Thoracolumbar spinal abnormalities in Stickler syndrome

Musculoskeletal and Gait Characteristics in Patients with Stickler Syndrome: A Cross-Sectional Study

BACKGROUND

Stickler syndrome (SS) is a connective tissue disorder of fibrillary collagen with very variable clinical manifestations, including premature osteoarthritis and osteopenia. This musculoskeletal alteration may affect gait maturity or produce strength difficulties.

OBJECTIVE

Our aim was to describe the musculoskeletal characteristics, bone stiffness, gait kinematics, and kinetics of SS patients.

METHODS

This is a cross-sectional study of children and youngsters with SS recruited by telephone calls through the Spanish SS Association. All participants underwent an analysis of musculoskeletal characteristics, including a 3D gait analysis.

RESULTS

The sample included 26 SS patients, mainly boys (65.4%) with a median age of 11 (IQR 5-14). The manual muscle testing was normal in 88.5% of patients. The median distance covered in the 6-min walking test was 560.1 ± 113.4 m. Bone stiffness index scores were 70.9 ± 19.7 for children under 10 years and 88.3 ± 17.5 for children older than 10 years. The gait indicators GPS and GDI were: 7.4 ± 1.9 and 95.3 ± 9.7, respectively, for the left side and 6.8 ± 2.0 and 97.7 ± 9.5 for the right side, respectively.

CONCLUSIONS

In our series of patients with SS, we found muscle-articular involvement does not have a high impact on strength or gait problems. More work is needed to understand the effect of SS on the musculoskeletal system.

Quality of Life in Children and Adolescents with Stickler Syndrome in Spain

Objective: To describe the quality of life and daily functioning of Spanish children and adolescents living with Stickler syndrome (SS) and to estimate the prevalence of associated disease features in a representative sample. Methods: A cross-sectional study of children and adolescents with SS were recruited via telephone calls through the Spanish SS Association. All participants underwent a structured clinical interview and filled in questionnaires reporting their quality of life (EuroQol-5D, TSK-11, CHAQ and PedsQoL). The prevalence of the main features associated with the syndrome and the mean scores of the questionnaires were estimated with 95% confidence intervals (95% CI). Results: The recruited sample included 26 persons who were mainly children (mean age 10.4 ± 4.5 (SD) range: 5–14) and male (65.4%). The prevalence estimates of SS features were as follows: the presence of moderate pain (52%), hearing loss 67% (95% CI: 54.8 to 91.3) and myopia 96% (95% CI: 87.2 to 104.4). The mean scores of the QoL indices were as follows: 22.4 (95% CI: 19.2 to 25.5) (±7.5) for TSK-11; 76.2 (95% CI: 68.8 to 83.6) (±17.1) for PedsQoL, 0.8 (95% CI: 0.7 to 0.9) (±0.3) for EQ-5D and 0.61 (95% CI: 0.24 to 1.0) (±0.9) for the cHAQ functional index. Conclusions: Our results confirmed a high variability in syndrome-related manifestations, with a large prevalence of visual and hearing deficits, pain and maxillofacial alterations. These findings may facilitate the detection of the most prevalent problems in this population, which could be a target to be addressed during the treatment of children and adolescents with SS.

Schmorl's nodes: demystification road of endplate defects-a critical review

BACKGROUND

Schmorl's nodes (SN) were the first vertebral endplate defects described. Debate continues about their epidemiology, physiopathology, and clinical significance. The purpose of this work was to summarize and discuss available literature about SN.

METHODS

We have searched for relevant papers about SN until April 2020, with 104 articles have been reviewed.

RESULTS

More than half of the available literature described the epidemiological aspects of SN or reported rare clinical presentations and treatment options. The lack of a consensual definition of SN, among other endplate defects, contributed to difficulties in literature results' interpretation. Summing up, SN is a frequent vertebral defect at the thoracolumbar juncture, with ethnic and gender influence. Lumbar Schmorl's nodes were frequently associated with disc degenerative disease and back pain. Their physiopathology remains unknown. However, strain energy changes in the spine along with morphological aspects of the vertebra, the genetic background, and the osteoimmunology may constitute possible clues. New SN could be confused in malignancy context with bone metastasis. The literature describes some imaging techniques to differentiate them, avoiding invasive approaches. Treatment options for rare painful presentations remain few with low evidence. Further studies are needed to establish a consensual definition for SN, understand clinical aspects, and provide adequate therapeutic strategies.

