Incidence and risk factors of heterotopic ossification after cervical Baguera C disc arthroplasty.

OBJECTIVE: This retrospective study was designed to evaluate the incidence and predisposing factors of heterotopic ossification (HO) after cervical disc arthroplasty (CDA) with a specific implant at 1 and 2 levels, and to investigate the biomechanical effects related to HO. The study goal was to identify ways to reduce the likelihood of HO formation after surgery. METHODS: The study included patients who underwent only 1- or 2-level CDA with the Baguera C disc between November 2014 and December 2021 at a single medical center. All patients were operated on by the same neurosurgeon. The surgical indication included 1-level or 2-level disc herniation between C3 and C7 with radiculopathy, myelopathy, or both, with minimal spondylosis. The various factors were assessed by evaluating plain radiographs and cervical CT scans. The presence of HO was evaluated at different intervals postsurgery, and HO severity was graded using the McAfee classification. RESULTS: Of 107 patients who underwent CDA, 47 (43.9%) had HO at 63 of 171 levels (36.8%). Most cases with HO were grade 1, and no grade 4 was observed. Statistically significant risk factors for HO were the length of endplate coverage ratio and inferior anterior residual exposed endplate (AREE); sex, age, implant height and width, shell angle, and pre- and postoperative functional spinal unit (FSU) angle were not significant. More AREE and greater kyphotic postoperative FSU angle in the flexion position were significant factors differentiating HO grades 0 and 1 from grades 2 and 3. Furthermore, the non-HO group showed a trend of higher range of motion at any postoperative time compared to the HO group, especially at 1 month after surgery. CONCLUSIONS: The HO incidence after CDA was correlated with the residual length of endplate coverage and inferior AREE. Additionally, the AREE and kyphotic postoperative FSU angle in the flexion position were associated with HO grade progression. Patients with HO also showed a trend of lower range of motion at 1 month after surgery. Using an adequately sized implant and encouraging neck motion may help prevent HO development and progression.

Cervical Conjoined Nerve Root During Posterior Percutaneous Endoscopic Cervical Diskectomy.

Cervical conjoined nerve root is rare, and medical imaging, such as magnetic resonance imaging and computed tomography, cannot give an accurate preoperative diagnosis.1 Treatment of cervical radiculopathy with root anomaly can be challenging. We report here a case of cervical conjoined nerve root with a 2-dimensional video. A 41-year-old woman without systemic disease presented with a 2-month history of neck and bilateral shoulder pain, upper back tightness, and left upper limb painful numbness, especially of the first to third fingers. The visual analog scale scores of the neck and left upper limb were 4 and 8, respectively. The Neck Disability Index was 26. The diagnosis of retrolisthesis at C5-C6 and cervical disk herniation with severe neuroforaminal narrowing at the left C5-C6 and C6-C7 levels were made with radiographs and magnetic resonance imaging. Posterior percutaneous endoscopic cervical diskectomy at the left C5-C6 and C6-C7 levels via an interlaminar shoulder approach was performed. During operation, a left-sided conjoined nerve root at the C6-C7 level was found (Video 1). Upon removal of a calcified disk and osteophytes at the C6-C7 level, the dura was torn slightly with traction without nerve root exposure or cerebrospinal fluid leakage. The 3-month postoperative follow-up visual analog scale scores of the neck and left upper limb were 0 and 0, respectively. The 3-month postoperative follow-up Neck Disability Index was 1. Posterior percutaneous endoscopic cervical diskectomy has become a favored treatment for cervical disk herniation because it offers sufficient decompression, smaller incisions, minimal blood loss, shorter hospital stay, and less postoperative pain.2,3 Nonetheless, if unexpected variation of the nerve root is noted during decompressive procedures, iatrogenic nerve root injury is a risk. Seven cases of cervical nerve root anomalies have been reported; all were found during posterior cervical surgery, which may indicate that the posterior approach provides better visualization of nerve root variants, especially in endoscopic surgery.4.

Feasibility and workflow analysis of IV-DSA-based augmented reality-guided brain arteriovenous malformation resection in a hybrid operating room: i-Flow tailored method.

