Klippel-Feil: A constellation of diagnoses, a contemporary presentation, and recent national trends

Vertebral pattern and morphology is determined during embryonic segmentation

BACKGROUND

The segmented nature of the adult vertebral column is based on segmentation of the paraxial mesoderm during early embryogenesis. Disruptions to embryonic segmentation, whether caused by genetic lesions or environmental stress, result in adult vertebral pathologies. However, the mechanisms linking embryonic segmentation and the details of adult vertebral morphology are poorly understood.

RESULTS

We induced border defects using two approaches in zebrafish: heat stress and misregulation of embryonic segmentation genes tbx6, mesp-ba, and ripply1. We assayed vertebral length, regularity, and polarity using microscopic and radiological imaging. In population studies, we find a correlation between specific embryonic border defects and specific vertebral defects, and within individual fish, we trace specific adult vertebral defects to specific embryonic border defects.

CONCLUSIONS

Our data reveal that transient disruptions of embryonic segment border formation led to significant vertebral anomalies that persist through adulthood. The spacing of embryonic borders controls the length of the vertebra. The positions of embryonic borders control the positions of ribs and arches. Embryonic borders underlie fusions and divisions between adjacent spines and ribs. These data suggest that segment borders have a dominant role in vertebral development.

A Comprehensive Approach to the Diagnosis and Management of Klippel Feil Syndrome

Klippel-Feil Syndrome (KFS) is a rare genetic disorder characterized by the abnormal development of the cervical spine, leading to the fusion of two or more cervical vertebrae. The syndrome presents diverse symptoms, including limited neck movement, chronic pain, and neurological manifestations such as limb numbness or weakness. The severity of KFS can vary significantly, and treatment primarily focuses on symptom management and preventing complications such as scoliosis or spinal cord compression. Surgical interventions are often necessary for patients with complex forms of the syndrome. Interestingly, Chiari 1 malformation, a cranial anomaly affecting the brainstem, can coincide anatomically with KFS. In this case report, we present the case of a 9-year-old patient who sought medical attention due to persistent, unchanging neck pain. The patient's medical history was notable for developmental delays and cervical restraint observed during physical examination. Magnetic resonance imaging (MRI) findings revealed hydrocephalus and brainstem descent, indicating the presence of Chiari 1 malformation. Comprehensive MRI and CT scans were performed, and a management plan was formulated, primarily involving cranial surgery and physiotherapy. Implementation of the treatment approach resulted in significant improvement in the patient's symptoms. This case highlights the significance of considering Chiari 1 malformation as a potential comorbidity in patients diagnosed with KFS who present with persistent neck pain. Early detection and appropriate management of both conditions are crucial for achieving favorable outcomes and enhancing the quality of life for affected individuals. Understanding the complex interplay between KFS and Chiari 1 malformation is essential for providing comprehensive care and tailored treatment strategies. Further research is warranted to elucidate the underlying mechanisms linking these two conditions and to explore optimal management approaches for patients with dual pathology. By reporting this case, we contribute to the existing literature and increase awareness among healthcare professionals regarding the potential coexistence of KFS and Chiari 1 malformation. Continued efforts in identifying associated anomalies and optimizing therapeutic interventions will aid in improving patient outcomes and ensuring optimal care for individuals affected by these conditions.

Transmandibular Cervical Corpectomy for Persistent Spinal Cord Compression in a Patient With Klippel-Feil Syndrome: A Technical Note and Systematic Review

BACKGROUND

Few studies have described a transmandibular approach for decompression in a patient with Klippel-Feil syndrome (KFS) for cervical myelopathy.

OBJECTIVE

To describe the transmandibular approach in a KFS patient with cervical myelopathy and to perform a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

METHODS

A systematic review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Embase and PubMed databases were searched from January 2002 to November 2022 for articles examining patients with KFS undergoing cervical decompression and/or fusion for cervical myelopathy and/or radiculopathy were included. Articles describing compression due to nonbony causes, lumbar/sacral surgery, nonhuman studies, or symptoms only from basilar invagination/impression were excluded. Data collected were sex, median age, Samartzis type, surgical approach, and postoperative complications.

RESULTS

A total of 27 studies were included, with 80 total patients. Thirty-three patients were female, and the median age ranged from 9 to 75 years. Forty-nine patients, 16 patients, and 13 patients were classified as Samartzis Types I, II, and III, respectively. Forty-five patients, 21 patients, and 6 patients underwent an anterior, posterior, and combined approach, respectively. Five postoperative complications were reported. One article reported a transmandibular approach for access to the cervical spine.

CONCLUSION

Patients with KFS are at risk of developing cervical myelopathy. Although KFS manifests heterogeneously and may be treated through a variety of approaches, some manifestations of KFS may preclude traditional approaches for decompression. Surgical exposure through the anterior mandible may prove an option for cervical decompression in patients with KFS.

Prevalence and Risk Factors of Surgical Treatment for Klippel–Feil Syndrome

Background

Recently, there have been some reports on surgical treatment for Klippel–Feil syndrome, but the prevalence and risk factors of surgery have not been well evaluated. This study sought to find the prevalence and potential risk factors of surgical treatment.

