Review of the Lower Limb Flashcards
what is shentons line
Shenton lineis an imaginary curved line drawn along the inferior border of the superior pubic ramus (superior border of theobturator foramen) and along the inferomedial border of the neck offemur
what does interruption of Shentons line mean
- interruption of the shenton line can indicate a fracture of the neck of the femur
what type of joint is the hip joint
ball and socket synovial joint
what is the acetabulum made up of
- ilum
- Ischium
- pubis
describe the hip joint
- made out of the acetabulum which is where the head of the femur sits into the hip
describe what the top part of the femur is made out of
- femoral head
- femoral neck
- greater and lesser trochanters
what three ligaments surround the hip joint
- pubo-femoral ligament
- Iilo- femoral ligament
- ishcio-femoral ligament
what is the strongest ligament supporting the hip joint
- Iilo-femoral ligament
- crosses the anterior aspect of hip joint therefore the anterior part is reinforced more than the posterior part
what is the ligament in the hip joint itself
ligamentum teres
what are ligaments supporting the hip joint like in flexion and extension
Flexion
- lax - fibres are straight
extension
- taut - fibres are twisted
when is the hip most stable
= extension - all the ligaments supporting the hip are taut when the hip is in extension
in which direction do the vast majority of hip dislocations occur
- they occur posteriorly when the hip is flexed
- for example in a car crash where the dash board hits the knee and this can push the femur out of hte hip joint posteriolry
what percentage of hip dislocations are posterior
86-90%
what is more common hip dislocation or fracture
Hip fractures are more common
describe the blood supply of the femur
- The femoral artery gives of the perfunda femoris
- the perfunda femoris gives on the medial and lateral circumflex artery
- the medial and lateral circumflex arteries give of retinacular arteries which pierce the femoral neck and go into the femur and supply the bone with blood
- also have an branch of thee obturator artery which supplies the head of the femur
describe what direction the medial and lateral circumflex go
medial = wraps anteriorly around lateral = wraps posteriorly around
what arteires are important to the supply of the femur neck and head
- the medial and lateral circumflex arteries give of retinacular arteries which pierce the femoral neck and go into the femur and supply the bone with blood
- also have an branch of thee obturator artery which supplies the head of the femur
what are the two types of femoral head and neck fractures
= intracaspular fracture and extracapsular fracture
what is the difference between intracapsular fracture and extracapsular fracture
Intracapsular
- Intracapsular femoral fracture happens in the capsule part
- higher risk of avascular necrosis
extracapsular
- outside of the capsule part
- happens lower in the neck
- lack of risk of avascular necrosis - arteries will be in tact
in a hip dislocation posteriorly what structures are at risk
sciatic nerve
in a hip dislocation anterior what structures are at risk
femoral artery
obturator artery and nerve
what makes up the greater sciatic foramen
– sacrotuberus and the illiac crest
What makes up the lesser sciatic foramen
= sacrospinous and sacrotuberous
What does the sacrospinous ligament attach to
- attaches to the sacrum and the ischial spine
What does the sacrotuberous ligament attach to
- attaches to the sacrum and the ischial tuberosity
what leaves the greater sciatic foramen
- superior gluteal neurovascular
- inferior gluteal neurovascular
- piriformis
- sciatic nerve
- pudendal
What leaves the lesser sciatic foramen
Pundendal nerve
where do you do an IM injection
high up in the hip in order to avoid all of this neurovascular within the gluteal region
when are the three muscles that make up the gluteals
- Gluteus maximus
- Gluteus medius
- Gluteus minimus
Describe the gluteus Maximus
- innervation
- movement
- insertion point
- largest and most superficial
- innervated by the inferior gluteal nerve
- hip extensor and lateral rotator
- inserted 3/4 iliotibial band and 1/4 of gluteal tuberosity of femur
describe the tensor fascia lata
- innervation
- movement
Tensor fascia lata
- innervation= superior gluteal nerve
- abduction of the hip
Describe gluteus medius
- innervation
- movement
- innervation= superior gluteal nerve
- abduction of the hip and stabilization of the pelvis
Describe gluteus minimus
- innervation
- movement
- innervation= superior gluteal nerve
- abduction of the hip and stabilization of the pelvis
What muscles do abduction of the hip
- tensor fascia lata
- gluteus medius
- gluteus minimus
what do the lateral rotators do
- innervation
- these are involved in the lateral rotation of the hip
- L5, S1, S2 - have there own individual branches
what does piriformis do and what is it supplied by
- lateral rotation of the hip
- nerve piriformis
name the lateral rotators
Superior gemellus
inferior gemellus
obturator inturnus
quadratus femoris
piriformis
describe the trendeleburg test
- idea that gluteus medius and minimus keep the pelvis straight when standing on one leg by contracting on the opposite side to which the leg is elevated.
