White Cord Syndrome Following Cervical Surgery in a Patient With Klippel-Feil Syndrome: A Case Report.

White cord syndrome is a rare entity, as there are very few cases described in the current literature. Postoperative MRI examination reveals cord intrinsic changes, including edema and ischemia. It is also described as a reperfusion injury of the spinal cord. This report depicts a rare case of "white cord syndrome" with tetraplegia after posterior laminectomy and fusion of the cervical spine in a patient with Klippel-Feil syndrome. A 33-year-old male patient with Klippel-Feil syndrome presented to our department with cervical myelopathy, claudication, deteriorating neurological status, imbalance, and lower limb spasticity. Due to kyphotic malformation of the cervical spine, a two-stage surgical intervention was scheduled. The patient first underwent anterior spinal fusion of C4-C6 with corpectomy of C5, where many anatomical and visceral differentiations were signed, so the surgical team was enhanced by a vascular surgeon. The postoperative period was uneventful and the patient was discharged after a week of hospitalization without any neurological deterioration. A second surgical intervention was scheduled after two months where laminectomy of C5-C7 and posterior fusion of C5-T1 were carried out. However, due to intraoperative spinal instability and various anatomical spinal variations, a third surgery, which would be occipitocervical fusion, was decided as the final surgical solution. During the third surgical operation, after the laminectomy of C1 to C5 and the placement of the occipital plate, the screws, and the two rods in situ, complete nullification of the intraoperative neurophysiologic control was signed. The internal fixation was removed immediately, the wake-up test revealed tetraplegia below C5, and the patient was transferred to the ICU. Immediate MRI revealed no spinal cord hematoma; however, spinal cord edema was present. The patient underwent a tracheostomy and remained quadriplegic with a sensory level of T8 and motor level of C5 and was discharged to a rehabilitation center. The possibility of white cord syndrome should be explained by surgeons before any cervical decompression surgery, as well as a thorough neurological examination should be performed postoperatively. The early recognition and prompt management of white cord syndrome is recommended.

Impact of COVID-19 Pandemic on Fragility Fractures of the Hip: An Interrupted Time-Series Analysis of the Lockdown Periods in Western Greece and Review of the Literature.

Since December 2019, the COVID-19 pandemic has had a significant impact on healthcare systems worldwide, prompting policymakers to implement measures of isolation and eventually adopt strict national lockdowns, which affected mobility, healthcare-seeking behavior, and services, in an unprecedented manner. This study aimed to analyze the effects of these lockdowns on hip-fracture epidemiology and care services, compared to nonpandemic periods in previous years. We retrospectively collected data from electronic patient records of two major hospitals in Western Greece and included patients who suffered a fragility hip fracture and were admitted during the two 5-week lockdown periods in 2020, compared to time-matched patients from 2017-2019. The results showed a drop in hip-fracture incidence, which varied among hospitals and lockdown periods, and conflicting impacts on time to surgery, time to discharge after surgery, and total hospitalization time. The study also found that differences between the two differently organized units were exaggerated during the COVID-19 lockdown periods, highlighting the impact of compliance with social-distancing measures and the reallocation of resources on the quality of healthcare services. Further research is needed to fully understand the specific variations and patterns of geriatric hip-fracture care during emergency health crises characterized by limited resources and behavioral changes.

Bisphosphonate-loaded bone cement: Background, clinical indications and future perspectives.

Bisphosphonates represent an established treatment against bone resorption and osseous loss. Local application could help increase bone mineral density while minimizing their systemic use side-effects. Bone cement, used on a large scale in orthopedic surgery and a historically successful drug carrier, could represent an effective scaffold. The aim of this review was to investigate the alterations produced on the cement's structure and properties by this mixture, as well as its antiosteoporotic and antitumor effect. After a thorough research of articles, title screening and duplicate removal we retained 51 papers. Two independent authors performed abstract and full-text reading, finally leaving 35 articles included in this review. In the current literature, acrylic and calcium phosphate bone cement have been used as carriers. A combination with nitrogen-containing bisphosphonates, e.g., zoledronic acid, provokes modifications in terms of setting time prolongation and mechanical strength decline within acceptable levels, on the condition that the drug's quantity stays beneath a certain plateau. Bisphosphonates in bone cement seem to have a powerful anti-osteoclastic and osteogenic local impact as well as a direct cytotoxic effect against several neoplastic lesions. Further investigation on the subject is required, with specifically designed studies focusing on this method's advantages and potential clinical applications.

