Institutional members access full text with Ovid®

Share this article on:

00007632-200007010-0002200007632_2000_25_1736_rombauts_staphylococcus_13report< 69_0_6_4 >Spine© 2000 Lippincott Williams & Wilkins, Inc.Volume 25(13)1 July 2000pp 1736-1738Septic Arthritis of a Lumbar Facet Joint Caused by Staphylococcus aureus[Case Reports]Rombauts, Pascale A. MD*; Linden, Patrick M. MD†; Buyse, Annemie J. MD†; Snoecx, Michel P. MD†; Lysens, Roeland J. MD, PhD*; Gryspeerdt, Stefaan S. MD‡From the *Department of Physical Medicine and Rehabilitation, Faculty of Medicine, University of Leuven, Belgium; the †Departments of Physical Medicine and Rehabilitation and ‡Radiology, City Hospital, Roeselare, Belgium.Acknowledgment date: July 8, 1999.Acceptance date: October 12, 1999.Address reprint requests toPatrick M. Linden, MDDepartment of Physical Medicine and RehabilitationCity HospitalBrugsesteenweg 908800 Roeselare, BelgiumE-mail: patrick.linden@skynet.beDevice status category: 1.Conflict of interest category: 12.AbstractStudy Design. Case report of a 35-year-old woman with septic arthritis of a lumbar facet joint.Objectives. To report a rare case of severe low back pain and the specific differential diagnostic problems.Summary of Background Data. Differential diagnosis between spondylodiscitis and facet joint septic arthritis on a clinical basis is very difficult. The lesions of the joint appear on a plain film only approximately 1.5 months after onset of the symptoms. Although the radionuclide bone scan is sensitive and shows a more laterally and vertically localized uptake than in spondylodiscitis, this technique is not very specific. Computed tomography scan and magnetic resonance imaging are the most reliable investigations even at the very early stages of the disease. Confirmation of the diagnosis has to be obtained by blood cultures or, in exceptional cases, by direct puncture of the joint. Appropriate antibiotic treatment is in most cases sufficient to heal this lesion.Methods. The etiology, clinical presentation, technical examinations, and treatment are reviewed.Results. Computed tomography scan and magnetic resonance imaging complemented by positive blood cultures led to the very early diagnosis of septic arthritis of the lumbar facet joint in this relatively young patient.Conclusions. With our case report we confirm the very small number of data reported in the literature, indicating that infections of the facet joint can be detected at a very early stage using magnetic resonance imaging and computed tomography scan.Septic arthritis of the peripheral joints most frequently involves the knee, followed by the hips, shoulders, wrists, ankles, and elbows, respectively. The sternoclavicular and sacroiliac joints might be preferred spots in intravenous drug users. 1 However, septic arthritis of a lumbar facet joint is rare, with only a few cases reported in literature since 1981. In view of the serious complications with possible fatal outcome, we considered it worthwhile to present our case, especially because of the young age of the patient, 35 years of age, in comparison with the average age of 65 years at onset taken from the literature. 7Case ReportA 35-year-old woman reported acute low back pain radiating to the right flank and anterior side of the right thigh. There was no prior trauma or other known causal factor.The patient described her pain as a continuous, severe pain precipitated by even the smallest movement of the vertebral column. Even at rest, the patient reported pain. At the time of the first consultation, she had not developed any fever.The clinical neurologic investigation was normal, except for the Millgram test (when the patient lies on her back and has to raise both legs),However, which she was unable to perform. The investigation of the active movement of the lumbar vertebral column essentially showed limited and painful anteflexion and left lateroflexion.Hitting the loins caused pain at the right side, and the paravertebral muscles at the right side were hypertonic and painful on palpation.Taking into account the possibility of an undetected inflammatory pathology, a blood specimen was obtained, which showed a significant increase in inflammatory parameters (erythrocyte sedimentation rate 51 mm/h, C-reactive protein 14.8).An echographic examination of the abdomen and a thorax radiograph was negative.A standard radiograph of the lumbar vertebral column was normal. Computed tomography (CT) scan of the lumbar vertebral column from Ll–L5, 4 days after onset of the symptoms, showed an abscess adjoining the intra-apophysal joint L2–L3 at the right side with a clear swelling of the intra-apophysial joint capsule