We show that the magnetostriction hysteresis curves, measured at different temperatures by Chabanenko et al (1998 Supercond. Sci. Technol. 11 1181) in a La1.85Sr0.15CuO4 single crystal, can be well reproduced by exploiting the critical state framework proposed by Ikuta et al (1993 Phys. Rev. Lett. 70 2116) to describe this phenomenon in high T-c superconductors, provided that the role of the Meissner current circulating at the surface of the crystals is taken into account.