There are only a few follow-up studies of untreated Scheuermann’s disease. The aim of this study was to investigate the relationship between vertebral changes, back pain, and disability in patients with untreated Scheuermann’s disease after a 37-year follow-up. Eighty patients responded to a postal questionnaire concerning back pain and disability and 49 of them had classic Scheuermann’s disease. Degree of kyphosis, lordosis, scoliosis, the number of affected vertebrae, and mean and maximum wedge angles were measured from radiographs. Back pain and disability scores were compared to a sample of the general Finnish population (n = 3,835). At follow-up, the patients were on average 59 (SD 8) years old (range 44–79 years), and the mean follow-up time was 37 (SD 7) years (26–54 years). The patients comprised more males than females (3.1:1). At follow-up, male patients were on average 3 cm taller than controls (p = 0.007). At age 20, female patients compared to controls were on average 6 kg heavier (p = 0.016) and had higher body mass index (BMI) (mean 23.9 kg/m2 vs. 20.8 kg/m2, p = 0.001). Scheuermann’s patients had 2.5-fold [odds ratio (OR); 95% confidence interval (CI); 1.4–4.5, p = 0.003] increased risk for constant back pain compared to controls. The risk for disability because of back pain during the past 5 years (OR 2.6; 95% CI 1.4–4.7, p = 0.002), risk for back pain during the past 30 days (OR 3.7; 95% CI 1.9–7.0, p < 0.001) and risk for sciatic pain (OR 2.3; 95% CI 1.3–4.3, p = 0.005) were higher compared to controls. Scheuermann’s patients had higher risk for difficulties in mounting stairs (OR 5.4; 95% CI 2.8–10.3, p < 0.001) and in carrying a 5 kg load for at least 100 m (OR 7.2; 95% CI 3.9–13.3, p < 0.001). Scheuermann’s patients had a higher risk for back pain and disabilities during activities of daily living than controls. However, the degree of thoracic kyphosis among Scheuermann’s patients was not related to back pain, quality of life, or general health.