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.
List 4 muscles innervated by the obturator nerve
The obturator nerve innervates all the muscles in the medial compartment of the thigh except the hamstring part of the adductor magnus, which is innervated by the tibial nerve.
Adductor Longus – adducts thigh
Adductor Brevis – adducts thigh
Adductor Magnus – adductor part adducts and flexes thigh, hamstring part extends thigh
Gracilis – adducts thigh
Obturator Externus – laterally rotates thigh
Name the nerve.
This nerve can be damaged during surgery involving the pelvis or abdomen. Symptoms include numbness and paraesthesia on the medial aspect of the thigh and weakness in adduction of the thigh. Alternatively, the patient could present with posture and gait problems due to the loss of adduction.
Obturator nerve.
Sensory function of obturator nerve
The cutaneous branch of the obturator nerve supplies the skin of the middle part of the medial thigh.
Motor function of sciatic nerve
Motor: Innervates the muscles of the posterior thigh and the hamstring portion of the adductor magnus. Indirectly innervates (via its terminal branches) the muscles of the leg and foot.
Sensory function of sciatic nerve
Sensory: No direct sensory functions. Indirectly innervates (via its terminal branches) the skin of the lateral leg, heel, and both the dorsal and plantar surfaces of the foot.
True or false?
the sciatic nerve passes through the gluteal region, but it does not innervate any muscles there.
True
The sciatic nerve also indirectly innervates several other muscles, via its two terminal branches. Name them.
Tibial nerve – the muscles of the posterior leg (calf muscles), and some of the intrinsic muscles of the foot.
Common fibular nerve – the muscles of the anterior leg, lateral leg, and the remaining intrinsic foot muscles.
In total, the sciatic nerve innervates the muscles of the posterior thigh, entire leg and entire foot.
The sciatic nerve does not have any direct cutaneous functions. It does provide indirect sensory innervation via its terminal branches. Name them.
Tibial nerve – Innervates the posterolateral and anterolateral sides of the leg, and the plantar surface of the foot (the sole).
Common fibular nerve – Innervates the lateral leg and the dorsal surface of the foot.
Motor function of tibial nerve
Motor: Innervates the posterior compartment of the leg
Sensory function of tibial nerve
Sensory: Innervates the skin of the posterolateral side of the leg, lateral side of the foot, and the sole of the foot.
The tibial nerve innervates all the muscles in the posterior compartment of the leg. They are divided into a deep and superficial compartment. List 4 deep muscles and their function.
Popliteus – Laterally rotates the femur on the tibia to unlock the knee.
Flexor Hallucis Longus – Flexes the big toe and plantar flexes the ankle.
Flexor digitorum Longus – Flexes the other digits and plantar flexes the ankle.
Tibialis Posterior – Inverts the foot and plantar flexes the ankle.
The tibial nerve innervates all the muscles in the posterior compartment of the leg. They are divided into a deep and superficial compartment. List 3 superficial muscles and their function.
Plantaris – Plantar flexes the ankle.
Soleus – Plantar flexes the ankle.
Gastrocnemius – Plantar flexes the ankle and flexes the knee.
Motor function of common fibular nerve
Motor: Innervates the short head of the biceps femoris directly. Also supplies (via branches) the muscles in the lateral and anterior compartments of the leg.
Sensory function of common fibular nerve
Sensory: Innervates the skin over the upper lateral and lower posterolateral leg. Also supplies (via branches) cutaneous innervation to the skin of the anterolateral leg, and the dorsum of the foot.
Which nerve is most commonly damaged by a fracture of the fibula, or the use of a tight plaster cast.
The common fibular nerve
The anatomical course of the common fibular nerve causes it to wrap round the neck of the fibular, and so any fractures of the fibular neck can cause nerve palsy.
Your patient has had a leg cast applied too tightly. You are concerned they will lose the ability to dorsiflex the foot at the ankle joint. What nerve may have been damaged?
common fibular nerve
With the ability to dorsiflex, the foot will appear permanently plantarflexed – known as footdrop. They may also present with a characteristic gait, as a result of the footdrop
Motor function of superficial fibular nerve
Motor: Innervates the muscles in the lateral compartment of the leg.
sensory function of superficial fibular nerve
Sensory: Supplies the vast majority of the skin over the dorsum of the foot, apart from the webbing between the hallux and the second digit. It also supplies the anterior and lateral aspect of the inferior third of the leg.
