Objective To investigate the efficiency of manual reduction combined with uni-lateral percutaneous kyphoplasty (PKP) in treating osteoporotic vertebral compression fracture (OVCF). Methods Between May 2005 and May 2009, the manual reduction combined with uni-lateral PKP was appl ied to treat 42 patients with OVCF (group A), and the simple uni-lateral PKP was appl ied to treat 43 patients with OVCF (group B) at the same period. The visual analogue scale (VAS), the vertebral height, and the Cobb angle were determined before operation, and at 3 days and 6 months after operation. Ingroup A, there were 6 males and 36 females aged 59-93 years (76.5 years on average) with an average disease duration of 7 days (range, 3 hours to 21 days); 27 segments of thoracic vertebrae and 31 segments of lumbar vertebrae were involved, including 15 segments at mild degree, 38 segments at moderate degree, and 5 segments at severe degree according to degree classification system of compression fractures of Zoarski and Peh. In group B, there were 9 males and 34 females aged 54-82 years (75.3 years on average) with an average disease duration of 7 days (range, 1 hour to 20 days); 26 segments of thoracic vertebrae and 35 segments of lumbar vertebrae were involved, including 21 segments at mild degree, 36 segments at moderate degree, and 4 segments at severe degree according to degree classification system of compression fractures of Zoarski and Peh. There were no significant difference (P gt; 0.05) in sex, age, affected site, degree, and disease duration between 2 groups. Results There was no significant difference (P gt; 0.05) in operative time, blood loss, or injected cement volume between 2 groups. No serious compl ication or death occurred in 2 groups. Cement leakage was observed in 4 cases (9.5%) of group A and in 5 cases (11.6%) of group B. The VAS scores after operation significantly decreased in 2 groups (P lt; 0.01). At 3 days and 6 months after operation, the VAS scores in group A were significantly lower than those in group B (P lt; 0.05). The postoperative compression rates of affected vertebral body in 2 groups significantly decreased (P lt; 0.01). The compression rates of affected vertebral body at 3 days and 6 months after operation, and the height recovery rate at 3 days after operation in group A were superior to those in groupB (P lt; 0.05). The postoperative Cobb angles in 2 groups were significantly diminished (P lt; 0.01). The Cobb angles at 3 days and 6 months after operation, and the recovery rate at 3 days after operation in group A were superior to those in group B (P lt; 0.05). Conclusion The cl inical efficiency of the manual reduction combined with uni-lateral PKP is superior to that of simple uni-lateral PKP in treatment of severe OVCF.
Objective To investigate the biomechanical influence ofvertebroplasty using autosolidification calcium phosphate cement (CPC) on thoracolumbar osteoporotic fractures. Methods Four cadaver specimens with osteoporosiswere applied to make spine unit. There were 2 females and 2 males, whose average age was 69 years.All underwent flexion-axial loading to result in vertebral body fracture. Following reduction, the middle fractured vertebral body were strengthened by the method of vertebroplasty, using CPC. Before fracture and after vertebroplasty, all were conducted biomechanical test. Results After being packed- CPC to the space in the fractured vertebral body, the strength andstiffness in vertebroplastic group (2 285±34 N，427±10 N/mm) were significantly higher than that in osteoporotic group (1 954±46 N，349±18 N/mm) (Plt;0.05). The vertebral height changing in vertebroplastic group(5.35±0.60 mm) were significantly lower than that in osteoporotic group (5.60±0.70 mm) (Plt;0.05). And the fractured body increases its strength and stiffnessby 16.92% and 22.31% respectively in comparison with its initial situation. Conclusion After being injected CPC into bone trabecular interspaces, the fractured vertebral bodies can restore its strength and stiffness markedly.
ObjectiveTo analyze the incidence of and prevention strategies for bone cement leakage after percutaneous vertebroplasty (PVP) or kyphoplasty (PKP) for treatment of osteoporotic vertebral compression fractures. MethodsA retrospective analysis was carried out on the clinical data of 178 patients who had 268 thoracolumbar osteoporotic compressions and underwent PVP or PKP from January 2010 to January 2013 in our hospital. We analyzed the causes of and prevention strategies for bone cement leakage. The therapeutic effect was observed after operation. We summarized the causes and prevention strategies for the bone cement leakage. ResultsStatistics showed that 51 vertebrae (19.0%) had bone cement leakage, including 31 vertebrae (29.2%) after PVP and 20 vertebrae (12.3%) after PKP. All patients had back pain relief after operation. One patient with bone cement leakage had the nerve root injured, which was relieved by decompression. Other patients had no reaction. ConclusionThe causes of cement leakage were related to the patients' own factors, but were more related to the operations. Adequate preparation before operation, correct surgical technology during operation, taking necessary precautions and X-ray monitoring are the key to the prevention of cement leakage.
