Voluntary movement begins with a thought. Our brain initiates it by sending a message down the spinal cord to motor neurons that stimulate muscular contraction, which then tugs on bony attachments. But we need our joints to translate that muscle contraction into movement.

The leverage provided by all those hinges, balls-in-sockets, pivots, and gliders turns the impulse to “scratch your nose” into the graceful, effortless, almost spontaneous action that it is. The anatomical term for joint is articulation—it means having things connect in a sequence that works. The same term is used to refer to articulated buses and trains. And it applies to language as well: to be articulate means to be able to string words and ideas together in a chain that makes sense.

Sometimes problems interfere with the sequence of translating force into movement at the points of leverage. This article will focus on three challenges to proper articulation: dislocation, dysplasia, and subluxation.

Anatomy Review: Synovial Joints

Synovial joints are composed of two or more bones with articular cartilage, a synovial membrane, a ligamentous capsule, and varying types and amounts of supporting fascia, ligaments, tendons, and muscles. Some joints have ligaments inside the capsule to tie bones together; others have a supporting structure called a labrum—a cuff of cartilage that helps to support and align the humerus at the shoulder and the femur at the hip. A similar structure can be found in the annular ligament that holds the radius in place as it rotates at the elbow. It is important to point out that while anatomy books show each of these structures as discreet and separate units, in a living body they are completely intertwined and blended through a three-dimensional matrix of connective tissues.

Correct alignment is crucial for synovial joints to work effectively. When the bones in a joint are not in their optimal relationship, joint function is impaired at best and lost altogether at worst: range of motion, weight-bearing capacity, and pain-free, efficient movement is at risk. This can happen because of specific trauma, because of a congenital problem with the shape of the bones, or as a slowly progressive or chronic problem of instability without full dislocation.

Dislocation

A dislocation is a situation in which all joint integrity has been lost: the articulating surfaces are not in contact, and movement that uses the joint as a leverage point cannot happen. Most primary dislocations are the result of trauma, ranging from jamming a finger on a basketball to shattering the acetabulum in a motor vehicle accident. Dislocations are most common at the shallowest joints: the glenohumeral joint, the metacarpal-phalangeal joints, and the patella, which can slip out of the groove defined by the condyles of the femur.

Obviously, a major dislocation is unlikely to happen without extensive damage to other tissues as well. The joint capsule and synovial lining can be stretched; supporting ligaments sprained or ruptured; nearby tendons and muscles may be torn; and nerves, blood vessels, bursae, and other structures may also be compromised. All this makes the healing process complicated, as scar tissue can penetrate multiple structures, severely limiting both range and ease of motion. This is why it is essential to heal in movement: joints should be used, within pain tolerance, as soon, and as fully, as possible after the acute stage of inflammation has passed. This helps new collagen fibers, which knit damaged structures back together, to lay down in alignment with the directions of force instead of in a knotted-up jumble.

The ligaments around joints are strong, but they have poor rebound capacity. This means that once they have been stretched by trauma, the joints they are meant to protect have an increased risk of repeat events with much less force. These spontaneous dislocations can be reduced, or put back into alignment, without much force as well, but they indicate lack of stability, which significantly raises the risk for osteoarthritis at the affected joints. In addition, the muscles that cross the affected joints may become hypertonic as they attempt to stabilize the nearby structures. This can lead to pain, trigger points, and limited range of motion.

Congenital Dysplasia

The acetabulum of a newborn baby is naturally shallow. It slowly closes in around the head of the femur as the infant grows and begins to crawl. Sometimes, however, the contours of the acetabulum don’t correlate to the femur, or the femoral head is misshapen. Either way, the hip socket doesn’t work and the femur can easily subluxate or dislocate. This situation is called congenital dysplasia.

