muscle/tendon Flashcards
what is partial foot amputation
amputation of 2 consecutive digits
what is involved with central digit amputation for recon?
middiaphyseal osteotomy of metacarpal/tarsal bones and movement of distal m2 or m5 directly under 3rd/4th -> secure with plates
what are 2 additional foot recon techniques?
phalangeal fillet; full skin graft
what is recurrence rate of infiltrative lipoma
36%
for liposarcoma, what is factor associated with survival time? what are MST?
type of excision -
marginal 649 days
wide 1188 days
what are 1 yr survival rates SCC subungual vs other locations on digits
subungual - 95%
other areas - 60%
what breed is overrepresented with digital malignant melanoma? what is mst with vaccine + sx ?
Scotties, 351 d( with mets, without - longer)
List differential diagnosis for neoplasms of joint
synovial cell sarcoma, synovial myxoma, histiocytic sarcoma
for histiocytic sarcoma, what breeds predominate?
rotties, bernes mountain
for synovial myxoma, what breed predominate?
doberman
for muscular hemangiosarcoma, what is MST and how does it compare with sq HSA?
IM 272 d
SQ 1189 d
what is met rate and MST (sx alone) for chondrosarcoma ?
met 28%; MST 979 d in one study
for cats with OSA, what % is extraskeletal?
and of the skeletal what % is appendicular?
38%
55%
met rate for feline OSA?
10%
axial or appendicular feline OSA worse prognosis?
axial ( recurrence rate of 44%)
what are 3 main complications of limb spare sx? and their complication rates
infection (40-75%), local recurrence (25%), implant failure (30-40%)
what is prognosis and outcome for limb spare of proximal humerus?
poor; complication rate is high
what are MST with sx + chemo in OSA
amp alone - 20wks
amp + chemo - 290- 425 d
what are 2 modifications of vascularized ulnar transposition
- lateral manus translation
- microvascular transfer ipsilateral distal ulna
what are 2 modifications of bone transport osteogenesis? limb use at follow up?
- double bone transport osteogenesis
- transverse bone transport osteogenesis
- excellent
what is complication rate for irradiated autograft technique?
69% *nice
for limb spare surgery, ideally <__% radius to be involved for consideration
<50%
what is major disadvantage of cortical allograft for limb spare?
high infection rate (~50%) - forms sequestrum
also needs bone bank
what are the 2 main endoprosthesis
Kuntz - 3/6 L SS bar with flared end.
Biomedtrix tantalum implant (bacteriophobic, can drill screw in)
for Kuntz, what modifications have been made to decrease complications?
- remove portion of rod to decrease weight
- locking screws
- coat with hydroxyapatite
Explain types of hemipelvectomy
- total - entire; pubic symphysis to SI joint
- mid to caudal - pubic symphysis to ilium just cranial to acetabulum
- mid to cranial - SI joint to just caudal to acetabulum
-caudal - pubic symphysis to just caudal to acetabulum (allows for limb preservation)
What are some variations in technique to standard approaches
- if can’t preserve sartorius - do paramedian pubectomy to utilize medial muscles
-partial sacrectomy (<1/3 before loss of function)
Explain the difference between partial scapulectomy, subtotal scapulecomty
partial:
- preserves acromion process, acromial head of deltoids, and preserves distal infraspinatus/supraspinatus
subtotal:
- removes most of scapula (as far distal to notch)
- preserves glenoid and shoulder joint
what are good candidate criteria for scapulectomty to treat OSA?
- no soft tissue involvement
- removed with 2-3 cm margins distal to neosplasm
- shoulder preserved
any risk factors/prognostic indicators for this procedure (scapulectomy)?
- just increased body weight
- ____SA with decreased limb use???
- amount of scapula removed not associated
what % of OSA cases see gross mets at time of diagnosis?
15%
what are bone met rates and what are LN met rate for OSA?
27%; 4.4%
what bloodwork value associated with poor prognosis?
increased ALP
what are proposed causative factors for OSA after implants?
- chronic inflammation/infection
- corrosion of implants
- delayed healing
- decreased vascularity of bone post fracture
what % primary bone tumors are OSA?
what are some factors associated with increased risk?
