10-Year Clinical, Functional, and X-ray Follow-Up Evaluation of a Novel Posterior Percutaneous Screw-Rod Instrumentation Technique for Single-Level Pyogenic Spondylodiscitis.

Medical treatment with antibiotic therapy remains the mainstay of treatment for pyogenic spondylodiscitis (PS). Nevertheless, orthopaedic treatment is also very important in relieving pain, preventing neurological damage, and avoiding development of spinal deformities (e.g., scoliosis, kyphosis) due to spinal instability. Rigid thoracolumbosacral orthosis (TLSO) bracing is often needed in patients with PS, and average duration of treatment of 3 to 4 months. However, TLSO bracing can be poorly tolerated and limit ability of the patient to go back to a normal life. In 2004 our group developed an alternative surgical treatment to TLSO bracing by percutaneous posterior screw-rod bridge instrumentation of the infected level. This treatment allows early and free mobilization of the patients and is associated with faster recovery, lower pain scores and improved quality of life as previously reported. Herein, we report the clinical outcome of the first 3 patients who have completed the 10 years follow-up mark after the procedure. A case report is also described and details of the procedure are provided.

Influences of circulatory factors on intervertebral disc aging phenotype.

Whether disc aging is influenced by factors beyond its local environment is an important unresolved question. Here we performed heterochronic parabiosis in mice to study the effects of circulating factors in young and old blood on age-associated intervertebral disc degeneration. Compared to young isochronic pairs (Y-Y), young mice paired with old mice (Y-O) showed significant increases in levels of disc MMP-13 and ADAMTS4, aggrecan fragmentation, and histologic tissue degeneration, but negligible changes in cellular senescence markers (p16INK4a, p21Cip1). Compared to old isochronic pairs (O-O), old mice paired with young mice (O-Y) exhibited a significant decrease in expression of cellular senescence markers (p16, p21, p53), but only marginal decreases in the levels of disc MMP-13 and ADAMTS4, aggrecan fragmentation, and histologic degeneration. Thus, exposing old mice to young blood circulation greatly suppressed disc cellular senescence, but only slightly decreased disc matrix imbalance and degeneration. Conversely, exposing young mice to old blood accelerated their disc matrix imbalance and tissue degeneration, with little effects on disc cellular senescence. Thus, non-cell autonomous effects of circulating factors on disc cellular senescence and matrix homeostasis are complex and suggest that disc matrix homeostasis is modulated by systemic factors and not solely through local disc cellular senescence.

ATM is a key driver of NF-κB-dependent DNA-damage-induced senescence, stem cell dysfunction and aging.

NF-κB is a transcription factor activated in response to inflammatory, genotoxic and oxidative stress and important for driving senescence and aging. Ataxia-telangiectasia mutated (ATM) kinase, a core component of DNA damage response signaling, activates NF-κB in response to genotoxic and oxidative stress via post-translational modifications. Here we demonstrate that ATM is activated in senescent cells in culture and murine tissues from Ercc1-deficient mouse models of accelerated aging, as well as naturally aged mice. Genetic and pharmacologic inhibition of ATM reduced activation of NF-κB and markers of senescence and the senescence-associated secretory phenotype (SASP) in senescent Ercc1-/- MEFs. Ercc1-/Δ mice heterozygous for Atm have reduced NF-κB activity and cellular senescence, improved function of muscle-derived stem/progenetor cells (MDSPCs) and extended healthspan with reduced age-related pathology especially age-related bone and intervertebral disc pathologies. In addition, treatment of Ercc1-/∆ mice with the ATM inhibitor KU-55933 suppressed markers of senescence and SASP. Taken together, these results demonstrate that the ATM kinase is a major mediator of DNA damage-induced, NF-κB-mediated cellular senescence, stem cell dysfunction and aging and thus represents a therapeutic target to slow the progression of aging.

Adenoviral gene transfer of a single-chain IL-23 induces psoriatic arthritis-like symptoms in NOD mice.

