Introduction and purpose: An analysis was made of the patients’ clinical and radiographical evolution after surgical treatment of osteochondritis dissecans of the knee (ODK) by means of reinsertion, abscission and an osseocartilaginous autograft. An assessment of prognostic factors was also performed.

Materials and methods: Retrospective revision of 30 patients (mean age: 30 years), 5 of them with bilateral involvement. A reinsertion of the fragment was performed in 11 knees, an abscission was used in 18 and an autograft in 6. A clinical assessment using Hughston’s criteria and SF12 was carried out; a radiographical evaluation was also performed using weight-bearing A/P views with the knee flexed 45°. Using the variance analysis test, a study was made of the relationship between clinical status, age, localization, extension, stability, type of treatment, timescale of evolution and degree of joint impingement. The average evolution was 19 years.

Results: Pain was reported as mild or nonexistent by 75, 50 and 21% of patients treated with reinsertion, abscission and grafting respectively. The higher the degree of joint impingement, the worse the patients’ pain level and their joint balance. At the time of treatment, the highest degrees of joint impingement were found in older patients, in lesions in weight-bearing areas, lesions with an intraarticular free fragment, lesions treated with grafting and those with over 15 years’ evolution.

Conclusions: Osteoarthritic changes are frequent after surgical treatment of osteochondritis dissecans, especially in lesions situated in weight-bearing areas. The more joint impingement there is, the worse the expected clinical prognosis. We recommend early treatment of symptomatic lesions and the reinsertion of the osteochondral fragment.