Upper facet joint en bloc resection for the treatment of thoracic myelopathy caused by ossification of the ligamentum flavum

A systematic review of surgical procedures on thoracic myelopathy

Purpose

The surgical treatment of thoracic myelopathy is still controversial and also a challenge for spine surgeons. Therefore, the objective of this study was to review the related literature on the surgical treatment of thoracic myelopathy and try to define treatment guidelines for spine surgeons on thoracic myelopathy.

Methods

Relevant literatures were searched based on the PubMed, EMBASE, and Cochrane Library between January 2008 and December 2018. Some data on the characteristics of patients were extracted, including number of patients, mean age, surgical procedures, blood loss, complications, and pre-/post-operation modified JOA score. Recovery rate was used to assess the effect of surgery outcome, and the safety was evaluated by blood loss and incidence of complications.

Results

Thirty-five studies met the inclusion criteria and were retrieved. A total of 2183 patients were included in our systematic review, with the average age of 55.2 years. There were 69.8% patients diagnosed as ossification of ligamentum flavum (OLF), 20.0% as ossification of posterior longitudinal ligament (OPLL), 9.3% as disk herniation (DH), and 0.9% as others including diffuse idiopathic skeletal hyperostosis (DISH) and ankylosing spondylitis (AS). The volume of blood loss was more in the treatment of circumferential decompression (CD) than posterior decompression (PD), and the incidence of complications was higher in CD (P < 0.05). The volume of blood loss in minimally invasive surgery (MIS) was lowest and the incidence of complications was 19.2%. Post-operation recovery rate was 0.49 in PD, 0.35 in CD, and 0.29 in MIS while the recovery rate was 0.54 in PD, 0.55 in CD, and 0.49 in MIS at the last follow-up. When focusing on the OLF specifically, incidence of complications in PD was much lower than CD, with less blood loss and higher recovery rate. Focusing on the OPLL specifically, incidence of complications in PD was much lower than CD, with less blood loss while there was no statistical difference in recovery rate between these two methods.

Conclusions

This systematic review showed that posterior decompression for thoracic myelopathy is safer and better than circumferential decompression according to the complication rate and surgical outcome. And we should also consider the location of compression before the operation.

Subsection Laminectomy with Pedicle Screw Fixation to Treat Thoracic Ossification of Ligamentum Flavum: A Comparative Analysis with Lamina Osteotomy and the Replantation Technique

BACKGROUND

There are many surgical procedures that can be used to relieve compression caused by thoracic ossification of the ligamentum flavum (TOLF). The present study aims to retrospectively observe the differences in subsection laminectomy with pedicle screw fixation (SLPF) and lamina osteotomy and replantation with miniplate fixation (LORF) in the treatment of continuous TOLF.

PATIENTS AND METHODS

From March 2014 to October 2017, 61 patients with continuous TOLF underwent SLPF (group A) or LORF (group B). The surgical duration, intraoperative blood loss, change in thoracic kyphosis, and perioperative complications were analyzed. Neurological function was evaluated in accordance with the Japanese Orthopedic Association (JOA) score and the American Spinal Injury Association (ASIA) neurological grading.

RESULTS

The surgical duration, intraoperative blood loss, and postoperative bed-rest duration in group A were significantly lower than those observed in group B (P < 0.05). Both groups demonstrated a significant improvement in JOA score and ASIA grade (P < 0.05). The neurological recovery rate was 69.8% ± 13.5% in group A and 68.5% ± 12.7% in group B (P > 0.05). There was also a significant improvement in ASIA grade at the final follow-up (P < 0.05). During follow-up, the Cobb angle was significantly increased in group B (P < 0.05), whereas no significant difference was observed in group A (P > 0.05). The occurrence rate of perioperative complications was 15.6% (5/32 patients) in group A and 37.9% (11/29 patients) in group B (P < 0.05).