The association between vertebral endplate structural defects and back pain: a systematic review and meta-analysis

PURPOSE

To clarify the current state of knowledge on the association of endplate structural defects and back pain.

METHODS

Five databases were searched for studies reporting on the association between endplate structural defects and back pain. Covidence and comprehensive meta-analysis software were used for article screening and selection and pooling of extracted data. Overall quality of evidence was assessed using GRADE.

RESULTS

Twenty-six studies comprised of 11,027 subjects met inclusion criteria. The presence of moderate heterogeneity (I² = 73%; p = 0.001) prevented the pooling of estimates across all studies. However, it was possible to pool studies of specific endplate defect phenotypes, such as erosion (OR: 2.69; 95% CI: 1.35-5.50) and sclerosis (OR: 1.97; 95% CI: 1.50-2.58), which yielded significant associations with back pain. Schmorl's nodes were also associated with most individual back pain phenotypes (OR: 1.53-1326, I² = 0-7.5%) and back pain overall (OR: 1.63, 95% CI: 1.37-1.94, I² = 26%) in general population samples. The pooling of data from all studies of specific back pain phenotypes, such as frequent back pain (OR: 2.83; 95% CI: 1.77-4.52) and back pain incidence (OR: 1.65; 95% CI: 1.30-2.10), each yielded significant association with endplate structural defects and was supported by low heterogeneity (I² =  < 7.5.%).

CONCLUSION

Overall, there is moderate quality evidence of an association between back pain and endplate structural defects, which is most evident for erosion, sclerosis and Schmorl's nodes. Going forward, research on specific endplate defect phenotypes and back pain case definitions using strong study designs will be important in clarifying the extent of associations and underlying mechanisms. The study was prospectively registered in Prospero (CRD42020170835) on 02/24/2020.

Challenging Diagnosis of Stickler Syndrome in a Patient with Premature Osteoarthritis: A Case Report

CASE

A 53-year-old male patient, subsequently diagnosed with type I Stickler syndrome, presented with severe premature osteoarthritis associated with bilateral hip dysplasia and knee epiphyseal dysplasia. Despite the presence of the typical manifestations of orofacial defects, hearing, ocular, and musculoskeletal abnormalities, the patient had never been diagnosed with the syndrome.

CONCLUSION

Stickler syndrome can present with a wide spectrum of musculoskeletal abnormalities without previous diagnosis. It is often underrecognized if the manifestations of other systems are not appreciated. Stickler syndrome should be considered in the differential diagnosis of patients with unexplained musculoskeletal abnormality particularly in the presence of other system manifestations.

Stickler Syndrome: A Review of Clinical Manifestations and the Genetics Evaluation

Stickler Syndrome (SS) is a multisystem collagenopathy frequently encountered by ophthalmologists due to the high rate of ocular complications. Affected individuals are at significantly increased risk for retinal detachment and blindness, and early detection and diagnosis are critical in improving visual outcomes for these patients. Systemic findings are also common, with craniofacial, skeletal, and auditory systems often involved. SS is genotypically and phenotypically heterogenous, which can make recognizing and correctly diagnosing individuals difficult. Molecular genetic testing should be considered in all individuals with suspected SS, as diagnosis not only assists in treatment and management of the patient but may also help identify other at-risk family members. Here we review common clinical manifestation of SS and genetic tests frequently ordered as part of the SS evaluation.

Therapeutic and diagnostic advances in Stickler syndrome

The Stickler syndromes are the leading cause of inherited retinal detachment and the most common cause of rhegmatogenous retinal detachment in childhood. The clinical and molecular genetic spectrum of this connective tissue disorder is discussed in this article, emphasising the key role the ophthalmologist has to play in the identification, diagnosis and prevention of blindness in the increasingly widely recognised sub-groups with ocular-only (or minimal systemic) involvement. Without diagnosis and prophylaxis in such high-risk subgroups, these patients are at high risk of Giant Retinal Tear detachment and blindness, especially in the paediatric population, where late or second eye involvement is common. Initially considered a monogenic disorder, there are now known to be at least 11 distinct phenotypic subgroups in addition to allied connective tissue disorders that can present to the clinician as part of the differential diagnosis.