Previously, we demonstrated that intratumoral delivery of adenoviral vector encoding single-chain (sc)IL-23 (Ad.scIL-23) was able to induce systemic antitumor immunity. Here, we examined the role of IL-23 in diabetes in nonobese diabetic mice. Intravenous delivery of Ad.scIL-23 did not accelerate the onset of hyperglycemia but instead resulted in the development of psoriatic arthritis. Ad.scIL-23-treated mice developed erythema, scales, and thickening of the skin, as well as intervertebral disc degeneration and extensive synovial hypertrophy and loss of articular cartilage in the knees. Immunological analysis revealed activation of conventional T helper type 17 cells and IL-17-producing γδ T cells along with a significant depletion and suppression of T cells in the pancreatic lymph nodes. Furthermore, treatment with anti-IL-17 antibody reduced joint and skin psoriatic arthritis pathologies. Thus, these Ad.scIL-23-treated mice represent a physiologically relevant model of psoriatic arthritis for understanding disease progression and for testing therapeutic approaches.-Flores, R. R., Carbo, L., Kim, E., Van Meter, M., De Padilla, C. M. L., Zhao, J., Colangelo, D., Yousefzadeh, M. J., Angelini, L. A., Zhang, L., Pola, E., Vo, N., Evans, C. H., Gambotto, A., Niedernhofer, L. J., Robbins, P. D. Adenoviral gene transfer of a single-chain IL-23 induces psoriatic arthritis-like symptoms in NOD mice.

Teriparatide anabolic therapy as potential treatment of type II dens non-union fractures.

Odontoid fractures account for 5% to 15% of all cervical spine injuries and 1% to 2% of all spine fractures. Type II fractures are the most common fracture pattern in elderly patients. Treatment (rigid and non-rigid immobilization, anterior screw fixation of the odontoid and posterior C1-C2 fusion) remains controversial and represents a unique challenge for the treating surgeon. The aims of treatment in the elderly is to quickly restore pre-injury function while decreasing morbidity and mortality associated with inactivity, immobilization with rigid collar and prolonged hospitalization. Conservative treatment of type II odontoid fractures is associated with relatively high rates of non-union and in a few cases delayed instability. Options for treatment of symptomatic non-unions include surgical fixation or prolonged rigid immobilization. In this report we present the case of a 73-year-old woman with post-traumatic odontoid non-union successfully treated with Teriparatide systemic anabolic therapy. Complete fusion and resolution of the symptoms was achieved 12 wk after the onset of the treatment. Several animal and clinical studies have confirmed the potential role of Teriparatide in enhancing fracture healing. Our case suggests that Teriparatide may have a role in improving fusion rates of C2 fractures in elderly patients.

The Achilles' heel of senescent cells: from transcriptome to senolytic drugs.

The healthspan of mice is enhanced by killing senescent cells using a transgenic suicide gene. Achieving the same using small molecules would have a tremendous impact on quality of life and the burden of age-related chronic diseases. Here, we describe the rationale for identification and validation of a new class of drugs termed senolytics, which selectively kill senescent cells. By transcript analysis, we discovered increased expression of pro-survival networks in senescent cells, consistent with their established resistance to apoptosis. Using siRNA to silence expression of key nodes of this network, including ephrins (EFNB1 or 3), PI3Kδ, p21, BCL-xL, or plasminogen-activated inhibitor-2, killed senescent cells, but not proliferating or quiescent, differentiated cells. Drugs targeting these same factors selectively killed senescent cells. Dasatinib eliminated senescent human fat cell progenitors, while quercetin was more effective against senescent human endothelial cells and mouse BM-MSCs. The combination of dasatinib and quercetin was effective in eliminating senescent MEFs. In vivo, this combination reduced senescent cell burden in chronologically aged, radiation-exposed, and progeroid Ercc1(-/Δ) mice. In old mice, cardiac function and carotid vascular reactivity were improved 5 days after a single dose. Following irradiation of one limb in mice, a single dose led to improved exercise capacity for at least 7 months following drug treatment. Periodic drug administration extended healthspan in Ercc1(-/∆) mice, delaying age-related symptoms and pathology, osteoporosis, and loss of intervertebral disk proteoglycans. These results demonstrate the feasibility of selectively ablating senescent cells and the efficacy of senolytics for alleviating symptoms of frailty and extending healthspan.

Is posterior percutaneous screw-rod instrumentation a safe and effective alternative approach to TLSO rigid bracing for single-level pyogenic spondylodiscitis? Results of a retrospective cohort analysis.

