Lecture 18 - Muscles of the pelvic girdle and thigh Flashcards
Abdominal aorta branches
Abdominal aorta splits to left and right common iliac
common iliac spliets into internal and external iliac artery
external iliac artery turns into the femoral artery once it passes through the inguinal ligament and this goes all the way to the foot
deep femoral artery (profunda femoris)
Femoral triangle
Inverted triangle, a transition area from pelvis into thigh
Boundaries • Superior (base): inguinal ligament • Medial: adductor longus • Lateral: sartorius • Contents (from medial to lateral) – VAN
Blood supply to the hip and the thigh
External iliac to femoral artery (after passing under the inguinal ligament)
Main blood supply to thigh muscles = Deep femoral artery and vein
It has perforating branches wrapping around the femur
Femoral artery is a common location for catheterization
Blood vessel supply to the thigh
Femoral artery passes through the adductor hiatus (in adductor magnus), and becomes the popliteal artery
Adductor magnus
for thigh adduction
where does the popliteal artery come from
femoral artery foes to the posterior side through the adductor hiatus and becomes the popliteal artery
Popliteal artery is in the
popliteal fossa (posterior)
Boundaries of the popliteal fossa
Semimembranosus
Semitendinosus
Biceps femoris
Gastrocnemius
Content - behind the knee
Popliteal vein (V) Popliteal artery (A) Tibial nerve (N) Common fibular nerve
Lower limb innervation
Forms three main peripheral nerves • Sciatic (tibial and common fibular) • Femoral • Obturator Plus gluteal nerves
Femoral nerve course and supplies..
Course:
• Emerge between psoas major and iliacus (iliopsoas)
• Passes from the pelvis into the anterior thigh under the
inguinal ligament
• Runs through femoral triangle with the femoral artery and femoral vein
supplies anterior thigh and skin (anterior thigh and medial leg)
femoral nerve innervates
Muscles in the anterior thigh
Skin in anterior thigh & medial leg
Main functions of femoral nerve
The main functions of anterior muscles are hip flexion & knee extension
Femoral nerve injury leads to
Femoral nerve injury leads to weakness/difficulty in hip flexion and/or knee extension (brings femur up)
Posterior muscles that attach to the hip and knee cause
hip extension and knee flexion
Anterior muscles that attach to the hip and knee cause
hip flexion and knee extension
Obturator nerve
Exits the pelvis into the medial thigh through the obturator foramen
Innervates muscles in the medial compartment of the thigh
The main function of these muscles is hip adduction
Supplies medial thigh muscle for hip adduction
Sciatic nerve
Enter the posterior thigh through the
greater sciatic foramen
If sciatic nerve pierces through the piriformis muscle, the person may have piriformis syndrome
supplies posterior thigh, leg and foot muscles
Superior gluteal nerve
goes above piriformis muscle and supplies hip abductors
Main function of hip abductors:
• To maintain a level pelvis during single leg stance
• Hip abduction and internal rotation
Superior gluteal nerve injury leads to dropping of contralateral pelvis
Inferior gluteal nerve
below piriformis and supplies the gluteus maximus
The main function of this muscle is hip extension
Inferior gluteal nerve injury causes:
• Not much impact on walking
• Difficulty in getting up from a chair or climbing stairs
Superior gluteal nerve injury leads to
dropping of contralateral pelvis
Inferior gluteal nerve injury causes:
- Not much impact on walking
* Difficulty in getting up from a chair or climbing stairs
Iliopsoas is a
hip flexor
Hip flexors list
Iliopsoas
Quadriceps femoris (incl rectus femoris)
Sartorius
Iliopsoas origin
- Iliacus: Iliac fossa and crest
* Psoas: vertebrae
Iliopsoas insertion
Lesser trochanter (common attachment of iliopsoas at the lesser trochanter)
Iliopsoas functions
Strong hip flexor (contraction brings about hip flexion)
Flexes trunk if legs fixed
Iliopsoas nerve
Femoral
Parts of quadriceps femoris
- Rectus femoris
- Vastus medialis
