Incidence of surgical site infections after cervical spine surgery: results of a single-center cohort study adhering to multimodal preventive wound control protocol.

PURPOSE: The incidence of surgical site infections is considered a relevant indicator of perioperative and postoperative care quality. The aim of this study is to analyze and evaluate SSIs after elective cervical spine surgery under the guidance of our preventive multimodal wound protocol. METHODS: A monocentric observational cohort study analyzed 797 patients who underwent cervical spine surgery from 2005 to 2010 (mean age 51.58 ± 11.74 year, male 56.09%, mean BMI 26.87 ± 4.41, ASA score 1-2 in 81.68% of patients), fulfilling the entry criteria: (1) cervical spine surgery performed by neurosurgeons (degenerative disease 85.19%, trauma 11.04%, tumor 3.76%), (2) elective surgery, (3) postoperative care in our neurointensive care unit. Our preventive wound control protocol management focused mainly on antibiotic prophylaxis, wound hygiene regime, and drainage equipment. All wound complications and surgical site infections were monitored up for 1 year after surgery. RESULTS: We had only 2 (0.25%) patients with SSI after cervical spine surgery-one organ/space infection (osteomyelitis, primary due to liquorrhea) after anterior surgical approach, and one deep surgical site infection (due to dehiscence) after posterior approach. We had 17 (2.13%) patients with some wound complications (secretion 7, dehiscence 4, hematoma 1, edema 3, and liquorrhea 2) that were not classified as SSI according to the CDC guidelines. CONCLUSION: Concerning our study population of patients undergoing elective cervical surgery, with ASA scores 1-2 in 81.68% of our patients, the incidence of SSI was 0.14% after anterior surgical approach, 1.4% after posterior surgical approach, and 0.25% altogether in the referred cohort.

Biomechanics optimisation of the laminoplasty groove size and position: A numerical study.

BACKGROUND: This study is focused on the opening technique of the cervical vertebrae during laminoplasty which serves to substantially reduce the most severe adverse effects of the simple resection of posterior vertebral elements. This computational study aims to clarify by an optimisation approach what shape and position upon the lamina the groove should have. METHODS: The computational model was developed in the computational software COMSOL Multiphysics 5.6a based on a computer tomography data obtained from the C4 vertebra. For finding the optimal minimum or maximum of a function (surface), optimisation algorithms are developed following the Nelder-Mead algorithm. RESULTS: The reaction-opening force increases with a decreasing groove radius and an increasing position from the vertebra body. The created area increases with a decreasing groove radius and a decreasing position. As the opening happens mostly only above the groove, the opening area increases only in this location. Moreover, the von Mises stress peak value is almost twice as large as in the case of maximization of the opening area, which might result in breaking of the lamina as the thickness of the lamina would be reduced to its minimum. CONCLUSION: The groove radius and position can affect the opening force and the opening area in case of double door laminoplasty. The opening force is highly influenced by the groove position and radius. The best position for placing the groove is in the middle of the lamina and the radius of the groove should be as large as possible.

Individualized perioperative management in transoral spine surgery: a single-center cohort study evaluating surgical wound complications and wound infections.

