Anatomy Flashcards
List three gross anatomical features/structures that prevent hip dislocation (promote
stability of the hip joint) in a normal adult hip, and briefly explain the role of each
feature/structure.
Shape of bones – ball (head of femur) and shallow socket (acetabular cavity). Acetabular
labrum (a rim of fibrocartilage attached to the margins of the acetabulum) helps to deepen the
joint cavity (2)
Fibrous capsule that surrounds the joint - attaching proximally to the acetabulum and distally
to the intertrochanteric line and to the neck of the femur – encloses the joint cavity. (2).
Ligaments – iliofemoral, ischiofemoral and pubofemoral ligaments, which are also
thickenings of the joint capsule; transverse ligament of the acetabulum bridges the acetabular
notch (2)
Muscles/ tendons
Complete the table below with respect to four ligaments that maintain the stability of
the vertebral column (back).
Anterior longitudinal - found on the anterior part of vertebrae
Posterior longitudunal- found on the posterior part of vertebrae
Interspinous- found between the spinous process (inter- between spinous)
Supraspinous- This are found on the tips of the spinous process.
Ligamentum nuchae- found between the occipital bone and the cervical vertebrae
Ligamentum flavum- found between laminae
. Explain which meniscus is more likely to be torn in a knee injury such as Mr Modise’s.
(2 marks)
Medial – as the medial/ tibial collateral ligament attaches to the medial meniscus and
the lateral collateral ligament does not attach to the lateral meniscus.
Explain the function and contribution to the stability of the knee joint of two of the
ligaments that are observed when the knee joint is opened.
ANTERIOR CRUCIATE LIGAMENT (ACL) During extension of the knee the ACL is
taut, preventing anterior displacement of the tibia in relation to the femur (or posterior
displacement of the femur in relation to the tibia) and hyperextension of the knee. The
ACL is lax when the knee is flexed. During extension of the knee when the ACL is most
taut, it can be torn. Holds bones together.
POSTERIOR CRUCIATE LIGAMENTS (PCL) The PCL is taut during flexion of the
knee, preventing posterior displacement of the tibia in relation to the femur and
hyperflexion of the knee. When walking downhill or up stairs, the PCL helps to stabilize
the weight-bearing flexed knee. Holds bones together.
SCENARIO 2 [102.5 marks]
Mrs. Rose Williams is 73 years old and lives on her own on the third floor in a block of flats. Her
husband died 10 years ago and left her with a small pension. Her diet consists mostly of tea and toast.
Mrs. Williams fell one morning in her flat and was taken to hospital. The casualty officer noted she had a
painful right hip and pain in the lower back. The doctor ordered x-rays of the hips and lower back which
revealed a fracture of the neck of the right femur but no other bony injury. Later that day an orthopaedic
surgeon replaced the head of her femur with an artificial one. When Mrs. Williams awoke from the
anaesthetic she complained of pain in the operation site and was given an intramuscular injection to ease
it.
- Based on the case scenario, suggest two possible explanations of why Mrs Williams’ hip fractured.
(2 marks) - After the operation Mrs. Williams was given an injection in the left buttock.
(a) Name the major nerve that is most at risk of being damaged by a negligently administered
intramuscular injection in this region. State the nerve root origins of this nerve. (1 mark)
(b) Describe one sensory and one motor consequence of damage to this nerve if the whole nerve was
damaged. - If Mrs Williams had been given an intramuscular injection in the upper arm, name the major nerve
that is potentially at risk of damage from a badly administered injection given too far posteriorly
in this region. (It is also at risk in a fracture of the humerus). (1mark) - Briefly describe where the nerve referred to in the previous question runs in the arm. (1 mark)
- Briefly describe two motor consequences of injury to the nerve referred to in Q.18 assuming the
whole nerve was damaged. (2 marks) - Mrs Williams’ back pain was thought to be caused by muscular strain from the fall. Briefly describe
the arrangement of the erector spinae group of muscles including their nerve supply and actions.
