Thoracic spinal stenosis (TSS) is a general term for the compression of the thoracic spinal cord due to multiple causes. OLF (Ossified Ligamentum Flavum), TDH (Thoracic Disc Herniation) and OPLL (Ossified Posterior Longitudinal Ligament) are the three main causes of thoracic spinal stenosis, and these causes often coexist. Once thoracic spinal stenosis occurs, conservative treatment is often ineffective, and surgery is still considered the only, effective treatment for the disease. Due to the anatomical characteristics of the thoracic spine, especially for the upper and middle thoracic spine, it is very important to accurately locate and mark the surgical segment before surgery. For posterior surgery, our current marking method is still preoperative injection of methylene blue staining into the thoracic spinous process of the operated segment under X-ray or CT positioning, but this method should not inject methylene blue too deeply into the intervertebral plate or even into the spinal canal, because once methylene blue is injected into the dural surface, it may lead to a serious inflammatory reaction in the spinal canal, and furthermore, the dose of injection should be as small as possible to prevent too large a diffusion area, which may lead to difficulty in localizing the segment. Sammon et al. reported the placement of an elastic coil within the soft tissue of the surgical segmental pedicle surface under preoperative CT localization, which was first used for localization and marking of breast cancer lesions, and reported that this method was simple and accurate. For anterior surgery of TDH, it is still difficult to accurately locate and mark the surgical segment. Some scholars reported that preoperative CT-guided injection of contrast agent or elastic coil into the vertebral body or arch root of the surgical segment is accurate, but it is somewhat invasive, and the effectiveness and safety of this method have yet to be further evaluated clinically. OLF is the most common cause of thoracic spinal stenosis, accounting for approximately 80% of its prevalence. oLF occurs in the middle and lower thoracic spine, and the excessive tension stimulation of the ligamentum flavum by long-term and repeated activities of the thoracic synovial joints may be one of the main mechanisms of OLF pathogenesis. Posterior laminectomy and decompression is still the most common surgical method for the treatment of OLF, but direct use of laminectomy occlusion forceps should not be used to reduce the stimulation of the compressed spinal cord. The “uncovered” laminectomy of the lamina and ligamentum flavum via the articular eminence or “posterior lamina grinding” is the most commonly used procedure. In addition, it has been reported that a “root-yellow channel” can be used to safely remove the entirety of the superior articular eminence and OLF. The author has modified the posterior decompression of the spinal canal and reported the use of “total laminectomy and reimplantation of the enlarged spinal canal” for the treatment of OLF, in which a swing saw and a thin osteotome were used to remove the entire lamina and OLF, and then the ossified ligamentum flavum was removed and then reimplanted in situ, thus restoring the posterior muscle attachment point and at the same time The combination of OLF with dural calcification and adhesions is not uncommon and is relatively difficult to manage, with high surgical risk and a high incidence of postoperative cerebrospinal fluid leakage. The two characteristic features are the “double track sign” and the “comma sign”. The surgical options are either dural wall resection with dural repair or dural floatation of the calcified dura. After removal of the entire calcified dura, a dural repair is often recommended. “The “floating dura” method refers to the preservation of the thin layer of calcified dura attached to the dura during surgery. This may be related to epidural pulsation and pressure in the epidural plexus, and posterior fixation and fusion may facilitate atrophy of the calcified dura after “floating,” but it is controversial whether this procedure can achieve immediate and complete decompression of the spinal canal. Extensive decompression of the lamina in multisegment OLF is recommended along with posterior fixation and fusion. Overall, the prognosis for OLF is relatively good compared with surgery for other causes of thoracic spinal stenosis, but the overall remission rate is still only about 50%, and the severity of the preoperative disease, as well as the duration and surgical technique, have an important impact on the prognosis. TDH accounts for approximately 15% of the incidence of thoracic spinal stenosis and occurs in men aged 40-50 years, mostly with single-segment onset. Due to the mobility of the thoracic spine and the strength of the posterior longitudinal ligament, TDH also occurs in the middle and lower thoracic spine, especially in the T11/T12 segment, and is mostly of the central or paracentral type. When TDH is combined with spinal cord compression symptoms, intractable back pain or radicular pain, surgery is required, and there are many surgical approaches to TDH, including transthoracic (transthoracic, transthoracic, posterior pleural), postero-lateral transverse cribriform approach, postero-lateral transforaminal approach, and transforaminal – preserved transforaminal approach. The choice of approach depends on the location of the TDH, its size, the presence or absence of calcification, the presence or absence of other co-morbidities (e.g., OLF or OPLL), and the surgeon’s familiarity with the approach. Regardless of the approach chosen, the central principle of surgery is to remove the compressed disc with minimal disturbance to the already compressed spinal cord. For paracentral or posterolateral discs, the posterior-lateral approach is the preferred option. In the case of central TDH, the thoracoscopic or open anterolateral approach, the transverse costal approach, and the juxta-articular approach are relatively safe in order to reduce the stimulation of the compressed spinal cord. Although thoracoscopic surgery is relatively less traumatic, it has a steep term curve, high equipment requirements and narrow indications, which are not suitable for clinical promotion; traditional open thoracic surgery is more traumatic and not suitable for lesions above the T4 segment, and with the wide application of minimally invasive working channel and XLIF