This report demonstrates the preoperative workup, surgical planning, and execution for performing 2-level posterior endoscopic foraminotomy. Unilateral radiating arm pain, resulting from degenerative changes in the cervical spine, typically stems from lateral disc herniations or osteophytes within the intervertebral foramen. Posterior endoscopic cervical foraminotomy is a minimally invasive surgical technique to decompress the cervical nerve root without sacrificing a motion segment. A 42-year-old male patient with C6 and C7 radiculopathy experienced insufficient pain relief in response to nonoperative therapy. Radiological imaging demonstrated a neuroforaminal nerve compression at the left side of the C6 and C7 levels. Two-level single-incision posterior cervical endoscopic foraminotomy was performed. In this detailed demonstration of the case, the reader will learn the surgical technique and anatomical considerations to safely perform this cervical endoscopic procedure.

To demonstrate the preoperative workup, surgical planning and execution of transforaminal endoscopic thoracic discectomy (TETD) for a giant calcified disc herniation. Surgeries for symptomatic thoracic disc herniations are rare and challenging. The main goal is to achieve sufficient decompression with minimal manipulation of the spinal cord. Conventional surgical techniques may have significant approach-related morbidities and often require additional stabilization. The full endoscopic transforaminal technique is the least invasive approach so far. A 73-year-old female patient with progressive gait disturbance and paraparesis received radiological imaging which revealed a giant calcified thoracic disc herniation at the level T11–12. The preoperative workup, planning and execution of TETD is demonstrated in detail. This report represents a typical educational case of a giant calcified thoracic disc herniation, treated by TETD.

This video aims to describe an endoscopic surgical approach for accessing difficult to reach pathology such as disc herniations after previous surgery. The relatively small size of endoscopic instruments facilitates significant freedom of movement inside the spinal canal. The authors have experience with interlaminar approaches for contralateral pathology such as disc herniations, recurrent disc herniations, spinal stenosis, and facet cysts. The advantages of starting from the opposite side of the canal in a revision situation include the ability to establish a clear plane between the dura and the borders of the canal and visualize the disc from a different angle than the index operation. Contralateral approaches to residual or recurrent herniations can be performed with an “over the top” technique, navigating dorsal to the thecal sac to reach the far side of the canal. In the associated video we demonstrate a novel technique, a contralateral transaxillary endoscopic approach to a recurrent disc herniation at the L5–S1 level in a young male collegiate wrestler. In our experience, we have found this particular approach to be useful in patients with an early take off of the S1 nerve root which creates a large axillary window. In several instances this technique has allowed us to inspect the area of the reherniation from both the axilla and over the top of the thecal sac. This particular patient has a large recurrence 2 years after an open microscopic hemilaminotomy and discectomy. In this instance, an approach was chosen that navigates dorsal to the S1 nerve root and ventral to the thecal sac, starting on the opposite side of the spinal canal from the herniation. This approach is described as a contralateral interlaminar transaxillary discectomy.

Objective: Endoscopic spine surgery is an emerging technique of minimally invasive spine surgery. However, headache, seizure, and autonomic dysreflexia are possible irrigation-related complications following full-endoscopic lumbar discectomy (FELD). Pressure elevation through fluid irrigation may contribute to these adverse events. A validated experimental model to investigate parameters for guideline definition is lacking. This study aimed to create an experimental setting for FELD with pressure assessments to prove the concept of repeatable and sensitive measurement of intracranial, intra- and epidural pressures during spine endoscopy. Methods: To measure intradural pressure, catheters were introduced through a sacral approach and advanced to lumbar, thoracic, and cervical levels in human cadavers. Similarly, lumbar epidural and intracranial probes were placed. The dural sac was filled with Ringer solution to a physiologic pressure of 15 cmH2O. Lumbar endoscopy was performed on 3 human cadavers at the L3–4 level. Pressure changes were measured continuously at all sites and the effects of backflow-occlusion were monitored. Results: Reproducibility of the experimental model was validated with catheters at the correct locations and stable compartmental pressure baselines at all levels for 3 specimens (mean±standard deviation: 1.3±2.9 mmHg, 9.0±2.0 mmHg, 6.0±1.2 mmHg, respectively). Pressure increase could be detected sensitively by closing the system with backflow-occlusion. Conclusion An experimental setup for feasible, repeatable, and precise pressure measurement during FELD in a human cadaveric setup has been developed. This allows investigation of the effects of endoscopic techniques and pump pressures on intra-, epidural and intracranial pressure and enables ranges of safe pump pressures per clinical situations.

