Vision Loss Following Vertebral Artery Injury during Surgery for Atlantoaxial Instability.

Background: A number of complications following surgery aimed at atlantoaxial fixation have been reported. However, there is no report in the literature describing visual loss following vertebral artery injury. Objective: Vision loss as a complication of vertebral artery injury during surgery for atlantoaxial fixation is reported. Material and Methods: This is a report of two patients who were operated for atlantoaxial instability by the Goel technique of atlantoaxial fixation. During surgery, there was an injury to the vertebral artery and the artery had to be sacrificed. Results: Both patients suffered severe visual loss following surgery. One patient had a partial visual recovery that started within few days of surgery while the other patient remained completely blind. Conclusions: Although rare, visual loss can be a complication of vertebral artery sacrifice during surgery for atlantoaxial stabilization.

Clinical outcome following multisegmental cervical spinal fixation in patients who recovered partially following injury.

OBJECTIVE: The clinical outcome following multilevel stabilization in patients who suffered cervical spinal injury and developed severe neurological deficits and then gradually partially recovered is evaluated. The basis of the surgical concept was that cervical spinal degeneration is a result of single or multilevel spinal instability and that spinal trauma exaggerates the instability. MATERIALS AND METHODS: During the period 2015-2020, 14 patients who suffered severe cervical spinal injury and could be included in the classification of spinal cord injury without computed tomography evidence of trauma were surgically treated. There were 11 males and 3 females. The ages ranged from 45 to 67 years, average being 53 years. Cervical canal stenoses related to degenerative spinal changes were observed in all patients. All patients suffered severe neurological deficits and within few days or weeks had shown significant but incomplete neurological recovery. The identification of the levels of unstable spinal segments was done on the basis of radiological and clinical parameters and direct observation of spinal instability in adjoining spinal segments. Transarticular fixation was done by Camille's transarticular fixation technique. Using ASIA score, modified JOA score, and Goel Clinical Grading Scale, the clinical course of the patients was monitored. RESULTS: All patients showed recovery in the neurological status. Recovery started in the immediate postoperative period and the improvement progressed during the period of follow-up. CONCLUSIONS: Surgery for spinal stabilization can be indicated even in cases that improve in the neurological function.

Retro-Odontoid and Retro-C2 Body Pseudotumor, Pannus, and/or Cyst. A Study Based on Analysis of 63 Cases.

OBJECTIVE: The potential significance of relationship of atlantoaxial instability with retro-odontoid pseudotumor, pannus, and/or cyst (RPC) is analyzed. METHODS: We searched the database of patients with craniovertebral junction-related instability treated by atlantoaxial fixation from January 2000 to March 2020. We identified 63 patients in whom there was an RPC in the region posterior to the odontoid process or posterior to the posterior aspect of the C2 body. RESULTS: The RPC was solid in 10 patients, predominantly cystic in 39 patients, and had both solid and cystic components in 14 patients. The vertical dimension of the RPC varied from 4.5 to 10.5 mm (average, 7.9 mm) and the transverse dimension ranged from 2 to 5.2 mm (average, 3.4 mm). In 51 patients, the RPC was in the midline and in 9 patients, it was eccentric in location. In 38 patients, there was erosion of the C2 body adjoining the RPC. Analysis of investigations showed that in 100% of patients, the dome of the RPC was in line with the most susceptible point of potential bone compression of neural structures. The RPC was eccentric in location in 9 patients presenting with torticollis. RPC indicated the presence of atlantoaxial instability even when there were no other positive and validated radiologic indicators. After atlantoaxial stabilization, the RPC spontaneously regressed or disappeared. Direct resection of the RPC was neither performed nor was necessary in any case. CONCLUSIONS: RPCs are secondary consequences of atlantoaxial instability and need not be primarily addressed by surgical resection. Their location suggests that they might have a neural protective function.

Atlantoaxial and Subaxial Cervical Spinal Instability in Two Cases with Neurofibromatosis-Type 1.

This is a report of two patients who were diagnosed to have NF-1. The patients had severe dystrophic soft tissue and bone changes leading to craniovertebral junction and subaxial cervical spinal instability and deformity. Both the patients underwent atlantoaxial and subaxial cervical spinal stabilization. No bone, soft tissue or tumor resection was done for decompression. Both patients had gratifying clinical recovery. Follow-up in both the patients is more than 12 months.

Outcome of Osteophytes After Only-Fixation as Treatment for Multilevel Cervical Spondylosis-A Minimum of 12 Months Follow-Up.

