| Objective: The medial open wedge high tibial osteotomy(MOWHTO)for the treatment of medial compartment osteoarthritis with varus deformity of the knee joint can achieve satisfactory results in general,and achieve its therapeutic purpose by adjusting the distribution of lower limb force line in the coronal plane of the knee joint.However,the change of the sagittal tibial posterior slope(PTS)is not what we expected.Although the change of PTS after surgery has attracted more and more scholars’ attention,there is still some controversy about the relevant factors that may affect it.This study aims to analyze and explore the relevant factors that may be related to the change of PTS after MOWHTO for reference in clinical work.Methods: According to the relevant inclusion and exclusion criteria,the data of 35 patients with 37 knee joints treated by MOWHTO in our department from October 2019 to July 2020 were collected.The correlation between PTS changes and general information,hinge point position,tibial width,osteotomy depth,degree of correction,position of force line,as well as the proximal medial angle of tibia,included angle of lower limb mechanical axis,patella height,joint line inclination,joint line convergence angle and postoperative knee joint function score before and after surgery was analyzed,and then the independent influencing factors related to PTS changes were found through stepwise regression analysis.Results:The general data of 35 patients showed that there were 11 males and 24 females;The average age was(56.73 ± 6.53)years;19 cases(51.4%) on the left side and 18 cases(48.6%)on the right side;Body mass index(27.48 ± 3.31)kg/m2;K-L grading: Grade II 8(21.6%)cases,Grade III29(78.4%)cases;The operation duration was(140.81 ± 18.99)min,and the intraoperative bleeding volume was(48.65 ± 39.92)ml;The follow-up time was(23.95 ± 5.20)months.The knee joint function score of patients improved significantly before operation and at the last follow-up(P<0.01).The PTS of 37 cases of knee joint was(8.50 ± 4.11)° before operation and(6.42 ± 4.90)° after operation,and the change of PTS was(-2.08 ± 5.23)° after operation;The three met the normal distribution,and the difference was statistically significant before and after surgery(T=2.426,P=0.020).The results of correlation analysis between PTS change and parameters such as tibial width,proximal medial angle of tibia,included angle of lower limb mechanical axis,and functional score showed that it was positively correlated with the actual correction degree(r=0.436,P=0.007),with tibial width(r=0.388,P=0.018),with osteotomy depth(r=0.411,P=0.012),and with patellar height change(r=0.441,P=0.006),There was no significant correlation between other relevant parameters and the change of PTS(P>0.05).Stepwise regression analysis was used to find independent influencing factors.The results showed that the actual correction degree,osteotomy depth and patellar height were independent influencing factors of PTS change,while tibial width was not independent influencing factor.In addition,all patients had no complications of lateral cortical fracture and poor union of osteotomy end.Conclusion: This study mainly found that there was a significant positive correlation between the actual correction degree,osteotomy depth and patellar height changes during the operation and the changes in the early postoperative tibial posterior angle,that is,the greater the actual correction degree,osteotomy depth and patellar height changes,the more obvious the changes in the tibial posterior angle will be.Surgeons should be alert to the possible changes in the posterior inclination of the tibia,especially in combination with the above high-risk situations. |
PDF Full Text Request