Suspected allergy to titanium after anterior cervical discectomy and fusion using a Zero-P device: a case report.

PURPOSE: Cases of allergy to large surgical implants have been reported. However, few studies have reported allergy to small titanium-containing implants (e.g. Zero-P device). METHODS: We reported the case of a 51-year old male patient who underwent the anterior cervical discectomy and fusion (ACDF) procedure using a Zero-P device and exhibited allergic symptoms 1 month after the surgery. RESULTS: The allergic symptoms included intermittent tingling and itches in the throat induced by speaking. Systemic rashes over the skin surface and congestion of the eyeball, and dysphagia were also present. Anti-allergic treatment did not resolve the symptoms. Patch tests revealed negative reactions to the rested reagents including titanium. Radiographic results showed solid bone fusion and no signs of chronic inflammation or hypotoxic infection in the surrounding tissues. Upon the patient's request, we removed the titanium screws and plate of the Zero-P device. No allergic reactions were observed after the surgery and at a 6-month follow-up. CONCLUSIONS: Even with a small implant such as the Zero-P device, allergy to titanium may still occur. This case demonstrated the need to screen for the presence of allergy to metals including titanium before the surgery.

Optimization, characterization and evaluation of ZnO/polyvinylidene fluoride nanocomposites for orthopedic applications: improved antibacterial ability and promoted osteoblast growth.

Herein, electrospun zinc oxide nanoparticle/poly (vinylidene fluoride) (ZnONP/PVDF) composite fiber membranes were designed, fabricated, and tested for improved orthopedic applications. A single factor screening study was conducted to determine the optimal ZnONP/PVDF formulation based on osteoblast (bone forming cells) proliferation and antibacterial properties. Further, ZnONP/PVDF materials were characterized for their morphology, crystallinity, roughness, piezoelectric properties, and chemistry to understand such cell results. The optimal concentration of high molecular weight PVDF (18%, w/v) and a low concentration of ZnONPs (1 mg/ml) were identified for electrospinning at room temperature in order to inhibit bacterial colonization (without resorting to antibiotic use) and promote osteoblast proliferation. Compared to no ZnO/PVDF scaffold without Piezo-excited group,the study showed that on the 1 mg/ml ZnO/PVDF scaffolds with piezo-excitation, the density of SA and E.coli decreased by 68% and 56%.The density of osteoblasts doubled within three days(compared to the control). In summary, ZnONP/PVDF composite fiber membranes were formulated by electrospinning showing an exceptional ability to eliminate bacteria colonization while at the same time promote osteoblast functions and, thus, they should be further studied for a wide range of orthopedic applications.

Standalone oblique lateral interbody fusion vs. combined with percutaneous pedicle screw in spondylolisthesis.

BACKGROUND: To compare standalone oblique lateral interbody fusion (OLIF) vs. OLIF combined with posterior bilateral percutaneous pedicle screw fixation (OLIF combined) for the treatment of lumbar spondylolisthesis. METHODS: This was a retrospective study of patients who underwent standalone OLIF or combined OLIF between 07/2014 and 08/2017 at two hospitals in China. Direct decompressions were not performed. Visual analog scale (VAS), Oswestry Disability Index (ODI), satisfaction rate, anterior/posterior disc heights (DH), foraminal height (FH), foraminal width (FW), cage subsidence, cage retropulsion, fusion rate, and complications were analyzed. All imaging examinations were read independently by two physicians and the mean measurements were used for analysis. RESULTS: A total of 73 patients were included: 32 with standalone OLIF and 41 with combined OLIF. The total complication rate was 25.0% with standalone OLIF and 26.8% with combined OLIF. There were no differences in VAS and ODI scores by 2 years of follow-up, but the scores were better with standalone OLIF at 1 week and 3 months (P < 0.05). PDH and FW was smaller in the combined OLIF group compared with the standalone OLIF group before and after surgery (all P < 0.05). There were significant differences in FH before surgery and at 1 week and 3 months between the two groups (all P < 0.05), but the difference disappeared by 2 years (P = 0.111). Cage subsidence occurred in 7.3% (3/41) and 7.3% (3/41) of the patients at 3 and 24 months, respectively, in the combined OLIF group, compared with 6.3% (2/32) and 15.6% (5/32), respectively, in the standalone OLIF group at the same time points (P = 0.287). There was no cage retropulsion in both groups at 2 years. The fusion rate was 85.4%(35/41) in the combined OLIF group and 84.4% (27/32) in the standalone OLIF group at 3 months(P = 0.669). At 24 months, the fusion rate was 100.0% in the combined OLIF group and 93.8% (30/32) in the standalone OLIF group (P = 0.066). CONCLUSION: Standalone OLIF may achieve equivalent clinical and radiological outcomes than OLIF combined with fixation for spondylolisthesis. The rate of complications was similar between the two groups. Patients who are osteoporotic might be better undergoing combined rather than standalone OLIF. The possibilty of proof lies within a future prospective study, preferably an RCT.