85%;
increased height/weight, increased adolescent weight, increased circumference of radius/ulna, early OHE/castration?
what are the 2 peaks of OSA?
18-24 mos; 10yr
what are 2 most common sites of OSA?
(which have best/worst prognosis)
distal radius (best prognosis); proximal humerus (proximal humerus)
accuracy of bone biopsy is ___% for IO OSA
80-90%
treatment for hemimelia if <4-6 months?
sometimes bandage applicable (splint for radiocarpal for example)
what are treatment options for hemimelia at >4-6 and function unacceptable?
-conservative with splint/orthosis, wheel cart
-declawing select digits
-reconstruction (e.g. carpal arthrodesis)
-amputation
-fusion of defect and carpal arthrodesis with rib graft (autogenous)
what is demelia?
congenital duplication of whole or part of limb
what is ectrodactyly? what location usually?
split-hand deformity, lobster claw, cleft hand
- congenital digital cleft extending between metacarpal bones (most often thoracic paws - most in 1st and 2nd metacarpals)
Ectrodactyly is what species trait? what one?
cats - autosomal dominant
treatment options for ectrodactyly?
conservative (splint)
sx - amp or reconstruction (graft, etc)
what breeds commonly get polydactyly? what trait in inheritance?
St. Bernards and collies - autosomal recessive
in cats and most other dogs, what types inheritance is polydactyly?
autosomal dominant
explain classifications of syndactyly
- simple - interconnection between digits only skin/fibrous tissue +/- paw pads
- complex - soft tissue and bones fused
- complete - digits connected throughout length (P1-3)
- incomplete - digits connected partial length
what are other names for hypertrophic osteodystrophy?
- metaphyseal osteopathy, skeletal scurvy, juvenile scurvy, infantile scurvy, Moller Barlow’s disease, osteodystrophy
breeds commonly seen with HOD? what of those has high heritability
Great Dane, Chesapeake, Irish Setters, Boxers, GSD, Goldens, Labs, WEIMARANERS
causes of HOD?
Vit C deficiency
overnutrition
heritability
inflammation
vaccinations
infections
treatment/prognosis?
often self limiting (support (if severe): steroids, IVF, analgesics, antacids);
prognosis good to excellent if mild; guarded if severe - can recur
what is panosteitis
self-limiting inflammatory disease of bone marrow that leads to vascular congestion and increased intraosseous pressure
(AKA enostosis, eosinophilic panostietis, shifting leg lameness)
panosteitis signalment?
most common bone?
treatment?
risk factors?
- 5-12 months, males> females (4:1), dogs >23 kg, large breeds, NW/north central region US
- ulnar - 42%
- rest and analgesics; benzopyrone
- breed, age, weight, sex, season (summer to fall)
what breeds most often seen with cranio-mandibular osteopathy? age risk?
westies, scotties, cairns
<6 months
which bone is most affected by cranio-mandibular osteopathy?
treatment?
prognosis?
- mandible +/- tympanic bullae
- +/- self limiting 11-13 months (regress); supportive care; surgery -excision or bilateral rostral mandibulectomy (salvage)
- fair to good (IDK), but euthanasia if cant eat or painful
what is multiple cartilaginous exostoses?
theory for development?
what is it associated with in felines?
- benign disease - cartilage capped bony protuberances surfaces of any bone
- via endochondral ossification originating from growth plate chondrocytes displacing outside growth plate
- feline leukemia virus
other names for cartilaginous exostoses?
multiple exostoses, diaphyseal aclasis, chondroma, dyschondromplasia, osteochondromatosis, multiple osteochondromata
treatment for multiple cartilaginous exostoses
analgesics;
surgery to remove if need to restore function, prevent neoplastic transformation, constant pain, improve cosmesis
Treatment and prognosis for Swimmers syndrome
hobbles and PT; good if done within 1-3 weeks of birth
with Puppy Laxity Syndrome, what are the types and what angles? treatments? prognosis?
