Ultrasonic spine surgery for every thoracic disc herniation: a 43-patient case series and technical note demonstrating safety and efficacy using a partial transpedicular thoracic discectomy with ultrasonic aspiration and ultrasound guidance

J Neurosurg Spine. 2021 Nov 19;36(5):800-808. doi: 10.3171/2021.8.SPINE21819. Print 2022 May 1.

Abstract

Objective: Thoracic disc herniations (TDHs) are a challenging pathology. A variety of surgical techniques have been used to achieve spinal cord decompression. This series elucidates the versatility, efficacy, and safety of the partial transpedicular approach with the use of intraoperative ultrasound and ultrasonic aspiration for resection of TDHs of various sizes, locations, and consistencies. This technique can be deployed to safely remove all TDHs.

Methods: A retrospective review was performed of patients who underwent a thoracic discectomy via the partial transpedicular approach between January 2014 and December 2020 by a single surgeon. Variables reviewed included demographics, perioperative imaging, and functional outcome scores.

Results: A total of 43 patients (53.5% female) underwent 54 discectomies. The most common presenting symptoms were myelopathy (86%), motor weakness (72%), and sensory deficit (65%) with a symptom duration of 10.4 ± 11.6 months. A total of 21 (38.9%) discs were fully calcified on imaging and 15 (27.8%) were partially calcified. A total of 36 (66.7%) were giant TDHs (> 40% canal compromise). The average operative time was 197.2 ± 77.1 minutes with an average blood loss of 238.8 ± 250 ml. Six patients required ICU stays. Hospital length of stay was 4.40 ± 3.4 days. Of patients with follow-up MRI, 38 of 40 (95%) disc levels demonstrated < 20% residual disc. Postoperative Frankel scores (> 3 months) were maintained or improved for all patients, with 28 (65.1%) patients having an increase of 1 grade or more on their Frankel score. Six (14%) patients required repeat surgery, 2 of which were due to reherniation, 2 were from adjacent-level herniation, and 2 others were from wound problems. Patients with calcified TDHs had similar improvement in Frankel grade compared to patients without calcified TDH. Additionally, improvement in intraoperative neuromonitoring was associated with a greater improvement in Frankel grade.

Conclusions: The authors demonstrate a minimally disruptive, posterior approach that uses intraoperative ultrasound and ultrasonic aspiration with excellent outcomes and a complication profile similar to or better than other reported case series. This posterior approach is a valuable complement to the spine surgeon's arsenal for the confident tackling of all TDHs.

Keywords: transpedicular thoracic discectomy; ultrasonic aspiration; ultrasound guidance.