最后一句Nonetheless转折？

Other benefits of neuraxial anesthesia for spine surgery include a surprisingly low incidence of dural-leak-related headache. Despite concerns regarding post-dural puncture headache (PDPH) related to spinal anesthesia, the incidence of this complication is very low when patients receive spinal anesthesia for spine surgery. In fact, some studies find spinal anesthesia results in a lower incidence of dural-leak headache compared to general anesthesia for spine surgery. The reason for this counterintuitive finding is thought to be related to better operating conditions seen with spinal and neuraxial anesthesia, leading to a decreased risk of surgical dural tear during the operation. Moreover, some authors suggest that surgical bleeding in area of dural puncture functions as “mini blood patch” [5] to prevent any PDPH related to neuraxial techniques. Nonetheless, some studies report significantly lower rates of headache following spinal anesthesia for spine surgery, compared to general anesthesia [5].

椎管内麻醉对脊柱手术的其他益处包括与硬脊膜渗漏相关头痛的发生率低得惊人。尽管担心与脊麻相关的硬膜穿刺后头痛 (post-dural puncture headache，PDPH)，但当患者在脊麻下行脊柱手术时，这种并发症的发生率非常低。事实上，某些研究发现，与全身麻醉的脊柱手术相比，脊麻导致硬脊膜渗漏性头痛的发生率较低。这一违反直觉发现的原因，认为与脊髓和椎管内麻醉呈现更好的手术条件有关，因此导致手术中硬脊膜撕裂的风险降低。此外，一些作者提出硬脑膜穿刺区域的手术出血起到“微型血补片”的作用^[5]，以避免任何与椎管内技术相关的PDPH。尽管如此，一些研究报告称，与全身麻醉相比，脊柱手术脊麻后头痛的发生率显著降低^[5]。

老师，前后都在说与全麻相比，脊麻后头痛的发生率低，那为啥最后一句Nonetheless转折一下，不是应该顺承关系吗？

是不是Nonetheless与前面的In fact并列，都属于转折，都是对Despite这句话转折