Can We Rely on Prophylactic Two-Level Vertebral Cement Augmentation in Long-Segment Adult Spinal Deformity Surgery to Reduce the Incidence of Proximal Junctional Complications?

Background and Objectives: Proximal junctional kyphosis (PJK) and failure (PJF), the most prevalent complications following long-segment thoracolumbar fusions for adult spinal deformity (ASD), remain lacking in defined preventive measures. We studied whether one of the previously reported strategies with successful results-a prophylactic augmentation of the uppermost instrumented vertebra (UIV) and supra-adjacent vertebra to the UIV (UIV + 1) with polymethylmethacrylate (PMMA)-could also serve as a preventive measure of PJK/PJF in minimally invasive surgery (MIS). Materials and Methods: The study included 29 ASD patients who underwent a combination of minimally invasive lateral lumbar interbody fusion (MIS-LLIF) at L1-2 through L4-5, all-pedicle-screw instrumentation from the lower thoracic spine to the sacrum, S2-alar-iliac fixation, and two-level balloon-assisted PMMA vertebroplasty at the UIV and UIV + 1. Results: With a minimum 3-year follow-up, non-PJK/PJF group accounted for fifteen patients (52%), PJK for eight patients (28%), and PJF requiring surgical revision for six patients (21%). We had a total of seven patients with proximal junctional fracture, even though no patients showed implant/bone interface failure with screw pullout, probably through the effect of PMMA. In contrast to the PJK cohort, six PJF patients all had varying degrees of neurologic deficits from modified Frankel grade C to D3, which recovered to grades D3 and to grade D2 in three patients each, after a revision operation of proximal extension of instrumented fusion with or without neural decompression. None of the possible demographic and radiologic risk factors showed statistical differences between the non-PJK/PJF, PJK, and PJF groups. Conclusions: Compared with the traditional open surgical approach used in the previous studies with a positive result for the prophylactic two-level cement augmentation, the MIS procedures with substantial benefits to patients in terms of less access-related morbidity and less blood loss also provide a greater segmental stability, which, however, may have a negative effect on the development of PJK/PJF.

Lumbar lordosis restoration by minimally invasive short-segment fusion with anterior column realignment for adult spinal deformity: minimum 2-year follow-up.

OBJECTIVE: The efficacy of anterior column realignment (ACR) remains relatively unclear, possibly because some safety concerns have limited its adoption and extensive evaluation. The authors aimed to study whether a minimally invasive surgery (MIS) triad consisting of ACR, lateral lumbar interbody fusion, and percutaneous pedicle screw fixation in a select group of adult spinal deformity (ASD) patients helps shorten fusion length without compromising clinical and radiographic outcomes over a minimum 2-year follow-up period. METHODS: A series of 61 ASD patients (mean age 72.8 years) with pelvic incidence (PI) - lumbar lordosis (LL) (PI-LL) mismatch > 10° underwent the short-segment MIS triad (mean fusion length 3.0 levels) as a single-stage operation with a mean operative time and estimated blood loss of 157 minutes and 127 mL, respectively. Exclusion criteria were 1) thoracic scoliosis as the main deformity, 2) thoracolumbar junction kyphosis > 25°, 3) ankylosed facet joints, and 4) previous spinal fusion surgery. Seven patients, who needed fusion to be extended to S1, underwent mini-open transforaminal lumbar interbody fusion at L5-S1. RESULTS: The segmental disc angle at the ACR level more than quintupled, averaging from 2.9° preoperatively to 18.9° at the latest follow-up (p < 0.0001). LL, in turn, nearly doubled from 17.0° to 32.8° (p < 0.0001) and PI-LL decreased by nearly half from 28.8° to 13.2° (p < 0.0001). At the same time, other spinopelvic deformity parameters as well as Oswestry Disability Index (ODI) scores significantly improved. Patients were divided into two groups at the latest postoperative evaluation: 36 patients whose PI-LL improved to < 10° and 25 patients who maintained a PI-LL mismatch > 10°. Binary logistic regression revealed preoperative PI-LL mismatch as the only factor that significantly influenced this dichotomous separation postoperatively. Receiver operating characteristic curve analysis identified the critical preoperative mismatch of 26.4° with 68% sensitivity and 84% specificity. Despite this different radiographic consequence, the two groups had an equally successful clinical outcome with no significant difference in ODI scores. CONCLUSIONS: As long as the ASD characteristics are consistent with the authors' exclusion criteria, the short-segment MIS triad served as an excellent surgical option in the patients with preoperative PI-LL mismatch < 26.4°, but the technique also worked well even in those with a mismatch > 26.4°, although ideal spinopelvic alignment targets were not necessarily achieved in these patients.

New Effective Intraoperative Techniques for the Prevention of Coronal Imbalance after Circumferential Minimally Invasive Correction Surgery for Adult Spinal Deformity.