Plain language summary

Treatment and diagnostic advances in Stickler syndrome The Stickler syndromes are a group of related connective tissue disorders that are associated with short-sight and a very high risk of blindness from detachment of the retina - the light sensitive film at the back of the eye. Other features include cleft palate, deafness and premature arthritis. It is the most common cause of retinal detachment in children and the most common cause of familial or inherited retinal detachment. In contrast to most other forms of blinding genetic eye disease, blindness from retinal detachment in Stickler syndrome is largely avoidable with accurate diagnosis and prophylactic (preventive) surgery. Recent advances in the understanding of the genetic causes of Stickler syndrome mean that the diagnosis can now be confirmed in over 95% of cases and, most importantly, the patient's individual risk of retinal detachment can be graded. Preventative surgery is hugely effective in reducing the incidence of retinal detachment in those patients shown to be at high risk. NHS England have led the way in the multidisciplinary care for patients with Stickler syndrome by launching a highly specialist service that has been free at point of care to all NHS patients in England since 2011 (https://www.england.nhs.uk/commissioning/spec-services/highly-spec-services, www.vitreoretinalservice.org).

Evidence of infectious disease, trauma, disability and deficiency in skeletons from the 19th/20th century correctional facility and asylum «Realta» in Cazis, Switzerland

As a reaction to widespread poverty, a system of coercive welfare developed in Switzerland during the 19^th century. Poverty was often thought to result from an individual’s misconduct rather than from structural, economic or political circumstances. People whose lifestyle deviated from the desired norm or who were unable to make a living for themselves were subjected to so-called administrative detention at institutions such as workhouses and poorhouses. The excavation of the cemetery of the correctional facility/workhouse and asylum «Realta» in Cazis offered the opportunity to gain insight into the living conditions of a marginalized group of people and to shed light on aspects of coercive welfare that have hardly been addressed in historical studies. A comprehensive study of pathological alterations was used to assess possible physical causes and effects of administrative detention. Skeletal samples from regular contemporaneous cemeteries provided data for the general population and thus allowed us to detect peculiarities in the «Realta» assemblage. Possible cases of Stickler Syndrome, microcephaly, congenital syphilis, endemic hypothyroidism and disabilities secondary to trauma may have been the reason for the affected individuals’ institutionalisation. The high prevalence of tuberculosis was linked to the socioeconomic status and the living conditions at the facility. Several cases of scurvy and osteomalacia may have resulted from various risk factors such as poverty, alcoholism, mental illness or institutionalisation. The fracture rates, especially of ribs, were extremely high. A large proportion of the fractures were incompletely healed and most likely occurred during detention due to interpersonal violence. Underlying diseases further contributed to the high fracture rates. This first study on skeletons from an institution of administrative detention in Switzerland demonstrated how pre-existing health conditions and the socioeconomic background contributed to the chance of being detained, and how detention led to further deterioration of health.

Imaging of Acute Low Back Pain

Acute low back pain, defined as less than 6 weeks in duration, does not require imaging in the absence of "red flags" that may indicate a cause, such as fracture, infection, or malignancy. When imaging is indicated, it is important to rule out a host of abnormalities that may be responsible for the pain and any associated symptoms. A common mnemonic VINDICATE can help ensure a thorough consideration of the possible causes.

Osteoporosis in Stickler syndrome. A new family case with bone histology study

The Stickler syndrome (SS) has been described as a "hereditary progressive arthro-ophtalmopathy" by Stickler in 1965, due to mutations on the collagen genes. Currently about 40 different genes have been identified which encode for at least 27 different collagens. The majority of mutations occur in the COL2A1 gene on chromosome 12q13 (SS type I). Mutations in COL11A1 are less frequent (SS type II). More recently, mutations in COL11A2 and in the COL9A1 gene have been reported with particular phenotypes. The main features of this autosomal inherited disease are ocular, auditory with orofacial abnormalities and early-onset osteoarthritis. We report the clinical presentation of an adult and his son, with a particular focus on the bone status of the father, radiography, bone densitometry and transiliac bone biopsy showing that he was suffering from osteoporosis. The lumbar bone mineral density was low with a Z-score at -2.9. Transiliac bone biopsy showed a dramatic decrease of trabecular bone volume (8.6%; Nl: 19.5±4.9%), thin trabeculae and a disorganized trabecular network. A slight increase of osteoid parameters was observed. Bone resorption was markedly increased with an excessive number of active (TRAcP+) osteoclasts. The cortical width was normal, but a slight increase of cortical porosity was found. Osteoporosis has been rarely described in the SS. It might be useful to systematically perform a bone densitometry in all patients with SS and to discuss the indication of a transiliac bone biopsy in severe cases.

