True or False: the femoral nerve travels through the femoral triangle outside of the femoral sheath.
(Provide the correct information if the statement is false)
TRUE. (FYI but not necessary to add: The femoral artery and vein and the lower limb lymphatics are enclosed within the femoral sheath, the femoral nerve is outside of it).
True or false: adductor longus participates in the floor of the femoral triangle.
(Provide the correct information if the statement is false)
TRUE. (FYI, but not necessary to add: The floor of the femoral triangle is formed by iliopsoas, pectineus and adductor longus. The medial border of longus creates the medial border of the triangle. Or we could define the medial border as the lateral/anterior border of gracilis, and the lateral border is created by the medial margin of sartorius. As discussed in class yesterday, there are lots of ways to describe the region).
What is the functional significance of the valgus angle of the knee?
It places the knees in the midline of the body which helps reduce vertical and horizontal fluctuations of the center of mass during bipedal locomotion, thereby conserving energy.
However, it also orients the thigh muscles along that same angle, which results in a lateral pull on the patella. This pull can cause patellar instability.
True or false (if false, provide the correct information): muscles in the posterior compartment of the thigh extend the leg at the knee.
FALSE. muscles in the posterior compartment of the thigh flex the leg at the knee.
What is the primary source of innervation in the medial compartment of the thigh and which muscles are the exceptions?
The obturator nerve (and ts branches) supplies most of the medial compartment of the thigh. Pectineus and the hamstring portion of adductor magnus are the exceptions.
List the primary arterial branches of the deep artery of the thigh
1) medial circumflex femoral artery
2) lateral circumflex femoral artery
3) perforating arteries (1st-3rd or 4th)
Select the statement(s) that best associate(s) structures to their communicating region:
B)
Using anatomical landmarks, derive the path of the medial circumflex femoral artery between its origin and the abdominal aorta.
1) The abdominal aorta travels anterior to the spinal column as it approaches the lumbar region, and bifurcates at L4/L5
2) bifurcates into the right and left common iliac arteries
3) The common iliacs travel laterally and distally toward the SI joint where each bifurcates into an internal and external iliac artery
4) the external iliac artery travels distally toward the inguinal ligament and passes deep to it to enter the anterior compartment of the thigh
5) in the thigh, it is renamed the femoral artery
6) It enters the thigh midway between the pubic tubercle and the ASIS, between the vein and the nerve and travels in the femoral triangle within the femoral sheath
7) the deep artery of the thigh branches from the femoral artery near the proximal aspect of the femoral artery, approximately at the level of the lesser trochanter
7) the medial circumflex femoral artery is generally the first branch from deep femoral and comes off posteromedially, then dives deep to wrap around the posterior aspect of the femur
Derive the arterial path of the medial circumflex femoral artery starting at the abdominal aorta, do not include landmarks.
Abdominal aorta/left or right common iliac arteries/external iliac artery/femoral artery/deep artery of the thigh/medial circumflex femoral artery
When are psoas major and iliacus active during the walking gait and under what circumstances?
Essential information: They are active during the initial swing period but only when you are not walking at your optimal speed (i.e., either walking faster or slower than optimal).
Additional contextual information:They are active during the initial swing period when you are not walking at your optimal speed (speeding up or slowing down). When walking outside of your optimal speeds, the smooth exchange between potential and kinetic energy is interrupted, necessitating additional muscular contribution. Hence, iliacus and psoas major (and sartorious) will contribute.
Derive the afferent pathway between the appropriate place in the spinal cord and sartorius. Indicate either the starting or ending point. Do not include landmarks.
Sartorius (starting point) /femoral nerve/anterior rami of L2 & L3 / spinal nerves of L2 & L3 / posterior roots at L2 & L3 / Posterior white columns at L2 & L3 / Posterior grey horns at L2 & L3
Derive an efferent impulse pathway between a stretch spindle in adductor longus and the appropriate location in the spinal cord. Indicate either the starting or ending point, do not include landmarks.
start: anterior grey horn at L2, L3, L4 / anterior white column at L2, L3, L4 / spinal nerves at L2, L3, L4 / anterior rami at L2, L3, L4 / obturator nerve / anterior branch of obturator nerve / stretch spindle in adductor longus
Derive an afferent impulse from the short head of biceps femoris between the target and the appropriate location in the spinal cord. Indicate start or end points, do not include landmarks.
start: short head of biceps femoris / common fibular nerve / sciatic nerve / anterior rami of L5, S1 and S2 / spinal nerves of L5, S1, and S2 / posterior roots of L5, S1, and S2 / posterior white columns of L5, S1, and S2 / posterior grey horns of L5, S1, and S2
What are the spinal levels of iliacus?
L2 and L3
List all of the muscles in the thigh that insert along the linea aspera
1) adductor brevis
2) adductor longus
3) adductor magnus, adductor portion
True or false (if false, provide the correct information): all of the muscles in the anterior compartment are active during terminal swing. Provide the functions of each during this period
.
FALSE. the quads are acting to extend the leg at the knee. But none of the other muscles in the anterior thigh act during terminal swing.
Give the function of biceps femoris and explain why the muscle is able to participate in each action.
Short and long head: flex the leg at the knee and laterally rotates the leg at the knee. Both muscles cross posterior to the knee joint, so both are able to flex the knee. Their medial origin relative to their lateral insertion enables them to slightly laterally rotate when the fibers contract. But they will not do so on their own. Only with other lateral rotators are active.
Long head ONLY: extend the thigh at the hip joint and laterally rotate the thigh. Long head also crosses posterior to the hip joint, so it is able to act on the thigh.
