[Gravity suction drainage--an alternative to suction drainage in trauma surgery? A prospective randomized comparison in knee operations and hip joint alloarthroplasty?].

In two prospective randomized studies the common drainage system according to Redon was compared with the gravity system according to Robinson in 80 patients undergoing elective knee joint surgery and in 60 patients undergoing total hip replacement. By use of clinical criteria such as output volume and rate of hematomas in both groups no statistically significant difference could be established. However, there is a tendency to a lower hematoma rate in patients with knee joint operations and treated with the Robinson system. On the other hand after total hip replacement a tendency to lower hematoma rate was observed in the Redon group. These differences can be explained by the different output volumes after hip and knee joint operations. Probably the Robinson system cannot drain as much volume as the Redon system. A further explanation could be that after hip replacement an external compression cannot be sufficiently performed compared to the knee joint operations. Furthermore the remaining subfascial cavity after hip replacement should be drained with suction in order to reduce the extent of the cavity. This point of view is supported by the observation that the gravity system seems to be only an overflow one in clinical practice. The main advantage of the Robinson system is the significant lower pain score when removing the drainages and even when the drains are lying in situ. This advantage, however, is possibly a relative one, when the Redon drains are removed without suction. So the postulation that the Robinson system should be generally introduced in orthopedic surgery cannot be accepted. At the moment there are indications for both systems.(ABSTRACT TRUNCATED AT 250 WORDS)

RCT Entities:   Population Interventions Outcomes