Hip dysplasia can be identified early in infancy. If it affects only one side, the consequences are especially serious: unequal leg length and significant problems with walking are inevitable. Interestingly, if the dysplasia is bilateral, the consequences are much less obvious. While the risk of subluxation or dislocation are still high, it is possible to delay or avoid surgery altogether to correct this situation.

Subluxation

In a subluxation, bones are out of optimal alignment, but the joint capsule is intact. The joint is functional, but it lacks a full range of motion. This can occur when a joint is jarred or has a minor injury, but it is frequently not tied to any specific event.

Joints that commonly subluxate include the intervertebral facet joints, the patellofemoral joint, and the radial head when it slips out of the annular ligament; a subluxation here is sometimes called nursemaid’s elbow, because it is associated with dangling a child by his or her forearm.

Subluxations can be painful, but often—especially at the spine—they involve low-level dysfunction that is chronic and progressive. When they occur at the vertebrae (this is sometimes referred to as vertebral subluxation complex), experts suggest that in addition to interfering with freedom of movement, the displacement can also put mechanical tension on nerve roots and dura mater, leading to referred pain and other symptoms, or poor function in the extremities and viscera. Many of the operating principles of chiropractic and osteopathic medicine point to improved spinal alignment and subsequent efficiency of nerve transmission that occur when the vertebrae are in the best possible relationships to each other. It is worth pointing out that the issue of vertebral subluxations and their relationship to pain and dysfunction is still a topic of heated controversy among many experts.

Treatment

Treatment for joint disruptions depends on the cause. Ligament laxity that contributes to frequent subluxations and a risk of eventual osteoarthritis may be treated with injections of chemicals that promote the growth of fresh collagen to tighten stretched-out structures. This is called proliferant therapy or prolotherapy. Traumatic situations that involve other tissue damage may call for surgery. If the joint capsule and supporting tissues are severely compromised, a surgeon may work to tighten the ligaments to return the joint to its pre-injury status. Closed injuries and small-scale subluxations are usually reducible through manipulation and traction of the affected joint. Chronic and congenital situations may be treated with splints, braces, physical therapy, and exercise to strengthen the muscles surrounding the compromised structures. 

Massage?

Obviously the role of massage and bodywork for a person with any type of joint disruption depends on the severity and stage of the condition. New, acute, and traumatic situations may call for a visit to the emergency room before they call for the work of a massage therapist, but even with an acute injury, a therapist skilled in lymphatic work may be able to help reduce inflammation as long as no risk of infection is present.

In subacute or chronic conditions, massage can have several useful applications. Inevitably, whether a weakened joint is in the upper or lower extremity, compensation patterns emerge as we protect that part of the body from unnecessary stress. These patterns can include postural distortions, twisting, limping, or other alterations to gait, and they can be the source of as much, or more, pain than the initial problem. And, because the joints in the rest of the body are likely to be strong and healthy, rigorous massage to address compensation patterns is safe and appropriate.

Muscles around weak joints tend to become hypertonic in order to function as stabilizers. This can be useful in the short term, but can become problematic if the proprioceptors come to accept this new level of tightness as “normal”—when the joint is ready to bear weight, the muscles may no longer be able to reduce their tightness.

Finally, when inefficient muscle tightness occurs at the spine, it is more difficult for a chiropractic or osteopathic manipulation to be successful, and harder for that adjustment to hold: ingrained muscle tension tends to pull the vertebrae back into subluxation. Massage can address both of these problems by easing tension before an adjustment and helping to reset tension levels afterward. 

Ruth Werner is president of the Massage Therapy Foundation. She is a writer and NCBTMB-approved provider of continuing education. She wrote A Massage Therapist’s Guide to Pathology (Lippincott Williams & Wilkins, 2009), now in its fourth edition, which is used in massage schools worldwide. Her latest book, Disease Handbook for Massage Therapists (Lippincott Williams & Wilkins, 2009), is also available at www.lww.com. Werner can be reached at www.rutherwerner.com or wernerworkshops@ruthwerner.com.