We have all heard the term “Cobb angle”, it is used every day. We hear people saying that, my Cobb angle is so and so.. the doctor said that, at this Cobb angle we recommend surgery and so on. We know that Cobb angle is used to measure the spines curvature, but do you know where it comes from?

I certainly did not. Neither did any of my colleagues. And I bet that most orthopedic surgeons don’t know either.

Cobb measures "angle of the curve"

I have managed to get my hands on a unique paper. It is written by Dr John. R. Cobb (yes, Dr Cobb was actually an M.D. in New York) and he wrote a paper [1] in 1948, in which he described the way he was measuring the “angle of the curve” on the x-rays. Dr Cobb believed it was the best way to measure scoliosis curves and I believe many agreed with him then and many still do. It is after all considered the Gold Standard for measuring scoliosis.

1. Cobb, J. R.
Outline for the study of scoliosis. In Instructional Course Lectures, The American Academy of Orthopaedic Surgeons.
(AAOS) Vol. 5, p. 261-75. 1948.