Strength gains in ostaPek composite enable coLigne to engineer specialized interbody cage designs that deliver contralateral reduction and bone from a unilateral and strictly sagittal approach. Gemtira cage walker instrumentation use sagittaly controlled percussion to translate Contra and IPSI Gemitra cages to the contralateral and ipsilateral disc space. Less blood loss. Less time. Better reduction, stabilization and ostaPek composite built for bone support.