Week 9: Musculoskeletal Care - Back and lower limb Flashcards
How many vertebrae can be found in the cervical region?
7
How many vertebrae can be found in the thoracic region?
12
How many vertebrae can be found in the lumbar region?
5
The lumbar vertebrae articulate inferiorly with what bony
structure?
The sacrum which is the posterior aspect of the pelvis.
Think about how the ribs connect the vertebrae to the sternum anteriorly. In what direction do the ribs proceed from a posterior to anterior direction?
Superior to inferior (at a diagonal).
Identify the 5th rib. Where does this rib insert upon anteriorly?
Body of the sternum.
What vertebrae does it articulate with posteriorly (Hint: It
articulates with two!)?
T4 and T5
At the junction of the lamina and the pedicles, what structures project superior and inferior?
Articular processes of the spine
Spinous processes: Posterior and inferior projection of bone, a site of attachment for muscles and ligaments.
3 anatomical features of the coccyx
The coccyx is a small bone, which articulates with the apex of the sacrum. It is recognised by its lack of vertebral arches. Due to the lack of vertebral arches, there is no vertebral canal, and so the coccyx does not transmit the spinal cord
3 anatomical features of the sacrum
The sacrum is a collection of five fused vertebrae. It is described as an upside down triangle, with the apex pointing inferiorly. On the lateral walls of the sacrum are facets, for articulation with the pelvis at the sacro-iliac joints.
3 anatomical features of the sacrum
The sacrum is a collection of five fused vertebrae. It is described as an upside down triangle, with the apex pointing inferiorly. On the lateral walls of the sacrum are facets, for articulation with the pelvis at the sacro-iliac joints.
Why is the 5th rib an important landmark for performing a
thoracostomy?
A Thoracostomy is a small incision into the thorax, usually to drain fluids associated with a pneumothorax. This is an important landmark and in full expiration the diaphragm can reach all the way up to the 5th rib, so going
below this space risks inserting the needle into the abdomen or the diaphragm.
In addition to touching the vertebral bodies posteriorly, each rib proceeds transversely to articulate upon what bony structure of the vertebrae (before swooping anteriorly)?
Transverse process of vertebra
Take note that on the underside of each rib body there is a costal groove. Find this groove. What normally is found in this groove? Where is the general destination of these structures?
Intercostal vein, artery, and nerve
Intercostal muscles, muscles of the thoracic wall, sensory to the abdominal wall via lateral and anterior cutaneous branches
Describe four features of the lumbar vertebrae that make them unique?
Largest bodies.
Thick spinous processes.
No foramina or costal facets on transverse processes.
Vertebral foramina are small and triangular.
Is the lumbar curvature primary or secondary?
How is it formed?
Secondary – formed from walking upright.
There is a bridge of bone that connects the superior and inferior articulating facets of the vertebrae. What is this bridge of bone called?
Pars interarticularis.
If the Scotty dog’s neck gets fractured (through the lamina of each side of the vertebra), which then can cause the vertebral column to slip due
to the forces put on the lumbar spine. What is this fracture with slippage called?
Spondylolisthesis.
An exaggerated thoracic curvature is called..
kyphosis
An exaggerated lumbar curvature is called..
Lordosis
What are the distinguishing characteristics that allow you to tell a female from a male pelvis (List THREE distinguishing features of each)?
Female:
- circular pelvic inlet
- pubic arch angle wider (approx 80 Deg)
- less distinct sacral promontory
- broader alae
Male:
- heart shaped pelvic inlet
- pubic arch angle smaller (50-60 deg)
- ischial spines project more medially into pelvic cavity
What are the distinguishing characteristics that allow you to tell a female from a male pelvis (List THREE distinguishing features of each)?
Female:
- circular pelvic inlet
- pubic arch angle wider (approx 80 Deg)
- less distinct sacral promontory
- broader alae
Male:
- heart shaped pelvic inlet
- pubic arch angle smaller (50-60 deg)
- ischial spines project more medially into pelvic cavity
Where is the Ischial spine of the pelvis?
On the posterior aspect of the ischium there is an indentation known as the greater sciatic notch, with the ischial spine at its most inferior edge.