BACKGROUND: Transoral spine surgery is specific due to both its surgical approach and the spectrum of diseases it targets. Patients with high age and elevated clinical frailty scores are often involved, and there are reports of increased risks of surgical site infection (SSI) due to extended exposures requiring maxilotomy or mandibulotomy. Our case series describes surgical wound complications under the meticulous application of individualized perioperative multimodal management. METHODS: Our primary outcome was the occurrence of SSI and the secondary outcome was the occurrence of other noninfectious wound complications evaluated in 22 adult patients who consecutively underwent the transoral spine surgery from 2001 to 2018 (trauma - C2, cervical nonunion: 6 patients, 27%; tumor: 4 patients, 18%; osteomyelitis: 6 patients, 27%; other non-traumatic cases: 6 patients, 27%). Structuralized data comprising parameters related to nosocomial infections after spine surgery were continuously processed and put into specialized database of preventive multimodal nosocomial infection control protocol that was used as a main source of analyzed parameters. The mean age of studied cohort was 54.9 [Formula: see text] 15.5 years, with 68% males, mean body mass index (BMI) 24.9 [Formula: see text] 5.22, and the mean clinical frailty score was 2.59 [Formula: see text] 1.07. There were 7 patients (32%) who only had the transoral approach and 15 patients (68%) having this approach followed by additional posterior approach. We observed SSI from all wound complications for up to one year after surgery. RESULTS: There were 4 (18%) superficial wound complications from transoral approach, but none of them were infected. We had 2 patients (13%) with deep wound infections after subsequent posterior approach, but only one (4.5%) was classified as SSI. CONCLUSIONS: We describe the wound complications and the incidence of SSI in a series of 22 patients after the transoral surgery. Considering the average values of the clinical frailty score reaching 2.59, American Society of Anesthesiologists score of 2.73, and the BMI of 26.87, the transoral spine surgery did not seem to be a considerable risk for SSI in the analyzed cohort, provided preventive perioperative multimodal management is properly individualized and followed.

The opening size of the laminoplasty is dependent on the groove size: A numerical study.

BACKGROUND: The expansion of the cervical vertebrae lamina appears to be crucial to related surgical procedures. The dimensions of the groove influence the strain concentration within the lamina of the vertebra and, thus, the potential success or failure of respective surgical procedure. The aim of this computational study is to clarify both the role of the size of the groove with concern to both the open door and the double door laminoplasty techniques. METHODS: Finite element models were created via computer tomography with varying lamina groove dimensions. Displacements were applied to the models at the open side of the vertebral arch and the vertebral body was constrained prior to movement along all the axes. The maximal opening size measured on the inner side of the lamina and the percentage increase in the initial spinal areas were subsequently analyzed. FINDINGS: The elastic strain concentration value was observed for the groove in all cases, while the maximal principal elastic strain concentration value was observed at the opposite side to the groove cut into the lamina, also in all cases. The maximal area increase related to the 4 mm groove accompanied by the preservation of the ventral cortex of the bone. INTERPRETATION: The study suggested three conclusions a) the wider the groove, the greater is the opening potential, b) the maximal opening size following laminoplasty is not dependent on the depth of the bone cut for this type of groove, c) no benefit accrues in terms of the opening size following the cutting of a supplementary groove at the beginning of the lamina.

Risk factors associated with surgical site infections after thoracic or lumbar surgery: a 6-year single centre prospective cohort study.

BACKGROUND: Surgical site infection (SSI) is a risk in every operation. Infections negatively impact patient morbidity and mortality and increase financial demands. The aim of this study was to analyse SSI and its risk factors in patients after thoracic or lumbar spine surgery. METHODS: A six-year single-centre prospective observational cohort study monitored the incidence of SSI in 274 patients who received planned thoracic or lumbar spinal surgery for degenerative disease, trauma, or tumour. They were monitored for up to 30 days postoperatively and again after 1 year. All patients received short antibiotic prophylaxis and stayed in the eight-bed neurointensive care unit (NICU) during the immediate postoperative period. Risk factors for SSI were sought using multivariate logistic regression analysis. RESULTS: We recorded 22 incidences of SSI (8.03%; superficial 5.84%, deep 1.82%, and organ 0.36%). Comparing patients with and without SSI, there were no differences in age (p=0.374), gender (p=0.545), body mass index (p=0.878), spine diagnosis (p=0.745), number of vertebrae (p=0.786), spine localization (p=0.808), implant use (p=0.428), American Society of Anesthesiologists (ASA) Score (p=0.752), urine catheterization (p=0.423), drainage (p=0.498), corticosteroid use (p=0.409), transfusion (p=0.262), ulcer prophylaxis (p=0.409) and diabetes mellitus (p=0.811). The SSI group had longer NICU stays (p=0.043) and more non-infectious hospital wound complications (p<0.001). SSI risk factors according to our multivariate logistic regression analysis were hospital wound complications (OR 20.40, 95% CI 7.32-56.85, p<0.001) and warm season (OR 2.92, 95% CI 1.03-8.27, p=0.044). CONCLUSIONS: Contrary to the prevailing literature, our study did not identify corticosteroids, diabetes mellitus, or transfusions as risk factors for the development of SSI. Only wound complications and warm seasons were significantly associated with SSI development according to our multivariate regression analysis.

