A medical support arm comprising: - a holding end for gripping and operating the support arm; - a coupling end for connecting the support arm to a patient receptacle such as e.g. an operating table; - a rotary joint located at the coupling end for pivoting the support arm about a pivot axis and for tilting the support arm about a tilting axis which intersects with the pivot axis; - a clamping mechanism with which the rotary joint optionally: a) can be locked so that rotation of the support arm about both the pivoting and the tilting axis is prevented; b) can be released so that the support arm can rotate about both axes (A1, A2) freely; - a release lever located at the holding end for releasing the clamping mechanism; - a support bar for supporting a medical device, which support bar extends between the holding end and the coupling end; and - a force transmission device (41, 43, 45) for transmitting a release force from the release lever to the clamping mechanism, which force transmission device is arranged in and/or on the support bar, characterized in that - the rotary joint: a) permits rotating the support arm only about the tilting axis and the pivot axis; b) comprises a tilting device for tilting the support arm about the tilting axis, wherein the tilting device comprises a tilting element and a cylindrical running surface (22a, 24a) on which the tilting element sits, so that the cylindrical running surface and the tilting element can rotate relative to one another around the tilting axis; c) comprises a pivoting device for pivoting the support arm about the pivot axis, wherein the pivoting device comprises a guide ring and at least one ring guide surface (30, 32) receiving the guide ring so that the guide ring and the at least one ring guide surface can rotate relative to one another about the pivot axis; and d) comprises a central body (22, 24) located at the center of the rotary joint and on which the cylindrical running surface (22a, 24a) and the at least one ring guide surface (30, 32) are formed; - the tilting element as part of the clamping mechanism also acts as a collar in such a way that by pinching the central body (22, 24), this clamps both the tilting device and the pivoting device against rotation. - a holding end for gripping and operating the support arm; - a coupling end for connecting the support arm to a patient receptacle such as e.g. an operating table; - a rotary joint located at the coupling end for pivoting the support arm about a pivot axis and for tilting the support arm about a tilting axis which intersects with the pivot axis; - a clamping mechanism with which the rotary joint optionally: a) can be locked so that rotation of the support arm about both the pivoting and the tilting axis is prevented; b) can be released so that the support arm can rotate about both axes (A1, A2) freely; a) can be locked so that rotation of the support arm about both the pivoting and the tilting axis is prevented; b) can be released so that the support arm can rotate about both axes (A1, A2) freely; - a release lever located at the holding end for releasing the clamping mechanism; - a support bar for supporting a medical device, which support bar extends between the holding end and the coupling end; and - a force transmission device (41, 43, 45) for transmitting a release force from the release lever to the clamping mechanism, which force transmission device is arranged in and/or on the support bar, - the rotary joint: a) permits rotating the support arm only about the tilting axis and the pivot axis; b) comprises a tilting device for tilting the support arm about the tilting axis, wherein the tilting device comprises a tilting element and a cylindrical running surface (22a, 24a) on which the tilting element sits, so that the cylindrical running surface and the tilting element can rotate relative to one another around the tilting axis; c) comprises a pivoting device for pivoting the support arm about the pivot axis, wherein the pivoting device comprises a guide ring and at least one ring guide surface (30, 32) receiving the guide ring so that the guide ring and the at least one ring guide surface can rotate relative to one another about the pivot axis; and d) comprises a central body (22, 24) located at the center of the rotary joint and on which the cylindrical running surface (22a, 24a) and the at least one ring guide surface (30, 32) are formed; a) permits rotating the support arm only about the tilting axis and the pivot axis; b) comprises a tilting device for tilting the support arm about the tilting axis, wherein the tilting device comprises a tilting element and a cylindrical running surface (22a, 24a) on which the tilting element sits, so that the cylindrical running surface and the tilting element can rotate relative to one another around the tilting axis; c) comprises a pivoting device for pivoting the support arm about the pivot axis, wherein the pivoting device comprises a guide ring and at least one ring guide surface (30, 32) receiving the guide ring so that the guide ring and the at least one ring guide surface can rotate relative to one another about the pivot axis; and d) comprises a central body (22, 24) located at the center of the rotary joint and on which the cylindrical running surface (22a, 24a) and the at least one ring guide surface (30, 32) are formed; - the tilting element as part of the clamping mechanism also acts as a collar in such a way that by pinching the central body (22, 24), this clamps both the tilting device and the pivoting device against rotation.