Methods

A retrospective radiographic review of 718 Klippel–Feil syndrome patients seen at Peking University Third Hospital from January 2010 to October 2017 was performed. Parameters included age, gender, deformity, cervical instability, Samartzis classification, and surgical treatment. Based on the surgical treatment they received, patients were divided into a surgery group and a non-surgery group. Prevalence and possible risk factors of surgical treatment were assessed.

Results

A total of 718 Klippel–Feil syndrome patients, including 327 men and 391 women, with an average age of 46.8 years were enrolled. According to the Samartzis classification scheme, 621 cases (86.5%) were classified as type I, 48 cases (6.7%) were classified as type II, and 49 cases (6.8%) were classified as type III, respectively. The most commonly fused segments were C2–3 (54.9%) and C5–6 (9.3%). Of all 718 patients, 133 (18.5%) patients underwent surgical treatment, mainly via the posterior approach (69.9%). The clinical factors included age, gender, deformity, instability, and Samartzis classification. Men were more likely to require surgical treatment (p < 0.001). Patients with instability (p < 0.001) or patients with deformity (p = 0.004) were also more likely to undergo surgery. All three of these variables were included in the binary regression analysis. Finally, gender (p < 0.001) and unstable joints (p < 0.001) were identified to be independently associated with surgical treatment. Gender was the most important risk factor with men being 2.39 times more likely to have surgical treatment, while patients with instability were 2.31 times more likely to receive surgery.

Conclusion

The prevalence of patients with Klippel–Feil syndrome requiring surgery was 18.5%, with the majority undergoing posterior cervical surgery. Gender and instability were indemnified as independent risk factors leading to surgical treatment.

Klippel-Feil Syndrome: Clinical Presentation and Management

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Klippel-Feil syndrome (KFS) is a rare multisystem constellation of findings with congenital cervical fusion as the hallmark. The etiology is not fully understood.

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Recent studies have indicated that KFS is more prevalent than previously described.

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Hypermobility in the nonfused segments may lead to adjacent segment disease and potential disc herniation and myelopathy after minor trauma.

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Most patients with KFS are asymptomatic and can be managed nonoperatively. Surgical treatment is reserved for patients presenting with pain refractory to medical management, instability, myelopathy or radiculopathy, or severe adjacent segment disease.

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Patients with craniocervical abnormalities and upper cervical instability should avoid contact sports as they are at increased risk for spinal cord injury after minor trauma.

The craniovertebral junction, between osseous variants and abnormalities: insight from a paleo-osteological study

The bony components of the craniovertebral junction (CVJ) have been investigated in 172 skeletons, dug up from several archaeological sites, to define the frequency of developmental dysmorphisms, and to acquire qualitative and quantitative data about their morphology. A review of the pertinent literature is also presented. Twenty-five individuals (14.5%) exhibited at least one dysmorphism, which ranged from a condition of simple variant to a true malformation. Four individuals presented two or more anomalies at the same time (2.3% of the whole sample, 16% of the affected individuals). The most frequently observed abnormalities were: (i) the presence of a complete bony bridge in the atlas, forming a canal surrounding the vertebral artery (arcuate foramen, supertransverse foramen, and the simultaneous occurrence of arcuate foramen and supertransverse foramen); (ii) the presence of basilar processes. Basilar processes displayed a great variety in shape and dimension. They also differed with respect to their relationship with atlas and axis. The less frequently detected anomalies were: (i) complete absence of the posterior arch of C1, (ii) fusion of C2 and C3, and (iii) irregular segmentation of C2. A broad array of structural defects has been described at the CVJ. They may occur either isolated or as part of complex multisystem syndromes. Although harmless in many cases, they can notwithstanding cause severe, even life-threatening complications. When unrecognized, they may generate trouble during surgery. Hence, accurate knowledge of CVJ arrangement, including its multifarious variations, is a critical issue for radiologists, clinicians, surgeons, and chiropractors.

Klippel-Feil Syndrome: Pathogenesis, Diagnosis, and Management

Klippel-Feil syndrome (KFS), or congenital fusion of the cervical vertebrae, has been thought to be an extremely rare diagnosis. However, recent literature suggests an increased prevalence, with a high proportion of asymptomatic individuals. Occurring as a sporadic mutation or associated with several genes, the pathogenesis involves failure of cervical somite segmentation and differentiation during embryogenesis. Most commonly, the C2-C3 and C5-C6 levels are involved. KFS is associated with other orthopaedic conditions including Sprengel deformity, congenital scoliosis, and cervical spine abnormalities, as well as several visceral pathologies. There are several classification systems, some based on the anatomic levels of fusion and others on its genetic inheritance. Management of patients with KFS primarily involves observation for asymptomatic individuals. Surgical treatment may be for neurologic complaints, correction of deformity, concomitant spinal anomalies, or for associated conditions and varies significantly. Participation in sports is an important consideration. Recommendations for contact sports or activities depend on both the level and the number of vertebrae involved in the fusion. A multidisciplinary team should be involved in the treatment plan and recommendations for complex presentations.