Anatomically, the perineal body lies just deep to the skin. It functions as a point of attachment for muscle fibres from the pelvic floor and the perineum itself.
List 5 structures that attach to the perineal body.
Levator ani (part of the pelvic floor).
Bulbospongiosus muscle.
Superficial and deep transverse perineal muscles.
External anal sphincter muscle.
External urethral sphincter muscle fibres.
Look at a female pelvis that has the superficial perineal pouch as part of it. What are the four muscles seen from below?
ischiocavernosus
bulbospongiosus
transverse perineal
perineal body
Which two muscles in the MALE, are responsible for helping to maintain erections? By what mechanism does it accomplish this?
A: Ischiocavernosus and B: Bulbospongiosus B helps to compress the bulb of the penis which restricts venous drainage, and A helps to maintain an erection by compressing the deep dorsal vein and slowing venous return.
Underneath the gluteus maximus, Describe and list the muscles you see in the gluteal region at this
depth, including those that act to laterally rotate the hip, and those that act to stabilize the pelvis?
a. Lateral rotators of the hip
i. Piriformis
ii. Gemillis
iii. Obturator externus
iv. Quadratus femoris
Stabilizers: Gluteus medius, gluteus minimis
Underneath the gluteus maximus, what three nerves can you see in this view (with the gluteus maximus removed)?
Sciatic nerve, Superior gluteal nerve, Inferior gluteal nerve.
Which nerve is responsible for innervation to the gluteus
medius and minimis?
Superior gluteal nerve innervates the medius and minimis
What is the innervation and major action of rectus femurs?
femoral nerve
flex hip, extend knee
What is the innervation and major action of semitendinosus?
Sciatic nerve
flex knee
What is the innervation and major action of gluteus Maximus?
Inferior gluteal nerve
extend hip
What is the innervation and major action of adductor longs?
obturator nerve
adduct hip
What is the purpose of the ACL and PCL (Specify what movements they prevent)?
The ACL prevents anterior tibial movement on the femur
The PCL prevents posterior tibial movement on the femur
if an individual were to get kicked to the back of a flexed knee what ligament would they damage?
ACL
The Drawer and Lachman test for anterior cruciate ligament damage. Which test is more sensitive, and why?
Lachmans test is more sensitive because it is done with the knee at a 20 degree flexion, which reduces false negatives associated with hamstring tension that is present with a full 90 degree flexion that the patient has during the Drawer test.
Name the bones that articulate at the hip joint
2 bones, femur and acetabulum
Name the bones that articulate at the knee joint
3 bones, femur, patella, and Tibia
Name the bones that articulate at the ankle joint
3 bones, tibia, fibula and Talus
What is it called when the neck of the femur breaks immediately beneath the head?
subcapital
What is it called when the neck of the femur breaks near its midpoint?
cervical
What is it called when the neck of the femur breaks adjacent to the trochanters?
basal
What is it called when the femur fracture line is between, along or just below the trochanters?
pertrochanteric
Xray image of calcanea fracture?
How do you think that this injury occurred? Where would you also want to look in a patient that presents with this injury?
Likely a high force/energy trauma from somebody falling from height onto their heels. Look at the joint above, and not just one joint above. Check the pelvis, spine,
even skull, as the energy/force can be transmitted all the way up the body.
Think about how the femur sits in the acetabulum. i) If you were to have a posterior dislocation of the hip, what nerve are you worried about injuring? ii) What are three functional issues you might present with on injuring this nerve?
i) Sciatic nerve.
ii) Limb relatively useless, impaired hip extension, very weak knee flexion, absent ankle and digit plantarflexion and dorsiflexion, foot deformity/collapse.
consider a patient who comes into the
Emergency Department after having been hit by the front bumper of a car. i) At what joint would you look first for a fracture? ii) With a proximal fibular fracture what very important nerve wraps around the proximal head/neck of this bone that is in danger of being
damaged? iii) If damaged, what functional losses would the patient have?
i) The knee joint, as that is the level of the car bumper.
ii) The Common Fibular nerve.
iii) Weak dorsiflexion (foot slap when walking), absent dorsiflexion (foot drop), absent ankle eversion (thus they would be prone to inversion injury/sprain/future fractures).
