Scoliosis and congenital anomalies associated with Klippel-Feil syndrome types I-III

Klippel-Feil syndrome: Should additional examination be conducted?

PURPOSE

Klippel-Feil syndrome (KF) is a rare disease defined as single or multi-level cervical vertebra fusion. KF could be accompanied by other spinal anomalies or isolated, and in which case necessity of whole spine screening is not clearly known. KF is investigated in terms of prevalence, gender distribution, fusion types, and frequency of accompanying anomalies according to types of KF.

METHODS

Approval from our hospital's ethics committee was received for this single-center, retrospective study. Considering the exclusion criteria among the 40,901 cervical spine MRIs, 40,450 patients were included in the study. It was re-evaluated for KF, fusion level, classification, cervical scoliosis, and other musculoskeletal and spinal anomalies.

RESULTS

125 (0.309%) of 40,450 patients is diagnosed with KF, which is more common in women (P < 0.001). Single fused segment 106 (84.8%), multilevel fused segments 8 (6.4%), contiguous fused segments 11 (8.8%) are observed. Upper level KF is detected in 13 (10.4%) patients. The frequency of additional anomaly is significantly higher in upper level KF compared to other level fusions (P < 0.001, Chi-square t). The cervical scoliosis is diagnosed 34 (27%). In KF patients with scoliosis, the frequency of additional anomalies was significantly higher (P < 0.001, Chi-square t).

CONCLUSION

Klippel-Feil prevalence is 0.309%, it is frequently observed in women, and at C2-C3 level. Additional anomalies are especially associated with 'contiguous fused segments' and 'upper level' types. Klippel-Feil with scoliosis is an indicator of increased risk for associated anomalies, and examination of the whole spine is recommended.

Mitral Valve Regurgitation in Klippel-Feil Syndrome With Related Thoracic Deformity

Klippel-Feil syndrome, characterized by congenital fusion of any 2 or more cervical vertebrae, is a rare disorder in which skeletal and other organ system-related abnormalities have been reported. This article reports a case of mitral valve regurgitation in a patient with Klippel-Feil syndrome and related thoracic deformity who underwent mitral valvuloplasty. Postoperatively, the mitral valve regurgitation disappeared, and there has been no recurrence for 3 years. This case highlights mitral valvuloplasty via median sternotomy as an excellent treatment for mitral valve regurgitation in a patient with thoracic deformity related to Klippel-Feil syndrome.

A Novel Technique for Basilar Invagination Treatment in a Patient with Klippel-Feil Syndrome: A Clinical Example and Brief Literature Review

Objectives and Background: To present a novel technique of treatment for a patient with basilar invagination. Basilar invagination (BI) is a congenital condition that can compress the cervicomedullary junction, leading to neurological deficits. Severe cases require surgical intervention, but there is debate over the choice of approach. The anterior approach allows direct decompression but carries high complication rates, while the posterior approach provides indirect decompression and offers good stability with fewer complications. Materials and Methods: A 15-year-old boy with severe myelopathy presented to our hospital with neck pain, bilateral upper limb muscle weakness, and hand numbness persisting for 4 years. Additionally, he experienced increased numbness and gait disturbance three months before his visit. On examination, he exhibited hyperreflexia in both upper and lower limbs, muscle weakness in the bilateral upper limbs (MMT 4), bilateral hypoesthesia below the elbow and in both legs, mild urinary and bowel incontinence, and a spastic gait. Radiographs revealed severe basilar invagination (BI). Preoperative images showed severe BI and that the spinal cord was severely compressed with odontoid process. Results: The patient underwent posterior surgery with the C-arm free technique. All screws including occipital screws were inserted into the adequate position under navigation guidance. Reduction was achieved with skull rotation and distraction. A follow-up at one year showed the following results: Manual muscle testing results and sensory function tests showed almost full recovery, with bilateral arm recovery (MMT 5) and smooth walking. The cervical Japanese Orthopedic Association score of the patient improved from 9/17 to 16/17. Postoperative images showed excellent spinal cord decompression, and no major or severe complications had occurred. Conclusions: Basilar invagination alongside Klippel-Feil syndrome represents a relatively uncommon condition. Utilizing a posterior approach for treating reducible BI with a C-arm-free technique proved to be a safe method in addressing severe myelopathy. This novel navigation technique yields excellent outcomes for patients with BI.

Genetic insights into the 'sandwich fusion' subtype of Klippel-Feil syndrome: novel FGFR2 mutations identified by 21 cases of whole-exome sequencing

BACKGROUND

Klippel-Feil syndrome (KFS) is a rare congenital disorder characterized by the fusion of two or more cervical vertebrae during early prenatal development. This fusion results from a failure of segmentation during the first trimester. Although six genes have previously been associated with KFS, they account for only a small proportion of cases. Among the distinct subtypes of KFS, "sandwich fusion" involving concurrent fusion of C0-1 and C2-3 vertebrae is particularly noteworthy due to its heightened risk for atlantoaxial dislocation. In this study, we aimed to investigate novel candidate mutations in patients with "sandwich fusion."

METHODS

We collected and analyzed clinical data from 21 patients diagnosed with "sandwich fusion." Whole-exome sequencing (WES) was performed, followed by rigorous bioinformatics analyses. Our focus was on the six known KFS-related genes (GDF3, GDF6, MEOX1, PAX1, RIPPLY2, and MYO18). Suspicious mutations were subsequently validated through in vitro experiments.

RESULTS

Our investigation revealed two novel exonic mutations in the FGFR2 gene, which had not previously been associated with KFS. Notably, the c.1750A > G variant in Exon 13 of FGFR2 was situated within the tyrosine kinase domain of the protein, in close proximity to several established post-translational modification sites. In vitro experiments demonstrated that this certain mutation significantly impacted the function of FGFR2. Furthermore, we identified four heterozygous candidate variants in two genes (PAX1 and MYO18B) in two patients, with three of these variants predicted to have potential clinical significance directly linked to KFS.

CONCLUSIONS

This study encompassed the largest cohort of patients with the unique "sandwich fusion" subtype of KFS and employed WES to explore candidate mutations associated with this condition. Our findings unveiled novel variants in PAX1, MYO18B, and FGFR2 as potential risk mutations specific to this subtype of KFS.

Occipital dermal sinus associated with infectious teratoma in an adult patient affected by Klippel-Feil syndrome: Rare case report and literature review

Background

The Klippel-Feil syndrome (KFS) is a rare congenital anomaly characterized by the fusion of cervical vertebrae, which may be associated with other malformations, such as dermoid tumors and teratoma. Some theories explain the embryology of these associations. Another condition that may be present is the dermal sinus (DS), communication between intracranial tumors and the subcutaneous tissue, and predisposing infections. This case report aims to describe an association between these three pathologies as well as correlate them from the literature. This report was based on medical records retrospectively reviewed associated with the systematic bibliographical consultation using indexed databases based on inclusion and exclusion methods.

