Schwartz-Jampel syndrome, otherwise referred to as chondrodystrophic myotonia or myotonic myopathy, causes muscle hypertrophy, stiffness, and weakness at a very young age, usually either immediately after birth or within the first year of an infant's life [1].

Limb flexion is restricted and is usually the first sign for which parents seek medical care. Infants also display a delay in development of motor abilities : walking is achieved significantly later in comparison to healthy individuals. However, children affected by SJS eventually attain the ability to walk and become self-reliant.

At an older age, patients report considerable joint flexion limitations and stiffened muscles, a symptom that is particularly experienced in the quadriceps. The syndrome also induces various skeletal irregularities, such as micrognathia, pectus carinatum, kyphosis, coxa valga, short femoral bones and a short neck [2]. The outer appearance of individuals affected by SJS is also dysmorphic: blepharophimosis with blepharospasm, flattened facies, eyelid hypertrichosis, and micrognathia. Defective capital femoral epiphyses is another sign associated with Schwartz-Jampel syndrome [3]. As far as the cognitive development of these individuals is concerned, the majority of SJS patients display normal intelligence, although mental disabilities may occur in up to 20% of the cases. SJS patients with significantly high intelligence are thought to be nonexistent.

Depending primarily on the age of onset, SJS is further classified into two categories: SJS1 and SJS2. SJS type 1 produces the initial symptoms approximately during childhood, whereas SJS type 2 is a congenital and rare sub-type of Schwartz-Jampel syndrome [4]. Schwartz-Jampel syndrome type I is further divided into two sub-categories, IA and IB, with the latter manifesting earlier in the course of the patient's life with more severe symptoms.

• Respiratory Insufficiency

  All patients had feeding and swallowing difficulties, respiratory insufficiency, abnormal appearance, muscle hypotonia, and postnatal short stature. Recurrent episodes of unexplained fever occurred in all and were the cause of death in 6 of 8 cases. [ncbi.nlm.nih.gov]

  insufficiency Respiratory impairment 0002093 Skeletal muscle atrophy Muscle degeneration Muscle wasting [ more ] 0003202 Sprengel anomaly High shoulder blade 0000912 Talipes equinovarus Club feet Club foot Clubfeet Clubfoot [ more ] 0001762 Testicular [rarediseases.info.nih.gov]

• Microstomia

  The main clinical features of this syndrome include generalized myotonic myopathy, skeletal dysplasia, blepharophimosis, microstomia, contracture of joints and short stature. [ncbi.nlm.nih.gov]

  The combination of skeletal and muscular abnormalities may result in oro‐dental manifestations such as atypical facies, with micrognathia, microstomia, pursed lips, crossbite, cleft palate, as well as mandibular hypoplasia, the risk of dentigerous cysts [doi.org]

  Examination revealed diagnostic features such as a short stature, dysmorphic facies, fixed facial expression, pursed lips, microstomia micrognathia, low-set ears, short neck, and pes planus [Figure 1]. [amhsjournal.org]

• Receding Chin

  The children display facial dysmorphism (a small forehead, a flat base of the nose, a receding chin, an irregular order of the teeth, low-set ears, a high-arched palate, low hair-line), kyphoscoliosis, pigeon breast, severe contractures of the knee and [ncbi.nlm.nih.gov]

  He had bushy eyelashes, flat forehead, receding chin, pursed mouth, high arched palate, and pinched upturned nose. [pediatricneurosciences.com]

• Prognathism

  Sasiadek and Hanna Gerber, Genetic Factors Involved in Mandibular Prognathism, Journal of Craniofacial Surgery, 10.1097/SCS.0000000000003627, 28, 5, (e422-e431), (2017). [doi.org]

• Myopathy

  From Wikidata Jump to navigation Jump to search autosomal recessive disease characterized by neuromyotonia and chondrodysplasia that has material basis in hypomorphic mutations in the HSPG2 gene on chromosome 1p36 myotonic myopathy, dwarfism, chondrodystrophy [wikidata.org]

  A muscle biopsy is usually compatible with a myopathy. Lastly, electromyography and nerve conduction studies have been employed to rule out the differential diagnosis, but their findings are usually normal. [symptoma.com]

  The main clinical features of this syndrome include generalized myotonic myopathy, skeletal dysplasia, blepharophimosis, microstomia, contracture of joints and short stature. [ncbi.nlm.nih.gov]

  Schwartz–Jampel syndrome Other names Myotonic myopathy, dwarfism, chondrodystrophy, ocular and facial anomalies, Dysostosis enchondralis metaepiphysaria, Catel-Hempel type Schwartz–Jampel syndrome is inherited in an autosomal recessive manner. [en.wikipedia.org]

