Ch 61c Deranged Stifle Flashcards
Etiology, Pathogenesis, Pathophysiology, and Epidemiology
- multiple ligaments, and often the menisci, are damaged.
- Ligament injury classified as
- first-degree (minor overstretching, but fibers intact),
- second-degree (tearing of some fibers),
- third-degree (complete tearing or avulsion of the ligament, ligament nonfunctional).
- third-degree resulting in significant joint instability warrant surgical treatment.
- Meniscal injury and rupture of one or both of the cruciate ligaments should always be suspected in cases in which collateral ligament injury is severe
- Both medial and lateral collateral ligaments are taut in extension
- both limit internal tibial rotation.
- in flexion, the MCL is taut and prevent external tibial rotation.
- in flexion, lateral collateral ligament relaxes
Diagnosis
- traumatic event is typical > therefore assess all body for concurent injury
- Lameness can vary from mild to non–weight bearing
- varus stress test: assess lateral collateral, stifle joint held in extension, mild increase if isolated, Markes varus suggest concurrent cruciate rupture
- valgus stress test: assess medial collateral, in extension, mild valgus and marker extenal rotation isolated, marked valgus if conccurent cruciate
- Stress radiography
- neurovascular status of the distal limb should be carefully assessed in luxation
the exact combination of injuries remains presumptive until surgical exploration can be performed
stifle luxation
- Stifle joint luxation can vary in complexity of how many ligmanets inovlved
- secondary stabilizers damage: joint capsule, menisci, and possibly the patellar ligament
- ## complete stifle joint luxation, the vascular supply to the distal limb must be carefully evaluated because the popliteal vessels may become entrapped
treatment
- exploration of the joint is the first step
1. meniscotibial attachments, repair by suturing can be attempted
2. collateral ligament injury is present, it should be addressed next
3. stabilization of cruciate ligament instability
Temporary stabilization of the joint in a weight-bearing position of approximately 140 degrees of flexion can be accomplished with a transarticular Kirschner wire
Extra-Articular Stabilization
Second-degree injury
- treated with suture imbrication or conservative treatment.
Midsubstance tears:
- locking loop pattern anchored to a bone screw and washer
- repairs are often augmented with a protective transarticular suture connected to bone screws and washers,bone tunnels or bone anchors
- joint in extension because this mitigates the risk of iatrogenic shortening
Avulsions of the femoral or tibial attachments can be repaired
Transarticular Stabilization
Augmentation of a primary repair can be achieved with a variety of transarticular devices
- very small patients, intramedullary pins (140 degrees flexion, distal aspect of the tibial crest, through the intercondylar area of the tibia, and into the femur.), cast is placed for 5 to 7 weeks
- may result in permanent loss of range of motion.
- A hinged transarticular fixator, with at least three half pins in the femur and tibia, plane of motion and the axis of rotation of the hinge are parallel to those of the stifle joint, 6 to 8 weeks
- frame removal, joint stability and range of motion should be assessed; in addition, radiographs
Outcome, Prognosis, and Complications
- good function can be obtained with meticulous reconstruction or stabilization
complications
- Arthrofibrosis (30-40 degrees loss ROM)
- recurrent joint instability
- Rigid transarticular stabilization techniques can result in femoral or tibial shaft fracture
- hinged ESF effectively sustained joint motion, allowed early weight bearing, and preserved joint motion
STUDY: found no benefit derived from hinged, transarticular skeletal fixation over primary repair.
Traumatic stifle injury in 72 cats:
a multicentre retrospective study
Coppola 2022
Seventy-two cats. retrospective.
The most common combination involved both cruciate ligaments and the lateral collateral ligament (25.4%).
Medial meniscal injury was more common, 66% vs 59%)
Postoperative immobilisation (56.9%)
Short-term complications 40/64 (62.5%) cats.
Long-term complications occurred in seven
(17.5%) cats.
Revision surgery was performed in 23.9%
good to excellent in the majority of cats (62.3%)
TA seft post-op associated with more complications/poorer outcome
postoperative immobilisation had no positive effect on outcome and may not be required
cranial cruciate ligament, which was treated using a fabello-tibial suture in 58 cats, with nylon. Most cats the caudal cruciate not repaired
transarticular pin for temporary intraoperative joint stabilisation was used in 31.5%
A transarticular external skeletal
fixator was used in 33 cats
Complications
Intraoperative complications occurred in 8.2% (n = 6/73)
limb amputation in 5 cats (6%)
stifle reluxation 6 (8%)
MPL 3 cats
femur/tibia fractures 4 cats
long term: lameness, instability 5 cats
patients can take several months to recover fully.
ManageMent of seveRe
stifle tRauMa
Stifle luxation in cats - 2019
- Peripheral avulsions of menisci
can be reattached to the joint capsule using
horizontal mattress sutures of polydioxanone - A 1.6 mm Kirschner wire (K-wire) is placed as temporary intra-op
- fabellotibial sutures, fibulopatellar
sutures and/or prosthetic colatteral ligaments - collateral ligmanets: A 2.0 mm screw or a suture anchor, Size 0 monofilament non-absorbable, insertion point for the lateral collateral ligament is the fibular head.
- The peroneal
nerve (Figure 6) runs just caudal to the
fibular head, so care must be taken - A lateral fabellotibial suture is placed to
address rupture of the cranial cruciate ligament> 50 lb, a suture anchor can instead if concerns about fabella laxity - any residual drawer sign, then placement of a fibulopatellar suture is recommended, placed circumferentially around the fibular head, the proximal aspect of the patellar
ligament. - A type i lateral transarticular external skeletal fixator is used with 2.0 mm positive profile pins placed in the femur and 1.6–2.0 mm positive, A pilot hole
that is 10% smaller, low 150 rpm, Alternatively, a hinged connecting bar, near-far-far-near principle - one-third of cases, however, have
persistent lameness or complications, - Arthrodesis will cause a significant gait alteration with circumduction of the hindlimb. it can also affect the cat’s
ability to jump,
osteomyelitis
septic arthritis
was suspected
Combination of TPLO, medial and
lateral augmentation techniques
for the treatment of traumatic
stifle luxation in a cat
Bartolomé 2024
complete rupture of both cruciate
ligaments and marked disruption of the mid and caudal poles of the medial and lateral menisci were observed
persistent
instability with cranial tibial translation, internal and external rotation, and a positive caudal draw test. A lateral
augmentation suture was employed to address the persistent cranial tibial translation and internal rotation. To
successfully neutralise caudocranial and external rotational instability secondary to the caudal cruciate ligament
deficiency, a medial augmentation suture was placed
medial meniscal injury has been related to poorer outcomes in
cats with stifle luxation due to the development of osteoarthritis.
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