List two muscles innervated by the superficial fibular nerve
The superficial fibular nerve supplies the fibularis longus and the fibularis brevis. These muscles form the lateral compartment of the lower leg.
Motor function of deep fibular nerve
Motor function: Innervates the muscles in the anterior compartment of the leg, as well as some of the intrinsic muscles of the foot.
sensory function of deep fibular nerve
Sensory function: Supplies the triangular region of skin between the 1st and 2nd toes
During an outbreak of meningitis at a university, a 20-year-old student presents to the Emergency Department complaining of a headache, fever, chills, and stiff neck. On examination, you determine she will need a lumbar
puncture.
What fluid are you withdrawing from the patient during a lumbar puncture?
CSF (Cerebral spinal fluid).
During a lumbar puncture the fluid withdrawn is normally taken from what space in the spinal meninges?
Subarachnoid space.
The pia mater is a highly vascular layer that closely invests the spinal cord and nerves. The pia surrounds the termination of the spinal cord (the conus medullaris) and continues as what structure into the coccyx?
Filum terminale.
What nerve supplies the spinal meninges?
recurrent meningeal nerves
You consider the multiple layers through which your needle would need to pass in order to perform a spinal tap. What specific 10 layers/structures does the needle have to pass through in order to reach the fluid?
1 Skin 2 Superficial Fascia 3 Thoracolumbar Fascia 4 Supraspinous ligament 5 Interspinous ligament 6 Ligamentum flavum 7 Epidural space 8 Dura 9 Arachnoid 10 Subarachnoid space
At which vertebral level would the lumbar puncture be performed? Why?
A lumbar puncture is preferably performed between the spinous processes at the LIV/LV level. It can be performed at a superior level if there is degeneration or fusion of the LIV/LV articulation. By entering at the LIV/LV
level, the needle will penetrate the dural sac inferior to the lower end of the spinal cord (conus medullaris), which typically ends at the level of LI/LII though it may end superiorly at TXII or extend inferiorly to LII/LIII. The spinal
cord usually ends somewhat more inferiorly in children than in adults.
What anatomical surface landmarks of the lower back would you use to find the vertebral level the lumbar puncture is performed at?
Use the most superior points of the iliac crests, connect them by an imaginary line across the patient’s back. This imaginary line passes over vertebra LIV, where you will perform the puncture.
During an outbreak of meningitis at a university, a 20-year-old student presents to the Emergency Department complaining of a headache, fever, chills, and stiff neck. On examination, you determine she will need a lumbar
puncture.
Why was the patient’s neck stiff even though she had no history of cervical spine disease?
Meningitis is inflammation of the lining around the brain and spinal cord – the meninges. When this infected and inflamed lining gets stretched, via neck movements, it causes severe pain.
You consider the anatomy of the cervical spine. List THREE defining characteristics that are unique to the cervical vertebra?
Transverse foramina in the transverse processes
Smaller vertebral body
Larger vertebral foramen
Short bifid spinous processes
C1 and C2 are uniquely named and shaped (Atlas and Atlas)
List three structures found in the vertebral arch
transverse proccesses lamina spinous processes articular procces pedicles
A 49-year-old man with back pain presents to his GP with a possible herniated disc. His MRI scan reveals that there is indeed a protrusion.
In what anatomical direction does a herniated disc usually protrude, and why is this the case?
Disc typically herniates posterolaterally. This is due to the fact that the annulus fibrosus is not reinforced by the posterior longitudinal ligament here
and is weaker in this direction.
A 49-year-old man with back pain presents to his GP with a possible herniated disc. His MRI scan reveals that there is indeed a protrusion.
If the scan reveals that the protrusion is between the L4 and L5 vertebrae, what nerve roots would likely be affected and why?
5th Lumbar Nerve – even though spinal nerves inferior to the cervical region exit BELOW their corresponding vertebrae.
It would rarely affect the 4th lumbar nerve root because of a progressive descending oblique trajectory of the spinal nerve roots. The 4th nerve does exit out of the L4/L5 space, but does so very superiorly, so a bulging disc would affect the L5 nerve as it is still very centrally situated in the vertebral canal.
How do nerve roots exit in relation to vertebral bodies
The 4th nerve does exit out of the L4/L5 space, but does so very superiorly, so a bulging disc would affect the L5 nerve as it is still very centrally situated in the vertebral
canal.
When the internal vertebral venous plexus is ruptured, venous blood may spread into which tissue and space?