CONCLUSION

Both SLPF and LORF significantly promote recovery of neurological function. SLPF has a shorter surgical duration, less intraoperative blood loss, and a lower complication rate. SLPF is more conducive to the correction of sagittal sequence and maintenance of thoracic stability.

Ossified ligamentum flavum of the thoracic spine presenting as spontaneous intracranial hypotension: case report

Ossification of the ligament flavum in the thoracic spine is an uncommon radiological finding in the Western population but can present with back pain, varying degrees of myelopathy, and even paraplegia on occasion. The authors here present the case of a 50-year-old woman with a history of progressive back pain and symptoms of spontaneous intracranial hypotension who was found to have an ossified ligamentum flavum of the thoracic spine resulting in a dural erosion cerebrospinal fluid leak. Surgery involved removal of the ossified ligament flavum at T10-11, facetectomy, ligation of the nerve root, and primary closure of the dura, which resulted in complete resolution of the patient's symptoms. Radiological, clinical, and intraoperative findings are discussed to assist surgeons with an accurate diagnosis and treatment in the setting of this unusual presentation.

A systematic review of complications in thoracic spine surgery for ossification of ligamentum flavum

STUDY DESIGN

Systematic review.

OBJECTIVES

The aim of this systematic review is to summarize the incidence of complications, to relate complication incidence to procedures performed, to assess the impact of the year of study publication and follow-up duration on complication incidence.

METHODS

The authors conducted the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE searches for relevant literatures. The incidence of complications was summarized. Correlation of the incidence with year of study publications, follow-up duration, and the surgical outcome was statistically evaluated.

RESULTS

A total of 16 studies met our inclusion criteria, including 475 patients. All of these studies were retrospective case series. The mean age of patients ranged from 55 to 64 years. Average follow-up duration ranged from 26 to 65 months. Partial patients in four studies underwent surgeries and reserved posterior structure of the spinal canal. The others underwent operations removing posterior structure of spinal canal. The mean recovery rate from each individual study varied between 31 and 68% and the pooled neurologic function recovery rate was 53% (95% CI: 43-62%). The mean complication rate was 24%. Cerebrospinal fluid leakage was the most reported postoperative complication (19%), then neurologic deterioration (5%). Other complications included local infections, wound dehiscence, increased kyphotic deformity, an hematoma.

CONCLUSIONS

Operations removing posterior structure of spinal canal are the main technique to decompress spinal cord. Cerebrospinal fluid leakage and postoperative neurologic deterioration were the most reported complications.

Surgical Technique for Decompression of Severe Thoracic Myelopathy due to Tuberous Ossification of Ligamentum Flavum

STUDY DESIGN

Retrospective review.

OBJECTIVE

To describe a safe surgical procedure, en bloc resection of the posterior wall of the thoracic canal, for the decompression of severe thoracic myelopathy caused by tuberous ossification of the ligamentum flavum (OLF).

SUMMARY OF BACKGROUND DATA

OLF has been widely recognized as a cause of thoracic myelopathy in East Asia. Surgical decompression of thoracic myelopathy caused by OLF is technically demanding. Although several surgical decompression procedures have been described, acute neurological deterioration is common.

MATERIALS AND METHODS

Eighteen patients with severe thoracic myelopathy caused by tuberous OLF underwent posterior decompression via segmental en bloc resection of the posterior wall of the thoracic canal. The ossified ligamentum flavum, laminae, and partial facet joints of each segment were resected en bloc. Ossified dura mater was removed if present. Posterior fixation with pedicle screws was followed by lateral bone graft fusion.

RESULTS

The mean preoperative modified Japanese Orthopaedic Association score (total score, 11) was 4.1 (range, 2-5). Postoperatively, no neurological deterioration occurred, and all patients improved clinically. With an average follow-up of 31.2 months (range, 24-42 mo), the average modified Japanese Orthopaedic Association score was 7.8 (range, 6-10), representing a 2- to 5-point improvement. The average improvement rate was 55.2% (range, 33.3%-83.3%). Most patients were functionally independent at the last follow-up. Forty ossified segments were resected. The average time required for the resection of 1 segment was 77 minutes. Intraoperatively, dural ossification was noted in 11 patients. Complete resection was performed in all patients. Cerebrospinal fluid leakage occurred in 5 patients.

