Postoperative Bone Marrow Lesions (BMLs) Are Associated with Pain Severity in Patients Undergoing Open Wedge High Tibial Osteotomy (OWHTO)

The purpose of the study was to investigate the relationship between postoperative bone marrow lesions (BMLs) and pain severity in patients undergoing open wedge high tibial osteotomy (OWHTO). We reviewed the patients undergoing OWHTO between April 2018 and April 2020. The demographic and clinical data of patients were collected. Clinically, VAS and Knee injury and Osteoarthritis Outcome Score (KOOS) were used to assess pain level and functional outcomes of patients. The MRI Osteoarthritis Knee Score (MOAKS) was used to assess the total BMLs size in medial tibiofemoral (MTF), lateral tibiofemoral (LTF), and patellofemoral (PF) joints. 98 patients were enrolled in the study, including 57 male and 41 female patients. The VAS scores improved significantly from 6.1 ± 0.8 to 1.5 ± 0.9 ( p < 0.001 ), and all subscales of KOOS improved significantly after surgery ( p < 0.001 ). There were no significant differences between the pre- and postoperative total BML size of PF and LTF joints ( p > 0.05 ). We observed significant improvements in the total BML size of MTF joint ( p < 0.001 ). The VAS scores and KOOS pain scores improved better in patients without postoperative MTF joint BMLs ( p < 0.001 ). Postoperative MTF joint BMLs were correlated with postoperative VAS ( p < 0.001 ) and KOOS pain ( p < 0.001 ). Our study demonstrates that MTF joint BMLs improved significantly after OWTHO. We confirmed that the presence of postoperative MTF joint BMLs are strongly associated with pain severity. The greater the improvement in postoperative MTF joint BMLs, the less pain. Our findings provide valuable understandings of OWHTO in the treatment of knee osteoarthritis (KOA) and potential future directions for KOA treatment approaches.

Subchondroplasty in the Treatment of Bone Marrow Lesions of the Knee: Preliminary Experience on First 15 Patients

Purpose The aim of this prospective study was to assess the effectiveness in terms of pain relief and functional improvement of the Subchondroplasty procedure in the treatment of osteoarthritis-related bone marrow lesions (BMLs) of the knee. Methods The study included first 15 consecutive patients undergone to Subchondroplasty procedure for the treatment of chronic degenerative BMLs in which previous conservative treatment have failed. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, Knee Injury and Osteoarthritis Outcome Scores (KOOS), and visual analog scale (VAS) pain scores were obtained preoperatively and at 1, 6, and 12 months of follow-up. Results WOMAC scores significantly improved from 39.7 ± 20.2 before surgery to 26.8 ± 16.1 at the 1-month follow-up (p = 0.045). A further significant improvement to 15.5 ± 12.7 (p = 0.02) and to 8.6 ± 3.1 (p < 0.01) was obtained both at 6-month and at 1-year follow-up. KOOS scores improved significantly from 47.5 ± 16.6 before surgery to 65.4 ± 14.9 at 1 month (p = 0.013) and to 80.4 ± 15.1 at 6-month follow-up (p = 0.01). A further improvement to 85.6 ± 15.1 was recorded 1 year postoperatively, although nonsignificant. VAS score showed a significant improvement from 55.8 ± 20.5 preoperatively to 36.2 ± 16.9 at 1 month (p = 0.008) and to 18.2 ± 17.3 at 6-month follow-up (p = 0.005). This further improved to 12.8 ± 17.9 at 1-year follow-up, although not significantly. Conclusion Subchondroplasty procedure represents a safe and valid surgical option in the treatment of osteoarthritis-related BMLs of the knee, providing an improvement in terms of pain relief and functional recovery. Longer studies are required to evaluate how long these improvements may last. Level of Evidence Therapeutic case-series, Level IV study.