Case Description

An adult male patient, 24 years old, was admitted to our service, presenting fever and meningeal irritation as initial symptoms. In the patient's clinical history, he was diagnosed with an occipital DS in his childhood, which was previously instructed to be operated on by another neurosurgical team, but the patient chose not to perform the procedure. The magnetic resonance imaging investigation showed a DS associated with a cerebellar infected mass with 2 cm on its main diameter. The patient was treated with preoperative antibiotic therapy and underwent gross total surgical resection of the tumor as well as DS correction, confirmed in the histopathological examination as a teratoma. After surgery, further computed tomography scan analysis showed the presence of cervical vertebrae fusion, compatible with KFS diagnosis.

Conclusion

The association between KFS, cerebellar teratoma, and DS has not yet been described in the literature, with only the association of the first two being extremely rare.

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.

Clinical and Surgical Characteristics of Patients with Atlantoaxial Dislocation in the Setting of "Sandwich Fusion": A Case-Control Study

BACKGROUND

Patients with "sandwich" fusion (concomitant C1 occipitalization and C2-C3 nonsegmentation), a subtype of Klippel-Feil syndrome, are at particular risk for developing atlantoaxial dislocation (AAD). However, the clinical and surgical characteristics of AAD in patients with sandwich fusion have not been clearly defined.

METHODS

A retrospective case-control study with a large sample size and a minimum 2-year follow-up was performed. From 2000 to 2018, 253 patients with sandwich AAD underwent a surgical procedure; these patients constituted the case group, and a matching number of patients with non-sandwich AAD were randomly selected to form the control group. Clinical data from electronic medical records and various imaging studies were analyzed and compared. The Japanese Orthopaedic Association (JOA) scale was used to evaluate neurological function.

RESULTS

Patients with sandwich AAD, compared with patients with non-sandwich AAD, had symptom onset at a younger age (34.8 compared with 42.8 years; p < 0.001) and had a higher likelihood for myelopathy (87.4% compared with 74.7%; p < 0.001). Patients with sandwich AAD had a higher incidence of lower cranial nerve palsy (7.9% compared with 0.0%; p < 0.001), a lower preoperative JOA score (13.4 compared with 14.2; p < 0.001), and higher incidences of accompanying Type-I Chiari malformation (20.9% compared with 1.2%; p < 0.001) and syringomyelia (21.3% compared with 1.6%; p < 0.001). Finally, patients with sandwich AAD had higher likelihoods of undergoing transoral release (28.5% compared with 5.1%; p < 0.001) and use of salvage fixation techniques (34.4% compared with 6.3%; p < 0.001), and had lower postoperative results for the JOA score (14.9 compared with 15.9; p < 0.001) and improvement rate (43.8% compared with 58.2%; p < 0.001).

CONCLUSIONS

Patients with sandwich AAD demonstrated distinct clinical manifestations. Versatility involving the use of various internal fixation techniques and transoral release procedures was frequently required in the surgical management of these patients, and meticulous and personalized preoperative planning would be of paramount importance.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

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.

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.

Familial occurrence of skeletal developmental anomalies as a reflection of biological relationships in a genealogically documented Central European sample (19th to 20th centuries)

Skeletal developmental anomalies (SDA) are a subject of constant interest across scientific disciplines, but still mostly as isolates and curiosities. The aim of this study was to find out to what extent the occurrence of SDA reflects documented biological relationships. The skeletal remains of 34 individuals with known genealogical data were available, members of one family over four generations (19th to 20th centuries, Bohemia, Czech Republic), including some inbred individuals. The occurrence of 89 SDA was assessed on the basis of scopic morphological evaluation and X-ray and CT examinations. The degree of similarity between individuals was calculated using a "similarity coefficient" (SC). A linear model was used to test the relationship between positive values of the SC and the relatedness of biologically related individuals. Simultaneously, based on population frequencies of the evaluated anomalies, those that could be considered familial were recorded. A statistically significant relationship between morphological similarity and the biological distance between individuals was found. The greatest similarity was found among close relatives such as parents and children, siblings, or grandparents and grandchildren. The effect of increased consanguinity on the occurrence of anomalies was not confirmed, however. Seventeen SDA shared by closely related individuals were found in the sample, supporting the documented family relationships among them. Eleven of these were selected as possibly familial, but only five were statistically significant: an elongated styloid process, a cervical block vertebrae (arch, facet joints), hamate hamulus aplasia, anteater nose sign, and incomplete fusion of the S1 spinous process. There were also 28 cases of individual occurrences of 17 different SDA, without connection to the documented relationships between individuals.

Cervical disc arthroplasty for Klippel-Feil syndrome

OBJECTIVE

Klippel-Feil syndrome (KFS) is a congenital musculoskeletal condition characterized by improper segmentation of the cervical spine. This study aimed to evaluate outcomes of KFS patients who underwent cervical disc arthroplasty (CDA).

METHODS

Consecutive patients who underwent anterior cervical surgery were retrospectively reviewed. Those patients with KFS who received discectomy adjacent to the congenitally fused vertebral segments were extracted and grouped into either the fusion or the CDA group. Clinical and radiological evaluations included visual analog scales, Neck Disability Index (NDI), Japanese Orthopedic Association (JOA) scores, C2-7 range of motion (ROM), C2-7 Cobb angle, C2-7 sagittal vertical axis (SVA), and T1-slope.

RESULTS

Among 2320 patients, there were 41 with KFS (prevalence = 1.77%), who were younger than the entire cohort (53.3 vs 56.4 years). Thirty KFS patients had adjacent discs and were grouped into the CDA and fusion groups (14 vs 16). Type-I KFS with C3-4 involvement was the most common for both groups (92.8% vs 81.2% with 57% vs 50%, respectively). Post-operation, both groups demonstrated improvement of all the patient reported outcomes. The C2-7 ROM significantly decreased in the fusion group than that of pre-operation (12.8 ± 6° vs 28.1 ± 11.5°). In contrast, the CDA group successfully preserved C2-7 and segmental ROM without additional complications.

CONCLUSIONS

KFS is rare (prevalence = 1.77%) among cervical spine surgery patients, and it rarely affects the overall cervical spinal alignment, except that it decreases segmental mobility. CDA is a feasible option for KFS because it not only avoids long-segment fusion but also preserves segmental and global mobility.