Lateral rotation of the leg and thigh occur because the fibers travel posteriorly and laterally through the thigh and when they contract, the leg and thigh are pulled posteriorly and laterally, resulting in lateral rotation.
LH can also extent the trunk when the foot is on the ground, enabling it to pull from the insertion onto the origin on the pelvis, passing posterior to the hip joint.
If all L2 contributions to the femoral nerve were non-functional would you be able to extend the leg at the knee? Explain your answer
Essential information: Yes because the muscles that extend the leg at the knee also receive spinal fibers from L3 and L4 in the femoral nerve and they would remain functional.
Additional contextual information:Function would likely be compromised to some degree b/c of the loss of L2, but the muscle would most likely remain functional.
If all of the fibers contributing to the femoral nerve were non-functional at the point of convergence, would you be able to flex your thigh at the hip joint? In your response provide the following information:
A) Which relevant muscles are non-functional and why
B) Which relevant muscles compromised
C) Which relevant muscles are completely functional and why
C) Psoas major remains completely functional b/c it is innervated by the anterior rami of L1, L2, and L3, but those fibers are distinct from the fibers that make up the femoral nerve
So yes, hip flexion remains possible but it is also highly compromised.
True or false: All four of the quadricep femoris muscles can extend the leg at the knee and flex the thigh at the hip. Explain your answer.
FALSE: only rectus femoris can act on the thigh because it is the only muscle that crosses the hip joint.
True or false: The two heads of biceps femoris are the straight head and the long head.
FALSE: the heads are the long head and the short head.
List the muscles in the posterior compartment of the thigh.
1) biceps femoris, short head and long head
2) semitendinosus
3) semimembranosus
What are the spinal levels of the sciatic nerve?
the inferior half of L4-S3
What are the primary divisions of the sciatic nerve and what are their spinal levels?
Tibial: inferior half of L4 - S3
Common fibular: inferior half of L4 - S2
True or false: Both heads of bicpes femoris insert into the head of the fibula.
TRUE
Derive the arterial path of the superior blood supply of the psoas major mucle back to the abdominal aorta.
Psoas major / lumbar arteries / abdominal aorta
What type of joint is the knee joint?
A synovial hinge joint or a bycondylar synovial joint
True or false: the proximal tibiofibular articulation is NOT a part of the knee joint.
True
What is the primary weight-bearing articulation of the knee joint?
The articulation between the distal femur and the proximal tibia
True or false: The menisci are connected to the tibial plateau along their entire inferior surfaces.
Essential information: FALSE. The inferior inner surfaces of the menisci are left unattached which allows synovial fluid to bathe the inferior surface, providing them with nutrients and helping reduce friction.
Additional contextual information:They are attached at the horns and the perimeters, but not along the inferior surface.
Describe the relationship between the medial meniscus and the fibrous joint capsule of the knee, as well as the functional significance of this relationship.
The medial meniscus is attached to the fibrous joint capsule of the knee and to the medial collateral ligament. Consequently, the medial meniscus is less mobile compared with the lateral meniscus. This relative immobility may be the reason that the medial meniscus is torn more frequently than the lateral.
List the ligaments of the knee that are included within the synovial membrane of the knee joint.
None of them are included within the synovial membrane.
List four ligaments of the knee joint
1) Tibial collateral ligament (AKA medial collateral ligament, both are fine)
2) fibular collateral ligament (AKA lateral collateral ligament, both are fine)
3) Anterior cruciate ligament
4) posterior cruciate ligament
5) Patellar ligament
6) oblique popliteal ligament
7) transverse ligament
8) Anteriolateral ligament
Describe the function of the quadriceps femoris muscle during the walking gait, including the periods during which it is active and the muscles that are acting with it.
The quads (vastus lateralis, vastus medialis, rectus femoris and vastus intermedius) are active during initial contact, loading response and terminal swing. No other muscles act with the four quadriceps to perform the same action.
During initial contact and loading response they are acting to prevent flexion of the leg at the knee joint. During terminal swing, they are acting to actively extend the leg at the knee.
The following statement(s) is/are true regarding the walking gait:
A) Forefoot rocker occurs during pre-swing
B) The body’s center of mass reaches its peak height during mid-stance
C) Gastrocnemius and soleus act during loading response to restrain the forward rotation of the leg about the ankle
D) Gluetus minimus and gluteus medius pull the stance side pelvis onto the stance side leg while the swing side leg is not in contact with the ground
E) The lower limb passes beneath the body during initial swing
B&D
A)Derive the path of general somatic efferent nerve fibers from the spinal cord to a generic limb target, including transitions and unions and divisions along the way
B) state what type of signal these fibers carry and their potential targets
A) The impulse originate in the anterior grey horn of the spinal cord. They then travel to the anterior white column. They exit the spinal cord via the ventral/anterior root. Join with fibers from the posterior root to form the spinal nerve. The spinal nerve divides into the posterior and anterior rami and the fibers continue via the anterior ramus and proceed out to their intended muscular target.
B) GSE fibers carry motor impulses from the CNS to the skeletal muscles, skin, and joints.
The anterior roots at levels L4 and L5 are rendered completely non-functional. Which muscles in the gluteal region and thigh will be:
A) completely non-functional
B) compromised, but still functional. Also give spinal levels of these muscles
For each muscle, list their associated spinal levels
A) Entirely non-functional:
no muscles are completely non-functional
B) Compromised:
G. Max (L5, S1, S2)
G. Med and Min (L4, L5, S1)
TFL (L4, L5, S1)
the gemelli, obturator internus & quadratus femoris (L5, S1)
