Muscles Bones Joints Flashcards
What type of joint is found at the elbow and what movements normally occur at the elbow joint?
Elbow joint is a synovial hinge joint; movements are flexion and extension
What movement(s) of the glenohumeral joint would the superior muscle in diagram A induce if it contracted?
The muscle is coracobrachialis. It lies in front of the glenohumeral joint and so will flex the humerus at the glenohumeral joint. It also lies medial to the glenohumeral joint and will act as an adductor of the joint.
What movement(s) of the elbow joint would the inferior muscle (brachialis) induce if it contracted?
The brachialis crosses in front of the elbow joint and will cause flexion of the joint when it contracts.
What effect on the position of the scapula would contraction of the serratus anterior muscle have?
When the serratus anterior muscle contracts, it will pull the scapula around the thoracic wall so that the glenoid cavity of the glenohumeral joint faces anteriorly.
In which sporting activity would this movement of the scapula occur frequently?
(The large muscle is the serratus anterior muscle. When it contracts, it will pull the scapula around the thoracic wall so that the glenoid cavity of the glenohumeral joint faces anteriorly.)
Boxing – if punching someone in front of you it requires movement of most of the joints in the upper limb. As far as the glenohumeral joint is concerned, as well as movements at the joint, the glenoid cavity (and hence the joint) has to be positioned so that it faces anteriorly. Otherwise when punching, the punch would be directed laterally (and miss anyone standing in front of you!)
Which back muscles do you think are commonly affected in this condition?
A weight lifter was preparing for a competition by lifting increasingly heavy weights. During hyperextension of his vertebral column, he suddenly felt a severe pain in his lower back. Following physical examination, it was decided that he was experiencing acute back pain.
The back muscles that are usually involved are the deep muscles (erector spinae and its subdivisions).
What was the likely cause of the man’s acute back pain?
A weight lifter was preparing for a competition by lifting increasingly heavy weights. During hyperextension of his vertebral column, he suddenly felt a severe pain in his lower back. Following physical examination, it was decided that he was experiencing acute back pain.
Poor posture and improper lifting mechanics cause most acute back pains
What are the main actions of the major back muscles?
Back muscles (erector spinae & others) extend the vertebral column and flex it laterally. Deep back muscles are helpful in the rotation,
- A neurophysician was preparing to perform a lumbar puncture to establish the diagnosis in a patient with suspected intracranial bleeding. In this procedure a needle is inserted into the subarachnoid space around the spinal cord in order to withdraw a sample of cerebrospinal fluid (CSF). Access is gained though the back and in the midline.
At what level(s) would the neurophysician consider inserting the needle?
Lumbar puncture is usually done between L3/L4 or L4/L5 vertebrae.
In Order to withdraw a sample of cerebrospinal fluid (CSF). Access is gained though the back and in the midline…
Why are these vertebral levels used?
b and c) These levels are safe in infants, children and adults because the spinal cord usually ends at L3 vertebra in infants and the inferior end of L1 vertebra in most adults.
CSF Tap
Are these/adult levels safe in infants?
b and c) These levels are safe in infants, children and adults because the spinal cord usually ends at L3 vertebra in infants and the inferior end of L1 vertebra in most adults.
CSF Tap
Normally the patient is asked to lie on their side and in a curled up position. How does this aid the procedure?
d) The patient lying on their side normally provides the most comfortable (and safe) approach for the physician. By bending their spine, the vertebral spines fan out and make it easier to locate the intervertebral space through which the needle must pass to reach the spinal cord area.
- A middle aged man experienced a severe sudden, lower back pain, while lifting a heavy object. The pain radiated down to his thigh, leg and dorsum of his foot. The radiological test (MRI) revealed that he had a protruding intervertebral disc at L5/S1 vertebral level.
What are the two main parts of the intervertebral disc?
Intervertebral discs are present between the bodies of adjacent vertebrae. The inner part is called the nucleus pulposus and consists of a gelatinous mass and the outer part the annulus fibrosus consisting of fibrocartilage.
What is meant by the term disc prolapse?
Disc degeneration is associated with dehydration (loss of water) of the nucleus pulposus which leads to displacement (prolapse) of the disc. This is often onto the posterolateral side of the vertebral column causing compression of emerging spinal nerves.
c) What causes the IV disc to prolapse or herniate?
Lifting heavy weights, ageing and bone diseases
