Arthroscopy Flashcards
Why do portals need to be separated as widely as possible?
to avoid skin necrosis if portals are placed too close to each other
if an instrument falls or breaks within a joint, what should be done immediately?
outflow of saline should be shut down while the inflow is left open to keep the joint distended for retrieval of broken piece
what anatomical structures are considered when making an anterolateral portal?
btwn EDL and superficial peroneal n.
when is the transmalleolar approach for lesions of the talus contraindicated?
in children with open epiphysis
What anatomical structures are considered when making an anteromedial portal?
btwn TA tendon and saphenous vein
what is the most common size and angulation of an arthroscope used in an ankle?
2.7mm and 30 deg
or 0 deg of angulation
what is the min. distance an accessory portal should be placed btwn two working portals?
at least 1cm apart to avoid skin necrosis
in anterior soft tissue impingement of the ankle, pathology is generally limited to what areas?
syndesmosis and lateral gutter
when using a posterolateral approach, what structures should you watch out for?
sural nerve
saphenous vein
also avoid entering the STJ
transmalleolar portals are more often required on which side of the ankle joint and why?
on the medial side because lateral dome lesions are more anterior than on the medial side, and becuase the lateral malleolus is further posterior than the medial malleolus
what are 3 basic joint surveying techniques in ankle arthroscopy?
scanning
pistoning
rotating
prior to beginning arthroscopy, which portal is developed first?
the medial portal is developed first and the scope is placed in to survey teh joint prior to lateral portal development
what are the contraindications for manual distraction and/or gravity distraction?
tight ankles
pathology not easily accessible
prolonged procedures
what are the contraindications to the use of skeletal distraction?
local or generalized osteopenia
open epiphysis
lax ligaments
what are some indications for the use of single heavy pin distraction (3/16 inch)?
large bone structure in males
long cases or difficult pathology
very tight ankles
ankle arthrodesis
what are some advtgs of double pin (7/64) distraction?
better control
less stress riser than 3/16 inch
less chance of pin tract infection
when a 3/ 16.5 invasive distraction is used, how long post-operatively should the patient avoid athletic activity or heavy work?
8-10 wks to decrease the risk of fx
when 7/64.5 invasive distraction is used, when can the patient return to activity?
4-6 wks
what specific type of synovitis occurs in 3 stages?
chronic synovial chondromatosis
which disease entity is characterized by synovitis with advanced papillary formation and hemosiderin cells present?
pigmented nodular synovitis
what is used in drilling an OCD of the talar dome?
0.062 K wire
what is the MOI for a medial talar dome lesion?
plantarflexion and inversion
what is the MOI for a lateral talar dome lesion?
inversion of the foot with the ankle dorsiflexed and tibia internally rotated on the talus
how should a bone graft be placed in articular cartilage of teh talar dome?
1-2mm below the level of teh cartilage
what is one method that has been proven helpful in viewing chondral lesions of the ankle joint?
methylene blue dye injected into the joint and then washed out with irrigant saline
what technique is used in arthroscopic ankle arthrodesis?
arthroscopic transmalleolar cross-screw fusion
what are some advantages of arthroscopic approach to ankle fusion over the open method?
less surgical morbidity and improved cosmesis
wha tis a disadvantage of the arthroscopic approach to ankle fusion?
severe varus/valgus alignment is difficult to correct arthroscopically
what is a contraindication to doing arthroscopic ankle fusion?
varus/valgus malalignment > 15 deg
Name the arthroscopic technique that involves insertion of another object such as a probe beside a target structure into the field of view of the arthroscope in order for the physician to better conceptualize the relative positions of these objects relative to adjacent structures.
triangulation
according to R.W. Jackson (1982) is more relief of symptoms achieved with diagnostic arthroscopy attributable to joint lavage or lyses of adhesions?
joint lavage- 21%
lysis of adhesions- 4%
what is the classification system for talar dome lesions?
Berndt and hardy sTage 1- compression of articular cartilage Stage 2- an incompelte fx stage 3- non displaced complete fx stage 4- displaced complete fx
which side of the talar dome usually produces a shallow wafer-shaped fx?
anterior lateral
which side of the talar dome procedues deep, cup-shaped lesion?
posterior medial
what is the procedure for sterilization of a scope?
1st case- ethylene oxide gas
if additional cases- activated glutaraldehyde solution for 20 min
*arthroscopes cannot be autoclaved
what is the probable diagnosis if only 10-12 mL of saline can be injected into the ankle joint capsule of a normal sized adult?
capsular adhesions or fibrosis
plantarflexion of teh foot increases the visualization for which group of arhtroscopic portal approaches?
medial
dorsiflexion of the foot increases the visualization for which group of arhtroscopic portal approaches?
lateral
Name indications for ankle arthroscopy.
chronic ankle instability persistent ankle joint pain OCD anterior impingement exostosis ankle fx ankle fusions arthritis adhesive capsulitis synovitis meniscoid bodies chondromalacia,
describe pistoning.
movement of arthroscope towards or away from an object
*pistoning would increase object’s apparent size while decreasing total field of vision
describe scanning.
sweeping side to side or up/down to get a more complete view of the joint. the idea is to go from known to unknown areas of the joint to distinguish normal from pathological structures
describe rotation.
movement of arthroscope about its axis. the field of vision is changed depending on teh obliquity of the arthroscope tip. the larger the degree of tip cut, the wider the field.
what instrument has a sharp point and is used to pierce soft tissue and capsule?
trocar
what isntrument has a blunt end and is used to enter a joint?
obturator- used to prevent iatrogenic cartilaginous damage
what is used to distend the ankle joint and maintain a clear view of teh camera?
saline irrigation
for OCD, osteoarthritis, chondromalacia, burrs are used to abrade articular defects to what level?
viable bleeding bone
what structure is the landmark for locating the proper site for an anteromedial approach for ankle arthroscopy?
TA tendon (go medial to it)
an anterocentral portal is always located lateral to what structure?
EHL
what nerves are at risk for being injured with the anteromedial port?
saphenous n.
what nerves are at risk for being injured with the anterocentral port?
deep peroneal n
what nerves are at risk for being injured with the anterolateral port?
terminal branches of superficial peroneal n.
what nerves are at risk for being injured with the posteromedial port?
tibial n.
what nerves are at risk for being injured with the posterolateral port?
sural n.
what is teh purpose of a stopcock on the sidearm of teh cannula?
the ingress/egress of fluids