OBJECTIVE: This report analyzes the significance of osteophytes in the overall pathologic scheme in patients with single-level or multilevel cervical spinal degeneration. METHODS: From January 2010 to December 2018, 249 patients with cervical spondylosis were surgically treated. The alterations in ventral compression caused by disc bulges, osteophytes, and ligament buckling (disc-osteophye-ligament [DOL] complex) at single or multiple levels were evaluated after surgical treatment that involved only spinal fixation and did not involve any kind of bone or soft tissue decompression. Delayed (≥1 year after surgery) postoperative imaging was available in 165 patients and these patients formed the study group. Forty-five patients underwent facet distraction arthrodesis (group A), 106 patients underwent only-fixation involving transarticular screw insertion (group B), and 14 patients underwent hybrid fixation that involved both intra-articular spacers and transarticular fixation techniques (group C) as the surgical treatment. RESULTS: The size of the DOL complex at the segments that underwent fixation was reduced in 136 patients. The size of the DOL complex or its related dural or neural compression did not increase in any of the cases evaluated. Reduction in the size of DOL was more pronounced in patients in group A in both immediate postoperative and delayed images and in patients in group C at spinal levels at which facet distraction was performed using facet distraction spacers. CONCLUSIONS: Spinal stabilization reduces the size of osteophytes. Facet distraction spacers are more effective in reduction of the size of DOL in both immediate and delayed postoperative periods.

Atlantoaxial Instability as a Cause of Craniovertebral and Cervical Spinal Alterations and Dorsal Kyphoscoliosis.

BACKGROUND: Musculoskeletal and neural alterations secondary to chronic atlantoaxial instability are evaluated. CASE DESCRIPTION: An 11-year-old girl presented with major symptoms of progressively worsening dorsal kyphoscoliosis (spinal kyphoscoliosis [SKS]). In addition to dorsal SKS, investigations revealed multiple craniovertebral and cervical spinal musculoskeletal abnormalities, Chiari formation, and syringomyelia. Dynamic imaging revealed atlantoaxial instability. Atlantoaxial stabilization resulted in rapid improvement in SKS, regression of tonsillar herniation, and resolution of syrinx. CONCLUSIONS: The experience with the case showcases wide ranged spinal consequences as a result of chronic atlantoaxial instability.

Ossified Anterior Foramen Magnum Meningioma: Report of Long-Term Surgical Outcome.

BACKGROUND: Technical surgery-related issues for large ossified/calcified meningioma that encased one or both vertebral arteries located anterior to brainstem in the region of foramen magnum are discussed. Relatively long-term outcome of successful surgery is reported. CASE DESCRIPTION: Three women were operated on for symptoms of progressive quadriparesis. Investigations revealed ossified meningioma located anterior to the brainstem. One or both vertebral arteries were encased within the confines of the tumor. Large size, bone-hard consistency, location anterior to the brainstem, and intimate vascular relationship made the surgery a formidable surgical problem. A midline posterior suboccipital approach was used to resect these tumors. Radical tumor resection was achieved in all cases successfully. Tumor drilling or heavy tumor breaking instruments were not necessary to debulk the tumor. Histologic examination in all 3 cases revealed psammomatous meningioma. During the follow-up period that ranged from 2 to 12 years, all 3 patients were leading a normal life, and there has been no documented recurrence in any case. CONCLUSIONS: Successful resection of "ossified" meningioma is associated with satisfactory long-term clinical outcome.

Split Cord Malformation Type 1 (Bony Spur) Excision Using Microrongeur.

Split cord malformation is well documented and reported in various case series and reports in the literature. The excision of bony spur in type 1 split cord malformation is challenging due to the intricate pathologic anatomy. The standard method advocated is to excise the bony spur with the help of a high-speed microdrill and a forward cutting punch. We describe a novel method of using fine-tipped slender microrongeur, which can negotiate the narrow confines harboring the bony spur and protect the adjacent hemicords. The surgical nuances are detailed and discussed.

Tethered cord and Chiari formation: Analysis of treatment in a relatively rare clinical situation.

A 32-year-old male patient was operated for tethered cord associated with spinal lipoma. Further investigations showed the presence of basilar invagination, Chiari formation, and extensive syringomyelia. His neurological symptoms continued to worsen after the surgery, and over a 3-year period, he developed spastic quadriparesis and urinary retention and constipation. The patient was now treated by atlantoaxial fixation. Following the surgery, the patient improved in function in all four limbs and both the urinary and stool control. The presence of symptomatic Chiari formation in association with the tethered cord is a relatively rare clinical event. Surgical treatment of Chiari formation can result in a gratifying clinical recovery.