A surgical rib retractor (66; 238; 462), comprising: a housing (68; 240; 464) having a first shoulder (70; 242; 468) and defining an actuator guide opening (168; 354); a body (72; 244; 466) pivotably coupled to the housing (68; 240; 464) and having a second shoulder (74; 246; 470); a first arm unit (76; 248; 472) pivotably coupled to the first shoulder (70; 242; 468) and configured to receive one rib; a second arm unit (78; 250; 474) pivotably coupled to the second shoulder (74; 246; 470) and configured to receive another rib; a first arm actuator (80; 252) constrained to be rotatable relative to the first shoulder (70; 242; 468) and coupled to the first arm unit (76; 248; 472) to pivot the first arm unit (76; 248; 472) as the first arm actuator (80; 252) is rotated; and a second arm actuator (82; 254) constrained to be rotatable relative to the second shoulder (74; 246; 470) and coupled to the second arm unit (78; 250; 474) to pivot the second arm unit (78; 250; 474) as the second arm actuator (82; 254) is rotated; a drive actuator (84; 256; 476) configured to pivot the body (72; 244; 466) relative to the housing (68; 240; 464); characterised in that the surgical rib retractor further comprises a pawl arm (174; 368; 492); wherein the body (72; 244; 466) comprises a ratchet gear (178; 372; 486) and a drive gear (172; 366; 478); wherein the pawl arm (174; 368; 492) has a pawl (176; 370; 496) which is biased against the ratchet gear (178; 372; 486); wherein the drive actuator (84; 256; 476) comprises an actuation gear (170; 356; 484); wherein the actuator guide opening (168; 354) is sized to accept the actuation gear (170; 356; 484) and align it with the drive gear (172; 366; 478) for turning the drive gear (172; 366; 478); and wherein the drive actuator (84; 256; 476) comprises a pawl arm deflection portion (180; 374) configured to engage the pawl arm when the drive actuator is pushed down, thereby releasing the pawl from the ratchet gear when desired. a housing (68; 240; 464) having a first shoulder (70; 242; 468) and defining an actuator guide opening (168; 354); a body (72; 244; 466) pivotably coupled to the housing (68; 240; 464) and having a second shoulder (74; 246; 470); a first arm unit (76; 248; 472) pivotably coupled to the first shoulder (70; 242; 468) and configured to receive one rib; a second arm unit (78; 250; 474) pivotably coupled to the second shoulder (74; 246; 470) and configured to receive another rib; a first arm actuator (80; 252) constrained to be rotatable relative to the first shoulder (70; 242; 468) and coupled to the first arm unit (76; 248; 472) to pivot the first arm unit (76; 248; 472) as the first arm actuator (80; 252) is rotated; and a second arm actuator (82; 254) constrained to be rotatable relative to the second shoulder (74; 246; 470) and coupled to the second arm unit (78; 250; 474) to pivot the second arm unit (78; 250; 474) as the second arm actuator (82; 254) is rotated; a drive actuator (84; 256; 476) configured to pivot the body (72; 244; 466) relative to the housing (68; 240; 464); characterised in that the surgical rib retractor further comprises a pawl arm (174; 368; 492); wherein the body (72; 244; 466) comprises a ratchet gear (178; 372; 486) and a drive gear (172; 366; 478); wherein the pawl arm (174; 368; 492) has a pawl (176; 370; 496) which is biased against the ratchet gear (178; 372; 486); wherein the drive actuator (84; 256; 476) comprises an actuation gear (170; 356; 484); wherein the actuator guide opening (168; 354) is sized to accept the actuation gear (170; 356; 484) and align it with the drive gear (172; 366; 478) for turning the drive gear (172; 366; 478); and wherein the drive actuator (84; 256; 476) comprises a pawl arm deflection portion (180; 374) configured to engage the pawl arm when the drive actuator is pushed down, thereby releasing the pawl from the ratchet gear when desired.