Comprehensive Anatomic and Morphometric Analyses of Triangular Working Zone for Transforaminal Endoscopic Approach in Lumbar Spine: A Fresh Cadaveric Study.

OBJECTIVE: The aim of this study is to provide essential information for endoscopic transforaminal approach by performing morphometric analysis of the triangular working zone (TWZ) in fresh cadavers. METHODS: Fifteen fresh human cadavers (9 women and 6 men) with no history of spinal surgery were used in this study. Anatomic dissection of 150 foraminal levels were performed. Significant surgical landmarks constructing TWZ were measured bilaterally from L1-2 to L5-S1 on 15 fresh cadavers. The relationship between traversing roots and intervertebral discs was defined. RESULTS: Base, height, and hypotenuse measurements of TWZ were longer as the level lowered. Mean base height and hypotenuse of TWZ were 12.15 mm, 11.29 mm, and 16.69 mm (L1-2); 17.94 mm, 17.18 mm, and 28.03 mm (L5-S1), respectively. TWZ was triangular shaped at the upper lumbar levels (L1-2, L2-3, and L3-4), and trapezoid at the lower lumbar levels (L4-5 and L5-S1). Going down the levels, the exiting root angle was narrower, the mean exiting angle of the L5 root being 28.23°. All L2 and L3 traversing roots and nearly all L4 traversing roots (86.7%) originated from below the disc level. Forty percent of L5 traversing roots originated above the disc level, and 53.3% originated at the disc level. Most S1 traversing roots originated at the proximal margin of the disc level (80%). CONCLUSIONS: Our study reveals a detailed morphometric analysis of TWZ. Understanding the foraminal anatomy is crucial for safely performing transforaminal endoscopic surgery. The learning curve of transforaminal surgery can be reduced by garnering knowledge of TWZ anatomy.

Spinal meningiomas: recurrence in ventrally located individuals on long-term follow-up; a review of 46 operated cases.

AIM: Surgical removal of spinal meningiomas is usually not difficult. In neurosurgical practice, their locations and growing patterns may affect surgical results. Ventrally located and en plaque meningiomas may not be removed totally. The aim of this study was to present the results of surgery in cases with spinal meningiomas, and reveal the factors affecting outcome. MATERIAL AND METHODS: There were 46 cases operated between January 1995 and December 2009 in single clinic. There were 33 female and 13 male patients. The mean age was 52. All patients underwent microsurgical resection using posterior approach. RESULTS: Total resection was obtained in 38 patients (82%). Twenty-eight (61%) patients experienced clinical improvement after surgery. The tumor was completely dorsal to the spinal cord in 30 cases, dorsolateral in nine and ventral to the spinal cord in seven cases. We experienced eight recurrences (17%). Recurrences were seen most commonly seen in ventrally located tumors (62%). CONCLUSION: Complete resection of spinal meningiomas seems to produce a good clinical outcome. Recently, advances in microneurosurgery and neuroimaging techniques have resulted in decreases in morbidity and recurrence rates in spinal meningiomas.

Intracranially Retained Sewing Needle in a Child: Does the Rust on the Needle Have any Implication?

A penetrating injury with a sewing needle is a rare phenomenon. The pathophysiological mechanism of late epilepsy after penetrating injuries is not clear. A 10-year-old female child had a seizure. An X-ray study of the skull and the cranial computed tomography scans showed a foreign object retained in the skull cavity. She was intact on neurological examination. Electroencephalogram (EEG) showed that there was bioelectrical disorganization in both hemispheres, being more prominent on the left side. A right posterior frontal median craniotomy was performed in order not to retract the left hemisphere within the interhemispheric fissure and the sewing needle was removed successfully. The sewing needle was rusted. The reason for the patient's seizure, 10 years after the injury, may be the corrosion of the sewing needle and rust formation in this case.