- Vastus intermedius
- Vastus lateralis
Rectus femoris movement =
hip flexion as it is the only muscle from quadriceps femoris that crosses the hip
knee joint extension and quadriceps femoris
- Vastus medialis
- Vastus intermedius
- Vastus lateralis
Common attachment of the four heads of quadriceps femoris =
quadriceps tendon (tibial tuberosity)
Rectus femoris origin
Origin: Anterior inferior iliac spine
Rectus femoris insertion
Quadriceps femoris tendon –> patella –> patellar ligament –> tibial tuberosity
Rectus femoris function
- Hip joint: flexes
* Knee joint: extends
Nerve of rectus femoris
Femoral nerve
Origin of sartorius
Anterior superior iliac spine
Insertion of sartorius
Medial side tibia (pes anserinus)
Sartorius functions
Known as the Tailor’s muscle
(sitting cross-legged)
Hip: flexes, abducts, externally rotates
Knee: flexes
Cross leg = hip joint flexion, abduction, lateral rotation and flexion at the knee
Sartorius nerve innervation by
Femoral nerve
Pes anserinus
Insertion site for three muscles (one from each compartment of the thigh) • Sartorius • Gracilis • Semitendinosus
Say Grace before Tea
pes anserinus acronym
- Sartorius
- Gracilis
- semiTendinosus
Hip extensors list
Gluteus maximus
Hamstrings
Gluteus maximus origin
Posterior ilium, lateral sacrum and coccyx
Gluteus maximus insertion
Gluteal tuberosity
Iliotibial band
Gluteus maximus functions
Hip extension (for standing up because posterior)
For climbing steps
for changing from sitting to standing position
Nerve and blood for gluteus maximus
Inferior gluteal
Hamstrings location
posterior thigh
Three muscles of hamstrings
- Semitendinosus
- Semimembranosus
- Biceps femoris (has a long and a short head)
Hamstrings origin
- Ischial tuberosity
- Except biceps femoris short head: linea aspera (shaft of femur) - long head of biceps femoris attachs to ischial tuberosity
Hamstring insertion
Tibia – semimembranosus and semitendinosus
(not at the same location!)
Head of fibula – Bicep femoris
Function of the hamstrings
Actions:
• Hip: extends
• Knee: flexes
• Rotation at the knee (lateral rotation by bicep femoris, medial rotation by semitendinosus and semimembranosus)
Nerve of the hamstrings
All are supplied by tibial nerve, except for
short head of bicep femoris
Hamstring injuries
May happen in sports requiring sudden acceleration or decelerations such as sprinting or kicking in balls.
Hip abductors
Gluteus medius and minimus- Medius is on top of minimus
Tensor fascia lata
Gluteus medius and minimus origin
Ilium
Gluteus medius and minimus insertion
Greater trochanter
Tensor fascia lata origin
Origin: ASIS & Iliac crest
Tensor fascia lata insertion
Insertion: Iliotibial band
(thickening of deep fascia of thigh)
IT band also attached to gluteus maximus so pulls on it when you try stand up from sitting
Function of hip abductors
Hip joint abduction and internal rotation
Maintain pelvis horizontal during single-leg stance
In case of muscle weakness or nerve injury: dropping of contralateral pelvis (Trendelenburg sign/gait)
Nerve and artery of hip abductors
Superior gluteal
Hip adductors
Three “adductors”
(brevis, longus (part of femoral triangle), magnus (adductor hiatus))
Pectineus
Gracilis
Origin of hip adductors
except for adductor magnus
pubic bone
Insertion of hip adductors
except for adductor magnus
femur
Adductor magnus origin
Pubic bone and Ischium
Adductor magnus insertion
Femur and adductor tubercle
Adductor magnus - adductor hiatus
Adductor hiatus – passage of femoral artery into popliteal space.
Adductor magnus
Has adductor and hamstring parts
Functions of hip adductors
Functions: to adduct the thigh, but when do we adduct?
- Stabilize one-leg stance, together with the abductors
- Adductor magnus has a hamstring part for hip extension
Swing phase of gait
Adductor longus contributes
to hip flexion (e.g., kicking with medial side of the foot in soccer)
Hip adductors innverated by
Innervated by the obturator nerve
Enters the thigh through the obturator canal (foramen in
the obturator membrane)
