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In vivo studies on disc mechanics show loss of fluid from the intervertebral disc (IVD) during loading and full recovery during rest. Previous work indicated that in vitro recovery is hampered after static loading. The aim of the present study was to investigate the role of the endplate after dynamic and static loading on mechanical recovery in vitro. Lumbar spines (caprine) were obtained from the local slaughterhouse and stored frozen. Twenty-four intervertebral discs were thawed and subjected to a compression test in a saline bath (37°C). The discs were pre-loaded at 20N for 15min. Three 15-min loading cycles (static: 2.0MPa or dynamic: average load 2.0MPa at 0.5Hz) were applied, each followed by a 30-min period of unloading (20N). After this protocol, the endplates of half of the discs were blocked with silicone paste and the long-term recovery protocol was applied; the discs were subjected to a single loading …