Paravertebral Muscle Morphology in L4-L5 Disc Herniation: Insights from the Michigan State University Classification.

BACKGROUND Lumbar disc herniation (LDH) at L4-L5 impacts paravertebral muscle morphology. Intervertebral disc degeneration is linked to paravertebral muscle changes, affecting LDH treatment outcomes. This study explored L4-L5 LDH paravertebral muscle alterations, specifically in the erector spinae, multifidus, and psoas major, using Michigan State University's classification to guide LDH treatment. MATERIAL AND METHODS The study enrolled 160 patients, including 39 normal patients and 121 L4-L5 LDH patients. Patients with LDH were grouped according to MSU classification and compared to the normal group according to demographics and imaging changes. RESULTS In patients with L4-L5 herniation in Zone B, the FI of the ES muscle at L3-L4 level, L4-L5 level, and L5-S1 level was higher than that of normal people (P=0.018, P=0.043, P=0.010, respectively), and there was no difference between FI of MF and normal people. The Zone B patients also had a smaller CSA of the ES muscle at L4-L5 level than that in the normal group (P=0.049). Patients in the Zone C group were older than those in the normal group (P=0.014). The CSA of the PM of patients with Grade 3 herniation differed from that of the normal group at the L4-L5 and L5-S1 level. They were higher than in normal people at L4-L5 level (P=0.011) and lower at L5-S1 level (P=0.028). CONCLUSIONS In patients with L4-L5 herniation in Zone B, the FI of ES at L3-S1 level was higher than in normal people, and the CSA at L4-L5 level was smaller than in normal people. In patients with Grade3 herniation, PM CSA was larger at L4-L5 level and smaller at L5-S1 level than in normal people.

Highly Diastereoselective Synthesis of Oxindoles Containing Vicinal Quaternary and Tertiary Stereocenters by a Domino Heck/Decarboxylative Alkynylation Sequence.

A palladium-catalyzed domino Heck/decarboxylative alkynylation reaction of trisubstituted alkenes or enamines is reported. For two different types of substrates, the current domino reaction employing different solvents and bases led to 3,3-disubstituted oxindoles and hydropyrimidinyl spirooxindoles containing vicinal quaternary and tertiary stereocenters in moderate to good yields, respectively. The general applicability of this method was shown by gram-scale syntheses and diverse transformations of the reaction products. The enantioselective version for this domino process was also studied.

Repair of Delayed Meningeal Cyst after Spinal Surgery with Paraspinal Muscle Flap under Microscope.

BACKGROUND: Delayed meningeal cyst (DMC) is a rare complication after spinal surgery that is often ignored by clinicians, and its in-depth research is infrequent. In particular, no consensus has been reached about its surgical treatment. We found that patients with a DMC failed after conservative treatment, epidural blood patch, subarachnoid drainage, and initial attempts to eliminate the meningeal cyst. Therefore, we introduce the application of a paraspinal muscle flap repair under a microscope for the treatment of DMC. METHODS: In this study, 13 patients who were repaired by a paraspinal muscle flap under a microscope for DMC from January 2007 to January 2017 were retrospectively reviewed. Their ages were 18-68 years old (mean age 48.7 years). The course of the disease ranged from 3 weeks to 28 months after the operation for the primary disease, with an average of 10.6 months. Length >5 cm was called a large DMC and length >8 was called a giant DMC. By analyzing the effect of surgical treatment, we summarized the treatment experience of DMC and evaluated the risk factors for the formation of DMC. RESULTS: All patients were treated with paraspinal muscle flap repair under a microscope, and they healed well after the operation. There was no cerebrospinal fluid leakage or other operation-related complication. The mean follow-up was 16.5 months. Reexamination of the spine MRI showed no recurrence of the DMC. CONCLUSIONS: The application of paraspinal muscle flap under a microscope combined with glue, bedrest, and CSF drain, was an effective option for the patients with DMC.

Precise Surgical Treatment of Thoracic Ossification of Ligamentum Flavum Assisted by O-Arm Computer Navigation: A Retrospective Study.

OBJECTIVE: O-arm computer navigation-assisted technology (OACNAT) has been widely used in the treatment of thoracic ossification of ligamentum flavum (TOLF) in recent years, but there are few in-depth studies on the safety and effectiveness of this approach. The purpose of this study was to investigate the clinical effect of accurate surgical treatment for TOLF with OACNAT. METHODS: From January 2010 to January 2018, the clinical data of 64 patients with TOLF who underwent laminectomy and internal fixation in the Third Hospital of Hebei Medical University were retrospectively reviewed. The patients were divided into group A (with OACNAT, n = 33) and group B (without OACNAT, n = 31) according to the application of OACNAT during the operation. The possible operation-related variables, imaging results, and clinical effects were compared between the 2 groups. RESULTS: In terms of demographics, there were no significant differences between group A and group B in age, sex, body mass index, smoking, drinking, heart disease, hypertension and diabetes (P > 0.05). In terms of operation-related variables, imaging results, and clinical efficacy, there were significant differences in operation time, wound length, postoperative modified Japanese Orthopaedic Association (JOA) score, JOA score improvement rate, accuracy of screw placement, number of intraoperative fluoroscopy procedures, and cerebrospinal fluid leakage between group A and group B (P < 0.05). There were no significant differences in other variables between the 2 groups (P > 0.05). In contrast to group A, in group B, 2 patients had incorrect segmental localization, 3 patients had residual ossified ligamentum flavum after the operation, and 1 patient had postoperative neurologic impairment. On further analysis, compared with group B, group A had a shorter operation time, more accurate screw placement, fewer fluoroscopy procedures, higher JOA score improvement rate, and lower incidence of complications. CONCLUSIONS: The use of OACNAT accurately located the position, size, shape, and boundary of ossification of the ligamentum flavum during the operation, which could guide accurate decompression and improve the accuracy of pedicle screw placement. This approach not only reduced the incidence of incorrect segmental localization and incomplete or excessive decompression but also reduced the risk of related complications and improved the accuracy, safety, and effectiveness of the operation.