotator cuff —the subscapularis, teres minor, supraspinatus, and infraspinatus.
What is the scapula?
Rehabilitation. The scapula, better known as the shoulder blade, is a triangular bone that serves as a joining force between the clavicle and the humerus. This bone is located posteriorly (on the back half of the body). The scapula plays an important role in stabilizing the other bones involved in the rhythm of shoulder motion.
What is the function of the scapula?
Function. The scapula is responsible for several motions which are integral to daily movement and smooth upper extremity motion. Protraction and retraction of the scapula assist with movement of the pectoral girdle and chest muscles both forward and back, respectively.
What is the rhythm of the scapula and humerus?
The pattern of muscle contractions and motion that occurs between the scapula and the humerus is called the scapulohumeral rhythm , which is a large focus of physical therapy for shoulder pain.
What is the role of the scapula in the shoulder?
Similar to the scapulohumeral rhythm, this relationship is vital to the stability of the shoulder joint as a whole.
What causes shoulder impingement?
Shoulder impingement syndrome is partially caused by impaired scapular movements. This serves to place undue pressure on the nerves and blood supply running through the scapular muscles. When excessive pressure is placed on nerves over an extended period of time, this can lead to a permanent loss of nerve function. 4 For this reason, immediate treatment of shoulder impingement is paramount to restoring function and normal movement.
Why are ligaments important to the scapula?
Ligaments are vital to aid in the maintenance of scapula stability. Injury to the ligaments surrounding the scapula can occur and result in a range of symptoms depending on the severity.
What is the purpose of upward and downward rotation of the scapula?
Upward rotation and downward rotation of the scapula assist with stabilization of the shoulder capsule during excessive arm motion. Upward rotation of the scapula occurs when the arm moves both up and outward simultaneously. This seemingly simple motion requires significant shoulder stabilization due to the intricacies of the humerus and scapula.
What is the body of the scapula?
The body of the scapula consists of a triangular-shaped flat blade, with an apex pointed below. Since it is triangular, it bears three borders.
What is the function of the scapula?
The scapula helps in several daily movements and smooth motion of the upper arm, based on the movements mentioned above.
What joint is between the glenoid fossa and the rounded head of the humerus?
Glenohumeral joint: This is a ball and socket joint formed between the glenoid fossa of the scapula and the rounded head of the humerus.
How many ways does the scapula move?
The movement of this bone is coupled with the humerus, meaning whenever you move your arm, your scapula also moves. It can move in six different ways, towards (retract) and away (protract) from the vertebral column, up and down (elevate and depress), and also rotate upwards and downwards. There are 17 muscles attached to it that help to produce these movements.
Where is the Glenoid Fossa located?
Glenoid fossa – It is a shallow pyriform cavity located at the lateral angle of the scapula. It articulates with the rounded head of the humerus, forming the glenohumeral (shoulder) joint.
What is the infraspinous fossa?
Infraspinous fossa: It is the area below the spine of the scapula. It is convex and much larger than the preceding one. At its upper part, towards the vertebral margin, it shows a shallow concavity. In the center, it is convex, while near the lateral border, it has a deep groove running from the upper toward the lower part.
Which muscle is inserted superiorly along the spine, acromion process, and clavicle?
Trapezius muscle: Gets inserted superiorly along the spine, acromion process, and clavicle. It helps to elevate and rotate the scapula during protraction of the humerus beyond 90 degrees.
What are flat bones?
Flat bones are broad bones that provide protection or muscle attachment. These bones are expanded into broad, flat plates, as in the cranium (skull), hip bone (pelvis), sternum, rib cage, and scapula. The flat bones of the human body are as follows: ● Occipital. ● Parietal.
Why are flat bones important?
Flat bones are important as these not only protect vital organs and tissues, but also provide a large surface area for ligament and tendon attachment. Moreover, the spongy bone tissue that is located between the layers of tough compact bone tissue also contains red bone marrow.
What are the lamellae of a spongy bone?
Between these lamellae lie small chambers (lacunae) that contain osteocytes (mature bone cells) in a concentric arrangement around the osteonic canal. On the other hand, spongy bones are less dense. They consist of trabecula e or bar-shaped bones that are arranged along the lines of stress.
What is compact bone made of?
The compact bone is made up of osteons that are tightly packed. The osteons comprise an osteonic (haversian) canal, which is a central canal that contains a few blood vessels and nerve filaments that are surrounded by concentric rings of matrix called lamellae. Between these lamellae lie small chambers (lacunae) that contain osteocytes (mature bone cells) in a concentric arrangement around the osteonic canal.
What are the flat bones in the human body?
Besides some of the facial bones and cranial bones, bones such as the sternum, ribs, scapula, and the hip bone are classified as flat bones. Bodytomy provides a list of all the flat bones in the human body.
What are the bones of the axial skeleton?
