BACKGROUND: This study investigated the lumbosacral plexus (LSP) nerve root thickness and ligamentum flavum (LF) thickness and correlated them with age and sex. These findings provided a useful data for spinal nerve root micro-anastomosis surgery and lumbar decompression surgery.
METHODS: This retrospective study was conducted with 350 individuals with ages ranging from 21 to 80 years under magnetic resonance imaging to evaluate the possible cause of a lower back pain.
RESULTS: According to the morphometric measurements of the LSP root thickness, the diameter gradually increased from L1 to S1. L1 has the thinnest root (3.9 ± 0.81 mm) while S1 has the thickest root (5.45 ± 0.8 mm). The measurements revealed inconsiderable differences in the LSP thickness in relation to age, sex in the study population. Regarding the LF, the thickness of the LF was found to insignificantly increase with age. Besides, the LF thickness was inconsequentially higher in female. The mean thickness of the right LF at different spinal levels was measured (L2-L3 = 3.19 ± 0.27, L3-L4 = 3.38 ± 0.11 mm, L4-L5 = 3.71 ± 0.29 mm, and L5-S1 = 3.64 ± 0.21 mm). The mean thickness of the left LF was non-significantly higher.
CONCLUSIONS: The LSP root and LF thicknesses not related to age or sex.

Nerve transfers are commonly used in treating complete injuries of the brachial plexus, but donor nerves are limited and preferentially directed toward the recovery of elbow flexion and shoulder abduction. The aims of this study were to characterize the anatomical parameters for identifying the nerve to the levator scapulae muscle (LSN) in brachial plexus surgery, to evaluate the feasibility of transferring this branch to the suprascapular nerve (SSN) or lateral pectoral nerve (LPN), and to present the results from a surgical series.
Supra- and infraclavicular exposure of the brachial plexus was performed on 20 fresh human cadavers in order to measure different anatomical parameters for identification of the LSN. Next, an anatomical and histomorphometric evaluation of the feasibility of transferring this branch to the SSN and LPN was made. Lastly, the effectiveness of the LSN-LPN transfer was evaluated among 10 patients by quantifying their arm adduction strength.
The LSN was identified in 95% of the cadaveric specimens. A direct coaptation of the LSN and SSN was possible in 45% of the specimens (n = 9) but not between the LSN and LPN in any of the specimens. Comparison of axonal counts among the three nerves did not show any significant difference. Good results from reinnervation of the major pectoral muscle (Medical Research Council grade ≥ 3) were observed in 70% (n = 7) of the patients who had undergone LSN to LPN transfer.
The LSN is consistently identified through a supraclavicular approach to the brachial plexus, and its transfer to supply the functions of the SSN and LPN is anatomically viable. Good results from an LSN-LPN transfer are observed in most patients, even if long nerve grafts need to be used.

Magnetic resonance imaging fat suppression techniques are commonly used for diagnosis of canine spinal disease, however, studies comparing different techniques are currently lacking. This retrospective, methods comparison study aimed to evaluate water excitation and STIR MRI pulse sequences for visualization of canine lumbar spinal nerve roots. For inclusion, all dogs had to have dorsal planar MRI studies of the lumbar spine using both sequences. Visual grading analysis was used for scoring the following five criteria: degree of fat suppression; nerve root visualization; subjective tissue contrast; presence of noise; and overall better image quality. Scores were independently recorded by three board-certified veterinary radiologists on two separate occasions, 3-6 weeks apart. A total of 90 dogs were sampled. A two-tailed t-test showed that there were significant differences in all scored parameters (P < 0.00001), with the exception of noise (P = 0.47343), and that the water excitation sequence scored higher in all cases excluding noise. A Gwets AC kappa for intraobserver and interobserver reliability showed \"almost perfect\" agreement for the nerve roots in both tests (intra: k = 0.88; inter: k = 0.90). Intraobserver agreement was \"substantial\" for the degree of fat suppression (k = 0.68), subjective tissue contrast (k = 0.75), and overall better image quality (k = 0.76) and it was \"fair\" for the noise (k = 0.46). Interobserver agreement was \"moderate\" for the degree of fat suppression (k = 0.53), subjective tissue contrast (k = 0.63), and overall better image quality (k = 0.66) and \"slight\" for noise (k = 0.25). These findings supported using the water excitation pulse sequence for fat-suppressed MRI of canine lumbar spinal nerve roots.

Intradural nerve anastomosis for bladder innervation has been demonstrated to be useful. However, its clinical application remains limited because of the complex surgery, its complications and extensive bony destruction. The purpose of the current study was to demonstrate the feasibility of extradural spinal root anastomosis for bladder innervation in canines.
Ten beagle dogs were used. The length of the extradural segment of the nerve root, upper nerve root outlet (the point at which it emerges from the spinal dura mater) to S2 (dS2), the S3 (dS3) nerve root outlet distance, and the diameters of the extradural spinal roots were measured. The numbers of nerve fibers from L6 to S3 ventral roots were calculated using immunohistochemical staining.
The extradural spinal roots could be divided into a ventral root (VR) and a dorsal root (DR) before the ganglionic enlargement of the dorsal root, and the extradural motor nerve roots situate ventrally to their corresponding sensory nerve roots. The extradural nerve root lengths of S1 and parts of L7 were longer than the corresponding dS2. The numbers of nerve and motor nerve fibers, and the diameters of extradural nerve roots, were gradually descending from L6 to S3.
The S1 VRs and parts of the L7 VRs can be extradurally anastomosed to the S2 nerves without tension. A nerve graft was needed for extradural anastomosis of L6 VRs and parts of L7 VRs to S2 VRs. This study demonstrated the feasibility of extradural spinal nerve anastomosis for treating neurogenic bladder in canines.