Full Osteology video
There are 8 bones which form the carpus and they arranged in two rows of bones. We have the proximal row and a distal row. The proximal row consists of the following bones – you have scaphoid, the lunate, the triquetrum and the pisiform. The distal row of bones consists of the following. You have the trapezium, trapezoid, capitate and hamate.
The scaphoid is the most lateral of the bones of the proximal row. It is the largest. It has a rounded tubercle which is called the tubercle of the scaphoid. The lunate is next to scaphoid from lateral to medial. And it is semilunar in shape. The triquetrum is sandwiched between the lunate and the pisiform. The pisiform looks like a pea. It is a big sesamoid bone. It is the most medial of proximal row of carpal bones. The trapezium is the most lateral of the distal row of carpal bones. It has a tubercle at its ventral aspect and a grove. The trapezoid is the next bone to the trapezium. The capitate is the most central of all carpal bones and it is the largest. It articulates with metacarpal III. Hamate is cuneiform in shape. It is provided with a hook of hamate by which it articulates with metacarpal V through ligaments.
The clavicle is the collar bone and it is part of the pectoral girdle and assists in swinging the upper limb away from the trunk. This is a major adaptation of primates which climb trees in brachiation. The clavicle is placed directly below the skin of the shoulder region. It is divided into a lateral 1/3, and a medial 2/3. The lateral 1/3 is flat while the medial 2/3 is cylindrical.
It has two ends by which it articulates with different bones- a sternal end with a sternal facet by which it articulates with the sternum and a clavicular end by which it articulates with the clavicle. The clavicle has two borders at its lateral flattened part- they are the anterior border and the posterior border. It also has two surfaces at its flattened part. A superior surface and an inferior surface which carries the subclavian groove.
The clavicle has the following borders. At its lateral 1/3 it as has an anterior border which carries the deltoid tubercle for attachment of the deltoid muscle and a posterior border. It also has two surfaces – a superior surface and an inferior surface. The inferior surface carries the trapezoid line for the attachment of the trapezoid ligament and a conoid tubercle for the attachment of the conoid ligament . It also has a subclavian groove by which it is attached to the subclavius muscle.
The head of femur is cylindrical and it has a pit which is called the fovea capitis by which the ligamentum teres or the round ligament of the head of the femur is attached to the head. This ligament carries blood from the acetabulum to the head of the femur. The head is smooth. The neck is also cylindrical and long. The femur has the longest neck of all the long bones and its a true surgical neck unlike the humerus that has a distinct anatomical neck which is its growing neck as opposed to the the weakest point between the head and the shaft. This is easily liable to fracture. The neck is placed at an angle of 125o to the shaft and ends at its junction with the trochanters. The greater trochanter and lesser trochanter are both interconnected by intertrochanteric crest posteriorly and an intertrochanteric line anteriorly. The intertrochanteric fossa is placed just inferior to the greater trochanter. The shaft of the femur begins at the trochanters. It is long and cylindrical. It joins the neck at the trochanters -greater and lesser trochanters. These trochanters are joined in front by intertrochanteric line and behind by the intertrochanteric crest. The crest has a quadrate tubercle at its middle. The shaft carries some important land marks at its back. They are, the linea aspera. The linea aspera runs from its junction with the spiral line medially and the gluteal tuberosity laterally. It then runs to the supracondylar lines inferiorly. You have the medial and the lateral supracondylar lines. The distal extremity of the femur carries the condyles and their intercondylar area. The lateral condyle is more massive and bigger than the medial one. It carries the lateral epicondyle. The medial condyle is smaller and it has the adductor tubercle for the attachment of the adductor magnus.
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