Epidural fat is shown in the MRI, the internal vertebral venous plexus lies in the epidural space, thus venous blood from plexus may spread into the fat.
What structure is a collection of dorsal and ventral roots in the spinal canal?
Cauda equine is formed by a great lash of the dorsal and ventral roots of the lumbar and sacral nerves.
What is the name of the conical end of the spinal cord at L1/L2?
Conus medullaris is a conical end of the spinal cord at L1/L2.
Which structure may herniate through the annulus fibrosus, thereby impinging on the roots of the spinal nerve?
IV disc, inner nucleus pulposus may herniate through the annulus fibrosus thereby impinging roots of the spinal nerves.
CSF is produced by the vascular choroid plexuses in the ventricles of the brain and accumulates in which space?
CSF is found in the lumbar cistern, which is a subarachnoid space in the lumbar area.
A 28-year-old woman, seven months pregnant, comes to you complaining of lower back pain, and says that she even feels the pain in her buttocks which
radiates down the posterolateral aspect of her leg.
What nerve do you think is being compressed?
What spinal cord levels does this nerve contain?
Sciatic Nerve.
L4, 5, S1, S2, S3
What are the two terminal branches the sciatic nerve divides into?
And where does this division occur in the lower limb?
Tibial nerve and Common Fibular nerves.
This usually happens anywhere from the mid-thigh to the area proximal to
the popliteal region. However the nerve may separate from each other
much higher up in the lower limb.
Besides pregnancy, identify two other common ways in which sciatic nerve might be injured?
Penetrating traumatic injury.
Posterior dislocation of the hip (sometimes associated with fracture of the posterior lip of the acetabulum to which this nerve is close to).
What bony landmarks of the pelvis and lower limb are used to determine the course of the sciatic nerve? Hence, which injury to the hip joint may damage this nerve?
the posterior superior iliac spine and the ischial tuberosity. It then descends into the thigh vertically at the midpoint between the ischial tuberosity and
the greater trochanter. Hence, posterior dislocation of the femoral head from the acetabulum would stretch or severely damage the sciatic nerve (e.g. consider dashboard impact of front seat occupants in RTA).
An 87-year-old woman presents to you with hip pain after a fall. Xray shows fracture just distal to the femoral head, inside the joint space, proximal to the trochantors. What is this called?
Subcaptial fracture (intracapsular fracture)
An 87-year-old woman presents to you with hip pain after a fall. Xray shows a Subcaptial fracture (intracapsular fracture).
Why is this particular fracture very serious and in need of immediate attention? (When compared to a fracture that is more distal to the femoral head or outside the joint capsule).
With this type of fracture, you have to worry about necrosis of the femoral head due to disruption of the blood supply to it. This type of fracture cuts off
most of the retinacular supply to the head of the femur, as the blood supply to the hip comes from a distal (outside the joint capsule) direction, turning
back in and up on itself in the capsule. Also, remember that the ligamentum teres is a negligible blood supply in the adult and cannot support the femoral head.
The hip joint has a number of ligaments surrounding it that help to hold the femoral head in the acetabulum. What are the three major ligaments of the hip joint capsule? Describe the function of each ligament?
Pubofemoral – prevents excessive abduction of hip.
Ischiofemoal – prevents hyperextension of hip (particularly during standing).
Iliofemoral – prevents hyperextension of hip.
Which of the three major ligaments of the hip joint capsule is the strongest?
Iliofemoral is strongest.
Pubofemoral – prevents excessive abduction of hip.
Ischiofemoal – prevents hyperextension of hip (particularly during standing).
Iliofemoral – prevents hyperextension of hip.
In addition to the major ligaments that make up the hip joint capsule, describe two other anatomical features of the hip joint that help increase its stability?
Acetabular labrum – firocartilage rim that surrounds acetabulum, making the socket deeper; the bony shape of the femoral head and acetabular socket has more bony contact area (when compare with the shoulder); ligamentus teres of the hip; muscles of the hip surround it and help to stabilize it.
The hip is limited to only about 15 degrees of extension. Why is this?
Because of the anteriorly placed strong iliofemoral ligament which prevents hyperextension, ligament becomes very taut in extension of the hip.
An 87-year-old woman presents to you with hip pain after a fall. Xray shows neck of femur fracture.
Why on examination would this patient present with a limb that was shortened and laterally (externally rotated)?