Rare association of Klippel-Feil syndrome with situs inversus totalis and review of the genetic background

Klippel-Feil syndrome (KFS) is a rare congenital anomaly in forming the cervical vertebrae resulting in the fusion of two or more of the vertebrae. KFS is associated with many congenital anomalies, some of which are common and well known. Here, we report a child with an extremely rare association of KFS with situs inversus totalis (SIT). Both KFS and SIT are genetically heterogeneous and their co-occurrence suggests a high possibility of sharing the same underlying causative agent. Here, we review the genetic background that is known for these two conditions in the literature.

Images in Spine: A Rare Abnormal Bony Fusion

Klippel-Feil syndrome (KFS) is characterized by failed segmentation of the cervical spine leading to inappropriately fused vertebral bodies. A 64-year-old male with a previous L5-S1 decompression presented with significant neck pain with radiation into the entire right upper extremity and hand. Imaging demonstrated fusion of the vertebral bodies at C2-3, C4-6, and C7-T1 with associated disc bulges at C3-4 and C6-7. Common presentation of KFS includes significant spondylosis and cervical myeloradiculopathy in addition to the classic triad of short neck, low posterior hairline, and restricted neck motion. We present exemplary images of this rare condition to aid clinicians in future diagnoses.

Sprengel Deformity: Comprehensive Evaluation of Concomitant Spinal and Extraspinal Anomalies in 90 Patients

STUDY DESIGN

A retrospective, case series.

OBJECTIVE

The aim of this study is to evaluate the concomitant anomalies in patients with Sprengel deformity (SD).

SUMMARY OF BACKGROUND DATA

SD is the most common congenital anomaly of the shoulder. One or more associated anomalies may coexist in SD patients, similar to congenital scoliosis (CS); however, these anomalies and their relationship have not been studied in detail previously.

METHODS

SD patients who have applied to our institution between 2005 and 2019 were retrospectively reviewed. The patients were evaluated clinically and radiologically. The patients were divided in two groups as SD patients with CS and without CS, to analyze if these anomalies are present due to CS or SD. Physical examination findings, MRI, CT, and USG reports were analysed for accompanying pathologies. Patients with missing data were excluded. Student-t and Fisher's exact tests were used to compare the groups. Significance value was set as p = 0.05.

RESULTS

Ninety patients met inclusion criteria. The most common spinal anomaly was omovertebra, followed by spina bifida and Klippel-Feil. Tethered cord and diastematomiyelia were associated with CS (P = 0.0026 and P = 0.0057, respectively). The most common extra-skeletal anomaly was rib anomalies, followed by urinary and cardiac system anomalies. Rib anomalies were associated with CS (P = 0.00001).

CONCLUSION

Concomitant anomalies may accompany SD. The prognosis of SD may be affected by these anomalies. Therefore, patients should be evaluated for possible coexistent congenital anomalies.

LEVEL OF EVIDENCE

4.

Klippel Feil Syndrome: Clinical Phenotypes Associated With Surgical Treatment

STUDY DESIGN

Retrospective study.

OBJECTIVE

To define distinct Klippel-Feil syndrome (KFS) patient phenotypes that are associated with the need for surgical intervention.

SUMMARY OF BACKGROUND DATA

KFS is characterized by the congenital fusion of cervical vertebrae; however, patients often present with a variety of other spinal and extraspinal anomalies suggesting this syndrome encompasses a heterogeneous patient population. Moreover, it remains unclear how the abnormalities seen in KFS correlate to neurological outcomes and the need for surgical intervention.

METHODS

Principal component (PC) analysis was performed on 132 KFS patients treated at a large pediatric hospital between 1981 and 2018. Thirty-five variables pertaining to patient/disease-related factors were examined. Significant PCs were included as independent variables in multivariable logistic regression models designed to test associations with three primary outcomes: cervical spine surgery, thoracolumbar/sacral spine surgery, and cranial surgery.

RESULTS

Fourteen significant PCs accounting for 70% of the variance were identified. Five components, representing four distinct phenotypes, were significantly associated with surgical intervention. The first group consisted of predominantly subaxial cervical spine fusions, thoracic spine abnormalities and was associated with thoracolumbar/sacral spine surgery. The second group was largely represented by axial cervical spine anomalies and had high association with cervical subluxation and cervical spine surgery. A third group, heavily represented by Chiari malformation, was associated with cranial surgery. Lastly, a fourth group was defined by thoracic vertebral anomalies and associations with sacral agenesis and scoliosis. This phenotype was associated with thoracolumbar/sacral spine surgery.

CONCLUSION

This is the first data-driven analysis designed to relate KFS patient phenotypes to surgical intervention and provides important insight that may inform targeted follow-up regimens and surgical decision-making.

LEVEL OF EVIDENCE

3.

Pathological Features and Surgical Strategies of Cervical Deformity

Cervical deformity (CD) is a kind of disorder influencing cervical alignment. Although the incidence of CD is not high, this deformity can cause not only pain but also difficulties in daily activities such as swallowing and maintaining upright position. Even though the common cause of cervical deformity is still controversial, previous studies divided CD into congenital deformity and secondary deformity; secondary deformity includes iatrogenic and noniatrogenic deformity according to pathogenic factors. Due to the lack of relevant studies, a standardized evaluation for CD is absent. Even though the assessment of preoperative condition and surgical planning mainly rely on personal experience, the evaluation methods could still be summarized from previous studies. The objective in this article is to summarize studies on cervical scoliosis, identify clinical problems, and provide directions for researchers interested in delving deep into this specific topic. In this review, we found that the lack of standard classification system could lead to an absence of clinical guidance; in addition, the osseous landmarks and vascular distributions could be variable in CD patients, which might cause the risk of vascular or neurological complications; furthermore, multiple deformities were usually presented in CD patients, which might cause chain reaction after the correction of CD; this would prevent surgeons from choosing realignment surgery that is effective but risky.

Bilateral Multilevel Cervical Rib and Bilateral Omovertebra in Klippel-Feil Syndrome

BACKGROUND

Klippel-Feil syndrome was first described in 1912; a short neck, low posterior hairline, and decreased cervical joint range of motion are the classical triad of this disease. In this syndrome, which is rarely observed, the characteristics that have been reported include the following: scoliosis; Sprengel deformity; cervical rib; ear, nose, oral, and laryngeal abnormalities; structural abnormalities of the urinary system; and congenital heart diseases. However, bilateral omovertebra and bilateral multilevel cervical ribs have not been reported.

CASE DESCRIPTION

We aimed to present this rare syndrome via radiologic findings from cases with bilateral multilevel cervical rib and bilateral omovertebra.

