Objective To investigate the effect of preventing the loss of correction and vertebral defects after thoracolumbar burst fractures treated with recombinant human bone morphogenetic protein 2 (rhBMP-2) and allogeneic bone grafting in injured vertebra uniting short-segment pedicle instrumentation. Methods A prospective randomized controlled study was performed in 48 patients with thoracolumbar fracture who were assigned into 2 groups between June 2013 and June 2015. Control group (n=24) received treatment with short-segment pedicle screw instrumentation with allogeneic bone implanting in injured vertebra; intervention group (n=24) received treatment with short-segment pedicle screw instrumentation combining with rhBMP-2 and allogeneic bone grafting in injured vertebra. There was no significant difference in gender, age, injury cause, affected segment, vertebral compression degree, the thoracolumbar injury severity score (TLICS), Frankel grading for neurological symptoms, Cobb angle, compression rate of anterior verterbral height between 2 groups before operation (P>0.05). The Cobb angle, compression rate of anterior vertebral height, intervertebral height changes, and defects in injured vertebra at last follow-up were compared between 2 groups. Results All the patients were followed up 21-45 months (mean, 31.3 months). Bone healing was achieved in 2 groups, and there was no significant difference in healing time of fracture between intervention group [(7.6±0.8) months] and control group [(7.5±0.8) months] (t=0.336, P=0.740). The Frankel grading of all patients were reached grade E at last follow-up. The Cobb angle and compression rate of anterior verterbral height at 1 week after operation and last follow-up were significantly improved when compared with preoperative ones in 2 groups (P<0.05). There was no significant difference in Cobb angle and compression rate of anterior verterbral height between 2 groups at 1 week after operation (P>0.05), but the above indexes in intervention group were better than those in control group at last follow-up (P<0.05). At last follow-up, there was no significant difference of intervertebral height changes of internal fixation adjacent upper position, injured vertebra adjacent upper position, injured vertebra adjacent lower position, and internal fixation adjacent lower position between 2 groups (P>0.05). Defects in injured vertebra happened in 18 cases (75.0%) in control group and 5 cases (20.8%) in intervention group, showing significant difference (χ2=14.108, P=0.000); and in patients with defects in injured vertebra, bone defect degree was 7.50%±3.61% in control group, and was 2.70%±0.66% in intervention group, showing significant difference (t=6.026, P=0.000). Conclusion Treating thoracolumbar fractures with short-segment pedicle screw instrumentation with rhBMP-2 and allogeneic bone grafting in injured vertebra can prevent the loss of correction and vertebral defects.
ObjectiveTo investigate the short- and mid-term effectiveness of revision hip arthroplasty by using impaction bone allograft and acetabular components in treatment of severe acetabular defects.MethodsA clinical data of 42 patients (44 hips) with severe acetabular defects between February 2011 and May 2018 were retrospectively analyzed. All patients underwent revision hip arthroplasty by using impaction bone allograft and acetabular components. Cemented cup (24 cases, 24 hips) and non-cemented cup (18 cases, 20 hips) were used in the revision surgery. There were 17 males and 25 females with an average age of 62.8 years (range, 22-84 years). The interval between the first total hip arthroplasty and revision was 2.5-12.0 years (mean, 8.3 years). The patients were accepted revision surgery for prosthesis aseptic loosening in 32 hips (31 cases) and the periprosthetic infection in 12 hips (11 cases). Twenty-nine hips (28 cases) were Paprosky type ⅢA and 15 hips (14 cases) were type ⅢB. The preoperative Harris score was 22.25±10.31 and the height of hip rotation center was (3.67±0.63) cm and the length difference of lower limbs was (3.41±0.64) cm.ResultsThe operation time was 130-245 minutes (mean, 186 minutes) and the intraoperative blood loss was 600-2 400 mL (mean, 840 mL). The postoperative drainage volume was 250-1 450 mL (mean, 556 mL). Superficial infection of the incision occurred in 1 case, and the incisions healed by first intention in the other patients. All patients were followed up 6-87 months, with an average of 48.6 months. At last follow-up, the Harris score was 85.85±9.31, which was significantly different from the preoperative score (t=18.563, P=0.000). Imaging examination revealed that the allogeneic bone gradually fused with the host bone, and no obvious bone resorption was observed. At last follow-up, the height of the hip rotation center was (1.01±0.21) cm, which was significantly different from the preoperative level (t=17.549, P=0.000); the length difference of lower limbs was (0.62±0.51) cm, which was significantly different from the preoperative level (t=14.211, P=0.000). The Harris score in the cemented group and non-cemented group increased significantly at last follow-up. The height of the hip rotation center decreased, and the hip rotation centers of both groups were within the Ranawat triangle zone. The length difference of the lower limbs also decreased, and the differences in all indexes were significant between pre- and post-operation (P<0.05). There was significant difference in the height of the hip rotation center between groups (t=2.095, P=0.042), but there was no significant difference in the Harris score and the length difference of lower limbs between groups (P>0.05).ConclusionFor severe acetabular defect (Paprosky type Ⅲ), the hip can be reconstructed with the impaction bone allograft and cemented or non-cemented components in revision hip arthroplsty. The short- and mid-term effectiveness are satisfactory.
ObjectiveTo summarize the management principle and clinical suggestions of the osteotomy gap of opening wedge high tibial osteotomy (OWHTO).MethodsThe related literature of the osteotomy gap of OWHTO in recent years was reviewed, summarized, and analyzed.ResultsDelayed union and non-union of the osteotomy gap are main complications of OWHTO. Tomofix plate, as locking steel plate, has the characteristics of angular stability and can better maintain the stability of the osteotomy gap, promote bone healing, and avoid loss of correction. There are some treatment options for the osteotomy gap site, such as, without bone, autologous bone graft, allogeneic bone graft, bone substitute materials graft, and augment factor graft to enhance bone healing. When the osteotomy gap is less than 10 mm, it achieves a good outcome without bone graft. For the obesity, lateral hinge fracture, large osteotomy gap, or correction angle more than 10°, the bone graft should be considered. In cases whose osteotomy gap is nonunion or delayed union, the autologous bone graft is still the gold standard. When the osteotomy gap repaired with the allogeneic bone graft, it is better to choose fragmented cancellous or wedge-shaped cancellous bone, combining with the locking plate technology, also can achieve better bone union. The bone substitute material of calcium-phosphorus is used in the osteotomy gap, which has the characteristics of excellent bone conduction, good biocompatibility, and resorption, combining with the locking plate technology, which can also achieve better bone union in the osteotomy gap. The augment factors enhance the bone healing of the osteotomy gap of OWHTO is still questionable. The bone union of the osteotomy gap is also related to the size of the osteotomy gap and whether the lateral hinge is broken or not.ConclusionNo matter what type of materials for the osteotomy gap, OWHTO can improve the function and relieve pain for knee osteoarthritis. More randomized controlled trials are needed to provide evidence for clinical decision to determine which treatment option is better for the osteotomy gap of OWHTO.
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.