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Abstract Background The use of an interference fit wedged bone plug to provide fixation in the tibial tunnel when using bone-patellar tendon-bone autograft for anterior cruciate ligament reconstruction offers many theoretic advantages including the potential to offer a more economical and biological alternative to screw fixation. This technique has not been subjected to biomechanical testing. We hypothesised that a wedged bone plug fixation technique provides equivalent tensile load to failure as titanium interference screw fixation. Methods In a controlled laboratory setting, anterior cruciate ligament reconstruction was performed in 36 bovine knees using bone-patella-bone autograft. In 20 knees tibial fixation relied upon a standard cuboid bone block and interference screw. In eight knees a wedge shaped bone block with an 11 mm by 10 mm base without a screw was used. In a further eight knees a similar wedge with a 13 mm by 10 mm base was used. Each specimen used a standard 10 mm tibial tunnel. The reconstructions were tested biomechanically in a physiological environment using an Instron machine to compare ultimate failure loads and modes of failure. Results Statistical analysis revealed no significant difference between wedge fixation and screw fixation (p = 0.16), or between individual groups (interference screw versus 11 mm versus 13 mm wedge fixation) (P = 0.35). Conclusions Tibial tunnel fixation using an impacted wedge shaped bone block in anterior cruciate ligament reconstruction has comparable ultimate tensile strength to titanium interference screw fixation.

Operating conditions are described for the qualitative and quantitative determination of dantrolene sodium by high-pressure liquid chromatography. A 10-mum porous silica column was employed, using carbon tetrachloride-dimethylformamide (90:10) as the mobile phase. The flow rate was 2.0 ml/min (1800 psig), and the peaks were detected at 375 nm. The analysis of a dosage form can be carried out within 30 min with an accuracy of 3.1%. The results agree favorably with those obtained with a modified spectrophotofluorometric method.

Parameters are described for the qualitative and quantitative analysis of a mixture of isoniazid and its acetyl derivative. The compounds are chromatographed on an octadecylsilane column, using absolute methanol-distilled water (60:40) at pH 2.5 containing 0.01 M dioctyl sodium sulfosuccinate. The flow rate was 2.0 ml/min (2500 psig). The separation and quantification are applicable to plasma and urine samples. The determination in each biological fluid can be achieved in approximately 90 min with percentage accuracies for isoniazid of 5.25 and 7.45 and for the acetyl derivative of 4.47 and 1.56 in plasma and urine, respectively.