Safety, Efficacy and Short-Term Results with Intra-Articular Bone Marrow Concentrate for Arthritic Knee Pain

Objective: Bone marrow concentrate cell procedures have been used frequently over the last decade in the setting of osteoarthritic knee pain and catabolic knee pain syndrome. In this study, safety and therapeutic benefit were assessed for treating knee osteoarthritis using Bone Marrow Concentrate (BMC) with an intra-articular approach. We sought to determine the short-term outcomes of patients treated with this modality over an average ten month follow up period (range 3-36 months) using validated and accurate outcomes assessments including the SF-12, IKDC, LEFS and the visual analogy score for pain. On average, there was improvement in all outcomes analyses over the time period studied. Study patients were uniformly pleased with their outcome and only one patient had gone on to have a total knee replacement during the study period at two years. Two patients with recurrent effusion and pain underwent a Platelet Rich Plasma (PRP) procedure within three months of their BMC procedure. Bone marrow concentrates can provide short-term pain relief in the setting of knee osteoarthritis even when only an intra-articular injection is used. We have modified our treatment algorithm to its seventh generation since 2006 and now include a subchondral injection in addition to intra-articular injection in nearly all patients. In general, those results have been superior to patients receiving intra-articular injection alone. Methods: 94 patients with unicompartmental varus gonarthrosis were treated prospectively. Patients elected to undergo a clinical procedure with intra-articular autologous bone marrow concentrate in the setting of varus gonarthrosis and catabolic osteoarthritic pain syndrome. Patients all failed multimodality conservative treatments before being offered orthopedic immunobiologic treatment with bone marrow concentrate injection. All patients were treated by one surgeon at one facility using the same technique for harvest and injection. Patient related outcome measures (PROMs) were obtained in the pre-operative and post-operative setting at defined time points and included the SF-12, IKDC, LEFS and VAS score for pain. PROMs were compared to determine if there was meaningful improvement in mean clinical outcome metrics from baseline prior to treatment. The frequency and type of adverse events were also examined. Results: No serious adverse events were reported with treatment in any patient. There was meaningful improvement in mean clinical outcome metrics from baseline in all patients during the time period studied. Mean change in visual analog scale exceeded the published minimum clinically important difference of 2.5 (3.4). The Lower Extremity Functional Scale mean change was +20 which exceeds a published 9 point minimum clinically important difference. The IKDC score mean change was +17 which exceeds a published 8 point minimum clinically important difference. Differences from baseline to follow up in the SF-12 demonstrated improvement in both the physical component (+9) and to a lesser degree the mental component (+2). The mean change in the physical component of the SF-12 exceeded the published minimally clinically important difference of 3.77. Conclusion: Safety was demonstrated for bone marrow aspiration and concentration from the anterior gluteal pillar followed by a bone marrow concentrate procedure via an intra-articular route of administration in patients with isolated, unicompartmental varus gonarthrosis with Kellgren-Lawrence 2-3 knee osteoarthritis. Mean changes at 10 weeks showed substantial improvement from baseline in the clinical outcome metrics with VAS, IKDC, LEFS and SF-12 all exceeding published minimal clinical important difference values. Patients were satisfied with a bone marrow concentrate procedure for osteoarthritic knee pain during this short term follow up period.