Background: The simultaneous occurrence of spina bifida occulta (SBO) and spondylolysis has been noted previously. The occurrence of SBO and spondylolysis are approximately 17% and 5% respectively.

Aims: The aim of this study was to determine the incidence of SBO when a symptomatic spondylolysis has been proven.

Method: Analysis of four years of lumbar spine CT scans was performed. Patients with spondylolysis or spondylolisthesis caused by a pars defect were identified. These patients’ CT images were then reviewed to establish the patients who also had SBO.

Results: In this unit 650 CT scans of lumbar spines were performed in the last five years. Of these scans 100 (15%) were found to have a pars defect. The average age was 34.6. On CT 30 (30%) patients were shown to have SBO. Of the total 23 were under 18 years old and 13 (56%) of these patients had SBO associated with the spondylolysis. In the over 18 year olds 21 (27%) patients had SBO associated with spondylolysis.

On review of the 550 other scans the average age was 51.9 years old. The incidence of SBO within this group is 10%. Only 6% of these patients were under 18. Out of these 33 patients 30.3% (10 patients) had SBO. Over 18 the incidence of SBO was only 8.5%.

Conclusions: Our results indicate that the occurrence of SBO within the group with a spondylolysis is much higher than in the group where no spondylolysis is present. There is higher incidence of SBO in the younger patients with spondylolysis. 56% of paediatric patients with symptomatic spondylolysis will have SBO. Clinicians should be aware of this fact preoperatively to decide on the technique of repair of the symptomatic lysis.

Background: Radicular pain has been reported even in the absence of a compressive lesion. It has been postulated that annular tears provide a conduit for pro-inflammatory substances, which can leak around the nerve root causing radiculitis. A link between the side of back pain and the side of the annular tear has been reported.

Objective: To establish whether the side of the annular tear may influence the side of the leg in a non-compressive setting.

Methods and patients: We identified 121 patients from the patients referred to our unit with back and radicular leg pain. The mean age of the cohort was 50 yrs and 49% were male. All these patients were investigated with an MRI scan that demonstrated no compression of the nerve root. We used strict exclusion criteria to exclude the patients with any neural compression, previous lumbar operation, degenerative deformity or an associated pathology such as peripheral neuropathy.

Results: The annular pathology was described as annular tears (47 patients) and non compressive disc bulges (106 patients). The odds ratio for the concurrence of an annular tear causing ipsilateral leg pain is 1.05 and for a non-compressive disc bulge causing ipsilateral leg pain is 2.14

Conclusion: A non-compressive disc bulge is more likey to cause radicular symptoms than an annular tear. Though, both these annular lesions can cause ipsilateral nerve root symptoms.

Objective: To assess the correlation between the side of the annular pathology and the radicular symptoms, in the absence of a compressive root lesion.

Materials and Methods: 121 patients underwent MRI scan fro axial back and radicular symptoms. The mean age was 49.9 yrs (24–80). The sex distribution was equal. We excluded the patients that had a compressive lesion, previous operations, spinal deformity, spondylolyses, an underlying pathology (tumour, trauma or infection) or a peripheral neuropathy. Annular pathology was documented as annular tear or a non-compressive disc bulge with its location and side. We also recorded marrow endplate changes and facet arthrosis.

Results: Bilateral radicular symptoms were reported in 16 (13.2%): right side in 33 (27.3%) and left in 47 (38.8%) patients. Additionally, 82 patients (67.8%) had axial back pain. 33 patients (27.3%) were noted to have a right sided annular pathology (tear or bulge) and 72 (59.5%) had a left sided annular lesion. 21 patients (17.4%) had a central annular tear and 43 (35.5%) had a generalised disc bulge. 14 patients (11.6%) with right sided symptoms also had annular pathology, while 38 patients (31.4%) with left sided symptoms had a left sided annular lesion. There was no statistical correlation between the side of symptoms and the side of the lesion (r = −0.00066, p=0.994), any particular annular pathology (annular tear r=0.085, p=0.35; disc bulge r-0.083, p=0.36). There was no correlation between the axial back pain and the annular pathology (r=0.004; p=0.97) and facet joint or marrow end plate changes (r= −,29, p=0.76).

Conclusions: Although annular pathology can cause the radicular symptoms, our results suggest that they do not influence the side of the symptoms.