CONCLUSIONS

Cases of Klippel-Feil syndrome may be accompanied by multiple abnormalities. We want to highlight the need for detailed examination of patients and lifestyle modification at an early age, before symptom appearance, as well as adaptation to habitual exercise.

Klippel-Feil syndrome misdiagnosed as spondyloarthropathy: case-based review

Spondyloarthropathy refers to any joint disease of the vertebral column, but the term is mainly used for a specific group of disorders called seronegative spondyloarthropathies (SpAs). The axial skeletal involvement, peripheral and extra-articular manifestations and an association with the major histocompatibility complex class I human leukocyte antigen-B27 (HLA B27) are commonly shared features of SpAs. Klippel-Feil syndrome (KFS) is a rare congenital disorder characterized by the fusion of one or more cervical vertebrae, accompanied by various skeletal and extra-skeletal anomalies. We report a case of an adult male patient with HLA B27 positivity presenting with chronic cervical spine pain accompanied by morning stiffness and periodic night pain, with radiologically confirmed ankylosis and fusion of several cervical segments. His medical history included urogenital abnormalities operated in childhood and mild mitral prolapse. Initially suspected diagnosis of an early axial form of SpA was rejected after thorough workup. Instead, the nature of vertebral defects along with the past medical history of urogenital and cardiac abnormalities pointed towards the diagnosis of KFS. HLA B27 presence can be a confounder in patients presenting with spinal pain and that is why the differential diagnosis of CSD-s and SpA can be challenging in some patients.

Expanding the clinical history associated with syndromic Klippel-Feil: A unique case of comorbidity with medulloblastoma

Klippel-Feil syndrome (KFS) is an exceedingly rare constitutional disorder in which a paucity of knowledge exists about the disease and its associated morbidity and mortality. We present a 4-year-old male with KFS, who notably was also diagnosed with large-cell anaplastic medulloblastoma. We evaluated the genetic basis of co-occurring KFS and medulloblastoma and the role of MYO18B as related to medulloblastoma. Constitutional and somatic variant and copy number analyses were performed from DNA-based exome studies, along with RNA-sequencing of tumor tissue, to elucidate the genetic etiology of the co-existing disease states. We identified novel constitutional compound heterozygous frameshift variants (NM_032608.5: p.Leu2257SerfsTer16 and p.Arg2220SerfsTer74) each encoding a premature stop of translation in MYO18B, consistent with a diagnosis of KFS. We did not identify any somatic variants of known relevance or disease-relevant therapeutic targets in the tumor. The somatic copy number profile was suggestive of Group 3γ medulloblastoma. Relative to pediatric brain tumors, medulloblastoma, particularly, Group 3, had increased gene expression of MYO18B. In summary, coexisting constitutional and somatic diagnoses in this patient enabled the elucidation of the genetic etiology of KFS and provided support for the role of MYO18B in tumor suppression.

Evaluation of a combined approach to the correction of congenital cervical or cervicothoracic scoliosis

BACKGROUND CONTEXT

An anteroposterior combined approach has been used for the treatment of congenital cervical or cervicothoracic scoliosis. However, its outcomes and surgical risks have not been clarified.

PURPOSE

We analyzed the characteristics of congenital cervical and cervicothoracic scoliosis and evaluated the outcomes of an anteroposterior combined approach for its treatment.

STUDY DESIGN

We carried out a retrospective clinical study of prospectively collected data.

PATIENT SAMPLE

Sixteen patients were treated between 2009 and 2013. Their average age was 9.2years.

OUTCOME MEASURES

Radiographic and surgical outcomes were measured and recorded. We compared morphological parameters and preoperative and postoperative results.

METHODS

All patients underwent surgery with a combined approach. The following radiographic parameters were measured: head tilt (HT), mandible incline (MI), shoulder balance (SB), structural and compensatory curves, cervical lordosis, C7 central sacral vertical line (C7-CSVL) ratio, C7 sagittal vertical axis (C7-SVA) ratio, C2-C7 SVA ratio, the angle between the upper endplate of the T2 vertebra and a horizontal line (T2 tilt), gravity line ratio. Demographic and surgical data were also collected.

RESULTS

On average, the duration of follow-up was 68.0 months, surgical blood loss was 675mL, and the duration of surgery was 400.5 minutes. The average correction rate was 64.9% in the structural curve and 29.5% in the compensatory curve. Statistical analysis showed that MI significantly correlated with HT and SB (p<.05). The C7-CSVL ratio correlated with the HT, MI, and SB (p<.05). The C7-SVA ratio correlated with the structural curve and cervical lordosis (p<.05), and the gravity line ratio correlated with the structural and compensatory curve, cervical lordosis, and C7-SVA ratio (p<.05). Moreover, there were correlations between the structural and compensatory curves as well as between the structural curve and cervical lordosis (p<.05). There were significant differences before and after surgery in HT, MI, and structural and compensatory curves. Four patients developed nerve root palsy after surgical correction and totally recovered by 6 months of follow-up.

CONCLUSION

The combined approach is an effective surgical option for congenital cervical or cervicothoracic scoliosis. The resection of the hemivertebra cannot only improve head-neck aesthetic appearance but can also maintain the growth potential of the neck.

Congenital deformation of the posterior arch of the atlas: Subluxation of the atlanto-axial joint with temporary quadriplegia

Instabilities of the craniocervical junction can be of rheumatic, traumatic, or congenital origin. The reported patient has a congenital malformation of the cervical spine, which is frequently observed in patients with Klippel–Feil syndrome. Her posterior arch of the atlas (C1) is hypoplastic and a chronic subluxation of the atlanto-axial joint would be possible. Although most common fusions in Klippel–Feil syndrome patients exist at C2/3, the majority of studies about Klippel–Feil syndrome deal with pediatric or adolescent individuals. Through extreme flexion of her neck, there was a compression of the spinal cord by the odontoid process. This led to a quadriplegia lasting about 10 min. Over the following weeks, all of her symptoms started to diminish. This situation turned out to be the third episode involving temporary neurological disorders in this 60-year-old female’s life.

Adult Klippel-Feil Syndrome: Haemodynamic Instability in the Prone Position and Postoperative Respiratory Failure

A 52-year-old patient with Klippel-Feil syndrome was scheduled for elective C1 dorsal laminectomy and occipitocervical stabilisation under general anaesthesia. Preoperatively she had bulbar symptoms and a history of recurrent aspiration pneumonia, but no evidence of cardiovascular disease. When she was turned prone she developed persistent tachycardia, hypotension and ST segment changes despite fluids, pressors and inotropes. Her condition improved when turned supine, but she had persistent ECG changes and a troponin rise was measured the following day. She was extubated two days postoperatively but aspirated again and subsequently died 12 days later from respiratory failure. If prone positioning is required in patients with Klippel-Feil syndrome we suggest meticulous positioning to avoid sternal compression of the heart. We also suggest thorough preoperative respiratory evaluation and elective postoperative intensive care as these patients are at high risk of developing postoperative respiratory failure.

