Eleven cases of lumbar juxtafacet cyst were consecutively treated via a contralateral sublaminar endoscopic approach using percutaneous biportal endoscopic surgery. Postoperative magnetic resonance imaging (MRI) scans were evaluated on postoperative Day 1 for optimal removal of the cysts and neural decompression status. Clinical findings were evaluated in the preoperative and postoperative periods using a visual analog scale (VAS) for the legs and the Oswestry Disability Index (ODI).

A total of 10 lumbar juxtafacet cysts in ten patients were treated using the contralateral sublaminar biportal endoscopic approach. Postoperative MRI depicted complete removal of the juxtafacet cysts and optimal neural decompression of the treated segments in all patients. Preoperative VAS and ODI scores improved significantly after surgery: VAS scores changed from 7.64 ± 0.71 preoperatively to 1.63 ± 1.28 at the last follow-up visit (p < 0.05), while ODI scores changed from 45.35 ± 16.15 to 15.82 ± 10.21 (p < 0.05). The mean operative time was 60.1 ± 23.4 minutes.

Considering the outcomes of this study, a contralateral sublaminar approach using percutaneous biportal endoscopy may be an alternative treatment for symptomatic lumbar juxtafacet cysts. This approach may minimize iatrogenic facet violation and traumatization of posterior musculoligamentous structures ¹⁾.

36 consecutive patients with JFC and the same number of controls, with degenerative diseases without JFC were match paired for demographics and spine segment. Parameter assessment was by T2-weighted axial MRI scans. JFC diagnosis was confirmed histopathologically. Group comparison was by Student's t-test for continuous variables and X(2) for categorical variables. RESULTS: Nineteen female and 17 male patients, aged between 45 and 85 years (mean 67.19±10.3 years) had a mean JFC size of 9.26±4.8mm occurring most frequently in the segment L4-L5 (75% n=25) and on the left side (61%). Mean FJ orientation of the study group was significantly more coronal compared to controls (left side 42° vs 36°, p<0.02*, 95% confidence interval: 0.9-11.5 and right side 43° vs 37°, p<0.02*, 95% confidence interval: 0.6-10.6 respectively). However, individual intersegmental analysis for study group patients showed the JFC bearing side to be significantly more sagittally oriented 40°±11.2° compared to 45°±13.2° for the side without FJC (p<0.03*, 95% confidence interval: 8.1-1.7). 50% of the study group showed FJ asymmetry compared to 30% in controls, with a trend for FJ tropism (p<0.07). Severe (grade 3) FJ arthritis was significantly more predominant in the study group 23/33 (p<0.001*) as compared to controls. CONCLUSIONS: Compared to a control group, JFC occurrence is associated with significant higher rates of arthritis and coronally orientated FJ. At intersegment comparison within the same patient cysts located in more sagittally orientated FJ and the asymmetric segments show a trend for FJ tropism ²⁾.

One observer undertook a review of MRI of the lumbar spine from one facility in a series of 303 patients referred mostly for back pain or radiculopathy. The presence of lumbar facet joint synovial cysts, their relationship to the facet joint, the degree of associated facet joint osteoarthritis, the presence of spondylolisthesis, and the degree of associated disc degeneration were recorded.

Seven anterior cysts (prevalence = 2.3%) were identified, only two of which did not clearly cause nerve root compression. Twenty-three posterior cysts in 22 patients (prevalence = 7.3%) were identified. Statistically significant associations with increased frequency and severity of facet joint osteoarthritis and with spondylolisthesis were demonstrated compared to patients without cysts.

Both anterior and posterior lumbar facet joint synovial cysts are rare. Posterior cysts are more common than anterior cysts. Both types of cysts are related to facet joint osteoarthritis but not to disc disease ³⁾

Spinal instability may be a cause of juxtafacet cyst formation and the pain and disability that occur after surgical excision of the cyst. To determine the role of instability, a retrospective review of charts identified 60 facet cysts in 56 patients treated over a 6-year period. Three patients developed an asynchronous cyst at the same level but on the opposite side of the previously resected cyst and one patient had a recurrent cyst in the same location. Forty-one cysts were present in patients with radiculopathy and 16 in patients with neurogenic claudication. Two patients presented with myelopathy and one had cauda equina syndrome. Thirty-six of the 60 cysts were located at L4-5, the most mobile segment. Fifteen patients had spondylolisthesis, of whom two experienced worsening spondylolisthesis postoperatively. Seven patients had scoliosis and 20 had systemic arthritis. Fifty-five cysts were resected via mesial facetectomy. Six of the patients undergoing this procedure had transverse process fusions at initial surgery for preoperative instability. Two others required fusion for post-operative instability and increased spondylolisthesis. Follow-up review was available in 95% of patients with an average duration of 12 months. Forty patients had excellent relief of symptoms, 12 had occasional back pain, and one patient did poorly. Flexion/extension views of the spine are recommended both pre- and postoperatively to identify the need for fusion in patients with juxtafacet cysts ⁴⁾.

Over the past 18 months Eyster and Scott. have encountered 11 cases of symptomatic lumbar synovial cysts. This experience occurred during a period during which some 1,800 lumbar computed tomographic scans were done. The apparent increased incidence of these lesions is most likely due to the increased diagnostic ability made possible by the advent of high-resolution computed tomography and magnetic resonance imaging. This is a report and discussion of our 11 cases with a review of the literature. There is nothing distinctive in the physical findings or in the histories of our patients, but we have found, as have others, that high-resolution computed tomographic scanning and magnetic resonance imaging significantly enhance the diagnosis of such lesions ⁵⁾.

Intraspinal synovial cysts can be accurately diagnosed by computed tomography (CT). Lemish et al., report ten cases of lumbar intraspinal synovial cysts (LISC) that highlight the clinical and radiologic features ⁶⁾

13 patients with synovial or ganglion cysts of the spinal facet joints causing nerve root compression. These cysts were found in both the cervical and the lumbar spine, and the anatomical location of each cyst corresponded to the patient's signs and symptoms. In no case was there evidence of intervertebral disc abnormality found at operation. The patients ranged from 49 to 77 years of age and included 4 men and 9 women. Radiographic evidence of facet degenerative change and degenerative spondylolisthesis was frequently but not invariably noted. The extradural defects defined with positive contrast myelography or postmyelography computed tomographic scanning were usually posterior or posterolateral to the common dural sac and were misinterpreted as extruded discs in the majority of cases. Treatment consisted of laminectomy and surgical excision of cysts. All patients reported improvement or resolution of their presenting symptoms ⁷⁾.

Four patients who had low-back pain and sciatica were diagnosed as having a lumbar intraspinal extradural synovial cyst adjacent to a facet joint between the fourth and fifth lumbar vertebrae. The patients ranged in age from forty-nine to seventy-one years, and the symptoms and signs involved the fourth or fifth lumbar-nerve roots. Roentgenographically, degeneration of the intervertebral discs and facet joints was noted in every patient. Degenerative spondylolisthesis was also a frequent finding. Myelography and computed tomographic scans aided in diagnosis, revealing a soft-tissue lesion, occasionally rimmed with calcification, adjacent to the involved facet joint. The treatment was surgical excision of the cyst, as well as complete laminectomy if there was concomitant spinal stenosis. Follow-up, ranging from eighteen to twenty-five months, revealed complete resolution of the sciatica in all patients ⁸⁾.