Jie Meng, Presenter: Nothing to Disclose

Michel De Maeseneer MD, Abstract Co-Author: Nothing to Disclose

Stijn Vantieghem, Abstract Co-Author: Nothing to Disclose

Johan De Mey, Abstract Co-Author: Research grant, General Electric Company

Maryam Shahabpour MD, Abstract Co-Author: Nothing to Disclose

To assess the significance as well as prevalence and prominence in different age groups of the lateral bony ridges on the palmar aspect of the proximal and middle phalanx of the 2nd through 4th finger.

We reviewed  130 oblique radiographs of the hand randomly selected from PACS and evenly distributed over 8 age groups (n= 15 for each group). Skeletal specimens consisting of full mounted hands (n=9) from elderly patients were studied.  The ridges were evaluated on all images and specimens by consensus of 2 readers using a 4 point scale (0, none; 1, small; 2,medium; 3,prominent).  Regression analysis was performed. The technique of  ultrasound during progressive dissection  was performed  in cadaver specimens (n=5) to study the relationship of tendons, sheaths, and pulleys, with the ridges.

The ages of  patients from the radiographs was evenly distributed from birth to over 70 years. For all fingers and for both proximal and middle phalanx there was a statistically significant correlation between the prominence of the ridges and age (p< 0.005).  For the proximal phalanx the ridges at the level of the 4th finger were more prominent at all ages, followed by the 3th, and 2nd and 5th finger. For the middle phalanx the ridges were more prominent at all ages for the 3th and 4th finger, followed by the 2nd and 5th finger. Ridges at the proximal phalanx were not seen before age 20, and mean grading  reached 1 at  age 40 but only for the 4th finger.  Ridges at the middle phalanx were present from the 10-20 age group on, only in the 3th and 4th finger. The mean grading also reached above 1 from 40 years on for the 3th and 4th finger. In the bony specimens all mean gradings were higher than 1.4. Anatomical investigations showed that the ridges of the proximal phalanx corresponded to the insertion site of the A2 pulley, and the ridges at the middle phalanx to the insertion site of the flexor superficialis tendon.  

Bony ridges can be observed at the proximal and middle phalanx of the 2nd through 4th finger and  respectively correspond to the insertion of the A2 pulley and the flexor superficialis tendons. The ridges at the proximal phalanx are not present before age 20, and  remain small untill age 40. The ridges at the middle phalanx are observed earlier.

Rise awarenes of the presence and anatomical significance of normal ridges and the age at which they occur at the proximal and middle phalanx.

Meng, J, De Maeseneer, M, Vantieghem, S, De Mey, J, Shahabpour, M, Prevalence, Correlation with Age, and Anatomical Significance of the Palmar Bony Ridges of the Phalanges: Imaging and Anatomical Investigation.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12032347.html