Dynamic Bioreactor Culture for Infiltration of Bone Mesenchymal Stem Cells within Electrospun Nanofibrous Scaffolds for Annulus Fibrosus Repair.

OBJECTIVE: To compare the ability of three culture strategies of static culture, intermittent centrifugal culture and dynamic bioreactor culture in promoting the infiltration of bone marrow mesenchymal stem cells (BMSCs) throughout electrospun nanoporous aligned nanoyarn scaffold (AYS). METHODS: AYS was constructed by the method of conjugated electrospinning, using the blended solution of poly (L-lactide-co-caprolactone) (P (LLA-CL)) and gelatin. Then the bone marrow mesenchymal stem cells (BMSCs) were transplanted on the scaffolds. Culture the scaffold-cells using three methods of static culture, intermittent centrifugal culture and dynamic bioreactor culture. After 7 and 14 days in culture, the infiltration depth of the cells were observed and measured by hematoxylin and eosin (HE) or 4', 6-diamidino-2-phenylindole (DAPI) staining. RESULT: In the current study, on the 7th day, the BMSCs in the scaffolds of static culture group, intermittent centrifugal culture group, and dynamic bioreactor culture group infiltrated to an average depth of 11.88 ± 1.82 µm, 21.17 ± 13.17 µm, and 26.27 ± 7.42 µm, respectively. There were differences between the bioreactor culture group with the static culture group and the intermittent centrifugal culture group. On the time point of 14 days, the depth of infiltration of BMSCs in dynamic bioreactor culture was the most (115.13 ± 25.44 µm, P < 0.05), and the infiltration of the cells in the intermittent centrifugal culture group was 42.53 ± 13.07 µm, deeper than that of the static culture group (24.53 ± 6.06, P < 0.05). CONCLUSION: Dynamic bioreactor culture may be a preferred method for tissue engineering approaches involving scaffolds with a low porosity, such as those needed for repair of the annulus fibrosus (AF).

Quantitative analysis of paraspinal muscle atrophy after oblique lateral interbody fusion alone vs. combined with percutaneous pedicle screw fixation in patients with spondylolisthesis.

BACKGROUND: There is no available literature for comparison on muscle atrophy between the "stand-alone" oblique lateral interbody fusion (OLIF) and regular OLIF (i.e., combined with percutaneous pedicle screws fixation (PPSF) in patients with spondylolisthesis). This study aimed to identify changes in back muscle atrophy between the two surgeries. METHODS: This was a retrospective cohort study of patients who underwent OLIF or OLIF+PPSF at Beijing Jishuitan Hospital and Shanghai ChangZheng Hospital between 07/2014 and 10/2017. Computed tomography (CT) was used to measure functional cross-sectional area (FCSA) and fat infiltration percentage (FIP) of the multifidus and erector spinae before and 24 months after surgery. RESULT: There were no differences in FCSA and FIP between OLIF (n = 32) and OLIF+PPSF (n = 41) groups before surgery. In the OLIF group, the multifidus and erector spinae FCSA and FIP did not change at 24 months (FCSA: multifidus: from 8.59 ± 1.76 to 9.39 ± 1.74 cm2, P = 0.072; erector spinae: from 13.32 ± 1.59 to 13.55 ± 1.31 cm2, P = 0.533) (FIP: multifidus: from 15.91 ± 5.30% to 14.38 ± 3.21%, P = 0.721; erector spinae: from 11.63 ± 3.05% to 11.22 ± 3.12%, P = 0.578). In the OLIF+PPSF group, the multifidus and erector spinae FCSA decreased (multifidus: from 7.72 ± 2.69 to 5.67 ± 1.71 cm2, P < 0.001; erector spinae: from 12.60 ± 2.04 to 10.15 ± 1.82 cm2, P < 0.001), while the FIP increased (multifidus: from 16.13 ± 7.01% to 49.38 ± 20.54%, P < 0.001; erector spinae: from 11.93 ± 3.22% to 22.60 ± 4.99%, P < 0.001). The differences of FCSA and FIP between the two groups at 24 months were significant (all P < 0.001). The patients in the standalone OLIF group had better VAS back pain, and JOA scores than the patients in the OLIF combined group (all P < 0.05) at 1 week and 3 months after surgery. There were two cases (4.9%) of adjacent segment degeneration in the OLIF combined group, while there was no case in the OLIF alone group. CONCLUSIONS: Standalone OLIF had better clinical outcomes at 1 week and 3 months than OLIF+PPSF in patients with spondylolisthesis. OLIF may not result in paraspinal muscle atrophy at 24 months after surgery.

