The imaging and management of nonconsecutive pars interarticularis defects: a case report and review of literature

Diagnostic Accuracy of Magnetic Resonance Imaging and Computed Tomography Scan in Young Athletes With Spondylolysis

The objective of this study was to determine diagnostic accuracy of magnetic resonance imaging (MRI) and computed tomography (CT) scans in young athletes diagnosed with spondylolysis. A cross-sectional study was used. Twenty-two young athletes (14.7 ± 1.5 years) were diagnosed as spondylolysis based on a single-photon emission CT. Following the diagnosis, participants underwent MRI and CT scan imaging tests on the same day. The sensitivity and false-negative rate of the MRI and CT scans were analyzed. MRI test confirmed 13 (+) and 9 (-) results while CT test showed 17 (+) and 5 (-) results. The sensitivity and false-negative rate of MRI were, respectively, 59.1% (95% confidence interval [CI] = 36.7% to 78.5%) and 40.9% (95% CI = 21.5% to 63.3%). Furthermore, the sensitivity and false-negative rate of CT scan were 77.3% (95% CI = 54.2% to 91.3%) and 22.7% (95% CI = 0.09% to 45.8%). Our results indicated that CT scan is a more accurate imaging modality to diagnose spondylolysis compared with MRI in young athletes.

A Case of Nonconsecutive Multiple-level Lumbar Spondylolysis Successfully Treated with Single-level Repair of the Pars Interarticularis

Lumbar spondylolysis is commonly recognized at a single-level of the lumbar spine and frequently affects the L5 pars interarticularis unilaterally or bilaterally. Some reports have described multiple-level spondylolysis, most cases of which occur at consecutive lumbar segments. We herein present a rare case of lumbar spondylolysis involving nonconsecutive multiple-level segments; only eight such cases have been reported previously. A 38-year-old man presented with a 10-month history of chronic severe low back pain. Lumbar flexion–extension radiographs and computed tomography revealed spondylolysis at the level of L3 and L5, whereas no spondylolisthesis was present and the intervertebral disc spaces were maintained at all levels. Because 6 months of conservative management failed and repeated diagnostic blocks confirmed that the fracture of the L3 pars interarticularis was generating pain, repair of the bilateral L3 pars interarticularis with the smiley face rod method was performed. At the last follow-up 1 year after surgery, the patient had resumed normal life as a laborer and reported no back pain.

Atypical, unusual, and misleading imaging presentations of spondylolysis

Although lumbar spondylolysis is a widely known and easily recognizable condition in its typical presentation, there are some less well-known forms that may occasionally be challenging and/or demand special attention on imaging. Examples include: acute and/or incomplete lesions; unilateral defects; lesions at unusual levels (cervical, upper lumbar, and multi-level spondylolyses); iatrogenic lesions; non-isthmic spondylolysis; and spondylolysis related to underlying diseases. In addition to their atypical, uncommon or confusing imaging presentations, these forms of spondylolysis are far rarer than the classic type and have been described, to a great extent, in the surgical literature, thus reducing the awareness of radiologists about them and raising the potential for misdiagnosis and inadequate treatment. In this review the authors address these special manifestations of spondylolysis, stressing the more important features to be considered in the differential diagnosis and the impact of a precise diagnosis of spondylolysis on the patient's care.