MSK Flashcards
joints affected by bog spavin
distal IT and TMT joints
aetiology of bog spavin
concussion and shear forces/stress on hock joints
- common in jumpers, western pleasure, STBs
- conformation predisposition
CS of bog spavin
- mild HL lameness, freq. bilateral
- reduce performance
- breaking on turns
rad signs of bone spavin
osteophytes + enthesiophytes + sclerosis + lysis + joint narrowing
bog spavin conservative tx
- corrective shoeing
- intra-articular corticosteroids +/- HA
- systemic NSAIDs, PSGAG, HA, Epitalis
sx tx of bog spavin
arthrodesis of distal hock joints
sites of OCD in the tarsus
- Distal intermediate ridge of the tibia
- Lateral trochlear ridge of talus
- Medial malleolus
- Medial trochlear ridge of talus
OCD of tarsus prognosis
good to excellent w/ athroscopic sx
ddx of capped hock
- gastrocnemius bursitis
- calcaneal bursitis
- DDFT sheath effusion
tx of capped hock
- stop inciting cause
- drain bursa + inject w/ corticosteroids
- topical and systemic AI + pressure bandage
define thoroughpin
= tenosynovitis of the tarsal sheath (flexor tendon sheath of DDFT)
CS of thoroughpin
- swelling lateral and medial to common calcaneal tendon and proximal to tuber calcis
- most are not lame
tx of thoroughpin
- drainage
- intra-tendinous corticosteroids and/or HA (acts as antiinflm + reduces adhesion to tendon sheath)
- often recurs
- tenoscopy and lavage + ABs if infected
what is curb?
soft tissue swelling of plantar aspect of tarsus
CS of curb
- convex appearance to plantar aspect calcaneous
- acute lameness w/ pain on palpation
US findings of curb
- desmitis of long plantar ligament
- tendonitis SDFT
OR inflam/thickening of soft tissue at back of tarsus
tx and px of curb
- Rest
- Topical and systemic AIs
- Inject area w/ corticosteroids (US guided)
- Freeze firing de-innervates the c-fibres which provide pain sensation in area
Mostly good px but can recur.
Guarded for STBs - tend to chronically re-injure area
tarsal fracture characteristics
- most are slab fxs
- Can be managed conservatively or Lag screw fixation w/ CT
- Prognosis fair/good but will develop OA in joint if conservative tx only
tx of tibial stress fxs
- stall rest for up to 6months
diagnosis of tibial stress fractures
- CS: mostly TBs in training, acute onset HL lameness w/ no other signs
- Blocks are inconclusive
- Rads - some changes if chronic
- Nuclear scintigraphy/bone scan = definitive diagnosis
CS of upward fixation of the patella
- Medial patella lig locks over medial femoral condyle –> HL locked in extension, toe drags
- Usu intermittent - may mimic stringhalt
- When they release the stifle often exaggerated flexion of the hock
- Typically worse in the morning - horse cold/not warmed up
Tx of upward fixation of the patella
- Exercise program: trot work and deep sand/hill work
- Oestrogen supplementation supposed to relax ligaments - wkly injection of oestradiol
- Counter- irritants over medial patella ligament
- Surgery: Medial patella desmoplasty - stab incision into medial patella ligament
Last resort = medial patella desmotomy
tx and px of cranial cruciate ligament rupture
- rest + AI
- guarded px
characteristic gait of fibrotic myopathy of the semitendinosus/semimembranosus muscles
foot rapidly snatch down during anterior phase
signalment of fibrotic myopathy
QH, polo, cutting, roping horses
–> tearing of flexor muscles
tx of acute fibrotic myopathy
AI, rest, physio, intra-lesional cortisone
causes of peroneus tertius rupture
- overextension of the hock
- direct trauma
- avulsion fractures in foals
dx of peroneus tertius rupture
simultaneous flexion of stifle and extension of hock
tx of peroneus tertius rupture
rest, AI (local + systemic NSAIDs) + controlled exercise program after 6wks
treatment of pelvic fxs
stall rest 4-6months + re-evaluate
tx of proximal femoral physis fracture in foals
internal fixation - lag screws/ 135 dynamic hip screw
treatment of craniodorsal coxofemoral luxation
- closed reduce under GA
- open reduction w/ joint imbrication, screw and wire fixation or translocation of greater trochanter
- femoral head ostectomy for <200kg
CS of sacroiliac subluxation
- reduced performance, lameness acutely
- muscle spasm and pain on palpation
tx of sacroiliac subluxation
inject w/ cortisone or counter-irritant + rest 3m
what CS is diagnostic for sacroiliac subluxation?