The distal portions of the femur are pulled upwards due to the powerful flexors, extensors and adductor muscles still working on the distal fragment - - pulling. As for the lateral (external) rotation of the foot: The fractured neck
of the femur allows the shaft of the femur to move independently of the hip joint; axis of rotation of the femur normally passing through the head shifts
to pass through the greater trochanter and along the long axis of the femoral shaft. Iliopsoas muscle which in normal situation also acts as a medial rotator, now acts as a lateral rotator of the femur because of the fractured neck.
A 44-year-old man comes to you complaining of a lump in his popliteal fossa, and you decide to complete a differential diagnosis to try to figure out what the lump is.
You start with the skin and soft tissues. If the lump were found here what might you consider it to be?
Lipoma
Sarcoma
Sebaceous cyst
Aneurysm
A 44-year-old man comes to you complaining of a lump in his popliteal fossa, and you decide to complete a differential diagnosis to try to figure out what the lump is.
As you palpate you can feel the borders of the popliteal fossa. Describe what four muscles make up the:
i) Superolateral border;
ii) Supero-medial border
iii) Inferomedial border
iv) Inferolateral border?
i) Biceps tendon.
ii) Semimembranosus with a bit of semitendinosus.
iii) Medial head of Gastrocnemius.
iv) Lateral head of Gastrocnemius.
A 44-year-old man comes to you complaining of a lump in his popliteal fossa, and you decide to complete a differential diagnosis to try to figure out what the lump is.
You suspect your patient might have an aneurysm in the popliteal fossa. What artery would this aneurysm be related to?
Popliteal artery
A 44-year-old man comes to you complaining of a lump in his popliteal fossa, and you decide to complete a differential diagnosis to try to figure out what the lump is.
You suspect your patient might have an aneurysm in the popliteal fossa. As you continue your examination, you are less convinced that it is an aneurysm (because it is not pulsating) and begin to consider the knee
joint and its internal structures. What type of joint is the knee joint?
Modified synovial Hinge joint.
The knee has three bony anatomical articulations. What are these?
Two articulations (Medial and lateral condyles) between the femur and the tibia. One between the patella and the femur.
You want to test the strength of your patient’s ACL. What two tests can be used to do this and how are they different?
Drawer Test – done at 90 degrees flexion of the leg.
Lachmans Test – done at 20 degrees flexion of the leg
What are the two ligaments of the knee that resist valgus and varus forces (specify which does which)?
Medial (tibial) collateral ligament – resists Valgus forces.
Lateral (fibular) collateral ligament – resists Varus forces.
In terms of abduction and adduction movement of the tibia, describe what valgus and varus movements at the knee would mean?
Valgus: Tibial abduction
Varus: Tibial adduction
You notice that your patient has trouble with full extension and full flexion, explain the significance of the process of “locking and unlocking” the knee?
When the knee is fully extended with the leg and foot on the ground, the knee “locks” because of medial rotation of the femur on the tibia. This movement enables the lower limb to become a solid column to support the
weight of the body. In the locked position, the thigh and leg muscles relax without making the knee joint unstable. In order to flex the knee, the knee has to “unlock”; this is done by contracting the popliteus muscle that then results in rotating the femur laterally on the tibia so that flexion of the knee can take place.
A 2-year-old presents with severe pain in her leg after having jumped off her bed. Xray shows a proximal fracture of the femoral shaft.
Overall, how would the leg appear in this girl – shorter, longer?
misalignment of two fractured ends (overriding of the bone ends is produced – due to muscle spasms)
Shorter due to the powerful pull of the adductors, flexors and extensors still pulling on the femur and distal knee.
A 2-year-old presents with severe pain in her leg after having jumped off her bed. Xray shows a proximal fracture of the femoral shaft.
Why would a fracture to the distal femoral shaft, just proximal to the popliteal fossa, potentially be more dangerous?
The femoral artery, and subsequent popliteal artery lie very close to and directly behind this portion of bone, and thus a fracture can lacerate the vessels and cause massive hemorrhage.
A 2-year-old presents with severe pain in her leg after having jumped off her bed. Xray shows a femoral shaft fracture.
Identify the actions the following muscles would have on the proximal segment of the fractured bone?
i) Gluteus Medius and Gluteus Minimus
ii) Iliacus and Psoas Major:
i) Abduction.
ii) Flexion.
A 2-year-old presents with severe pain in her leg after having jumped off her bed. Xray shows a femoral shaft fracture.