• Skeletal Dysplasia

  dysplasia Burton syndrome myotonic chondrodystrophy SJS SCHWARTZ-JAMPEL SYNDROME, TYPE 1 Chondrodystrophic Myotonia Dysostosis enchondralis metaepiphysaria, Catel-Hempel type SCHWARTZ-JAMPEL SYNDROME, TYPE 1; SJS1 Sja Syndrome SJS1 Myotonic Myopathy, [wikidata.org]

• Muscle Weakness

  Woman with Leg Weakness and Atrophic Muscle Fibers on Biopsy 554 Case 89A A Woman with Muscle Weakness and a Skin Rash 559 Case 90 A Man with Muscle Pains 567 Case 91 An Older Woman with Progressive Muscle Weakness 572 Case 92 An HIVInfected Man with [books.google.com]

  Signs and symptoms may include muscle weakness and stiffness, abnormal bone development, joint contractures, short stature, small, fixed facial features, and eye abnormalities (some of which may impair vision). [globalgenes.org]

  "Schwartz-Jampel syndrome (SJS) is a rare genetic disorder characterized by abnormalities of the skeletal muscles, including muscle weakness and stiffness (myotonic myopathy); abnormal bone development (bone dysplasia); permanent bending or extension [thepetitionsite.com]

  weakness ; Myopia ; Myotonia ; Narrow mouth ; Narrow palpebral fissure ; Osteoporosis ; Overfolded helix ; Pectus carinatum ; Pes planus ; Platyspondyly ; Ptosis ; Pursed lips ; Short neck ; Short stature ; Shoulder flexion contracture ; Skeletal muscle [mousephenotype.org]

  It exhibits muscle stiffness, mild muscle weakness, and a number of minor morphological abnormalities. In affected patients, problems with motor development frequently become evident during the first year of life. [genome.jp]

• Coxa Vara

  […] developmental, eye, genetic, neurological Phenotypes Abnormality of femoral epiphysis ; Anterior bowing of long bones ; Autosomal recessive inheritance ; Blepharophimosis ; Cataract ; Congenital hip dislocation ; Coronal cleft vertebrae ; Coxa valga ; Coxa [mousephenotype.org]

  Skeletal and articular disorders consist chiefly of limitation of motion of the hips, wrist, toes, and spine, short vertebrae with brevicollis, fragmentation and flattening of femoral epiphyses, pectus carinatum, acetabular dysplasia, and coxa vara. [whonamedit.com]

  They include the following: Musculoskeletal problems Continuous spontaneous activity on an electromyogram Joint contractures Pectus carinatum (pigeon chest) Abnormal curvature of the vertebrae (scoliosis, kyphosis, lordosis) Hip dysplasia, including coxa [forgottendiseases.org]

  vara 0002812 Flat face Flat facial shape 0012368 Flexion contracture of toe 0005830 High palate Elevated palate Increased palatal height [ more ] 0000218 High pitched voice 0001620 Hip contracture 0003273 Hyperlordosis Prominent swayback 0003307 Hyporeflexia [rarediseases.info.nih.gov]

• Coxa Valga

  The syndrome also induces various skeletal irregularities, such as micrognathia, pectus carinatum, kyphosis, coxa valga, short femoral bones and a short neck. [symptoma.com]

  valga ; Coxa vara ; Decreased testicular size ; Delayed skeletal maturation ; Flat face ; Flexion contracture of toe ; Full cheeks ; Generalized hirsutism ; High pitched voice ; Hip contracture ; Hyporeflexia ; Inguinal hernia ; Intellectual disability [mousephenotype.org]

  […] the following: Musculoskeletal problems Continuous spontaneous activity on an electromyogram Joint contractures Pectus carinatum (pigeon chest) Abnormal curvature of the vertebrae (scoliosis, kyphosis, lordosis) Hip dysplasia, including coxa vara and coxa [forgottendiseases.org]

  valga 0002673 Coxa vara 0002812 Flat face Flat facial shape 0012368 Flexion contracture of toe 0005830 High palate Elevated palate Increased palatal height [ more ] 0000218 High pitched voice 0001620 Hip contracture 0003273 Hyperlordosis Prominent swayback [rarediseases.info.nih.gov]

• Short Neck

  The syndrome also induces various skeletal irregularities, such as micrognathia, pectus carinatum, kyphosis, coxa valga, short femoral bones and a short neck. [symptoma.com]

  The child had a short neck, blepharophimosis, flattened face, hypertrichosis of the eyelids, prominent eyebrows, high arched palate, low set ears, micrognathia, short stature, and skeletal deformities. [advbiores.net]

  neck ; Short stature ; Shoulder flexion contracture ; Skeletal muscle atrophy ; Skeletal muscle hypertrophy ; Talipes equinovarus ; Umbilical hernia ; Weak voice ; Wrist flexion contracture Associated Genes HSPG2 (Withdrawn symbols: PRCAN, SJS1, perlecan [mousephenotype.org]

