Quantitative evaluation of residual bony impingement lesions after arthroscopic treatment for isolated pincer-type femoroacetabular impingement using three-dimensional CT / 中华骨科杂志

ABSTRACT

Objective To determine the clinical characteristics and its effect on the clinical efficacy of residual bony impingement lesion after hip arthroscopic osteoplasty for pincer-type femoroacetabular impingement.Methods There were 30 patients who underwent hip arthroscopic osteoplasty for isolated pincer-type femoroacetabular impingement from December 2010 to January 2012 and had a minimum follow-up period of 2 years,including 21 males and 9 females.The average age at surgery was 34.5 years (range from 28-42 years).All of the patients had no advanced hip arthritis and the T(o)nnis grade was 0-2.Radiological evaluation was performed by 3-dimensional CT.According to residual rate,these patients were divided into 3 groupsresidual rate ＜10％ group,residual rate of 10％-20％ groups and residual rate ＞20％ group.Results The average follow-up period was 26.3 months (range,22-34 months) and nineteen cases had residual bony impingement lesion after surgery.Among them,84.2％ of the residual bony impingement lesion was posterior to the acetabular actual resection zone.The preoperative and postoperative bony impingement angle were 77.47°±21.31° and 12.94°±18.04°,respectively.The residual rate was 16.7％± 8.83％.The modified Harris hip score got significantly improved from 55.18±7.96 preoperatively to 94.71±4.39 postoperatively.The overall satisfactory rate was 76.7％,and the postoperative modified Harris hip score for these three groups was 95.86±1.71,95.23±1.99 and 85.52±6.41,respectively.The postoperative modified Harris hip score in residual rate ＞20％ group was significantly worse than those in other two groups.The satisfactory rate was 92.9％,80.0％ and 33.3％,respectively.The satisfactory rate in residual rate ＞20％ group was significantly worse than those in other two groups.There was a significant negative linear relationship between the residual rate and postoperative modified Harris hip score (R2=0.516,P=0.001).Conclusion The incidence of residual bony impingement lesion after hip arthroscopic osteoplasty for pincer-type femoroacetabular impingement was 63.3％.The residual rate was 16.7％.The residual impingement lesion was mainly at the posterior part of the acetabulum.The patients with residual rate ＞20％ got significantly worse clinical score and satisfactory rate.