SK-lecture 4- Knee joint

winniesmith2's version from 2018-05-19 12:01

Section 1

Question Answer
3 bones that articulate at kneefemur, tibia and patella (NOT fibula)
Name the ligaments in the knee (anterior view)Anterior cruciate ligament, Posterior cruciate ligament, lateral collateral ligament, medial collateral ligament
What are the names and function of menisciMedial and lateral meniscus. Functions; stability, lubrication, shock absorption.
What type of bone is the patella and what are its functionsA sesamoid bone. Functions; reduced patella tendon friction. Protects anterior knee structures from trauma. Acts as a lever- increases the lever arm of the quadriceps.
Name the types of movements at the kneeFlexion and Extension. Internal and external rotation, when leg is flexed
Describe the anatomy of the femurHas a greater trochanter, a lesser trochanter and a linea aspera.

Section 2

Question Answer
Name the 4 muscles that make up the quadriceps Rectus femoris, Vastus medialis, vastus lateralis, vastus intermedius (not superficial hidden under other muscles).
Rectus femoris O- anterior inferior iliac spine (AIIS). I- Tibial tuberosity (via the patella and patellar ligament).
Vastus medialisO- medial lip of linea aspera. I- Tibial tuberosity (via the patella and patellar ligament).
Vastus lateralis O- Lateral lip of linea aspera, gluteal tuberosity and greater trochanter. I- Tibial tuberosity (Via the patella and patellar ligament).
Vastus intermedius O- Anterior and lateral shaft of the femur. I- Tibial tuberosity (via the patella and patella ligament).
Name the muscles that make up the hamstringsBiceps femoris, semi tendinosus, semi membranosus
Biceps femorisO- Long head; ischial tuberosity. Short head; Lateral lip of linea aspera. I- head of the fibula.
semi tendinosusO- Ischial tuberosity. I- Proximal, medial shaft of the tibia at pes anserinus tendon.
semi membranosusO- Ischial tuberosity. I- Posterior aspect of medial condyle of tibia.
Name 4 other knee flexors Gastrocnemius, popliteus, sartorius, gracilis
Gastrocnemius O- condoles of the femur, posterior surfaces. I- calcaneus via calcaneal tendon.
PopliteusO- lateral condyle of the femur, I- Proximal, posterior aspect of tibia.
SartoriusO- Anterior superior iliac spine (ASIS) I- proximal,medial shaft of the tibia at pes anserinus tendon.
GracilisO- Inferior ramus of pubis. I- proximal, medial shaft of tibia at pes anserinus tendon.

Section 3

Question Answer
Describe the kinesiology of agonists and antagonistsMuscle groups exist in opposition. When agonist muscle(s) are activated, the nervous system tends to relax the antagonists – called Reciprocal Inhibition. However reciprocal inhibition may be incomplete, and the antagonists also generate torque. Movement depends on net torque: Gravitational Force (Fg) Tagonists vs Tg + Tantagonists.
Describe the kinesiology of biarticular muscles When a muscle with multiple joint actions is activated it attempts to shorten and pull the insertion towards the origin. Therefore when lifting the forearm, why does movement only occur at one joint? because eventhough equal forces are applied at the O & I, generating a torque at both joints, which attempts to perform all of its actions, when lifting the forearm there is a longer perpendicular distance from the pivot.
Describe the frontal plane deviations in knee positionGenu valgum (knock-knees) and genu varum (bow-legged).
Describe the quadriceps angle (Q-angle) Angle between the line of quadriceps (ASIS to midpoint of patella) and the line of the patella tendon  Males: 12-13º  Females: 15-18º
Describe chondromalacia patella (runner's knee)Pain beneath the patella. Mis-tracking of the patella and damage to the patello-femoral cartilage. Risk factors; Genu valgum & high Q angle. Eversion (pronation) of the foot. High patella. Weak vastus medialis.
Describe an ACL injury70% of all ACL injuries are non-contact. Thought to result from excessive anterior tibial translation.
According to video review of injuries; what causes an ACL injury  Injury typically occurs during cutting or landing movements  Relatively extended joint position, often with some knee valgus. Often very soon after ground contact.