BMAC/ Stem cell therapy has opened a new horizon in the treatment of KOA and may in future shift the paradigm in the clinical practice. Stem cell research arose from the need to explore the new therapeutic possibilities for Orthopaedic related problems [Granero Molto et al, 2008, Davatchi.F et al, 2011]. BMAC/Stem cell therapy can be applied to the problems related to bone, cartilage and tendon regeneration. In the Orthopedics field, for the diseases which current treatment modalities do not offer satisfactory, efficient or durable results may be targets of stem cell treatment [Sampson et al, 2015]. BMAC/Stem cell treatment may provide an innovative, cost effective and reliable therapy for knee osteoarthritis [Im 2016; Vanatier et al 2009].
During the recent years there is an increasing interest in using intra articular BMAC injection in the treatment of KOA. BMAC is essentially a combination of cellular component, soluble growth factors and cytokines. The cellular component of BMAC contains various MSCs, haemopoietic precursors, monocytes and endothelial cells. BMSCs exhibit immune modulatory, anti-inflammatory, proliferative and chemo attractive functions. Therefore, BMACs can induce the differentiation process of cellular regeneration in the osteoarthritis knee joint. Various growth factors present in BMAC like TGF beta, VEGF, BMP2, IL 1ra and platelet derived growth factors work on the various cellular pathways essential in the regulation of cell catabolic and pathways [Cavallo C et al, 2020].
Therefore, the combination of cellular component and various biologically active proteins makes BMAC a unique orthobiological treatment modality by not only reducing the pain in KOA, but also has the potential to alter the disease progress.
The advantages of BMAC are ease of obtainability (aspiration from iliac crest), no need for culture and cell expansion, no or reduced risk of infection (point of source processing and injection) and no risk of allogeneic disease. With all these advantages the usage of BMAC as a treatment modality in KOA is rapidly growing and gaining popularity [Cavallo C et al, 2020].
Earlier studies showed good results, where the bone marrow stem cells were used in Knee Osteoarthritis (Tibiofemoral and patellofemoral joints) and isolated osteochondral lesions, with a follow up of 12–24 months [Wakitani et al, 2007; Kuroda et al, 2007; Haleem et al, 2010; Kasemijwattana et al, 2011; Giannini et al, 2009; Giannini et al, 2010; Gobbi et al,2011; de Windt et al, 2016]. Latest studies in the literature have uniformly emphasized on the safety and benefit of intrarticular injection of autologous BMAC in KOA [Mautner, 2019; Cavallo C et al, 2020].
In the current study, single injection of intraarticular autologous BMAC (rich in BMSCs) was administered into the KOA joints in 132 patients (KL grade II and III) and evaluated the functional and clinical results both objectively and subjectively for a period of 12 months. We found that there is a uniform improvement of pain score and activity of daily living (quality of life) following the BMAC injection and sustained relief of pain even at the end of 12 months in 125 patients. In 7 patients with KL grade III, persistence of knee pain with high demand activities like stairs climbing and squatting needing to use occasional COX2 inhibitors for pain relief.
10 patients out of 132 (13%) showed increased knee joint space and improved KL grade from 3 to 2 in Post BMAC injection weight bearing knee radiographs at the end of 12th month as compared to pre injection radiographs (Fig. 7). Rest of the patients remained in the same KL grades. In 10 patients, the follow up knee MRI at the end of 12th month, there is an increased cartilage volume (20 to 30%) of the knee was also observed. No adverse events were observed in any of the patients following BMAC injection. Therefore, the current study showed both subjective and objective improvement in all the patients following single intrarticular autologous BMAC injection in KL grade II and KL grade III KOA patients.
Other studies from the literature, Shapiro, 2016; Garay-mendoa, 2018; Mautner, 2019; also conducted BMAC injection for KOA patients however, our study duration follow up was long i.e 12 months whereas other studies followed up till 6 months. Recent study of Anz et al, 2020 was almost similar, but in the current study both subjective assessment by VAS and WOMAC scores was done for the period of 12 months and objective assessment by X- rays and MRI was novel feature of our study.
4.1. The unique features / highlights of the current study:
We recruited KOA patients with KL grade II & III as compared to KL grade I&II in most of the studies in the literature. The number of patients was equal in both KL grades groups. We have given a single injection of autologous BMAC harvested from iliac crest. Post injection all patients were followed both subjectively and objectively with weight bearing knee radiographs and in 30% of patients Knee MRI was done to know the cartilage volume, where as in most of the studies only subjective assessment of post injection results was done.