Augmented reality (AR) has emerged as a promising technology in various medical fields.1 2 In the context of brain arteriovenous malformation (bAVM) surgery, AR offers the potential to enhance surgical visualization and improve procedural accuracy.3 4 5 6 This report aims to explore the application of digital subtraction angiography (DSA) from an IV contrast injection (IV-DSA) in AR-guided resection of bAVMs in a neurosurgical hybrid operating room.The workflow of IV-DSA-based AR-guided surgery for the resection of bAVMs consists of four main components: (1) acquiring source images through i-Flow tailored or multiphase scans (Siemens, Germany); (2) labelling targets in the workstation using Smartbrush software (Brainlab, Westchester, Illinois, USA); (3) using the Brainlab Curve navigation system; and (4) merging microscopic AR fusion using Zeiss Kinevo (AG, Germany). In video 1 we show the entire workflow and introduce i-Flow tailored IV-DSA data acquisition in the hybrid operating room. In summary, IV-DSA-based augmented reality is an innovative technique for bAVM surgery.neurintsurg;jnis-2023-020797v1/V1F1V1Video 1-i-flow tailored iv-DSA.

The residual exposed endplate ratio is predictive of posterior heterotopic ossification after cervical Bryan disc arthroplasty.

OBJECTIVES: Heterotopic ossification (HO), a major cause of dysfunction after disc arthroplasty (CDA). The aim of this study was to determine the cut value of the residual exposed endplate (REE) ratio and to predict the development of posterior HO after Bryan CDA. METHODS: This retrospective study investigated the relationship between the REE ratio and posterior HO formation after Bryan CDA. Consecutive adult patients who underwent 1- or 2-level Bryan CDA by a single neurosurgeon between 2006 and 2016 with at least two years follow-up were included. Postoperative radiographic analysis and measurement were performed to obtain the REE ratio and the HO grade. RESULTS: Of 249 patients with 384 surgical levels who underwent Bryan CDA during the study period, 114 (45.8 %) received 1-level CDA and 135 (54.2 %) received 2-level CDA. Lateral radiographs showed that 169 implants (44 %) had posterior HOs in all grades after two years or more of follow up and 14 implants (3.64 %) had severe HO (McAfee grades 3 and 4). In 329 implants (85.7 %), a comparison of radiographs to CT examination of HO grading showed a substantial relationship. Using area under the curve (AUC) analysis, a REE ratio >9 %, with 65.1 % sensitivity and 86.5 % specificity, was the cut point for posterior HO formation. CONCLUSIONS: REE is highly correlated with the development of postoperative posterior HO after Bryan CDA, regardless of the level of implantation. An undersized implant causing a REE ratio >9 % is a predictor of postoperative posterior HO formation after cervical Bryan CDA.

Tracheomalacia as Complication of Stenting for Esophageal Injury After Transsternal Approach to High Thoracic Vertebral Metastasis.

BACKGROUND: Esophageal injury is a severe surgical complication of a transsternal approach to high thoracic vertebral metastasis, which can result in mediastinitis and life-threatening consequences. A covered stent can be placed in the esophagus to prevent mediastinal leakage. However, tracheomalacia is a rare complication following esophageal stenting. CASE DESCRIPTION: A 56-year-old man had a pathologic fracture of the T3 vertebral body with spinal cord compression, myelopathy, and neurogenic bladder. An esophageal injury was noticed during the transsternal approach. Immediate suture repair, drainage tube placement, and subsequent esophageal stenting were carried out. One month after discharge, the endoscopic examination revealed nonhealing of the esophagus, and a new covered stent was replaced. Episodes of severe stridor and dyspnea led to the patient being sent to the emergency department. Computed tomography scan of the chest revealed a focal collapse of the trachea at the thoracic inlet, and tracheomalacia was suspected. The covered stent was removed, despite nonhealing of the esophagus. His stridor, dyspnea, and constant coughing subsided afterwards. The endoscopic examination at 3 months after stent removal showed complete healing of the esophagus. CONCLUSIONS: Esophageal stenting can be used to prevent mediastinal leakage due to esophageal injury in the transsternal approach for high thoracic vertebral metastasis, but the stent might be a cause of tracheomalacia. Stent removal should be considered if upper airway obstruction occurs. Awareness of the radial force of the stent, esophageal composition (e.g., status post suture repair), and esophageal diameter must be considered for optimal stent tolerance to avoid complications.

An Arthroscopic Technique for Long Head of Biceps Tenodesis With Double Knotless Screw.

Tenodesis of the long head of the biceps (LHB) is a frequently performed procedure during shoulder arthroscopy for the treatment of degenerative, traumatic, or inflammatory lesions of the LHB tendon. Arthroscopic techniques for LHB tenodesis using knotless screw techniques offer the advantage of circumventing the need for arthroscopic knot tying. In 2012 Song and Williams described a novel tenodesis technique that does not require any knot-tying procedures by using a knotless anchor. However, a single-anchor configuration may not offer adequate stabilization of the LHB tendon. Therefore we propose a modified method that uses a double knotless anchor that offers advantages over the single knotless anchor, such as an increase in the contact area between the tendon and bone to facilitate tendon-to-bone healing and strengthening of the tenodesis construct.