For a couple of months now, my mother has limped and hobbled with a very sore knee. She was recently diagnosed with a ruptured ligament and her doctors recommended using a brace. The purpose of the brace, in her case, was to immobilise the knee joint, so it was “locked” in an extended position which would reduce the pain until her surgery – which thankfully was today.

For Mum, the brace will hopefully be a short term aid to healing, but what role do braces or orthoses play in the management of musculoskeletal conditions and can braces be used on dogs?

What are braces or orthoses?

Orthoses are devices to assist or limit joint movement. They may include braces, wraps, sleeves, strapping or bands. These devices are commonly used for animals with ligament or tendon problems like ruptures to the calcaneal tendon (Achilles tendon in humans), sub-luxating patella or as a non-surgical management tool for cranial cruciate ligament insufficiency.

Orthoses can be made of a range of materials including rigid or semi-rigid plastic or fibreglass, fabric or strapping. They are often custom made for a dog based on a mould of the affected limb. Orthoses can be rigid, flexible or hinged to allow some motion, depending on the purpose of the device.

How do braces work?

For dogs with chronic conditions such as a weakness in the cranial cruciate ligament or patella luxation, an orthosis of some kind may be considered for conservative management of the condition.

Braces are placed across a joint to align the bones vertically above and below an unstable joint. Depending on the design of the brace, it may limit the joint’s range of motion and aid joint stability by neutralising the forces from motion to support the ligaments of the joint.

Orthoses may also be used to change the position of joints in non-functioning limbs. For example, in dogs with sub-luxating patella that rotates the tibia in relation to the femur, a brace may be considered to correctly align the lower limb.

Are braces (orthoses) effective?

In human studies, bracing unstable joints has been shown to:

• Enhance joint proprioception (sense of the position of the joint).

After exercise joint proprioception worsens. It is thought that the efficiency of the mechanoreceptors in the joint, ligaments, tendons, muscles and skin worsens after exercise due to fatigue, build up of chemical products such as lactate, and increased joint laxity. Braces provide additional stimulation to the receptors in the skin of the joint position and movement which may compensate for the decline in efficiency of the joint and muscle receptors with exercise.

• Allow the affected joint to relax which reduces fatigue in the limb.

When the joint is affected by an inflammatory condition such as osteoarthritis, resting the joint helps reduce inflammation and the associated pain.

• Provide the joint with physical support and protection from impact.

• Slow joint motion to allow the surrounding muscles to respond and control movement.

In a study of humans wearing a knee brace it was found that hamstring muscle activations increased pre-landing which inhibited the quadriceps engaging on landing. This in turn reduced shear forces on the knee. Further, the knee brace increased activation of the gluteals and femoral biceps at peak push off. This has the effect of stabilising the pelvis and reducing loading on the knee when landing.

The findings from human studies are reflected in canine studies.

In a study of dogs with cranial cruciate ligament weakness, after wearing stifle orthotics over a 90 day trial period, dogs showed improved weight bearing on the affected limb by 5.1%. It was noted, that this study did not investigate the affects of the stifle orthotics on the dog’s kinematics.

In dogs with ruptures of the gastrocnemius tendon, braces or casts have been used effectively to aid healing. With this type of injury, regardless of whether surgery is required or not, a brace needs to be carefully designed to allow controlled reloading of the tendon. With tendon injuries of this type, loading is required for proper healing and restoration of full breaking strength.

Is a brace alone enough to restore full joint function?

When braces are used to aid recovery from injury or surgery, rehabilitation with physical therapy is also recommended. A massage and physical therapy programme will benefit a dog recovering from an injury in the following ways:

• Properly align new muscle, ligament, and tendon fibres

• Increase the number of collagen fibres

• Restore the strength of the soft tissue

• Improve vascularity (circulation to the affected area)

• Restore range of motion

Would a brace help my dog?

If your dog has a musculoskeletal condition that you think may benefit from an orthosis, please discuss your dog’s diagnosis with your vet or vet specialist.

Full Stride may assist with a rehabilitation programme based on your vet’s diagnosis. For more information please email me at jlconlon@fullstride.com.au.

You can also stay up to date by following Full Stride on Facebook

Until next time, enjoy your dogs.

Sources:

Bottoni G, Heinrich D, Kofler P, Hasler M & Nachbauer W (2014) “Effect of Knee Supports on Knee Joint Position Sense after Uphill and Downhill Walking. A Test Using a Hiking Simulation Method” Journal of Ergonomics November 04, 2014

Chuang, M, Lee, Y & Lee, H. (2015) “Effects of functional knee brace on lower extremity muscle activations after anterior cruciate ligament reconstruction” 33rd International Conference on Biomechanics in Sports, Poitiers, France, June 29 – July 3, 2015

Hamann N, Heidemann, J, Heinrich, K, Wu, H, Bleuel, J, Gonska, C & Brüggemann, G (2014) “Stabilization effectiveness and functionality of different thumb orthoses in female patients with first carpometacarpal joint osteoarthritis” Clinical Biomechanics 29 (2014) 1170–1176

Millis, D.L, Levine, D & Taylor R.A (ed) (2004) Canine Rehabilitation and Physical Therapy, Elsevier Inc, Missouri USA

“How I manage ‘Achilles complex’ tendinopathy” Proceedings – Small Animal, 25th ECVS Annual Scientific Meeting, July 7 -9 2016