Chest wall syndromes are definitely a sports related event, obviously not the only cause, but certainly a common one. The following sports have a component of either trunk flexion alone or trunk flexion coupled with axial rotation. The positional stresses and strains that accompany such activities as golf, tennis, baseball, triathlon, mountain biking/cross-country/trail riding, volleyball, football, soccer, rugby, etc., are a common cause of the subluxation complex being initiated by thoracic cage dysfunction.
The pain from the above thoracic cage dysfunctions may not be at the actual location of the segment in question, as pain is referred to a site either proximal or distal to the actual lesion. If the intercostal nerves are involved the pain might be referred secondarily to a traction effect by the intercostal muscles, or by the numerous biochemical mediators liberated by the inflammatory response. The pain in this case would most likely be referred along the space occupied by this intercostal nerve and not above or below that level. If the dysfunction involves the costochondral junction of the ribs 3-5, then the pectoralis minor could be involved as well, with resultant shoulder joint dysfunction and pain secondary to scapulothoracic rhythm abnormalities. The pectoralis major, if involved as a result of intercostal sprains, costochondral, costotranverse, and costosternal dysfunction, could impair the external oblique muscles' ability to function as a prime rotator of the lumbar spine and lumbar spine compensation; pain would be a reasonable consequence.
The first rib has significant motion and therefore is a cause, when dysfunctional, of the initiation of the subluxation complex. The first rib has been estimated to displace approximately 21 mm superiorly, 15 mm anteriorly, and 8-9 mm laterally. When the first rib is fixated the following muscles can be involved; anterior scalene, middle scalene, iliocostalis cervicis, levator costorum, and the sternocleidomastoid indirectly through its attachment on the clavicle. Scalene involvement could cause the coupled motions of the cervical spine to become fixed and painful as well as initiate occiput C-1 pathomechanics to occur. The levator costorum, as result of scalene hypertonicities now places undue stress on the upper thoracic rib cage and now we have a positive feed back loop: anterior structures causing fixations in the posterior structures, and the posterior structures perpetuating the anterior fixations. The pain will be almost anywhere and will be a self-generating mechanism through decreased and mechanoreceptor input, resulting in unchecked nociceptor input and an out of control sympathetic nervous system. This SNS output results in vasoconstriction, reflex muscle spasm, and eventual disuse of the involved structure: a self-perpetuating cycle.
Examination of this area should include joint play motions and soft tissue palpation. The following text books illustrate various ways to examine the anterior chest wall. Many costochondral and costosternal contacts are also shown.
- Musculoskeletal Pain, D. Zohn, MD
- The Musculoskeletal System, J. Mennel, MD
- Atlas of Technique, A. Stoddard, DO
- Orthopedic Medicine, R. Maigne, MD
- Orthopedic Medicine, J. Cyriax, MD (6) Muscle Stretching in Manual Therapy, O. Evjenth (7) Orthopedic Physical Assessment, D. Magee, PhD (8) Modern Manual Therapy, G. Grieve (9) Medical Checklists, Dvorak and Dvorak (10) Manual Medicine, Dvorak and Dvorak (11) Common Vertebral Joint Problems, G. Grieve (12) Manipulation, Traction, and Massage, J. Basmajian, MD (13) Chiropractic Technique Illustrated, G. Greco, DC (14) Strain and Counterstrain, L. Jones, DO (15) Anatomical Adjustive Technique, H. Beatty, DC (16) Spinal Manipulation, J.F. Bourdillon, MD (17) Orthopaedic Physical Therapy, R. Donatelli (18) Principles of Manual Medicine, P. Greenman, DO (19) Functional Soft Tissue Examination, W. Hammer, DC (20) Chiropractic Therapy, M. Gengenbach, DC, editor (21) Physical Examination, L. Arnold, DC (22) Myofascial Pain and Dysfunction, J. Travell, MD (23) Motion Palpation and Chiropractic Technic, L.J. Faye, DC (24) Physical Examination, B. Bates, MD (25) MPI E2 Seminar Notes, MPI
Obviously the anterior chest wall presents many new and interesting possibilities in the differential diagnosis of cervical spine, thoracic spine, and rib cage lesions. These various techniques are touched upon in MPI's Extremities 2 (E2) seminar, and will be expanded significantly in the new E2 seminar for 1995.
Keith Innes, DC
Editor's Note: Dr. Innes will be conducting his next Spine 1 (S1) seminar in San Francisco June 18-19, and his next Extremities 1 (E1) seminar in Raleigh June 25-26. He will also be conducting a Full Spine (FS) seminar July 9-10 with Dr. Terry Elder in Kansas City. You may call 1-800-359-2289 to register.