L2–L3, accompanied by swelling and infiltration of the adjacent ligamentum flavum (Figures 1 and 2). Radionuclide bone scan was normal. Additionally, magnetic resonance imaging (MRI) showed a diffuse inflammation of the paraspinal musculature at the lumbar level on the right side, with small micro-abscesses located around the facet joint L2–L3. The global image was compatible with a primary facet arthritis L2–L3 surrounded by a significant inflammatory reaction (Figure 3). Figure 1. Computed tomography (CT) at L2–L3 at the right side. Images obtained after intravenous administration of contrast material show a clear contrast enhancement of the paraspinal muscles, with central hypodensity, surrounding the right apophyseal joint (arrows): abscess formation.Figure 2. CT at L2—L3 at the right side. Images obtained after intravenous administration of contrast material show a clear contrast enhancement of the paraspinal muscles, with central hypodensity, surrounding the right apophyseal joint (arrows): abscess formation. Also note swelling of the ligamentum flavum (arrowhead).Figure 3. Magnetic resonance imaging. T2-weighted sagittal images. There is a clear hyperintense signal intensity of the paraspinal muscles, surrounding the right apophyseal joints, representing diffuse inflammation and abscess formation (arrows).Under echographic guidance, one of the micro-abscesses was punctured. A culture was positive for Staphylococcus aureus. In the meantime, the patient had developed fever, and blood cultures also tested positive for S. aureus. CT scan of the brain, transoesophageal echocardiography, and examination of the eye fundus were negative.Screening for a possible entry portal did not yield any results.The patient was treated for 6 weeks with intravenous antibiotic therapy (Staphycid; SmithKline Beecham, Philadelphia, PA) and complete rest. The patient was allowed to mobilize within acceptable pain limits after the pain decreased.After 6 weeks the patient left the hospital without complications. The antibiotic therapy was continued orally for 4 weeks (Dalacin; Pharmacia/Upjohn, NJ). Control radiography 3 months after onset showed a sharp delineation of the intra-apophysal joint at L2–L3 at the right side (Figure 4). Figure 4. Control radiography 3 months after onset of the symptoms showing a sharp delineation of the intra-apophysal joint at L2–L3 at the right side.DiscussionSeptic arthritis of the lumbar facet joint is rare. Only a few cases have been described in the literature. 1–7 Most cases relate to an infection by hematogenous spread. S. aureus, with the exception of a few cases, is the causal micro-organism. 1,4,7 The portal of entry (e.g., chronic osteomyelitis, dental abscess, urinary infection) is unknown for one third of the patients.Without treatment, the infection spreads through the joint with a possible invasion of the cartilage, the subchondral bone, and possibly the ligaments, eventually resulting in the complete destruction and dislocation of the joint. Occasionally the joint capsule may be punctured, with further spread of pus in the peri-articular tissue, resulting in abscess formation (pyogenic arthritis). Complete destruction of the joint may result in bony ankylosis.Patients present with severe lumbalgia or lumbo-ischialgia and a high fever. Differential diagnosis with spondylodiscitis is hazardous. In lumbar facet joint arthritis, the pain is typically unilateral and is often accompanied by muscular spasm and painful palpation of the paravertebral musculature. 1,4,7 Laboratory tests show an inflammatory blood picture. 4 The causal agent should preferably be obtained from blood cultures because in most cases of facet arthritis a hematogenous spread occurs and radiologic investigations are initially negative. 4,7 Puncture of the joint is only necessary when blood cultures remain negative. 4,7The radiologic abnormalities appear only approximately 1.5 months after the onset of the symptoms. 1,4,7 Initially a swelling of the soft tissues is observed, as well as swelling of the joint capsule as in this case (Figure 2). Later, juxta-articular osteoporosis is seen, a narrowing of the disc space as a consequence of joint destruction, and bone erosion at the surface of the joint. Even the radionuclide bone scan takes a certain latency period to be positive. This is clearly illustrated in the authors’ case, where the radionuclide bone scan remained normal 4 days after onset of the symptoms. If positive, there is a laterally and vertically localized fixation of the vertebral column, in contrast with a spondylodiscitis, where the hyperfixation is localized horizontally. 