Association of vitamin D, BMD and knee osteoarthritis in postmenopausal women.

OBJECTIVES: The aim of this study was to analyze the association of knee OA with bone mineral density (BMD) and vitamin D serum levels in postmenopausal women. METHODS: A cross-sectional study including 240 postmenopausal women with knee OA was conducted. Demographic data were recorded along with balance and functionality scores. Knee OA severity was assessed by the radiological Kellgren & Lawrence scale. BMD and T-scores were calculated in hips and lumbar spine. Serum levels of vitamin D were also measured. RESULTS: High BMI (p<0.005), high number of children (p=0.022) and family history of hip fracture (p=0.011) are significantly associated with knee OA severity. Lumbar spine OP is negatively associated with knee OA (p<0.005). A significant difference was detected between vitamin D deficiency and severe knee OA, adjusted for BMD [OR (95%CI); 3.1 (1.6-6.1), p=0.001]. BMD does not affect the relationship of vitamin D levels in relation to OA and vitamin D levels do not affect the relationship of BMD with OA. CONCLUSIONS: Low BMD has a protective role against knee OA while vitamin D deficiency contributes significantly to knee OA severity. However, the association between OA and OP is not affected by vitamin D deficiency and the association of OA and vitamin D serum levels is not affected by BMD.

Atypical vertebral hemangioma: an aggressive form of a benign disease. Case Report and Literature Review.

Vertebral hemangiomas are an incidental and relatively common radiological finding and a benign tumor of vascular origin. VH are the most common spine tumors with an estimated incidence of 1.9-27% in the general population. Rarely, vertebral hemangiomas can exhibit extraosseous expansion with resulting compression of the spinal cord. Such lesions are termed aggressive or atypical vertebral hemangiomas (AVH) and account for less than 1% of spinal hemangiomas. A 68-year-old female was referred with progressive walking difficulty and sensory disturbances in her lower extremities. MRI imaging of the thoracic spine revealed a T1- and T2-weighted hyperintense lesion involving the T10 vertebra. Additionally, there was extraosseous extension of the tumor into the spinal canal, located both anterior and posterior to the spinal cord, causing severe spinal cord compression. A combined endovascular and surgical approach (arterial coil embolization and en bloc resection) for treatment was decided. Although vertebral hemangiomas are an incidental and relatively common radiological finding, the findings of our case were consistent with an aggressive hemangioma with atypical MRI and clinical prognostic characteristics. In summary, the present case highlights the need for multidisciplinary approach and in-depth knowledge of this rare pathologic entity.

Fractures After Removal of Spinal Instrumentation: Revisiting the Stress-Shielding Effect of Instrumentation in Spine Fusion.

BACKGROUND: Many practicing spine surgeons believe that instrumentation can be removed during revision surgery in successful posterolateral or anterior spinal fusions, confirmed by computed tomography and intraoperative exploration. The stress-shielding effect of spinal instrumentation was well described in the late 1980s and 1990s but has not received recent attention. Despite the paucity of recent literature, concepts underlying the biology and biomechanics of the spinal fusion mass remain particularly salient given the increasing incidence of revision spinal fusion surgery. The aim of this study was to highlight a potential complication of instrumentation removal owing to stress shielding of instrumentation on the spinal column and fusion mass. METHODS: A retrospective review was performed, and a small case series was described. RESULTS: In 3 cases, despite apparent solid fusion demonstrated on preoperative computed tomography and confirmed by intraoperative exploration, new fractures developed after removal of instrumentation. In these cases, fracture occurred at the transition zone between the newly rigid instrumented area and previous fusion. This highlights the relative weakness of the fusion and may be explained by the stress-shielding effect of instrumentation within the fusion mass. CONCLUSIONS: Spinal instrumentation revision requires careful consideration, and routine implant removal should not be performed. The presence of a solid fusion on computed tomography and/or at intraoperative exploration may not justify implant removal in these cases. In cases of extension of a fusion, use of a bridging connection to the new implants should be considered. The cases presented demonstrate the consequences of the stress-shielding effect of implants on the spine and fusion mass.

