Posterior Thigh

Question 1

Muscles in posterior compartment known as

Answer 1

Hamstrings

Question 2

Hamstrings consist of…
What do the form?

Answer 2

Bicep femoris
Semitendinosus
Semimebranous muscle

(Form tendons medially and laterally at back of knee)

Question 3

Hamstrings muscle act to…

Answer 3

Extend lower limb at hip, flex it at the knee

Question 4

Hamstrings innervated by…
What is the exception?

Answer 4

Tibial part of sciatic nerve

except short head of biceps femoris = innervated by common peroneal part of sciatic nerve

Question 5

Biceps femoris

Answer 5

2 heads - long head and short

Tendon can be palpated laterally on posterior knee)

Question 6

Long head bicep femoris

Answer 6

Originates: ischial tuberosity

Insert: head of fibula

Action: flex the knee, extend thigh at hip, laterally rotates hip and knee

Innervation: Tibial part sciatic nerve

Question 7

Short head bicep femoris

Answer 7

Originates: linea aspera (posterior femur)

Inserts: head of fibula

Action: The main action of biceps femoris is to flex the knee. It also extends the thigh at the hip, and laterally (externally) rotates the hip and knee

Peroneal (fibular) part of sciatic nerve

Question 8

Semitendinous

Answer 8

Tendonous muscle
Medial to biceps femoris, superficial semimembranous

Originates: ischial tuberosity

Inserts: upper medial aspect tibia (pes anserinus)

Action: flexes leg at knee, extends thigh at hip, medially rotates thigh at hip, medially rotates leg at knee

Innervation: tibial part of sciatic nerve

Question 9

Semimembranosus

Answer 9

Flat, broad tendon origin

Originates: ischial tuberosity

Inserts: medial tibial condyle

Actions: flexes knee at joint, extends thigh at hip, medially rotates thigh at hip, medially rotates leg at knee (SAME AS OTHER SEMI)

Innervation: tibial part of sciatic nerve

Question 10

Hamstring injury

Answer 10

• A pulled hamstring tends to occur during sudden muscular exertion that results in stretching of the posterior thigh muscles e.g. jumping, sprinting and lunging.
• It is relatively common in footballers and athletes, especially if proper warm-up exercises have not been performed beforehand.
• Sudden tension on the hamstrings results in either a muscle sprain, a partial tear or a complete tear of the hamstring muscles from the origin (ischial tuberosity), sometimes accompanied by avulsion of a fragment of bone.

Question 11

Where is semi membranosous and teninosous located?

Answer 11

Semi Membranosous = MMedial side

Semi tendinosoous = on TTop