To demonstrate the preoperative workup, surgical planning and execution of transforaminal endoscopic thoracic discectomy (TETD) for a giant calcified disc herniation. Surgeries for symptomatic thoracic disc herniations are rare and challenging. The main goal is to achieve sufficient decompression with minimal manipulation of the spinal cord. Conventional surgical techniques may have significant approach-related morbidities and often require additional stabilization. The full endoscopic transforaminal technique is the least invasive approach so far. A 73-year-old female patient with progressive gait disturbance and paraparesis received radiological imaging which revealed a giant calcified thoracic disc herniation at the level T11–12. The preoperative workup, planning and execution of TETD is demonstrated in detail. This report represents a typical educational case of a giant calcified thoracic disc herniation, treated by TETD.

This video aims to describe an endoscopic surgical approach for accessing difficult to reach pathology such as disc herniations after previous surgery. The relatively small size of endoscopic instruments facilitates significant freedom of movement inside the spinal canal. The authors have experience with interlaminar approaches for contralateral pathology such as disc herniations, recurrent disc herniations, spinal stenosis, and facet cysts. The advantages of starting from the opposite side of the canal in a revision situation include the ability to establish a clear plane between the dura and the borders of the canal and visualize the disc from a different angle than the index operation. Contralateral approaches to residual or recurrent herniations can be performed with an “over the top” technique, navigating dorsal to the thecal sac to reach the far side of the canal. In the associated video we demonstrate a novel technique, a contralateral transaxillary endoscopic approach to a recurrent disc herniation at the L5–S1 level in a young male collegiate wrestler. In our experience, we have found this particular approach to be useful in patients with an early take off of the S1 nerve root which creates a large axillary window. In several instances this technique has allowed us to inspect the area of the reherniation from both the axilla and over the top of the thecal sac. This particular patient has a large recurrence 2 years after an open microscopic hemilaminotomy and discectomy. In this instance, an approach was chosen that navigates dorsal to the S1 nerve root and ventral to the thecal sac, starting on the opposite side of the spinal canal from the herniation. This approach is described as a contralateral interlaminar transaxillary discectomy.

Objective: Endoscopic spine surgery is an emerging technique of minimally invasive spine surgery. However, headache, seizure, and autonomic dysreflexia are possible irrigation-related complications following full-endoscopic lumbar discectomy (FELD). Pressure elevation through fluid irrigation may contribute to these adverse events. A validated experimental model to investigate parameters for guideline definition is lacking. This study aimed to create an experimental setting for FELD with pressure assessments to prove the concept of repeatable and sensitive measurement of intracranial, intra- and epidural pressures during spine endoscopy. Methods: To measure intradural pressure, catheters were introduced through a sacral approach and advanced to lumbar, thoracic, and cervical levels in human cadavers. Similarly, lumbar epidural and intracranial probes were placed. The dural sac was filled with Ringer solution to a physiologic pressure of 15 cmH2O. Lumbar endoscopy was performed on 3 human cadavers at the L3–4 level. Pressure changes were measured continuously at all sites and the effects of backflow-occlusion were monitored. Results: Reproducibility of the experimental model was validated with catheters at the correct locations and stable compartmental pressure baselines at all levels for 3 specimens (mean±standard deviation: 1.3±2.9 mmHg, 9.0±2.0 mmHg, 6.0±1.2 mmHg, respectively). Pressure increase could be detected sensitively by closing the system with backflow-occlusion. Conclusion An experimental setup for feasible, repeatable, and precise pressure measurement during FELD in a human cadaveric setup has been developed. This allows investigation of the effects of endoscopic techniques and pump pressures on intra-, epidural and intracranial pressure and enables ranges of safe pump pressures per clinical situations.