CONCLUSION

Segmental en bloc resection of the posterior wall of the thoracic canal is a safe and effective alternative for OLF-related severe thoracic myelopathy.

Circumferential Decompression via a ModifiedCostotransversectomy Approach for the Treatment of Single Level Hard Herniated Disc between T10 -L1

OBJECTIVE

To describe a novel surgical strategy for circumferentially decompressing the T10 -L1 spinal canal when impinged upon by single level hard thoracic herniated disc (HTHD) via a modified costotransversectomy approach.

METHODS

This is a retrospective review of 26 patients (17 men, 9 women; mean age at surgery 48.5 years, range 20-77 years) who had undergone single level HTHD between T10 -L1 by circumferential decompression via a modified costotransversectomy approach. The characteristics of the approach are using a posterior midline covered incision, which keeps the paraspinal muscle intact and ensures direct visualization of circumferential spinal cord decompression of single level HTHD between T10 -L1 .

RESULTS

The average operative time was 208 ± 36 min (range, 154-300 min), mean blood loss 789 ± 361 mL (range, 300-2000 mL), mean preoperative and postoperative mJOA scores 5.2 ± 1.5 and 9.0 ± 1.3, respectively (t = 19.7, P < 0.05). The rate of recovery of neurological function ranged from 33.3% to 100%. The ASIA grade improved in 24 patients (92.3%) and stabilized (no grade change) in two (7.7%). MRI indicated that the cross-sectional area of the dural sac at the level of maximum compression increased from 45.0 ± 5.8 mm(2) preoperatively to 113.5 ± 6.1 mm(2) postoperatively (t = 68.2, P < 0.05). Anterior tibialis muscle strength of the 15 patients with foot drop had a mean recovery rate of 95% at final follow-up. One patient who resumed work early after the surgery showed a significantly augmented Cobb angle. One patient had transient postoperative cerebrospinal fluid leakage. No patients showed neurological deterioration.

CONCLUSIONS

This procedure achieves sufficient direct visualization for circumferential decompression of the spinal cord via a posterior midline covered costotransversectomy approach with friendly bleeding control and without muscle sacrifice. It is a reasonable alternative treatment option for thoracic myelopathy caused by single level HTHD between T10 -L1 .

Risk factors and outcomes in thoracic stenosis with myelopathy: A single center experience

OBJECTIVE

Identify risk factors predisposing to thoracic spinal stenosis and myelopathy (TS) and address treatment options and outcomes.

METHODS

A retrospective review of our center's experience with TS over 10 years. Clinical and magnetic resonance imaging (MRI) data, surgical intervention and outcomes using Frankel and Japanese Orthopedic Association (JOA) scales were collected.

RESULTS

A total of 44 patients with TS were identified. There were 30 men and 14 women with a mean age±SD of 66±15years. Neurological performance was evaluated using the Frankel scale (A-E or 1-5), and JOA scale for myelopathy (0-11). Frankel scores (1-5) and JOA scores (0-11) on admission were 3.5±0.9 and 6.8±2.6 respectively. At follow-up, Frankel scores had improved to 4.1±0.8 (p=0.041) and JOA scores had improved to 8.3±2.4 (p=0.021). The presence on admission of increased signal from the cord on T2-weighted MRI was associated with lower Frankel and JOA scores (3.3±0.9, and 6.2±2.5 respectively) than in those with absent increased signal (4.0±0.4 and 8.6±2.1, p=0.02 and p=0.008 respectively). There were 4 complications, requiring exploration and debridement for dehiscence in 3 and an epidural hematoma in the fourth that necessitated evacuation, with a good outcome. A fifth patient underwent reoperation at the same level 18 months later for persistent stenosis.

