What’s Important: Science, Faith, and Grace
From the outset, Doug had faith that thoughtful investigation could improve our understanding of the workings of the shoulder, and could lead to practical ways of addressing the problems that prevented patients from enjoying their lives. His studies of anatomy and biomechanics enabled him to ask basic but often-overlooked questions, such as, “How does such a shallow glenoid socket stabilize such a big humeral head through a huge variety of activities, ranging from ballet to weight lifting?”
This question led Doug to conduct foundational cadaveric research on the stabilization and movement of the shoulder joint. He recognized that the motions of the shoulder could not be accurately determined from observing the outside of the arm, but required that motion sensors that were rigidly fixed to pins be drilled into the bones of the humerus and the scapula. Using this technique with cadavers, he addressed the paradox of how the shoulder can be lax and stable at the same time by showing that the shoulder’s primary stabilizing mechanism was not ligamentous restraint (the prevailing thought at the time), but rather dynamic compression of the humeral head into the glenoid concavity, which functioned throughout the joint’s range of motion. His concept of “concavity compression” transformed our approach to the management of patients with shoulder instability.
Wanting to be sure that his observations did not apply only to cadavers, Doug enlisted the collaboration of 6 colleague orthopaedists, now known as the “pin brothers,” who allowed motion sensors that had been attached to Steinmann pins to be drilled into the humerus and the scapula to accurately define their positions and rotations during activities of daily living, ranging from tucking in a shirt to doing pushups. Of course, Doug insisted on being the first to be drilled, securing his position as the “first among the pin brothers.”
These novel in vivo studies confirmed that normally functioning shoulders are lax (i.e., the humeral head passively translates on the face of the glenoid when the surrounding muscles are relaxed), but are simultaneously stable (i.e., the humeral head does not translate when the surrounding muscles are contracted, pressing the ball into the socket). Doug assembled his findings in an engaging series of videos that he generously shared with the world (http://shoulderarthritis.blogspot.com/2016/09/how-shoulder-works-videos-by-late-doug.html). His recognition that a shoulder could be both lax and stable at the same time fundamentally altered our surgical approach to restoring shoulder mobility and stability.
Doug was also a recognized pioneer in shoulder arthroscopy. He loved exploring shoulder pathoanatomy through what he called a “room with a view.” I was often invited to witness his latest discoveries and to see his creative attempts to manage shoulder problems with arthroscopic guidance. His methods for arthroscopic labral repair, rotator cuff repair, and capsular release of the stiff shoulder are recognized as important surgical advances to this day.
Doug pioneered the development of the Simple Shoulder Test (SST) by recording the most common symptoms of individuals presenting with shoulder problems. To validate the SST in normal subjects and in those with cuff tears, he turned to the members of his church for volunteers. This congregational cohort provided the foundation for what has become one of the most widely used patient-reported outcome tools in the world today.