To demonstrate the preoperative workup, surgical planning and execution of transforaminal endoscopic thoracic discectomy (TETD) for a giant calcified disc herniation. Surgeries for symptomatic thoracic disc herniations are rare and challenging. The main goal is to achieve sufficient decompression with minimal manipulation of the spinal cord. Conventional surgical techniques may have significant approach-related morbidities and often require additional stabilization. The full endoscopic transforaminal technique is the least invasive approach so far. A 73-year-old female patient with progressive gait disturbance and paraparesis received radiological imaging which revealed a giant calcified thoracic disc herniation at the level T11–12. The preoperative workup, planning and execution of TETD is demonstrated in detail. This report represents a typical educational case of a giant calcified thoracic disc herniation, treated by TETD.

This video aims to describe an endoscopic surgical approach for accessing difficult to reach pathology such as disc herniations after previous surgery. The relatively small size of endoscopic instruments facilitates significant freedom of movement inside the spinal canal. The authors have experience with interlaminar approaches for contralateral pathology such as disc herniations, recurrent disc herniations, spinal stenosis, and facet cysts. The advantages of starting from the opposite side of the canal in a revision situation include the ability to establish a clear plane between the dura and the borders of the canal and visualize the disc from a different angle than the index operation. Contralateral approaches to residual or recurrent herniations can be performed with an “over the top” technique, navigating dorsal to the thecal sac to reach the far side of the canal. In the associated video we demonstrate a novel technique, a contralateral transaxillary endoscopic approach to a recurrent disc herniation at the L5–S1 level in a young male collegiate wrestler. In our experience, we have found this particular approach to be useful in patients with an early take off of the S1 nerve root which creates a large axillary window. In several instances this technique has allowed us to inspect the area of the reherniation from both the axilla and over the top of the thecal sac. This particular patient has a large recurrence 2 years after an open microscopic hemilaminotomy and discectomy. In this instance, an approach was chosen that navigates dorsal to the S1 nerve root and ventral to the thecal sac, starting on the opposite side of the spinal canal from the herniation. This approach is described as a contralateral interlaminar transaxillary discectomy.

Objective: Endoscopic spine surgery is an emerging technique of minimally invasive spine surgery. However, headache, seizure, and autonomic dysreflexia are possible irrigation-related complications following full-endoscopic lumbar discectomy (FELD). Pressure elevation through fluid irrigation may contribute to these adverse events. A validated experimental model to investigate parameters for guideline definition is lacking. This study aimed to create an experimental setting for FELD with pressure assessments to prove the concept of repeatable and sensitive measurement of intracranial, intra- and epidural pressures during spine endoscopy. Methods: To measure intradural pressure, catheters were introduced through a sacral approach and advanced to lumbar, thoracic, and cervical levels in human cadavers. Similarly, lumbar epidural and intracranial probes were placed. The dural sac was filled with Ringer solution to a physiologic pressure of 15 cmH2O. Lumbar endoscopy was performed on 3 human cadavers at the L3–4 level. Pressure changes were measured continuously at all sites and the effects of backflow-occlusion were monitored. Results: Reproducibility of the experimental model was validated with catheters at the correct locations and stable compartmental pressure baselines at all levels for 3 specimens (mean±standard deviation: 1.3±2.9 mmHg, 9.0±2.0 mmHg, 6.0±1.2 mmHg, respectively). Pressure increase could be detected sensitively by closing the system with backflow-occlusion. Conclusion An experimental setup for feasible, repeatable, and precise pressure measurement during FELD in a human cadaveric setup has been developed. This allows investigation of the effects of endoscopic techniques and pump pressures on intra-, epidural and intracranial pressure and enables ranges of safe pump pressures per clinical situations.