The Clinical Study Of Minimal Invasive Total Hip Arthroplasty Reserving Articular Capsule

Objective: To investigate the opration method and clinical significance ofminimal invasive Total Hip Arthroplasty (THA) reserving articular capsule. Andprovide clinical supportion to the treatment of hip joint disorder minimal with TotalHip Arthroplasty (THA).Methods:102cases of THA were divided into two groups:56cases of minimalinvasive total hip arthroplasty (MiTHA) reserving articular capsule and46cases ofordinary incision without reserving articular capsule (OiTHA). All patients weretreated fitstly in Yongzhou hospital from2008.1to2010.10. Apart from the length ofincision and whether reserving articular capsule or not，the patient’s condition,prosthesis selection, and postoperative treatment of the two groups were almost thesame. All patients were performed a6-33month’s follow-up (23±4.2months).Contrast observations were made between the two groups of operation time, lengthof incision, blood loss during operation, hospital stay, dislocation of hip joint, X rayresults and Harris scoresResults:1) The operation time is from48minutes to95minutes（67.67±7.2）inMiTHA，while in OiTHA it is from43minutes to80minute（s60.49±10.9）, and thereis no clear difference between MiTHA and OiTHA (P>0.05). The average length ofincision is9.1±0.6centimeter in MiTHA and13.4±1.4centimeter in OiTHA; in termsof length of the incision and the appearance in the surgical site, MiTHA has obviousadvantages over OiTHA (P <0.05). The volume of blood loss during operation,intraoperative blood transfusions, postoperative drainage，and level of haemoglobinbefore and after operation in MiTHA and OiTHA are80-180（115.36±13.2）ml/100-240（156.25±16.6）ml,0-4（1.70±0.3）u/0-6（2.96±0.4）u,110-320（170.67±16.6）ml/150-350（195±18.2）ml,90-130（110.50±10.7）g/L/90-125（108.84±11.5）g/Land70-120（96.43±7.1）g/L/60-110（82.58±6.8）g/L, respectively. Besides volumeof postoperative drainage and level of hemoglobin before operation, there are significant differences among other items (P <0.05). The average hospital stay is9-16（11.84±2.9）days in MiTHA while it is10-18（12.29±3.2）days in OiTHA (P>0.05).2）In the early stage after operation, dislocation ratio of hip joint is1.78%(1/56) inMiTHA and6.52%（3/46）in OiTHA; there is obivious differences between the twogroups (P<0.05); and no patient with dislocation of hip joint is found during thefollow-up one month after operation.3）X ray results in MiTHA and OiTHA are all satisfactied, and incidence of femoralvarus or valgus in OiTHA was higher than that in MiTHA (P <0.05). There is nosignificant difference of the centre of femoral handle, the cup anteversion andabduction angle, cup Center satisfaction rate, adhesion rate of acetabulum-prosthesis,fixed ratio of femur-prosthesis between MiTHA and OiTHA (P>0.05).4）The Harris scores before operation are respectively32-53（43.42±5.5）and30-58（44.67±6.2）in MiTHA and OiTHA，without any significant difference (P>0.05);the Harris scores are discharged to46-70（54.53±6.7）and42-64(48.36±5.9) inMiTHA and OiTHA respectively after operation and there is significant differencebetween them (P <0.05). After operation6months the Harris scores are88-96(92.78±8.5) and87-97(92.44±9.1) in MiTHA and OiTHA respectively，without any significant difference (P>0.05).Conclusion：1) There are more merits such as smaller trauma, better appearance ofthe surgical site, lower blood loss, satisfaction of X ray results for prosthesis positionand Harris scores in MiTHA. And performing MiTHA in treatment of suitablepatients can get better clinic outcome.2）Reserving and repairing the joint capsule can contribute to the early recovery ofsoft tissue structure in back of hip joint and rebuild balance of biomechanics of hipjoint. And it is of some clinic significance to prevention of dislocation of hip joint inthe early stage after THA.