The study assesses the efficacy of commonly used suture materials with commonly described arthroscopic knotting techniques in as close a physiological pattern as possible. The investigation was carried out in three phases. Initially the suture material strength was tested. The suture was then tested to failure using the different knotting techniques. Finally the test was repeated after soaking the suture with normal saline. A Hounsfield tensometer was utilised with a load cell of 1000N, strain rate of 25mm/min, bar separation of 7.5mm and standard temperature and pressure. Suture material tested was 2 ethibond, 1 PDS and 1 Panacryl. Knotting techniques compared were the Tennessee slider, Tautline hitch, Duncan Loop, SMC knot and Surgeon’s knot. Two surgeons tied each knot 10 times after first becoming practiced with each technique. Each knot was tested to failure on 10 sequential experiments. Ultimate strength of the suture material and of the knotting techniques was assessed. In addition the mode of failure, whether the knot slipped or suture material fractured was investigated. As expected, 2 ethibond has a higher ultimate strength than either 1 PDS or 1 Panacryl. The Tautline hitch and Surgeon’s knot had a significantly lower slippage rate when compared to the other knotting techniques. (P value <
0.002). The Tennessee slider, Duncan Loop and SMC knots slipped in more than 50% of experiments. No difference was observed when the suture material had been soaked in normal saline. The number of half hitches required to provide maximum knot holding capacity was 3, confirming previous experimental findings by other investigators. The Tautline hitch is recommended for use with all suture materials due to low slippage rates, ease of tying, ease of sliding and overall high knot strength
