A contracture represents a structural change in the body’s soft tissues, causing them to shorten, harden, and resist stretching. This condition leads to a restriction in the passive range of motion of a joint, which can severely limit function and mobility. The stiffening affects non-bony tissues like muscles, tendons, ligaments, and the joint capsule. Reversibility depends on the nature of the tissue changes and how long the condition has been present. This article examines the mechanical causes, the factors that influence reversibility, and the various treatment strategies available, from non-invasive methods to surgical intervention.
Understanding the Mechanics of Contractures
A contracture develops when normally elastic soft tissues are replaced by inelastic, fibrous tissue, a process sometimes referred to as fibrosis or scarring. When a joint is immobilized, changes begin quickly, with muscle fiber shortening occurring within 24 hours. Prolonged disuse or immobility is the most frequent cause, often seen following fractures, extended bed rest, or joint replacement surgery.
Neurological conditions also contribute significantly, as disorders like stroke or cerebral palsy can lead to muscle imbalance and prolonged spasticity. This increased muscle tone can result in joint immobilization, accelerating structural changes in the surrounding soft tissue. Trauma, such as severe burns or deep wounds, also causes a contracture as the resulting scar tissue shrinks and tightens across a joint. The replacement of tissue with a denser, more rigid form ultimately limits the joint’s capacity to move freely.
Key Factors That Determine Reversibility
The potential for a contracture to be reversed is heavily influenced by its duration and the underlying cause. Acute, or newer, contractures, which have not yet undergone extensive fibrous tissue replacement, are significantly more responsive to non-surgical treatment. Conversely, chronic, long-standing contractures involve substantial replacement of elastic fibers with rigid collagen, making them highly resistant to stretching and often requiring more aggressive intervention.
The severity of the initial immobility and the extent of tissue damage also dictate the prognosis. Full spontaneous recovery is usually limited to the least severe contractures. Once the contracture has reached a certain severity, additional time without intervention typically does not lead to further gain in joint mobility.
The specific tissue involved plays a large role, as muscle tissue is more pliable than a severely shortened tendon or a thickened joint capsule. Contractures resulting from temporary immobilization, such as a cast for a broken bone, generally have a better outlook than those stemming from progressive neurological disorders or extensive burn scarring. Scar tissue is most easily shaped in the early stages before it fully matures, which can take up to two years.
Conservative Strategies for Reversal
Conservative management is the first-line treatment for contractures, particularly those of recent onset or milder severity. The goal is to remodel the shortened tissues by holding them in a lengthened position for extended periods, a concept known as low-torque, long-duration stretch. This approach encourages the gradual elongation of the tissue rather than forceful, damaging stretching.
Physical and occupational therapy are foundational, utilizing active and passive range-of-motion exercises to maintain and slowly increase joint extension. Therapists often use heat and massage techniques to prepare the tissues, increasing their extensibility before stretching begins. Stretching interventions are most effective when sustained, rather than quick movements.
Splinting and orthotics are used to maintain the gains achieved during therapy and to apply a sustained stretch. Static-progressive splints and dynamic orthoses are designed to hold the joint at the end of its available range of motion, maximizing the time the tissue is under tension.
Serial Casting
Serial casting is a highly effective conservative technique where a cast is applied to hold the joint at its maximum corrected position. The cast is then periodically removed, and a new one is applied to capture the incremental improvement in range of motion, gradually correcting the deformity over weeks or months. This method is particularly useful for contractures that have resisted standard splinting and exercise.
Surgical Options for Severe Contractures
When conservative treatments fail to achieve functional improvement, or when the contracture is fixed and severe, surgical intervention becomes necessary. Surgery is typically considered when the loss of motion significantly limits daily activities or causes pain. The type of procedure performed depends on the specific tissues contributing to the restriction.
Tendon lengthening, or tenotomy, is a common procedure that involves cutting or partially releasing a shortened tendon, such as the hamstring tendons or the Achilles tendon. This reduces the mechanical pull that prevents full joint extension. For contractures caused by joint stiffness, a capsular release may be performed, often arthroscopically, to release the thickened joint capsule.
Burn contractures involving significant skin scarring may require specialized procedures like Z-plasty or skin grafting to release the constricted skin envelope. Following surgical correction, patients must immediately begin intensive physical therapy. This post-operative therapy, which often includes a splinting program, is necessary to maintain the newly gained range of motion and prevent recurrence.