Microsurgical resection of ossification of the posterior longitudinal ligament in the thoracic spine via the transthoracic approach without spinal fusion: case series and technical note

The Transaxillary Approach as a Direct Route in the Management of Upper Thoracic Spine Pathology: A Technical Note with Case Series

This retrospective case series of prospective data aims to describe the transaxillary approach for the treatment of upper thoracic spine pathology. Various surgical techniques and approaches have been reported across the literature to address upper thoracic spine pathology, including the cervicothoracic approach, anterior transsternal approach, posterolateral approach, supraclavicular approach, and lateral parascapular approaches. These techniques are invasive. A minimally invasive, less morbid, and direct access approach to the pathology of the upper thoracic spine has not been reported in the literature. Patients with pathology affecting the first thoracic vertebra up to the sixth thoracic vertebra were classified into the upper thoracic spine group. Patients with pathology below the sixth thoracic vertebra were excluded. Patients not having a minimum follow-up of 12 months were also excluded. The study analyzed 18 patients. The mean preoperative modified Japanese Orthopedic Association score was 7.2±1.44, which improved to 10.16±1.2 (p<0.05). The majority (14/18) of the patients had an excellent outcome. Three patients had good outcomes, and one patient had a fair outcome. Five cases of intraoperative dural leak were recorded, and one patient had postoperative neurological deficit. The transaxillary approach is a safe, viable, muscle-sparing, and minimally invasive approach for ventral pathologies of the upper thoracic spine.

Anterior shift of the ventral dura mater: A novel concept of the posterior surgery for ossification of the posterior longitudinal ligament in thoracic spine

Background

Thoracic myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) remains one of the most difficult disorders to treat. The Ohtsuka procedure, extirpation, or anterior floating of the OPLL through a posterior approach, has shown great surgical outcomes after several modifications. However, these procedures are technically demanding and pose a significant risk of neurological deterioration. We have developed a novel modified Ohtsuka procedure in which removal or minimization of the OPLL mass is unnecessary; instead, the ventral dura mater is shifted anteriorly with the posterior part of the vertebral bodies and targeted OPLL.

Surgical Procedure

First, pedicle screws were inserted at more than three spinal levels above and below the spinal level where pediculectomies were performed. After laminectomies and total pediculectomies, partial osteotomy of the posterior vertebra adjacent to the targeted OPLL was performed by using a curved air drill. Then, the PLL is completely resected at the cranial and caudal sites of the OPLL using special rongeurs or a threadwire saw with a diameter of 0.36 mm. The nerve roots were not resected during surgery.

Methods

Eighteen patients (follow-up ≥1 year) treated with our modified Ohtsuka procedure were assessed clinically, including the Japanese Orthopaedic Association (JOA) score for thoracic myelopathy and radiographically.

Results

The average follow-up period was 3.2 years (range, 1.3-6.1 years). The preoperative JOA score was 2.7 ± 1.7, which improved to 8.2 ± 1.8 at 1 year postoperatively; therefore, the recovery rate was 65.8 ± 19.8%. The CT scan at 1 year after surgery revealed the anterior shift of the OPLL averaged 3.1 ± 1.7 mm and the ossification-kyphosis angle of the anterior decompression site decreased at an average of 7.2 ± 6.8 degrees. Three patients demonstrated temporary neurological deterioration, all of whom completely recovered within 4 weeks postoperatively.

Discussion

The concept of our modified Ohtsuka procedure is 1) not OPLL extirpation or minimization but only the creation of space between the OPLL and spinal cord by an anterior shift of the ventral dura mater, which is achieved by complete resection of the PLL at the cranial and caudal sites of the OPLL; and 2) no nerve roots are sacrificed to prevent ischemic spinal cord injury. This procedure is not technically demanding and safe and provides secure decompression for thoracic OPLL. The anterior shift of the OPLL was smaller than expected, but it resulted in a relatively good surgical outcome with a recovery rate ≥65%.

Conclusion

Our modified Ohtsuka procedure is quite secure and is not technically demanding, with a recovery rate of 65.8%.

Comparison of perioperative complications in anterior decompression with fusion and posterior decompression with fusion for thoracic ossification of the posterior longitudinal ligament -a retrospective cohort study using a nationwide inpatient database

BACKGROUND

Thoracic ossification of the posterior longitudinal ligament (T-OPLL) is a rare disease, which can cause spinal cord compression leading to various neurological symptoms. There are limited treatment options for T-OPLL, surgery is generally considered the only effective treatment. However, few studies have investigated surgical complications in patients with T-OPLL, and there are no data regarding surgical risks in anterior decompression with fusion (ADF) when compared with posterior decompression with fusion (PDF) for T-OPLL.

METHODS

Patients who were diagnosed as T-OPLL and underwent ADF via the anterior approach and PDF via the posterior approach from April 1, 2012 to March 31, 2018, were extracted from the Diagnosis Procedure Combination (DPC) database. We analyzed perioperative systemic and local complication rates after ADF and PDF and compared them using propensity score matching (PSM) method. In each of the two groups, we investigated the details of length of stay, costs, mortality, and discharge destination.