- hypoflexion >30 degrees, hypoextension <180 degrees (but digits extended), hyperextension >190 degrees
- conservative - exercise, splint, and change diet; sx for severe - tenotomy of affected tendons, +/- pancarpal arthrodesis
- good to excellent
list metabolic bone disease
primary hyperparathyroidism:
- nutrition/ secondary (renal) hyperparathyroidism
- hypo vit D
- hyper vit D
- hypo vit A
- hyper vit A
- hypo vit E
what are causes of hypovit D
- poor nutrition
- lack of sunlight
- defective metabolism of vit D
- inherited vit D receptor defect
- hypo PTH
- CRF
- renal loss P
- malabsorptive states
with hypertrophic osteopathy, where is it occurring
distal extremities and long bones; bilateral symmetric or all 4 limbs
theory of hypertrophic osteopathy occurrence? treatment?
increased peripheral blood flow and congestion of periosteum (irritation of afferent nerves from primary process? + vagal, intercostal, nervous reflex)
treatment of the primary problem (mass resection) and metastatectomy (can still recur)
what is disseminated idiopathic skeletal hyperostosis?
spinal and extraspinal manifestation of heavy bone formation
what breed predisposed and what part of spine most often affected by disseminated idiopathic skeletal hyperostosis?
ventral logintudinal ligament; boxers
what are the criteria to diagnose?
-continuous flowing calcification >3 contiguous vertebra -preserves IVD width and no degenerative disc disease
-periarticular osteophytes on ZPJ
-pseudoarthrosis between spinous processes
-periarticular osteophytes and calcification ST attachments
what are other names of bone cyst? what breed seem commonly affected?
osteitis fibrosa cystica, polyostotic fibrous dysplasia, brodie’s abscess
dobermans (polyostotic )
other names for acute caudal myopathy? breeds seen with the disease? treatment?
limber tail, rudder tail, sprain tail, frozen tail, cold water tail
pointers and labradors
NSAIDs -> recovers within 1-2 weeks
what is the gait pattern for iliopsoas muscle injury?
short PL stride; pain on hip extension
what PE test can you do to id pain? treatment?
***maneuever test - hip flexed, internally rotate and extend the limb OR palpate ventromedial to the ilium
what is the gait pattern, PE findings with infraspinatous muscle contracture?
- circumduction of limb with advancement +/- carpal ***
- shoulder abducted, elbow adducted, lower limb abducted and externally rotated
what is the gait and PE findings with quadriceps contracture?
- atrophy, limb held straight (or hip flexed ) with both stifle and tarsocrural joint extended (+/- bear weight on dorsal pes)
what is the gait for gracilis muscle contracture?
limb raised jerk-like fashion with hyperflexion of tarsocrural joint and internal rotation of metatarsus
what is the treatment for gracilis and semintendinosus contracture?
conservative - recurrence is high
treatment for flexor carpi ulnaris contracture?
decrease activity with support bandage for 2 weeks
if no success, transection tendon FCU
patients with what disease have higher incidence of myositis ossificans?
von Willebran disease
what is the difference between healing of paratenon versus sheathed tendons?
paratenon - when damaged, receive vascular buds and influx of undifferentiated cells from paratenon and surrounding soft tissue structures
i.e - gastrocnemius and triceps
sheathed - depend on intrinsic blood supply
i.e. - DDF
how long does suture need to hold for tendon healing
first 3 weeks
tendon has ___% original strength at 6 weeks
___% original strength at 1 year
56%; 79%
normal muscle contraction strain tendons at ___% capacity?
25-33% (so can exercise slowly after 6 weeks)
locking loop and krackow _____ technique?
these patterns are good for which tendons
grab bundles
good for flat tendons
3 loop pulley -> resistance to ____?
this pattern is good for which tendons?
pull-outs
round tendons
what is a common mistake people make with repairing deep digital flexor tendon ruptures?
fail to ID DDF and repair SDF , leading to weight bearing on metatarsal pad
what is prognosis for digital flexor repair?
good
what is prognosis for long digital extensor repair?
good
what is amelia?
congenital absence of 1 or more limb
thoracic limb - mono or abrachia
pelvic limb - mono or apodia
breed predisposition for amelia?
what is hemimelia
beagles
complete or partial absence of one or more bones
list four descriptive types of hemimelia
terminal - if all or some absent distal to certain point
Intercalary hemimelia - bones proximal and distal to the missing bone or bones are present.
transverse - complete absent bone across limb width
longitudinal - absence one or more bones along the long axis (medial or lateral) of limb
how long does dynamic correction last for dynamic ulnar osteotomies?
