Cruciate ligament tears are a topic of prime concern with any canine species-at-risk.
In some cases, despite efforts to prevent tears, they still occur.
Injury mechanism
Unlike in a human knee, in dogs, the cruciate ligament tends to tear gradually.
As humans are bipedal, upright walkers, the knee’s anterior cruciate ligament is situated horizontally in relation to the ground. This makes it less affected by gravital force. Therefore human ACL tears occur acutely, suddenly and fully, usually due to trauma.
In canines, tears are typically slow and occur with gradual degradation, followed by complete rupture. Well, usually followed by complete rupture, but not always.
Preventing full tears
If diagnosed and treated early, many pre-tears and partial tears can be prevented from becoming full, complete tears. Obviously, this can help the dog greatly with their function and save the owner major financial expense.
Diagnosis of CCL tears
- through observation
- performance of a drawer test, and
- with the help of radiographs and MRI
The drawer test
A therapist or a veterinarian will perform the drawer test using their hands.
The test is positive if the tibia slides too far forward. Picture it as pulling a drawer from a chest or cabinet.
Grades 0-5 are assigned, according to the amount of excessive tibial movement demonstrated in the test, in millimeters. Here is what the scoring means:
- 0 means no tear
- 1-2 indicates a partial tear
- 3 is partial to nearly-full
- 4-5 indicates full tears
Can a physical therapist make this assessment?
Yes, an experienced one can. However, they will likely ask you to see the veterinarian for a confirmation especially if they find a score of 3-5. If the dog has a score of 1-2, indicating a slight or partial tear, it indicates non-surgical treatment.
Treating partial CCL tears
Non-surgical approach includes:
- initial rest,
- use of medications prescribed by your vet (for pain, inflammation)
- physical therapy
- braces or wraps
Laser therapy
The use of laser therapy is very beneficial to facilitate healing at the tear site and relieve pain and inflammation.
I must clarify that laser therapy will not regenerate new ligament tissue nor help the torn part of the CCL to reattach. Rather, the cold laser helps strengthen and firmly bind the residual part still intact. It also helps form good scar tissue over the torn portion, giving tensile stability to the joint.
I have treated many dogs having partial tears. Physical therapy can reduce initial drawer test of Grade 2-3 to Grade 1 or even 0 after several sessions.
Most all of the cases I see with partial tears, that are rapidly diagnosed and treated early, are successful. In very rare instances have these cases go on to become full tears.
Example of physical therapy treatment for partial cruciate ligament tears
A typical example of physical therapy treatment for partial CCL tears consists of:
- Laser therapy over all sides of the stifle joint
- Ultrasound, and/or shock wave therapy, but cold laser is by far the most effective.
- Electrical stimulation in various formats: functional stim (FES) or NMES, over the thigh musculature if there is loss of tone and bulk (also called atrophy). Transcutaneous electrical stimulation (TENS) is effective for the reduction of acute pain.
- Manual techniques to increase blood flow to the injury such as massage and Reiki.
- Range of motion exercises to maintain mobility of the stifle and to prevent tightness.
- Strengthening to the hip and thigh musculature through sit to stand exercises, weight shifting, limb lifts, controlled leash walks on a level and inclined surfaces, controlled weight bearing with the dog placed over a physio roll, resisted exercises by a therapist using cuff weights, weighted sleds or therabands.
Activity restriction
Activity restriction must occur during the initial stages of healing as instructed by your veterinarian and therapist.
This may include
- temporarily keeping toe dog off wood floors and placing carpet runners
- restricting access to staircases
- blocking furniture which the dog would normally jump on or off of
If there are other pets in the house it may be necessary to separate them for a week or so to avoid heavy playing and contact interaction.
As the stifle joint regains tensile strength you can gradually increase to full activity.
In addition to therapy, products such as Dr. Buzby’s Toe Grips, stifle braces and soft stifle supports can help eliminate stress on the healing ligament.
Similar treatment options are used for dogs with complete or full ligament tears that cannot undergo surgery due to advanced age, seizure disorders, or medical conditions which pose a high risk for anesthesia.
Related articles:
Preventing Canine CCL Tears
Further reading:
Canine Cruciate Ligament Injury