Management of failed Chiari decompression and intrasyringeal hemorrhage in Noonan syndrome: illustrative cases.

BACKGROUND: Noonan syndrome (NS) is a rare genetic RASopathy with multisystem implications. The disorder is typically characterized by short stature, distinctive facial features, intellectual disability, developmental delay, chest deformity, and congenital heart disease. NS may be inherited or arise secondary to spontaneous mutations of genes in the Ras/mitogen activated protein kinase signaling pathways. OBSERVATIONS: Numerous case reports exist detailing the association between NS and Chiari I malformation (CM-I), although this relationship has not been fully established. Patients with NS who present with CM-I requiring operation have shown high rates reoperation for failed decompression. The authors reported two patients with NS, CM-I, and syringomyelia who had prior posterior fossa decompressions without syrinx improvement. Both patients received reoperation with successful outcomes. LESSONS: The authors highlighted the association between NS and CM-I and raised awareness that patients with these disorders may be at higher risk for failed posterior fossa decompression, necessitating reoperation.

Management of Craniocervical Instability in Spondyloepiphyseal Dysplasia Congenita: Assessment of Literature and Presentation of Two Cases.

Spondyloepiphyseal dysplasia congenita (SEDC) is a rare autosomal dominant skeletal dysplasia resulting in impairment of type II collagen function. Phenotypically, this results in various skeletal, ligamentous, ocular, and otologic abnormalities. Platyspondyly, scoliosis, ligamental laxity, and odontoid hypoplasia are common, resulting in myelopathy in a high number of patients due to atlantoaxial instability. Despite patients undergoing surgical fixation, complication rates such as nonunion have been reported to be high. Here within, we present two patients treated with occipitocervical fusion for atlantoaxial instability and early symptoms of progressive myelopathy. We additionally provide a detailed review of the literature to inform practitioners of the spinal manifestations and clinical considerations in SEDC.

Delayed spinal epidural hematoma following T1 chance fracture: An illustrative case and review of the literature.

Background: A Chance fracture is a traumatic fracture of the thoracic or lumbar spine that occurs secondary to a flexion-distraction injury. Although patients with chance fractures rarely present with neurologic deficits, a subset may become symptomatic from spinal epidural hematomas (SEH) warranting emergent decompressive surgery. Case Description: An 87-year-old female on anticoagulation presented with a T1 Chance fracture after a fall. She was originally neurologically intact, but became paraplegic over the next 10 h. When the cervical/thoracic magnetic resonance revealed a SEH markedly compressing the cord between the C7-T1 levels, she underwent an emergent decompression; she also had a C5-T4 instrumented fusion. Postoperatively, she regained lower limb function, but expired on postoperative day 5 due to respiratory complications likely attributed to the prolonged surgery for the spinal instrumentation. Conclusion: Delayed SEH rarely occur following spinal Chance fractures. Here, an 87-year-old female on anticoagulation developed the 10-h delayed onset of a SEH with paraplegia attributed to a T1 Chance fracture at the C7-T1 level. Although she regained neurological function following the emergent decompression, she expired 5 days later likely due to the extended operative time/blood loss from the C5-T4 fusion that could have been avoided.

Temporary Internal Bracing for Pediatric Odontoid Synchondrosis Fracture.

Children are predisposed to injuries of the upper cervical spine given their relatively immature osteology, ligamentous laxity, underdeveloped musculature, and larger ratios of head to body mass. Odontoid process fractures involving the synchondroses are among the most common of these injuries. Though many of these fractures can be treated conservatively with external bracing, fractures with significant displacement that are unable to be reduced require operative management. In these cases, most patients undergo C1-2 posterior fusion with arthrodesis with permanent limitation to atlantoaxial range of motion (ROM). Here, we present a novel operative approach to manage odontoid synchondrosis fractures with temporary internal bracing via C1-2 posterior instrumentation without arthrodesis. We saw a three-year-old female who presented after a motor vehicle collision with a displaced odontoid synchondrosis fracture that was unable to be adequately reduced in a closed fashion. In an attempt to preserve maximal atlantoaxial ROM, temporary internal bracing was carried out with excellent results.

Operative Management of Spinal Deformity Secondary to Hajdu-Cheney Syndrome.

Hajdu-Cheney syndrome (HCS) is an exceedingly rare disease with fewer than 100 cases described in the medical literature. It is most strongly associated with a defect in the transmembrane protein NOTCH2. Though the exact mechanism in humans is not yet known, the defect results in various skeletal abnormalities including severe osteoporosis placing these patients at high risk for progressive spinal deformity. Due to various common syndromic features including ligamentous laxity, increased osteoclast activity, skeletal malformations, patency of cranial sutures, and the aforementioned severe osteoporosis, these patients require special consideration from treating surgeons. There are currently only nine reported cases of spinal surgery in HCS patients. Herein, we describe the cases of two patients with HCS requiring surgery for progressive spinal deformity. Six months following surgery, both patients reported excellent outcomes with significant improvement in symptoms.

Craniospinal Surgery in Hajdu-Cheney Syndrome: A Review of Case Reports.

Hajdu-Cheney syndrome (HCS) is a rare metabolic bone disorder that results in severe osteoporosis and various skeletal deformities. Craniospinal pathology is commonly associated with it, but surgical management is challenging due to the distorted anatomy, reduced bone strength, and fusion failure due to osteolysis. Hence, the surgical difficulty in these patients requires careful consideration. In this study, we systematically review all published operative cases and complications to provide a comprehensive review pertaining to the spine and/or cranium in patients with HCS. By highlighting these cases and their associated complications, we aim to prepare practitioners who treat this difficult pathology.