No abstract

This study was to develop a feasible and safe animal model for minimally invasive injectable lumbar interbody fusion using a novel biomaterial, mineralized collagen-polymethylmethacrylate bone cement (MC-PMMA), with unilateral pedicle screw fixation in an in vivo goat model. Eight goats ( Capra aegagrus hircus) were divided into three groups: MC-PMMA, unmodified commercial-polymethylmethacrylate bone cement (UC-PMMA), and a control group (titanium cage filled with autogenous bone, TC-AB). Each group of goats was treated with minimally invasive lumbar interbody fusion at the L3/L4 and L5/L6 disc spaces (injected for MC-PMMA and UC-PMMA, implanted for TC-AB). The pedicle screws were inserted at the L3, L4, L5, and L6 vertebrae, respectively, and fixed on the left side. The characteristics of osteogenesis and bone growth were assessed at the third and the sixth month, respectively. The methods of evaluation included the survival of each animal, X-ray imaging, and 256-layer spiral computed tomography (256-CT) scanning, imaged with three-dimensional microfocus computed tomography (micro-CT), and histological analysis. The results showed that PMMA bone cement can be extruded smoothly after doping MC, the MC-PMMA integrates better with bone than the UC-PMMA, and all goats recovered after surgery without nerve damage. After 3 and 6 months, the implants were stable. New trabecular bone was observed in the TC-AB group. In the UC-PMMA group a thick fibrous capsule had formed around the implants. The MC-PMMA was observed to have perfect osteogenesis and bone ingrowth to adjacent bone surface. Minimally invasive injectable lumbar interbody fusion using MC-PMMA bone cement was shown to have profound clinical value, and the MC-PMMA showed potential application prospects.

The aim of this study was to investigate the occurrence and patterns of the communicating branches of cords of the brachial plexus (BPs). This study was performed with 50 fixed adult cadavers (all 100 sides). The BPs were exposed, the presence of the communicating branches of BPs were determined, measured, and photographed. The communicating branches were identified in 27 sides of the BPs. According to enthesis, the communicating branches between the medial and lateral cords (25 sides) were divided into five types. The most common branches connected the lateral cord with the medial root of the median nerve (16 sides). All the communicating branches between the lateral and medial cords obliquely crossed anterior to the axillary artery and passed below the thoracoacromial artery trunk. The distance of the communicating branch with the origin of thoracoacromial artery trunk was 1.60 ± 0.64 cm. The length, transverse diameter, and anteroposterior diameter of communicating branch were 1.67 ± 0.62 cm, 1.77 ± 0.63 mm, and 1.91 ± 0.34 mm, respectively. These anatomical data about the communicating branches will be helpful for surgeons who perform surgical procedures in the cervical and axillary regions.

The aim of this study was to provide a detailed characterization of the rami communicantes between the stellate (or cervicothoraic) ganglion (CTG) and brachial plexus (BP). Rami communicantes of 33 fixed adult cadavers were macroscopically observed, and connection between CTG and spinal nerves and branching was investigated. In all cases, except one, the hibateral medial rami communicantes was found to be positioned symmetrically between the CTG and C7, C8 spinal nerves. Gray rami communicantes arising from the CTG joined C8, C7, C6 nerve roots on 66, 63, and 6 sides, respectively, and branched from the rami communicantes to C7, C6, C5 nerve roots lying on 51, 41, and 2 sides, respectively. Forty-five sides of the branches from rami communicantes derived from CTG to C8 were observed to ascend through the transverse foramina of the C7 nerve. The branches from rami communicantes derived from CTG to C7 to the C6 nerve were observed ascending through the foramen transversarium of the six cervical vertebrae along with the vertebral artery and joining the C6 spinal nerve in 41 sides. Knowledge about the general distribution and individual variations of the rami communicantes between CTG and BP will be useful toward studies involving the inference of sympathetic nerve stimulation of the upper limbs and could be important for surgeons who perform surgical procedures in the cervical region or medical blockade of nerve fibers.