The early diagnosis of an acute compartmental pressure syndrome is often difficult, but can be facilitated by long term, up to several days, measurement of intra-compartmental pressures. A measuring system has been developed, together with its associated surgical and operational procedures, which may be applied in a variety of situations, including an immobile patient or a patient mobilized following surgery. If the technique is adopted as soon as the patient enters hospital, or immediately postoperatively, an acute compartmental syndrome may be recognized early and measures taken to alleviate its consequences.