Tibial Tuberosity Advancement Surgery (TTA)Surgery to repair cranial cruciate rupture
At Sydney Animal Hospitals we offer a Tibial Tuberosity Advancement Surgery ‘TTA’ procedure to surgically restore function after cranial cruciate ligament rupture. The procedure is suitable for larger and more active dogs, with either a full rupture or partial cruciate tear.
This operation is based on biomechanical analysis performed by Dr Slobodan Tepic, which revealed that in order to remove the shear strain from the cranial cruciate ligament the tibial plateau should be perpendicular to the patellar ligament.
There are two basic ways to achieve this; i) advance the tibial crest and ii) alter the alignment of the tibial plateaux to the patellar ligament to 90.
The TTA procedure advances the tibial crest, to stabilize the knee joint and is suitable for most patients from 5kg and above.
Pre-operative patient assessment
Every patient is assessed for the degree of lameness, overall alignment of the limb, stifle range of movement, as well as the degree of stability within the joint.
Pre-operative radiographic assessment
We often perform the radiographs immediately before the surgical procedure, under a continuous anaesthetic. The advantage of this is the patient only needs one anaesthetic and one hospital stay.
Surgery
The TTA surgery usually takes 60-90 minutes. The approach is to the medial (inside) of the stifle joint and the incision is in this area. The osteotomies are made with an oscillating saw and once the corrections are made a TTA rapid cage is inserted into the tibial crest osteotomy. The wound is closed in several layers and the skin sutured. We generally place a bandage and dressing over the surgical site. Patients are given intra operative IV antibiotics and pain medication. An iv analgesic infusion is continued for 24 hours post op, as well as oral antibiotics, anti-inflammatory and analgesic medications.
SAH TTA Discharge instructions
Medications
The following medications are suggested: A Non Steriodal anti inflammatory drug – NSAID (e.g. carprofen, meloxicam,) is used for a minimum of 7 days. We usually dispense 10 to 14 days of this type of medication, if you do not need the whole course some can be kept “in reserve” in case there is a post op flare up. These medications are pain relief and anti inflammatory. Oral antibiotics (clavulonate-amoxicillin – “Clavulox”) are used for 7 days. Zydax injections (an injectible glycosaminoglycan use to help prevent arthritis) are started immediately post-operatively and subsequent injections are given weekly for a total of 4 injections. Most TTA patients have a bandage for 7 days post op, however, this can be reduced to just a few days in some cases. Occasionally a dog is not suitable for a bandage and the wound is not dressed. These patients can have cold compressing to help with soothing and pain relief.
Exercise
Enforced rest is required for the first 6 weeks following TTA surgery. This means the dog should be confined to a small room or run for the duration of this period. Occasionally a patient will need to be crated if they are over active – please ask us if this is needed in your pet’s case. We often keep a patient in hospital for up to a week post op to ensure good rest. The only exercise allowed is short-duration (10 minutes maximum), slow walks on a leash for toileting purposes. Walking up and down flights of stairs, jumping up, or any uncontrolled activity must be avoided. Take care to avoid slipping when walking on wet or smooth surfaces. An old towel can be used as a hind-quarter sling if it is placed underneath the abdomen.
Post operative muscle therapy
Postoperatively, muscle therapy in the form of passive range-of-motion exercises can be performed after bandage removal. Ideally, all joints of the affected limb should receive physiotherapy 2 to 3 times a day but we instruct clients to concentrate mainly on the stifle joint if time is short. During each session, a minimum of 10 flexions and extensions should be performed on each joint. After flexion and extension of the individual joints, the entire limb should be cycled through its full, pain-free range-of-motion 10 times. It is very important never to force the joints or cause pain, but gently maneuver the limb through a range-of motion that is well tolerated. Please see the separate muscle therapy handout.
Longer-term follow-up and care
At around 6 weeks post-operatively we take a radiograph of the stifle to assess the progress of healing. This is usually taken under a general anaesthetic and is included in the initial cost of the TTA. All going well, controlled exercise on a leash may begin at this time. Leash walks should be minimal at first (15 to 20 minutes twice daily), and then gradually increased after 8 weeks post-operatively. Sit /stand exercises should also begin around 6 weeks post-operatively. This can be achieved during leash walking by commanding the dog to “sit” and just before the dog assumes the sitting position, the command to “walk-on” is given. This routine is repeated 10 or more times every walk and has the effect of building the quadriceps muscle mass, which is very important in rehabilitation following cruciate repair. There should be no unsupervised exercise, and running and jumping should be avoided during the 6 to 12 week post-operative period. Between 8 and 12 weeks, exercise can be increased slowly to 30 to 40minutes twice daily. Deep-water swimming for 10 to 15 minutes several times a week, if possible, is excellent therapy at this stage. By 12 to 16 weeks the patient should have returned to near normal activity. However, there is a large variation in how quickly individuals return to full function following TTA surgery. If there is not near normal activity by 12 to 16 weeks postoperatively, then make an appointment for reassessment.
To read more information:
TIBIAL PLATEAU LEVELING OSTEOTOMY (TPLO)
MEDIAL PATELLOFEMORAL LIGAMENT (MPL) REPAIRING PATELLA LUXATION