Effect of transtibial prosthesis weight on the contralateral knee joint in relation to the risk of osteoarthritis.

BACKGROUND: Individuals with transtibial amputation place more load on the contralateral lower extremity. A higher adduction moment at the knee joint has been shown to have an effect on the risk of osteoarthritis. OBJECTIVE: The aim of this study was to investigate the effect of weight-bearing of lower-limb prosthesis on the biomechanical parameters associated with the risk of contralateral knee osteoarthritis. STUDY DESIGN: Cross-sectional. METHODS: The experimental group of 14 subjects with unilateral transtibial amputation (13 males). The mean age was 52.7 ± 14.2 years, height 175.6 ± 6.3 cm, weight 82.3 ± 12.5 kg, and duration of prosthesis use 16.5 ± 9.1 years. The control group consisted of 14 healthy subjects with identical anthropometric parameters. Dual emission X-ray absorptiometry was used to determine the weight of the amputated limb. For gait analysis, 10 Qualisys infrared cameras and a motion sensing system on 3 Kistler force platforms were used. Gait was analyzed with the original, lighter, commonly used prosthesis, as well as the prosthesis loaded to the original limb weight. RESULTS: The gait cycle and kinetic parameters of the amputated and healthy limbs were more similar to those of the control group when using the weighted prosthesis. CONCLUSIONS: We recommend further research to more accurately specify the weight of the lower-limb prosthesis with respect to the prosthesis design and duration of use of the heavier prosthesis during the day.

A case of congenital multiple epiphyseal dysplasia from the Late Migration Period graveyard in Drnholec (Czech Republic).

OBJECTIVE: To contribute to differential diagnosis of multiple epiphyseal dysplasia (MED) in archeological and clinical contexts. MATERIALS: A skeleton of a 30- to 45-year-old male (grave no. 806) from the Late Migration Period graveyard in Drnholec-Pod sýpkou (Czech Republic), radio-carbon dated to AD 492-530. METHODS: Morphological and metric analyses. RESULTS: Significant pathological changes were noted on ossa coxae and proximal ends of the femora, which appear similar to changes associated with Legg-Calvé-Perthes disease. X-ray examination made it possible to rule out pseudoachondroplasia, rickets and metabolic bone diseases. CONCLUSIONS: The finding was evaluated as a probable case of congenital multiple epiphyseal dysplasia. SIGNIFICANCE: This case will contribute to the construction of estimates of the occurrence of this disease in historical populations and can be instructive for diagnostics in current medical practice. LIMITATIONS: The final diagnosis is limited by the lack of genetic analysis. SUGGESTION FOR THE FUTURE RESEARCH: Further clarification leading to diagnosis will benefit from genetic analysis and evaluation of skeletal remains throughout Europe.

Mutations in NOTCH2 in families with Hajdu-Cheney syndrome.

Hajdu-Cheney syndrome (HCS) is a rare genetic disorder whose hallmark is acro-osteolysis, shortening of terminal phalanges, and generalized osteoporosis. We assembled a cohort of seven families with the condition and performed whole exome resequencing on a selected set of affected patients. One protein-coding gene, NOTCH2, carried heterozygous truncating variants in all patients and their affected family members. Our results replicate recently published studies of HCS and further support this as the causal gene for the disorder. In total, we identified five novel and one previously reported mutation, all clustered near the carboxyl terminus of the gene, suggesting an allele specific genotype-phenotype effect since other mutations in NOTCH2 have been reported to cause a form of Alagille syndrome. Notch-mediated signaling is known to play a role in bone metabolism. Our results support a potential therapeutic role for Notch pathways in treatment of osteoporosis.

Ultrasound diagnosis of severe mesomelic dysplasia in two fetuses, associated with increased neck translucency and tetralogy of Fallot in one and cystic hygroma in the other.

Two stillborn male sibling fetuses born to the same parents had severe mesomelic dysplasia documented at ultrasound and confirmed by radiography and autopsy. The 17-week-old fetus with increased neck translucency had additional heart and great vessel anomalies consistent with tetralogy of Fallot. The 15-week-old fetus had a nuchal cystic hygroma. We posit that these sibs have a distinct, previously unreported skeletal dysplasia. The mode of genetic transmission could be autosomal recessive or X-linked recessive.

Case reports: Legg-Calvé-Perthes disease in Czech archaeological material.

