1. Centro Hospitalar Lisboa Central - Hospital Curry Cabral, Lisboa, Portugal
2. Hospital de Vila Franca de Xira, Vila Franca De Xira, Portugal
3. Centro Hospitalar de Setúbal - Hospital Ortopédico de Sant'Iago do Outão, Setubal, Portugal
4. Centro Hospitalar Barreiro Montijo, Barreiro, Portugal
5. Centro Hospitalar Lisboa Central - Hospital D. Estefania, Lisboa, Portugal
- Poster, Congresso Europeu de Ortopedia, Viena, 29 de Maio a 1 de Junho de 2017
Background: Facet joint septic arthritis is a rare condition, first described in 1987. It mostly affects adults and only six paediatric cases have been reported so far. The most common cause is hematogenous contamination, although direct inoculation has also been reported. According to the literature, 90% of locations are lumbar and the most commonly isolated microorganism is Staphylococcus aureus. Diagnosis of this rare clinical condition is difficult and often delayed as it can mimic other causes of back pain. Radiological features appear very late in the disease, by which time it can give rise to paraspinal or epidural abscess. MRI is necessary to confirm the topographic diagnosis, define soft tissue involvement and rule out differential diagnoses.
Case Presentation: A previously healthy 12-year- old patient presented to the Emergency Department (ED) with chief complaint of low back pain (VAS 7/10) radiating to the right flank, accompanied by fever and headaches with 24h of evolution. Past medical history was positive for an upper respiratory infection, one week earlier, and recent contact with a case of viral gastroenteritis (his brother). No trauma, gastrointestinal or urinary symptoms and recent weight loss were referred. On physical exam, patient had pain exacerbated by all movements located to the upper lumbar spine and right flank, without overlying skin inflammatory signs. Analytically, he had elevated C-reactive protein (CRP = 98,8 mg/dL) and erythrocyte sedimentation rate (ESR = 15mm/h) without leukocytosis. Abdominal, pelvic and renal etiologies were excluded after Paediatric Surgery observation and a normal ultrasound (US). AP and lateral lumbar spine radiographs were also normal and patient was discharged with recommendation for symptomatic treatment and rest. Nine days later, after a transient relief period, symptoms relapsed and pain was more intense and debilitating. Due to such clinical aggravation and concomitant further elevation of CRP and ESR, an urgent MRI was ordered. A quadratus lumborum and erector spinae abscess was revealed, originating from a right interapophyseal L2-L3 septic arthritis.
Outcomes: Parenteral gentamicin and flucloxacilin were initiated and maintained for 11 days, with progressive clinical improvement. Ten days after admission a 23x6x15mm collection was still detectable on US and a transcutaneous drainage was performed. Since no agent was identified in both blood and pus cultures, empiric oral flucloxicilin was maintained for an additional 4 weeks after discharge. Outpatient seriated US showed progressive abscess remission. No recurrence or residual deformity was registered after 2 years of follow-up.
Discussion: Septic arthritis of the lumbar facet joints is a rare disease, particularly in children. Late diagnosis is common, due to its unspecific and sometimes indolent presentation. In this case, presence of lumbar pyomyositis, at time of diagnosis, was probably a result of the delayed treatment, allowing for infection dissemination to adjacent muscle groups. Therefore, detection of paraspinal muscle abscesses should always raise the suspicion index for a concomitant spinal infection. Early recognition of these conditions is important, as failure to acknowledge them can lead to inappropriate management and complications such as epidural abscess, neurologic deficits and even death. Treatment with empirical antibiotherapy is usually satisfactory if started in the early stages, but if there are purulent collections or intraspinal affectation, drainage or surgical debriding may be necessary.
Palavras-chave: Alignmnet, Total Knee Arthroplasty, Femoral Cut