The Prevalence of Klippel-Feil Syndrome: A Computed Tomography-Based Analysis of 2,917 Patients

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

To determine the prevalence of KFS in asymptomatic patients in New York State.

SUMMARY OF BACKGROUND DATA

Klippel-Feil syndrome (KFS) is characterized by congenitally fused cervical vertebrae and may not be diagnosed clinically because most patients do not have the classic triad of short neck, low posterior hairline, and decreased neck range of motion. KFS may be associated with abnormalities such as congenital scoliosis and deafness, and patients are at higher risk for neurologic injury following cervical spine trauma. The prevalence of KFS has not been evaluated in a large series but is estimated to occur every 40,000 births.

METHODS

A total of 3,534 cervical computed tomography (CT) scans at the emergency department of a level I trauma center were obtained during a one-year period. Duplicate scans and outside hospital imaging were excluded, resulting in 2,917 cervical CT scans for review. Demographic information was collected, and if KFS was present, level(s) fused, Samartzis classification type, and presence of cervical scoliosis and cervical spine fractures were recorded.

RESULTS

The prevalence of KFS was 0.0058% (1 in 172). Of the 17 subjects with KFS, 8 were female and 9 were male. The most commonly fused levels were C5-C6 and C2-C3. All 17 subjects were classified as Samartzis type I, with a single congenitally fused cervical segment. None of the subjects had cervical scoliosis or cervical spine fractures.

CONCLUSIONS

The prevalence of KFS in our series is much higher than previously described. Because clinical diagnosis may not be reliable, it is likely that this condition is underreported and may only be found incidentally on imaging.

LEVEL OF EVIDENCE

Level III.

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

Background:

Klippel–Feil syndrome (KFS) includes craniocervical anomalies, low posterior hairline, and brevicollis, with limited cervical range of motion; however, there remains no consensus on inheritance pattern. This study defines incidence, characterizes concurrent diagnoses, and examines trends in the presentation and management of KFS.

Methods:

This was a retrospective review of the Kid's Inpatient Database (KID) for KFSpatients aged 0–20 years from 2003 to 2012. Incidence was established using KID-supplied year and hospital-trend weights. Demographics and secondary diagnoses associated with KFS were evaluated. Comorbidities, anomalies, and procedure type trends from 2003 to 2012 were assessed for likelihood to increase among the years studied using ANOVA tests.

Results:

Eight hundred and fifty-eight KFS diagnoses (age: 9.49 years; 51.1% females) and 475 patients with congenital fusion (CF) (age: 8.33 years; 50.3% females) were analyzed. We identified an incidence rate of 1/21,587 discharges. Only 6.36% of KFS patients were diagnosed with Sprengel's deformity; 1.44% with congenital fusion. About 19.1% of KFS patients presented with another spinal abnormality and 34.0% presented with another neuromuscular anomaly. About 36.51% of KFS patients were diagnosed with a nonspinal or nonmusculoskeletal anomaly, with the most prevalent anomalies being of cardiac origin (12.95%). About 7.34% of KFS patients underwent anterior fusions, whereas 6.64% of KFS patients underwent posterior fusions. The average number of levels operated on was 4.99 with 8.28% receiving decompressions. Interbody devices were used in 2.45% of cases. The rate of fusions with <3 levels (7.46%) was comparable to that of 3 levels or greater (7.81%).

Conclusions:

KFS patients were more likely to have other spinal abnormalities (19.1%) and nonnervous system abnormalities (13.63%). Compared to congenital fusions, KFS patients were more likely to have congenital abnormalities such as Sprengel's deformity. KFS patients are increasingly being treated with spinal fusion.

Level of Evidence:

III

A Novel 12q13.2-q13.3 Microdeletion Syndrome With Combined Features of Diamond Blackfan Anemia, Pierre Robin Sequence and Klippel Feil Deformity

Diamond-Blackfan anemia (DBA) is a rare congenital erythroid aplasia with a highly heterogeneous genetic background; it usually occurs in infancy. Approximately 30–40% of patients have other associated congenital anomalies; in particular, facial anomalies, such as cleft palate, are part of about 10% of the DBA clinical presentations.

Pierre Robin sequence (PRS) is a heterogeneous condition, defined by the presence of the triad of glossoptosis, micrognathia and cleft palate; it occurs in 1/8500 to 1/14,000 births.

Klippel Feil (KF) syndrome is a complex of both osseous and visceral anomalies, characterized mainly by congenital development defects of the cervical spine.

We describe the case of a 22-years-old woman affected by DBA, carrying a de novo deletion about 500 Kb-long at 12q13.2-q13.3 that included RPS26 and, at least, others 25 flanking genes. The patient showed craniofacial anomalies due to PRS and suffered for KF deformities (type II). Computed Tomography study of cranio-cervical junction (CCJ) drew out severe bone malformations and congenital anomalies as atlanto-occipital assimilation (AOA), arcuate foramen and occipito-condylar hyperplasia. Foramen magnum was severely reduced. Atlanto-axial instability (AAI) was linked to atlanto-occipital assimilation, congenital vertebral fusion and occipito-condyle bone hyperplasia. Basilar invagination and platybasia were ruled out on CT and Magnetic Resonance Imaging (MRI) studies. Furthermore, the temporal Bone CT study showed anomalies of external auditory canals, absent mastoid pneumatization, chronic middle ear otitis and abnormal course of the facial nerve bones canal.

The described phenotype might be related to the peculiar deletion affecting the patient, highlighting that genes involved in the in the breakdown of extracellular matrix (MMP19), in cell cycle regulation (CDK2), vesicular trafficking (RAB5B), in ribonucleoprotein complexes formation (ZC3H10) and muscles function (MYL6 and MYL6B) could be potentially related to bone-developmental disorders. Moreover, it points out that multiple associated ribosomal deficits might play a role in DBA-related phenotypes, considering the simultaneous deletion of three of them in the index case (RPS26, PA2G4 and RPL41), and it confirms the association among SLC39A5 functional disruption and severe myopia.

This report highlights the need for a careful genetic evaluation and a detailed phenotype-genotype correlation in each complex malformative syndrome.

