Biomedical subjects

Chia-Hsieh Chang

Publications and source records attributed to Chia-Hsieh Chang.

7 recordsLinked to original sources

PubMed2006

Two novel PHEX mutations in Taiwanese patients with X-linked hypophosphatemic rickets.

BACKGROUND: X-linked hypophosphatemic rickets (XLH) is an X-linked dominant disease characterized by renal phosphate wasting, hypophosphatemia, aberrant vitamin D metabolism, and defective bone mineralization. The disease is caused by mutations in the PHEX gene (phosphate-regulating gene with homologies to endopeptidases on the X-chromosome) located at Xp22.1. To date, a variety of PHEX mutations have been identified in these patients. METHODS: PCR and direct sequencing was performed for all exons and intron-exon boundaries of the PHEX gene in two XLH families. RESULTS: Two novel mutations, including a missense mutation (L206W) in exon 5 and a frameshift mutation (nucleotide 1826_1830delAAAAG, stop after codon 610) in exon 18 were discovered and the laboratory and radiographic findings for these patients analyzed. CONCLUSIONS: We found that PHEX gene mutations were responsible for XLH in these Taiwanese patients. Additional studies are needed to enhance understanding of the role of PHEX in XLH pathogenesis.

Adult↗

PubMed2006

Progressive coxa vara by eccentric growth tethering in immature pigs.

The present study tested progressive coxa vara by eccentric growth tethering that might be used to correct coxa valga in cerebral palsy. Eight young pigs received screw fixation at inferior portion of right femoral head at age 4 months and were killed at age 7.25 months for bilateral femurs for comparison. The neck-shaft angle at the tethered side was significantly less than that at the control side (129.8 vs. 138.3 degrees , P<0.05). Histological study showed bony bar formation. Eccentric growth tethering by one screw resulted in a reduction of neck-shaft angle by 8.5 degrees and shortening of femoral length by 4%.

Animals↗

PubMed2005

Rush pin fixation versus traction and casting for femoral fracture in children older than seven years.

BACKGROUND: The optimal treatment for femoral fractures in children is controversial. The purpose of this study was to compare the results of Rush pin fixation with those of conservative treatment, and to evaluate the sequels of growth plate injury by internal fixation. METHODS: Eighteen femoral shaft fractures in 17 children who had concomitant head injury or multiple traumas were treated surgically. The mean age at operation was 9 years 3 months (range, 7 years 5 months to 11 years 1 month). One Rush pin was inserted from the tip of the greater trochanter, without reaming, to fix the fracture. Another 20 age-matched children treated by traction and casting were the control subjects. RESULTS: All the fractures united without consequences. In addition to a decrease in hospital stay with the use of the Rush pin (10 days vs. 27 days, p<0.05), fewer leg length discrepancies (4.2 mm vs. 7.1 mm, p<0.05) were also noted, compared with conservative treatment. The growth of the proximal femur after Rush pin fixation was evaluated after an average of 59 months. No femur shortening, coxa valgus, or hip dysplasia was noted. CONCLUSIONS: Intramedullary Rush pin fixation for femoral shaft fracture in children older than 7 years is a simple and reliable alternative. One narrow and non-reaming pin inserted from greater trochanter did not demonstrate femoral growth inhibition.

Casts, Surgical↗

PubMed2004

Intervertebral disc herniation in adolescents.

BACKGROUND: The purpose of this study was to review surgery-proven lumbar disc herniation in adolescents with an emphasis on the distinguishing features. METHODS: Twenty-eight adolescents between 14 and 18 years old had lumbar discectomy after conservative treatment for 9 months. Indications for surgery were intractable pain and failure of conservative treatment for more than 6 weeks. Lumbar spine apophyseal ring fracture was found in 10 of the 24 patients (42%) who had computed tomography studies. Seven patients had piecemeal excision of the fractured apophysis together with the discectomy. RESULTS: All but three patients could raise their leg more than 70 degrees after the operation. The latest follow-up was conducted an average of 6.1 years after surgery. Good or excellent results were noted in 93% of the patients. Two patients had follow-up operations for recurrent disc herniation and wound infection. CONCLUSION: Apophyseal ring fracture was a feature in adolescent disc herniation that requires surgical intervention. Early computed tomography study is proposed to detect apophyseal ring lesion, which may lead to failure of conservative treatment. Excision of the fractured ring apophysis is suggested in addition to discectomy when the canal space is occupied.