You are concerned that the fracture may have disrupted the blood supply to the thigh, leg,and foot. For sake of completeness, you check for the femoral pulse just inferior to the inguinal ligament. In what triangle are you palpating this pulse? What other three structures can be found here?
Femoral Triangle.
Femoral nerve, femoral vein, Lymphatics.
Describe the arterial tree of the lower limb.
bifurcation of deep femoral and femoral.
femoral continues becomes popliteal.
popliteal becomes anterior and posterior tibial arteries.
posterior tibial artery gives off fibular artery.
anterior and posterior tibial arteries anastomose in the foot.
anterior tibial gives rise to dorsals pedis artery.
Describe the anatomical structures you would use to locate and feel the dorsalis pedis artery on the dorsum of the foot?
Located between extensor halluces longus and extensor digitorum, distal to the ankle joint. The artery travels towards the 1st web space of the toes
A 33-year-old basketball player comes to the emergency department after having jumped up to get a rebound. When his foot came down to the floor, he landed on his toes and then rolled his ankle in.
Standing on your tiptoes has a specific terminology used to describe it. What is this term called, and why is it riskier to land in a position where you are on your tiptoes?
Plantar flexion. The ankle is least stable during plantar flexion.
Identify the three bones that articulate to make the ankle joint?
Tibia, Fibula and Talus.
Inversion and eversion movements of the ankle take place at what set of joints?
Subtalar joints.
Name two muscles that invert the foot, and name three muscles that evert the foot?
Invert: Tibialis anterior and posterior.
Evert: Fibularis longus, brevis, and tertius
A 33-year-old basketball player comes to the emergency department after having jumped up to get a rebound. When his foot came down to the floor,
he landed on his toes and then rolled his ankle in.
Given that your patient has severely inverted his ankle, what set of ankle ligaments has he likely damaged (lateral collateral or medial collateral ligaments)?
Lateral collateral ligaments.
A 33-year-old basketball player comes to the emergency department after having jumped up to get a rebound. When his foot came down to the floor,
he landed on his toes and then rolled his ankle in.
Of the ligaments that were likely damaged, one of them is most commonly injured by excessive inversion, what is it called? What clinical test can be used to examine this ligament for a tear?
Anterior talofibular ligament.
Anterior drawer test.
A 33-year-old basketball player comes to the emergency department after having jumped up to get a rebound. When his foot came down to the floor,
he landed on his toes and then rolled his ankle in.
When you proceed to examine the ankle, describe how a malleolar fracture might present in your patient?
Pain, swelling in the area, inability to weight-bear, pain on direct palpation
A 33-year-old basketball player comes to the emergency department after having jumped up to get a rebound. When his foot came down to the floor, he landed on his toes and then rolled his ankle in.
Besides the risk of injury to the malleolus with an excessive inversion of the ankle, what other important bony structure of the foot is prone to an avulsion fracture following forced/excessive ankle inversion?
What muscle inserts upon the bony structure
you identified? (Hint: It is a muscle that when excessively stretched the tendon can avulse the bone off the foot).
Tuberosity of the 5th metatarsal.
Fibularis brevis.
A 56-year-old male patient is recovering from a recent surgical embolectomy of the femoral artery. He is complaining of increasing pain in his leg. You
suspect he may be developing an acute compartment syndrome.
What is a compartment? Which compartments are present in the lower limbs?
Compartment = fascial-bound space that is sealed off from other areas. In the limbs, most compartments are formed by the deep fascia of the limbs and the intervening intermuscular septa.
Lower limbs: Anterior, medial, posterior compartments in the thigh; Anterior, Posterior, Lateral compartments of the leg.
A 56-year-old male patient is recovering from a recent surgical embolectomy of the femoral artery. He is complaining of increasing pain in his leg. You
suspect he may be developing an acute compartment syndrome.
What is an acute compartment syndrome?
A sudden increase in interstitial pressure within a compartment resulting in compromised functioning of the vascular system. Further increases in pressure result in loss of neural and muscular function.
A 56-year-old male patient is recovering from a recent surgical embolectomy of the femoral artery. He is complaining of increasing pain in his leg. You suspect he may be developing an acute compartment syndrome.
How is it diagnosed?
Measure intracompartment pressure in mmHG. Pressure of 30mmHG or more in the compartment indicates a need for surgical treatment. Some use other cut off points.