Legg-Calvé-Perthes disease (osteochondrosis of the femoral head) has been recognized in archaeological material for nearly a century but is extremely rare. We describe two Czech cases from archaeological findings. The first case was diagnosed in the skeleton of a man older than 50 years with the left hip affected. The skeleton was in grave Number 2 of the Langobard cemetery at Luzice (Moravia) and dated to the end of the fifth century and the beginning of the sixth century AD. The second case was described by J. Chochol in 1957 on the left femur and half of the pelvis of a skeleton from an archaeological investigation in Brandýsek (Bohemia), ninth to tenth centuries AD. Using the diagnostic criteria of Ortner and Putschar, we excluded slipped capital femoral epiphysis in both cases. We discuss the differential diagnosis of Legg-Calvé-Perthes disease versus unilateral and bilateral osteochondroses of the femoral head in archaeological and current clinical material.

Czech dysplasia metatarsal type: another type II collagen disorder.

Czech dysplasia metatarsal type is an autosomal-dominant disorder characterized by an early-onset, progressive spondyloarthropathy with normal stature. Shortness of third and/or fourth toes is a frequently observed clinical feature. Similarities between individuals with this dysplasia and patients with an R275C mutation in the COL2A1 gene, prompted us to analyze the COL2A1 gene in the original families reported with Czech dysplasia. Targeted sequencing of exon 13 of the COL2A1 gene was performed, followed by sequencing of the remaining exons in case the R275C mutation was not identified. We identified the R275C substitution in two of the original patients reported with Czech dysplasia and three additional patients. All affected individuals had a similar phenotype characterized by normal height, spondyloarthropathy, short postaxial toes and absence of ocular and orofacial anomalies. The R275C mutation was excluded in a third patient reported with Czech dysplasia. However, the identification of the Y1391C mutation in this patient with disproportionate short stature made the diagnosis of spondyloperipheral dysplasia (SPD) more probable. The Y1391C mutation is located in the C-propeptide of the procollagen chain and has been reported before in a patient with the Torrance type of lethal platyspondylic skeletal dysplasia (PLSD-T). Our observation of the same Y1391C mutation in an additional unrelated patient with SPD further supports the evidence that PLSD-T and SPD represent a phenotypic continuum. The R275C mutation in the COL2A1 gene causes a specific type II collagen disorder that was recently delineated as Czech dysplasia.

Eight mutations including 5 novel ones in the COL1A1 gene in Czech patients with osteogenesis imperfecta.

BACKGROUND AND AIM: Osteogenesis imperfecta (OI), also called brittle bone disease, is a clinically and genetically heterogeneous disorder characterized by decreased bone density. Autosomal dominant forms result from mutations in either the COL1A1 (collagen type I alpha-1 chain) or COL1A2 (collagen type I alpha-2 chain) genes encoding the type I collagen. The aim of this study was to identify mutations and allelic variants of the COL1A1 gene in patients with osteogenesis imperfecta (OI). METHODS AND RESULTS: Molecular genetic analysis of the COL1A1 gene was performed in a cohort of 34 patients with OI. The DNA samples were analysed by PCR and Sanger sequencing. DNA changes in coding sequences of the gene were compared with Type 1 Collagen Mutation Database. Genetic variants resulting in either quantitatively or structurally defective protein production were found in 6 unrelated patients. Four identified mutations are connected to decreased protein production (Tyr47X, Arg131X, Arg415X, Gln1341X), 2 result in amino acid substitution (Cys61Phe, Pro1186Ala) and the last affects splicing (c.1057-1G>T). Further, one silent mutation (Gly794Gly) was detected. No protein analysis was performed. CONCLUSION: Of the 8 identified mutations, 5 were novel and have not been reported before. Only one causes substitution of glycine located within the Gly-X-Y triplets in the triple helical domain. Two mutations are located in major ligand binding regions (MLBR) which are important for bone strength and flexibility. Although the genotype-phenotype correlation is still unclear, our findings should contribute to elucidating this relationship in patients diagnosed with OI.

The radiographic method for evaluation of axial vertebral rotation - presentation of the new method.

The objective of this study is to present a new radiographic method for the assessment of vertebral rotation from an antero-posterior view of conventional X-rays which is sufficiently precise in comparison with radiographic methods presently used in clinical practice (methods of Nash-Moe and Perdriolle). This method is based on the properties of the geometric shape of vertebrae and their shared dimensional proportions. It means that the relation between vertebral body width and height doesn't change significantly within the entire thoracic and lumbar sections of the spine. In order to verify the method, we have constructed a special device for vertebral fixation. Subsequently, the X-ray pictures of individual human vertebrae with predefined rotation values (ranging from 0 degrees to 45 degrees by steps of 3 degrees) were radio-graphically measured and then compared with their actual axial rotation on the vertebral rotation device. All arithmetic averages correlate very closely with the actual values. The verification of axial vertebral rotation with the assistance of CT and MRI pictures of six scoliotic patients (in supine position) and the evaluation of axial vertebral rotation by both the new radiographic method and with the Perdriolle method proved the satisfactory accuracy of our method. The main advantage of the newly presented radiographic method is the uncomplicated measurement of vertebral rotation from AP projection of conventional X-ray pictures or from its printed copies. The gold standard of the new radiographic method is the evaluation of axial rotation of vertebrae to 30 degrees approximately and the shape of vertebral bodies without severe structural deformities. The new radiographic method seems to be suitable for use in clinical practice.

