A prospective survey of the causes of non-traumatic spastic paraparesis and tetraparesis in 585 patients.

OBJECTIVE: To ascertain the relative frequencies of the causes of non-traumatic paraparesis and tetraparesis in adults.

DESIGN: Survey of patients enrolled prospectively over a 3 year period between 1986 and 1989 and review of their case notes 1 year after enrollment ceased (mean duration of follow up 30 months).

SETTING: Regional neurosciences centre in the UK serving over three million people in Merseyside and North Wales.

PATIENTS: Experienced clinicians from the centre saw most patients in the region with non-traumatic spastic paraparesis or tetraparesis. Primary investigation of patients was by myelography, for which patients were admitted to the centre. 585 consecutive patients with spastic paraparesis or tetraparesis were identified by daily screening of all 2104 patients undergoing myelography or radiculography during the 3 year period, ie selection by the intention to investigate them for myelopathy.

EXCLUSIONS: age under 15 years, previous myelography for myelopathy.

INTERVENTIONS: None.

MAIN OUTCOME MEASURES: Numbers and proportions of patients with each condition or category of disease.

RESULTS: Commonest diagnoses were cervical spondylotic myelopathy (23.6%), extrinsic neoplastic or developmental tumour (16.4%), multiple sclerosis (9.1% rising to 17.8% after MRI of a selected group), and motor neurone disease (4.1%). Diagnosis was uncertain in 27.4%, falling to 18.6% after MRI.

CONCLUSIONS: This survey shows the pattern of diseases producing non-traumatic myelopathy in the Mersey Region and in North Wales. Changing patterns of referral, investigation in peripheral hospitals and by non neurologically trained practitioners, and increasing use of outpatient MRI for primary investigation may make comparable surveys impossible in the future.