Analysis Of Posterior Tibial Slope On Short And Medium Term Effect Of Unicompartmental Knee Arthroplasty

Objective:To investigate the relationship between knee function and posterior tibial slope(PTS)after unicompartmental knee arthroplasty(UKA)in the treatment of knee osteoarthritis(OA).Methods:Patients with medial knee osteoarthritis treated with UKA in our hospital from January 2016 to December 2020 were retrospectively analyzed.74 patients(78 knees)were selected according to the inclusion and exclusion criteria,and the follow-up period was at least one year.All patients had informed consent.All patients took positive and lateral X-ray films of the knee joint after operation.The size of postoperative PTS was measured by X-ray.According to the size of PTS,the patients were divided into group A(PTS<3°),group B(PTS 3°～7°)and group C(PTS>7°).The knee side,age,sex,BMI demographic data,HSS,KSS-C,Lysholm,ROM and postoperative knee complications were collected in the three groups.Results:1.All cases were followed up with a median of 2.15 years.There was no significant difference among the three groups in sex,age,knee type,BMI,follow-up time,preoperative KSS-C,HSS,preoperative Lysholm and preoperative ROM(P>0.05).These baseline data were comparable.2.During the last follow-up,the indexes of KSS-C,HSS,Lysholm and ROM in the three groups were significantly improved compared with those before operation(P<0.05).3.After comparing the above indexes among the three groups,there was no significant difference in HSS,Lysholm,ROM and so on(P>0.05).4.There was significant difference in KSS-C score among the three groups(P<0.05).The postoperative KSS-C in group B was significantly higher than that in group A and group C,indicating that PTS could increase KSS-C in the range of 3°～7°,There is a better curative effect after UKA.5.Postoperative complications such as periprosthesis fracture,prosthesis loosening,periprosthesis infection and pad dislocation were not found in the3 groups,and there was no significant difference in the incidence of complications。Conclusions:UKA can obtain significant therapeutic effect in the treatment of simple medial compartment osteoarthritis of knee joint.Too large or too small PTS will result in poor knee joint function.3°～7° PTS is recommended during operation,which can obtain better clinical effect.