Stickler Syndrome Type 1 with Short Stature and Atypical Ocular Manifestations

Stickler syndrome or hereditary progressive arthroophthalmopathy is a heterogeneous group of collagen tissue disorders, characterized by orofacial features, ophthalmological features (high myopia, vitreoretinal degeneration, retinal detachment, and presenile cataracts), hearing impairment, mild spondyloepiphyseal dysplasia, and/or early onset arthritis. Stickler syndrome type I (ocular form) is caused by mutation in the COL2A1 gene. Ptosis and uveitis are relatively rare ophthalmological manifestations of this syndrome. We report an Indian boy having 2710C>T mutation in COL2A1 gene demonstrating short stature, ptosis, and uveitis with Stickler syndrome.

mirVAFC: A Web Server for Prioritizations of Pathogenic Sequence Variants from Exome Sequencing Data via Classifications

Exome sequencing has been widely used to identify the genetic variants underlying human genetic disorders for clinical diagnoses, but the identification of pathogenic sequence variants among the huge amounts of benign ones is complicated and challenging. Here, we describe a new Web server named mirVAFC for pathogenic sequence variants prioritizations from clinical exome sequencing (CES) variant data of single individual or family. The mirVAFC is able to comprehensively annotate sequence variants, filter out most irrelevant variants using custom criteria, classify variants into different categories as for estimated pathogenicity, and lastly provide pathogenic variants prioritizations based on classifications and mutation effects. Case studies using different types of datasets for different diseases from publication and our in-house data have revealed that mirVAFC can efficiently identify the right pathogenic candidates as in original work in each case. Overall, the Web server mirVAFC is specifically developed for pathogenic sequence variant identifications from family-based CES variants using classification-based prioritizations. The mirVAFC Web server is freely accessible at https://www.wzgenomics.cn/mirVAFC/.

Dysplastic spondylolysis is caused by mutations in the diastrophic dysplasia sulfate transporter gene

Spondylolysis is a fracture in part of the vertebra with a reported prevalence of about 3-6% in the general population. Genetic etiology of this disorder remains unknown. The present study was aimed at identifying genomic mutations in patients with dysplastic spondylolysis as well as the potential pathogenesis of the abnormalities. Whole-exome sequencing and functional analysis were performed for patients with spondylolysis. We identified a novel heterozygous mutation (c.2286A > T; p.D673V) in the sulfate transporter gene SLC26A2 in five affected subjects of a Chinese family. Two additional mutations (e.g., c.1922A > G; p.H641R and g.18654T > C in the intron 1) in the gene were identified by screening a cohort of 30 unrelated patients with the disease. In situ hybridization analysis showed that SLC26A2 is abundantly expressed in the lumbosacral spine of the mouse embryo at day 14.5. Sulfate uptake activities in CHO cells transfected with mutant SLC26A2 were dramatically reduced compared with the wild type, confirming the pathogenicity of the two missense mutations. Further analysis of the gene-disease network revealed a convergent pathogenic network for the development of lumbosacral spine. To our knowledge, our findings provide the first identification of autosomal dominant SLC26A2 mutations in patients with dysplastic spondylolysis, suggesting a new clinical entity in the pathogenesis of chondrodysplasia involving lumbosacral spine. The analysis of the gene-disease network may shed new light on the study of patients with dysplastic spondylolysis and spondylolisthesis as well as high-risk individuals who are asymptomatic.

Osteoarthritis at young age, a diagnostic challenge: a case of stickler syndrome

A young woman presents with severe polyarticular osteoarthritis with relevant family history potentially suggesting a hereditary disease. Previously, the patient's mother had been diagnosed with rheumatoid arthritis and reported to have suffered from some locomotor problems. Careful clinical evaluation with an extensive personal and familial history pointed towards a diagnosis of Stickler syndrome, an autosomal dominant condition with progressive arthro-ophthalmopathy, (early osteoarthritis and myopia). Following this timely diagnosis, genetic counselling was offered.

