A Brief History of the Anteroposterior Open-Mouth Radiograph

Results 

A search in JAMA Letters sections in the 6 months of issues that followed Dr. Goodley's published letter showed that no one challenged the claim that chiropractors originated the AP open-mouth radiograph. After locating and asking Dr. Goodley about his claim made in JAMA, he replied that he obtained his information from a physiotherapist in Europe. The author located the physiotherapist, who replied that he believed B.J. Palmer originated the view. He recommended a text, in German, titled Atlas und Axis, by Lars Sandberg, DC,4 which he said might provide documentation for the claim.

Two of the author's German-speaking students were unable to find any mention of who originated the AP open-mouth procedure in Dr Sandberg's4 book. It is also possible that this is the same Dr Sandberg who is cited in at least 2 German medical publications: an article titled “Chiropractic diagnosis of the atlanto-occipital joint with reference to the Palmer-Sandberg-Gutman functional aspects from the traditional medic-radiologic viewpoint”5 and another titled “Palmer-Sandberg-Gutmann chiropractic diagnosis of the atlanto-occipital joint from the conventional medical and radiologic viewpoints.”6

The continued search for the origin of the regular (jaw not moving) AP open-mouth view was directed toward a Palmer "green book" book titled Chiropractic Spinography by Dr. E.A. Thompson. 7This 1919 text shows pictures of AP open-mouth radiographs (Fig 3). Case studies that used the AP open-mouth view are also shown in B.J. Palmer's 1934 green book, The Subluxation Specific, The Adjustment Specific.8

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Fig 3. Possibly the first published account of an actual AP open-mouth radiograph. Reprinted with permission from Palmer College of Chiropractic Archives.7(p94)

Further inquiry included MEDLINE searches and telephone calls to the National Library of Medicine, the Medical University of South Carolina (Charleston), and the University of South Carolina (Columbia) medical libraries, all of which did not reveal additional information.

A local telephone call was also made to a radiograph instructor at Spartanburg (South Carolina) Technical College. This inquiry proved to be the most helpful. The suggestion was made to check Merrill's radiograph book by Ballinger and Frank, in Merill's radiograph text,9 background references given for the AP open-mouth radiograph include a 1910 German book10 and a 1919 medical journal from the United States.11 The 1919 article described the AP view taken as follows: “The mouth is opened to its greatest extent, a cork being placed between the teeth to maintain this position…the central ray being centered over the center of the open mouth.”11

The 1910 reference10 cited by Ballinger and Frank9 was requested from the Library of Congress in Washington, DC. The Library of Congress was successful in locating the book and sent its 1906 edition.12 This book was published in the German language and translated by the author's 2 students who speak German. The inside cover of Die Roentgentechnik gives the following credits to Dr Albers-Schonberg as the “Leading Doctor of the X-ray Institute of the General Hospital, St. George–Hamburg.”10

In his 1906 text, Dr Albers-Schonberg10 (Fig 4) described the AP open-mouth procedure: “Sometimes it may be more useful to take the x-ray through the mouth in the supine position since the chin shadow often covers up the upper cervical vertebrae. For this purpose, a piece of cork is placed in between the teeth (in order to keep them apart) and the distal part of the cylinder is positioned right at the opened mouth.”10

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Fig 4. Sketch of Dr Albers-Schonberg, author of Die Rontgentechnik.10 Reprinted with permission from Elsevier.9

This 1906 book most likely excludes chiropractors from being the first to describe the AP open-mouth radiograph because radiography was introduced into the chiropractic profession in 1910.13 However, neither the 1906 text by Albers-Schonberg10 nor the 1919 article in the Boston Medical and Surgical Journal11 provides a picture or sketch of an actual AP open-mouth radiograph. The 1906 edition of Die Roentgentechnik10 shows what appears to be a lower cervical radiographic procedure, but pictures or schematics of an AP open-mouth radiograph were not found in this text. It is possible that the 1910 edition of Die Roentgentechnik10 has a picture of an AP open-mouth radiograph or schematic, but the author was unable to obtain this edition. It is the chiropractic publication from 19197 that shows perhaps the earliest photograph of an actual processed AP open-mouth radiograph (Fig 3).

Discussion and conclusion 

It was admirable of a medical doctor to credit chiropractors for originating the AP open-mouth radiograph, but in view of the evidence presented here, it appears that it is time for the chiropractic profession to return that credit back to a medical doctor, Dr Albers-Schonberg from Germany, for at least providing the first description of the procedure involved in 1906.

The first description of the AP open-mouth radiograph in the United States appears to have been described in 1919 in 2 different publications,7, 11 but only 1 of these, a chiropractic publication,7 provided documentation that the view had been taken. Consequently, chiropractors may have been the first to provide a published photograph of an AP open-mouth radiograph.

Radiologic assessment of the atlas-occiput biomechanics via the AP open-mouth radiograph was described in 193316 and later in 1937,18 and this procedure (atlas-occiput biomechanical assessment via the AP open-mouth radiograph) continues to be primarily a chiropractic procedure.

Understanding the background and history of commonly used procedures may help us better understand what we are using in practice today. It is my hope that other radiographs commonly used by chiropractors will receive similar investigation so their development might also be more fully understood and appreciated.