Bone marrow lesions in the knee: early results of patients treated with subcondroplasty

Abstract

Introduction: Subchondroplasty is a percutaneous procedure in which calcium phosphate is injected inside BMLs (Bone Marrow Lesions) area under fluoroscopic guidance. The main aim of the present cohort study is to evaluate the effects of subchondroplasty associated to knee arthroscopy in reducing pain and improving in knee function in patients suffering from BMLs located on femoral condyles or tibial plateau. Methods: 30 patients (mean age 65.4 years) were evaluated pre-operatively and at 6 and 12 months after surgery. Numeric pain Rating Scale (NRS), Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), International Knee Documentation Committee (IKDC) were evaluated. Secondarily, edema healing and bone structure were controlled at follow-up by x-ray and MRI. Results: An improvement in all evaluated scores was found at 6 months after surgery compared to the baseline. NRS changed from a mean value of 7 to 1 at 6 months and to 0.86 at 1 year of follow-up, revealing a marked improvement of pain after the procedure (p<0.0001). Furthermore, IKDC and WOMAC scores showed a statistically significant improvement in knee function at 6 months after subchondroplasty (from 26.96 to 70.10 and from 46.87 to 9.00, respectively), which remained stable after 12 months; KSS in every section (objective, satisfaction and function) raised as well during the follow-up. In three cases the treatment failed and a total knee replacement was performed due to persistence of symptoms. Conclusions: Subchondroplasty seems to be safe, reliable and effective in pain reduction and knee function improvements, even though effects at long term still have to be verified.Level of evidence: II, Prospective cohort study Keywords: BML; MRI; STIR; CRPS; SONK.