Adolescent↗

PubMed2002

Longitudinal followup study of ultrasonography in congenital muscular torticollis.

High-resolution ultrasonography was used to examine affected sternocleidomastoid muscles in patients with congenital muscular torticollis at different times. Thirty-one female and 42 male patients were recruited and classified as having one of four types of fibrosis based on the sonograms. Compared with initial assessment, 22 (95.6%) patients with Type I fibrosis and 22 (57.9%) patients with Type II fibrosis had a change in classification at the end of the study. Among the patients with Type I fibrosis, the classification of one patient was changed to Type III fibrosis, the classifications of two patients were changed to normal muscle, and the classifications of the other patients were changed to Type II fibrosis. For patients with Type II fibrosis, the classifications of two patients were changed to Type III fibrosis, the classifications of three patients were changed to Type IV fibrosis, and the classifications of the other patients were changed to normal muscle. No changes in classification of patients with Types III and IV fibrosis occurred during followup. Patients with Type IV fibrosis had a significantly high incidence of surgical intervention. Congenital muscular torticollis is a dynamic disease. Ultrasonography can be valuable in observing the alteration. Aggressive management may be necessary for patients with Type IV fibrosis.

Child↗

PubMed2002

The effect of hyperbaric oxygen therapy on spinal fusion: using the model of posterolateral intertransverse fusion in rabbits.

BACKGROUND: The purpose of this study is to evaluate the facilitating effect of hyperbaric oxygen (HBO) on posterolateral intertransverse fusion using a validated rabbit model. METHODS: Twenty-four male New Zealand rabbits underwent posterolateral intertransverse fusion at L5-L6 with autogenous iliac bone graft. They were evenly divided into two groups: the HBO group and the normal room air (RA) group. Each group had six rabbits killed at 4 weeks and 8 weeks, respectively. The rabbits in the HBO groups were treated with 100% oxygen at 2.5 atm for 2 hours a day. After being killed, all rabbits were subjected to radiographic examination, manual testing, and torsional loading to evaluate the results of spinal fusion. RESULT: Radiographic union of intertransverse fusion areas at 4-week RA, 4-week HBO, 8-week RA, and 8-week HBO were 2 of 12, 7 of 12, 7 of 12, and 10 of 12, respectively. Solid union proven by manual palpation was found to be zero of six, three of six, four of six, and five of six of the cases, respectively. The average peak torsional momentums were 2120.2, 2576.5, 2661.6, and 3079.8 N-mm, respectively. Spinal fusion was significantly improved in the HBO groups at both 4 weeks and 8 weeks. CONCLUSION: The results of this study suggest that intermittent hyperbaric oxygen therapy will hasten the bone healing process and improve the fusion rate as compared with the non-HBO group.

Animals↗

PubMedDate not supplied

Extension splint for trigger thumb in children.

Sixty-two reducible trigger thumbs in 50 children with age from 0 to 4 years (mean, 1 year 11 months) were reviewed to study the effect of splinting. Thirty-one thumbs in 24 children received splinting for a mean of 11.7 weeks. The other 31 thumbs in 26 children were only observed. The results were categorized as cured, improved, or nonimproved. Follow-up was conducted after a mean of 20 months (age, 43 months). Result in the splinted group showed cured in 12 thumbs, improved in 10 thumbs, and nonimproved in 9 thumbs, whereas in the observed group, result showed 4, 3, and 24, respectively. Splinting results in 71% trigger thumbs cured or improved that is better than observation alone. The subsequent surgical release for the nonimproved trigger thumbs after splinting still had excellent results. Because surgical release for trigger thumb is not urgent, we suggest extension splinting to be a treatment option before the elective surgery.

Child, Preschool↗