The compartment syndrome is in fact secondary to intracompartmental hypertension which creates ischemia of the muscles, nerves, vessels, and anterior tibial and peroneal arteries in the leg. Described in the 19th century, the clinical picture is better known when progressing either in the acute form or in the chronic form. Diagnosis depends basically on the measurement of intramuscular pressure; treatment, at least initially, apart from subcutaneous aponeurotic decompression, also calls for hyperbaric oxygen therapy. The latter is particularly indicated in those cases bordering on surgical and medical treatment, for preventing deterioration and improving muscular possibilities in the post-surgical period. At the present time, the physiopathology of the condition is still poorly understood. The whiplash syndrome was well described by Martorelli and is due to rupture of the muscular veins of the calf. The clinical picture is often ambiguous and can suggest underlying phlebitis. The triad of symptoms --pain, disability and ecchymosis-- generally enables a diagnosis to be made, with treatment consisting primarily of immobilization. As for Bywaters' syndrome (crush syndrome), it is still very topical. The original description of the clinical picture by Bywaters during the bombardment of London in 1942 has been replaced by the picture resulting from large scale accidents that are part of modern society. The picture is still highly dramatic and if untreated progresses to acute renal insufficiency. Treatment has certainly changed and hyperbaric therapy (administered at two or three atmospheres) is a valid adjuvant to basic treatment and modifies the progress of the phenomenon with entirely satisfactory results.