Comparison of Clinical and Imaging Outcomes of Different Doses of Adipose-Derived Stromal Vascular Fraction Cell Treatment for Knee Osteoarthritis

Background: Favorable clinical outcomes of the intra-articular injection of adipose-derived stromal vascular fraction (SVF) cells for knee osteoarthritis (OA) have been reported. This study aimed to compare the short-term clinical and imaging outcomes of different doses of SVF cells for knee OA treatment.Methods: This study included 60 patients with knee OA who underwent intra-articular injection of SVF cells. The follow-up period was at least 12 months. The envelope method was used to prospectively quasi-randomized the patients to undergo treatment with different doses of SVF cells. Thirty patients received an intra-articular injection of 2.5×107 SVF cells (low-dose group), and the remaining 30 patients received an intra-articular injection of 5.0×107 SVF cells (high-dose group). Clinical evaluations were performed for range of motion, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and the Knee injury and Osteoarthritis Outcome Score (KOOS). Imaging evaluations, which included the hip-knee-ankle angle and magnetic resonance imaging Osteoarthritis Knee Score (MOAKS) features (bone marrow lesions, cartilage defects, osteophytes, Hoffa’s synovitis, and effusion synovitis), were also performed. All clinical and imaging evaluations were performed preoperatively and 12 months postoperatively and compared between the groups.Results: No significant differences in demographic data were found between the two groups. The knee extension angle at 12 months postoperatively was significantly higher than the preoperative angle in both groups. The total WOMAC and VAS scores at 12 months postoperatively were significantly more favorable than preoperative scores in both groups. The bone marrow lesions and Hoffa’s synovitis and effusion synovitis improved approximately 30-40% from baseline to 12 months postoperatively in both groups. However, there were no significant differences in the preoperative and postoperative results of any clinical or imaging evaluation between the two groups.Conclusions: The short-term clinical and imaging outcomes of intra-articular injection of SVF cells for knee OA were excellent, regardless of whether a low- or high-dose was administered. Intra-articular injection of SVF cells for knee OA is an innovative approach.

The Treatment of Bone Marrow Lesions Associated with Advanced Knee Osteoarthritis: Comparing Intraosseous and Intraarticular Injections with Bone Marrow Concentrate and Platelet Products

Background: Bone marrow lesions are a radiographic indication of bony pathology closely associated with advanced osteoarthritis of the adjacent joint. Injection of autologous orthobiologic products, including bone marrow concentrate and platelet-rich plasma, have demonstrated safety and efficacy in treating both advanced osteoarthritis (via intraarticular injection) and associated bone marrow lesions (via intraosseous injection). The relative efficacy of intraarticular versus intraosseous injection of orthobiologics has not been evaluated at the present time. Objectives: The objective was to evaluate differences in orthobiologic bone marrow lesions treatment, either as a collateral result of intraarticular injection with bone marrow concentrate and platelet products alone, or intraosseous plus intraarticular injection as measured by patient reported outcomes. Study Design: This study employed a prospective case-matched cohort design. Setting: This study took place at a single outpatient interventional orthopedic pain clinic. Methods: Using data from a prospective orthobiologic treatment registry of knee patients, a population of knee osteoarthritis with bone marrow lesions patients who had undergone only intraarticular knee injections of bone marrow concentrate and platelets (for symptomatic advanced osteoarthritis) were age, gender, and disease severity case-matched to a series of advanced osteoarthritis and bone marrow lesions patients who underwent intraosseous plus intraarticular injections. Self-reported patient outcomes for Numeric Pain Scale, International Knee Documentation Committee, lower extremity functional scale, and a modified single assessment numeric evaluation were compared between the 2 treatment groups. Results: Eighty patients were included, 40 in each group. Although pain and functional outcome scores were significantly improved in both treatment groups, there was no statistically significant differences in patient reported outcomes based on the type of treatment. Limitations: There are several limitations to this study, including multiple providers performing the injections, varying onset of symptoms to treatment, and additional injections after their initial treatment, that were not controlled. In addition, increasing the sample size may be beneficial as well, particularly with the large bone marrow lesions group, which did suggest possible improvement with intraosseous plus intraarticular over the intraarticular, although was not statistically significant in our sample. Limited data availability for this cohort as well as some missing data are other limitations to consider. Conclusion: Treating knee bone marrow lesions with intraosseous bone marrow concentrate and platelet products did not affect patient reported outcomes. Key words: Intraosseous, intraarticular, bone marrow concentrate, bone marrow lesion, bone marrow edema, knee osteoarthritis, platelet-rich plasma, injection