what does damage to the gluteus medius and minimus result in
- results in a positive trendeleburg test
- the gluteal nerve can cause contralateral hip drop as the gluteus medius and minimus can no longer support the hip on the opposite side
what three compartments is the thigh divided into
anterior
medial
posterior
describe the anterior compartment of the thigh
- innervation
- muscle
- movement
Femoral nerve (L2,3,4)
Quadriceps
Knee extension and hip flexion (a bit)
describe the medial compartment of the thigh
- innervation
- muscle
- movement
Obturator nerve (L2,3,4)
Adductors
Hip adduction
describe the posterior compartment of the thigh
- innervation
- muscle
- movement
Sciatic nerve- Tibial branch (L5,S1,S2)
Hamstrings
Knee flexion and a bit of hip extension
What is at the midpoint on the inguinal ligament
femoral artery
what muscles are in the anterior compartment of the hip
Iliopsoas (Psoas major and Iliacus)
sartorius
Qaudriceps
What movement does illiopsoas do
(Psoas major and Iliacus)
Major flexor of the hip joint
What movement does sartorius do
flexes hip and knee
Name the four quadriceps
Vastus medialis,
Vastus lateralis
medialis
Rectus femoris
where do all hamstrings originate from
the ischial tuberosity and they attach onto the tibia (only long head of bicep femoris not the short head)
what movement do hamstrings do
flex the knee joint
what are the three hamstrings
Semitendinosus
Semimembranosus
Biceps femoris (long head and short head)
what are the hamstrings innnervated from
Innervated by tibial division of the sciatic nerve
What makes up the medial compartment
adductors
name the 4 adductors
Adductor Magnus
Adductor Longus
Adductor Brevis
Gracilis
What are the adductors innervated by
- innervated by the obturator nerve (other than the hamstring part of adductor magnus)
What are the attachment point of the adductor muscles
In general they attach to the pelvis and distally to linea asperea.
What three muscles is the pes anserinus an attachment point for
Sartorius
Gracilis
Semitendinosus
what are the nerve roots of the obturator nerve
L2-4
What are the nerve roots of the femoral nerve
L2-4
What is the femoral triangle made up of
- Superior inguinal ligament
- laterally Sartorius
- inferiorly adductor longus
what is in the femoral triangle
- femoral Nerve
- femoral artery
- femoral vein
- lymphatics
who is more likely to get a femoral hernia
= Women
- this is because the inguinal canal is not as developed
what passes through the adductor canal
- the femoral artery passes through the adductor hiatus and becomes the popliteal artery
what are the three articulations in the knee
lateral femoral and tibial condyles with corresponding meniscus
medial femoral and tibial condyles with corresponding meniscus
patella and femur
what is the largest joint in the body
The knee
what bone is not involved in the knee
- fibula
What does the knee depend on for strength
- relatively weak joint on its own so it depends on ..
