Cruciate disease Flashcards
3 biomechanical functions of cranial cruciate ligament
To limit cranial translation of the tibia with reference to the femur
To limit hyperextension of the stifle
To limit internal rotation of the tibia with respect to the femur
Anatomy of the cranial cruciate ligament
The cranial cruciate ligament originates from the caudomedial aspect of the lateral femoral condyle
Courses in a craniomedial direction to insert on the cranial intercondyloid area of the tibia.
Cranial and caudal cruciate ligaments spiral around one another as they course distally
Anatomy the caudal cruciate liagment
arises from the lateral surface of the medial femoral condyle and passes caudodistally to insert on the lateral aspect of the popliteal notch of the tibia.
Cranial and caudal cruciate ligaments spiral around one another as they course distally
Three presentations of cranial cruciate ligament failure
Major trauma
Degeneration of the CCL with age
Ruptures in young, large breed dogs
Meniscus of the stifle - function
Load transmission and energy absorption
Rotational and varus-valgus stability
Lubrication
Allows joint congruity
Meniscus of the stifle - anatomy
held in place by ligaments and soft tissue attachments
cranial and caudal meniscal horns are firmly attached to bone via the ligaments
medial meniscus is firmly attached to the medial collateral ligament and the joint capsule via the coronary ligament, but the lateral meniscus lacks these attachments – important implications
Cranial cruciate ligament disease in the dog
Degenerative condition
Acute ruptures of normal ligament are uncommon
May only have a partial tear (stable joint but painful)
Osteoarthritis is often already present
Often a bilateral condition
Can affect young adults (usually large breeds)
Which is the most common cause of cranial cruciate ligament failure in dogs?
Degeneration of the CCL with age
Signalment of CCL disease in the dog
Breeds: Rottweilers, Chows, WHWTs, and labradors
Age: middle aged
Sex: females slightly overrepresented
Weight: overweight
Presenting signs of CLL disease in dogs
Pelvic limb lameness
Initially improve with rest and NASIDs
Lameness returns with exercise
Difficulty sitting/rising
Partially weight bearing at standing
Differential diagnoses for pelvic limb lameness
Cranial cruciate ligament rupture
Collateral ligament injury
Patellar luxation (medial or lateral)
Osteochondritis dissecans (OCD)
Neoplasia
Infection
Osteoarthritis
Polyarthritis
Caudal cruciate ligament rupture
Diagnosis of CCL disease
Gait analysis
Physical examination
- Cranial drawer
- Tibial compression test (tibial thrust)
Radiographic investigation
Gait analysis of CCL
Pelvic limb lameness
May be acute onset or chronic variable lameness
May have stiffness, reluctance to jump, and reduced exercise tolerance
Physical examination for CLL failure
Standing: comparison of two limbs (muscle atrophy)
Firm medial thickening of stifle
Effusion
Stifle painful on extension
Pathognomic instability (unless partial tear where there may not be instability)
Cranial drawer and tibial thrust
Radiographic investigation of CLL disease
Mediolateral and caudocranial views of both stifles
Joint effusion (reduction in size of infrapatellar fat pad)
Secondary arthritic changes
Rarely avulsion fractures may be seen
Meniscal injury - which is more frequent
Medial meniscal injury more common than lateral
Meniscal injury - History and presentation
Chronic history of lameness
Sudden deterioration
More lame than your average cruciate
Owners sometimes report a clicking or a popping sound
Large stifle effusion
Can occur AFTER surgical stabilisation of the stifle
Types of meniscal injury
bucket handle tears, detachment of the caudal horn and fibrillation.
Treatment of meniscal injury
Crushed or split meniscal tissue should be resected as it is a source of significant discomfort,
The damaged meniscal tissue should be carefully excised retaining as much undamaged meniscal tissue as possible.
Prognosis of meniscal injury
Dogs with meniscal tears have a worse prognosis than those without - they are more prone to wear of the articular cartilage and development of DJD and post cruciate stiffness/lameness
Partial cranial cruciate ligament injuries
Common
Clinical signs similar to complete ruptures (thickened and effused stifle)
Tibial thrust and cranial draw may be negative
Surgical exploration may be needed to confirm the diagnosis
Conservative treatment for CCL disease
Very strict exercise reduction for 6-8 weeks
Further 6 weeks gradually increasing controlled exercise
Weight control
If meniscal injury surgery is needed
Larger dogs will not do well with conservative management
OA will progress regardless but may be slowed by surgical intervention
Two types of surgical intervention for CCL injuries
Attempts to stabilise the joint by constraining the tibial thrust instability
Osteotomy techniques that alter the biomechanics of the stifle so that the CCL is no longer needed for joint stability
Attempts to stabilise the joint by constraining the tibial thrust instability
Modified over the top facial graft
Lateral fabello-tibial retinacular suture
Modified over the top facial graft
use of autogenous fascia lata +/- a portion of the patellar ligament to replicate the CCL
Limitations
- strength of attachment to the femur
- initial weakness of the graft
Can have good outcomes
Lateral fabello-tibial retinacular suture
Strong, permanent suture placed around lateral fabella, runs over lateral aspect of the stifle, through a drill tunnel in the proximal tibia
Limits cranial translation and internal rotation of tibia
Increased risk of infection due to permanent suture
Commonly the suture either stretches, breaks, or pulls away from its attachment
Osteotomy techniques
Tibial plateau levelling osteotomy (TPLO)
Tibial tuberosity advancement (TTA)
Cranial closing wedge osteotomy
Triple tibial osteotomy (TTO)
TPLO
Tibial plateau levelling osteotomy
Most common surgery performed by orthopaedic surgeons
Outcomes are consistently reliable
Alters the tibial plateau angle
Eliminates the cranial tibial thrust force
Little or no effect on the cranial draw instability
Good for large breed dogs with bilateral disease, boisterous or obese dogs, and dogs with a steep tibial plateau angle
TTA
Tibial tuberosity advancement
Involves moving the insertion of the patellar tendon more cranially to counter the cranial tibial thrust force
Prognosis of CCL surgery
Good
90%+ of patients returning to soundness
OA will progress in most patients despite surgical stabilisation
Post operative care for CLL surgery
Strict confinement and minimal exercise for 4-6 weeks post op
Osteotomies should be radiographed arounf 6-8 weeks after surgery
Exercise can be gradually increased over 6 weeks
Return to off lead activity by 12 weeks
Caudal cruciate ligament injury
Rarely ruptures in isolation
Usually in combination with other ligaments when the stifle is dislocated
Diagnosis by detection of a caudal draw sign
Surgery should not be necessary - conservative treatment/hydrotherapy
