Posterior thigh Flashcards
What are the hamstrings innervated by
Sciatic nerve (L4-S3)
What are the muscles in the posterior thigh
Biceps femoris,
Semitendinosus,
Semimembranosus
Action of hamstrings
Flexion at knee and extension at hip
Origin of biceps femoris
Long head - Ischial tuberosity of pelvis
Short head - Linea aspera on posterior femur
Actions of biceps femoris
Knee flexion,
Hip extension,
Lateral rotation at hip and knee
Innervation of biceps femoris
Long head - tibial part of sciatic nerve
Short head - common fibular part of sciatic nerve
Origin of semitendinosus
Ischial tuberosity of pelvis
Attachment of biceps femoris
Head of fibula
Attachment of semitendinosus
Medial tibia
Actions of semitendinosus
Knee flexion,
Hip extension,
Medial rotation at hip and knee
Innervation of semitendinosus
Tibial part of sciatic nerve
Origin of semimembranosus
Ischial tuberosity of pelvis (more superiorly than others)
Attachment of semimembranosus
Medial tibial condyle
Action of semimembranosus
Knee flexion,
Hip extension,
Medial rotation at hip and knee
Innervation of semimembranosus
Tibial part of sciatic nerve
Posterior thigh muscles are more commonly known as
Hamstrings
What muscle has a hamstring portion
Adductor Magnus
What is a hamstring strain
Excessive stretch or tearing of muscle fibres in hamstrings, often seen in sports injuries (running and kicking)
Likely consequence of hamstring strain
Rupture of surrounding blood vessels producing a haematoma, which is contained by overlying fascia lata
Treatment of hamstring strain
RICE
Rest, ice, compression and elevation
What’s an avulsion fracture
Fragment of bone breaks away from main body of bone
Cause of ischial tuberosity avulsion fracture
Sports requiring rapid contraction and relaxation of hamstrings (sprinting, football and hurdling)
What is an avulsion fracture of the ischial tuberosity
Hamstring tendons tear off piece of ischial tuberosity
Treatment of ischial tuberosity avulsion fracture
Difficult to heal. May require surgery
Grades of hamstring strains
Grade 1 - over stretching without tearing muscle
Grade 2 - partial tear
Grade 3 - severe/complete rupture (visible lump may be present)