"Clinical triad" findings in pediatric Klippel-Feil patients

BACKGROUND

It has been propagated that patients with Klippel-Feil syndrome (KFS) exhibit "clinical triad" findings (CTFs), known as a short neck, low posterior hairline, and limited cervical range of motion (ROM). However, the literature has noted that up to 50 % of KFS cases may not present with such findings and the reasoning behind such assertions remains speculative. As such, the following study addressed the association between CTFs to that of congenitally-fused cervical segments and other risk factors in KFS patients.

METHODS

We conducted a retrospective clinical study based on prospectively collected radiographic data. Thirty-one KFS patients at a single institution were assessed. Radiographs were used to evaluate the location and extent of congenitally-fused segments (spanning the occiput (O) to the first thoracic vertebra (T1)), as well as examining coronal and sagittal cervical alignments based on the Samartzis et al. KFS classification. Clinical records were evaluated to account for the initial clinical assessment of CTFs. Patients were further stratified into two groups: Group 1 included patients noted to have any CTFs, while Group 2 included patients who had no such findings.

RESULTS

There were 12 males and 19 females (mean age at initial consultation: 9.7 years). No evidence of any of the CTFs was shown in 35.5 % of patients, whereas 38.7, 16.2 and 9.7 % were determined to have one, two or all three criteria, respectively. Limited cervical ROM was the most common finding (64.5 % of patients). In Group 1, 25 % had a short neck, 30 % a low posterior hairline, and 100 % exhibited limited cervical ROM. Group 1 had a mean of 3.9 fused cervical segments, whereas Group 2 had a mean of 2.5 fused cervical segments (p = 0.028). Age, sex-type, occipitalization and alignment parameters did not significantly differ to Group-type (p > 0.05). In Group 1, based on the Samartzis et al. Types I, II, and III, 16.7, 73.3, and 80.0 % of the patients, respectively, had at least one CTF.

CONCLUSIONS

Complete CTFs were not highly associated during the clinical assessment of young KFS patients. However, KFS patients with extensive, congenitally-fused segments (i.e. Samartzis et al. Type III) were significantly more likely to exhibit one of the components of the CTF, which was predominantly a limited cervical ROM. Clinicians managing young pediatric patients should not rely on the full spectrum of CTFs and should maintain a high-index of suspicion for KFS, in particular in individuals that exhibit associated spinal findings, such as congenital scoliosis.

Cervical Scoliosis: Clinical and Radiographic Outcomes

Study Design Retrospective study. Objective Cervical scoliosis is a rare condition that can arise from various etiologies. Few reports on the surgical management of cervical scoliosis exist. Our objective was to evaluate clinical and radiographic outcomes following surgical management of cervical scoliosis. Methods We evaluated our cervical spine surgical database for patients with cervical scoliosis (Cobb angle > 10 degrees) from 2005 to 2010. Demographic data including age, gender, diagnoses, and primary versus revision surgery was collected. Surgical data including procedure (anterior versus posterior), estimated blood loss (EBL), length of surgery, length of hospitalization, and complications was recorded. Preoperative and postoperative Cobb angle measurements and Neck Disability Index (NDI) scores were recorded. Results Cervical scoliosis was identified in 18 patients. We excluded 5, leaving 5 men and 8 women with an average age of 50.7 (median 52, range 25 to 65). The average follow-up was 40 months (median 36.5, range 5 to 87). An anterior-only approach was used in 6 cases (average 4 levels fused), 5 cases were posterior-only approach (average 8.7 levels fused), and 2 cases were combined anterior-posterior approach. The EBL was an average of 286 mL (median 150, range 50 to 900), the average surgical time was 266 minutes (median 239, range 136 to 508), and the average hospital stay was 2.7 days (median 2, range 1 to 7). Complications occurred in 7 patients, and 2 developed adjacent segment pathology. The average coronal Cobb angle preoperatively was 35.1 degrees (median 31, range 13 to 63) and corrected was 15.7 degrees (median 10.5, range 2 to 59) postoperatively (p < 0.005). The average NDI preoperatively was 24.9 (median 26, range 6 to 37) and was reduced to 17.8 (median 18, range 7 to 30) postoperatively (p < 0.02). Conclusion Surgical management of cervical scoliosis can result in deformity correction and improvement in patient outcomes. Higher rates of complications may be encountered.

Multiple Major and Minor Anomalies Associated With Klippel-Feil Syndrome: A Case Report

Klippel-Feil syndrome is defined as congenital fusion of two or more cervical vertebrae. In this article, we report a 55-year-old male patient with one-year history of neck pain, headaches, and one episode of syncope after a severe trauma. X-rays and magnetic resonance imaging of cervical spine revealed fused vertebral bodies of C2-C5. The major anomalies associated with Klippel-Feil syndrome (small stature, thoracic kyphoscoliosis, lumbar scoliosis, restricted opening mouth, and bilateral sensorineural hearing loss) as well as multiple minor anomalies (mild face asymmetry, high arched palate, rhinoscoliosis, high nasal bridge, inclined septi nasi, and thin upper lip) were detected. This is a rare case describing the anomalies of the nose in Klippel-Feil syndrome patients. Our patient had no central cord impairment following a severe trauma.

Malignant teratoma in Klippel-Feil syndrome: a case report and review of the literature

Introduction

Klippel–Feil syndrome is characterized by a congenital fusion of cervical vertebrae. Intracranial teratomas are nongerminomatous germ cell tumors and they account for 0.3 to 0.9% of all intracranial tumors. Teratomas with malignant transformation refer to lesions which give rise to malignant cancer of somatic type. The association between tumors of dermoid origin and Klippel–Feil malformation is extremely rare. Only 23 other cases have so far been reported, and only one case of dermoid tumor with areas of dedifferentiation on squamous cell carcinoma has been described.

Case presentation

We report the case of a 72-year-old white man with a 2-year history of gait and balance disturbances. A brain magnetic resonance imaging revealed a fourth ventricle neoplastic process with infiltrative features. He was operated through a suboccipital craniectomy with a C1 laminotomy and bilateral vertebral artery transposition. At 6-months follow-up, magnetic resonance imaging showed an early regrowth of the fourth ventricle tumor, with the same radiological features.

Conclusions

Patients with Klippel–Feil malformation could develop posterior fossa dermoid tumors. The malignant potential of such tumors must be considered and surgery is recommended. Particular attention must be focused on the histopathological analysis in order to identify possible foci of malignant transformation.

A novel syndrome of Klippel-Feil anomaly, myopathy, and characteristic facies is linked to a null mutation in MYO18B

BACKGROUND

Klippel-Feil anomaly (KFA) can be seen in a number of syndromes. We describe an apparently novel syndromic association with KFA.

METHODS

Clinical phenotyping of two consanguineous families followed by combined autozygome/exome analysis.

