OBJECTIVE: To analyze the safety and effectiveness of 3D printing prefabricated nail path model assisted lumbosacral hemivertebra orthopaedic surgery. METHODS: A retrospective analysis was performed on 8 patients with lumbosacral hemivertebra deformity admitted from January 2016 to July 2021, including 3 males and 5 females, aged 6 to 15 at the time of surgery. The hemivertebra of 4 cases located on the left side and 4 cases on the right side. The hemivertebra of 1 case located at L_2,3, 2 cases at L_3,4, 2 cases at L_4,5, and 3 cases at L₅S₁. Four cases were fully segmented hemivertebra and 4 cases were incomplete segmented hemivertebra. The patient CT data was imported into Mimics 21.0 software for modeling, and then the model data was imported into 3-Matic software. The vertebra requiring screw placement was selected to simulate the optimal screw placement angle and length, and the model was printed for preoperative planning and intraoperative guidance. All patients underwent orthopedic surgery with the aid of 3D printing preset nail path model. The safety and effectiveness of the 3D printing prefabricated nail tunnel model assisted lumbosacral hemivertebra orthopaedic surgery was evaluated by comparing the imaging parameters of the patients. The main outcome measures were the Cobb angle of the main curve, the Cobb angle of the proximal compensatory curve, the coronal balance index C₇ plumb line-center sacral vertical line(C₇PL-CSVL), the accuracy of nail placement, and the correction rate of scoliosis before surgery, 1 week and 1 year after surgery. RESULTS: All of 8 patients were followed up for 13 to 31 months. A total of 98 pedicle screws were placed in 8 patients. The number of pedicle screw grades A, B, C, D, E was 38, 46, 10, 4, 0 screws. The screws of grade A and B were defined as good position, the accuracy rate of screw placement was 85.7%. The Cobb angle of the main curve were 21° to 38° before operation, 5° to 11° at 1 week after operation, 7°to 12° at 1 year after operation. The Cobb angle of the proximal compensatory curve were 16° to 39° befoer operation, 7° to 12 °at 1 week after operation, 7° to 14° at 1 year after operation, the correction effect remained good with no correction loss. The coronal balance index C7PL-CSVL were 20 to 35 mm before operation, 11 to 18 mm at 1 week after operation, 10 to 16 mm at 1 year after operation, the coronal imbalance improved. The scoliosis correction rate was 65.6% to 84.2% 1 week after surgery, and 61.9% to 81.6% 1 year after surgery. CONCLUSION The use of 3D printing prefixed nail tunnel model in lumbosacral hemivertebra osteotomy is safe and effective, and can significantly improve patients' local deformities. It is a reliable method to assist lumbar sacral hemivertebra osteotomy.
Humans ; Printing, Three-Dimensional ; Female ; Male ; Adolescent ; Retrospective Studies ; Child ; Lumbar Vertebrae/surgery* ; Sacrum/abnormalities* ; Bone Nails ; Orthopedic Procedures/instrumentation*

Lumbar spinal stenosis (LSS) is mostly caused by osteoarthritis (spondylosis). Clinically, the symptoms of patients with LSS can be categorized into two groups; regional (low back pain, stiffness, and so on) or radicular (spinal stenosis mainly presenting as neurogenic claudication). Both of these symptoms usually improve with appropriate conservative treatment, but in refractory cases, surgical intervention is occasionally indicated. In the patients who primarily complain of radiculopathy with an underlying biomechanically stable spine, a decompression surgery alone using a less invasive technique may be sufficient. Preoperatively, with the presence of indicators such as failed back surgery syndrome (revision surgery), degenerative instability, considerable essential deformity, symptomatic spondylolysis, refractory degenerative disc disease, and adjacent segment disease, lumbar fusion is probably recommended. Intraoperatively, in cases with extensive decompression associated with a wide disc space or insufficient bone stock, fusion is preferred. Instrumentation improves the fusion rate, but it is not necessarily associated with improved recovery rate and better functional outcome.
Back Pain ; Congenital Abnormalities ; Constriction, Pathologic ; Decompression ; Failed Back Surgery Syndrome ; Humans ; Lumbar Vertebrae ; Osteoarthritis ; Radiculopathy ; Spinal Fusion ; Spinal Stenosis* ; Spine ; Spondylolysis

