The effect of systemic methylsulphonylmethane on the post-traumatic arthritis in rats applied with traumatic ankle model

Post-traumatic ankle osteoarthritis (PTAO) is clinically manifested by intra-articular incompatibility of the ankle that causes severe ankle and adjacent joint morbidity. In this experimental study, it was aimed to compare the treatment efficacy of previously tried and still applied intra-articular injections and oral Methylsulfonylmethane (MSM) at functional and histopathological level in PTAO animal model. 32 adult female Sprague-Dawley rats were included in the study. The subjects were divided into 4 groups (Group 1: Control, Group 2: 0,06g/kg/day MSM, Group 3: 0,04 mg/ µL Methylprednisolone (MP), Group 4: 0,04 mg/ µL Hyaluronic Acid (HA)). PTAO model was created by applying right ankle medial malleolar osteotomy to all subjects. MSM was started to apply orally daily between day 0 to the end of 8 weeks. Intra-articular injections (MP and HA) were applied to the right ankles of the subject's 2nd,3rd and in the 4th week after surgery. All subjects were sacrificed after radiological evaluation at the 8th week. Subsequently, functional (range of motion) and histopathological evaluation was performed. Radiological evaluation showed that statistically significant better results of the MP (p<0,001) and MSM (p<0,001) groups than the control group. In addition, severity of osteoarthritis in the MP group was significantly less than in the HA group (p=0,032). When evaluated histopathologically, the increase in vascularity (p<0,001) and focal cell loss (p<0,001) in the MP and HA group is remarkable compared to the other groups. When the total OARSI score was compared, it was found that the severity of osteoarthritis was higher in the MP and HA groups than in the control group (p<0,001). No significant statistical difference was found in the histopathological comparison of MSM and control group (p=0,466). When we compared all groups, there was no statistical difference between the groups in both dorsi-flexion (p=0,103) and plantar-flexion (p=0,771) measurement differences according to the contralateral ankle joint. The radiological progression of osteoarthritis was slowed in the MSM and MP groups, but significant histopathological worsening was found in the MP and HA applied groups. In conclusion, the data obtained from this study suggest that the treatment methods used in daily practice may need to be reviewed.