Clinical and radiological results of TLIF surgery with titanium-coated PEEK or uncoated PEEK cages: a prospective single-centre randomised study.

BACKGROUND: A comparison of fusion rates and clinical outcomes of instrumented transforaminal interbody fusion (TLIF) between polyetheretherketone (PEEK) and titanium-coated PEEK (Ti-PEEK) cages is not well documented. METHODS: A single-centre, prospective, randomised study included patients who underwent one-level TLIF between L3-S1 segments. Patients were randomised into one of two groups: TLIF surgery with the PEEK cage and TLIF surgery with the Ti-PEEK cage. Clinical results were measured. All patients were assessed by repeated X-rays and 3D CT scans. Cage integration was assessed using a modified Bridwell classification. The impact of obesity and smoking on fusion quality was also analysed. Patients in both groups were followed up for 2 years. RESULTS: Altogether 87 patients were included in the study: of these 87 patients, 81 (93.1%) completed the 2-year follow-up. A significant improvement in clinical outcome was found in the two measurements scales in both groups (RM: p = 0.257, VAS: p = 0.229). There was an increase in CobbS and CobbL angle in both groups (p = 0.172 for CobbS and p = 0.403for CobbL). Bony fusion was achieved in 37 of 40 (92.5%) patients in the TiPEEK group and 35 of 41 (85.4%) in the PEEK group (p = 0.157). Cage subsided in 2 of 40 patients (5%) in the TiPEEK group and 11 of 41 (26.8%) in the PEEK group (p = 0.007). Body mass index > 30 and smoking were not predictive factors of bony fusion achievement. CONCLUSION: There is no significant advantage of TiPEEK cages over PEEK cages in clinical outcome and fusion rate 2 years after surgery.

Intramedullary ependymoma: long-term outcome after surgery.

BACKGROUND: Overall (OS) and progression-free survival (PFS) of patients undergoing spinal ependymoma resection has been frequently reported. Contrarily, OS and PFS of purely intramedullary ependymomas have not been clearly determined yet. METHODS: The data of 37 patients undergoing resection of an intramedullary ependymoma (IE) from January 2000 to December 2016 were analysed retrospectively. RESULTS: The mean age was 46 years. The male:female ratio was 24:13. The median duration of symptoms was 12 months. Sixty-two per cent of ependymomas were in the cervical, 24% in the thoracic, and 14% in the conus region in our series. The median volume was 1.3 ml. A syrinx was found in 49% and a cyst in 32%. GTR was achieved in 89%, STR in three (8%), and PR in one patient (3%). Median follow-up was 114 months. PFS was 87%, 82%, and 82% at 5, 10, and 15 years, respectively. OS was 97%, 88%, and 63% at 5, 10, and 15 years, respectively. There was a significant difference in PFS depending on the extent of resection and in OS depending on the pre-operative clinical status. There was no significant difference in OS and PFS regarding the other examined influencing factors. CONCLUSION: GTR resection was the most important factor influencing PFS. According to our results OS of IEs is much worse than that of spinal ependymomas. Our analysis confirms that patients with good pre-operative (McCormick grade 1 and 2) clinical status have significantly better OS than patients with McCormick grade 3 and higher.

Epidural hematoma - benign or potentially malignant disease?

INTRODUCTION: Epidural hematoma (EDH) is generally considered to be a condition with a good prognosis. However, postoperative results of numerous studies have shown that mortality and morbidity remain relatively high. The aim of our article is to evaluate surgical outcomes in patients undergoing EDH evacuation over the last five years. METHODS: Data were analysed retrospectively. Pre-operative GCS was assessed. Location and incidence of associated head injuries were recorded. Two groups were established: 1. "immediate-care-requiring" and "followed-up" patients. Time interval CT - surgery was measured in the first group and the number of CT scans in the second group. Complications were divided into general and surgical. Outcome was evaluated on GOS. RESULTS: 67 patients underwent the surgery. At admittance, GCS was 13-15 in 55%, 9-12 in 8% and 3-8 in 37% of the patients. EDH was mostly located in the temporal region - in 52%. Associated head injuries occurred in 76%. Mean interval CT - operation lasted 2h 15min in the first group. Two pre-operative CT scans were done in 88% of the patients in the second group. General complications occurred in 34% and surgical in 15%. Mortality rate was 6%. 20% of the patients had a GOS of 1-3 and 80% of them had a GOS of 4-5. CONCLUSION: Our results have shown that morbidity and mortality after EDH evacuation are still relatively high. 14% of the patients remained disabled, and 6% died. The outcome depends mostly on preoperative clinical picture and timing of the surgery. Key words: epidural hematoma - evacuation - neurological outcome - timing of the surgery.

Variable intraspecific space use supports optimality in an apex predator.

Within optimality theory, an animal's home range can be considered a fitness-driven attempt to obtain resources for survival and reproduction while minimizing costs. We assessed whether brown bears (Ursus arctos) in two island populations maximized resource patches within home ranges (Resource Dispersion Hypothesis [RDH]) or occupied only areas necessary to meet their biological requirements (Temporal Resource Variability Hypothesis [TRVH]) at annual and seasonal scales. We further examined how intrinsic factors (age, reproductive status) affected optimal choices. We found dynamic patterns of space use between populations, with support for RDH and TRVH at both scales. The RDH was likely supported seasonally as a result of bears maximizing space use to obtain a mix of nutritional resources for weight gain. Annually, support for RDH likely reflected changing abundances and distributions of foods within different timber stand classes. TRVH was supported at both scales, with bears minimizing space use when food resources were temporally concentrated. Range sizes and optimal strategies varied among sex and reproductive classes, with males occupying larger ranges, supporting mate seeking behavior and increased metabolic demands of larger body sizes. This work emphasizes the importance of scale when examining animal movement ecology, as optimal behavioral decisions are scale dependent.