New predictive model for monitoring bone remodeling.

The aim of this article was to present a new thermodynamic-based model for bone remodeling which is able to predict the functional adaptation of bone in response to changes in both mechanical and biochemical environments. The model was based on chemical kinetics and irreversible thermodynamic principles, in which bone is considered as a self-organizing system that exchanges matter, energy and entropy with its surroundings. The governing equations of the mathematical model have been numerically solved using Matlab software and implemented in ANSYS software using the Finite Element Method. With the aid of this model, the whole inner structure of bone was elucidated. The current model suggested that bone remodeling was a dynamic process which was driven by mechanical loading, metabolic factors and other external contributions. The model clearly indicated that in the absence of mechanical stimulus, the bone was not completely resorbed and reaches a new steady state after about 50% of bone loss. This finding agreed with previous clinical studies. Furthermore, results of virtual computations of bone density in a composite femur showed the development of a dense cortical bone around the medullary canal and a dense trabeculae bone between the femoral head and the calcar region of the medial cortex due to compressive stresses. The comparison of the predicted bone density with the structure of the proximal femur obtained from X-rays and using strain energy density gave credibility to the current model.

Hereditary sensory and autonomic neuropathy type IV orthopaedic complications.

Painless fractures with delayed healing or abnormal callus formation require exclusion of a systemic disorder. We report a 9-year-old girl with hereditary sensory and autonomic neuropathy type IV who developed bone changes in the hind foot after a protracted healing of a tibia fracture. Osteomyelitis was considered as a possible cause of destruction of the tarsal bones. Negative sweat test documented anhydrosis. Late diagnosis in our patient occurred because of an unusual clinical course of the disease.

Pachydermoperiostosis-critical analysis with report of five unusual cases.

Pachydermoperiostosis (idiopathic hypertrophic arthropathy) {MIM 167100} is an uncommon disease characterized by unique phenotype (digital clubbing and pachydermia) and distinctive radiographic appearances (periostosis). Two families are reported that, in additional to the typical phenotype and radiographic characteristics of pachydermoperiostosis, show some rare and/or unusual, not yet reported, clinical findings. In the first family, distinctive features were severe progressive arthritis with villonodular involvement of the knees. The clinical course of the disease was much more severe than usually reported. The older brother was disabled at the age of 29 years. In the second family, the clinical history was exceptional, with unique early appearance of clinical signs. Pachydermoperiostosis is usually inherited as a dominant trait, but probable autosomal recessive inheritance has been reported. Also in the present families, autosomal recessive inheritance is likely, possibly explaining the severe clinical course of the disease. Differential diagnosis and the confusing nomenclature of pachydermoperiostosis are discussed.

Familial expansile osteolysis--not exclusively an adult disorder.

Familial expansile osteolysis (FEO, MIM174810) is a rare syndrome which was observed world-wide in only three kinships and in two unrelated American individuals. We report a patient with familial expansile osteolysis from the Czech Republic, not related to the previously reported cases. This patient's extraordinary clinical course does not conform to the ordinary. Her radiographic bone involvement was unusually extensive, involving most of the peripheral skeleton and the skull. This case documents that familial expansile osteolysis is not only a disease of adults but does occur in childhood.

Dominantly inherited progressive pseudorheumatoid dysplasia with hypoplastic toes.

OBJECTIVE: To present four related patients with progressive pseudorheumatoid dysplasia (PPsRD) each with distinctive history, unique phenotype and some peculiar radiographic findings. RESULTS AND CONCLUSIONS: The history was characterised by weather-dependent articular pain. The unique phenotypic features were hypoplasia/dysplasia of one or two toes. Peculiar radiographic findings were hypoplasia of the 3rd and 4th metatarsals, platyspondyly with rectangular shape of the lumbar spinal canal, progressive narrowing of the joint spaces and early synovial chondromatosis. Finally, the condition was inherited as a dominant trait. This constellation of abnormalities constitutes a distinct form of PPsRD. PPsRD must be differentiated from other bone dysplasias, specifically spondyloepiphyseal dysplasias, autosomal dominant spondylarthropathy, juvenile rheumatoid arthritis and osteoarthritis.