Session 7 Flashcards
What structures strengthen and deepen the acetabulum?
Acetabular labrum is a fibrocartilaginous rim that deepens the acetabulum. The transverse acetabulum ligament strengthens the inferior portion of the acetabulum, where the acetabular notch is.
What are the Extracapsular ligaments of the hip?
Iliofemoral - located anteriorly. It joins the ilium, immediately inferior to the AIIC, to the intertrochanteric line in two places, giving a Y appearance. It prevents hyperextension, body’s strongest ligament.
Pubofemoral - located anteriorly and inferiorly. Joins the superior rami of the pubis to the intertrochanteric line. Prevents excessive abduction and extension.
Ischiofemoral - located Posteriorly. Connects ischium to the femoral neck. Prevents hyperextension.
What is the intracapsular ligament of the hip?
Ligament of head of femur - runs from acetabular fossa to head of femur. It encloses a branch of the obturator artery, contributing to the hip joint blood.
What muscles produce what movements of the hip joint?
Flexion - Iliopsoas, sartorius and rectus femoris
Extension - gluteus maximus and hamstrings
Abduction - gluteus medius, gluteus minimus, tensor fascia lata and deep gluteals
Adduction - adductors longus, brevis and Magnus, pectineus, obturator externus and Gracilis
Lateral rotation - deep gluteals and gluteus maximus
Medial rotation - gluteus medius, gluteus minimus (anterior parts) and tensor fascia lata
What are the articulations of the hip joint?
Head of femur and acetabulum of pelvis
What nerves innervate the hip?
Femoral nerve, obturator nerve, superior gluteal nerve and nerve to quadratus femoris
What arteries supply the hip joint?
Medial and lateral circumflex femoral arteries from the profunda femoris artery (major) and obturator artery via ligament of head of femur (minor).
How does a fracture of the femoral neck most commonly occur in under 40s?
High energy collisions with the lower limb extended
Outline the procedure of a surgical hip replacement
A plastic socket is cemented to the hip bone to replace the acetabulum and a metal prosthesis replaces the femoral head and neck.
What is congenital dislocation of the hip joint and what are the symptoms?
More common in girls. The femoral head is not placed within the acetabulum during development, resulting in a dislocated joint. Symptoms include inability to abduct the hip, affected limb in shorter, positive Trendelenburg sign. Predisposes patient to arthritis later in life.
How can acquired dislocations of the hip occur and what are the two types?
They are quite rare due to the stable structure of the hip but can occur in traumatic accidents.
Posterior dislocations are more common where the head is forced posteriorly, tearing through the weakest part of the joint capsule. Common in car accidents when the hip is flexed, addicted and medially rotated. The affected limb becomes shortened and medially rotated and the sciatic nerve may be damaged (paralysis of hamstrings and all muscles distal to knee).
Anterior dislocations are more rare and is a consequence of forced extension, lateral rotation and abduction. The femoral head ends up anterior and inferior.
What results in the Trendelenburg sign and what is seen?
Superior gluteal nerve damage. Pelvic drop occurs on the unsupported leg when standing on one leg (look at the levels of the iliac crests). For example if the left gluteal muscles are weak, the right side of the pelvis will drop when the patient stands on their left leg.
What is the Q angle and what are the names of the conditions where this angle is abnormal?
Angle between femur and tibia. When angle is too big = genu valgum (knees inwards). When angle is too small = genu varum
What does the patellar tendon reflex test?
Femoral nerve and L2 - L4 spinal nerve segments
What are the borders of the adductor canal?
Anterior - sartorius
Lateral - vastus medialis
Posterior - adductor longus and adductor Magnus
Extends from apex of femoral triangle to adductor hiatus