2-4 weeks
what is the proposed max age for distal osteotomy/ostectomy to allow translation?
which (distal/prox) gives greatest movement in adults?
4-6 months
adults - proximal (4.7) versus distal (<1)
For DDUO - how much to remove and where?
4-5 mm; 2-3 cm proximal to distal ulnar epiphysis
For using partial carpal arthrodesis, what can’t be damaged?
antebrachiocarpal joint
For pancarpal arthrodesis - what is ideal angle for extension?
10-12 degrees
for dorsal approach arthrodesis, what tendons need transection?
extensor carpal radialis (II/III)
list plate options for pancarpal arthrodesis?
DCP
hybrid DCP (VOI)
LC-DCP
single or double stepped hybrid (Insurvet)
castless plate
what is complication rate of arthrodesis?
7-50%
list complications of arthrodesis
how do we decrease complications?
screw loosen, implant breakage, infection, metacarpal bone fracture, implant sensitivity, incomplete arthrodesis, gait abnormalities
screws on metacarpal bone <40% bone diameter
plate spans >50% length of metacarpal 3
For ulnar ostectomy, what are ways to prevent premature healing of gap?
creation of ostectomy gap > 1.5 x diameter of bone
insert fat graft
remove all periosteum near ostectomy
don’t hit radius (to decrease risk of synostosis)
what breed gets accessory carpal bone fracture most?
Greyhounds (50% of reported)
what are the 5 types of accessory carpal bone fracture?
frequency reported? which are intra-articular?
1: an intraarticular distal basilar fracture resulting in the avulsion of the origin of the accessorioulnare ligament - 67%
2: an intraarticular proximal basilar avulsion fracture - 13%
3: a distal apical fracture resulting in the avulsion of the origin of the accessoriometacarpeum ligament - 3%
4: a proximal apical avulsion fracture of the flexor carpi ulnaris muscle - 12%
5: comminuted fractures - 5%
list the 7 theorized mechanisms of types of incongruity in development of MCP disease
1 - closed radius of curvature of ulnar trochlear notch relative to humeral condyle
2 - radioulnar incongruity - static (linear vs angular)
3 - dynamic RU incongruity - depend on deformation of RU cup with weight bearing
4 - localized RU incongruity at apex of MCP
5 - pressure within RU joint (rotational RUI)
6 - varus - instability of H-R-U joint: both compress MCP between humeral trochlea and radial head
7 - dynamic axial HU joint instability
6,7 - both compress MCP between humeral and trochlea and radial head
Describe scores for International Elbow Working group
0 - Normal
1 - mild: osteophytes < 2mm, subtrochlear sclerosis, can see trabeculae
2 - moderate: osteophytes 2-5 mm, subtrochlear sclerosis, RU step 3-5 mm, no traveculae
3 - severe: osteophytes > 5mm, RU step > 5, can see primary lesion
what are range of sensitivity/specificity for identifying RU incongruity on rads?
Sensitivity - 75-100%.
Specificity - 42-90%
for CT, what % can be false negatives for detecting cartilaginous lesions?
one study showed 29% (confirmed via scope)
what are the 4 types/patterns of MCP shapes as seen on CT?
Type 1: rounded
Type 2: pointed
Type 3: flattened
Type 4: irregular
Where does the joint capsule of elbow contain the supratrochlear foramen?
cranially
normal ROM for flexion of elbow? extension?
36 degrees flexion
165 degrees extension
In extension, anconeus is the primary stabilizer in ____.
Lateral collateral is primary stabilizer in ____.
pronation (in extension)
supination (LCL)
With elbow flexion, what is the primary stabilizer for rotation?
medial collateral ligament
list all conservative management strategies for treatment of elbow disease (MCP)
- NSAID and rest
- IA steroids, HA or PRP
- IA stem cells
- acupuncture
- joint denervation
- nonselective denervation joint cavity
- PMMA subchondral injection
- radiation therapy
what % UAP cases are bilateral? sex predilection?
20-35%
male > females (2:1)
what % UAP cases have FCP? RU incongruity?
