Biomedical subjects

Jaro Karppinen

Publications and source records attributed to Jaro Karppinen.

21 records · Page 2Linked to original sources

PubMed2003

Radiologic phenotypes in lumbar MR imaging for a gene defect in the COL9A3 gene of type IX collagen.

PURPOSE: To evaluate whether the COL9A3 tryptophan allele (Trp3 allele) is associated with a specific radiologic phenotype among patients with sciatica. MATERIALS AND METHODS: One hundred fifty-three patients with sciatica were evaluated for the presence of Trp3 allele, Scheuermann disease, intervertebral disk degeneration, Schmorl nodules, dorsal anular tears, hyperintense lesions, and endplate degeneration on sagittal T2-weighted lumbar magnetic resonance images. The Trp3 genotype was determined by means of sequencing the COL9A3 gene. Radiologic phenotypes were evaluated while blinded to the genotype. Scheuermann disease was diagnosed if either endplate irregularities or Schmorl nodules and two of the other three criteria (disk space narrowing, disk dehydration, and wedging of anterior vertebral body margins) were present at three or more adjacent disk levels from T10-11 to L3-4. Disk degeneration was evaluated separately for each disk (T11-12 to L5-S1) and for all disks combined. Frequencies of radiologic phenotypes between individuals with or without Trp3 allele were compared. RESULTS: Thirty-four patients had at least one Trp3 allele. When compared with the matched control subjects, they had an increased likelihood of Scheuermann disease (P =.035) and an increased number of degenerated disks from T11 to S1 (P =.021). Comparisons at individual disks showed a statistically significant increase in disk degeneration at T11-12 (analysis of all grades of degeneration [graded], P =.018; analysis of any degeneration vs none [dichotomous], P =.039) and L4-5 (graded, P =.011; dichotomous, P =.016). Prevalences of anular tears, endplate degeneration, Schmorl nodules, and hyperintense lesions were comparable. CONCLUSION: The results of this study indicate that the presence of Trp3 allele is associated with Scheuermann disease and intervertebral disk degeneration. No associations were found for other radiologic phenotypes.

Collagen Type IX↗

PubMed2002

Gadolinium diethylenetriaminepentaacetic acid enhancement in magnetic resonance imaging in relation to symptoms and signs among sciatic patients: a cross-sectional study.

STUDY DESIGN: A cross-sectional descriptive study. OBJECTIVES: Gadolinium enhancement in lumbar magnetic resonance imaging is not used routinely. The current study explored the possible intercorrelations of enhancement patterns with clinical symptoms and signs. SUMMARY OF BACKGROUND DATA: Rim enhancement has been reported to occur in the periphery of disc herniations, and it is thought to represent neovascularization. To the authors' knowledge, the significance of the enhancement in relation to clinical symptoms has not been studied. METHODS: Magnetic resonance imaging of the lumbar spine with intravenous gadolinium diethylenetriaminepentaacetic acid was performed in each patient. Various contrast enhancement parameters and volume of herniation were evaluated, and their correlations with clinical signs and symptoms (straight leg raising, motor defect, Achilles reflex, leg and back pain, disability) were analyzed. RESULTS: The extent of rim enhancement correlated highly significantly with the degree of disc displacement, being most pronounced in the case of sequesters. The duration of sciatic symptoms correlated negatively with enhancement. The clinical symptoms did not correlate significantly with the different enhancement parameters or disc herniation volume. Straight leg raising correlated only slightly with the extent of rim enhancement (P = 0.04) when bulges were excluded. Achilles reflex abnormality correlated significantly with all enhancement parameters for lesions at L5-S1. In the final stepwise logistic regression model, contrast enhancement extent correlated most significantly with abnormal Achilles reflex (P = 0.0002). CONCLUSIONS: Although rim enhancement of disc herniation is thought to represent a beneficial phagocytotic phenomenon, it may also have a harmful effect on the adjacent nerve root.

Achilles Tendon↗

PubMed2002

Magnetic resonance imaging findings in relation to the COL9A2 tryptophan allele among patients with sciatica.

STUDY DESIGN: The phenotype of patients with sciatica who have the Trp2 allele is characterized cross-sectionally. OBJECTIVE: To determine whether it is possible to differentiate patients with the Trp2 allele clinically or by magnetic resonance imaging. SUMMARY OF BACKGROUND DATA: Several studies have indicated a positive family history for intervertebral disc disease. Previously, a dominantly inherited defect was identified in the COL9A2 gene that changed a codon for glutamine to that for tryptophan in the alpha2 chain of collagen IX (Trp2 allele). This change may render intervertebral discs more fragile. METHODS: Clinical findings, clinical symptoms, and magnetic resonance imaging (1.5-T) findings from 159 patients with sciatica were evaluated according to the presence of the Trp2 allele. Additionally, the magnetic resonance imaging scans of 22 family members from three families were evaluated. These scans were analyzed intervertebral disc and endplate degeneration, Schmorl's nodes, transverse tears (hyperintensity in the region of Sharpey's fibers), high-intensity zone lesions (bright spots in the dorsal anulus), and radial tears (hyperintense linear area from the nucleus to the outer part of the anulus on T2 sequences). RESULTS: Six patients with sciatica and 11 family members had the Trp2 allele. No homozygotes were found. Clinical symptoms of patients with and those without the Trp2 allele were similar. Patients with sciatica who had the Trp2 allele were significantly more flexible (P < 0.05), according to the modified Schober measure. The disc and endplate degeneration in 6 patients with the Trp2 allele and their 18 controls (matched for age, occupation, gender) without the allele did not differ significantly, whereas family members with the Trp2 allele had a greater degree of disc and endplate degeneration at L5-S1. The overall prevalence of endplate degeneration was high in this study. The prevalences of dorsal transverse tears, high-intensity zone lesions, and Schmorl's nodes did not differ among patients with sciatica or family members according to the presence of the Trp2 allele. There was, however, a trend for increased prevalence of radial tears in nonherniated discs among the Trp2 allele-positive subjects (3 of 6 patients with sciatica and 3 of 11 family members), as compared with the Trp2-negatives subjects (none of 18 "matched" patients or 11 family members). CONCLUSION: The patients with the Trp2 allele were more flexible, and more often tended to have a radial tear in a nonherniated disc than their control counterparts.

Adult↗