“hunter’s bump”
- asymmetry of rump either side of spine
what is high vs. low ringbone?
OA of interphalangeal joints
high = proximal IP jt
low = distal IP jt
what conformational faults predispose to ringbone?
- Toe-in or Toe-out: sloping coronet + jt imbalance
- Uneven wear on distal joints + hoof wall
- Offset pastern: abnormal breakover
- Abnormal stresses on lower joints
high ring bone blocks to..
abaxial sesamoid nerve block
management of ring bone
- Intra-articular medications
- corticosteroids
- HA
- IRAP (interleukin-1 receptor antagonist protein)
- Arthramid - Corrective shoeing: balance foot, roll the toe
- Pain meds: PSGAGs + NSAIDs (bute/melox)
sx tx of ring bone
- Pastern joint arthrodesis
fair prognosis HL> FL
treatment of palmar/plantar eminence fractures of P2
- lag screw fixation + cast
OR - arthrodesis
pastern subluxation causes disruption of what soft tissue structures?
- SDFT and collateral ligs
- distal sesamoid ligs
tx of pastern subluxation
pastern arthrodesis
arthrodesis technique for comminuted fxs OR palmar/plantar instability of pastern
= double plate fixation
indications for a transfixation cast
- severely comminuted fxs
- open fxs
treatment of pastern OCD
- intra-articular medication
- bute
- rest
–> will develop OA (if severe OA arthrodesis)
OR transcondylar screw across cyst
name the 6 different types of sesamoid fxs
- Apical
- Mid-body
- Basal
- Abaxial
- Sagittal
- Comminuted
why do proximal sesamoid fxs occur?
- high speed exercise + hyperextension of the fetlock
- trauma
Diagnosis of proximal sesamoid fx by rads. What else do you need to know for prognosis?
need to check for concurrent SL damage via ultrasound
which is the most common type of sesamoid fx?
apical sesamoid bone fx
what causes abaxial sesamoid fractures?
avulsion fractures at the SL insertion point in racehorses
why is surgery not indicated in abaxial sesamoid fxs?
could cause disruption of the suspensory lig
what forces cause mid-body sesamoid fractures?
the bone is pulled in two directions by the suspensory and the sesamoidean ligs –> bone fails
prognosis for basilar sesamoid fxs?
guarded - depends on fragment size
- loss of integrity w/ sesamoidean ligs
tx principles of sesamoid articular fxs
- remove fragments up to 1/3 size of bone
OR - lag screw larger fragments + cast
why are sesamoid fxs notoriously poor healers?
- poor blood supply
- tension
- movement
discuss prognosis for different types of sesamoid fxs
Good for apical + abaxial
Guarded for Basilar, midbody, axial + comminuted
rad findings assoc w/ sesamoiditis
increased size and number of vascular channels
two manifestations of fetlock OCD
- OCD of sagittal ridge of distal MC III
- subchondral cystic lesions of distal cannon bone
treatment of sagittal ridge lesions
- Type 1: no tx if incidental - allow horse to mature
2. Types II and III - arthroscopic removal
tx of cystic lesions in fetlock
- lag screw across cyst
- IA corticosteroids
common site of chip fractures of the fetlock joint
medial dorso-proximal eminence P1
why are HL P1 fxs more commonly spiral/larger fxs than FLs?
HL = greater torsion forces
P1 short complete fx tx
- stall rest if <10mm
- lag screw
lameness assoc. w/ P1 long incomplete fxs
4/5 grade lameness
tx of complete sagittal fxs of P1
- internal fixation w/ lag screws
difference between Type 1 and Type 2 proximal palmar/plantar P1 fragments
Type 1 = articular
Type 2 = non-articular
cause of palmar/planter OC disease of MC/MT III
- heavy/premature training of immature skeleton –> repetitive hyperextension = microfractures – cartilage damage –> bone necrosis + lysis
- common in 3-4yo TBs in training
- flattening of palmar condyle(s) of MC III –> impact pt during gallop
px of POD of MC/MT III
guarded in severe cases
prevention and rest is key
what’s a hygroma?