13-30%
RUI 50-100%
what makes (+) vs (-) incongruence?
(+) - long ulnar (short radius)
(-) - radius overrides ulnar at distal ulnar notch
when does ossification of anconeal process occur?
14 weeks
what % of shoulder OCD cases trap within tendon sheath of biceps brachii?
10%
give advantages of:
- caudal approach
- caudolateral approach (how is this different)
- craniolateral approach
- caudal approach: easier fragment removal
- caudolateral approach (how is this different): retraction of infra/TM(?); craniodorsal protects circumflex humeral artery/axillary nerve
- craniolateral approach via tenotomy of infraspinatous: greater exposure
give disadvantages of:
- caudal approach
- caudolateral approach (hpw is this different)
- craniolateral approach
- caudal approach: less visibility
- caudolateral approach:
- craniolateral approach: less ability to remove fragments
prognosis of shoulder OCD
excellent
what situations should you not use radiofrequency induced thermal modification (RITM) in shoulder?
complete medial G-H ligament tear
bilateral disease
acute conditions
other TL orthopedic/neuro disease
moderate or severe shoulder joint OA
lack of owner compliance
what are prognosis rates for:
RITM
BB tendon transposition
arthrodesis
BB transposition - good to excellent 84.5%
Arthrodesis - good to excellent 85.7%
RITM - excellent - 79%, 93% improvement
anconeal process prevents luxation until elbow flexed at ____.
45%
what does it imply with lateral elbow luxation? (what has to occur)
both collateral are ruptured
what % of elbow luxations have anconeal process still in olecranon fossa?
16%
transection of MCL increase pronation to ____.
transection of LCL increases supination to ____.
MCL - 60-100 degrees (normal is 30 degrees)
LCL - 70-140 degrees (normal is 46 degrees average)
For RU incongruency evaluation with CT, what is the current protocol?
duplicated circle superimposition technique
3 D rendering of RU joint has what sensitivity and specificity for identifying RUI?
sensitivity 86%
specificity 77%
in using scope to detect RUI, what do you use? sensitivity/specificity?
right angle probe - 1.9 mm scope
limit manipulation of joint and 135-145 degrees
sensitivity 94-98 %; specificity 81-89%
what % of scapular fracture are articular? what type is most common?
28%
58% are cranial glenoid (including Supraglenoid tubercle)
list 4 ways to repair scapular neck fracture
- cross pins (1 cr, 1 dorsal)
- divergent pins (both cr)
- plate
- T plate
what are 2 approaches to fracture of articular region?
osteotomy of greater tubercle (+ insertion of supraspinatus) OR longitudinal myotomy of supraspinatus
list 2 ways to repair fracture of Supraglenoid tubercle?
screw (lag fashion) with antirotation wire, 2 k wires + TB***
list synthetic materials for bone graft substitutes
Ceramics
CaPO4 ceramic - duplicating hydroxyapatite
Coralline bone graft substitutes (Coral - CaCO3)
Tricalcium PO4
Biphasic CaPO4 (hydroxyapaptite + tricalcium PO4)
Nanocrystalline CaPO4
Calcium sulfate (plaster of Paris)
Hydrogels (3D polymer)
Describe 2 main classifications of nonunion and their subcategories
viable:
- hypertrophic: ‘elephant foot”; too much movement
- oligotrophic: no rad evidence of activity (lack of cell activity)
nonviable:
- dystrophic: nonviable on 1 or both sides
- necrotic: infected section (sequestrum)
- defect: gap at fracture site (can see resorptive/sclerosis at margins)
- atrophic: narrowing/candlestick
when scar tissue forms with muscle injury, tension decreases to ___ of original capacity
50%
early mobilization after ___days to encourage aligned myofibrils
5-10 d
what breed do we see often rupture long head of triceps
greyhounds
what breeds are often seen for gracilis muscle injury
greyhounds racing; GSD; foxhounds
treatment options for avulsion fracture of CdCLR?
- bone screw
- wire structure formed from loop cerclage placed through bone tunnels
- divergent K wires through fragment exiting far cortex of femoral condyle
- wire suture formed from loop of cerclage wire
what are treatment options of midsubstance tears of CdCLR?
