Exam 1: Lecture 5 - Surgery of the Hip II Flashcards
what are the procedures we can do to treat CHD
- triple pelvic osteotomy (TPO) or double pelvic osteotomy (DPO)
- femoral head and neck excision (FHO)
- total hip replacement (THR)
- juvenile pubic symphysiodesis (JPS)
what if the difference between a TPO and a DPO
in a DPO there is NO ischial cut
what procedure is shown in the picture
triple pelvic osteotomy (TPO) and stabilization with a bone plate
what procedure was done in this radiograph
femoral head and neck excision (FHO) femoral neck
what procedure are these implants used for and are the cemented or cementless
total hip replacement (THR)
what procedure are these implants used for and are the cemented or cementless
THR and cementless
What are these implants used for
THR (called kyon THR)
what procedure was done in these rads
THR
what is a juvenile pubic symphysiodesis
where you expose pubic symphysis with ventral midline incision over pubis
what procedure is this
juvenile pubic symphysiodesis
what is a coxofemoral or hip luxation
traumatic displacement of femoral head from acetabulum
what condition is seen is this animal
coxofemoral luxation or hip luxation
T/F: Coxofemoral luxation typically results in craniodorsal displacement of femoral head from acetabulum
true
what is usually the cause of hip lux in a craniodorsal displacement
trauma (specifically HBC)
T/F: Ventrocaudal displacements are more common than craniodorsal displacements in hip lux
false! Ventrocaudal is LESS frequent
what are ventrocaudal displacement hip lux usually associated with
femoral head may lodge within obturator foramen due to fx of greater trochanter
T/F: The amount of soft tissue damage with a hip lux surrounding the hip depends the type of trauma
true!!!
what ligament ALWAYS FAILS COMPLETELY during a hip lux
round ligament of femoral head
what causes the round ligament of femoral head to fail
due to an interstitial rupture or avulsion of ligament from fovea capitis
what happens to the fibrous joint capsule during coxofemoral/hip lux
the joint capsule is completely torn
T/F: you should always treat hip lux asap
true!
why should we treat hip lux asap
prevents continued damage of soft tissue surrounding the hip joint and degeneration of articular cartilage
early reduction of hip lux = return of ______ source for articular cartilage
nutrient
where does the articular cartilage get nutrients and how
from the synovial fluid…..it is pumped into matrix during normal articular movement
T/F: up to half of patients with a hip lux have a major injury in addition to the lux
TRUE!! hip lux is usually associated with trauma
what should we always do prior to treating hip lux and why
a PE prior to induction of anesthesia to ID concurrent trauma!
what is wrong with this dog (note how the paw and stifle are positioned)
craniodorsal hip lux
what is the “thumb test”
putting the thumb in space caudal to greater trochanter and externally rotate femur
what is A and B showing with the thumb test
the coxofemoral joint is intact so the greater trochanter displaces thumb
what is C and D showing with the thumb test
coxofemoral joint is luxated so greater trochanter rolls over thumb
how do we diagnose coxofemoral lux
by the position of greater trochanter related to ilial crest and tuber ischii
what is this picture showing
how we diagnose hip lux and the angles/what we feel for
what should we do prior to picking the best treatment for hip lux
radiographs should be carefully evaluated for avulsion of fovea capitis, associated hip joint fx, or degenerative changes secondary to CHD
what is the prognosis for spontaneous lux secondary to hip dysplasia
poor prognosis
what are the differential diagnoses for hip lux
- acute sublux or lux of hip joint secondary to CHD
- femoral capital physeal fx
- femoral neck fx
- acetabular fx
how do we medically manage a hip lux
with closed reduction which is attempting to replace the femoral head within the acetabulum
review: What is open reduction and closed reduction?
