TBL 15/16 application of knowledge Flashcards
What are avulsion fractures of the hip bone?
a small bone with a piece of a tendon or ligmanet attached is avulsed; occurs at apophyses (bony projections that lack secondary ossifcation centers) where muscle attach -> anterior superior and inferior iliac spines, ischial tuberosities, and ischiopubic rami
How can twisting of the flexed knee create the unhappy triad injury?
caused by blow to the lateral side of the extended knee or excessive lateral twisting of the flexed knee that disrupts the TCL and concomitantly tears and/or detaches the medial meniscus; ACL is taut during flexion and can also tear -> “unhappy triad”
What are the anterior and posterior drawer signs?
anterior = free tibia slides anteriorly under the fixed femur; posterior = free tibia to slide posteriorly under the fixed femur
What causes Osgood-Schlatter disease and what are its symptoms?
disruption of the epiphysial plate at the tibial tuberosity -> cause inflammation of the tuberosity and chronic recurring pain during adolescence
Where is the gracilis muscle used for transplantation and why is lower limb function not noticeably compromised?
it is a relatively weak member of the adductor group of muscles so it can be removed without noticeable loss of its actions on the leg; used to replace a damaged muscle in the hand or for a non-functional external anal sphincter
What lesions might cause diminution or loss of the patellar tendon reflex?
results from any lesion that interrupts the innervation of the quadriceps (i.e. peripheral nerve disease); reflex tests the integrity of the femoral nerve and the L2-L4 spinal cord segments
Why can aseptic vascular necrosis of the displaced femoral head occur after femoral neck fractures?
femoral neck fractures often disrupt the blood supply of the head of the femur -> artery to the ligament of the femoral head is only source of blood but it is inadequate
What are compartment syndromes and how are prolonged symptoms relieved?
fascial compartments of the lower limbs are generally closed spaces; trauma can produce hemorrhage, edema, and inflammation of the muscles -> increased intracompartmental pressure that compresses structures like small vessels, leading to ischemia and viability of tissue within; prolonged symptoms are relieved by a fasciotomy (incision) to relieve the pressure in the compartment
Why is the common peroneal nerve frequently injured and what are the symptoms after its injury?
because of its superficial position as it winds subcutaneously around the fibular neck, leaving it vulnerable to direct trauma; severance results in flaccid paralysis of all muscles in the anterior and lateral compartments of the leg (dorsiflexors of ankle and evertors of the foot) -> makes the limb “too long” so the toe do not clear the ground during the swing phase of walking
Where is the dorsal pedis pulse palpated and what is the most common cause of its diminution or absence?
palpated with the feet slightly dorsiflexed, just lateral of the EHL tendons; most common cause of its diminution or absence is vascular insufficiency resulting from arterial disease
When is a saphenous cutdown required and where can sensory loss occur after the procedure?
in trauma or hypovolemic shock patients when peripheral cannulation is impossible; saphenous nerve can be cut -> pain or numbness along the medial border of the foot
How is caudal epidural anesthesia performed and which spinal nerves are typically affected?
inject local anesthetic agent into the fat of the sacral canal that surrounds the proximal portions of the sacral nerves -> acts on the S2-Co1 spinal nerves of the cauda equina, controlled by the amount injection and position of the patient; can be done by injecting through the sacral hiatus or posterior sacral foramina
How do the gluteus medius and minimus, and the piriformis and quadratus femoris contribute to the stance and swing phases of walking?
swing phase: gluteus medius and gluteus minimus normally contract to prevent tipping of the pelvis to the unsupported side; piriformis and quadratus femoris synergize to laterally rotate the thigh
What are the main lesions that cause a positive Trendelenburg test?
injury to the superior gluteal nerve; patient asked to stand on one leg, the pelvis on the unsupported side descends indicating that the gluteus medius and minimus on the supported side are weak or non-functional -> positive Trendelenburg test
Where is the safe area for intragluteal injections?
safe only in the superolateral quadrant of the buttocks or a line extending from the PSIS to the superior border of the greater trochanter (approximating the superior border of the gluteus maximus)
