A seal such as a releasably attachable upper seal (200, 202, 204) for a trocar system (10, 12)includes a rigid distal support (20), a rigid proximal support (40), a flexible seal (60) having upper portions sandwiched between the supports, and a ring (90, 92) disposed between the flexible seal (60) and the lower support (20). The opening in the ring (90, 92) is sized smaller than the opening in the lower support (40). Further seals are disclosed which include a flexible seal rotatably supported by the support. Cannulas and trocar systems employing such seals are also disclosed.Linvention porte sur un joint tel un joint supérieur pouvant être fixé de manière détachable (200, 202, 204) pour un trocart (10, 12), comprenant un support distal rigide (20), et un support proximal rigide (40), un joint flexible (60) doté de parties supérieures prises en sandwich entre les supports, et un anneau (90, 92) disposé entre le joint flexible (60) et le support inférieur (20). Louverture de lanneau (90, 92) est de dimension inférieure à celle de louverture du support inférieur (40). Linvention concerne dautres joints comprenant un joint flexible soutenu rotatif par le support. Elle porte également sur des canules et des trocarts utilisant ces joints.
