Transdural circumferential decompression for thoracic spinal stenosis caused by beak-type ossification of the posterior longitudinal ligament: a technical note.

PURPOSE: Thoracic myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine is usually progressive and responds poorly to conservative therapy, making surgery the only effective treatment option. A variety of surgical procedures have been developed to treat thoracic OPLL. However, the optimal surgical approach for removal of thoracic OPLL remains unclear. In the present study, we described a newly modified posterior approach for the removal of OPLL: circular decompression via dural approach, and complete removal of OPLL can be achieved under direct vision and without neurological deficit. MATERIALS AND METHODS: Three patients with beak-type thoracic OPLL presented with progressive thoracic myelopathy and leg weakness. Magnetic resonance imaging showed the spinal cord severely compressed. The surgical management of the three patients involved the 'cave-in' circular decompression and transdural resection of OPLL. RESULTS: Transdural circumferential decompression was successfully performed in all three patients. Clinical outcome measures, including pre- and postoperative radiographic parameters, were assessed. All of the patients were followed up for an average of 12 months (ranging from 10 to 15 months), and no surgery-related complications occurred. Weakness relief and neural function recovery were satisfactorily achieved in all patients by the final follow-up. CONCLUSIONS: Transdural circumferential decompression was an effective method for thoracic spinal stenosis caused by concurrent beak-type OPLL, by which OPLL could be safely removed. It is especially useful when there is a severe adhesion between the dura OPLL.

Application of open-door laminoplasty with ARCH plate fixation in cervical intraspinal tumors.

BACKGROUND: The open-door laminoplasty is an effective procedure for the treatment of cervical spondylotic myelopathy. However, little information is available about the surgical results of open-door laminoplasty in the treatment of intraspinal tumors. In the present study, we aimed to investigate the clinical effect of open-door laminoplasty with ARCH plate fixation in the treatment of cervical intraspinal tumors. METHODS: This was a retrospective study. From January 2013 to May 2018, 38 patients (13 males and 25 females, the average age of 44 ± 17 years) with cervical intraspinal tumors underwent open-door laminoplasty with ARCH plate fixation in our hospital. The operation time, blood loss, pre- and postoperative visual analog scale (VAS), and Japanese Orthopedic Association (JOA) scores were determined. To determine the radiographic outcomes, cervical X-ray film and magnetic resonance imaging (MRI) were performed before and after the operation, and cervical X-ray sagittal film was used to measure Cobb angle. The clinical data before and after the operation were compared by t-test. RESULTS: A total of 38 patients underwent a successful operation and demonstrated primary healing. The average operation time was 113 ± 12 min. The average blood loss was 120 ± 19 mL. All patients were followed up for 26.1 ± 2.8 months, and the final follow-up time was more than 24 months. VAS scores were much better at 24 months after operation compared with those before the operation, which were decreased from 6.1 ± 1.1 to 1.4 ± 0.7 (t = 32.63, P < 0.01). The JOA score was improved from 9.9 ± 1.5 to 15.5 ± 0.6 (t = - 18.36, P < 0.01), and the mean JOA recovery rate was 79% ± 11% at 24 months after the operation. There was no significant difference in Cobb angle between pre-operation and 24 months after the operation, which was 9.8 ± 2.6 and 10.3 ± 3.1 respectively (t = - 0.61, P > 0.05). Neither spinal malalignment on the coronal plane nor displacement of the laminoplasty flap was observed on postoperative cervical X-ray and MRI examinations at the final follow-up. CONCLUSIONS: Open-door laminoplasty with ARCH plate fixation was a safe and effective surgical approach for the treatment of cervical intraspinal tumors.

Culture-negative versus culture-positive in pyogenic spondylitis and analysis of risk factors for relapse.