RESULTS

In total 1344 patients (ADF: 88 patients, PDF: 1256 patients), 176 patients were investigated after PSM (88 pairs). While the incidence of overall systemic complication was significantly higher in the ADF group (ADF/PDF: 25.0%/8.0%, P = 0.002), there was no significant difference in the overall local complication rate (15.9%/19.3%, P = 0.55). Specifically, respiratory complications were more frequently observed in the ADF group (9.1%/0%, P = 0.004), however, other systemic and local complications did not differ significantly between the two groups. The length of stay was 1.7 times longer (P < 0.001) and the medical costs were 1.4 times higher (P < 0.001) in patients with perioperative complications, compared to those without perioperative complications.

CONCLUSION

We demonstrated the perioperative complications of ADF and PDF in patients with T-OPLL using a large national database. ADF showed a higher incidence of respiratory complications. Development of perioperative complications was associated with longer hospital stay and higher medical costs.

Novel Simultaneous Decompression Through Single-stage Mini-thoracotomy for Concurrent Ossification of the Posterior Longitudinal Ligament and Ossification of the Ligamentum Flavum at the Same Thoracic Level: A Technical Report and Literature Review

STUDY DESIGN

Technical case report.

OBJECTIVE

To describe a novel technique of decompression through single-stage mini-thoracotomy for removing concurrent ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF) at the same thoracic level simultaneously.

SUMMARY OF BACKGROUND DATA

Concurrent OPLL and OLF at the same thoracic level is not common. Because these conditions lead to severe thoracic myelopathy, however, they require surgical decompression.To date, several cases with concurrent OPLL and OLF at the same thoracic level and surgical methods to treat these conditions have been described. However, no consensus on the surgical methods for the treatment these conditions has been established and these surgical methods have been also reported to be linked with the incidence of complication like neurological deterioration and the requirement of bone grafting and instrumentation.

METHODS

Three consecutive patients who presented with thoracic myelopathy caused by concurrent OPLL and OLF at the same thoracic level were treated by our novel surgical technique of decompression through single-stage mini-thoracotomy.

RESULTS

Simultaneous complete removal of OPLL and OLF through single-stage mini-thoracotomy was performed successfully in the three patients. All patients' preoperative symptoms gradually improved during the follow-up period, and no additional complications were associated with removal of OLF through thoracotomy. And there was no kyphotic change or instability in the thoracic spine after more than a year of follow-up although both bone grafting and instrumentation were not performed.

CONCLUSION

This novel surgical technique is considered to be able to be a safe and effective alternative to the conventional treatment of selective cases of thoracic myelopathy caused by concurrent OPLL and OLF at the same thoracic level.Level of Evidence: 4.

Transthoracic microsurgical anterior decompression without fusion for ossification of the posterior longitudinal ligament in the thoracic spine

OBJECTIVE

The authors aimed to analyze outcomes following transthoracic microsurgical anterior decompression of thoracic ossification of the posterior longitudinal ligament (T-OPLL), which was causing myelopathy, and determine the predictive factors for surgical outcomes.

METHODS

Patients who underwent transthoracic microsurgical anterior decompression without fusion for the treatment of T-OPLL from December 2014 to May 2019 were included. Demographic, radiological, and perioperative data and clinical outcomes of 35 patients were analyzed. The modified Japanese Orthopaedic Association (mJOA) score and recovery rate were used to evaluate functional outcomes.

RESULTS

A total of 35 consecutive patients (8 men and 27 women; mean age 52.2 ± 10.8 years) were enrolled in this study, and the mean follow-up period was 65.5 ± 51.9 months. The mean mJOA score significantly improved after surgery (5.9 ± 1.8 vs 8.3 ± 1.5, p < 0.001), with a mean recovery rate of 47.7% ± 24.5%. The visual analog scale (VAS) score significantly improved after surgery (7.3 ± 1.3 vs 4.3 ± 0.7, p < 0.001). The outcome was excellent in 4 patients (11.4%), good in 21 patients (60.0%), fair in 4 patients (11.4%), unchanged in 5 patients (14.3%), and worsened in 1 patient (2.9%). There were 12 cases of CSF leakage, 1 case of epidural hematoma, 1 case of pleural effusion, and 1 case of pneumothorax. Age, preoperative kyphotic angle, anteroposterior length of T-OPLL at the maximally affected level, and mass occupying rate were identified as predictors associated with postoperative outcome. A multivariate regression analysis revealed that age and preoperative kyphotic angle were independent risk factors for postoperative outcomes.

CONCLUSIONS

Transthoracic microsurgical anterior decompression without fusion achieved favorable clinical and radiological outcomes for treating T-OPLL with myelopathy. Patient age and preoperative kyphotic angle were independent risk factors for lower recovery rate.