open - open surgical manipulation
closed - no surgical approach
T/F: We attempt a closed reduction for a hip kux prior to open reduction in most animals
true! Unless the rads have evidence of hip dysplasia or fx
T/F: patients do not have to be anesthetized for closed reduction
FALSE, they do
explain the steps of closed reduction of a craniodorsal lux
- grasp limb near tarsus with one hand and place other hand under limb against body wall to provide resistance
- externally rotate limb and pull caudally (but make sure femoral head is positioned over acetabulum)
- when femoral head is lateral to acetabulum internally rotate limb to seat femoral head in acetabulum
what procedure is being shown here
closed hip reduction
what should we do once the hip is reduced during a closed hip reduction and why
apply firm pressure to greater trochanter with vigorous range of motion of hip to help displace soft tissues and reduces the hematoma formation in acetabulum
how do we asses hip reduction
- palpation of landmarks (ilial crest, tuber ischii, greater trochanter)
- measure width of space between great trochanter and tuber ischii
- restoration of limb length
- comparison to contralateral hip
what is an ehmer sling
used to prevent pelvic limb weight bearing post hip reduction or acetabular fxs
what is this
ehmer sling
what are the steps of closed reduction of caudoventral hip lux
- place patient in lateral recumbency and hold limb perpendicular to spin
- grasp limb near tarsal joint with one hand and use other to stabilize body
- place traction on limb while simultaneously ABDucting leg to pull femoral head beyond medial rim of acetabulum
- once femoral head clears acetabular rim, apply lateral pressure medial to hip joint, push proximally and allow femoral head to fall into acetabulum
what do we do for the patient after a closed reduction of caudoventral lux
place in hobbles at tarsus or stifle for about 7 days
what is happening here
hobbles were placed on patient after a closed reduction of caudoventral lux
when do we do capsular reconstruction for hip lux
if the joint capsule is salvageable (but this is RARE)
what are the ways we can reconstructively fix a hip lux
- synthetic capsular reconstruction with suture and bone screws or suture anchor
- toggle pin placement
- additional stability is gained by translocation of greater trochanter
what can be a consequence of surgery to fix a hip lux
excess traction may lead to sciatic neuropraxia (minor injury that temporarily gives paralysis)
what are the requirements to use reconstruction of the joint capsule as the SOLE means of stabilization
- dorsal joint capsule is identifiable
- normal conformation of the hip
what is capsulorrhaphy
interrupted sutures to appose joint capsule
what is this
capsulorrhaphy
what is this a picture of
stabilization of hip lux via placement of a prosthetic capsule
how do we place a prosthetic capsule for hip lux
- placement of bone screws in dorsolateral acetabulum
- suture passed from screws through pre-drilled tunnel in dorsal femoral neck and then tightened
what type of stabilization of hip lux is this
toggle pin / toggle-rod fixation
how do we do a toggle pin / toggle-rod fixation
- drill hole centered through femoral neck and acetabular fossa
- attach multiple strands of nonabsorbable suture to toggle pin (use k-wire and toggle rod)
- pass toggle pin/rod thru hole in acetabular fossa and pull to set pin/bar
- pass sutures thru hole drilled in femoral neck and reduce hip and secure sutures
how do we stabilize hip lux via translocating the greater trochanter
- prepare site distal and slightly caudal to normal anatomic position
- stabilize greater trochanter in position with small pin and ortho wire (tension band)
what is this a picture of
tension band wiring
what is the post op care for hip lux
- ehmer sling to assist hip reduction early in postop period but removed around 4-7 days
- when ehmer sling is removed, begin controlled PT
- cage confinement adequate for dogs with stable hips
what is the prognosis/success rate of closed reduction to maintain reduction and good to excellent limb function
about 50%
when is there a poor prognosis of a hip lux
patient with poor conformation of the hip joint secondary to CHD or previous trauma
T/F: There is no difference in success of sx after a failed closed reduction
true
T/F: You should ALWAYS attempt a closed reduction in patients with hip lux
true!! Always try first
what is the prognosis/success rate of open reduction in maintaining the reduction with good to excellent limb function
about 85% to 90%
T/F: results don’t favor any one reconstruction technique for a hip lux
true!!
Review: what is legg-perthes disease
noninflammatory aseptic necrosis of femoral head occurring in young patients before closure of capital femoral physis
how do we manage legg-perthes disease
FHO or THR
what disease is shown in the rads and what was the procedure to fix it
legg-perthes disease and THR
