Rupture Of The Cranial Cruciate Ligament

What are the treatment options?

Various treatment options are available. The best treatment option for each dog can only be recommended following thorough assessment including the degree of laxity/looseness of the knee, patient size and lifestyle, and conformation (limb shape). The cruciate ligament itself is unable to heal once it is damaged, so treatment is focused on stabilizing the knee joint in the absence of a cranial cruciate ligament.

1.Non-surgical management

Non-surgical management is seldom recommended, except where the risks of a general anaesthetic or surgery are considered excessive (e.g. patients with severe heart disease, uncontrolled hormonal disorders or immune conditions, etc.)

In this circumstance, four basic methods are usually recommended:

• Body weight management
• Exercise modification
• Anti-inflammatory / pain relief medications
• Nutraceutical supplements (e.g. glucosamine, chondroitin sulphate, pentosan polysulphate, Green-lipped Mussel extract)
• The knee may eventually stabilize by formation of fibrous scar tissue around the knee although this may take many months or even years in many patients.

2.Surgical ligament replacement

Over the last 30 years, a number of techniques have been developed, aimed at replacing the cranial cruciate ligament either with the dog’s own tissues or with a synthetic ligament prosthesis. Where this method is required, we prefer to use a recently-developed material known as Fiberwire® (Arthrex, Naples, FL, USA) which is mechanically superior to the commercially available alternatives, and has been shown to be effective in a large number of clinical cases. A system has been developed to allow placement of the Fiberwire® around the outside of the joint so that it closely mimics the function of the cruciate ligament.

3.Mechanical osteotomy procedures

Over more recent years, several techniques have been developed which change the mechanics of the knee joint such that the joint becomes stable in the absence of a functional cranial cruciate ligament. These procedures rely on cutting the tibia (shin bone) and fixing it in a new position in such a way that the load-bearing and muscle forces on the knee are balanced, neutralising tendency for the shin bone to shift relative to the thigh bone.

We use two major techniques (dependent on individual anatomy, conformation and presence of other diseases):

• Tibial Plateau Levelling Osteotomy (TPLO)
• Tibial Tuberosity Advancement (TTA)

Although these techniques are slightly more complex, patients may actually recover more quickly than with some ligament replacement techniques, with use of the operated leg within 1-2 days, and resolution of visible lameness within a few weeks.

4.Total Knee Replacement (TKR)

Occasionally, long-term cartilage damage and osteoarthritis following cranial cruciate ligament rupture can be so severe that comfortable, functional knee use cannot be recovered. In this circumstance, replacement of the joint surfaces of both the tibia and femur with metal and plastic joint replacement implants may be considered. This new technology is now routinely available at our facility.