fluid filled swelling over the dorsal aspect of the carpus
hygroma ddx
synovial hernia
hygroma tx
- needle drainage
- inject corticosteroids 2-3x
- pressure bandage for >14days or will come back
common sites of carpal chip fractures
- distal lateral radius (RC joint)
- distal radiocarpal bone (MC jt)
- proximal C3 (MC jt)
why do carpal slab fractures most commonly occur in C3?
the biggest bone and susceptible to a lot of load
lameness assoc. w/ C3 slab fx?
grade 4-5/5 - hobble
C3 slab fractures are best seen with what rad view?
skyline of carpus
tx and px of accessory carpal bone fx
- support and stabilise carpus (splints + lots of bandage)
- rest for 4-6m
- fair to good prognosis
recommended physio of in tx carpal fxs?
flex carpus 20-30x daily to prevent fibrosis of the joint
prognosis of carpal fxs
- rel to amount of cartilage damage and OA present
- depends jt involved: radiocarpal > midcarpal
- gen. good to very good
what is third carpal bone disease?
starts w/ subchondral lysis as a respone to remodelling because of the load being placed on it then secondarily hardens –> sclerosis
Bone hardness prediposes to subchondral plate failure + chip/slab fxs
tx of third capal bone disease
- rest usu 6-12wks, up to 6m
- athroscope: can debride to encourage healing (but rare)
- IA and systemic chondroprotective agents IRAP, pentosan
px of third carpal bone disease
given lack of successful tx –> guarded to fair
likely outcomes for radial fxs
- euthanasia
- double plate internal fixation if <250kg
CS for ulnar fractures
- loss of tricep mm function
- dropped elbow
- swelling around joint
benefits of splint stabilisation for a non-displaced fx
- restores limb support
- prevents contracture
- protects contralateral limb
match the ulnar fx type w/ plate fixation method
- Type 1 + 2 = curved plate for apophyseal fxs
2. Types 3-6 = tension band plate
tx of olecranon bursitis
- NSAIDs
- needle drainage + intralesional corticosteroids
- surgical drainage OR en bloc resection
++ nullify inciting cause: soft/deep bedding or bell boots/pastern rings
two types of humeral fxs
- Acute severe trauma –> complete fx
2. Stress fxs –> incomplete
how does size effect humeral fx prognosis
- if <200kg: double plate fixation + IM interlocking nail + IM pins
- If >200kg - stall rest if incomplete or euthanasia if complete
CS of radial nerve paralysis
- unable to extend carpus or advance limb
- dropped elbow, drags limb, marked head movement
prognosis of scapular supraglenoid tubercle avulsion fracture
- if small articular component can remove
- lag screw and tension band wire
fair prognosis, OA may develop
prognosis of spine/body scapula fxs
- poor
- high risk of implant failure w/ such thin bone
what cause sweeny?
- should trauma
- stretch from caudal slippage of limb
- damage to brachial plexus
–> causes suprascapular nerve damage –> atrophy of infraspinatus and supraspinatus muscles
conservative vs. sx tx of sweeny?
- Stall rest for up to90d –> spont recovery
2. Surgery –> release nerve from entrapping fibrous tissue +/- conservative notching of scapula (fx risk)
classification of condylar fractures
- fx configuration: complete/incomplete
2. location: displaced/non-displaced, lateral/medial
Lateral condylar fractures tx options
- Prior to sx limb stabilisation + analgesia + IVFT
- Incomplete/non-displaced = lag screw fixation
- Complete = lag screw fixation +/- open reduction
tx of medial condylar fractures
- open reduction, lag scre fixation and neutral plate
- standing lag screw fixation via stab incisions
radiographic diagnosis of shin soreness
- periosteal new bone over dorsal cortex of MCIII
- thickened dorsal cortex
- radiolucent lines in dorsal cortex
- unicortical oblique fracture(s) in dorsal cortex = saucer fx
is high speed work okay for shin soreness?
yes - but shorter workouts + less often is req.
tx of shin soreness
Rest 60-90d
AI
+/- Freezing firing, Percutaneous periosteal scraping, ESWT
tx options for stress fxs
- Osteostixis
2. Unicortical screw
what is ‘splints’?
bony exostosis of the 2nd or 4th MC/MT bones
clinical significance of distal splint bone fxs?
- assess suspensory lig involvement via US
- often left and reform themselves
compare tx of proximal splint bone fxs on the medial vs. lateral splint bone
Medial splint bone - remove up to 1/3 prox + implants
Lateral splint bone is more forgiving –> conservative/internal fixation or complete removal
