Aim To identify degenerative knee abnormalities using MRI and radiography 6 years after knee trauma, their relation with persistent knee symptoms and baseline prognostic factors.

Methods Adults (18–65 years) with incident traumatic knee symptoms visiting their general practitioner were followed up for 6 years and underwent baseline MRI and 6-year follow-up MRI and radiography. Logistic regression was used to analyse associations between various degenerative abnormalities on 6-year MRI and radiography, persistent knee symptoms and baseline prognostic factors for knee osteoarthritis (OA) on 6-year MRI.

Results On 6-year radiography, 60% of patients showed no OA, 28% showed OA with Kellgren&Lawrence (K&L) grade 1 and 13% showed with K&L grade 2. On 6-year MRI, 55% of patients showed cartilage defect(s), 45% showed osteophyte(s), 36% showed subchondral cyst(s), 40% showed bone marrow oedema, 21% showed meniscal subluxation, 83% showed meniscal degeneration,11% showed effusion and 11% showed a Baker's cyst. Of these, most were significantly related with 6-year radiographic K&L grade, while only lateral cartilage defect(s), medial osteophyte(s) and medial meniscal subluxation were significantly related with persistent knee symptoms. 32% of patients showed new onset or progressive knee OA on 6-year MRI, for which age, history of non-traumatic knee symptoms and bone marrow oedema at baseline were independent prognostic factors.

Conclusions Degenerative knee abnormalities on MRI are related to the K&L score; however, not all abnormalities are reflected in clinical outcome. Age, history of non-traumatic knee symptoms and bone marrow oedema predict knee OA 6 years after knee trauma, present in 32% of the patients.