Application Research Of Improved Gap Balancing Technique In Total Knee Arthroplasty

BackgroundTotal knee arthroplasty(TKA)is a definite and effective surgical procedure for the treatment of knee osteoarthritis at the end of its onset.The operation can effectively correct the deviated lower limb force line and reconstruct the biomechanical structure of the knee joint.At present,the most commonly used surgical techniques all around world include measure resection technique,gap balancing technique and hybrid.The imbalance of soft tissue tension around the knee joint prosthesis at equal intervals is one of the main reasons affecting its survival rate.It will directly lead to accelerated wear and loosening of the prosthesis,joint instability and shortened the survival time of the prosthesis.Obviously,it is very important to get the balance of space and pressure between bone structure and surrounding soft tissue.ObjectiveA systematic review of the literature on primary knee arthroplasty with gap balancing technique as the core in the treatment of knee osteoarthritis was made to clarify the biomechanics and kinematic anatomy of the knee joint,the historical development of the technique,its application principle,advantages and disadvantages,and the comparative results with the measurement resection technique.And the clinical application and effect of knee arthroplasty assisted by knee joint space distraction with pressure tester were evaluated.MethodsFrom August 2017 to August 2018,40 patients with knee osteoarthritis requiring total knee arthroplasty were selected.The experimental group and the control group were set up after unified inclusion criteria(age 58-70 years old,varus deformity and medial tibial plateau defect<3mm,Varus deformity of knee joint?15°,BMI?30kg/m~2,fixed operatos and prosthesis).The experimental group was operated with the help of the knee joint space distraction with pressure tester.The control group was operated by measure resection technique.The tightness and matching of prosthesis installation during operation were compared,and the imaging and related functional scores after operation were compared and analyzed.ResultsThe study found that the two groups of patients included in this study,whether using improved gap balancing technology or measure resction technology to complete a total knee arthroplasty,the operation time is basically the same,there is no significant difference.For mild flexion contracture varus deformity,no specific bone structure loss or variation,the results of lower limb force line correction,size matching of knee prosthesis,angulation measurement during femoral prosthesis rotation,patellar trajectory correction,patellofemoral joint fitness and knee joint range of motion(ROM)of the two groups can obtain similar objective values.Postoperative radiographs of knee joint in the position of extension,valgus and varus stress showed that the opening distance between the medial and lateral joint spaces was similar,and there was no significant difference in the size of tibial joint angle between groups(P>0.05),but there was significant difference between groups under the same stress at 90 degrees of knee flexion(P<0.001).The angulation of the control group was significantly larger than that of the experimental group,suggesting that the knee joint flexion gap was comparatively larger than that of the experimental group.The straightening gap is slightly relaxed and the width increases.There was no significant difference in KSS clinical and functional scores between the two groups before operation(P>0.05),but there was significant difference in KSS clinical and functional scores one month after operation(P<0.05).The value of the experimental group was slightly higher than that of the control group,suggesting that the improved gap balancing technique may be used in knee arthroplasty for 1 month after operation,and its clinical function is smaller than that of the measure resection technique.There was no significant difference in KSS clinical and functional scores between the two groups at 6 months follow-up(P>0.05).There was no significant difference in VAS score between the two groups before operation.The VAS score of the experimental group was slightly lower than that of the control group at 1 month follow-up(P<0.05).It suggests that the pain degree of the experimental group is mild and the recovery is better.There was no significant difference in the follow-up results between the two groups at 6 months after operation(p>0.05).ConclusionThe application of improved gap balancing in TKA has many advantages,which can achieve better balance between medial and lateral spaces,flexion and extension spaces,individualized femoral rotation angle adaptability and good post-operative function.The knee joint space distraction with pressure tester has some advantages such as low cost,easy operation and higher accuracy.It can be well used in knee arthroplasty with gap balancing technique or the mixed way.The self-made knee joint gap stretching pressure tester can simplify the operation process and shorten the operation time,which will hopefully further improve the clinical results of TKA.