Abstract: A completely disposable, permanently assembled drill for perforating bone structures, which includes a generally annular drill body. A primary drill member is slidably and rotatably received in the distal end of the drill body. A driver is slidably and rotatably received in the proximal end of said drill body. A pin and slot-type spring biased clutch is disposed on the confronting surfaces of the drill member and driver. The pin of the clutch projects through the triangular openings and the sidewall of the drill body so as to limit the throw of the clutch and to link the drill body and drill member together. The interaction of the pin against the triangular side of the slot in the drill body produces a component of force which tends to urge the clutch apart. When the drill is placed against the bone structure with a force sufficient to overcome the spring bias, the clutch will engage and the driver and drill member and the drill body will rotate together.

Abstract: A completely disposable, permanently assembled drill for perforating bone structures, which includes a generally annular drill body. A primary drill member is slidably and rotatably received in the distal end of the drill body. A driver is slidably and rotatably received in the proximal end of said drill body. A pin and slot-type spring biased clutch is disposed on the confronting surfaces of the drill member and driver. The pin of the clutch projects through the triangular openings and the sidewall of the drill body so as to limit the throw of the clutch and to link the drill body and drill member together. The interaction of the pin against the triangular side of the slot in the drill body produces a component of force which tends to urge the clutch apart. When the drill is placed against the bone structure with a force sufficient to overcome the spring bias, the clutch will engage and the driver and drill member and the drill body will rotate together.

Abstract: A surgical retractor assembly includes a support post having a lower portion and an upper portion, with the lower portion having an adjustable clamp for attaching the post to a rail provided on a surgical operating table. This clamp is capable of attachment to the rail over a flexible surgical drape. A screw mechanism is associated with the clamp so that the clamp can be attached and adjusted by the operator in an area above the rail on the surgical table. An extension rod is adjustably connected to the post and is adapted to extend in a direction generally over a patient on the operating table. A rigid ring member is connected to the extension rod for positioning a plurality of retractor blades for use on a patient. At least one retractor blade is mounted on the ring member.