Objectives To compare between the uses and side effects of MRI and myelography for the diagnosis of PID, and to assess the relation between PID and joint mobility.

Methods One hundred thirty patients with PID proved by MRI (65) on myelography (65) were compared with that in an age and sex matched healthy 130 individuals without PID joint mobility was scored on a scale of 0–8 using the method described by Reighton et al.

Results PID was commonly reported at L4/5 or L5/S1 levels, whilst other levels were less frequently involved. Both imaging modalities were highly sensitive to prove the diagnosis of PID and its level, unfortunately myelography showed significantly more side effects compared to MRI.

The number of patients with hypermobile joints and the total mobility scores were comparable in patients and control groups.

Conclusion This study showed that both imaging modalities are sensitive for diagnosis of PID, and MRI is a safer technique compared to myelography. There is no relation between PID and joint mobility.