| Objective:To investigate the accuracy of " the first and second metatarsal interval" as the anatomical reference point for tibial coronal osteotomy in patients with severe osteoarthritis combined with different degrees of deformity,and to correlate the changes in Mechanical axis of the lower limb and the surgical efficacy after the operation.The purpose of this study was to observe and study the changes in lower limb alignment and the surgical efficacy of patients with different degrees of knee deformity after total knee arthroplasty,and to analyze them.Methods: A total of 83 patients（118 knees）who were operated with total knee arthroplasty in our department from August 2019 to January 2022.In the included cases,all the operations were performed by the same senior operator;The type of prosthesis used was the posterior stabilized prosthesis of the artificial knee.Patients with previous history of knee infection,history of periprosthetic fracture trauma,foot deformity,and non-first-time joint replacement cases were excluded."The first and second intermetatarsal interval" was used as the distal anatomical reference point for the coronal tibial osteotomy.The patients were divided into mild deformity group（<10°）,moderate deformity group（10°-20°）and severe deformity group（>20°）according to Krackow’s knee varus classification and Ranawat’s knee valgus classification.The Digimizer Image Analysis Software was used to measure preoperative and postoperative standard standing lateral radiographs of the treated knee,and full-length radiographs of both lower limbs.The indexes measured included: preoperative Medial Proximal Tibial Angle（MPTA）,mechanical Lateral Distal Femoral Angle（LDFA）and Hip-Knee-Ankle angle,and postoperative indexes included tibial plateau angle,femoral plateau angle,and mechanical axis angle.The preoperative and postoperative Angle changes of the above measurement indexes,as well as the changes of knee pain and functional scores in patients with mild,moderate and severe knee deformity in and between groups were analyzed and compared.SPSS25.0 was used to analyze whether there were differences in the changes of lower limb force lines before and after operation within and between groups.ResultsA total of 83 patients（118 knees）.There were 109 knees with varus and 9 knees with valgus.There were 51 people（70 knees）in mild deformity group,38 people（46 knees）in moderate deformity group and 1 person（2 knees）in severe deformity group.There were no significant differences in gender,age and body mass index among the three groups（P > 0.05）.In mild varus group,the medial Angle of proximal tibia was 86.79°±2.92° before operation and 89.74°±2.17° after operation,with statistical significance before and after operation（P < 0.05）.The mechanical Angle of lower limbs was 173.00°（175.00°,177.00°）before surgery and 176.00°（178.00°,179.00°）after surgery,with statistical significance before and after surgery（P < 0.05）.In moderate varus group,the medial tibial angle was 85.01°±4.76° before operation and 89.10°±1.98° after operation,which was statistically significant（P < 0.05）.The mechanical angle of lower limbs was 166.50°（164.00°,169.00°）before surgery and 177.00°（174.00°,177.00°）after surgery,which was statistically significant（P < 0.05）.Preoperative HSS score of mild malformation group was 50.9±8.90 and postoperative HSS score was 80.70±5.30,there was significant difference（P < 0.05）;Preoperative HSS score of patients in the moderate deformity group: preoperative HSS score was 48.40±7.50,postoperative HSS score was 80.7±4.9,there was significant difference（P < 0.05）.The improvement of preoperative and postoperative HSS score of patients in the two groups showed significant statistical difference.ConclusionThe use of " first and second metatarsal interval" as the distal reference point of coronal tibial osteotomy can correct the several deformity in total knee arthroplasty.This method is simple and high repeatable. |
PDF Full Text Request