- joint capsule imbrication and suture around part of PL to drill hole in proximal tibia(med and lateral)
+/-strip of fascia sutured fibular head to augment lateral suture
+/- desmodesis MCL or tenodesis long digital extensor or popliteal tendon
+/- imbricate fascial lata
with luxation and subluxation of proximal intertarsal due to plantar instability, what is treatment of choice?
arthrodesis calcaneoquartal via transfixation pain and TB or single compression screw from calcaneus to 4th tarsal bone (w or w/o TB wire or plate)
what breeds seen with above condition (luxation and subluxation of proximal intertarsal due to plantar instability)?
middle aged, overweight shelties/collies
what breeds see external metatarsal rotation? what is it associated with and what is the treatment? prognosis?
-Bernese mt dogs
-anomalies of central tarsal bone
-correct rotational deformity and arthrodesis of proximal intertarsal joint
-excellent
what is different for cat tarsal ligaments versus dogs?
only have short collaterals
at the level of the tarsocrural joint, what is the main artery called
dorsal pedal
what are the 3 nerves supplying distal hindlimbs
tibial n - medial and lateral plantar nerve
common peroneal n - superficial and deep peroneal nerve
femoral n - saphenous - dorsomedial tarsus/metatarsus
which carpal bones articulate with IMR (intermedioradial) carpal bone?
C1,2,3
carpal bone 4 articulates with which metacarpal?
MC IV and V
what don’t the carpal ligaments cross
all 3 joints of carpus
how does accessory carpal bone attach to the carpus?
MC IV and V via accessory metacarpal ligaments
4th and ulnar carpal bone separate ligaments
where are flexor retinaculum and palmar fibrocartilage attached?
flexor retinaculum - medial part of accessory carpal bone to medial styloid process and distal to IMR and 1st carpal
palmar fibrocartilage - all proximal carpal except accessory, C1-4, and proximal MC 3-4
what are the historical surgical guidelines to repair metacarpal fractures primarily?
- if > 2 MC or MT fracture in same manus
- fracture involve both primary weight bearing digits (3/4)
- articular
- displaced by > 50%
- involves base of metacarpal and metatarsal 2 or 5
large breed/athlete/working dog
what are the 3 types of metacarpal fracture injuries in greyhounds. what is the prognosis for each?
Type 1: endosteal and cortical bone thick and patient lame
Type 2: minimally displaced hairline -> splint 6-8 weeks
Type 3: complete fracture with complete displacement, then surgery
Types 1/2 - good.
Type 3 - guarded
what are variations in joint angles of antebrachiocarpal joint in dog?
42.5 - 52.4 degrees
how do cats and dogs differ in paw placement at stance?
cats - pronate front at beginning until paw in neutral position
dogs - put all 4 weight bearing phalanges on ground at same time
with carpus, which ligament has highest elastic modules? lowest? function of each?
accessorometacarpal ligament - highest; prevent hyperextension
MCL/LCL - lowest; support varus/valgus
function of palmar radiocarpal and ulnocarpal ligaments
restrict craniocaudal instability (are intra-articular)
for pancarpal arthrodesis,
Bristow vet sx 2015 reported rad healing ____% with hybrid DCP vs ____% with castless
hybrid DCP - 40%
castless - 46.2%
which type of plates typically used for partial carpal arthrodesis?
T plate; castless
what is another option to treat via arthrodesis that isn’t plate
pins - M3/4 then cross pin M2 to ulnar carpal bone with M5 to IMRC bone
what part of metacarpal bone is the head?
distal
where are the epiphysis in metacarpals and when do they ossify
M1 - proximal
M2-5 - distal
ossify at 5-6 months
what does the interosseous metacarpal ligament do?
attaches distal MC to each other
joint capsule and extensor tendons unite ____ joint dorsally.
proximal interphalangeal
what is Q-angle?
deviation of direction of forces of quadriceps
what is average Q-angle?
