71. arthroscopy Flashcards
how are arthroscopes described
- diameter (1.9, 2.3, 2.7)2. length (short 8 cm, long 12.5 cm)3. lens angle (0, 30, 70 degrees)
bending of the athroscopic shows up as how on the field of view
black crescent at the periphery of the field of view or migration of the arthroscopic image across the monitor screen
advantage of high definition cameras
more pixel lines per screensharper image
3 chip camera
- zoom2. white balance3. image captureusually clip on, but also direct coupling systems
what resolution setting is recommended for arthroscopy
high horizontal resolution
light sources for arthroscopy
- Halogen–more yellow color2. Xenon–MOST COMMON, increased light intensity and higher color temperature with greater visual clarity and color rendition
T/F fiberoptic light cables heat up significantly and should NOT be placed directly against the patient
TRUEmay cause thermal injury if too close to the patient
benefits and optimal irrigation pressure for arthroscopy
- increases field of vision2. removes debris3. distends/expands jointSaline or LRS (no diff but LRS may be more physiologic)60 mm Hgdelivered with gravity flow or fluid pump (better when using shaver)
a 30 degree arthroscope allows for the equivalent of how many degrees of view
60 degrees
how to obtain a higher flow rate with gravity fluid pumping
–increase diameter of tubing–elevation of the bad 8-9 feet –using a pressure bag–3-5 L bags– Y adapters
T/Fflexion of a distended joint will increase intraarticular pressure
TRUE
what is the major advantage of working through a cannula
ease of instrument insertion
what is the most common reason for failing to locate the appropriate instrument portal site
entering the skin at too oblique of an angle and crossing over the arthroscopeor having the arthroscope too close
Where is the typical location of the scope portal for stifle arthroscopy
SCOPE portal LATERALLY (parapatellar)INSTRUMENT portal MEDIALLY (parapatellar)egress is advanced under the patellar tendon
the absence of articular carriage at the center of the trochlear notch is indicative of what
NORMAL–frequent finding in normal joints
According to Jardel VCOT 2010 what is the approximate relationship btwn a typical arthroscopic portal, instrument portal, and egress portal to pertinent neuro vascular structures on the medial elbow
SCOPE: 23.1 mm caudal to brachial artery, 21 mm caudal to median nerve, 4 mm cranial to ulnar nerveINSTRUMENT: 16.3 mm caudal to brachial artery ,13.5 mm caudal to median nerve, 12 mm cranial to ulnar nerveEGRESS: 21.4 mm caudal to ulnar nerve
according to Werner VCOT 2009 what is the SN and SP of arthroscopy for estimating RUI in dogs
SN 98%SP 89%
what is triangulation
instrumentation of the joint such that the instrument and the scope angle together to form the apex of a triangle
indications of shoulder arthroscopy
–OC/OCD fragment removal and/or debridement–disease of biceps brachia tendon–assess OA–synovial bx —synovial culture and lavage
lateral shoulder arthroscopy portals for OCD
- camera portal: craniodistal to acromion2. instrument portal: caudally in triangulation with scope 2 cm caudal to acromion3. egress: directed craniocaudal and medially at the level of the greater tubercleaxillary artery and nerve caudallysuprascapular artery and nerve cranially
lateral shoulder arthroscopy portals for biceps brachii tendon
- camera portal: craniodistal to acromion further caudal than with OCD lesion2. instrument portal: cranially in triangulation with scope 2 cm cranial to acromion can be medial to biceps brachia3. egress: caudally to acromionaxillary artery and nerve caudallysuprascapular artery and nerve cranially
surgical anatomy to view in shoulder arthroscopy
MCL (medial glenohumeral lig Y)Subscapularis tendonbiceps brachii tendon (has normal labrum or fibrous cuff)Glenoidsupraglenoid tuberclehumeral headcaudal joint pouchjoint capsule
medial elbow joint portals
camera: distocaudal to medial epicondyleegress: palpate olecranon process and insert needle on the medial side of process instrument: cranially to triangulate with scopeulnar nerve btwn egress and cameramedian artery and nerve cranially
hip arthroscopic portals
camera: perpendicular to limb just dorsal to greater trochanteregress: right hip 3 o’clock to greater trochanter 5 o’clock if left hipcaution ischiatic/sciatic nerve and caudal gluteal artery caudallyvisualize: round ligament, femoral head, acetabulum/acetabular labrum, transacetabular ligament
