Locomotor POL

MDSC1105 Musculo-skeletal (Locomotor) System


CASE #1


Groups 9 Physiology Lecture Theatre
Groups 10 PreClinical Lecture Theatre


A young woman travelling as a front seat passenger was involved in a
motor vehicle accident and suffered an injury to her right hip. Movement
at the hip, foot and ankle joints were limited by pain. At the emergency
unit, the attending physician noticed that her right lower limb was held in a
characteristic position suggestive of a posterior hip dislocation and this was
confirmed by Xrays. The emergency orthopaedic surgeon then reduced the
dislocation in O.R. Her recovery was such that she could now fully move the
hip but that after six months, movements to the ankle and foot joints did not
return.


1. Describe the anatomical features that contribute to the stability of the hip
joint.


2. Describe the blood and nerve supply to the hip joint.


3. What are the clinical features of dislocation of the hip joint?


4. Explain the cause for lack of movements in the ankle/foot joints initially
as well as for later on.


MDSC1105 Musculo-skeletal (Locomotor) System


CASE #2


Groups 11, 13
Groups 12, 14


Physiology Lecture Theatre
PreClinical Lecture Theatre


A 24 yr old male was shot from a buckshot rifle in his upper left forearm. The man
presented to the emergency unit about 4 hours later with significant swelling of the arm.
Apart from obvious pain and multiple small entry wounds, the hand was noted to be
pale and there were no radial or ulnar pulses. X Rays showed fracture to the shafts of
the radius and ulna bone. He was immediately prepared for and taken to the operating
theatre where he had fixation of the fractures, followed by direct repair to the brachial
artery which was transected and repair of the median nerve. Following the surgery the
man was noted to have much more swelling of the forearm with decreased pulses 6 hours
after surgery. He was again taken back to theatre for further surgery with a successful
outcome.


1. Explain normal ossification of a long bone, and ossification following a fracture.
(11,12)


2. Describe the histology of a typical neuron and its axon (in a peripheral nerve), and
describe the changes that occur following nerve repair. (13,14)


3. Describe the arterial blood supply of the forearm and hand. (11,12)


4. What are the clinical symptoms and signs of acute arterial insufficiency? (13,14)


5. What is the anatomical basis for survival of the hand in spite of no apparent blood
flow for a prolonged period? (11,12)


6. Why did the man develop more swelling after the surgery with decreased pulses?
(13,14)


7. Explain the anatomical, physiological and biochemical events for this swelling.
(11,12)


8. What are the physiological defences against this event? (13,14)


MDSC1105 Musculo-skeletal (Locomotor) System


Groups 15
Groups 16


CASE #3


Physiology Lecture Theatre
PreClinical Lecture Theatre


A 35yr.old teacher noticed that some 2 years after delivery of her first child that she had
developed varicose veins along the medial side of her leg. Her condition was worsened
by her occupation which involved long standing, so much so that in spite of conservative
medical management she had developed an ulcer over the medial aspect of her ankle and
varicosities over the outer aspect of the ankle and foot. She initially was treated by having
the veins injected and had good cosmetic outcome. However she developed gradual
return of the varicosities along the inner aspect of the leg. She returned to her surgeon
who then offered a surgical approach to the management of her problem


1. Describe the anatomy of the superficial venous and deep systems of the leg and
thigh and the histology of these veins


2. Explain the disordered physiology and pathogenesis of the ulcer.


3. Explain anatomically why she developed varicosities on the medial aspect of leg.


4. Discuss the factors involved in venous return from the lower limb


5. Explain anatomically why varicosities frequently develop after pregnancy.