No abstract

In a Finnish kindred consisting of 192 descendants from two marriages of a male ancestor born in 1868, the lumbar spines of 105 of the 170 living members were X‐rayed. Spondylolysis was found in 22 individuals. In addition, six of them had spondylolisthesis, four had spina bifida occulta, and two had a transitional lumbar/sacral vertebra. Seven members of the kindred without spondylolysis had spina bifida occulta and 10 had transitional lumbar vertebrae. The pedigree is consistent with autosomal dominant inheritance and incomplete (about 75 %) penetrance for spondylolysis. It raises the question of a common aetiology for several congenital disturbances in the formation of lumbar vertebrae and possibly supports the concept of a variable expressivity of a “spondylolysis gene”.

A method for directly measuring the reduction in diagnostic accuracy incurred by altering original radiographs was applied to evaluate a 35 mm film system. A total of 4,290 readings of 2,145 proved cases were collected. Analysis of the results indicate that the 35 mm system reduced diagnostic accuracy by about 2.3% +/- 2.4% at a 95% confidence level. The same method can be used to evaluate other photographic reduction systems, television displays, enhancement schemes, or even the importance of clinical data in roentgenographic interpretation.

No abstract

Arthrography was assessed in 300 cases of ankle injury to determine its diagnostic information yield and its aid in classifying ankle injuries. No complications occurred as a result of the procedure. In 59 cases, information gained from the procedure was verified at surgery. Arthrography was considered to give valuable information in 85% of the cases of ligament ruptures.