Treatment Of Foraminal Stenosis Research Articles

Comparison between Anterior Cervical Decompression with Fusion and Posterior Cervical Fusion with Wide Facetectomy for Treatment of Severe Bony Foraminal Stenosis.

ObjectiveTo compare the anterior cervical discectomy and fusion (ACDF) and posterior cervical fusion (PCF) with wide facetectomy in the treatment of parallel-shaped bony foraminal stenosis (FS). MethodsThirty-six patients underwent surgery due to one-or-two levels of parallel-shaped cervical FS. ACDF was performed in 16 patients, and PCF using CPS was performed in 20 patients. All patients were followed up at 1, 3, 6, and 12 months postoperatively. Standardized outcome measures such as Numeric rating scale (NRS) score for arm/neck pain and Neck disability index (NDI) were evaluated. Cervical radiographs were used to compare the C2–7 Cobb’s angle, segmental angle, and fusion rates. ResultsThere was an improvement in NRS scores after both approaches for radicular arm pain (mean change -6.78 vs. -8.14, p=0.012), neck pain (mean change -1.67 vs. -4.36, p=0.038), and NDI score (-19.69 vs. -18.15, p=0.794). The segmental angle improvement was greater in the ACDF group than in the posterior group (9.4°±2.7° vs. 3.3°±5.1°, p=0.004). However, there was no significant difference in C2–7 Cobb angle between groups (16.2°±7.9° vs. 14.8°±8.5°, p=0.142). As a complication, dysphagia was observed in one case of the ACDF group. ConclusionIn the treatment of parallel-shaped bony FS up to two surgical levels, segmental angle improvement was more favorable in patients who underwent ACDF. However, PCF with wide facetectomy using CPS should be considered as an alternative treatment option in cases where the anterior approach is burdensome.

Unilateral Stand-Alone Cage for the Treatment of Foraminal Stenosis in Patients with Degenerative Scoliosis. A Case Series of 20 Patients

Object: Neuroforaminal stenosis has been documented frequently in patients with degenerative lumbar scoliosis. Pedicle screw fixation with posterior lumbar interbody fusion is usually performed although a debate has been started on the need for unilateral or bilateral screws, or interbody fusion only. Trabecular Metal is a porous tantalum biomaterial with good osteoconductive properties, which may be suitable for unilateral interbody fusion aiming at enlargement of neuroforamen. Methods: From July 2011 until January 2013, 20 consecutive patients with degenerative scoliosis-related foraminal stenosis were treated with unilateral stand-alone Trabecular Metal cages (Zimmer TM 500) without additional pedicle screw fixation. All patients presented with leg pain, with or without low back pain. Patients underwent CT and MRI to confirm neuroforaminal stenosis on the concave side of the degenerative scoliosis. All patients were followed-up and examined at 2 months after surgery (follow-up moment 1). Long-term follow-up (moment 2; mean 36 months) was available of 17 patients; 2 patients died of unrelated disease and 1 patient was lost to follow-up. On both follow-up moments, neutral and dynamic flexion-extension images were documented. Based on these images, the position of the cage was determined and the Cobb’s angle of the segmental scoliosis (angle between the cranial endplate of the upper vertebral body and the caudal endplate of the lower vertebral body) was measured. The clinical outcome was measured by the patients’ global perceived recovery according to the 7-point Likert scale; “complete recovery” and “almost complete recovery” were determined as good results. Results: Most of the patients were operated on L3L4 and L4L5 (70%). The mean duration of surgery was 56 ± 15 minutes. Surgical complications occurred in 5 patients, namely cerebrospinal fluid leakage (4 patients) and nerve root injury (1 patient) with sensory deficit. Good outcome (Likert 1 or 2) was reported by 14 patients (70%) on the shortterm follow-up (moment 1), and by 9 patients (53%) on the long-term follow-up (moment 2). Whenever Likert 1-3 was dichotomized, 95% of the patients on the short-term and 83% of the patients on the long-term reported at least some benefit from the operation. The mean Cobb’s angle improved significantly from 13.4 ± 5.1o pre-operatively, to 6.1 ± 3.5o at moment 1, and 7.1 ± 3.6o at moment 2 (P < 0.001). On follow-up moment 1 and 2, radiographic examination showed subsidence in 3 and 9 patients, respectively. Pseudarthrosis around the stand-alone cage was only seen at follow-up moment 2 in 3 patients. Conclusions: Instrumented fusion with bilateral pedicle screw fixation and interbody fusion may not always be necessary in patients with scoliosis-related foraminal stenosis. Unilateral stand-alone TM cages could be an alternative strategy in a subgroup of patients leading to correction of Cobb’s angle and improvement of symptoms in most cases. However, the long-term result is moderately satisfying and could be explained by the development of cage subsidence over time.