1,4,7 The exact localization can most clearly be identified on a CT scan and MRI. Lesions of the facet joint are detectable as soon as the first week on MRI and after 15 days of clinical course on CT scan. In cases of septic arthritis, they show typical erosions at the joint surface, swelling of the peri-articular tissue, and loss of local fat tissue. 4 The infection is typically localized at the level of the facet joint L4–L5. 4 MRI shows additional information about the presence of epidural abscess formation or inflammation of the adjacent soft tissues (psoas abscess or abscess in the paravertebral musculature) as in this case. 4Immediate start of tailored intravenous antibiotic therapy is mandatory. The average duration of the antibiotic therapy is approximately 3 to 4 months initially via intravenous infusion and after a few weeks continued orally. 4 In cases of abscess formation with compression of the spinal cord, evacuation and drainage may be necessary. 4Immobilization is indicated, followed by progressive mobilization within acceptable pain limits.The prognosis of septic arthritis is usually favorable. Very infrequently the disease progresses fatally within 24 to 72 hours with high fever, cyanosis, and vascular collapse.Endocarditis is a serious complication of bacteremia caused by S. aureus.Sometimes a mechanical lumbar pain syndrome persists resulting from the acquired joint destruction.In conclusion, septic arthritis of the lumbar facet joint is a rare cause of low back pain. Because of the very serious complications, it is of the utmost importance to ascertain the diagnosis at the earliest possible stage and to start the intravenous antibiotic therapy as soon as possible. This possibility should especially be considered in patients who present with severe, spontaneous onset, unilateral back pain including a nocturnal pain component, and fever.The diagnosis is established on the basis of clinical and radiologic evidence. MRI and CT scan are the best indicated for that purpose. The causative agent is, with only a few exceptions, S. aureus, the identification of which is preferably made indirectly based on the results of the blood cultures. Differential diagnosis with spondylodiscitis is often not possible on the basis of clinical evidence alone. CT scan and MRI are best indicated for that purpose. The prognosis depends primarily on the extent of the inflammation and the speed of starting the antibiotic therapy.AcknowledgmentThe authors thank Wilfried A. Rombauts, PhD, for bibliographical research. References1. Dauwe DM, Van Oyen LL, Samson IR, Hoogmartens MJ. Septic arthritis of a lumbar facet joint and a sternoclavicular joint. Spine 1995; 20:1304–6. [Full Text] [Medline Link] [Context Link]2. Desmoulins F, Clerc D, Marfeuille M, Miquel A, Bisson W. Septic arthritis of the lumbar facet joint [letter]. Rev Rum (Engl ed.) 1997; 64:859–60. [Context Link]3. Douvrin F, Callonec F, Proust F, Janvresse A, Simonet 1, Thiebot J. Arthrite septique interapophysaire lombaire. J Neuroradiol 1996; 23:234–40. [Context Link]4. Ergan M, Macro M, Benhamou C-L, et al. L’arthrite septique intra-apophysaire posterieure, A propos de six cas a l’étage lombaire. Rev Rhum (Fr. ed.) 1997; 64:449–59. [Context Link]5. Fujiwara A, Tamai K, Yamato M, Yoshida H, Saotome K. Septic arthritis of a lumbar joint. Report of a case with early MRI findings. J Spinal Disord 1998; 11:452–3. [CrossRef] [Full Text] [Medline Link] [Context Link]6. Halpin S, Gibson D. Septic arthritis of a lumbar facet joint. J Bone Joint Surg [Br] 1987; 69:457–9. [Context Link]7. Peris P, Brancós MA, Gratacós J, Moreno A, Miró JM, Munõs J. Septic arthritis of a spinal apophyseal joint. Report of two cases and review of the literature. Spine 1992; 17:1517–8. [Context Link] facet joint; septic arthritis; lumbar spine; computed tomography scan; magnetic resonance|00007632-200007010-00022#xpointer(id(R1-22))|11065404||ovftdb|00007632-199506000-00021SL00007632199520130411065404P56[Full Text]|00007632-200007010-00022#xpointer(id(R1-22))|11065405||ovftdb|00007632-199506000-00021SL00007632199520130411065405P56[Medline Link]|00007632-200007010-00022#xpointer(id(R5-22))|11065213||ovftdb|00002517-199810000-00014SL0000251719981145211065213P60[CrossRef]|00007632-200007010-00022#xpointer(id(R5-22))|11065404||ovftdb|00002517-199810000-00014SL0000251719981145211065404P60[Full Text]|00007632-200007010-00022#xpointer(id(R5-22))|11065405||ovftdb|00002517-199810000-00014SL0000251719981145211065405P60[Medline Link]9811108Septic Arthritis of a Lumbar Facet Joint Caused by Staphylococcus aureusRombauts, Pascale A. MD; Linden, Patrick M. MD; Buyse, Annemie J. MD; Snoecx, Michel P. MD; Lysens, Roeland J. MD, PhD; Gryspeerdt, Stefaan S. MDCase Reports1325