RESULTS

Two patients from two apparently unrelated families shared a strikingly similar phenotype characterised by KFA, myopathy, mild short stature, microcephaly, and distinctive facies. They shared a single founder autozygous interval in which whole exome sequencing revealed a truncating mutation in MYO18B. There was virtually complete loss of the transcript in peripheral blood, indicative of nonsense-mediated decay. Electron microscopy of muscle confirms abnormal myosin filaments with accompanying myopathic changes.

CONCLUSIONS

Deficiency of MYO18B is linked to a novel developmental disorder which combines KFA with myopathy. This suggests a widespread developmental role for this gene in humans, as observed for its murine ortholog.

Effects of cervical deep muscle strengthening in a neck pain: a patient with klippel-feil syndrome

[Purpose] This study aimed to identify the effects of cervical deep muscle strengthening (CDS) on neck pain in a patient with Klippel-Feil syndrome (KFS). [Subjects and Methods] The subjects was a 39 year-old woman with neck pain and KFS that included incomplete block vertebrae in the C2–3 segments and block vertebrae in the C6–7 segments. The subject performed an exercise program including cervical strengthening exercise (level 1) and CDS exercise (level 2) for 6 weeks. Neck pain intensity was measured using the visual analogue scale (VAS) and the pressure pain threshold (PPT). All measurements were obtained before and after the CDS exercise program. [Results] The VAS and PPT measurements decreased; range of motion in the cervical joint increased. [Conclusion] CDS exercises were effective interventions for reducing neck pain in a patient with Klippel-Feil syndrome.

Klippel-Feil syndrome in congenital scoliosis

STUDY DESIGN

Retrospective review.

OBJECTIVE

To investigate the clinical manifestations and radiological characteristics of Klippel-Feil syndrome (KFS) in congenital scoliosis (CS). To identify the incidence of spinal or extraspinal abnormities in KFS.

SUMMARY OF BACKGROUND DATA

KFS is an uncommon condition, characterized as improper segmentation of one or more cervical spine segments. "Scoliosis" is potentially the most common manifestation associated with KFS. However, the clinical manifestations and radiological characteristics of KFS in patients with CS are less reported.

METHODS

A total of 516 patients with CS from January 2009 to March 2013 were identified from a single institution. The demographic distribution and clinical and radiographical data were collected. Cervical regions were also designated as high (O-C2), mid (C2-C4), and low (C4-T1). The incidence of intra- and extraspinal abnormalities associated with KFS was investigated.

RESULTS

In total, 28 patients (5.42%) had been identified with KFS, which included 8 males and 20 females. The mean coronal cervical alignment was 20.6° and sagittal alignment was 29.9°. KFS type I was found in 14 patients (50.0%), type II in 6 (21.4%), and type III in 8 (28.6%). Congenitally fused cervical segment is more common in the mid and lower cervical spine region (85.7%, 24/28). In the 28 patients with KFS, 11 have intraspinal anomalies (32.1%) and 6 have extraskeletal anomalies (21.4%). Thirteen patients (46.4%) exhibited rib anomalies. The incidence of rib anomalies showed no significant difference in CS patients with KFS and without KFS (P>0.05). A half of the patients with KFS have hemivertebrae; however, the incidence of hemivertebrae showed no significant difference in CS patients with KFS and without KFS (P>0.05).

CONCLUSION

The incidence of KFS was 5.42% in patients with CS. Congenitally fused cervical patterns are more common in the mid and lower cervical spine region. The incidence of rib anomalies, intraspinal abnormities, and hemivertebra was not increased in CS patients with KFS.

LEVEL OF EVIDENCE

4.

Whole exome sequencing identifies a POLRID mutation segregating in a father and two daughters with findings of Klippel-Feil and Treacher Collins syndromes

We report on a father and his two daughters diagnosed with Klippel-Feil syndrome (KFS) but with craniofacial differences (zygomatic and mandibular hypoplasia and cleft palate) and external ear abnormalities suggestive of Treacher Collins syndrome (TCS). The diagnosis of KFS was favored, given that the neck anomalies were the predominant manifestations, and that the diagnosis predated later recognition of the association between spinal segmentation abnormalities and TCS. Genetic heterogeneity and the rarity of large families with KFS have limited the ability to identify mutations by traditional methods. Whole exome sequencing identified a nonsynonymous mutation in POLR1D (subunit of RNA polymerase I and II): exon2:c.T332C:p.L111P. Mutations in POLR1D are present in about 5% of individuals diagnosed with TCS. We propose that this mutation is causal in this family, suggesting a pathogenetic link between KFS and TCS.

Two case reports of an unusual association between Klippel-Feil syndrome and amyotrophic lateral sclerosis: Do they share same genetic defect?

Klippel-Feil syndrome (KFS) is an unusual skeletal disorder characterized by congenital fusion of two or more cervical vertebrae which can be sporadic or familial. KFS emerges to be a failure of the normal segmentation and fusion of the mesodermal somites during 3(rd) and 8(th) weeks of embryonic development. The triad of low posterior hairline, short neck, and restricted neck motion is present only in 50% and often associated with scoliosis, spina bifida, Sprengel's deformity, cervical ribs, deafness, cleft palate, renal anomalies, congenital heart defects, and so on because of heterogeneous nature of the disease. The significance of KFS lies in the secondary effects produced on the nervous system, which usually presents with features of progressive cord and brain stem compression with relatively minor trauma. We here report two cases of KFS presented in association with amyotrophic lateral sclerosis. Only two such cases have been described in the literature in 1954 and 1975.

Clinical, genetic and environmental factors associated with congenital vertebral malformations

Congenital vertebral malformations (CVM) pose a significant health problem because they can be associated with spinal deformities, such as congenital scoliosis and kyphosis, in addition to various syndromes and other congenital malformations. Additional information remains to be learned regarding the natural history of congenital scoliosis and related health problems. Although significant progress has been made in understanding the process of somite formation, which gives rise to vertebral bodies, there is a wide gap in our understanding of how genetic factors contribute to CVM development. Maternal diabetes during pregnancy most commonly contributes to the occurrence of CVM, followed by other factors such as hypoxia and anticonvulsant medications. This review highlights several emerging clinical issues related to CVM, including pulmonary and orthopedic outcome in congenital scoliosis. Recent breakthroughs in genetics related to gene and environment interactions associated with CVM development are discussed. The Klippel-Feil syndrome which is associated with cervical segmentation abnormalities is illustrated as an example in which animal models, such as the zebrafish, can be utilized to provide functional evidence of pathogenicity of identified mutations.