Radiographic and tomographic analysis in patients with stickler syndrome type I

OBJECTIVE

To further investigate the underlying pathology of axial and appendicular skeletal abnormalities such as painful spine stiffness, gait abnormalities, early onset osteoarthritis and patellar instability in patients with Stickler syndrome type I. Radiographic and tomographic analyses were organized.

METHODS

From a series of Stickler syndrome patients followed from early life to late childhood. Ten patients (6 boys and four girls of different ethnic origins were consistent with the diagnosis of Stickler syndrome type I ). Phenotypic characterization was the baseline tool applied for all patients and genotypic correlation was performed on four families

RESULTS

A constellation of axial abnormalities namely; anterolateral ossification of the anterior longitudinal spinal ligament with subsequent fusion of two cervical vertebrae, early onset Forestier disease (progressive spinal hyperostosis with subsequent vertebral fusion on top of bridging osteophytes and "Bamboo-like spine" resembling ankylosing spondylitis) and severe premature spine degeneration were evident. Appendicular abnormalities in connection with generalized epiphyseal dysplasia were the underlying aetiology in patients with Intoeing gait and femoral anteversion, early onset severe osteoarthritis of the weight bearing joint. Remarkable trochleo-patellar dysplasia secondary to severe osteoarthritis causing effectively the development of patellar instability was additional pathology. Mutation of COL2A1 has been confirmed as the causative gene for Stickler syndrome type I CONCLUSION: We concluded that conventional radiographs and the molecular determination of a COL2A1 in patients with (Stickler syndrome type I) are insufficient tools to explain the reasons behind the tremendous magnitude of axial and appendicular skeletal abnormalities. We were able to modify the criteria of the clinical phenotype as designated by Rose et al in accordance with the novel axial and appendicular criteria as emerged from within our current study.

Stickler syndrome, ocular-only variants and a key diagnostic role for the ophthalmologist

The entity described by Gunnar Stickler, which included hereditary arthro-ophthalmopathy associated with retinal detachment, has recently been recognised to consist of a number of subgroups, which might now more correctly be referred to as the Stickler syndromes. They are the most common clinical manifestation of the type II/XI collagenopathies and are the most common cause of inherited rhegmatogenous retinal detachment. This review article is intended to provide the ophthalmologist with an update on current research, subgroups, and their diagnosis together with a brief overview of allied conditions to be considered in the clinical differential diagnosis. We highlight the recently identified subgroups with a high risk of retinal detachment but with minimal or absent systemic involvement--a particularly important group for the ophthalmologist to identify.

Osteochondritis dissecans and Osgood Schlatter disease in a family with Stickler syndrome

PURPOSE

Stickler syndrome is among the most common autosomal dominant connective tissue disorders but is often unrecognised and therefore not diagnosed by clinicians. Despite much speculation, the cause of osteochondrosis in general and osteochondritis dissecans (OCD) and Osgood Schlatter syndrome (OSS) in particular remain unclear. Etiological understanding is essential. We describe a pair of family subjects presented with OCD and OSS as a symptom complex rather than a diagnosis.

METHODS

Detailed clinical and radiographic examinations were undertaken with emphasis on the role of MRI imaging. Magnetic resonance imaging may allow early prediction of articular lesion healing potential in patients with Stickler syndrome.

RESULTS

The phenotype of Stickler syndrome can be diverse and therefore misleading. The expectation that the full clinical criteria of any given genetic disorder such as Stickler syndrome will always be present can easily lead to an underestimation of these serious inheritable disorders. We report here two family subjects, a male proband and his aunt (paternal sister), both presented with the major features of Stickler syndrome. Tall stature with marfanoid habitus, astigmatism/congenital vitreous abnormality and submucus cleft palate/cleft uvula, and enlarged painful joints with early onset osteoarthritis. Osteochondritis dissecans (OCD) and Osgood Schlatter syndrome (OSS) were the predominating joint abnormalities.

CONCLUSION

We observed that the nature of the articular and physeal abnormalities was consistent with a localised manifestation of a more generalised epiphyseal dysplasia affecting the weight-bearing joints. In these two patients, OCD and OSS appeared to be the predominant pathologic musculoskeletal consequences of an underlying Stickler's syndrome. It is empirical to consider generalised epiphyseal dysplasia as a major underlying causation that might drastically affect the weight-bearing joints.

