Orthozip / Lateral Suture Starting at $2500
Extracapsular suture repair is a leading option for the treatment of unstable stifles due to cranial cruciate ligament insufficiency. Lateral suture repair for dogs has been around for decades and has helped tens of thousands of dogs. Although osteotomy techniques like TPLO and TTA have become the standard of care for large breed and athlete dogs, the extracapsular repair has remained a very useful technique that veterinary surgeons can perform in your hospital when referral is not an option.
This procedure has changed over the years to address the weaknesses of the original technique. The development of a tensioning and crimping system with nylon leader line was a quantum improvement over the original hand-tying system. Ongoing improvements have focused on increasing the strength of the implanted material, limiting its stretch, increasing the strength of the anchoring points, and maximizing isometry so the suture is uniformly tight during the entire range of motion. New systems for this repair have incorporated these new features. Remember, however, that all these techniques are still mechanically extracapsular repairs. This means that they mechanically prevent cranial subluxation and nearly eliminate the normal internal rotation of the tibia.
Most of the newer implants, whether a suture, tape, or loop, are made of ultra-high molecular weight polyethylene. This material is much stronger than nylon leader line and does not stretch. The anchoring points are bone tunnels with buttons or interference screws, screw-in anchors with holes or flanges, or screw-in anchors with the material already attached. The implants’ placement counters the force of subluxation from the isometric points on the distal femur and proximal tibia.
The Everost OrthoZIP system of lateral suture repair for dogs was developed by the same bioengineer who created the original nylon leader line tensioning and crimping system. This system employs a self-tightening, ultra-high-molecular-weight polyethylene loop that is placed over titanium anchors with a cancellous thread profile and a “sewing-bobbin” shaped head to retain the loop. After arthrotomy, inspection, and treatment of any meniscal injuries, the anchor points are identified, pre-drilled, and the anchors placed. The loop goes over the anchors, which we tighten by pulling on the two free ends. The loop maintains the tension without any knotting or crimping. Several sizes are available to cover a full range of patient sizes.
Author: R. Randy Basinger DVM, DACVS