Posterior translation of the fibula may indicate malreduction: CT study of normal variation in uninjured ankles.

OBJECTIVES: The aim of our study was to assess the intersubject and intrasubject variations of distal tibiofibular syndesmosis on computed tomography (CT) scans and to define standardized measures to verify syndesmosis reduction. DESIGN: A retrospective study of 107 CT scans of ankles with normal tibiofibular syndesmosis. SETTING: Main trauma center, university teaching hospital. PATIENTS: The CT scans of 64 patients were reviewed by 2 musculoskeletal radiologists. MAIN OUTCOME MEASUREMENTS: Bilateral variation was estimated. The intra- and interobserver reliabilities were calculated using standardized measurement points. CT measurements included the length of the tibial incisura (LI), A width and P width of the incisura (PW), depth of the incisura, narrowest part of the incisura, and sagittal translation of the fibula. RESULTS: In 97% of normal cases, the fibula is situated either centrally or anteriorly in the tibial incisura. There were significant differences in PW and LI between genders, and the difference between the PW and A width was significantly larger in males (2.7 mm, SD 2.1) than in females (1.9 mm, SD 1.6, P = 0.023, t test). Significant asymmetry was not detected between ankles in single subjects. All CT measurements demonstrated good inter- and intraobserver reliabilities. CONCLUSIONS: If P translation of the fibula is present, malreduction should be considered. Sagittal translation measurements are not affected by the size of the joint or the gender of the patient, in contrast to traditionally used cross-sectional measurement methods.

Genetic susceptibility of intervertebral disc degeneration among young Finnish adults.

BACKGROUND: Disc degeneration (DD) is a common condition that progresses with aging. Although the events leading to DD are not well understood, a significant genetic influence has been found. This study was undertaken to assess the association between relevant candidate gene polymorphisms and moderate DD in a well-defined and characterized cohort of young adults. Focusing on young age can be valuable in determining genetic predisposition to DD. METHODS: We investigated the associations of existing candidate genes for DD among 538 young adults with a mean age of 19 belonging to the 1986 Northern Finland Birth Cohort. Nineteen single nucleotide polymorphisms (SNP) in 16 genes were genotyped. We evaluated lumbar DD using the modified Pfirrmann classification and a 1.5-T magnetic resonance scanner for imaging. RESULTS: Of the 538 individuals studied, 46% had no degeneration, while 54% had DD and 51% of these had moderate DD. The risk of DD was significantly higher in subjects with an allele G of IL6 SNPs rs1800795 (OR 1.45, 95% CI 1.07-1.96) and rs1800797 (OR 1.37, 95% CI 1.02-1.85) in the additive inheritance model. The role of IL6 was further supported by the haplotype analysis, which resulted in an association between the GGG haplotype (SNPs rs1800797, rs1800796 and rs1800795) and DD with an OR of 1.51 (95% CI 1.11-2.04). In addition, we observed an association between DD and two other polymorphisms, SKT rs16924573 (OR 0.27 95% CI 0.07-0.96) and CILP rs2073711 in women (OR 2.04, 95% CI 1.07-3.89). CONCLUSION: Our results indicate that IL6, SKT and CILP are involved in the etiology of DD among young adults.