Focus on the physical assessment of the infant with Stickler syndrome

Stickler syndrome is an autosomal dominant, genetic connective tissue disorder characterized by ocular, orofacial, auditory, and skeletal anomalies. The diagnosis of Stickler syndrome is often missed in the newborn period and diagnosed as simply Pierre Robin sequence. For these patients, complications and disabilities could be lessened by further analysis of the family history.Neonatal caregivers are responsible for the immediate care of the newborn with Pierre Robin sequence. The prudent healthcare profession will explore the origin of the condition to provide optimal comprehensive care to the infant and family. This article reviews the physical findings of Stickler syndrome including differentiation between similar syndromes. A systematic review of physical findings is included along with treatment options.

A functional polymorphism in COL11A1, which encodes the alpha 1 chain of type XI collagen, is associated with susceptibility to lumbar disc herniation

Lumbar disc herniation (LDH), degeneration and herniation of the nucleus pulposus of the intervertebral disc (IVD) of the lumbar spine, is one of the most common musculoskeletal diseases. Its etiology and pathogenesis, however, remain unclear. Type XI collagen is important for cartilage collagen formation and for organization of the extracellular matrix. We identified an association between one of the type XI collagen genes, COL11A1, and LDH in Japanese populations. COL11A1, which encodes the alpha 1 chain of type XI collagen, was highly expressed in IVD, but its expression was decreased in the IVD of patients with LDH. The expression level was inversely correlated with the severity of disc degeneration. A single-nucleotide polymorphism (c.4603C-->T [rs1676486]) had the most significant association with LDH (P=3.3 x 10(-6)), and the transcript containing the disease-associated allele was decreased because of its decreased stability. These observations indicate that type XI collagen is critical for IVD metabolism and that its decrease is related to LDH.

A new autosomal recessive form of Stickler syndrome is caused by a mutation in the COL9A1 gene

Stickler syndrome is characterized by ophthalmic, articular, orofacial, and auditory manifestations. It has an autosomal dominant inheritance pattern and is caused by mutations in COL2A1, COL11A1, and COL11A2. We describe a family of Moroccan origin that consists of four children with Stickler syndrome, six unaffected children, and two unaffected parents who are distant relatives (fifth degree). All family members were clinically investigated for ear, nose, and throat; ophthalmologic; and radiological abnormalities. Four children showed symptoms characteristic of Stickler syndrome, including moderate-to-severe sensorineural hearing loss, moderate-to-high myopia with vitreoretinopathy, and epiphyseal dysplasia. We considered the COL9A1 gene, located on chromosome 6q13, to be a candidate gene on the basis of the structural association with collagen types II and XI and because of the high expression in the human inner ear indicated by cDNA microarray. Mutation analysis of the coding region of the COL9A1 gene showed a homozygous R295X mutation in the four affected children. The parents and four unaffected children were heterozygous carriers of the R295X mutation. Two unaffected children were homozygous for the wild-type allele. None of the family members except the homozygous R295X carriers had any signs of Stickler syndrome. Therefore, COL9A1 is the fourth identified gene that can cause Stickler syndrome. In contrast to the three previously reported Stickler syndrome-causing genes, this gene causes a form of Stickler syndrome with an autosomal recessive inheritance pattern. This finding will have a major impact on the genetic counseling of patients with Stickler syndrome and on the understanding of the pathophysiology of collagens. Mutation analysis of this gene is recommended in patients with Stickler syndrome with possible autosomal recessive inheritance.

[Degenerative disorders of the lumbar spine Total disc replacement as an alternative to lumbar fusion?]

Spinal fusion is accepted worldwide as a therapeutic option for the treatment of degenerative disorders of the lumbar spine. Because there are only few evidence-based data available supporting the usefulness of lumbar spinal fusion, its questionable benefit as well as the potential for complications are the reasons for an ongoing discussion. In recent years, total disc replacement with implants has emerged as an alternative treatment. Although early results are promising, there is still a lack of evidence-based data as well as of long-term results for this technology. This article gives a critical update on the implant systems currently in use (SB Charité, Prodisc II L, Maverick, Flexicore, Mobidisc), which all have to be considered as "first-generation" implants. Morphological and clinical sequelae of the different biomechanical properties, designs, and materials have not yet been sufficiently investigated. There is no international consensus on the indication spectrum and on the preoperative diagnosis of discogenic low back pain. The same is true for the (minimally invasive) surgical access strategies. Complication rates seem to be somewhat lower compared to spinal fusion techniques. There are no standardized revision concepts in cases of implant failure. Lumbar disc replacement has opened a new era in spinal surgery with a still unproven benefit for the patient. It is strongly recommended that these techniques should only be applied by experienced and well-trained spine surgeons. Until evidence-based data are available, all patients should be treated under scientific study conditions with close postoperative follow-up.

