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| The Surgical Technologist | DECEMBER 2020 552 multifactorial, including environmental and genetic factors that eventually lead to abnormal cytokine release. 12 In the lumbar spine, the facet joints are reported to be the most commonly affected, with synovitis and degenerative changes leading to pain and instability. 13 Because facet joints are fibrocartilagi- nous synovial joints, facet erosions are thought to involve a similar mechanism as peripheral joints—synovitis with erosion of cartilage and subchondral bone. 14 Endplate erosions also occur with RA lumbar lesions (Figure 1). Although the disco- vertebral junction is not a synovial joint such as the peripheral or facet joints, histological analysis suggests that erosions of the endplate begin as an enthesopathy at the discovertebral junction. 15 The inflammatory degeneration of collagen at the junction between the disk and the endplates lead to loss of disk space and instability. 14 Other spinal involvements causing symptoms include erosive discitis, spinal stenosis, vertebral collapse, and extension of the inflammatory process from the apophyseal joints. 16 The combination of these changes can result in spinal deformity, including loss of lumbar lordosis and degenerative scoliosis in up to 28 % of patients. 4,17,18 Significance RA has an economic impact on patients’ abilities to sustain employment since patients may experience remission and relapse of their symptoms. 19 Furthermore, patients with RA have higher frequencies of vertebral fractures and higher com- plication rates following surgical interventions compared to patients without RA undergoing similar interventions. 20,21 The management of RA affecting the cervical spine is well described, but there are limited studies discussing the manage- ment of rheumatoid involvement of the lumbar spine. Manifestations General The clinical manifestations of RA are heterogeneous, and the extent of joint involvement and disease progression has been characterized into least erosive disease (LED), more erosive disease (MED), and mutilating disease (MUD), with the latter 2 representing axial joint involvement as well as peripheral joint involvement. 22 Lower back pain occurs in approximately 25 % to 40 % of patients with RA. 4,23 However, Yamada et al 23 found no asso- ciation between lower back pain in patients with RA and radiographic findings. Symptoms possibly related to lumbar lesions and concurrent lumbar stenosis include neurogenic claudication and paresthesias. 4 Case reports and series have also identified incidences of patients reporting lower extre- mity weakness from pathologic fractures, vertebral subluxa- tions caused by mutilating RA, and foraminal stenosis. 24,25 Extra-articular manifestations can be seen with RA as well. There have been case reports of extradural and intradural rheumatoid nodules causing thoracolumbar stenosis and radi- culopathy. 26-28 There have also been case reports of spinal neuroarthropathy secondary to RA, caused by loss of innerva- tion to the spine from cytokine release leading to degenera- tions in disks, end plates, and facet joints resulting in dislocations. 29 Osteoporosis and Fracture Risk There is a higher incidence of osteoporosis and low bone mineral density in RA patients compared with controls. 30 Inflammation related to RA and other inflammatory diseases such as ankylosing spondylitis has been presumed to contribute to lower bone mineral densities and increased risk of vertebral fractures. 31,32 However, the association between the use of corticosteroids in RA and increased risk of vertebral fractures remains controversial. Meng et al 30 found a positive correlation between oral glucocorticoid use and risk of major osteoporotic fractures ( r ¼ 0.701 and P ¼ .006), consistent with the findings of Arai et al 33 findings of 33 % prevalence of vertebral fracture in patients with RA taking glucocorticoids compared with 11 % prevalence of vertebral fracture in patients with RA not taking glucocorticoids. In contrast, in a case-control study with 101 patients with RA and 303 controls, Ghazi et al 34 reported an inverse relationship between glucocorticoid use and prevalence of vertebral fractures, consistent with the report of Ørstavik et al 35 report of 255 patients with RA that found no association between corticosteroid use and incident vertebral deformities. However, it is the senior author’s practice to order a DEXA (dual-energy x-ray absorptiometry) scan prior to any spinal fusion. If osteopenia or osteoporosis is identified, the patient is referred appropriately for initiation of antiresorptive medica- tions or anabolic medications such as teriparatide (Eli Lilly, Indianapolis, IN). Figure 1. Sagittal computed tomography (CT) of the lumbar spine demonstrating L2-L3 endplate erosive changes (arrow). 768 Global Spine Journal 10(6)