Visualize a tibia and leg model. What do you notice about the tibia in relation to the musculature that surrounds it? How might these features affect the likelihood of fracture?
The bone is very superficial, located in the subcutaneous and is unprotected anteromedially through its course down the leg. It is also particularly slender
in its lower third. This makes the tibia the commonest long bone to be fractured and suffer a compound injury.
Femur fracture not on the neck.
With this fracture are you worried
about necrosis of the femoral head? Why or why not?
Right subtrochanteric femur fracture. The fracture is posteriorly displaced and mildly impacted. The proximal fracture fragment is laterally angulated.
You are not that worried about necrosis immediately as the blood supply to the internal aspects of the joint capsule and femoral head have likely been
preserved. You would be more worried about a femoral neck fracture that is inside the joint capsule as that would cut off all blood supply to the femoral head and cause necrosis.
Your patient has a patella fracture. What tendon and what ligament will no longer be functioning correctly with the fracture seen below?
Patellar ligament & Quadriceps tendon.
How can you tell if the patient is adolescent or adult by looking at a knee X-ray?
you can see the epiphyseal growth lines have not sealed (only has partial fusion).
What is the artery and nerve that supplies the anterior compartment of the leg? Identify TWO muscles found in this compartment?
Anterior tibial artery.
Deep Fibular nerve.
Tibialis anterior – Extensor Hallucis – Extensor digitorum Longus – (Very minor: Fibularis tertius)
Describe the way in which the anterior tibial artery proceeds onto the dorsum of the foot to become another artery. i) Once on the dorsal aspect of the foot the tibial artery turns into what artery?
ii) How can you find the pulse of this artery on the dorsal aspect of the foot (Hint: describe the two tendons it lies between)? iii) Now find this pulse on yourself. Why would you want to be able to find this pulse on a patient?
i) Dorsalis pedis artery.
ii) Between the tendons of extensor halluces longus and extensor digitorum.
iii) To check for peripheral blood flow – to ensure there isn’t a compartment syndrome or a clot after surgery that may be blocking blood flow to the foot.
Identify the tarsal tunnel. This tunnel contains numerous structures. i) Is this tunnel located posterior to the medial or lateral malleolus? ii) Identify on the model, then list below, the structures that are found in this tunnel
from an anterior to posterior position. ii) What important
peripheral pulse can be felt in this tunnel?
i)Medial malleolus.
ii)Tibialis posterior – flexor digitorum – posterior tibial artery – vein – tibial
nerve – flexor hallucis longus.
iii)Posterior tibial artery. This pulse can be felt 1/3rd of the way back along a line passing between the medial malleolus and calcaneus.
What forms the superior border of the femoral triangle?
Inguinal ligament
What forms the medial border of the femoral triangle?
Adductor longus
What forms the lateral border of the femoral triangle?
Sartorius
What four structures can be found in the femoral triangle (name them from a lateral to medial position)?
Name two reasons why this triangle is important clinically
Femoral nerve – femoral artery – femoral vein – lymphatics. Clinically it is an access point for vascular structures, you can palpate here for pulsation, also suspicious lumps of the groin might appear hear along the lymphatic lines
After a “cut down procedure” for insertion of an intravenous line into the great (long) saphenous vein, your patient complained of numbness and loss of sensation on the medial aspect of the foot.
What is the explanation of this occurrence?
The needle probably injured the saphenous nerve whose innervation is of the medial aspect of the foot.
List 4 muscles innervated by the femoral nerve
Hip Flexors
- Pectineus – adducts and flexes the thigh, assists with medial rotation of the thigh.
- Iliacus – acts with psoas major and psoas minor (forming iliopsoas) to flex the thigh at the hip joint and stabilise the hip joint.
- Sartorius – flexes, abducts and laterally rotates the thigh at the hip joint. Flexes the leg at the knee joint.
Knee Extensors
- Quadriceps femoris (rectus femoris, vastus lateralis, vastus intermedius) – extends the leg at the knee joint. Rectus femoris also steadies the hip joint and assists iliopsoas in flexing the thigh.