Stickler syndrome: Clinical characteristics and diagnostic criteria

The purpose of this study was to establish diagnostic criteria for Stickler syndrome. Ninety patients from 38 families had complete evaluations for possible Stickler syndrome. Molecular confirmation of COL2A1 mutation status (type I Stickler syndrome) was available on 25 patients from six families. In the remaining 65 patients, 47 from 25 families were affected with Stickler syndrome and 18 from seven families were unaffected with Stickler syndrome. A diagnostic nosology based on type I Stickler patients with known COL2A1 mutations was applied to clinically affected and unaffected patients. A diagnostic scale of 9 points evaluated molecular data or family history data and characteristic ocular, orofacial, auditory, and musculoskeletal findings. A score of > or =5 was diagnostic of Stickler syndrome. These criteria demonstrate 100% sensitivity when applied to type I Stickler syndrome patients with known COL2A1 mutations, 98% sensitivity when applied to clinically affected Stickler patients, and 86% specificity when applied to patients unaffected based on clinical and/or molecular analysis. We conclude that diagnostic criteria based on type I Stickler patients with molecularly confirmed COL2A1 mutations appear to be sensitive and specific for the diagnosis of this syndrome and should be helpful to clinicians when making the diagnosis.

X-linked spondyloepiphyseal dysplasia tarda: molecular cause of a heritable platyspondyly

STUDY DESIGN

Report of a family affected with X-linked spondyloepiphyseal dysplasia tarda with special respect to radiologic alterations of the spine from puberty to the forth decade and to molecular analysis of the underlying genetic defect.

OBJECTIVES

To report the typical radiologic presentation of patients with X-linked spondyloepiphyseal dysplasia tarda and the diagnostic tool of mutation screening for that disease in order to avoid confusion with similar occurrences.

SUMMARY OF BACKGROUND DATA

Spondyloepiphyseal dysplasia tarda is a genetically heterogeneous disorder that frequently manifests itself with back pain starting around puberty. The X-linked recessive form (X-linked spondyloepiphyseal dysplasia tarda) affects males and is clinically characterized by an arm span markedly exceeding total height, a barrel chest deformity, and early development of degenerative joint disease. The disorder is caused by mutations in the SEDL gene located on Xp22.12-p22.31.

METHODS

Radiologic alterations of the cervical, thoracal, and lumbar spine were assessed in the affected family members and one suspected female carrier in correlation to age. All 6 exon codings for the SEDL gene were analyzed by primer cycle sequencing.

RESULTS

In 3 male patients from a French family, we identified a 5 base pair deletion in SEDL, exon 5 at position 267-271 (delAAGAC). Carrier status for the mutation could be confirmed in one female member of the family, which is inconspicuous in terms of spine and joint diseases. Radiologic abnormalities of the patients comprised generalized platyspondyly, a hump-shaped deformity of cervical, thoracal, and lumbar vertebral bodies as well as signs of retrospondylophytes, osteochondrosis, and spondylarthrosis.

CONCLUSIONS

X-linked spondyloepiphyseal dysplasia tarda should be kept in mind as a differential diagnosis in men with early onset of back pain and radiologic abnormalities of the vertebral bodies comprising platyspondyly and a central hump.

The Stickler syndrome: genotype/phenotype correlation in 10 families with Stickler syndrome resulting from seven mutations in the type II collagen gene locus COL2A1

PURPOSE

To evaluate a cohort of clinically diagnosed Stickler patients in which the causative mutation has been identified, determine the prevalence of clinical features in this group as a whole and as a function of age, and look for genotype/phenotype correlations.

METHODS

Review of medical records, clinical evaluations, and mutational analyses of clinically diagnosed Stickler patients.

RESULTS

Patients with seven defined mutations had similar phenotypes, though both inter- and intrafamilial variability were apparent and extensive. The prevalence of certain clinical features was a function of age.

CONCLUSION

Although the molecular determination of a mutation can predict the occurrence of Stickler syndrome, the variability observed in the families described here makes it difficult to predict the severity of the phenotype on the basis of genotype.