Effects of extracorporeal shock wave to the removal of cemented femoral prostheses in the revision of artificial hip replacement

SUN Ying-hua; JIAO Zhao-de; WANG Li; ZHENG Xian-you; WANG Fu-chao

doi:10.3969/j.issn.2095-252X.2013.08.007

Abstract： Objective To investigate the effects of extracorporeal shock wave ( ESW ) to the removal of cemented femoral prostheses in the revision of artificial hip replacement ( AHR ). Methods The inclusion criteria were stated as following: patients ( 45-79 years old ) underwent revision 5 to 20 years after the initial operation;aseptic loosening of cemented femoral prostheses;unilateral revision and domestic prostheses and bone cements in the initial operation;volunteered to participate in this study and sign informed consents. According to the single or dual number of admission sequence, a total of 32 patients meeting the inclusion criteria were randomly divided into 2 groups:the intervention group ( n=16 ), who were treated with preoperative ESW therapy once a day for 5 days and 30 minutes each time, amounting to 5 times with 10 000 pulses in all, and the control group ( n=16 ), who were not treated with preoperative ESW therapy. The same person was in charge of recording the statistical data of the 2 groups according to the 4 standards, including complete removal ( disposable removal ), cutting femurs and removing the implants ( impossible to eradicate or only partially removed ), time-consuming calculation ( from the beginning of the removal until all the femoral implants were removed ) and bleeding volume calculation ( from skin incision to skin suture ). Furthermore, the Harris score was used to evaluate the 4 aspects 1 week before the surgery and 1 month after the surgery, including pain, function, range of motion and joint deformity. Results The cases that the implants were completely removed in the intervention group ( 8 out of 16 cases, 50.00%) were more than that in the control group ( 2 out of 16 cases, 12.50%) ( P<0.05 ). On the other hand, compared with that in the control group ( 10 out of 14 cases, 71.43%), the cases that the femurs were cut and the implants were not completely removed were less in the intervention group ( 2 out of 8 cases, 25.00%) ( P<0.05 ). Meanwhile, less time was needed in the intervention group ( 310.1±129.5 s ) than that in the control group ( 978.9±110.2 s ) for the removal of the implants ( P<0.01 ), and there was less amount of bleeding in the intervention group ( 610.9±126.5 ml ) than that in the control group ( 1110.1±140.4 ml ) ( P<0.01 ). There were no significant differences ( P>0.05 ) in the Harris score 1 week before the surgery between the intervention group ( 69.1±4.5 points ) and the control group ( 70.2±5.2 points ), but the Harris score 1 month after the surgery was higher in the intervention group ( 94.1±3.5 points ) than that in the control group ( 90.9±4.2 points ) ( P<0.05 ). Conclusions In the revision surgery of AHR, ESW is helpful in removing the cemented femoral prostheses.