technology, traditional open thoracic surgery is gradually being replaced by transthoracic surgery under minimally invasive working channel. In addition, in recent years, some scholars tend to choose the lateral transthoracic approach, which is done through the lateral aspect of the transverse costal junction, pushing away the wall pleura, revealing the herniated disc from the lateral side of the vertebral body under direct vision, and completing the resection operation, which, compared with the transthoracic approach, does not require access to the pleural cavity and does not require routine placement of closed chest drainage after surgery. Minimal Access Spinal Surgery (MASS), which further reduces surgical trauma, has a flat learning curve and is easy for spine surgeons to master and promote because it is performed under direct vision. The postero-lateral approach is also a common procedure for the treatment of central TDH, which involves a posterior median incision, resection of bilateral articular processes and transverse costal joints, partial resection of the adjacent pedicle if necessary, and pushing through the mural pleura along the lateral side of the vertebral body, allowing the disc to be removed at a smaller angle under the posterior incision to reduce the stimulation of the compressed spinal cord. The specific resection steps can be broadly divided into three steps: first, the residual disc is removed from the intervertebral space, then the herniated disc is separated from the posterior dural space and the herniated disc is pressed back into the intervertebral space, and then it is completely removed from the intervertebral space. The author has modified the posterior lateral approach by using a transarticular approach to remove the superior and inferior articular processes at the lesion gap without removing the ribs and stripping the pleura, and using the “eggshell technique” to complete the resection of TDH while preserving the spinous process and the vertebral plate, thus reducing the damage to spinal stability and pleural injury. For TDH with obvious calcification, huge or even protruding into the dural sac, surgical resection is more difficult, complications are relatively more frequent, and surgical results are relatively poor. Due to the adhesion of the calcified disc to the dural sac, surgical resection is likely to cause tearing of the dural sac, and repair is difficult, so some scholars suggest that the thin layer of disc tissue attached to the dura should be preserved as much as possible to prevent dural tearing. The incidence of multisegmental TDH is significantly lower than that of single-segment TDH, but treatment is more difficult. Although it has been suggested that differences in the level of pressure pain and sensory deficits in the lesioned segment as well as in the imaging presentation can be used as a basis for localization and thus for selective segmental surgery. However, the method of localizing the primary responsible segment for multisegmental TDH is still controversial, and for those who have difficulty in pinpointing the primary responsible segment, it is often necessary to treat multiple segments simultaneously. Moreover, after multi-segment TDH resection, posterior fixation and fusion are often recommended in order to prevent secondary thoracic lordosis or instability. The need for fusion after single-segment TDH is still controversial. At present, it is mostly believed that intervertebral fusion and fixation are necessary when there are more partial resections of adjacent vertebral bodies or when the diseased intervertebral disc is completely resected, resulting in intervertebral instability. OPLL is relatively uncommon in thoracic spinal stenosis, but it is the most difficult to manage. First, unlike OLF and TDH, OPLL in the thoracic spine occurs in the upper and middle thoracic spine, most commonly in the T3-4 segment, and surgery is recommended for OPLL once it causes symptoms of spinal cord compression; the choice of surgical approach for OPLL is related to the extent of the lesion, the presence or absence of combined OLF, and the angle of thoracic lordosis in the lesioned segment. For cervicothoracic OPLL, since the spinal curvature of this segment is still physiologically anterior or mildly retroconvex, posterior decompression of the vertebral plate is still the more commonly used surgical procedure. In the case of middle and lower thoracic OPLL, posterior plate decompression alone does not relieve spinal cord compression, but may lead to increased symptoms due to increased postoperative thoracic kyphosis and anterior displacement of the spinal cord. In recent years, for OPLL of the thoracic spine, especially when combined with OLF, the more commonly used procedure is 360-degree decompression of the thoracic spinal cord via the posterior approach, in which extensive laminectomy and decompression are performed first, followed by lateral and extrapleural access to the posterior lateral vertebral body to reveal and remove part of the vertebral body and intervertebral disc, and finally, using the cul-de-sac collapse method (similar to the eggshell technique), the resection of OPLL and anterior decompression of the spinal cord are completed from the lateral posterior side. It should be mentioned that after OPLL decompression of all thoracic spine segments, posterior fixation and fusion are emphasized at the same time, and proper “decompression” of the thoracic spine by internal fixation is beneficial to the posterior displacement of the spinal cord, thus helping to increase the decompression effect while preventing the progression of posterior convexity and ensuring the surgical efficacy. In conclusion, in recent years, with the progress of imaging, the continuous improvement of surgical techniques, surgical instruments and the popularity of intraoperative electrophysiological monitoring, the clinical diagnosis and treatment of thoracic spinal stenosis has been significantly improved. However, the surgical treatment of this disease is still considered one of the most challenging and risky procedures in spinal surgery. The surgeon’s mastery of the surgical strategy and the skill of the surgeon play a decisive role in the postoperative outcome of thoracic spinal stenosis. Therefore, in order to maximize surgical efficacy and prevent serious complications, surgical treatment of thoracic spinal stenosis must be carried out carefully and under adequate conditions.