Fast development of high intra-abdominal pressure when a trained participant is exposed to heavy sudden trunk loads

Study Design.
This study focused on intra-abdominal pressure (IAP) during sudden trunk loads. Ten participants were exposed to heavy, sudden trunk loads as they might occur during patient handling.

Objectives.
The aim was to study the development of intra-abdominal pressure when well-trained participants cope with heavy, sudden trunk loads. It is hypothesized that high IAP develops sufficiently fast to be present when the large torques act on the low-back structures.

Summary of Background Data.
Well-trained sportsmen expose themselves to heavy sudden loads of the trunk without getting injured, but it is unknown how they cope with these loads. Do they use IAP? IAP is believed to play a significant role in spine stability, but this has only been documented in experimental studies with light trunk loads.

Materials and Methods.
Ten well-trained judo and jujitsu fighters were exposed to heavy sudden trunk loads through imitated patient handling situations in which the patient fell, and the fighters were to hold the patient and prevent the fall. IAP was measured with a catheter in the stomach. Along with the IAP measurement, the load on the low back during the patient falls was quantified by a three-dimensional dynamic biomechanical calculation of the torques and the compression at the L4/L5 joint.

Results.
High IAP developed quickly and timed in relation to the external torque when the fighters were exposed to a sudden patient fall. When the trunk load was heavy and sudden, IAP was developed to be present at the time when low-back structures had to cope with the large load.

Conclusions.
High IAP was developed sufficiently fast to be present when the low-back structures had to cope with the large torques released from the sudden trunk loading.