While the axial skeleton consists of the skull, sternum, ribs, and the vertebral column (bones that are along the imaginary longitudinal axis), the appendicular skeleton includes the bones of the arms, legs, shoulder girdle, and the pelvic girdle.
What is the name of the bone that connects the hip to the pelvis?
Os coxæ (Hip bone) The right and left hip bones, sacrum, and the coccyx form the pelvis in the human body. The right and left hip bones meet in the front at pubis symphysis, and connect with the sacrum at the back. Each hip bone consists of 3 sections called ilium, ischium, and pubis.
What is the thick layer of bone surrounding the medullary cavity?
The thick layer of bone surrounding the medullary cavity is composed of --- (compact/spongy) bone tissue.
What is the diaphysis of a bone?
a. diaphysis= 3. the shaft of a long bone. In the mature skeleton, --- (red/yellow) bone marrow fills the medullary cavity of a long bone, and --- (red/yellow) bone marrow is located within the proximal epiphyses of long bones such as the humerus and femur. yellow, red.
What is the definition of an osteoblast?
a. Osteoblast = 1. immature cell that lays new bone
What is the only point of articulation between the pectoral girdle and the axial ske?
True or false. The only point of articulation between the pectoral girdle and the axial skeleton is the sternoclavicular joint.
Where is the marrow located in the skeleton?
In the mature skeleton, --- (red/yellow) bone marrow fills the medullary cavity of a long bone, and --- (red/yellow) bone marrow is located within the proximal epiphyses of long bones such as the humerus and femur.
Which part of the tibia lies to the fibula?
In the anatomic position, the tibia lies (medial/lateral) to the fibula.
Does vitamin D help bone growth?
The vitamin D supplements will help maintain the bone health that there still is. However, the patient also has to help stimulate bone growth or slow down bone loss
Overview
- The bones of your skeleton are classified into several categories, including flat bones. Other bon…
Flat bones are thin and flat. Sometimes they have a slight curve. Flat bones serve as a point of attachment for muscles or protection for your internal organs.
Flat bones of the skull
- The bones of your skull surround and protect your brain and also provide support to your face. …
Frontal bone. This bone forms your forehead and the upper portion of your eye sockets. - Parietal bones. You have two parietal bones on either side of your head. They form the top and s…
Occipital bone. This bone forms the back of your skull. It has an opening near the bottom that allows your spinal cord to meet your brain.
Sternum and ribs
- Your sternum is a T-shaped flat bone that’s located in the middle of your chest. It protects your h…
Your ribs are also flat bones. You have 12 of them on either side of your body. They form a cagelike protective structure around the organs of your upper torso.
Scapula
- Your scapula is a flat bone that’s commonly referred to as your shoulder blade. You have two of …
Your scapula also joins together with your collar bone and humerus bone in your upper arm to make your shoulder joint.
Coxal bone
- Your coxal bone is a large, flat bone that forms your pelvis. It’s actually made up of three bones:
Ilium. This is the widest part, located near the top of your pelvis. - Pubis. This is part that sits farthest back in your pelvis.
Ischium. This forms the bottom of your pelvis.
Overview
The scapula (plural scapulae or scapulas ), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either side of the body being roughly a mirror image of the other. The name derives from the Classical Latin word for trowel or small shovel, which it was tho…
Structure
The scapula is a thick, flat bone lying on the thoracic wall that provides an attachment for three groups of muscles: intrinsic, extrinsic, and stabilizing and rotating muscles. The intrinsic muscles of the scapula include the muscles of the rotator cuff—the subscapularis, teres minor, supraspinatus, and infraspinatus. These muscles attach to the surface of the scapula and are res…
Function
The following muscles attach to the scapula:
Movements of the scapula are brought about by the scapular muscles. The scapula can perform six actions:
• Elevation: upper trapezius and levator scapulae
• Depression: lower trapezius
Clinical significance
Because of its sturdy structure and protected location, fractures of the scapula are uncommon. When they do occur, they are an indication that severe chest trauma has occurred. Scapular fractures involving the neck of the scapula have two patterns. One (rare) type of fracture is through the anatomical neck of the scapula. The other more common type of fracture is through the surgical nec…
Etymology
The name scapula as synonym of shoulder blade is of Latin origin. It is commonly used in medical English and is part of the current official Latin nomenclature, Terminologia Anatomica. Shoulder blade is the colloquial name for this bone.
In other animals
In fish, the scapular blade is a structure attached to the upper surface of the articulation of the pectoral fin, and is accompanied by a similar coracoid plate on the lower surface. Although sturdy in cartilagenous fish, both plates are generally small in most other fish, and may be partially cartilagenous, or consist of multiple bony elements.
See also
• Scapulimancy/Oracle bone
External links
• Anatomy photo:10:st-0301 at the SUNY Downstate Medical Center - "Joints of the Upper Extremity: Scapula"
• shoulder/bones/bones2 at the Dartmouth Medical School's Department of Anatomy
• shoulder/surface/surface2 at the Dartmouth Medical School's Department of Anatomy