Effect Of Posterior Cruciate Ligament Retaining Or Not On Early Clinical Efficacy Of Primary Total Knee Arthroplasty

Background: With the society aging and the numbers of old people increasing,the incidence rate of knee osteoarthritis(OA)rises year by year.Total Knee Arthroplasty(TKA)has become an effective therapeutic method for most of the patients with advanced knee osteoarthritis.There is a great debate about posterior cruciate-retaining total knee prostheses(CR)and posterior cruciate-stabilizing total knee prostheses(PS),since the modern knee prostheses has been used in 1970 s.PS has become a mainstream design and option.PS will reduce patient's proprioception and be poorer in stairs after TKA,while CR will be more in line with knee joint anatomical characteristics.CR is more similar to the nature knee,and much better to restore the knee joint normal physiological mechanism.The gait of knee joint after TKA is near normal,as the knee proprioception and normal femur rollback are retained in CR.CR and PS have been developed for 30 years,but the debate over whether to retain posterior cruciate ligament is still hot.In this study,short-term follow-up was performed on the clinical efficacy of CR prostheses and PS prostheses for the primary total knee arthroplasty,in order to analyze the effect of the posterior cruciate ligament(PCL)retaining or not on clinical efficacy by comparing the efficacy difference between PCL retaining and no PCL retaining.Objective: The short-term follow-up was performed on the patients with knee osteoarthritis for primary total knee arthroplasty.In order to compare the effect of the PCL retaining or not on early clinical efficacy by analyzing the difference of the two kinds of prostheses on perioperative blood loss,knee maximum flexion,knee scores,patient satisfaction and proprioception.Methods: 60 patients(60 knees),who were treated by total knee arthroplasty(TKA)from January to October 2016,were included in this retrospective study.They are from 60 to 80 years old,and their average age is(66.5±6.8)years.There are 30 patients(26 female,4 male),who take the posterior cruciate-retaining prostheses(Group CR).Their body mass index(BMI)is(24.7±2.8)kg/?,and there are 18 left knees and 12 right knees.There are 30 patients(25 female,5 male),who take the posterior cruciate-stabilizing protheses(Group PS).Their body BMI is(22.5±3.2)kg/?,and there are 20 left knees and 10 right knees.There are no statistics difference at the average ages,gender and BMI of those patients in two groups.Both CR and PS prostheses are produced by Smith & Nephew Company.All those patients with surgery were completed by the same surgeon as the stadard TKA technique,and were not patellar resurfacing.All of the surgeries were performed via anterior knee median incision and medial parapatellar tendon approach.Wound drains were placed when the surgery were finished,and let patients do postoperative functional exercise.The author analysis the difference on the amount of blood loss,knee maximum flexion,WOMAC,HSS score and patient satisfation(Using the Brithsh Orthopaedic Association patients satisfaction score)after CR or PS total knee arthroplasty.In order to document the proprioceptive capabilities of the knees,patients were asked to evaluate the joint position sense(JPS)by the continuous passive motion.Results: Both of the general information containing age,gender distribution and BMI and prooperative clinical data containing WOMAC score and HSS score have no statistical different.All 60 patients treated by TKA with CR and PS total knee prostheses were followed up for 6-10 months,averaged(8.14±1.25)months.The incisions of all the patients in both groups achieved healing of incision by first intention,without infection,periprosthetic fractures and re-operation.Group CR was followed up for(8.20±2.05)months,while Group PS duration was(8.08±1.55)months.All the patients took the blood routine examination on the third day,the hemoglobin consistency decreased at(21.35±7.21)g/L in Group CR while it decreased at(23.21±6.52)g/L in Group PS,there's statistical significance within and between groups(P<0.05).At final follow-up,the maximum flexion in CR was(120±2.52)°,while the PS was(122±3.58)°,P<0.05.WOMAC and HSS Scores were applied in the review.WOMAC Score was decreased to 9.19±1.22 from the preoperative 48.67±3.26,and HSS Score was increased to 92.11±3.61 from the preoperative 63.26±4.13 in Group CR.In Group PS,WOMAC Score was 46.93±4.65 preoperatively and decreased to 10.21±2.51,and HSS Score was 62.58±3.91 increased to 91.60±3.25 at final follow-up.There was statistical significance before and after operation(P<0.05),while no significance between the two groups(P>0.05).Compared to the prioperation,the knee pain score,function score and the range of motion score have statistical significance at final follow-up.The range of motion score was increased to 14.28±1.38 from the properative 10.60±2.05 in Group CR,while it was increased to 14.66±1.58 from 10.21±2.57.There's statistical significance within and between groups.The patients satisfaction score was 3.56±0.18 in Group CR,while 3.10±0.37 in Group PS,there was statistical significance between two groups(P<0.05).There was significant difference in JPS 30°,JPS 45°and JPS 60°before and after operation(P<0.05).The absolute error of angle in Group CR was smaller than PS(P<0.05).Conclusion: The amount of blood loss of the patients who choose the CR is less than the patients who choose PS in perioperative period,and the CR prostheses has more advantages on proprioception,but the PS prostheses is better on the knee flexion.There was no significant difference between the two kinds of prostheses on early Knee Scores after total knee arthroplasty,but both of their scores were imprived by comparing to the perioperative score.Both of them hava a good postoperative clinical efficacy,and the patients satisfaction score was higher in Group CR.