Surgical treatment in a patient with Klippel-Feil syndrome and anterior cervical meningomyelocele: a case report and review of literature

INTRODUCTION

Klippel-Feil syndrome (KFS) is considered a rare developmental disorder characterized by mono- or multisegmental fusion of the cervical vertebrae which is frequently associated with diverse non-osseous, e.g. neural, visceral, cardiopulmonary and genitourinary development anomalies. Anterior cervical meningomyelocele (MMC) in KFS has only been described in two previous patients, both with non-surgical treatment.

CLINICAL PRESENTATION

We present the case of a 26-year-old female suffering from KFS, presenting with progressive bilateral C6 paraesthesias, C7 and C8 motor weakness and myelopathy. Radiological imaging revealed incomplete osseous fusion of the vertebrae C2-Th1. The spinal cord was displaced ventro-caudally through a large anterior MMC, apparently fixed at the dorsal oesophagus, severely stretching the cervical nerve roots. Surgery was indicated due to progression of the symptoms and was performed through a combined partial sternotomy and ventral anterolateral cervical approach. Intraoperatively, both division of oesophago-dural adhesions and intradural untethering of adhesions of the myelon with caudal parts of the cele were performed. Evoked somatosensory potentials improved immediately and 6-day postoperative MRI revealed a nearly complete reposition of the spinal cord in its physiological position. Genetic sequence analyses ruled out mutation of the growth and differentiation factor 6 (GDF6). Apart from slight intermittent paraesthesia, symptoms resolved almost completely within weeks after operation. Both radiological and neurological improvement remained stable at 16 months of follow-up.

CONCLUSION

KFS with anterior cervical MMC is rarely seen and may require surgery in case of clincial signs of nerve root compression or myelopathy. Osseous decompression, untethering and adhesiolysis under electrophysiological monitoring can provide sufficient radiological and clinical improvement.

Genetic aspects of congenital and idiopathic scoliosis

Congenital and idiopathic scoliosis represent disabling conditions of the spine. While congenital scoliosis (CS) is caused by morphogenic abnormalities in vertebral development, the cause(s) for idiopathic scoliosis is (are) likely to be varied, representing alterations in skeletal growth, neuromuscular imbalances, disturbances involving communication between the brain and spine, and others. Both conditions are characterized by phenotypic and genetic heterogeneities, which contribute to the difficulties in understanding their genetic basis that investigators face. Despite the differences between these two conditions there is observational and experimental evidence supporting common genetic mechanisms. This paper focuses on the clinical features of both CS and IS and highlights genetic and environmental factors which contribute to their occurrence. It is anticipated that emerging genetic technologies and improvements in phenotypic stratification of both conditions will facilitate improved understanding of the genetic basis for these conditions and enable targeted prevention and treatment strategies.

Klippel-Feil syndrome associated with situs inversus: description of a new case and exclusion of GDF1, GDF3 and GDF6 as causal genes

OBJECTIVE

Klippel-Feil syndrome is characterized by faulty segmentation of two or more cervical vertebrae and, in its most severe form, consists of massive cervical vertebral fusion, short neck, low posterior hairline, and limitation of head movement. Several cases associating Klippel-Feil syndrome with situs inversus totalis have been reported. In the present study, we describe the clinical features of a novel case of Klippel-Feil syndrome associated with situs inversus totalis and searched for mutations in GDF1, GDF3 and GDF6 genes, which were recently implicated in the development of skeletal and visceral anomalies.

METHODS

A case of Klippel-Feil syndrome associated with situs inversus totalis underwent a full clinical examination including X-ray of cervical spine and thorax, abdominal ultrasound, and computerized tomography scanning of thorax and abdomen. PCR amplification and automated nucleotide sequencing of coding exons and intron-exon junctions of GDF1, GDF3, and GDF6 genes were performed in genomic DNA.

RESULTS

No molecular alterations were found in GDF1, GDF3 and GDF6 genes in this patient.

CONCLUSION

An additional patient associating Klippel-Feil syndrome and situs inversus totalis is reported. Mutations in GDF1, GDF3, and GDF6 genes were excluded as the cause of this unusual clinical association.

Aplasia of the anterior arch of atlas associated with multiple congenital disorders: case report

BACKGROUND AND IMPORTANCE

Congenital clefts and aplasias of the atlas vertebra are rare. A nonfused posterior arch occurs in 4% of the population; in contrast, a nonfused anterior arch occurs in only 0.1%. To the best of our knowledge, this is the first description of the combination of anterior arch aplasia and a cleft of the posterior arch of the atlas associated with Klippel-Feil and Treacher-Collins syndromes and Sprengel deformity.

CLINICAL PRESENTATION

An 11-year-old girl presented with neck pain and symptoms of myelopathy, including upper- and lower-extremity paresthesia. Computed tomography revealed significant congenital bony anomalies of the cervical spine, with congenital fusion of C2 through C5. There was aplasia of the anterior ring of C1 (A 2.3-cm gap was present within the anterior aspect of the lateral masses). The posterior elements of C3 and C4 were fused, and signs of Sprengel deformity were present. Magnetic resonance imaging revealed effacement of the ventral cerebrospinal fluid space at the craniocervical junction and mild mass effect at the cervicomedullary junction. Flexion and extension views showed abnormal motion at the craniocervical junction. There was no evidence of atlantoaxial instability, basilar invagination, or Chiari malformation. Occipito-C4-scapular fusion was performed to prevent spinal cord injury and further neurological symptoms. Postoperatively, the patient did extremely well, and her preoperative symptoms resolved.

CONCLUSION

We describe a rare case of aplasia of the anterior arch of the atlas and posterior arch midline cleft in association with Treacher-Collins syndrome, Klippel-Feil syndrome, and Sprengel deformity. The patient's atlantoaxial instability was managed surgically with a unique construct that provided occipito-C4-scapular fusion.

Scoliosis and segmentation defects of the vertebrae

The vertebral column derives from somites, which are transient paired segments of mesoderm that surround the neural tube in the early embryo. Somites are formed by a genetic mechanism that is regulated by cyclical expression of genes in the Notch, Wnt, and fibroblast growth factor (FGF) signaling pathways. These oscillators together with signaling gradients within the presomitic mesoderm help to set somitic boundaries and rostral-caudal polarity that are essential for the precise patterning of the vertebral column. Disruption of this mechanism has been identified as the cause of severe segmentation defects of the vertebrae in humans. These segmentation defects are part of a spectrum of spinal disorders affecting the skeletal elements and musculature of the spine, resulting in curvatures such as scoliosis, kyphosis, and lordosis. While the etiology of most disorders with spinal curvatures is still unknown, genetic and developmental studies of somitogenesis and patterning of the axial skeleton and musculature are yielding insights into the causes of these diseases.