Outcome Measures of an Intracanal, Endoscopic Transforaminal Decompression Technique: Initial Findings from the MIS Prospective Registry.

Minimally invasive transforaminal endoscopic procedures can achieve spinal decompression through either direct or indirect techniques. Subtle variations in trajectory of the surgical corridor can dictate access to the pathologic tissue. Two general strategies exist: the intradiscal "inside-out" technique and the extradiscal, intracanal (IC) technique. The IC technique utilizes a more lateral transforaminal approach than the intradiscal technique, which allows for a more direct decompression of the spinal canal. This study is an assessment of IC patient outcome data obtained through analysis of a previously validated MIS Prospective Registry. Post-hoc analysis was performed on the MIS Prospective Registry database containing 1032 patients. A subgroup of patients treated with the endoscopic IC technique was identified. Patient outcome measures after treatment of symptomatic disk herniation and neuroforaminal stenosis were evaluated. A total of 86 IC patients were analyzed. Overall, there was significant improvement in employment and walking tolerance as soon as 6 weeks post-op as well as significant one year VAS and ODI score improvement. Subanalysis of IC patients with two distinct primary diagnoses was performed. Group IC-1 (disc herniation) showed improvement in ODI and VAS back and leg outcomes at 1 year post-op. Group IC-2 (foraminal stenosis) showed VAS back and leg score improvement at one year post-op but did not demonstrate significant improvement in overall ODI outcome at any time point. The one year re-operation rate was 2% (1/40) for group IC-1 and 28% (5/18) for group IC-2. The initial results of the MIS Registry IC subgroup show a significant clinical improvement when the technique is employed to treat patients with lumbar disc herniation. The treatment of foraminal stenosis can lead to improved short-term clinical outcome but is associated with a high re-operation rate at 1 year post-op.

Endoscopic foraminotomy using a microendoscopic discectomy system in cadaveric specimens

Although the anterior approach is more commonly performed for the treatment of cervical disc disease, the posterior approach has distinct advantages in selected cases of foraminal stenosis and posterolateral disc herniation. The authors performed cervical key hole foraminotomies using a microendoscopic discectomy (MED) system in four cadaveric cervical spine specimens to evaluate this minimally invasive surgical approach for cervical disc diseases. The amount of bone decompression achieved by using the MED system was compared with that achieved by using the open foraminotomy procedure in each cadaveric specimen. Three noncontiguous cervical nerve roots were selected between C-3 and C-8 in each specimen and were decompressed using the MED system on one side and using the open foraminotomy procedure on the contralateral side. Postoperative computerized tomography (CT) myelography showed that adequate bone decompression was achieved by using either the MED or open procedure in all specimens. Postoperatively, open dissection was performed to confirm and compare the amount of decompression in both the MED and open procedures. The laminotomy size (vertical and transverse diameter), the length of decompressed nerve root, and the proportion of removed facet joint were measured on every operative level. The average vertical diameter of laminotomy area and the percentage of facet removed were significantly greater in the MED procedure than the open procedure (p &lt; 0.05). The transverse diameter of the laminotomy area and the average decompressed root length were not significantly different between MED and open surgery. The authors conclude that endoscopic cervical foraminotomy using the MED system is a feasible procedure and may be clinically applicable in the treatment of foraminal stenosis and laterally located cervical disc herniation.