Some use the Whiteside theory which states that that (Diastolic BP Compartment pressure) should normally be>30. It will also be accompanied by pain (often severe and progressive), pallor, pulselessness (distal to
compartment), paraesthesia, paralysis – although this may not be diagnostic
What are the common causes of compartment syndrome in the arm and in the leg?
Trauma/compression with injury to soft tissues and blood vessels; Infection; inflammation; Fracture & bleed.
Apart from pain what are the symptoms and signs of compartment syndrome?
PAIN, Pallor of affected limb distal to injury, pulselessness (distal to compartment), paraesthesia, paralysis, cold limb.
What are the possible complications of a compartment syndrome if left untreated?
Tissue necrosis due to poor perfusion; reperfusion injury; hypovolaemia; shock; renal failure due to myoglobin release following rhabdomyolysis; metabolic acidosis
What is the initial and definitive treatment of compartment syndrome?
Initial is to monitor intra-compartment pressure, also monitor patient symptoms and vital signs. If pressure reaches cut off (30mmHg) then perform fasciotomy of the compartment.
A 92-year-old man presents to you complaining of hip pain, especially on lateral hip rotation. You suspect he has osteoarthritis.
What three pelvic bones eventually fuse at the acetabulum in the young adult to help form the bony pelvis?
Ilium, Pubic, and Ischium bones.
Identify the 4 major lateral rotators of the hip?
Piriformis.
Gemelli muscles (superior and inferior).
Quadratus femoris.
Obturator internus.
The hip joint and the shoulder joint are both ball and socket joints. Describe how they differ in terms of their function, mobility, stability, and how osteoarthritis might affect your patient?
The hip joint is designed for weight bearing, has less joint mobility, and much more stability when compared to the shoulder. The shoulder is meant to be highly mobile, but as such is very unstable, and is not meant for weight
bearing but is meant to move. OA of the should could lead to painful arc syndrome, or difficulty in anything requires wide ranging arm movements like putting a shirt on over one’s head. As for the hip, OA here would likely
make walking more painful, and any type of lower limb movement have less of a range.
Osteoarthritis (OA) is not primarily an inflammatory process. What normally causes OA?
Abnormal mechanical forces (e.g. occupational stress, obesity), or by a previous joint insult (e.g. trauma, rheumatoid arthritis).
Describe what hallmarks you might see on a radiograph that confirms your suspicion that your patient has osteoarthritis of the hip?
The hallmarks of DJD are joint space narrowing, sclerosis, and osteophytosis. If all three of these findings are not present on a radiograph, another diagnosis should be considered. Joint space narrowing is the least specific finding of the three, yet it is virtually always present in DJD. Unfortunately, it is also seen in almost every other joint abnormality.
A 92-year-old man presents to you complaining of hip pain, especially on lateral hip rotation. You suspect he has osteoarthritis.
You want to confirm that it is only osteoarthritis your patient is suffering from and you decide to perform a Trendelenberg’s Test to look at muscle and nerve function. How would you perform this test?
Ask the patient to stand on his/her “good” leg. The pelvis on the opposite side should elevate demonstrating that the gluteus medius and minimus are working efficiently. Now ask the patient to stand on the “bad” leg. The
pelvis on the opposite side will sag/fall indicating that the gluteal muscles are not working properly. This is termed as a positive Trendelenberg sign. If the patient is likely to lose balance or fall when standing on one leg (support may be needed) e.g. if a lower limb is unlikely to support their weight or if they have neurological problems affecting balance.
Damage to what nerve would cause a positive Trendelenberg’s sign?
Superior gluteal nerve.
Why would damage to the inferior gluteal nerve not cause a positive Trendeleberg’s sign?
Inferior gluteal nerve supplies gluteus maximus which acts on the hip joint - this muscle is a powerful extensor of the hip joint during activities such as brisk walking or running
Off of what plexus do the gluteal nerves originate from?
Describe their course as they come out of the pelvis and into the gluteal region?
The gluteal nerves (superior & inferior) originate from the lumbo-sacral plexus; their root values are L4 and S1. They exit the pelvis via the greater sciatic notch – the superior gluteal nerves above the piriformis, and the
inferior gluteal nerves below the piriformis muscle belly.
What major nerve is responsible for innervation of the perineum?
What are its three terminal branches?
Pudendal nerve
- Inferior rectal nerve
- Perineal nerve
- Dorsal nerve of the penis/clitoris