OBJECTIVES: This study aims to compare and analyze the clinical features, diagnosis, treatment and prognosis of culture-negative and culture-positive primary pyogenic spondylitis. METHODS: In a retrospective analysis, 202 cases of adult primary pyogenic spondylitis with complete clinical data in our hospital from January 2013 to January 2020 were divided into two groups according to bacterial culture results: culture negative (n = 126) and culture positive (n = 76). We compare the clinical characteristics, diagnosis, treatment and prognosis of patients with different culture results. RESULTS: The culture positive rate was 37.62% (76/202). There were no significant differences in age, gender, affected segment, spinal abscess, diabetes mellitus, course of disease, surgery, recurrence, and follow-up time between the two groups (p>.05). There were statistically significant differences in hospital admission erythrocyte sedimentation rate (ESR), admission C-reactive protein (CRP), admission white blood cell (WBC) count, discharge ESR, discharge CRP, ESR decline rate, CRP (p<.05). There were statistically significant differences in the rate of decline, hospitalization days, and body temperature ≥38 °C (p<.05). Higher CRP levels on admission, antibiotic treatment time <6 weeks, and body temperature ≥ 38 °C are independent risk factors for infection recurrence. CONCLUSIONS: The culture-negative group's admission WBC, admission ESR, admission CRP, discharge ESR, discharge CRP, ESR decline rate, CRP decline rate, and hospital stay were lower than the culture positive group, the difference was statistically significant (p<.05). The independent risk factors for infection recurrence are higher CRP levels in hospital admission, antibiotic treatment time <6 weeks, and body temperature ≥ 38 °C.

3D printed polycaprolactone/ß-tricalcium phosphate/carbon nanotube composite - Physical properties and biocompatibility.

Three-dimensional (3D) printing is a bio-fabrication technique used to process tissue-engineered scaffolds for bone repair and remodeling. Polycaprolactone (PCL)/ß-tricalcium phosphate (TCP) has been used as a base and osteoconductive biomaterial for bone tissue engineering in the past decades. The current study reveals the fabrication of a polycaprolactone (PCL)/ß-tricalcium phosphate (TCP) scaffold by incorporating carbon nanotubes (CNT) via 3D printing. The physical properties and cytocompatibility of a new type of tissue engineering composite from polycaprolactone/ß-tri-calcium phosphate/carbon nanotubes were investigated, and it was an absorbable scaffold prepared via furnace deposition 3D printing technology. The scaffold was designed with CAD software, and the composite material was fabricated via 3D printing. The printed composite material was tested for mechanical strength, scanning electron microscope (SEM) analysis, porosity calculation, systemic toxicity test, hemolysis rate determination, and effect on the proliferation of rat adipose-derived stem cells cultured in vitro. A composite scaffold with a length of 15 mm, width of 10 mm, and height of 5 mm was manufactured through CAD software drawing and 3D printing technology. Scanning electron microscopy measurements and analysis of the internal pore size of the stent are appropriate; the pores are interconnected, and the mechanical strength matches the strength of human cancellous bone. The calculated porosity of the stent was >60%, non-toxic, and non-hemolytic. The proliferation activity of the ADSC co-cultured with different scaffold materials was as follows: polycaprolactone/ß-tricalcium phosphate/0.2% carbon nanotube scaffolds > polycaprolactone/ß-tricalcium phosphate/0.1% carbon nanotube scaffolds > polycaprolactone/ß-tricalcium phosphate/0.3% carbon nanotube scaffolds > polycaprolactone/ß-tricalcium phosphate scaffolds (P < 0.05). The results showed that polycaprolactone/ß-tricalcium phosphate/0.2% carbon nanotube scaffolds promoted the adhesion and proliferation of ADSC. The combination of 3D printing technology and CAD software can be used to print personalized composite stents, which have the characteristics of repeatability, high precision, and low cost. Through 3D printing technology, combining a variety of materials with each other can provide the greatest advantages of materials. The waste of resources was avoided. The prepared polycaprolactone/ß-tri-calcium phosphate/0.2% carbon nanotube scaffold has a good pore structure and mechanical properties that mimic human cancellous bone, is non-toxic and non-hemolytic, and is effective in promoting ADSC proliferation in vitro. Given this correspondence, 3D printed scaffold shows good biocompatibility and strength, and the fabrication method provides a proof of concept for developing scaffolds for bone tissue engineering applications.