This study aimed to devise measures and investigate their effect on coronal imbalance (CI) after circumferential minimally invasive correction surgery (CMIS) with lateral lumbar interbody fusion and percutaneous pedicle screw for adult spinal deformity (ASD). A total of 115 patients with ASD who underwent CMIS from the lower thoracic spine to the ilium were included. Patients were stratified based on the distance between the spinous process of the upper instrumented vertebra and central sacrum vertical line (UIV-CSVL) after the first intraoperative rod application into groups P (UIV-CSVL > 10 mm, n = 50) and G (UIV-CSVL < 10 mm, n = 65). Measures to correct postoperative CI introduced during surgery, preoperative and postoperative UIV-CSVL, and changes in UIV-CSVL after various measures (ΔUIV-CSVL) were investigated in group P. Rod rotation (RR), S2 alar-iliac screw distraction (SD), and kickstand-rod (KR) technique were performed in group P. Group P was further divided into group RR (n = 38), group SD (RR and SD) (n = 7), and group KR (RR and KR) (n = 5); the ΔUIV-CSVLs were 13.9 mm, 20.1 mm, and 24.4 mm in these three groups, respectively. Postoperative C7-CSVL < 10 mm was achieved in all three correction groups. In conclusion, our measures enabled sufficient correction of the UIV-CSVL and are useful for preventing CI after CMIS for ASD.

Enhancement of skin permeation of fluorescein isothiocyanate-dextran 4 kDa (FD4) and insulin by thermalporation.

Thermalporation has gained attention as a physical means to enhance skin permeation by creating micropores in the primary skin barrier, stratum corneum, which allows much higher permeation of middle and high molecular weight biopharmaceuticals. In the present study, a PassPort® system (PS) was used as a thermalporation device, and the obtained change in permeation resistance of drugs was evaluated using a parallel skin permeation-resistance model. In addition, the blood concentration-time profile after topical application of insulin was also investigated with the PS treatment. Fluorescein isothiocyanate-dextran (FD-4) and insulin were used as model middle molecular weight drugs. Micropores created by the PS treatment were measured using an optical microscope. An in vitro skin permeation and an in vivo pharmacokinetics experiments were done with FD-4 and insulin, respectively. Barrier function recovery after the PS treatment was evaluated with changes in the electrical skin resistance. About 960-fold higher skin permeation of FD-4 was observed by PSs treatment (4 milliseconds (ms), 200 micropores/cm2). A gradually increased blood concentration of insulin was observed by the PSs treatment, and the relative bioavailability of insulin was 21.1% compared with subcutaneous injection. Skin resistance value was dramatically decreased immediately after the PS treatment, but its value was turned into the initial one by 12 h. The thermalporation is effective for improving skin permeation of FD-4 and transdermal absorption of insulin. These results suggested that the PS treatment may be utilized to increase the skin permeation of topically applied FD-4 and insulin.

The complete mitochondrial genome of the gnomefish Scombrops boops (Teleostei, Perciformes, Scombropidae) from the Pacific Ocean off the Japanese Islands.

The complete mitochondrial genome of the gnomefish Scombrops boops was determined by a PCR-based method. The total length of mitochondrial DNA (mtDNA) was 16,517 bp, including 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and one control region. The mitochondrial gene arrangement of the gnomefish mtDNA was identical to those of typical teleosts. This is the first report of the complete mitochondrial genome of a member of the Scombropidae family and will be useful for the development of molecular tools for ecological research.

An angiogenesis inhibitor E7820 shows broad-spectrum tumor growth inhibition in a xenograft model: possible value of integrin alpha2 on platelets as a biological marker.

We reported previously that an angiogenesis inhibitor, E7820, inhibits in vitro tube formation of human umbilical vein endothelial cell through the suppression of integrin alpha2 expression. Here we describe the antiangiogenic and antitumor effects of E7820 in mice and discuss the feasibility of using platelet integrin alpha2 expression on platelets as a biological marker of the efficacy of E7820. Oral administration of E7820 significantly inhibited basic fibroblast growth factor-induced angiogenesis in Matrigel implants and human colon WiDr tumor-induced angiogenesis in a dorsal air sac model. Twice-daily treatment with E7820 clearly inhibited the s.c. tumor growth of seven tumor cell lines derived from human colon, breast, pancreas, and kidney, and completely suppressed the growth of human pancreatic KP-1 and human colon LoVo cell lines. Moreover, E7820 significantly inhibited the growth of KP-1 and human colon tumor Colo320DM cells orthotopically implanted in the pancreas and cecum, respectively. The efficacy of E7820 was comparable in the s.c. and orthotopic transplantation models. Immunohistochemical analyses using anti-CD31 antibody showed that E7820 significantly reduced microvessel density in orthotopically implanted KP-1 tumor. E7820 reduced integrin alpha2 expression on a megakaryocytic cell line, Dami cells, induced by phorbol 12-myristate 13-acetate treatment. It also decreased the expression level of integrin alpha2 on platelets withdrawn from mice bearing s.c. KP-1 tumor at a dosage close to that affording antitumor activity. These data demonstrate that E7820 showed a broad-spectrum antitumor effect in mice through inhibition of angiogenesis and indicate that the decrease of integrin alpha2 on platelets might serve as a biological marker for the antitumor efficacy of E7820.