Anatomy Dissection 5/6 - Knee, anterior and lateral leg Flashcards
What type of joint is the knee joint?
A synovial hinge joint
What are the 3 articulations of the knee?
2 between the femur and tibia; 1 between the femur and patella (fibula does not take part in the knee joint)
What are the main movements of the knee joint?
Flexion and extension (when flexed at 90 degrees, a degree of medial and lateral rotation is also achievable)
What are the main muscles and nerves involved in flexion of the knee joint?
Hamstrings & gastrocnemius
Tibial and common fibular nerve
What are the main muscles and nerve involved in extension of the knee joint?
Quadriceps
Femoral nerve
What are the main muscles and nerves involved in medial rotation of the knee?
Hamstrings & gracilis
Tibial and obturator nerves
Main muscles and nerves involved in lateral rotation of the knee?
Biceps femoris
Tibial & common fibular nerve
What does the knee joint have that attaches around the margins of the articular cartilage and encloses the synovial cavity?
A fibrous capsule
What strengthens the fibrous capsule of the knee?
Ligaments
What ligaments help to stabilise the knee joint?
Iliotibial tract
Tibial (medial) collateral ligaments
Fibular (lateral) collateral ligametns
Cruciate ligaments (anterior and posterior)
What are menisci?
Crescentic discs of fibrocartilage - act as shock absorbers as well as assisting with stabilisation of the curved femoral condyles upon the relatively flatter tibial condyles
What is the more well known name for Genu varum?
bow legs
What is the more well known name for genu valgam?
Knock knees
What do the menisci attach to?
Attach peripheral to the fibrous capsule
Medial meniscus is also attached peripherally to the tibial (medial) collateral ligament (therefore more vulnerable to tearing in a knee injury)
Anchored anteriorly and posteriorly to the tibial intercondylar area
What is the “unhappy triad” knee injury?
Partial or full tear of:
ACL
Medial collateral ligament
Medial meniscus
Where does the ACL pass in order to attach to the lateral femoral condyle?
Superiorly, laterally and posteriorly
What does the ACL prevent?
Anterior displacement of the tibia on the femur and hyperextension of the knee joint
What tests the integrity of the ACL?
The anterior drawer test or Lachmans test
Where does the PCL pass in order to attach to the medial femoral condyle?
Superiorly and anteriroly
What are the attachments of the ACL?
Intercondylar eminence of the tibia
Lateral femoral condyle
What are the attachments of the PCL?
Intercondylar eminence of the tibia
Medial femoral condyle
What does the PCL prevent?
Posterior displacement of the tibia on the femur and hyeprflexion of the joint
What tests the integrity of the posterior cruciate ligament?
Posterior drawer test
What are bursae?
Bursae are thin, lubricated cushions located at points of friction between a bone and the surrounding soft tissue, such as skin, muscles, ligaments and tendons
How does the supra-patellar bursa differ from the subcutaneous bursae?
It is an extension of the synovial cavity
What does the presence of the supra-patellar bursa do?
Reduces friction of the quadriceps tendon during knee movement
Where does the common fibular never enter the anterior leg?
From the popliteal fossa superficial to the neck of the fibula
What does the common fibular nerve divide into? Where?
The superficial fibular nerve
The deep fibular nerve
At the fibular neck
What does the superficial fibular nerve supply?
The muscle of the lateral compartment of the leg
The skin/ fascia of the dorsum of the foot
What does the deep fibular nerve supply?
The muscles of the anterior compartment of the leg
Skin of the first interdigital cleft
What do all muscles of anterior leg attach proximally to?
Tibia, fibula or interosseous membrane
What does the tibias anterior attach distally to?
Base of the 1st metatarsal and medial cuneiform
What does the extensor hallicus longus attach distally to?
Distal phalanges of the great toe
What does the extensor digitorum longus attach distally to?
All digits
What does the Fibularis Tertius attach distally to?
The base of the 5th metatarsal
What are the main actions of the anterior muscles of the leg?
Dorsiflexion of the ankle, great toe and digits
Inversion (tibialis anterior - in combination with tibialis posterior) and eversion (fibularis tetras with fibulas longus and brevis) of the foot
What separates the anterior and lateral compartment of the leg?
Anterior intermuscular septum
What muscles are contained within the lateral compartment of the leg?
Fibularis longus
Fibularis brevis
Where does fibularis longus attach?
Fibula proximally
Plantar surface of the bases of the 1st metatarsal
Where does the fibularis brevis attach?
Fibula proximally
Plantar surface of the 5th metatarsal
What are the main actions of the fibulas muscles (lateral leg)?
Eversion of the foot
