Trigeminal nucleus caudalis anatomy: guidance for radiofrequency dorsal root entry zone lesioning.

OBJECT: This study seeks to improve the accuracy of trigeminal nucleus caudalis dorsal root entry zone (DREZ) radiofrequency lesioning by quantifying the size and orientation of the nucleus caudalis. METHODS: Using serial axial photographs of 6 formalin-fixed cadaver brainstems, digital nucleus caudalis measurements were taken at 1-mm intervals from the level of the obex to the C(2) dorsal nerve roots. RESULTS: From the obex to the C(2) dorsal nerve roots, the nucleus caudalis decreases in width (from 2.6 ± 0.2 to 1.0 ± 0.3 mm) and, excluding superficial tract thickness, decreases in axial nucleus depth (from 2.4 ± 0.3 to 1.7 ± 0.2 mm). At levels between the obex and 10 mm caudal to the obex, the accessory nerve rootlets exit the brainstem at the junction of the spinal trigeminal tract and the dorsal spinocerebellar tract. CONCLUSION: This study details the anatomic dimensions and orientation of the nucleus caudalis for surgeons who perform DREZ lesioning.

Determining the relationship of the axillary nerve to the shoulder joint capsule from an arthroscopic perspective.

BACKGROUND: The axillary nerve is out of the field of view during shoulder arthroscopy, but certain procedures require manipulation of capsular tissue that can threaten the function or integrity of the nerve. We studied fresh cadavers to identify the course of the axillary nerve in relation to the glenoid rim from an intra-articular perspective and to determine how close the nerve travels in relation to the glenoid rim and the inferior glenohumeral ligament. METHODS: We dissected nine whole-body fresh-tissue shoulder joints and exposed the axillary nerve through a window in the inferior glenohumeral ligament. Then we cut coronal sections through the glenoid fossa of ten unembalmed, frozen shoulder specimens after the axillary nerve had been stained with Evans blue dye. All specimens were studied with the joint secured in the lateral decubitus position used for shoulder arthroscopy. RESULTS: Microsurgical dissection through the inferior glenohumeral ligament from within the joint capsule revealed the axillary nerve as it traversed the quadrangular space. In each dissection, the teres minor branch was the closest to the glenoid rim. The coronal sectioning of the unembalmed shoulder specimens demonstrated that the closest point between the axillary nerve and the glenoid rim was at the 6 o'clock position on the inferior glenoid rim. At this position, the average distance between the axillary nerve and the glenoid rim was 12.4 mm. The axillary nerve lay, throughout its course, at an average of 2.5 mm from the inferior glenohumeral ligament. CONCLUSIONS: We used two novel approaches to map the axillary nerve from an intra-articular perspective. Our analysis of the position of the nerve with use of these methods provides the shoulder arthroscopist with essential information regarding the location, route, and morphology of the nerve as it passes inferior to the glenoid rim and shoulder capsule.

A case of bilateral ectopic superior cervical ganglia in man.

Bilateral ganglionic masses, likely representing fused superior and middle cervical sympathetic ganglia, were found in the mid-neck region of a cadaver during routine dissection. The displacement of the superior cervical ganglion from its normal location is a striking anomaly that does not appear to have been reported earlier. This observation may be clinically relevant for avoiding misdiagnosis of such masses as Schwannomas or other tumors. In addition, in cases where the superior cervical ganglion is absent from its usual location, it should be sought in the mid-neck region.

Female genital anomalies affecting reproduction.

OBJECTIVE: A multitude of female congenital anomalies are uncommon. However, their impact on reproduction can be profound. The aim of this review is to remind the practicing physician of the clinically relevant embryology and summarize the studies that look at the impact of such various anomalies on a woman's fecundity. We review particular surgical therapies that possibly may improve fertility in such women. DESIGN: Review and critique of available studies in which particular surgical therapies were done and whether they truly improved fertility in these women with congenital reproductive anomalies. RESULTS: Clear evidence demonstrates that uterine septum resection is effective in women with demonstrated recurrent pregnancy losses. Arcuate uterus has little impact on reproduction. Other studies fail to definitively show that surgical correction will improve pregnancy retention or fertility except for specifically indicated clinical scenarios. CONCLUSIONS: The practicing reproductive specialist should have working knowledge of evidence-based therapeutic options for women with reproductive congenital anomalies. A summary chart has been devised to clearly associate embryologic structures with normal adult derivative as well as anomalous structures.