1. Strength and actions of surrounding muscles and their tendons
2. The ligaments that connect the femur and tibia
describe the medial meniscus
larger than the lateral meniscus
C-shaped
Broader posteriorly than anteriorly
Anteriorly attached to ACL
Firmly adhered to the tibial collateral ligament
describe the lateral meniscus
Nearly circular
Smaller and more freely movable than medial meniscus
Attached to the PCL.
what are the two collateral ligaments supporting the knee
- fibular collateral ligament (lateral side) - independent of the knee joint capsule
- tibial collateral ligament (medial side)
describe the attachement point of the PCL
Runs from posterior aspect of intercondylar area of tibia and ascends anteriorly to attach to the medial wall of the femoral intercondylar fossa
What does the PCL do
Stops tibia moving backward on femur
Helps stabilise knee especially in flexion
Also prevents tibia twisting outward (external rotation)
what is stronger the PCL or ACL
PCL
describe the attachment points of the ACL
Runs from facet on the anterior part of the intercondylar area of tibia and ascends posteriorly to attach to the back of the lateral wall of the intercondylar fossa of the femur
What does the ACL do
Stops tibia moving forward on femur
Stabilise knee in extension and prevents hyperextension and excessive internal rotation
What is the unhappy triad
Made up of the:
- medial mensici
- ACL
- tibial collateral ligaments
- this is because they are all attached to each other therefore if you tear one then the others are likely to be torn
When does a ACL tear often occur
ACL tearing often occurs when the knee is twisted whilst that limb is weight bearing with the foot fixed on the ground
what resutls from an anterior and posterior drawer sign
Anterior drawer sign
- ACL prevents the femur sliding posterior on the tibia so rupture results in the anterior drawer sign
Posterior drawer sign
- The PCL prevents the femur sliding anteriorly on the tibia, so rupture results in the posterior drawer sign
what are the borders of the popliteal fossa
= semimembranous and semitendinous
- gastrocnemius
What goes through the popliteal fossa
- common peroneal nerve
- tibial nerve
- sural nerve
- small saphenous vein
- popliteal artery and vein
where does the small saphenous vein drain into
- the popliteal vein
describe the blood supply to the knee
- have the popliteal artery and this gives of the superior and inferior genicular artery
what compartments is the leg made out of
- anterior
- lateral
- posterior
describe the anterior compartment of the leg
Deep peroneal nerve
Dorsiflexion
Extension of digits
describe the lateral compartment of the leg
Superficial peroneal nerve
Eversion
Describe the posterior compartment of the leg
Tibial nerve
Plantarflexion
Flexion of digits
describe the blood supply to the leg
popliteal artery then divides into an anterior and posterior tibial
Anterior tibial goes through interssous membrane into anterior comarpetmn of the leg and anterior part of the ankle and becomes the dorsalis pedis
posterior tibial goes into the posterior compartment and behind the medial malleolus into the sole of the foot where it becomes the medial and lateral plantar artiereis
lateral compartment
- perforating branches of the deep peroneal (fibular)
where is the dorsalis pedis pulse
- lateral to flexor hallicus longus
describe the nerve supply of the lower leg
the sciatic nerve divides into the tibial and common peroneal nerve
- the common peroneal divides into the superficial personal nerve and deep peroneal nerve
what does the superficial and deep peroneal nerve supply
Superficial peroneal nerve = lateral compartment
Deep peroneal nerve = anterior compartment
what does the tibial nerve supply
Tibial nerve – continues in posterior compartment and innervates it
what bone does the common peroneal wrap around
fibular - gets damaged if the fibular bone gets damaged
what happens if you have a common peroneal injury
foot drop
what does the common peroneal nerve innervate
The common peroneal nerve innervates the muscles of the anterior compartment of the leg (dorsiflexion) and the lateral compartment of the leg (eversion).
what causes a common peroneal nerve injury
damage to the head of the fibular
what supplies the sensory innervation to the sole of the foot
tibial nevre
what type of joint is the ankle joint
hinge synovial joint
what is the ankle joint formed from
synovial joint between tibia, fibula and talus bones.
what movements can the ankle joint do
- plantarflexion and dorsiflextion
What movements does the subtalor joint do
eversion and inversion
what are the two types of ligament of the ankle joint
lateral and medial
name the 3 lateral ligaments
Anterior talofibular ligament
Posterior talofibular ligament
Calcaneofibular ligament
name the medial ligament
deltoid
what is the most common ligament to be sprained
Anterior talofibular ligament
what joint does eversion and inversion
subtalor joint
