Invalidity pension after lumbar disc operation

A total of 753 patients (328 women, 425 men) below 65 years of age and without previous pension living in the South-West of Finland, were operated on for the first time for lumbar disc herniation during the period 1975-1979. The frequency of a new invalidity pension was observed during a follow up period of two years. Of the 753 patients there were 100 new invalidity pensioners (13%) during one year and 133 (18%) during two years after the first operation. According to a statistical model for the impact of age and nature of work on invalidity pension the greatest risk of pensioning for women was associated with age, pensioning being more than five times higher in the age group 45-54 years than below 35 years. Moderate and heavy work by women constituted a minor risk factor, increasing the risk by less than two times compared with light work. In men the risk correlated clearly to both age and nature of work. Moderate and heavy work increased the risk nearly three times compared with light work. The frequency of pensions among 45-64 year old men was even 6-8 times higher, than the risk for men below 35 years. A second operation increased the risk on average two to three times. Cauda equina syndrome was not a risk factor for receiving an invalidity pension. The primary diagnosis for an invalidity pension was something other than lumbar disc herniation in 20%. Patients with unsatisfactory results after lumbar disc operations account for about 10% of all the new invalidity pensions due to some form of back disease in Finland.