Unilateral Versus Bilateral Percutaneous Pedicle Screw Fixation in Oblique Lumbar Interbody Fusion.

OBJECTIVE: To compare clinical and radiologic outcomes of unilateral pedicle screw (UPS) and bilateral pedicle screw (BPS) fixations after single-level oblique lateral interbody fusion procedures. METHODS: This retrospective study included 74 patients receiving single-level oblique lateral interbody fusion at L3-4 or L4-5 (June 2014 to June 2017). These patients were divided into BPS (n = 36) and UPS (n = 38) groups. Perioperative outcomes included operative time, blood loss, medical expenses, and complication rates. Radiologic outcomes included fusion rates and cage subsidence rates. Clinical outcomes included disability measured by the Oswestry Disability Index and pain measured by the visual analog scale. RESULTS: The operative time was significantly shorter in the UPS group (76.2 ± 4.4 minutes) compared with the BPS group (127.0 ± 5.6 minutes, P < 0.001). There was a significant between-group difference in medical expenses ($11,044.8 ± $470.7 in UPS group vs. $15,018.4 ± $547.1 in BPS, P < 0.001). Blood loss and hospital stay did not differ between groups. Oswestry Disability Index and visual analog scale scores significantly decreased in both groups at different time points postoperatively compared with preoperatively. The UPS group had lower Oswestry Disability Index and visual analog scale scores than the BPS group at 7 days postoperatively, but no between-group difference was found after 1-month follow-up. Fusion rate was 86.8% in UPS group and 91.7% in BPS group (P > 0.05). Cage subsidence rates did not differ between groups. CONCLUSIONS: Oblique lateral interbody fusion with UPS fixation is an effective and reliable option for single-level lumbar diseases. Compared with BPS fixation, it resulted in less blood loss, required less operative time, and had comparable effects on radiologic and clinical outcomes.

Removal of calcified lumbar disc herniation with endoscopic-matched ultrasonic osteotome - Our preliminary experience.

Objective: To evaluate the clinical efficacy, practicability, and safety of an ultrasonic osteotome for percutaneous transforaminal endoscopic discectomy (PTED) in patients with calcified lumbar disc herniation (CLDH).Methods: A total of 25 CLDH patients who underwent PTED at our department between December 2017 and August 2018 were analyzed retrospectively. Post-operative lumbar spine CT was used to evaluate residual calcification. Efficacy was evaluated by pre- and post-operative with the pain visual analog scale (VAS), Oswestry disability index (ODI), and the Modified MacNab Scale; the incidence of intra- and postoperative complications was also analyzed.Results: All procedures were successfully completed and none of the patients was lost to follow-up. Postoperative CT verified the successful removal of calcified protrusions. VAS and ODI scores improved significantly after surgery. Based on the Modified MacNab scale, >90% patients achieved good or excellent outcomes. There were no complications such as dural tear and infection. Seven patients had varying degrees of postoperative dysesthesia. One patient experienced recurrence of herniation within 1 week after operation; successful recovery was achieved after repeat PTED.Conclusions: Use of this ultrasonic osteotome for PTED facilitated effective removal of calcified disc protrusion, relieved nerve compression, and protected the adjacent neurovascular tissues. The instrument may help expand the indications for endoscopic surgery and avoid open surgery for some CLDH patients.

