Abstract
Background
Joint effusions identified by MRI may accompany osteomyelitis and determining whether the joint effusion is septic or reactive has important implications on patient care.
Objective
Determine the incidence of epiphyseal marrow edema, joint effusions, perisynovial edema and epiphyseal non-enhancement in the setting of pediatric metaphyseal osteomyelitis and whether this may be used to predict coexisting septic arthritis.
Materials and methods
Following IRB approval, we retrospectively evaluated children who underwent MRI and orthopedic surgical consultation for suspected musculoskeletal infection between January 2011 and September 2013. Criteria for inclusion in the study were microbiologically/pathologically proven infection, MRI prior to surgical intervention, long bone involvement and age 0–18 years. MRI exams were independently reviewed by two faculty pediatric radiologists to confirm the presence of appendicular metaphyseal osteomyelitis, to evaluate extent of edema, to determine subjective presence of a joint effusion and to assess perisynovial edema and epiphyseal non-enhancement. Any discrepant readings were reviewed in consensus. Charts and operative notes were reviewed to confirm the diagnosis of osteomyelitis and septic arthritis.
Results
One hundred and three joints with metaphyseal osteomyelitis were identified (mean age: 7.1 years; M:F 1.3:1), of whom 53% (55/103) had joint effusions, and of those, 75% (41/55) had surgically confirmed septic arthritis. The incidence of coexisting septic arthritis was 40% in the setting of epiphyseal edema, 74% in epiphyseal edema and effusion, 75% with perisynovial edema, 76% with epiphyseal non-enhancement and 77% when all four variables were present. Of these, the only statistically significant variable, however, was the presence of a joint effusion with a P-value of <0.0001 via Fisher exact test. Statistical significance for coexisting septic arthritis was also encountered when cases were subdivided into intra-articular vs. extra-articular metaphyses (P-value = 0.0499). No statistically significant difference was found between patients younger than 24 months and those older than 24 months.
Conclusion
Patients with joint effusions identified by MRI, in the setting of metaphyseal osteomyelitis, should be presumed to have septic arthritis until proven otherwise. Epiphyseal extension of edema, perisynovial edema and epiphyseal non-enhancement in the setting of metaphyseal osteomyelitis are not helpful predictors in differentiating reactive and pyogenic joint effusions. Osteomyelitis at a site with an intra-articular metaphyses, however, is more likely to have concurrent septic arthritis.
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References
Dodwell ER (2013) Osteomyelitis and septic arthritis in children: current concepts. Curr Opin Pediatr 25:58–63
Kan JH, Young RS, Yu C et al (2010) Clinical impact of gadolinium in the MRI diagnosis of musculoskeletal infection in children. Pediatr Radiol 40:1197–1205
Kan JH, Hilmes MA, Martus JE et al (2008) Value of MRI after recent diagnostic or surgical intervention in children with suspected osteomyelitis. AJR Am J Roentgenol 191:1595–1600
Pääkkönen M, Peltola H (2013) Treatment of acute septic arthritis. Pediatr Infect Dis J 32:684–685
Liu C, Bayer A, Cosgrove SE et al (2011) Clinical practice guidelines by the Infectious Diseases Society of America for the treatment of methicillin-resistant Staphylococcus aureus infections in adults and children: executive summary. Clin Infect Dis 52:285–292
Montgomery CO, Siegel E, Blasier RD et al (2013) Concurrent septic arthritis and osteomyelitis in children. J Pediatr Orthop 33:464–467
Dartnell J, Ramachandran M, Katchburian M (2012) Haematogenous acute and subacute paediatric osteomyelitis. J Bone Joint Surg 94B:584–595
Karchevsky M, Schweitzer ME, Morrison WB et al (2004) MRI findings of septic arthritis and associated osteomyelitis in adults. AJR Am J Roentgenol 182:119–122
Yang WJ, Im SA, Lim GY et al (2006) MR imaging of transient synovitis: differentiation from septic arthritis. Pediatr Radiol 36:1154–1158
Trueta J, Agerholm M (1948) Acute haematogenous osteomyelitis; diagnosis and treatment. Overseas Postgrad Med J 2:311–322
McCarthy J, Dormans J, Kozin S (2005) Musculoskeletal infection in children: basic treatment principles and recent advancements. Instr Course Lect 54:515–528
Pääkkönen M, Peltola H (2013) Bone and joint infections. Pediatr Clin N Am 60:425–436
Offiah AC (2006) Acute osteomyelitis, septic arthritis and discitis: differences between neonates and older children. Eur J Radiol 60:221–232
Frank G, Mahoney HM, Eppes SC (2005) Musculoskeletal infections in children. Pediatr Clin N Am 52:1083–1106
Jackson MA, Burry VF, Olson LC (1992) Pyogenic arthritis associated with adjacent osteomyelitis: identification of the sequela-prone child. Pediatr Infect Dis J 11:9–13
Perlman MH, Patzakis MJ, Kumar PJ et al (2000) The incidence of joint involvement with adjacent osteomyelitis in pediatric patients. J Pediatr Orthop 20:40–43
Song KM, Sloboda JF (2001) Acute hematogenous osteomyelitis in children. J Am Acad Orthop Surg 9:166–175
Sucato DJ, Schwend R, Gillespie R (1997) Septic arthritis of the hip in children. JAAOS 5:249–260
Wang CL, Wang SM, Yang YJ et al (2003) Septic arthritis in children: relationship of causative pathogens, complications, and outcome. J Microbiol Immunol Infect 36:41–46
Welkon CJ, Long SS, Fisher MC et al (1986) Pyogenic arthritis in infants and children: a review of 95 cases. Pediatr Infect Dis 5:669–676
Strouse PJ, Londy F, DiPietro MA et al (1999) MRI evaluation of infectious and non-infectious synovitis: preliminary studies in a rabbit model. Pediatr Radiol 29:367–371
Graif M, Schweitzer ME, Deely D et al (1999) The septic versus nonseptic inflamed joint: MRI characteristics. Skelet Radiol 28:616–620
Kim EY, Kwack KS, Cho JH et al (2012) Usefulness of dynamic contrast-enhanced MRI in differentiating between septic arthritis and transient synovitis in the hip joint. AJR Am J Roentgenol 198:428–433
Stans AA (2014) Muskuloskeletal infection. In: Lovell W, Weinstein SL, Flynn JM (eds) Lovell and Winter’s pediatric orthopaedics, 7th edn. Wolters Kluwer Health/Lippincott Williams & Wilkins, Philadelphia
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The authors would like to sincerely extend their appreciation to Robbie Schallert for his contribution to data organization and statistical analysis.
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K. Schallert, E., Herman Kan, J., Monsalve, J. et al. Metaphyseal osteomyelitis in children: how often does MRI-documented joint effusion or epiphyseal extension of edema indicate coexisting septic arthritis?. Pediatr Radiol 45, 1174–1181 (2015). https://doi.org/10.1007/s00247-015-3293-0
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DOI: https://doi.org/10.1007/s00247-015-3293-0