Week 3 COPY Flashcards
The acetabular labrum encircles the acetabulum, it deepens it providing a more secure fit for the femoral head. By what percentage does it increase the articulate contact area of the femoral head with the socket?
10% - explanation - so that more than 50% of the femoral head is in contact with the socket at any one time
What is the small depression in the femoral head called, and what attaches here?
Fovea capitis - liganentum teres (ligament of the femoral head) attaches here
What is the only intracapsular ligament in the hip joint?
Ligamentum teres
Name the three extracapsular ligaments in the hip joint
Iliofemoral Ischiofemoral Pubofemoral
Which of the hip joints ligaments is the strongest?
Iliofemoral
What is the function of the iliofemoral ligament?
To prevent hyperextension of the hip
Note - looks like an inverted Y
Which ligament acts to prevent hyper extension of the hip
Mainly the iliofemoral joint, the pubofemoral joint also contributes to this somewhat
What are the functions of a) the ischiofemoral ligament b) the pubofemoral ligament
a) prevents excessive medial rotation b) prevent excessive abduction and hyperextension
What structure bridges across the acetabular notch (inferior part of acetabulum) and forms a tunnel through which blood vessels enter the hip joint?
The transverse acetabular ligament
The ligaments of the hip joint are weaker posteriorly, how does the body compensate for this in terms of stability
The strong hamstrings are located posteriorly and thus pull the head of the head into the acetabulum
Give three factors which increase the stability of the hip joint
The cup shaped acetabulum/ The acetabular labrum/ The capsule/ The intracapsular ligament (ligamentum teres)/ The extracapsular ligaments /The muscles surrounding the hip joint
What nerve innervates the hip joint a) anteriorly b) posteriorly c) inferiorly
a) femoral nerve b) sciatic nerve c) obturator nerve
What arteries form the extracapsular ring of the femoral neck?
The medial femoral circumflex artery and lateral femoral circumflex artery which are both branches of the profunda (deep) femoris artery
What arteries are the major blood supply to the head of the femur in the adult?
Retinacular arteries - branches of the femoris profunda artery
What risk does an intracapsular fracture of the femoral neck carry in an adult and why?
Avascular necrosis of the bone because of the severing of the retinacular arteries Explanation - this wouldn’t be the case in a child because the artery of the ligamentum teres is still the major blood supply to the femoral head
State the nerve roots of the lumbar plexus and the corresponding nerves
Ilioinguinal - L1 Genitofemoral - L1, L2 Lateral femoral cutaneous - L2, L3 Obturator - L2, L3, L4 Femoral - L2, L3, L4
State the nerve roots and corresponding nerves of the sacral plexus
Superior gluteal - L4, L5, S1 Inferior gluteal - L5, S1, S2 Sciatic - L4, L5, S1, S2, S3 Posterior femoral cutaneous - S1, S2, S3
Name two structures that pass through the greater sciatic foramen
Superior gluteal neurovascular bundle (vein artery and nerve)/ Inferior gluteal neurovascular bundle/ Sciatic nerve/ Posterior femoral cutaneous nerve/ Nerve to quadrator femoris/ Nerve to obturator internus
Where do the following structures exist a) sacrospinous ligament b) sacrotuberous ligament
a) sacrum to ischial spine b) sacrum to ischial tuberosity
What two structures run through the lesser sciatic foramen?
Tendon and nerve to the obturator internus
What bony landmarks demarkate where the sciatic nerve leaves the hip and enters the thigh?
Leaves midway between the posterior superior iliac spine and the ischial thberosity via the greater sciatic foramen Then after going over it’s muscles it passes midway between the greater trochanter of the femur and the ischial tuberosity
There are two sites that are used for intramuscular injections in the hip to avoid injury to the sciatic nerve. These two sites are the dorsogluteal site and the ventrogluteal site. Which is used in adults and children over 7 and why
Dorsogluteal because it is further from neurovascular structures. It isn’t used in younger patients because it requires better patient compliance
What muscle are we trying to inject into At the bentrogluteal injection site?
Gluteus medius
The fascia lata encloses the thigh muscles and is the site of attachment for the intermuscular septae that separates the thigh into its three compartments - the anterior, medial and posterior compartments. The saphenous vein penetrates it. It is thickest laterally where it forms what?
The IT band
What is the iliotibial tract/band?
A thickening if the fascia lata on the lateral aspect of the thigh
Where does the IT band run from?
The Iliac crest to the lateral tibial condyle
State the origin, insertion and action of the tensor fascia latae
Origin - anterior superior iliac spine Insertion - IT band at upper 1/3 of thigh Action - stabilises the hip in extension. Also helps stabilises the Knee, and assist in abduction Also has a minor role in compressing the deep veins to improve venous return from the lower limbs
The gluteal muscles are divided into superficial and deep muscles. The superficial muscles act to abduct and extend the thigh The deep muscles act to laterally rotate and abduct the thigh. List the muscles that comprise each group
Superficial - gluteus maximus, medius, minimus and tensor fascia latae Deep - piriformis, Gemellus superior, obturator internus, gemellus inferior, obturator externus and quadratus femoris
What is the blood supply to the gluteal muscles?
Superior and inferior gluteal arteries
What is the nerve innervation of a) the gluteus maximus b) the gluteus minimus c) gluteus medius
a) inferior gluteal nerve b and c) superior gluteal nerve