N-terminal pro-B-type Natriuretic Peptide in three different mechanisms of dysnatremia onset after a child's craniopharyngioma surgery.

Craniopharyngioma, due to its sellar location, can be perioperatively complicated by different types of dysnatremia. We present a rare postoperative onset of a combination of three different mechanisms of dysnatremia with N-terminal pro-B-type Natriuretic Peptide (NT-proBNP) and renal function parameters in a boy with a good outcome after craniopharyngioma surgery: 1/ Central diabetes insipidus (CDI) onset immediately after the operation, hypernatremia with peak serum sodium (SNa) 158 mmol/l) caused by free water polyuria (electrolyte-free water clearance, EWC 0.104 ml/s), NT-proBNP 350 pg/ml; 2/ cerebral salt wasting (CSW) onset on day 7, hyponatremia (SNa 128 mmol/l) with hypoosmolality (measured serum osmolality, SOsm 265 mmol/kg) caused by natriuresis (sodium - daily output 605 mmol/day, fractional excretion 0.035), NT-proBNP 191 pg/ml; 3/ Polydypsia onset on day 11 caused hyponatremia (SNa 132 mmol/l), EWC 0.015, NT-proBNP 68 pg/ml.

Heterotopic ossification in total cervical artificial disc replacement.

STUDY DESIGN: Prospective clinical study enrolled in 2 centers (Munich and Liberec) as part of a prospective European multicenter study with ProDisc C (Synthes Inc., Paoli, PA). OBJECTIVES: The first goal of the study was to evaluate the rate of heterotopic ossifications identified with plain radiograph following total cervical disc replacement (TCDR). The second goal was to show whether segmental motion can be preserved, and whether TCDR can provide improvement of the patient's ability to perform activities of daily living as well as a decrease of pain. SUMMARY OF BACKGROUND DATA: Only a few reports about the radiologic outcome after TCDR are published so far. Heterotopic ossification is a well-known phenomenon after total hip arthroplasty. The rate of heterotopic ossification following TCDR is unclear. METHODS: The radiographs of 54 patients (in total, 77 implanted prostheses) were analyzed 1 year after TCDR with a ProDisc C prosthesis. We classified the heterotopic ossification in 5 grades according to a recently published classification system for lumbar total disc replacement. For clinical parameters, the visual analog scale and the Neck Disability Index were evaluated preoperatively and 1 year postoperatively. The Student t test and Wilcoxon test were used for statistical analysis. RESULTS: In 26 treated segments (33.8%), no heterotopic ossification was detectable. Grade 1 ossifications were present in 6 levels (7.8%). A total of 30 segments (39.0%) showed grade 2 ossifications. Heterotopic ossifications that led to restrictions of the range of motion were present in 8 cases (10.4%). One year postoperatively, 7 cases (9.1%) had a spontaneous fusion of the treated segment. The clinical parameters improved significantly and were similar to previous reports about TCDR. CONCLUSIONS: Only 33.8% of the patients did not show any signs of heterotopic ossification, and the rate of spontaneous fusion after TCDR 1 year after surgery was unexpectedly high. There were 49.4% of the patients with grade 2-3 ossification, which lets us suspect an even higher rate of spontaneous fusion after long-term follow-ups. Motion preservation after TCDR is only guaranteed if spontaneous fusion can be prevented. Thus, mobility of the implanted segments needs to be further studied.