DIAG IM3 - Page 178

15Joint 5 Dental Surgery Equipment & Instrumentation Nylon Lateral Button Suture www.vetinst.com Suture anchor pins (page 170), suture screws (page 170), devices such as interference screws (page 166) are examples of some of the devices available for achieving suitable anchorage in the femoral condyle. For techniques using any of these anchors, the high strength braided materials are again recommended because of their increased abrasion resistance against the anchor. Mono-filament nylon remains the most commonly used material for lateral suture techniques. Although less strong and more prone to premature failure than the braids, many surgeons prefer its handling characteristics. Its mono-filament nature makes it more forgiving to aseptic technique and its ability to stretch allows it to also be more forgiving to isometric placement. These can be very distinct advantages. Despite this, maximising isometry should always be the aim as it will help limit the joint becoming excessively tight or excessively loose during flexion/extension, prolonging the cycle life of the prosthesis and its attachments as well as providing better mechanical function through a greater range of motion. Isometry for lateral suture techniques is improved by using tibial anchorage points more caudal and more proximal than originally described. The most isometric anchorage points on the tibia are in the region of the Tubercle of Gerdy or Gerdy’s Sister (the two prominences either side of the long digital extensor grove – see fig 1.). Although Gerdy’s sister may provide the more isometric anchorage point of the two, the Tubercle of Gerdy itself may provide a more mechanically advantageous anchorage point in resisting cranial tibial thrust. Suture Screws Fig 1 Suture Anchor Pins Using the most frequent method whereby the suture is placed through a tibial bone tunnel and then back in a loop under the patella ligament (see lateral suture technique) becomes progressively problematic as the tibial bone tunnel is placed more caudally. The suture assumes a more unpredictable path under the patella ligament on its return loop, which may then start to impinge G&'F7V"7G'V7GW&W26VFrFPFW&fV&6GRbFW&R&R7FVFW2&W6VBFR&v`FRFW&G&6V&FvRFR7WGW&R'V"fW"FW6RGW&rfWWFV6&W7VFr'&6''V6rBࠥ7WGW&R6"VwFVF6w&FRVG&ֆvV7V"vVvBǖWFVRTuR2FRFW&b66Rf"FRFW&'WGF2&fFrW6VV@&6F&ƗG7G&VwFB66'6'Fv7B&Vr6gBVVvF֖֗6R7WGW&RvV"FW6R'WGF2&R&V6VFVBf"W6RvFFV6VW2ࠤFW&'WGFFV6VW26fRF2&&V2&FVG2bFRƖR70F&VvFR6R&RGVVVW&vrg&FR6RRFRFW&7V7BbFRF&FR&VvbFRGV&W&6RbvW&GF26vRFW2FR&7FW62W72Ɩ&RF'V"v7BFRFW&fV&6GRBFRvR2WB&R&VƖ&ǒWG&67V"f"6VFǒ6FVBF&&RGVV7W&vV2fBFW&'WGFFV6VW2V6W"FW&f&vV6&VBvFFR7FF&BFW&7WGW&RFV6VRࠤv7G&VwF'&G27V62Ɩvf&*&R7G&vW"FFRTuP'WGF2BvW&RfW'vV"6&2Fr2WV7FVB7V62vFfW'Vg"7FfRFVG2vW&RvB6WG'6B&P6WfVB"6VV7BFVG2vF7FVWW"F&FVRvW2FWfBFR7G&vW"FFV'WGF26&RW6VB7FVBfr"BvPcrࠤ2vFFR&RG&FFFW&7WGW&RFV6VW2FR6&vP6FFRfV&7V7BbFRB2FRFW&f&Vf&VF&ƖvVBvW&RFRFW&f&Vf&VF&ƖvVBffW'07Vff6VB6V7W&G6V6B&RGVVfV&&RGVV’"7WGW&R6"&RW6VB7FVB&fFrfV&6&vR@W7B7&BW7BF7FFFRFW&f&VFRƖvf&*6FvvPvRc&RWW2bFV6VW2FW6vVBF7V6f6ǒFPGfFvRb6&VBF&BfV&&RGVV2&V6W6RbFP7&V6R7WGW&Rv&rVwFr7G&WF6'&G2&R&V6VFV@f"FV6VW2ffrGv&RGVV2ࠥFFV'WGF0c fr