  The main signs and symptoms of Schwartz-Jampel syndrome include the following: Short stature Bone abnormalities, such as short neck, outward-bowed chest, curved spine, hip deformity, and osteoporosis Joint contractures Muscle abnormalities, such as inability [patientworthy.com]

  Features include facial malformations (microstomia, micrognathia, retrognathia, blepharophimosis, short palpebral fissures, telecanthus, sad “fixed” facies, low-set ears, short neck), and musculoskeletal signs (myopathy, myotonia, muscular hypertrophy [accessanesthesiology.mhmedical.com]

• Mandibular Prognathism

  Sasiadek and Hanna Gerber, Genetic Factors Involved in Mandibular Prognathism, Journal of Craniofacial Surgery, 10.1097/SCS.0000000000003627, 28, 5, (e422-e431), (2017). [doi.org]

• Hyporeflexia

  Congenital hip dislocation ; Coronal cleft vertebrae ; Coxa valga ; Coxa vara ; Decreased testicular size ; Delayed skeletal maturation ; Flat face ; Flexion contracture of toe ; Full cheeks ; Generalized hirsutism ; High pitched voice ; Hip contracture ; Hyporeflexia [mousephenotype.org]

  Mental retardation (20%) and areflexia/hyporeflexia are described. [accessanesthesiology.mhmedical.com]

  He had proximal muscle hypertrophy, distal muscle wasting and generalized hyporeflexia. Bone X-ray revealed pseudofracture of humerus. [advbiores.net]

  Coxa vara 0002812 Flat face Flat facial shape 0012368 Flexion contracture of toe 0005830 High palate Elevated palate Increased palatal height [ more ] 0000218 High pitched voice 0001620 Hip contracture 0003273 Hyperlordosis Prominent swayback 0003307 Hyporeflexia [rarediseases.info.nih.gov]

• Abnormal Gait

  gait Abnormal walk Impaired gait [ more ] 0001288 Genu valgum Knock knees 0002857 Hip dysplasia 0001385 Hypertonia 0001276 Intellectual disability Mental deficiency Mental retardation Mental retardation, nonspecific Mental-retardation [ more ] 0001249 [rarediseases.info.nih.gov]

• Waddling Gait

  Patients have a waddling gait and frequently adopt a crouched stance because of joint stiffness. [bmcneurol.biomedcentral.com]

A detailed medical history including the symptoms for which the parents initially sought medical advice is pivotal for the diagnosis of Schwartz-Jampel syndrome. Parents typically report a difficulty flexing an infant's joints, hypertrophic muscles and mobility issues. A careful clinical examination will reveal signs related to SJS, such as myotonia, kyphosis, joint flexion restriction, blepharospasm, coxa valga, hypertrichosis of the eyelids and a general difficulty to perform basic movements.

The clinical findings can be validated by imaging modalities, such as radiographs that will illustrate kyphosis or shorter femoral bones [5]. Imaging modalities, however, contribute little to the final diagnosis. Blood tests are also of limited use: mild augmentation of creatine kinase in the serum or aldolase may be detected, findings which do not clearly suggest SJS. Genetic testing is available, but not on a commercial basis. Families, should, therefore, be referred to specialty referral centers that research the disease's genetic basis.

No specific findings or abnormalities on histological examination have been noted in SJS. A muscle biopsy is usually compatible with a myopathy. Lastly, electromyography and nerve conduction studies have been employed to rule out the differential diagnosis, but their findings are usually normal [5] [6].

• Delayed Bone Age

  bone age, epiphyseal anomaly, kyphosis, scoliosis, pectus carinatum, abnormal vertebral size/shape, anterior bowing of the long bones). [accessanesthesiology.mhmedical.com]

1. Mallineni S, Yiu C. Schwartz-Jampel syndrome: a review of the literature and case report. Special Care in Dentistry. June 2012; 32 (3): 105–111.
2. Schwartz O, Jampel RS. Congenital blepharophimosis associated with a unique generalized myopathy. Arch Ophthalmol. 1962 Jul; 68:52-7.
3. Farrell SA, Davidson RG, Thorp P. Neonatal manifestations of Schwartz-Jampel syndrome. Am J Med Genet 1987;27:799–805.
4. Snook RJ, Pascuzzi RM. Schwartz-Jampel Syndrome. NORD Guide to Rare Disorders. Philadelphia. 2003;586-87.
5. Sadanandavalli-Retnaswami C, Issac TG, Gayathri N, Shivaram S. Schwartz–Jampel syndrome. J Pediatr Neurosci. Apr-Jun 2015; 10(2):169-171.
6. Regalo SC, Vitti M, Semprini M, et al. The effect of the Schwartz-Jampel syndrome on masticatory and facial musculatures--an electromyographic analysis. Electromyogr Clin Neurophysiol. 2005 Apr-May; 45(3):183-9.