2.2 Flashcards
Joints of pelvic region
Sacroiliac joint
Lumbosacral joint
Pubic symphysis
Hip joint
Acetabular rim
provides hollow bowl
Acetabular labrum
Adds depth and forms articular cartilage
Lunate surface: articular cartilage
Acetabular notch: bridged by transverse ligament
Acetabular fossa: non-articulating and filled with synovial fluid
Head of the femur
Covered with articular cartilage
Fovea - no cartilage, attachment for the ligament of the head of the femur
Hip joint capsule
Synovial joint with external fibrous layer that attaches anteriorly to the femur
Proximal: acetabular rim and transverse acetabular ligament
Distal: intertrochanteric line and greater tubercle
Synovial membrane is thin, can become inflamed, and reduces friction of the joint.
Fibrous ligaments of the hip joint
Iliofemoral (Y ligament of Bigalow)
- limits hip extension during standing
- prevents hyperextension
- “hanging on your Y’s”
- (pink)
Pubofemoral
- inferior thickening of joint capsule
- prevents excess abduction
- (green)
Ischiofemoral
- posterior thickening of joint capsule
- limits medial rotation
- (yellow)
Where do femoral fractures occur?
Femoral head
Femoral neck
Intertrochanteric line
Distal to trochanters
Avulsion fractures of the hip
Often occur where there are powerful muscle attachments
Arteries of the hip and thigh
External iliac
- femoral artery
- deep femoral artery
Internal iliac
- obturator artery
Femoral and deep femoral artery
Medial circumflex artery (posterior)
Lateral circumflex artery (anterior)
Retinacular arteries:
- arise from circumflex arteries
- travel in synovium
Obturator artery
Artery to the head of the femur
Transverse ligament of the head of the femur (slight contribution)
Avascular necrosis of femoral head
The retinacular arteries are often torn when the femoral head is fractured of the hip joint is dislocated.
Can cause osteonecrosis of the femoral head
Retinacular arteries from medial circumflex femoral supply neck and head of femur
Which hip fracture would necessitate a total hip replacement because of likely avascular necrosis?
A
Hilton Law
The nerve supplying muscles that cross a joint also supply the joint
Anterior: femoral n.
Posterior: nerve to quadratus femoris
Inferior: obturator n.
Superior: superior gluteal n.
Adductor canal
Space deep to sartorius muscle
Contents:
- femoral artery and vein
- saphenous nerve
- nerve to vastus medialis
Adductor canal ends at adductor hiatus
- allows passage of femoral artery and vein to popliteal fossa from canal
Compartments of the thigh
divided by intermuscular septae, which are continuous with fascia lata
Muscles of the anterior compartment
Hip flexors and knee extenders
Most innervation by femoral nerve
Muscle:
- Quadriceps femoris
- Sartorious
- Pectineus
- Iliopsoas
Sartorius
Tailor’s muscle - “criss cross”
2 joint muscle: hip and knee joints
O: ASIS
I: superior medial tibia
A: flex, abduct, extension, hip rotation, knee flexion
N: femoral (L2, L3)
Iliopsoas
2 muscles with 1 common tendon
- Iliacus: O - iliac crest
- Psoas major: O - T12-L5
I: lesser trochanter
A: strong hip flexor, bilateral trunk flexion
N: Iliacus - femoral n; psoas - L1-L3
Causes lateral rotation by pulling lesser trochanter anteriorly
Quadriceps muscles
4 muscle bellies, 1 common tendon
Muscles:
- rectus femoris: O - AIIS
- vastus lateralis: O - femur
- vastus medialis: O - femur
- vastus intermedius: O - anterior and lateral shaft of femur
I: tibial tuberosity
A: knee extension
N: femoral n (L2-L4)
Knee jerk reflex
Myotatic reflex, deep tendon reflex
Tests integrity of femoral n and L2-L4
Tapping patellar ligament excites muscle spindles located in quad muscles, which causes a monosynaptic reflex to stimulate contraction of quadriceps femoris, normally causing leg extension
Example of myotome
Pectineus
Transitional between anterior and medial compartments
O: superior pubic ramus
I: pectineal line (posterior femur)
A: hip adduction and flexion
N: femoral n, sometimes obturator (L2-L3)
Muscles of medial compartment
Extends from antero-inferior pelvis to linea aspera
Mostly innervated by obturator nerve
Muscles:
- adductor longus
- adductor brevis
- adductor magnus
- gracilis
- obturator externus
Adductor longus and brevis
Parallel triangular muscles
Longus:
O - body of pubis inferior to pubic crest
I - linea aspera
Brevis:
O - body and inferior pubic ramus
I - pectineal line and linea aspera
A - thigh adduction
N - obturator n. (L2-L4)
- splits into anterior and posterior divisions
Adductor magnus
Largest and most powerful adductor
Most posterior
Adductor part: (purple)
O - inferior pubic ramus, ramus of ischium
I - gluteal tuberosity, linea aspera, medial supracondylar line
N - obturator n
Hamstring part: (green)
O - ischial tuberosity
I - adductor tubercle of femur
N - tibial division of sciatic n.
A - adduction, thigh flexion
Gracilis and obturator externus
Obturator externus: (purple)
- medial most muscle
- distal tendon is part of pes anserinus
O - obturator foramen and membrane
I - trochanteric fossa of femur
A - hip extension and rotation, steadies pelvis
Gracilis: (green
- deep
O - body and inferior ramus of pubis
I - superior part of medial tibial surface
A - hip adduction and internal rotation, knee flexion
N - obturator n.
Pes anserinus
Term for common tendon for:
- sartorius
- gracilis
- semitendinosus
Tendon attaches medially to tibial tuberosity
Mnemonic for innervation: SGT FOT
Sartorius - Femoral n
Gracilis - Obturator n
semiTendinous - Tibial .