. (6 marks)
She may have tripped and fallen on her hip causing it to fracture.(1)
She may be so osteoporotic that her hip fractured spontaneously and she fell as a result.(1)
Sciatic nerve. L45S123 (1)
Any movement or sensory deficit relevant to sciatic nerve or its branches.
Radial nerve
Posteriorly around shaft of humerus
Any two movements e.g. extension of elbow, wrist, fingers and relevant muscles.
Iliocostalis, longissimus, spinalis – arrangement (3)
Extend head and vertebral column, maintain posture, paradoxical action to control flexion
NS dorsal rami spinal nerves
CASE SCENARIO 2 [32 MARKS]
Mr Mxolisi Mda is a 55 year old man who was travelling back to his work as miner from his home town
after the Christmas holidays when the bus in which he was travelling veered off the road into a ditch. Mr
Mda was thrown from the bus. When the accident rescue team arrived they found him lying on the
ground, conscious and with pain in his back. He had difficulty moving his legs. The paramedics were
concerned that he could have developed paraplegia and he was transported to hospital by helicopter.
List the nerve root origins of the sciatic nerve.
- If Mr Mda’s sciatic nerve had been damaged, list the muscles in the thigh that would be affected.
- State, in summary form, the functions of the sciatic nerve and its branches supplying the lower
limb below the knee. - If Mr Mda was found to have numbness (no feeling) in his legs and abdomen up to the level of his
umbilicus, state at what nerve root level his spinal cord is likely to be injured. (1 mark) - On hitting the ground, Mr Mda’s spine was subject to considerable extension stress. Name the
most important ligament in the spine that is responsible for limiting extension of the spine.
(1 mark)
L4,5,S1,2,3
Semitendinosus, semimembranosus, biceps femoris, adductor magnus (1 mark for hamstrings)
All myocutaneous supply except the medial cutaneous side (supplied by saphenous nerve from
femoral nerve)
T10
Anterior longitudinal ligament
Briefly describe the bony surfaces and ligaments of the ankle joint and how these features
contribute towards ankle stability.
3 bony surfaces of three bones (tibia, fibula, talus), mortice; upper surface of talus more stable in
dorsiflexion; two ligaments medial and lateral collateral, 6 marks
- State precisely where the fracture has occurred in Mrs Chimombo, as shown in Figure
1 in the case. (0,5 mark)
Neck of the femur (1/2) - Briefly describe the ligaments situated anteriorly in the hip joint.
Iliofemoral - inverted Y shape (1)
and pubo femoral from pubic ramus to lower femoral neck, deep to iliofemoral (1)
- Mrs Chimombo underwent hip surgery and subsequent rehabilitation by a
physiotherapist.
a. Briefly describe the attachments and nerve supply of the two main muscles that
the physiotherapist would treat in order to regain abduction of the hip
Briefly explain how these muscles enable a healthy person to stand on one leg
without falling over.
Gluteus medius and minimus (1). ½ for each origin (1) ; ½ for each insertion (1); ½ for each
nerve supply = superior gluteal nerve for both (1
The abductors of the leg that is on the ground (1/2) tilt the pelvis to that side (1/2) so that the
centre of gravity falls through the leg that is the one the ground (1/2) enabling full weight
bearing on that leg (1/2)
While Mrs Chimombo was falling, she extended her back and arms in an effort to
break her fall.
a. Name one ligament in the spine that would limit overextension of her spine.
(1/2 mark)
Anterior longitudinal ligament
- Briefly describe three functions in the hand whereby the doctor could assess the
function of the median nerve in Mrs Chimombo. (3 marks)
Full marks given to these options as they are only supplied by median nerve.
Oppose thumb, flex thumb, flex fingers, flex MPJ while extending IPJ digits 2 & 3, median
nerve sensory distribution of palm and lateral 3 ½ digits, flex DIPJ of fingers 2+3,
Half marks given to these as the median nerve causes the action but is not the only nerve
innervating muscles that perform the action
Abduction of thumb (also radial n branch because of Abd poll longus)
Radial deviation of wrist is caused by extensor carpi radialis brevis and longus innervated by
radial nerve
Flexion of wrist – also caused by flexor carpi ulnaris innervated by ulnar nerve.