Advances in nanomedicine for the treatment of ankylosing spondylitis.

Ankylosing spondylitis (AS) is a complex disease characterized by inflammation and ankylosis primarily at the cartilage-bone interface. The disease is more common in young males and risk factors include both genetic and environmental. While the pathogenesis of AS is not completely understood, it is thought to be an immune-mediated disease involving inflammatory cellular infiltrates, and human leukocyte antigen-B27. Currently, there is no specific diagnostic technique available for this disease; therefore conventional diagnostic approaches such as clinical symptoms, laboratory tests and imaging techniques are used. There are various review papers that have been published on conventional treatment approaches, and in this review work, we focus on the more promising nanomedicine-based treatment modalities to move this field forward.

Dual targeting curcumin loaded alendronate-hyaluronan- octadecanoic acid micelles for improving osteosarcoma therapy.

INTRODUCTION: Curcumin (CUR) is a general ingredient of traditional Chinese medicine, which has potential antitumor effects. However, its use clinically has been limited due to its low aqueous solubility and bioavailability. In order to improve the therapeutic effect of CUR on osteosarcoma (i.e., bone cancer), a multifunctional micelle was developed here by combining active bone accumulating ability with tumor CD44 targeting capacity. METHODS: The CUR loaded micelles were self-assembled by using alendronate-hyaluronic acid-octadecanoic acid (ALN-HA-C18) as an amphiphilic material. The obtained micelles were characterized for size and drug loading. In addition, the in vitro release behavior of CUR was investigated under PBS (pH 5.7) medium containing 1% Tween 80 at 37℃. Furthermore, an hydroxyapatite (the major inorganic component of bone) affinity experiment was studied. In vitro antitumor activity was evaluated. Finally, the anti-tumor efficiency was studied. RESULTS: The size and drug loading of the CUR loaded ALN-HA-C18 micelles were about 118 ± 3.6 nm and 6 ± 1.2%, respectively. CUR was released from the ALN-HA-C18 micelles in a sustained manner after 12 h. The hydroxyapatite affinity experiment indicated that CUR loaded ALN-HA-C18 micelles exhibited a high affinity to bone. CUR loaded ALN-HA-C18 micelles exhibited much higher cytotoxic activity against MG-63 cells compared to free CUR. Finally, CUR loaded ALN-HA-C18 micelles effectively delayed anti-tumor growth properties in osteosarcoma bearing mice as compared with free CUR. CONCLUSION: The present study suggested that ALN-HA-C18 is a novel promising micelle for osteosarcoma targeting and delivery of the hydrophobic anticancer drug CUR.

Preliminary studies on the anti-osteoporosis activity of Baohuoside I.

The aim of the present study was to investigate the anti-osteoporotic activity of Baohuoside I, an active component of Herba Epimedii. Effects of Baohuoside I on the differentiation of BMSCs and the formation of adipocytes were evaluated using alkaline phosphatase staining and methylene blue staining method, respectively. Osteoporosis model was established in ovariectomized rats prior to the measurement of the serum SOD and MDA levels as well as the expression of inflammatory cytokines protein in the rats' tissues after treatment with Baohuoside I using ELISA assay kits. The estrogen-like effect of Baohuoside I was also measured on HeLa cells. The positive rates of ALP staining in Baohuoside I groups were significantly higher (p < 0.01) compared with the normal group, with no obvious adipocyte formation observed in the groups that received Baohuoside I treatments. The levels of inflammatory markers (IL-1ß, TNF-α, IL-6 and IL-8) in the treated groups were significantly lower (p < 0.05) than in the model group. Likewise, the treated groups exhibited a significantly higher (p < 0.05) serum levels of MDA compared with the model group, while SOD levels were markedly lower (p < 0.05) in a dose-dependent fashion. Baohuoside I showed no estrogen-like effect on HeLa cells upon treatment with the drug. Collectively, these results indicated that the anti-osteoporotic activity of Baohuoside I could be related to the induction of BMSCs differentiation into osteoblasts coupled with the inhibition of adipocyte formation, regulation of immune functions, and antioxidant activity.