Lower Limb 2 Flashcards
What is the pelvic girdle?
Bony ring consisting of the sacrum and right and left hip bones
Joined anteriorly at pubic symphysis and posteriorly at sacroiliac joints
What does the pelvic girdle consist of?
Two hip bones, sacrum, coccyx
What are the 4 articulations of the pelvic girdle?
Sacroiliac joints
Pubic symphysis
Sacrococcygeal symphysis
What is the greater sciatic foramen a route for?
Structures entering/leaving the pelvis
What is the lesser sciatic foramen a route for?
Structures entering/leaving the perineum
What muscles are in the superficial layer of the gluteal region?
Gluteus maximus
Gluteus medius
Gluteus minimus
Tensor fasciae latae
What is the nerve supply to tensor fascia latae, gluteus minimus and medius?
Superior gluteal nerve
What are the nerve roots of the superior gluteal nerve?
L4-S1
What muscles are in the deep layer of the gluteal region?
Piriformis Obturator internus Superior gemelli Inferior gemelli Quadratus femoris
What is the fascia lata?
Deep fascial investment of the whole thigh, beginning proximally around the iliac crest and ending at the bony prominences of the tibia
What is the iliotibial tract?
Longitudinal thickening of the fascia lata (strengthened from fibres of the gluteus maximus)
What muscles attach to the iliotibial tract?
Thickened aponeuroses or the tensor fascia latae and gluteus maximus
On what muscle does the sacral plexus sit?
Piriformis
What are the nerve roots making up the sacral plexus?
S1-4 and L4-5 makes it the lumbosacral plexus
What are the main branches of the sacral plexus?
Sciatic and pudendal nerve
What are the other branches of the sacral plexus?
Superior and inferior gluteal
Posterior femoral cutaneous
Nerve to piriformis, nerve to quadratus femoris, nerve to obturator internus, nerve to levator ani and coccygeus
What is the innervation of gluteus maximus?
Inferior gluteal nerve
What are the nerve roots of the inferior gluteal nerve?
L5-S2
What are the nerve roots of the sciatic nerve?
L4-S3
From where does the sciatic nerve emerge?
Inferior to the piriformis
What are the two terminal branches of the sciatic nerve?
Common fibular and tibial nerve
What is the action of the sciatic nerve?
Innervates all posterior thigh and hamstring portion of adductor magnus and all lower leg and foot by its terminal branches
What are the muscles making up the hamstrings (L–>M)?
Biceps femoris (long and short head)
Semitendiosus
Semimembranosus
What are the actions of the hamstrings?
Extend the hip and flex the knee
Biceps femoris also laterally rotates the hip and knee
Semitenidosus/semimembranosus also medially rotate the hip and knee
What innervates the hamstrings?
Sciatic nerve
What kind of joint is the knee?
Synovial hinge
What actions can occur at the knee joint?
Flexion and extension
Small active and passive rotations
What are the articular surfaces of the knee?
Medial and lateral condyles of the femur
Tibia
Posterior surface of the patella
2 femorotibial articulations (M and L) between the lateral and medial femoral and tibial condyles and 1 femoropatellar articulation between the patella and femur
What bone is not involved in the knee joint?
Fibula
What does the stability of the knee depend on?
Strength and action of surrounding muscles and their tendons
Ligaments connecting the femur and tibia
What is the most important thing that stabilises the knee?
Quadriceps femoris (esp vastus medialis and lateralis)
What are the ligaments of the knee joint thickenings of?
The joint capsule
What are the ligaments of the knee?
Fibular/lateral collateral
Tibial/medial collateral
ACL and PCL
Where does the fibular collateral ligament extend from?
Lateral epicondyle of femur to the lateral surface of the head of the fibular
Where does the popliteus tendon pass?
Deep to the LCL and separates it from lateral meniscus
Where does the tibial collateral ligament extend from?
Medial epicondyle of femur to medial condyle and upper part of the medial surface of the tibia
What is the MCL attached to?
At its midpoint firmly attached to medial meniscus
Tearing of MCL can lead to tearing of medial meniscus as a result
What is the appearance of the cruciate ligaments?
Cross to form an X
What is the function of ACL?
Prevent femur sliding posteriorly on the tibia and prevents posterior dislocation and hyperextension of the knee
What is the function of the PCL?
Prevents femur sliding anteriorly on the tibia
Why is the ACL more prone to injury and hard to repair?
Weaker than PCL
Poorer blood supply
What are menisci?
C shaped plates of fibrocartilage on the articular surface of the tibia
How can you distinguish between the lateral and medial menisci?
Medial - C shaped and firmly attached to deep surface of MCL
Lateral - circular, no attachment and therefore more mobile
What are the functions of the menisci?
Deepen articular surface of tibia –> increased stability of joint
Act as shock absr
What are the functions of the menisci?
Deepen articular surface of tibia –> increased stability of joint
Act as shock absorbers by increasing SA to further dissipate forces
What is the unhappy triad?
Impacts to knee generally come from lateral direction putting stress on medial collateral ligament, ,which tears in turn tearing the medial meniscus
This puts a bit load on ACL which also tears
Leading to the three injuries
What movements occur at the knee joint?
Flexion
Extension
What are the flexors of the knee joint?
Hamstrings
Gracilis
Sartorius
Popliteus
What are the extensors of the knee joint?
Quadriceps femoris
What muscles make up the quadriceps femoris?
Vastus lateralis, vastus medialis, vastus intermedius, rectus femoris
What are bursae?
Synovial fluid filled sacs between moving structures
What are the four bursae in the knee?
Suprapatellar
Prepatellar
Infrapatellar
Semimembranosus
What bursa communicates with the synovial cavity of the knee? What is the clinical significance of this?
Suprapatellar
Abrasions/penetrating injuries superior to patella may result in suprapatellar bursitis which may allow bacteria to spread to the knee joint
What is bursitis?
Infection and inflammation of the bursa
What is bursitis?
Infection and inflammation of the bursa
E.g. housemaids knee
