Abstract: Objective To investigate the mid-and long-term effect of arthroscopic percutaneous internal fixation for the treatment of tibial plateau fractures. Methods 31 patients with tibial plateau fractures treated by arthroscopic percutaneous internal fixation from May 2005 to May 2015 were followed up for a minimum of 3 years.The Lysholm score,Tegner motor level score,Rasmussen functional score,Rasmussen radiological score and Ahlback osteoarthritis classification of the knee joints were recorded at 6 months and the last follow-up. Results  Bone union was achieved in all patients,and no nonunion or malunion occurred.There were 3 cases of stiffness of knee joint after operation,2 cases of them were improved after physiotherapy combined with rehabilitation exercise,1 case underwent arthroscopic soft tissue release after 6 months of operation to confirm fracture healing,and the range of motion of knee joint was satisfactory after operation.All  patients were followed up,with a minimum follow-up of 3 years and an average followup time of (56.90±17.03) months.There was no significant difference in Lysholm score,Tegner score and Rasmussen score between the last followup and 6 months after operation in all patients(P＞0.05).At the last follow-up,the knee flexion and extension were (132.06±4.89)° and 1.55±2.84)°,respectively.There was significant difference in Rasmussen radiological score of knee joint and Ahlback osteoarthritis classification between the last follow-up and 6 months after operation(P＜0.05).Compared the affected side with the healthy side on the full-length weight-bearing X-ray film of lower extremity,it was found that the average rotation angle of the axial force line of lower extremity was significantly different between the last follow-up and 6 months after operation(P＜0.05).At the last follow-up,among the 31 patients,6 had valgus deflection and 2 had varus deflection.Age and intra-articular soft tissue injury were factors for osteoarthritis(P＜0.05). Conclusion For patients who received arthroscopic percutaneous reduction and internal fixation for lateral tibial plateau fractures,the Lysholm score,Tegner score and Rasmussen score in the mid-and long-term follow-up after the operation showed that the overall function of the knee joint was satisfactory.The incidence of arthritis was lower than that reported in the literature for those receiving open reduction and internal fixation,and the curative effect was not good enough for patients who were older(＞50 years) and those with fractures combined with intra-articular soft tissue injuries.

Key words: tibial plateau fracture, arthroscopy, internal fixation, closed reduction, lysholm scoring system, Tegner scoring system, Rasmussen scoring system