OBJECTIVERecent studies have described encouraging outcomes after cervical total disc replacement (cTDR), but there are also critical debates regarding the long-term effects of heterotopic ossification (HO) and the prevalence of adjacent-level degeneration. The aim in this paper was to provide 4-year clinical and radiographic outcome results on the activ C disc prosthesis.METHODSA total of 200 subjects underwent single-level activ C (Aesculap AG) implantation between C-3 and C-7 for the treatment of symptomatic degenerative disc disease. Clinical and radiographic assessments were performed preoperatively, intraoperatively, at discharge, and again at 6 weeks, 6 months, 1 year, 2 years, and 4 years. Radiographic evaluations were done by an independent core laboratory using a specific software for quantitative motion analysis.RESULTSNeck Disability Index (NDI) and visual analog scale (VAS) score for neck and arm pain decreased significantly from baseline to the 4-year follow-up. The mean improvement for NDI was 20, for VAS severity and frequency of neck pain 26.4 and 28, and for VAS severity and frequency of arm pain 30.7 and 35.1, respectively. The neurological situation improved for the majority of patients (86.4%); 76.1% of cases were asymptomatic. Subsequent surgical interventions were reported in 7% of the cases, including device removals in 3%. In 2.5% a subsidence greater than 3 mm was recorded; 1 of these cases also had a migration greater than 3 mm. No device displacement, expulsion, disassembly, loose or fractured device, osteolysis, or facet joint degeneration at the index level was observed. Segmental lordotic alignment changed from −2.4° preoperatively to −6.2° at 4 years, and postoperative height was maintained during the follow-up. Advanced HO (Grade III and IV) was present in 27.1% of the cases; 82.4% showed segmental mobility. A progression of radiographic adjacent-segment degeneration occurred in 28.2%, but only 4.5% required surgical treatment.CONCLUSIONSThe activ C is a safe and effective device for cervical disc replacement confirming the encouraging results after cTDR.Clinical trial registration no.: NCT02492724 (clinicaltrials.gov)
I-125 seeds were permanently implanted into 25 parasellar-clival meningiomas (median age of patients, 56 y) and 19 globoid meningiomas in the elderly (median age of patients, 77 y) using stereotactic technique and 3-D dose planning. Total dose at the tumour margin was increased during the series from 100 Gy to 150 Gy. The procedure caused no mortality and no serious bleeding, but injury to the III cranial nerve due to puncture occurred in one (4%) of the 25 parasellar-clival meningiomas. In two (4.5%) of the 44 cases the postoperative CT scan showed a misplaced seed, located at the tumour surface. Nonenhancing hypodense rings developed around the seeds ('hot spots') with a median diameter of 10.5 mm at 12 months corresponding to a median initial activity of 8.7 mCi. In general, meningiomas responded by slow reduction in volume. The parasellar-clival meningiomas were followed-up for a median of 19 months (6-32), and so far 4 tumours have shrunk moderately, 13 slightly, and 5 not at all. Pre-operative III, V or VI cranial nerve signs were present in 17 patients and subsided in 8 of them. On the other hand, facial numbness developed or increased in 9 of the 25 patients, indicating that the V nerve is rather sensitive to this type of irradiation. In the 19 meningiomas of the elderly, the median follow-up time was 14 months (5-26). The median relative tumour volume was 46% at 12 months. Accounting for tumour-related deaths only, the actuarial survival rate was 78% at 12 months and 62% at 24 months. In general, brain oedema persisted despite reduction in tumour volume. Stereotactic implantation of I-125 seeds into intracranial meningiomas is relatively safe. Interstitial radiotherapy represents a potential tool in the control of medium-sized intracranial meningiomas with minimal brain oedema, but its long-term impact and untoward effects remain to be followed-up.
Fifteen percent of patients underwent a re-operation during the follow-up. The outcome for re-operated patients is similar to patients without a re-operation. A multilevel fusion does not predispose to adjacent level degeneration. A solid fusion can be achieved without plating.
Our results confirm the influence of CORi location on segmental alignment, kinematics and HO for a semi-constrained CTDR, but it also indicates a multifactorial process.
Qualitative and quantitative variation of some terpene compounds in pine needles was determined using static headspace gas chromatography (HSGC) in order to obtain information about the inheritance and gene control of Scots pine (Pinus sylvestris L.) terpenes. Needles of more than 600 trees or seedlings belonging to a control-pollinated and its open-pollinated progeny were analysed. The terpenes were identified by headspace gas chromatographic-mass spectrometric techniques. The terpene patterns obtained by HSGC for the needle volatile fraction and by GC for the hydrodistilled needle volatile oil did not differ much. The hybrids obtained in the control-pollinated crosses were either the high or low 3-carene chemotype. Their open-pollinated seedlings were also of these two chemotypes. The quantitative variation in the terpene concentrations permitted construction of a frequency distribution diagram for each terpene compound. The evidence from the bimodal distribution indicates that the relative amounts of monoterpenes 0-pinene, sabinene, 3-careneI myrcene and terpinolene in Pinus sylvestris L. are simply inherited, i.e. controlled by a single gene with major gene effects. The rest of the monoterpenes and all the sesquiterpenes were normally distributed and their inheritance thus seems to be of a polygenic nature.
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