tailieunhanh - Spinal Disorders: Fundamentals of Diagnosis and Treatment Part 103

Spinal Disorders: Fundamentals of Diagnosis and Treatment Part 103. Spinal disorders are among the most common medical conditions with significant impact on health related quality of life, use of health care resources and socio-economic costs. Spinal surgery is still one of the fastest growing areas in clinical medicine. | Infections of the Spine Chapter 36 1023 Figure 1. Pathomechanism of spinal infections a The richly vascularized vertebral bodies with their valveless venous plexus Batson predispose to infection in this anatomic region. b Hematogenous seeding from peripheral ulcers genitourinary infection or pulmonary infection can result in an outbreak of the infection close to the vertebral endplates and affect the intervertebral disc. Pathogenesis Spinal infections are assumed to start from the disc space in children in whom the intervertebral disc is still vascularized. In contrast the disease appears to start from the vertebral endplates in adults. However this strict distinction has recently been questioned by Ring et al. 41 who consider it more a continuous disease. The blood supply to the vertebral bodies and intervertebral disc remains a key issue in the predilection of spinal infections. The most frequent pathomechanism is a hematogenous spread of microorganisms via the blood vessels resulting from urogenital pulmonary or diabetic foot infections Fig. 1 . Batson 2 assumed that the valveless venous plexus and the slow blood flow within predisposes to spinal infections of the vertebral body. Wiley and Trueta 50 have provided evidence from injection studies that the arterial route is of significant relevance. Today it is assumed that both mechanisms play a role. With the increased frequency of spinal interventions direct inoculation of microorganisms has become an additional relevant pathomechanism 3 4 10 . The richly vascularized vertebral bodies predispose to spinal infections Classification Spinal infections can be classified according to the causative organism. Classically we differentiated between specific and so-called non-specific infections. Today it is more appropriate to differentiate tuberculosis from pyogenic . Staphylococcus Streptococcus E. coli fungal . Aspergillus Cryptococcus neoformans parasitic . Echinococcus and postoperative infections. 1024 .