Gel Based on Hydroxyethyl Starch with Immobilized Amikacin for Coating of Bone Matrices in Experimental Osteomyelitis Treatment.

A polysaccharide gel containing covalently bound amikacin, a broad-spectrum antibiotic, was produced by using epichlorohydrin-activated hydroxyethyl starch (HES). The structure of the polymers was analyzed by 13C and 1H nuclear magnetic resonance (13C NMR and 1H NMR) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The sites of covalent attachment of amikacin to the epoxypropyl substituent and the HES backbone were determined. The antibacterial activity of the polymer was evaluated in vitro using the agar well diffusion method with the Staphylococcus aureus P209 strain. It was demonstrated that the polymer retained activity in the presence of bacterial amylase, which is released upon bacterial attack. The gel was applied for coating pores and surfaces of a biocomposite material based on a xenogenic bovine bone matrix. In vivo experiments showed the effectiveness of utilizing amikacin-containing biocomposite bone-substitute materials in the treatment of experimental osteomyelitis in rats using objective histological control and X-ray tomography.

Transoral Decompression and Stabilization of the Upper Cervical Segments of the Spine Using Custom-Made Implants in Various Pathologic Conditions of the Craniovertebral Junction.

BACKGROUND: Surgical treatment of patients with atlantoaxial instability caused by pathologic changes of the skull base and craniovertebral junction combined with anterior compression of the brain stem is still associated with substantial technical difficulties and remains a matter of debate. Currently, anterior stabilization of the atlantoaxial junction is a promising approach that allows for the resection of the pathologic lesion of the skull base and craniovertebral junction with subsequent stabilization of C1-C2 or C1-C3 in 1 stage. METHODS: In this article, we present 5 clinical cases in which transoral decompression and anterior stabilization of the C1-C2 (4 cases) and C1-C3 (1 case of anteroposterior stabilization) segments with custom-made fixation systems was used to treat various pathologic conditions of the craniovertebral junction. RESULTS: In all cases, complete removal of the pathologic lesion and decompression of the upper cervical spinal cord as well as reliable stabilization of the upper spinal segments were achieved. Some degree of movement in the cervical spine was preserved in all patients due to unfixed C0-C1 and C3-C7 segments in 4 cases and C0-C1 and C4-C7 in 1 case. Implant migration or instability was not observed in any of the cases. The follow-up period was from 1 to 4 years after surgery. CONCLUSIONS: The first experience of anterior fixation using individually manufactured C1-C2 and C1-C3 systems demonstrated their effectiveness. This approach can be safely used as an alternative or in combination with standard posterior stabilization methods. An innovative surgical technology developed and implemented in our surgical practice allows for optimization of the surgical technique, reduces the number of perioperative complications, eliminates movement restrictions in the cervical spine, improves motor activity, and makes earlier patient rehabilitation possible.

Transoral Decompression and Anterior Stabilization of Atlantoaxial Joint in Patients with Basilar Impression and Chiari Malformation Type I: A Technical Report of 2 Clinical Cases.

OBJECTIVE: Presentation of clinical cases involving successful anterior stabilization of the C1-C2 segment in patients with invaginated C2 odontoid process and Chiari malformation type I. METHODS: Clinical case description. RESULTS: Two patients with C2 odontoid processes invagination and Chiari malformation type I were surgically treated using the transoral approach. In both cases, anterior decompression of the upper cervical region was performed, followed by anterior stabilization of the C1-C2 segment. In 1 of the cases, this procedure was performed after posterior decompression, which led to transient regression of neurologic symptoms. In both cases, custom-made cervical plates were used for anterior stabilization of the C1-C2 segment. During the follow-up period of more than 2 years, a persistent regression of both the neurologic symptoms and Chiari malformation was observed. CONCLUSIONS: Anterior decompression followed by anterior stabilization of the C1-C2 segment is a novel and promising approach to treating Chiari malformation type I in association with C2 odontoid process invagination.