Hypovitaminosis D as a risk factor of subsequent vertebral fractures after kyphoplasty.

BACKGROUND CONTEXT: Over the past 20 years, methods of minimally invasive surgery have been developed for the treatment of vertebral compression fractures. Balloon kyphoplasty and vertebroplasty are associated with a recurrent fracture risk in the adjacent levels after the surgical procedure. In certain patient categories with impaired bone metabolism, the risk of subsequent fractures after kyphoplasty is increased. PURPOSE: To determine the incidence of recurrent fractures after kyphoplasty and explore whether the status of bone metabolism and 25-hydroxyvitamin D (25(OH)D) levels affect the occurrence of these fractures. STUDY DESIGN: Prospective longitudinal clinical study. PATIENT SAMPLE: Forty female postmenopausal women with primary osteoporosis and acute symptomatic vertebral compression fractures. OUTCOME MEASURES: Identification of new vertebral fractures and documentation of indicators of bone metabolism. METHODS: A total of ninety-eight kyphoplasties were performed in 40 female patients. Balloon kyphoplasty was performed on all symptomatic acute vertebral compression fractures. Age, body mass index, history of tobacco use, number of initial vertebral fractures, intradiscal cement leakage, history of nonspinal fractures, use of antiosteoporotic medications, bone mineral density, bone turnover markers, and 25(OH)D levels were assessed. All participants were evaluated clinically and/or radiographically. Follow-up period was 18 months. RESULTS: The mean population age was 70.6 years (range, 40-83 years). After initial kyphoplasty procedure, nine patients (11 levels) (22.5% of patients; 11.2% of levels) developed a postkyphoplasty vertebral compression fracture. Cement leakage was identified in seven patients (17.5%). The patients without recurrent fractures after kyphoplasty demonstrated higher levels of 25(OH)D (22.6±5.51 vs. 14.39±7.47; p=.001) and lower N-terminal cross-linked telopeptide values (17.11±10.20 vs. 12.90±4.05; p=.067) compared with the patients with recurrent fractures. CONCLUSIONS: Bone metabolism and 25(OH)D levels seem to play a role in the occurrence of postkyphoplasty recurrent vertebral compression fractures.

Bone anabolic versus bone anticatabolic treatment of postmenopausal osteoporosis.

Increased bone fragility after menopause is commonly associated with accelerated bone loss and aggressive osteoclastic function. This is attributed to increased RANKL production and impaired osteoprotegerin synthesis. Fast bone loss leads to trabecular perforations, dramatic diminution of bone strength, and unexpected fractures. To avoid osteoporotic fractures, elimination of fast bone loss is recommended. Antiosteoclastic drugs, apart from estrogens, are the selective estrogen receptor modulators, calcitonins, and amino-bisphosphonates. These drugs increase bone mass by 1-5%, but reduce the relative risk of a vertebral fracture by 30-70%. Long-term exposure to bisphosphonates may be related to low bone turnover. In elderly and severe osteoporosis, antiosteoclastic regimens hardly correct the depressed osteoblastic function. Intermittent teriperatide stimulates osteoblastic function, improves bone geometry, and has an additional analgesic effect. While both anticatabolic and anabolic agents increase bone mass and decrease the risk of spinal fractures and occasionally of the fracture of the femoral neck, there are differences in the mode of their action. These pathophysiological differences are tentative therapeutic tools for the prevention of osteoporotic fractures. A fast bone loss, associated with increased biochemical markers, is the main indicator for anticatabolic agents, while impaired bone geometry, normal or low bone markers, and established bone architectural changes are in favor of the anabolic agents. Strontium ranelate combines the anticatabolic effect with an additional anabolic action.