Percutaneous Kyphoplasty For Treatment Of Osteoporotic Vertebral Fractures With Cracked Posterior Vertebral Body Wall

Objective To explore the efficacy and feasibility of percutaneous kyphoplasty(PKP)in the treatment of osteoporotic vertebral fractures with cracked posterior vertebral body wall, and the prevention of cement leakage.Methods From July 2008 until January 2014, 31 patients with osteoporotic vertebral fractures with cracked posterior vertebral body wall underwent kyphoplasty. The patients were analyzed retrospectively. 31 patients were treated by percutaneous kyphoplasty. The cracked posterior vertebral body wall was confirmed by CT. There are 12 males and 19 females, with an average age of 73.7 years range from 61.5 to 90 years old including 31 level from T11 to T4( 1 case of T11, 8 cases of T12, 15 cases of L1, 6 cases of L2, 15 cases of L4). The mean follow-up period was 17months(12-26 months). X-ray,CT,MRI and clinical features were conducted to identify responsible vertebral bodies before the operations.The visual analogue scale(VAS) scores, Oswestry disability index(ODI) and radiographic results were recorded before the operation, 2 days after the operation and the final follow-up respectively. The inflatable bone tamp was the fractured vertebral body transpedicularly under fluoroscopic guidance.The balloon was inflated slowly with low pressure. High viscosity bone cement was inserted into the cavity made by the balloon under “C”-arm monitoring. The pain and disability level of each patient were measured by using the visual analogue scale(VAS) scores and oswestry disability index(ODI) were recorded beforethe operation, 2 days after the operation and the final follow-up respectively. Wedge angle(the angle between superior endplate and inferior endplate at the fractured vertebra),kyphotic angle(the angle measured above and below fractured vertebra),anterior vertebral height,middle vertebral height were recorded were recorded before the operation, 2 days after the operation and the final follow-up respectively. Cement leakage and other complications were recorded. Comparisons of the data between preoperatively, 2 days postoperatively and at the final follow-up were analyzed by paired sample t-test.Results The mean VAS pain score decreased significantly from 7.55±1.15 preoperatively to 1.77 ± 0.94 postoperatively(P < 0.05), at the last follow-up 2.13 ± 0.78 at the last follow-up;The ODI score varied from 74.52±10.12% preoperatively to 26.26±10.34% postoperatively(P<0.05),and was maintained at 29.73±9.77%at the last follow-up; The anterior vertebral height had improved from 20.20 ± 5.62 mm preoperatively to24.46±6.44 mm postoperatively(P<0.05),at the last follow-up 24.17± 6.39mm; The middle vertebral height had improved from 22.66 ± 5.72 mm preoperatively to 26.45±6.61 mm postoperatively(P<0.05),and was maintained at 25.67±6.19 mm at the last follow-up;The kyphotic angle(the angle measured above and below fractured vertebra) was corrected from 19.15±9.98°preoperatively to 15.04±9.53°postoperatively(P<0.05), 15.18±9.51°at the last follow-up;The wedge angle of the fractured vertebras(the angle between superior endplate and inferior endplate at the fractured vertebra) were corrected from 16.77±6.02°preoperatively to 12.34±5.53°postoperatively(P<0.05),12.47±5.49°at the last follow-up。 All indexes were significantly improved after operation, and there were no significant differences between the indexes at 2 days after the operation and the indexes the final follow-up than before(P>0.05).Conclusion Percutaneous kyphoplasty is an optional method to treat osteoporotic vertebralfractures with cracked posterior vertebral body wall.