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A new spiral linking technique for tendon repair in which one end of the tendon is spiralled around the other end has been developed. Using pig trotter extensor tendons, the Pulvertaft weave technique was compared with this new technique. Twenty-five repairs using each technique were tested by tensile loading with an Instron testing machine. The spiral linking technique matched the strength of Pulvertaft method: the mean peak loads were 102 and 105 N, respectively. The Pulvertaft weave was stiffer than the spiral linking technique: mean stiffness of 11.1 and 6.7 N/mm, respectively. The spiral linking technique also absorbed considerably more energy: energy absorbed prior to failure to 90% of peak load, 1.75 and 1.13 kN mm, respectively. In conclusion, the spiral linking technique appears as strong as the Pulvertaft weave and we believe it is easier to perform.

Pulse‐echo‐overlap measurements of ultrasonic wave velocity have been used to determine the dependences of the elastic stiffness moduli of polycrystalline cementite (Fe3C) on temperature in the range 75–295 K and hydrostatic pressure up to 0.1 GPa at room temperature. The longitudinal stiffness (CL) and adiabatic bulk modulus (BS) stiffen, while the shear stiffness (μ) and Young's modulus (E) soften with decreasing temperature. The ultrasonic velocities increase approximately linearly with pressure, much more steeply for the longitudinal than the shear mode. The values obtained at 295 K for the hydrostatic‐pressure derivatives (∂CL/∂P)P=0, (∂μ/∂P)P=0 and (∂BS/∂P)P=0 of cementite are 7.9 ± 1.7, 1.4 ± 0.1 and 6.1 ± 1.7, respectively: the zone‐centre acoustic phonons stiffen under pressure. The longitudinal (γL), shear (γS) and mean (γel) acoustic‐mode Grüneisen parameters of cementite are positive; γS is markedly smaller than γL indicating that the shear acoustic modes are less anharmonic than the longitudinal modes.

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