ADJUVANT TREATMENT OF OCD LESIONS OF THE KNEE WITH BONE STIMULATORS

BACKGROUND: Recently, bone stimulators have been increasingly used for fracture care, particularly in the context of delayed healing and nonunions. Bone stimulation provides upregulation of osteogenic factors and stimulation of osteoblasts to create new bone. HYPOTHESIS/PURPOSE: The purpose of this study was to determine if adjuvant use of bone stimulation would improve the rate of healing in the operative management of stable osteochondritis dissecans (OCD) of the knee. Methods: Forty patients who presented with a stable OCD lesion of the knee were included in the present retrospective study. All patients were managed with operative intervention with anterograde drilling by a single senior surgeon. The patients in the two groups, those with or without the use of bone stimulators post-operatively, were matched for skeletal maturity, lesion location, gender and age at surgery. The primary outcome measure of the rate of healing was determined from 3 month post-operative MRIs and clinical results were also analyzed. RESULTS: At two years, 36 patients (90%) in both groups went on to clinical healing without further interventions. Two patients in each group required re-operations. The bone stimulator group had a mean decrease of 0.9 (± 1.8) mm in lesion coronal width and had 12 patients (63%) who had overall improved healing as compared to the non-bone stimulator group which had a 0.8 (± 3.6) mm decrease in coronal width and 14 patients (78%) with improved healing (p=0.272). No statistical differences in imaging or clinical healing were found between the two groups. Male patients were seen to have a clinically important decreased time from surgery to sports clearance (4 versus 5.5 months, p=0.063), discharge (7.8 versus 13.4 months, p=0.057), and increased overall healing (81% versus 55%, p=0.187) as compared to females. Skeletally immature patients had a decreased time from surgery to discharge (7.0 versus 18.3 months, p=0.005), improved overall healing (79% versus 50%, p=0.158), and decreased reoperation rate (3% versus 30%, p=0.042) when compared to the skeletally mature patients. CONCLUSION: In the surgical treatment of stable knee OCD lesions, bone stimulator use did not appear to improve radiographic or clinical healing. However, this study was not powered to examine the clinically important differences between the patients with and without the use of bone stimulators. Further multi-institutional studies will be needed to further elucidate differences. This study did find that skeletally immature patients had improved outcomes both clinically and on imaging as compared to skeletally mature patients.