A Review and Summary of Patients with Symptomatic Postoperative Discal Pseudocysts of the Lumbar Spine.

OBJECTIVE: Postoperative discal pseudocyst (PDP) is a rare complication after discectomy. This study aimed to summarize the characteristics, pathological mechanisms and management of PDPs. METHODS: Nine patients with PDP who received surgical treatment at our institution from January 2014 to December 2021 were retrospectively reviewed. A systematic review of the literature on PDP was performed. The demographic data, clinical and imaging features, surgical options and patient prognosis were analyzed. RESULTS: Among the nine patients treated at our center, seven were male and two were female. The mean patient age (± standard deviation) at the time of surgery was 28.3 ± 5.7 years (range 18-37 years). The first operation performed on seven patients was percutaneous endoscopic transforaminal discectomy (PETD) and two patients underwent microdiscectomy. The time to conservative treatment before surgical intervention was 20 ± 9.2 days. In three cases, the disc cysts were located in L4/5 and in six cases the lesions were located in L5/S1. Intervertebral disc cyst interventions included foraminal scope (three cases), open discectomy (three cases), conservative treatment with a quadrant channel (one case) and CT-guided puncture (one case). All patients fully recovered after surgery and the mean follow-up time was 3.5 ± 2.1 years. A literature review identified 14 relevant articles that reported 43 PDP cases of PDP. CONCLUSION: PDP occurs in Asian males with mild intervertebral disc degeneration and occurs 1 month after discectomy. Treatment should be based on specific patient scenarios. Conservative treatment is necessary and surgery should be performed with caution.

Application of Laminoplasty Combined with ARCH Plate in the Treatment of Lumbar Intraspinal Tumors.

OBJECTIVE: To investigate the bone fusion and clinical effect of laminoplasty combined with ARCH plate fixation in the treatment of lumbar intraspinal tumors. METHODS: This was a clinical study. From June 2017 to January 2019, 24 patients (seven males and 17 females, average age 40 ± 16 years) with lumbar intraspinal tumors underwent laminoplasty combined with ARCH plate fixation in our hospital. The bone fusion was evaluated by X-ray and computed tomography (CT) scans that were taken 15.2 ± 2.17 months postoperatively. Each segment showed a bone bridge on one side, which was classified as "segmental partial fusion." Each segment showed bilateral bone bridges, which were classified as "segmental complete fusion". When all segments of the patient showed bilateral bone bridging so that the replanted lamina and the host lamina became a unit on the CT scan, it was defined as "complete fusion". In addition, the operation time and blood loss were recorded. Fisher's exact test was used to analyze the potential influencing factors of bone healing, including age (≤40 years vs >40 years), gender, number of operated levels (single vs two). Paired t-test was used to analyze pre- and postoperative Oswestry Disability Index (ODI) scale and low back and leg pain visual analog scale (VAS). RESULTS: A total of 33 segments of laminoplasty were successfully performed in 24 patients. The average operation time was 128 ± 18 minutes. The average blood loss was 110 ± 19 mL. All patients were followed up at least 12 months after operation (average, 15.2 ± 2.17 months). At the final follow-up, according to the definition of this study, the proportion of "segmental partial fusion" and "segmental complete fusion" were 30.3% (10/33) and 69.7% (23/33), respectively. And the proportion of patients with "complete fusion" was 70.8% (17/24). Age, gender, and number of operated levels were not associated with the fusion (P = 1.0, 0.37, and 0.06, respectively). ODI and VAS were much better at 1 month after operation and the final follow-up than those before the operation (P < 0.01). At 6 months after operation, the results of magnetic resonance imaging (MRI) showed that the supraspinous ligament was repaired, and there were no complications, such as spinal epidural scar recompression. CONCLUSIONS: Laminoplasty combined with ARCH plate was a better surgical method, and 70.8% of the patients showed complete bone fusion and there was no case of bilateral nonunion.