Objective: To investigate the effectiveness of cryotherapy on pain and physical function in knee osteoarthritis. Data sources: An electronic search was performed up to February 2019 on PubMed/MEDLINE, EMBASE, CINAHL, Lilacs, Cochrane, Web of Science, Ibecs, and Scielo databases with keywords knee osteoarthritis and cryotherapy. Methods: Two authors independently performed the study selection. All languages and publication dates were considered. The PEDro scale was used to assess the methodological quality of the studies, and the body of evidence was analyzed and synthesized using the Grading of Recommendations, Assessment, Development, and Evaluation approach. The clinical relevance of the included studies was evaluated using the criteria proposed in the Cochrane Handbook for Systematic Reviews of Interventions. Results: Of the five studies, 202 subjects were included. All studies included participants with established knee osteoarthritis. The mean PEDro score was 4.20/10, and meta-analysis was not possible due to heterogeneity among the studies. The mean clinical relevance was 3/5. Only two studies were considered for analysis based on the GRADE approach, and low level of evidence was synthesized regarding the effectiveness of cryotherapy for pain management, knee stiffness, knee range of motion, and physical function. Application techniques, frequency, and duration did not affect outcomes. Conclusions: There were insufficient primary studies to draw any conclusions about the effectiveness of cryotherapy on pain and physical function on individuals with knee osteoarthritis.

Methods: Male, ten week old C57Bl/6 mice (n¼91) underwent a sham surgery (n¼15) or modified PMM surgery (n¼76) in the left hind limb. Three and six weeks post-injury 5x10 5 hUC-MSCs (isolated from three individual UC donors, Donors 1-3) were injected intra-articularly and joints were harvested eight and twelve weeks post-injury, respectively. Sham groups and PMM controls (both receiving no cells) were included at both time points. Histomorphometric analyses of the knee joints were obtained using micro-computed tomography (m-CT) and the OARSI semi-quantitative scoring system was used to assess the histopathology throughout the knee joint on safranin-O and fast green stained sections (minimum of 8 sections per knee, 10mm apart). These were scored by three scorers, to yield a max score (0-6) for each of the four joint quadrants (medial femoral condyle (MFC), medial tibial plateau (MTP), lateral femoral condyle (LFC) and lateral tibial plateau (LTP) throughout the knee joint. A summed score (0-72, where a higher score signifies increased joint degeneration) was also obtained from the highest three scoring sections per knee. Synovitis was also scored by three scorers, on one H&E-stained section midway through the joint. The inflammatory markers, interleukin 6 (IL-6), IL-1beta, IL-4, IL-10, interferon-gamma (IFN-y), monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor-alpha (TNF-a) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were analysed using custom mesoscale discovery (MSD) biomarker assays in murine plasma at the 12week time point. Results: Micro-CT analysis revealed osteoarthritic changes in all the PMM joints, with joint space narrowing and osteophyte formation. The median joint space following PMM on the medial side in the control group was significantly less than in the sham operated knees at eight weeks (PMM¼4.5mm, sham¼42.8mm; p¼0.02) and at 12 weeks (PMM¼0mm; sham¼51.8mm; p¼0.0003). The injection of hUC-MSCs from the three cord donors resulted in variable outcomes in the treated mice. PMMoperated mice (n¼8 at 12 weeks) that received hUC-MSCs from Donor 1 had a significantly (p¼0.02) preserved joint space compared with the PMM control; this significance was not seen at 8 weeks, whereas Donors 2 and 3 showed no significance at either time point. All PMM treatment groups had a greater number of osteophytes than sham operated knees at the 8 week time point, whilst at 12 weeks, only joints that received hUC-MSCs from Donor 3 and the PMM control had significantly more osteophytes than the sham control. Hence Donors 1 and 2 showed no significant difference to the sham control. There were only minimal changes observed in the epiphyseal subchondral bone thickness and bone:total volume at both time points across all treatment groups. All PMM groups (with and without implantation of hUC-MSCs) had a significantly higher (worse) summed joint score than the sham control at 8 weeks, but there was no significant difference at 12 weeks. When looking at the maximum scores for the medial vs the l...