Role of Atlas Assimilation in the Context of Craniocervical Junction Anomalies

Atlas assimilation (AA) may be associated with atlantoaxial dislocation, Chiari malformation (CM), and basilar invagination. The importance of AA in the context of craniocervical junction (CVJ) anomalies is unclear. Considering this context, this study's objective is to discuss the role of AA in the management of CVJ anomalies, especially in CM. A comprehensive literature review was performed. In addition, some illustrative cases were discussed on the basis of our review. Finally, we propose a theoretic algorithm to evaluate patients with AA and CM. AA is a proatlas segmentation anomaly that may be complete or incomplete. It may be totally asymptomatic or symptomatic as the result of transferred shifted forces onto the C1-2 joints, leading to clear instability (atlantoaxial dislocation) or mild C1-2 instability. Cautious surgical planning may be required due to associated vertebral artery anomalies. AA with concomitant C2-C3 segmentation failure is highly associated with late C1-C2 instability. CVJ decompression failure was reported in patients with CM and a low clivus canal angle (<130-135 degrees). Patients with assimilated anterior C1 arches usually have evident AAD. CM patients with AA generally have type 1 BI or type 2 BI and are reported with higher rates of CVJ instabilities when compared with those "pure" CM. Dynamic examinations may provide additional evidence of atlantoaxial instability. Although AA per se is not considered an unstable configuration, further and detailed evaluations of patients with CM associated with AA are necessary. Some associated unstable configurations required concomitant CVJ fixation.

The role of radiography in the study of spinal disorders

Despite the growing use of computed tomography (CT) and magnetic resonance imaging (MRI) in the study of spinal disorders, radiography still plays an important role in many conditions affecting the spine. However, the study and interpretation of spine radiograph is receiving less attention and radiologists are increasingly unfamiliar with the typical findings in normal and pathologic conditions of the spine. The aim of this article is to review the radiologic indications of radiograph in different pathologic conditions that affect the spine, including congenital, traumatic, degenerative, inflammatory, infectious and tumour disorders, as well as their main radiographic manifestations.

Klippel–Feil Syndrome with Multiple Cervical Anomalies Discovered Following Trauma

The approach to the upper cervical spine is a challenge for surgeons, not only for its complex anatomy but also for the great variety of pathologies. Klippel–Feil syndrome (KFS) is a congenital disease characterized by the fusion of two or more cervical segments and is associated with various musculoskeletal and vascular malformations. However, there is no consensus on the type of surgery, approach, level of fixation or fusion. We report the case of a KFS, associated with multiple anatomical variants, who suffered a traumatic cervical injury and underwent surgical treatment.

Surgical Treatment for Central Sleep Apnea due to Occipitocervical Compression Myelopathy in a Patient with Klippel-Feil Syndrome

BACKGROUND

Central sleep apnea (CSA) due to occipitocervical compression myelopathy is an extremely rare condition. Here we report a case of surgical treatment for CSA due to occipitocervical compression myelopathy in a patient with Klippel-Feil syndrome.

CASE DESCRIPTION

A 60-year-old man had become aware of a gradually progressive clumsiness and gait disturbance without any cause of injury 5 years before. He had complicated respiratory discomfort during sleep for the previous month and visited our hospital. Neurologic examination revealed severe myelopathy. Polysomnography showed CSA and Cheyne-Stokes respiration. Imaging findings showed C2-3 vertebral fusion and severe spinal cord compression caused by hypoplasia of the C1 posterior arch complicated by an anomaly of the vertebral artery. We diagnosed the patient with CSA due to occipitocervical compression myelopathy complicated by Klippel-Feil syndrome. After a simulation using a full-scale 3-dimensional model, resection of the C1 posterior arch and C4-5 laminoplasty was performed. After surgery, both clumsiness and gait disturbance gradually improved. Polysomnography 1 month after surgery showed that the CSA and the Cheyne-Stokes respiration disappeared.

CONCLUSIONS

Although a recent report has indicated the cause of sleep apnea in patients with rheumatoid arthritis and occipitocervical disorders as obstructive sleep apnea, a significant improvement of CSA was observed with decompression surgery in this case. Appropriate surgical planning resulted in a favorable outcome.

Klippel-Feil Syndrome with Cervical Diastematomyelia in an Adult with Extensive Cervicothoracic Fusions: Case Report and Review of the Literature

Split cord malformation (SCM) is a developmental disorder that is usually symptomatic and diagnosed in childhood. The majority of these lesions are in the thoracic and lumbar spine, with only 1%-3% of cases found in the cervical spine. This is a case report of a 55-year-old female patient with an unremarkable medical history who presented with neck pain. Upon workup, she was found to have extensive developmental anomalies throughout her cervical and thoracic spine, including an incidentally found type 2 SCM and multiple autofused vertebrae. There are only 6 similar studies published in the literature. There was extensive facet degeneration in her cervical spine, which was suspected to be the etiology of her neck pain. This case illustrates the rare finding of asymptomatic adult cervical SCM and the likely significance of her autofused vertebrae causing accelerated symptomatic facet spondylosis.