Back Pain Caused by Rib Malposition

A very common source of upper and mid-back pain is misalignment of the ribs. Some misalignments of the rib-spine articulation can cause severe, sharp stabbing pain between the shoulder blades which can also radiate into the shoulders. Heavy breathing or taking a deep breath will usually cause an increase in pain. These injuries are usually non-traumatic and can last for weeks unless properly treated. The most common treatment includes pain medications and in some severe cases, pain injections. Complementary alternative medicine such as chiropractic, massage therapy, and physical therapy can provide fast relief from these types of injuries using spinal manipulation, stretching, trigger point therapy, and myotherapy. To better understand rib non-traumatic rib injuries you have to understand the anatomy of the thoracic spine and ribcage and how it works naturally. This is a brief overview of the anatomy of the involved area and the causes of rib pain.

What makes the thoracic spine different from other regions is its articulation with the rib cage. The components of the thoracic cage include the menubrium, sternum, xiphoid, and costal cartilages anteriorly, the T1-T12 spinal vertebrae poseriorly, and the ribs connecting them. Normally there are 12 sets of ribs that make up the thoracic cage. The first 7 ribs are known as true ribs or vertebrocostal ribs. These ribs extend anteriorly from the spine and directly attach to the sternum through individual costal cartilages. Ribs 8-10 are referred to as false or vertebrochondral ribs. They extend from the spine and articulate differently to the sternum. Their costal cartilages join to that of the rib above them. These then collectively attach to the inferior portion of the sternum near the xiphoid process. Ribs 11 and 12 are considered free floating vertebral ribs. These ribs extend from the spine and terminate into the posterior abdominal musculature and never articulate with the sternum. The ribs are further classified as typical and atypical ribs. Ribs 3-9 are considered typical due to their design. Each of these ribs has a wedge shaped head with 2 facets. The inferior facet articulates with the superior demifacet of the corresponding vertebra and the superior facet articulates with the inferior demifacet of the vertebral body above. The crest between the two facets articulates with the interposed intervertebral disc and is connected by an intraarticular ligament. Each costovertebral joint has a capsule that surrounds it and contains articular cartilage and synovial lining. On the anterior side, the capsule is reinforced by the radiate ligament. The radiate ligament extends from the anterior aspect of the rib head to the two articulating vertebral bodies. Ribs 1,2,10,11,and 12 are classified as atypical. They are different from the above described ribs as follows.

The 1st rib is the broadest and shortest of the true ribs. It only has one facet on its head which articulates with the T1 vertebra. It also has a scalene tubercle and 2 grooves for the subclavian artery and vein. The 2nd rib has 2 facets like typical ribs but also has a tubercle for muscle attachment. The 10th and 11th ribs have only one facet like the 1st and the 11th and 12th ribs are short and have no necks or tubercles. The thoracic spine and rib cage are intimately related to the vessels and nerves of the region. The mixed spinal nerves in the thoracic region split and form dorsal and ventral rami. The dorsal ramus passes through the foramen of Cruveilhier and then divides into medial and lateral branches. The inferior aspect of this foramen is the rib below and the lateral aspect is the superior costotransverse ligament. The ventral rami go on to form intercostals nerves and a subcostal nerve at T12. The intercostals nerves travel laterally along the subcostal grooves, just inferior to the intercostals veins and arteries. Each nerve provides motor, sensory, and sympathetic innervation to the thoracic wall. Intercostal muscles lay within the intercostals spaces. There are three layers to this muscle system. The external intercostals muscles form the superficial layer. These muscles run inferoanteriorly between the ribs and aid in inspiration. The internal intercostals muscles are the middle layer and run at right angles to the external intercostals. These muscles aid in expiration. The innermost intercostal muscles are deepest and also aid in expiration. The intercostals nerves and vessels run between the middle and deep layer of the intercostals muscles. Also involved in such cases is the trapezius muscle. It is a large superficial muscle of the neck and back. Due to its attachments into the thoracic spine it can indirectly alter biomechanics of rib articulations and cause instability in the scapulothoracic region. It attaches to the medial 1/3 of the superior nuchal line, EOP, ligamentum nuchae, and the spinal processes of C7-T12. Inferiorly it attaches to the lateral 1/3 of the clavicle, acromion, and spine of the scapula. The superior fibers elevate the scapula. The middle fibers work to retract the scapula. And the inferior fibers depress the scapula.

Pain arising from rib misalignments, also known as subluxations, can be extremely painful in many cases. This atypical chest wall and interscapular pain can raise concern for more serious pathology including cardiac and pulmonary related disease and must be investigated and ruled out in many situations. A number of factors can lead to this sort of pain perception. One of the primary reasons for this is the extensive innervation present at the costovertebral joints. Any abnormal positioning of the rib itself can cause irritation to any number of nociceptive fibers in the area. Because of its central location, lesions in this area can gain access to both spinal and autonomic nerve fibers. Many patients suffering from rib pain can also have symptoms related to the sympathetic nervous system including tachycardia and excessive sweating. These symptoms also mimic more serious visceral pathology. Researchers have recently identified the presence of free nerve endings within the costovertebral and costotransverse joint capsules that respond to inflammation and mechanoreception. This can serves as a primary pain generator but also tells us that these joints can respond well to manipulation. Recent research even points to highly innervated synovial folds within the costovertebral joints as a large player in rib related pain patterns. Another source of pain generation in the thoracic cage comes from motor reflexes coming from the spinal cord. It is well documented that pain afferentation from nociceptive receptors within the rib capsule can cause a motor reflex resulting in myospasm of related musculature including intercostal muscles, leading to a protective splinting response. This may be a direct result of pain caused by excessive movement of the rib articulations when the rib head is out of position. Constant activation of these receptors leads to a loop of nociceptive afferent input and reflex muscular hypertonus and pain. Typically these mechanoreceptors are unmyelinated free nerve endings that are easily stimulated during rib subluxation. In a way this splinting reflex is useful in that it helps to stabilize the joint but it is also very painful at the same time. As the intercostal muscles begin to spasm they cause serious irritation to the intercostals nerves and vessels that run between the two innermost layers of musculature. Initially this results in intense localized pain paraspinally but can progress to radiation along the affected nerves.