Physiotherapists in Llanelli treat many different conditions including the issues profiled below.

Sudden Loads On Lumbar Discs

In experiments on lumbar spines from cadavers the commonest way a disc will fail is if it is placed in significant bending and compressed quickly is to form a prolapse at the rear of the disc. Prolapse occurred most easily in discs which had not degenerated but were between forty and fifty years old. It was not possible to make a very degenerated disc prolapse. The angle of bend or the compressive forces do not need to be excessive as if one of them is over the normal limits it can generate a prolapse. Prolapses mirrored what people say as they occurred with an audible popping sound and occurred suddenly.

Typically a complete split appeared in the rear part of the disc wall and through this fissure the internal nuclear material prolapsed. The prolapse either occurred at one corner of the back of the disc (a common finding in people with disc problems) or more centrally where the nearby ligament prevented it from moving out further. Disc prolapse occurs mostly in discs with some weakening of the disc wall fibres yet a reasonably good nucleus which can respond to the forces by generating high pressures. Degenerated discs did not prolapse on testing.

Repeated Loading of Lumbar Discs

Lower loads than the sudden compression loading which occurs seldom can cause a disc prolapse if the loading in a bent position is repeated in a cyclical manner. This can be caused in discs which are reasonably young and causes a large split in the rear of the disc wall to one side or another, allowing the central nuclear material to ooze out. In several examples the layers of the disc wall which were the most outer ones did not split and form a fissure and the nuclear material protruding through the fissure inside built up behind the remaining layers in a bulge. As the ligament overlying this has many nerve endings, such a bulge could cause pain.

Older discs were shown in some cases to have fissures which are already present before any experimental loading and these discs did not prolapse during the loading tests, perhaps because the fissures had healed or because discs in poorer condition are too stiff and fibrosed to prolapse. If twisting, side bending or compression is added to bending then prolapse can occur more easily with less bend of the back. In some cases the nucleus may protrude out but in others the outer disc walls can protrude themselves.