MAIN OBJECTIVETo evaluate the short- and long-term effectiveness and safety of corticosteroid injections.DESIGNDescriptive, prospective study.LOCATIONUrban general practice centre.PARTICIPANTSAdult patients (age>18 years) who experienced failure of medical treatment and reported pain scores ≥4 on the Visual Analogue Scale (VAS).INTERVENTIONSPatients received injections of triamcinolone acetonide, maximum 3injections.MAIN MEASUREMENTSShort-term success was defined as a reduction of ≥3 points on the VAS. Long-term success was defined as the absence of symptom recurrence at 6, 12, 18, and 24 months, with an assessment of any complications.RESULTSA total of 345 corticosteroid injections were administered. Patient's mean age was 58.8 years, and 73% were women. The most common conditions treated included rotator cuff disorders (38.3%), plantar fasciitis (16.5%), trochanteric bursitis (15.7%), epicondylitis (11.6%), and anserine bursitis (9.6%). 78.6% of injections were successful short term, with an average VAS reduction of 4.4 points (95% CI: 4.1-4.7). For the primary conditions, the VAS reduction exceeded 4 points. Long-term success rates were 73.3% at 6 months, 64.6% at 12 months, 60.6% at 18 months, and 56.5% at 24 months (P<0.001). At 24 months, the success rates were: rotator cuff disorders (49.2%), plantar fasciitis (49.1%), trochanteric bursitis (66.7%), epicondylitis (47.5%), and anserine bursitis (84.8%). The overall complication rate was 1.2%, all being minor.CONCLUSIONSCorticosteroid injections are highly effective and safe for managing osteoarticular conditions short term. However, the effectiveness declines progressively over 2years, with outcomes varying depending on the specific pathology.