10.5 degrees
list treatment options for MPL
trochlear sulcoplasty - ‘abrasion trochleoplasty’
trochlear chondroplasty
trochlear wedge recession
trochlear block recession
tibial tuberosity transposition
retinacular release
capsulotomy
imbrication
quadiceps fascial release
fasciectomy
distal femoral osteotomy
For femurs, dogs can compensate femoral length discrepancy <____%
20
what are predisposing fractures described to contribute to quadriceps contracture
skeletally immature
exuberant bony callus
extended coaptation
muscular trauma
infection
extensive ST manipulation
describe vascular anatomy to proximal femur
extraosseous:
- lateral and medial circumflex femoral (forms vascular ring)
- cranial/caudal gluteal iliolumbar
Intracapsular:
- forms from extracapsular ring which penetrates joint capsule, travels cranial dorsal neck and form intracapsular ring. then penetrate physis to form intraosseous
intraosseous:
- formed from intracapsular ring and branches of caudal gluteal and medial circumflex femoral
which species DOES receive artery of ligament of head of femur?
cat
describe the fracture locations of proximal femur (intra vs extra capsular)
intracapsular - epiphyseal, physeal, subcapital, transcervical
extracapsular - basilar neck, intertrochanteric, subtrochanteric
what is reported inclination angle?
130-145 degrees
what is reported normal anteversion angle?
27-32 degrees
what are early rad signs of hip dysplasia? what age?
7 weeks - FH subluxation and underdeveloped acetabulum
what are factors proposed to influence development of hip dysplasia?
genetics (GSD,BMD)
joint laxity (>0.3)
increased synovial fluid production
muscle mass disparity
estrogen and relaxin
heavier weight
decreased Vit Ca and Ca++
pectineal muscle myopathy
excess feeding
most common breed for hip dysplasia?
GSD
Rottweilers
Lab
Golden
St Bernard
Large breeds
what are the 3 defined components of LCL?
when are they taut
long lateral - tight on extension
calcaneofibular short - tight on extension
talofibular - tight on flexion
of 3 above, which is main component of LCL?
calcaneofibular
give the names and attachment of the plantar ligaments in tarsus
middle plantar (‘long’ in Miller’s) - base calcaneus to 4th tarsal and MT 4&5
medial plantar (calcaneocentral) - sustenaculum tali to central tarsal then tarsometatarsal joint capsule
calcaneoquartal (‘lateral’) - lateral and caudal calcaneus to MT5 (with the long collateral)
what lies within the tarsal canal? where is it located?
-tendon of flexor hallucis longus
-plantar branch of saphenous a/v and medial/lateral plantar muscle
- medial to calcaneus and plantar to talus
describe the medial collateral ligament components in the tarsus. for the MCL, which is taut when?
long ligament:
- medial malleolus to 1st tarsal, central tarsal, talus, and T2
- taut on extension and loose on flexion
short ligament:
- tibiocentral - taut on extension, loose on flexion
- tibiotalar - taut on flexion and loose on extension
which part of MCL is most substantial component?
tibiotalar
what % of musculoskeletal cases are muscle disorders?
5%
when muscle strained to 80% of failure, strength of contraction decreased by ___% right after injury
_____% 24 hrs, ____% 48 hours
BUT recovery to ___% (5 of normal function) after 1 week
Right away - 30%
24 hrs - 50%
48 hrs - 25%
Return to 90% in 1 week
which muscle are subject to strain?
BB, triceps, pectorals, serratus ventralis, rhomboideus, extensor carpi radialis, flexor carpi ulnaris
what is the difference in diagnostic tests to classify ‘probable’ vs ‘definitive’ SLE?
Probable:
- ANA (antinuclear antibody) >160, 1 major sign, +/- minor
- ANA <160, 2 or more major (except IMHA, IMPA)
Definitive:
- 2 or more major signs, ANA >160, 1 major and greater or equal to 2 minor
prognosis for SLE?
guarded
Degradation of aggrecans in articular cartilage - incited by what?
matrix metalloproteinases- 13 (MMP13)
for synovial fluid analysis, what is normal total cell, % mononuclear, % neutrophils?
Normal:
Total cell - < 2x10^9/L
% mono - 94-100
% neut - 0-6
for synovial fluid, what is total cell, % mononuclear, % neutrophils for OA and infective arthritis?
