Inside major lower limb joints Flashcards
Teres
Sausage-shaped
Valgus
Deformity away from midline
Varus
Deformity towards midline
Genu valgus
Knock-knees
Genu varus
Bow legs
Coxa valgus
Increased angle between femoral neck and shaft
Coxa varus
Angle between femoral head and shaft is less than 120 degrees
Ligaments
Connect bone to bone
What is the innominate bone made from?
Ischium, ilium and pubic bone
What is the acetabulum fossa?
Depressed articular surface where bones meet
What are the trochanters?
Two tubercles, have greater and lesser trochanters
What is the trochanteric crest?
Connects trochanters
What is the intertrochanteric fossa?
Gap between condyles
Key features of innominate bone
- Acetabular fossa
- U-shaped articular surface
- Superior pubic ramus
- Anterior iliac spine
- Ischial tuberosity
Key features of femur
- Head
- Neck
- Greater and lesser trochanters
- Intertrochanteric line
- Intertrochanteric crest
- Linear aspera
- Medial and lateral condyles
- Medial and lateral epicondyles
- Intercondylar notch
What are the two intracapsular hip ligaments?
Transverse acetabulum ligament
Ligamentum teres
Where is the ligamentum teres?
Behind transverse acetabular ligament, supplies blood to femoral head and connects it to hip
What does transverse acetabular ligament do?
Joins acetabulum together
What are the extra capsular hip ligaments?
Iliofemoral ligament
Pubofemoral ligament
Ischiofemoral ligament
What does iliofemoral ligament do?
Prevents hyperextension of the hip
What does pubofemoral ligament do?
Reinforces capsule, limits abduction
What does ischiofemoral ligament do?
Holds femoral head in acetabulum, extension to 20 degrees
What are the main sources of blood to the head of the femur?
Artery inside ligamentum teres
Reticular branches
Osteological arteries
What is the main blood supply of the head of the demur in children?
Artery inside ligamentum teres - growth plate blocks reticular branches
What is the main blood supply of the head of the femur in adults?
Reticular branches - growth plate replaced by Haversian bone
From what type of fractures does AVN of the femoral head commonly occur?
Subcapital neck, transcervical and intertrochanteric fractures
What happens when the neck of the femur is fractured?
Proximal femur: no movement
Distal femur: pulled proximally (quadriceps and hamstrings) and laterally (lateral rotators and gluteus Maximus)
What happens when the shaft of the femur is fractured?
Proximal femur: generally neutral
Distal femur: pulled proximally (quadriceps and hamstrings) and posteriorly (gastrocnemius)
What is Legg-Cathe-Perthes disease?
- Idiopathic osteonecrosis of capital femoral epiphysis
- Idiopathic avascular necrosis of femoral head
Characteristics of Legg-Cathes-Perthes disease
- Common between 5-10 years
- First symptoms include pain and a limp
- Shortening of leg
- Osteoarthritis develops later
- More common in males than females
- One leg starts and the other follows
- Limited range of motion
Key features of the knee
- Medial and lateral supracondylar ridges
- Medial and lateral condyles
- Medial and lateral epicondyles
- Popliteal surface
- Intercondylar notch
- Medial and lateral tibial plateaus, anterior and posterior intercondylar areas
- Intercondylar eminece
- Facet for head of fibula
- Tibial tuberosity - caused by quads pulling on tibia
What is Osgood-Schlatter syndrome?
Inflammation of patellae ligament at tibial tuberosity
What are the boundaries of the joint capsule?
- Proximal femoral condyles and intercondylar fossa posteriorly
- Patellar retinaculum anteriorly
- Articular margin of femur marginally
- Femur laterally
What are the five ligaments in the knee?
- Patella ligament
- Anterior cruciate ligament
- Posterior cruciate ligament
- Medial collateral ligament
- Lateral collateral ligament
What does patella ligament do?
Attaches patella to tibial tuberosity
How is patella ligament injured?
Direct impact to front of knee
How to test integrity of patella ligament
Tense and relax quads
What does ACL connect?
Femur to tibia
What does ACL do?
Restricts anterior movement of tibia relative to femur
How to test ACL?
Pull tibia anteriorly
How is ACL torn?
Sport
What does PCL connect?
Femur to tibia
What does PCL do?
Restricts posterior movement of tibia relative to femur
How to test PCL?
Holding knees and hips at 90 degrees with foot in the air. Posterior sag in knee indicated PCL tear
How to tear PCL?
Direct blow to front of knee when it is bent
What does the medial collateral ligament connect?
Femur to tibia
How is medial collateral ligament torn?
Direct blow to knee
How is medial collateral ligament tested?
Bend affected leg to 30 degrees of flexion whilst applying valgus force. Positive test occurs when pain occurs
What does medial collateral ligament do?
Prevents leg extending inwards, keeps knee stable and allows it to rotate
How is lateral collateral ligament torn?
Twisting on side of foot
What does lateral collateral ligament connect?
Femur to fibula
What does lateral collateral ligament do?
Provides knee with stability
How to test integrity of lateral collateral ligament
Varus stress test - bend knee to 30 degrees flexion whilst applying varus force. Positive test occurs when pain occurs
Which muscles are used to extend the knee?
Quadriceps femoris
Which muscles are used to flex the knee?
Hamstrings and gracilis, gastrocnemius and sartorius
Where is the cartilage in the knee?
Meniscus behind patella
Function of meniscus
Donut shaped to increase surface area between condyles and tibial plateaus
How can you damage cartilage in knee?
Twist knee whilst bearing weight on it
What are the two meniscus in the knee?
Medial and lateral (medial more susceptible to injury)