ObjectiveTo compare the clinical efficacy and safety between percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral compression fracture (OVCF) with intravertebral vacuum cleft (IVC). MethodsBetween January 2010 and December 2013, 68 patients with single OVCF and IVC were treated, and the clinical data were retrospectively analyzed. Of 68 patients, 48 underwent PVP (PVP group) and 20 underwent PKP (PKP group). There was no significant difference in age, gender, disease duration, fracture level, bone mineral density (BMD), visual analogue scale (VAS), Oswestry disability index (ODI), and preoperative radiological parameters between 2 groups (P > 0.05). The intraoperative incidence of cement leakage, cement volume, and operative time were compared between 2 groups; VAS score was used for evaluation of back pain and ODI for evaluation of dysfunction; the incidence of adjacent vertebral fracture was observed within 2 years. The vertebral height and kyphotic angle were measured on X-ray films; the rate of vertebral compression (CR), reduction rate (RR), progressive height loss (PHL), reduction angle (RA), and progressive angle (PA) were calculated. ResultsThere was no significant difference in cement volume and the incidence of cement leakage between 2 groups (P > 0.05). The operative time in PVP group was shorter than that in PKP group, showing significant difference (t=-8.821, P=0.000). The mean follow-up time was 2.4 years (range, 2.0-3.1 years). The VAS scores and ODI were significantly reduced at 1 day, 1 year, and 2 years after operation when compared with preoperative scores (P < 0.05), but there was no significant difference between different time points after operation in 2 groups (P > 0.05). Adjacent vertebral fracture occurred in 5 cases (10.4%) of PVP group and in 2 cases (10.0%) of PKP group, showing no significant difference (χ2=0.003, P=0.963). BMD was significantly increased at 1 year and 2 years after operation when compared with preoperative BMD (P < 0.05), but no significant difference was found between 2 groups (t=0.463, P=0.642; t=0.465, P=0.646). The X-ray films showed that CR and kyphotic angle were significantly restored at immediate after operation in 2 groups (P < 0.05); but vertebral height and kyphotic angle gradually aggravated with time, showing significant difference between at immediate and at 1 and 2 years after operation (P < 0.05); there was no significant difference in CR and kyphotic angle between 2 groups at each time point (P > 0.05). RR, RA, PHL, and PA showed no significant difference between 2 groups (P > 0.05). ConclusionThere is similar clinical and radiological efficacy between PVP and PKP for treatment of OVCF with IVC. Re-collapse could happen after operation, so strict observation and follow-up are needed.
ObjectiveTo investigate the feasibility and mechanical properties of polymethyl methacrylate (PMMA) bone cement and allogeneic bone mixture to strengthen sheep vertebrae with osteoporotic compression fracture.MethodsA total of 75 lumbar vertebrae (L1-L5) of adult goats was harvested to prepare the osteoporotic vertebral body model by decalcification. The volume of vertebral body and the weight and bone density before and after decalcification were measured. And the failure strength, failure displacement, and stiffness were tested by using a mechanical tester. Then the vertebral compression fracture models were prepared and divided into 3 groups (n=25). The vertebral bodies were injected with allogeneic bone in group A, PMMA bone cement in group B, and mixture of allogeneic bone and PMMA bone cement in a ratio of 1∶1 in group C. After CT observation of the implant distribution in the vertebral body, the failure strength, failure displacement, and stiffness of the vertebral body were measured again.ResultsThere was no significant difference in weight, bone density, and volume of vertebral bodies before decalcification between groups (P>0.05). After decalcification, there was no significant difference in bone density, decreasing rate, and weight between groups (P>0.05). There were significant differences in vertebral body weight and bone mineral density between pre- and post-decalcification in 3 groups (P<0.05). CT showed that the implants in each group were evenly distributed in the vertebral body with no leakage. Before fracture, the differences in vertebral body failure strength, failure displacement, and stiffness between groups were not significant (P>0.05). After augmentation, the failure displacement of group A was significantly greater than that of groups B and C, and the failure strength and stiffness were less than those of groups B and C, the failure displacement of group C was greater than that of group B, and the failure strength and stiffness were less than those of group B, the differences between groups were significant (P<0.05). Except for the failure strength of group A (P>0.05), the differences in the failure strength, failure displacement, and stiffness before fracture and after augmentation in the other groups were significant (P<0.05).ConclusionThe mixture of allogeneic bone and PMMA bone cement in a ratio of 1∶1 can improve the strength of the vertebral body of sheep osteoporotic compression fractures and restore the initial stiffness of the vertebral body. It has good mechanical properties and can be used as one of the filling materials in percutaneous vertebroplasty.