Lumbar spinal stenosis (LSS) is mostly caused by osteoarthritis (spondylosis). Clinically, the symptoms of patients with LSS can be categorized into two groups; regional (low back pain, stiffness, and so on) or radicular (spinal stenosis mainly presenting as neurogenic claudication). Both of these symptoms usually improve with appropriate conservative treatment, but in refractory cases, surgical intervention is occasionally indicated. In the patients who primarily complain of radiculopathy with an underlying biomechanically stable spine, a decompression surgery alone using a less invasive technique may be sufficient. Preoperatively, with the presence of indicators such as failed back surgery syndrome (revision surgery), degenerative instability, considerable essential deformity, symptomatic spondylolysis, refractory degenerative disc disease, and adjacent segment disease, lumbar fusion is probably recommended. Intraoperatively, in cases with extensive decompression associated with a wide disc space or insufficient bone stock, fusion is preferred. Instrumentation improves the fusion rate, but it is not necessarily associated with improved recovery rate and better functional outcome.
Back Pain ; Congenital Abnormalities ; Constriction, Pathologic ; Decompression ; Failed Back Surgery Syndrome ; Humans ; Lumbar Vertebrae ; Osteoarthritis ; Radiculopathy ; Spinal Fusion ; Spinal Stenosis* ; Spine ; Spondylolysis

Placing instrumentation into the ilium has been shown to increase the biomechanical stability and the fusion rates, but it has some disadvantages. The diagonal S2 screw technique is an attractive surgical procedure for degenerative lumbar deformity. Between 2008 and 2010, we carried out long fusion across the lumbosacral junction in 13 patients with a degenerative lumbar deformity using the diagonal S2 screws. In 12 of these 13 patients, the lumbosacral fusion was graded as solid fusion with obvious bridging bone (92%). One patient had a rod dislodge at one S2 screw and breakage of one S1 screw and underwent revision nine months postoperatively. So, we present alternative method of lumbopelvic fixation for long fusion in degenerative lumbar deformity using diagonal S2 screw instead of iliac screw.
Aged ; *Bone Screws ; Cohort Studies ; Female ; Humans ; Ilium/surgery ; Lumbar Vertebrae/*abnormalities/*surgery ; Male ; Middle Aged ; Sacrum/surgery ; Spinal Fusion/adverse effects/*instrumentation/methods ; Treatment Outcome

OBJECTIVETo evaluate the early outcomes of children with congenital scoliosis treated by one-stage transpedicular hemi-vertebra resection.

METHODSFrom July 2005 to June 2006, 27 consecutive cases of congenital scoliosis managed by one-stage transpedicular hemi-vertebra resection with instrumentation were investigated retrospectively. There were 11 girls and 16 boys, with a mean age of 5.5 years at surgery (range 1.3 - 10.0 years). Location of the hemi-vertebra was in the thoracic spine in 12 cases and in the lumbar spine in 15 cases. Radiographic evaluations were performed on the preoperative, postoperative, and latest follow-up standing posteroanterior and lateral radiographs.

RESULTSThe average operation time was 4 hours (range 3-6 hours), and the mean blood loss during operation was 750 ml (range 300 - 2200 ml). The mean fusion level was 2 to 7 segments, average 4.4 segments. The average follow-up period was 16 months (range 12 - 34 months). Mean Cobb angle of the total main curve was 40.0° before surgery, 12.6° after surgery, and 15.2° at latest follow-up. Mean Cobb angle of the segmental main curve was 35.6° before surgery, 11.6° after surgery, and 12.1° at latest follow-up. The trunk shift was improved from 16.5 mm before operation to that of 7.5 mm after the operation and 7.6 mm at the latest follow-up. Compensatory cranial curve improved from 19.4° before surgery to 8.9° after surgery, and compensatory caudal curve improved from 26.3° to 12.8°. The angle of segmental kyphosis was 26.4° before surgery and 14.6° after surgery in cases with thoracic hemivertebrae, and averaged 11.2° before surgery and 3.9° after surgery in cases with lumbar hemivertebrae. Peri-operative complications included two pedicle screws malpositioning and one case with pelvic tilt. There was no neurological complication.

CONCLUSIONOne-stage transpedicular hemi-vertebra resection with instrumentation has a good capability of correcting deformity on the frontal and sagittal planes, which is available in children with middle or lower thoracic or lumbar hemivertebrae.

Child ; Child, Preschool ; Female ; Follow-Up Studies ; Humans ; Infant ; Lumbar Vertebrae ; abnormalities ; surgery ; Male ; Retrospective Studies ; Scoliosis ; congenital ; surgery ; Thoracic Vertebrae ; abnormalities ; surgery ; Treatment Outcome