CONCLUSION

Thoracic stenosis with myelopathy should be entertained in patients with myelopathy. Over half of our patients with TS were over the age of 70, and men outnumbered women by a ratio of 2:1. Nearly half the patients with TS had concomitant cervical and/or lumbar degenerative disease warranting surgery also. Increased signal intensity on T2-weighted MRI images correlated with lower Frankel and JOA scores compared to those without. Decompression for thoracic stenosis is associated with neurological improvement.

The CT and intraoperative observation of pedicel-ossification tunnel in 151 cases of thoracic spinal stenosis from ossification of ligamentum flavum

PURPOSE

The aim of this study is to precisely illustrate the pedicle-ossification tunnel (POT)-a spinal cord-free pathway in upper facet joint en bloc resection, which was reported as a comparatively neurological safer decompression surgery for thoracic ossification of ligamentum flavum (OLF).

METHODS

From 1998 to 2009, 151 patients with thoracic spinal stenosis from OLF were diagnosed by CT, MRI, neurological examinations and confirmed by postoperative pathological examination. The existence and configuration of the POT were observed by interactive CT virtual endoscopic (CTVE) image with multiplanar reconstructions and confirmed by intraoperative observation. Posterior decompression by upper facet joint en bloc resection via POT was conducted in all patients and the advantage of surgery was evaluated by modified Japanese Orthopedic Association scores pre- and post-operatively.

RESULTS

Through CTVE and intraoperative observation, no spinal cord was found present in POTs. OLF bloc divided the foramen into three parts: upper POT, OLF bloc and lower POT. The POT was the epidural space between the lateral border of OLF and its neighboring pedicles inner cortex. The recovery rate of upper facet joint en bloc resection via POT was 75.24 ± 18.01 %.

CONCLUSIONS

POT is a spinal cord-free pathway between OLF bloc and its neighboring pedicles in thoracic spinal stenosis which can be applied in neuron preserved decompression surgery.

Foot drop caused by single-level disc protrusion between T10 and L1

STUDY DESIGN

Retrospective investigation of surgical treatment of 25 patients with foot drop from single-level disc protrusion in the region of T10 to L1.

OBJECTIVE

To describe cases of foot drop from single-level disc protrusion in the region of T10 to L1 and surgical outcomes.

SUMMARY OF BACKGROUND DATA

Three cases of foot drop from T12-L1 disc protrusion are reported in the literature. Little is known, however, about foot drop resulting from single-level disc protrusion between T10 and L1 or its surgical outcomes.

METHODS

Between January 1995 and October 2010, a total of 25 patients (mean age: 44 yr; range, 21-68 yr) presented to our department with single-level disc protrusion between T10 and L1 (6 at T10-T11, 7 at T11-T12, and 12 at T12-L1) with associated foot drop and without cervical or lumbar spinal stenosis or other neurological disease. The average follow-up period was 46.5 months. We treated all cases surgically with circumferential decompression with fixation. We assessed neurological status, tibialis anterior muscle strength, magnitude of local kyphosis, and cross-sectional area at the level of compression of the dural sac preoperatively and at the final follow-up.

RESULTS

Preoperatively, all 25 patients exhibited both foot drop resulting from a lower motor neuron lesion and pathological reflexes resulting from an upper motor neuron lesion. Postoperatively, the mean calculated muscle strength recovery rate was 95%. Mean Japanese Orthopaedic Association score increased from 5.92 ± 1.22 points preoperatively to 9.56 ± 0.92 points at the final follow-up. Magnetic resonance imaging indicated that the cross-sectional area increased from 36.3 ± 7.3 mm2 preoperatively to 133.1 ± 6.1 mm2 postoperatively.

CONCLUSION

Foot drop can be caused by single-level disc protrusion between T10 and L1 and is usually associated with an upper motor neuron lesion. Pathological reflexes resulting from disc protrusion occurring between T10 and L1 differ depending on the level of the protrusion. Circumferential decompression with fixation may be an effective treatment option for this syndrome.

LEVEL OF EVIDENCE

4.