• Aim: to replace the damaged cruciate with a graft, placed to mimic the course and function of the normal cranial cruciate ligament.
• Normal dogs bear weight on the tibial plateau; the cranial cruciate ligament prevents cranial movement of the tibia (and injury to the caudal medial meniscus) during weight-bearing.
• 'Over-the-top' technique places a graft of the patellar tendon and fascia lata through the joint and over the proximal and caudal aspect of the femoral condyle.
• 'Under-and-over' technique puts the autogenous graft under the inter-meniscal ligament before passing through the stifle joint - to provide an anchoring effect at the cranial cruciate ligament insertion site.
• The two attachment points of the graft should maintain the same relative distance as the joint moves so that there is no lengthening or shortening during joint movement and resulting graft failure; this is known as isometric placement of the graft.
• Several materials have been used for implants. Autogenous tissues include fascia lata and patellar tendon; exogenous materials have included suture materials (eg polydioxonone) and ligament replacement materials (eg multi-filament polyester, dacron, carbon fiber and 'gortex'). They are either intended to support the joint permanently or to act as temporary support and encourage the development of a new ligament. Exogenous materials are generally less successful and their use has been largely abandoned.
• Several techniques are practiced. The most common is a simple 'over-the-top' where a graft of fascia lata and a portion of the patellar tendon is passed through the joint and sutured to the lateral femoral condyle. Variations on this technique using tibial or femoral tunnels, or placement of the graft under the cranial intermeniscal ligament (the 'under-and-over' technique) have little clinical advantage and are used less commonly.

Uses

• Degenerative rupture of the cranial cruciate ligament Stifle: cranial cruciate ligament disease.
• Avulsion of the origin or insertion of the cranial cruciate ligament.

Advantages

• Relatively straightforward surgical technique.
• More isometric placement of the graft compared to extra-articular techniques.

Disadvantages

• Relatively invasive technique as graft passer must be placed through the caudal aspect of the joint.
• The graft is weaker then the native cranial cruciate ligament and weakens further with time.
• Instability returns in almost all cases as the graft lengthens, and the graft at best is acting as a temporary internal 'splint' for the joint.
• Clinically, outcomes have been shown to be less favorable than extra-articular techniques.

Technical problems

• Difficult to adequately tension graft.
• Difficult to achive secure fixation of the graft.

Alternative techniques

• Extra-articular sutures Stifle: extra-articular stabilization Stifle: crimped nylon fabellotibial sutures.
• Conservative management can be successful in dogs of less than 10 kg in weight without meniscal injury.
• Proximal tibial osteotomy technique allows dynamic stabilization of the joint during weight bearing; these include tibial plateau leveling osteotomy Tibial plateau leveling osteotomy (TPLO) , tibial tuberosity advancement Tibial tuberosity: advancement and triple tibial osteotomy Tibial tuberosity: osteotomy.

Time required

Preparation

• 30 minutes.

Procedure

• 30-60 min.

Decision taking

Criteria for choosing test

• Cranial cruciate ligament deficiency.
• Positive cranial drawer Stifle: cranial drawer test or tibial compression tests Tibia: compression test.

Risk assessment

• Moderate.