Sciatic Nerve and Its Anatomical Variations: In-Depth Understanding Acquired During Dissection Classes.

Knowledge of anatomical variability is extremely important in order to better understand the etiology of pain, if present, or to avoid iatrogenic consequences. Sometimes the anatomical "anomalies" have the same anamnesis but different causes. For example, sciatic neuralgia may be caused by a herniated disc or it may have a different origin. The sciatic nerve (SN), also known as the ischial nerve, is the widest in the human body. This huge peripheral nerve originates from the roots of the lumbosacral plexus (L4-S3) and passes through the great sciatic foramen, under the piriformis muscle (PM). However, there is much variability in the pattern of SNs about the muscle, which has been known since the first half of the 20th century. In the present study, we describe six different case reports of anatomical variations of the SN and its interplay with the PM. The observations were made during dissection classes at the ICLO Teaching and Research Centre (Verona, Italy), on both male and female cadavers aged between 58 and 84 years. The SN was reported as a single and divided nerve into the tibial nerve (TN) and the common peroneal nerve (CPN), passing alone above, below, or between the PM. However, the two parts of the SN may also interact with the PM in different ways, adding to the anatomical variability. A thorough knowledge of the anatomical variations in any part of the human body is extremely important. The various techniques used, from imaging to autopsy or surgery, are also useful in the SN pathway. Thus, the anatomical features and the understanding of each variation are useful for a correct approach that can lead to an effective and correct treatment with a favorable outcome.

The utility of intraoperative PTH dosage in primary hyperparathyroidism based on preoperative diagnosis and surgical choice.

BACKGROUND: The aim of this study was to evaluate the impact of the intraoperative PTH (ioPTH) monitoring in the success of parathyroidectomy based on the concordant or indeterminate preoperative imaging studies of localization and the performed surgical choices. METHODS: Fourthy-seven patients who received parathyroidectomy operations were divided in four groups: concordance of the imaging and ioPTH, concordance of the imaging and no ioPTH, indeterminate imaging and ioPTH and indeterminate imaging and no ioPTH. RESULTS: Overall, patients in whom ioPTH monitoring was not performed were healed in 89.47% of cases, while the percentage of recovery in patients receiving ioPTH was 85.71%. There were no differences in the changes in strategy or in the cure rates with the use of ioPTH. CONCLUSIONS: No significant differences were found, independently from the preoperative imaging agreement, in either the cure rate or in the change of intraoperative strategy using the ioPTH dosage.