Abstract
Purpose
Distinguishing between sequestered disc fragments and tumours remains a diagnostic challenge, but one of paramount importance given the surgical management of these two clinical entities varies dramatically.
Methods
Our experience over the last 3 years in managing this clinical challenge was analyzed.
Patients referred to the regional neurosurgical unit for evaluation of possible spinal tumours whose imaging and clinical findings were atypical, were prospectively identified and the medical notes, operative records and MR imaging reviewed.
Results
This is the single largest series of patients presenting as tumors that were later determined to be sequestered disc fragments. 17 patients(8 female and 9 male) were identified. The median age was 54 years (range 35-77) and the mean follow up time 20 months. The most common location (16/17) for discs mimicking tumours in our series was in the lumbar spine. The major differential diagnosis was of nerve sheath tumours, followed by metastasis.
The signal characteristics of the lesions and contrast enhancement were variable. 35% of patients had the lesion surgically excised and the diagnosis of intervertebral disc made intraoperatively or on histology. The remainder were monitored clinically and with MR imaging, and required no surgical intervention in the follow up period. The features that favoured a diagnosis of disc rather than tumour included a rapid onset of symptoms and abatement of pain with time. Radiologically, sequestered disc was more likely if the lesion demonstrated contiguity with the disc space, the presence of other degenerate discs, no foraminal exit widening, and the absence of central enhancement.
Conclusion
Urgent surgery is not mandatory and in our series a “watch and wait” approach was utilized safely. When atypical clinical and imaging findings are present in patients referred for management of spinal tumours, sequestered disc fragments should be considered as a possibility.
