A quantitative analysis of posterolateral approaches to the ventral thoracic spinal canal

Posterolateral approaches to the thoracic spine for calcific disc herniation: is wider exposure always better?

OBJECTIVE

To compare the costotransversectomy (CTV) and transpedicular (TP) approaches versus the transfacet (TF) approach for the surgical treatment of calcific thoracic spine herniations (cTDH), in terms of surgical and clinical outcomes.

BACKGROUND

Surgical approaches for cTDH are debated. Anterior approaches are recommended, while posterolateral approaches are preferred for non-calcific, paramedian, and lateral hernias. Currently, there is limited evidence about the superiority of a more invasive surgical approach, such as CTV or TP, over TF, a relatively less invasive approach, in terms of neurological outcome, pain, and surgical complications, for the treatment of cTDH.

METHODS

A retrospective, observational, monocentric study was conducted on patients who underwent posterolateral thoracic approaches for symptomatic cTDH, between 2010 and 2023, at our institute. Three groups were drafted, based on the surgical approach used: TF, TP, and CTV. All procedures were assisted by intraoperative CT scan, spinal neuronavigation, and intraoperative neuromonitoring. Analyzed factors include duration of surgery, amount of bone removal, intraoperative blood loss, CSF leak, need of instrumentation for iatrogenic instability, degree of disc herniation removal, myelopathy recovery. Afterwards, a statistical analysis was performed to investigate the bony resection of the superior posterior edge of the vertebral soma. The primary outcome was the partial or total herniation removal.

RESULTS

This study consecutively enrolled 65 patients who underwent posterolateral thoracic surgery for cTDH. The TF approach taking the least, and the CTV the longest time (p < 0.01). No statistical difference was observed between the three mentioned approaches, in terms of intraoperative blood loss, dural leakage, post-resection instrumentation, total herniation removal, or myelopathy recovery. An additional somatic bony resection was successful in achieving total herniation removal (p < 0.01), and the extent of bony resection was directly proportional to the extent of hernia removal (p < 0.01).

CONCLUSIONS

No statistically significant differences were highlighted between the TP, TF, and CTV regarding the extent of cTDH removal, the postoperative complications, and the neurological improvement. The described somatic bone resection achieved significant total herniation removal and was directly proportional to the preop against postop anteroposterior diameter difference.

Anatomical method for rib disconnection during posterior costotransversectomy for paravertebral access to the ventral thoracic spine

Posterior surgical approaches to the thoracic spine are commonly used for degenerative diseases, tumors, trauma, and other operative indications. A posterior approach for access to the paravertebral space is advantageous because it allows for resection of the vertebral body without violating the pleural cavity. Posterior costotransversectomy (PCT) is widely used for this purpose. It involves resection of the rib head after the ligamentous complexes have been disconnected from the transverse process and lateral vertebral body. The current literature provides only vague descriptions of the steps involved in rib disconnection with respect to PCT. A comprehensive knowledge of the anatomical relationships of the ligamentous and soft tissue complexes connecting the rib to the vertebral body is paramount for completing an efficient and safe surgery. This manuscript describes an anatomically directed method for rib disconnection during costotransvrersectomy.

Combined, Rib-Sparing, Bilateral Approach to the Ventral Mid and Low Thoracic Spine: Study on Comparative Anatomy and Surgical Feasibility

BACKGROUND

Pathologies of the ventral thoracic spine represent a challenge, igniting arguments about which should be the ideal surgical approach to access this area. Anterior transthoracic thoracotomy and a number of posterolateral routes have been developed. Among the latter, costotransversectomy has demonstrated to provide good ventral exposure with a lower, but not negligible, morbidity. The optimal approach should be the one minimizing surgical morbidity on both neural and extraneural structures while optimizing exposure.

METHODS

The authors described the combined, rib-sparing, bilateral approach (CRBA) to the ventral mid/low-thoracic spine. The technique combines a transfacet pedicle partially sparing approach on one side and a transpedicular with transverse process resection on the contralateral one. A laboratory investigation was conducted. The technique was applied in a surgical setting, and a case was reported.

RESULTS

CRBA is rib-sparing, completely extracavitary, and does not require pleural exposure and paraspinal muscle splitting, thus minimizing potential morbidity. The combination of 2 corridors ensures the greatest exposure compared with standard posterolateral approaches. The only blind corner is limited to a small area just in front of the dural sac. A bimanual approach optimizes control during surgical manipulation, even if the area of maneuverability and cross-section areas of surgical corridors are slightly limited compared to traditional costotransversectomy due to the minimally invasive nature of the procedure.

CONCLUSIONS

CRBA represents a safe and effective option to access the ventral mid/low thoracic spine. It provides great exposure and bimanual manipulation of the surgical target, minimizes potential morbidity, and avoids entrance into the thoracic cavity and paraspinal muscle splitting.

Trans-thoracic versus retropleural approach for symptomatic thoracic disc herniations: comparative analysis of 94 consecutive cases

PURPOSE

The authors illustrate their results in the surgical treatment of symptomatic thoracic disc herniations (TDHs) by comparing the traditional open to the less invasive retropleural lateral approaches.

METHODS

Retrospective review of 94 consecutive cases treated at a single Institution between 1988 and 2014. Fifty-two patients were males, 42 females, mean age was 53.9 years. Mean follow-up was 46.9 months (12-79 months). 33 patients were diagnosed with a giant thoracic disc herniation (GTDH). Upon admission, the most common symptoms were: motor impairment (91.4%, n = 86), neuropathic radicular pain with VAS > 4 (50%), bladder and bowel dysfunction (57.4% and 41.4% respectively) and sensory disturbances (29.7%). The surgical approach was based upon level, laterality and presence or absence of calcified lesions.

RESULTS

Decompression was performed in 7 cases via a thoraco-laparo-phrenotomy and in 87 cases via an antero-lateral thoracotomy. Out of the latter cases, 49 (56%) were trans-thoracic trans-pleural approaches (TTA) and 38 (44%) were less invasive retropleural approaches (MIRA). At follow-up, there were 59.5% neurologically intact patients according to the McCormick Scale, while 64.8% and 67% had no bladder or bowel dysfunction respectively. Complications occurred in 24 patients (25.5%). Pulmonary complications were the commonest (12.7%) with pleural effusion being significantly more common in patients treated with TTA compared to MIRA (20% vs 5.2%: X² 4.13 P:0.042). Severe post-operative neuralgia (VAS 7-10) was also significantly more frequent in the TTA group (22.4% vs 2.6% X² 7.07 p 0.0078).

CONCLUSIONS

MIRA is a safe and effective technique to obtain adequate TDH decompression and is associated with lower morbidity compared to TTA.