BACKGROUND CONTEXT: Currently, treatment for patients diagnosed with noncomplicated (ie, known infectious agent, no neurologic compromise, and preserved spinal stability) pyogenic spondylodiscitis (PS) is based on intravenous antibiotics and rigid brace immobilization. Since January 2010, we started offering our patients percutaneous posterior screw-rod instrumentation as an alternative approach to rigid bracing. Supposed benefits of posterior percutaneous instrumentation over rigid bracing are earlier free mobilization, increased comfort, and faster recovery. PURPOSE: To evaluate safety and effectiveness of posterior percutaneous spinal instrumentation for single-level PS and compare clinical and quality-of-life outcomes with standard thoracolumbosacral orthosis (TLSO) rigid bracing. STUDY DESIGN/SETTING: Retrospective observational cohort study. PATIENT SAMPLE: Twenty-seven patients consecutively diagnosed with single-level noncomplicated lower thoracic or lumbar PS from January 2010 to December 2011. OUTCOME MEASURES: Healing rate, healing time, and changes in segmental kyphosis Cobb angle were compared in the two treatment groups. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and complete blood count at regular time points until complete healing were also obtained. Self-report measures included Visual Analog Scale (VAS), Short-Form 12 (SF-12), and EuroQol five-dimension (EQ-5D) questionnaires. METHODS: At enrollment, patients were offered to choose between 24/7 TLSO rigid bracing for 3 to 4 months and bridging posterior percutaneous screw-rod instrumentation followed by soft bracing for 4 weeks after surgery. All patients underwent antibiotic therapy accordingly to isolated infectious agents. Patients were seen in the clinic at 1, 3, 6, and 9 months, and ESR, CRP, complete blood count, VAS, SF-12, and EQ-5D questionnaires were obtained. Segmental kyphosis was measured at diagnosis and at 9 months follow-up. Two-way repeated-measures analysis of variance was used to assess group and time differences across time points. RESULTS: Fifteen patients chose conservative treatment, whereas 12 patients chose surgical treatment. Complete infection healing was achieved in all patients with no significant differences in healing time (p<.366). C-reactive protein and ESR levels decreased in both groups accordingly with positive response to therapy with no significant differences. Surgically treated patients had significantly lower VAS scores at 1 month (2.76±0.80 vs. 5.20±1.21, p<.001) and 3 months (2.31±0.54 vs. 2.85±0.54, p<.016) post-diagnosis over TLSO patients. Moreover, surgery patients also showed steeper and statistically significant improvements in SF-12 scores over TLSO patients at 1, 3, and 6 months post-diagnosis (p<.012); no significant differences were detected at the other time points. EuroQol five-dimension index was significantly higher in surgery patients at 1 month (0.764±0.043 vs. 0.458±0.197, p<.001) and 3 months (0.890±0.116 vs. 0.688±0.142, p<.001); no significant changes were observed in segmental pre- and posttreatment kyphosis between the two groups. No instrumentation-related complications were observed in any patient. CONCLUSIONS: Posterior percutaneous spinal instrumentation is a safe, feasible, and effective procedure in relieving pain, preventing deformity, and neurologic compromise in patients affected by noncomplicated lower thoracic (T9-T12) or lumbar PS. Posterior instrumentation did not offer any advantage in healing time over TLSO rigid bracing because infection clearance is strongly dependent on proper antibiotic therapy. Nevertheless, surgical stabilization was associated with faster recovery, lower pain scores, and improved quality of life compared with TLSO conservative treatment at 1, 3, and 6 months after treatment.

Severe spinal deformity and multiple vertebral collapses in juvenile Cushing Syndrome: a case report.

Cushing's Syndrome (CS) is rare in adolescence but the pathological effects of excessive circulating glucocorticoids concentration on bone during the developmental age still represent a challenge for orthopedists. Only few reports describe the gravity of early developed damages of spine in young affected by CS. A 18-years-old woman suffering from Cushing's Disease presented after many years treatment of the primary disease referring severe back pain and worsening back deformity. Radiological investigations showed vertebral collapses a devastating thoraco-lumbar scoliosis of 80° Cobb. Lumbar dual X-ray absorptiometry Z-score values were very low and consistent with severe osteoporosis. The patient was treated with bracing, antiresorptive therapy, calcium and vitamin D supplementation, and followed-up with imaging investigations to screen for further fractures. The bone mineral density will be monitored until its normalization will allow to plane surgical treatment in case of progression of spinal deformity and collapses. Early diagnosis and treatment of hypercortisolism, periodical clinical and radiographic follow-up, and treatment for the bone damage are mandatory to prevent the devastating sequelae of secondary osteoporosis.