OA:
Total cell - 2 - 5 x10^9/L
% mono - 88-100
% neut - 0-12
Infective arthritis:
Total cell - 40 - 267 x10^9/L
% mono - 1-10
% neut - 90-100
what is osteochondrodysplasia? treatment?
bone/cartilage disease - abnormal endochondral and/or intramembranous ossification
ie dwarfism
symptomatic treatment - cause not addressable
what is dysostoses?
what are 3 underlying causes?
abnormal development of individual bones or parts of bones
- failure of bone model to form
- failure of model to transform to cartilage
- failure to convert from cartilage to bone
name 3 types of muscle injuries
contusions (blunt), strains (indirect), laceration
what are 3 stages of muscle injury
Stage 1 - myositis, bruising but architecture intact
Stage 2 - myositis and some tearing of fascial sheath
Stage 3 - tearing of fascial sheath, muscle fiber disruption, and hematoma formation
what muscles are more likely to get stage 1/2? stage 3?
1/2 - triceps, biceps femoris, quad, tensor fascia lata, semimem/semitendi
3 - long head of triceps, gracilis, gastrocnemius, tensor fascia lata
what is the pathophysiology of slipped capital femoral epiphysis? theory?
either growth plate separation from multicentric physeal dysplasia
OR
delayed closure of physeal growth plate due to gonadectomy and hypotestosteronism and obesity and increase exposure to shear forces
what feline breeds are commonly affected by slipped capital femoral epiphysis? what % are bilateral? prognosis?
siamese
24-38%
excellent
what are other names for Legg-Calve-Perthese disease? Breeds most affected? what percent are bilateral?
avascular necrosis of femoral head
aseptic necrosis of femoral head
osteochondritis coxae juvenilis
coxa plana
osteochondrosis
toy breeds, terriers, mini poodles and westies
12-16.5%
prognosis with conservative versus sx treatment?
Medial (rest and NSAIDs) - resolution < 25%
Sx - 84-100% resolution
List limb sparing surgical techniques of R/U
cortical allograft
endoprosthesis
pasteurized autograft
vascularized ulnar transposition
bone transport osteogenesis
irradiated autograft
stereotactic radiosurgery
partial amp and endoprostehsis
ulnectomy
intercalary limb spare
Describe the 2 different sacral fracture classification scheme
Kuntz:
abaxial - lateral to foramina or fracture of spinous process
axial - medial to foramina, ventral to spinous process
Anderson:
1 - alar
2 - foraminal
3 - transverse
4 - avulsion
5 - commonuted
what % of sacral fractures cases have neuro deficits
~ 69% (noice)
what plate angle options are available for TPO/DPO?
TPO: 20,30,40
DPO: 25, 30
DPO ventroversion of acetabular usually ____degrees less than TPO
5 degrees
what degree of acetabular rotation is desire?
____ degrees greater than than what?
want 5 degrees more than measured angle of subluxation (increase additional 5 degrees for DPO)
don’t go above what degrees of ventroversion? why?
don’t go over 40 degrees.
can worsen pelvic canal narrowing
impingement of dorsal acetabular rim on neck
what size makes metallic grains stronger? what are 2 ways to make smaller?
smaller - foraging vs investment casting
greater the elastic modulus mismatch the greater
risk of wear debris or stress shielding
describe biomechanical properties of:
- cobalt alloy
- SS 316L
- titanium alloy
- tantalum
- cobalt alloy:chromium, nickel, molybdenum; excellent wear resistance, hard, corrosion resistance
- SS 316L: Fe, chromium, nickel, molybdenum; corrosion resistance
- titanium alloy: biocompatible, alloy strong and good fatigue resistance, but more wear debris (> cobalt-chromium)
- tantalum: metal with porosity; elastic modulus similar to cancellous bone
explain adhesive, abrasive, fatigue, corrosion, and erosive wear
adhesive:
- soft bearing surface to opposite surface
- cold weld and breaks from original surface
abrasive:
- irregularity on hard surface leads to damage to opposing side
- creates 3rd-body wear
fatigue:
- cycle loading surface to surface microcracks
- creates surface delamination
erosive:
- solid particle (impact on surface) OR
impingement - implant to implant versus implant to bone with range of motion
corrosive:
- oxidation from interaction of dissimilar materials
