Posterior fixation of intervertebral discs is used to treat, and occasionally diagnose, discogenic pain since it is thought that it will reduce the internal loading of the discs in vitro. We measured the internal loading of ten intervertebral discs using stress profilometry under simulated physiological loads and then after posterior fixation. Partial discectomies were performed to simulate advanced disc degeneration and the sequence repeated.

Posterior fixation had very little effect on the magnitude of the loads acting on the disc and none when disc degeneration was simulated. It did, however, reduce bulging of the anterior annulus under combined bending and compression (p < 0.03). Recent experiments in vivo have shown that discogenic pain is associated with abnormal bulging of the annulus which suggests that the clinical benefit of fixation may be due to this.

1. A case of compression of the deep branch of the ulnar nerve is described.

2. Anatomical evidence is presented that the reason for the special liability of the deep branch to be compressed by ganglia in this region is its relationship to a ligamentous band which passes from the pisiform bone to the hamate superficial to the deep branch of the ulnar nerve.

3. This band, though constant, has not been well recognised.

1. A case of spontaneous posterior interosseous paresis is reported. It is suggested that the cause was replacement fibrosis secondary to local ischaemic damage from unremembered minor trauma.

2. In a patient with a posterior interosseous nerve paresis examination may reveal a space-occupying lesion near the elbow along the course of the nerve thus compressing it. Recovery may be expected after its removal. Consequently the nerve should be explored before resort to tendon transfers.