A tendon is a tough, flexible band of fibrous connective tissue connecting muscle and bone. When a tendon suffers a full rupture, the ability to move the connected joint is lost, requiring intervention to restore function. How long one can wait before repairing a ruptured tendon is a critical consideration, depending on biological and mechanical factors unique to the injury.
The Critical Window for Acute Tendon Repair
The optimal time frame for surgical repair of a fully ruptured tendon is generally within the acute phase, which typically spans the first one to three weeks following the injury. Operating during this period is preferred because the two torn ends of the tendon have not yet significantly separated or degraded. The tissue quality remains relatively healthy, allowing for a primary repair where the surgeon can directly stitch the ends back together with minimal tension.
For high-demand tendons, such as the Achilles tendon, the window is often narrower, ideally within the first two weeks. Delaying beyond this point increases the technical difficulty of the procedure and negatively affects the final functional outcome. Early intervention aims to restore the original length and tension of the muscle-tendon unit.
Biological Changes Caused by Delay
When a tendon rupture is not repaired promptly, the injury site begins a series of biological changes that complicate later surgery. The most immediate change is tendon retraction, where the muscle attached to the tendon end contracts, pulling the torn segment away from its attachment site. This creates a gap that widens over time, making it impossible to pull the ends together without significant force.
The body’s inflammatory response also leads to dense, disorganized tissue known as fibrosis or scar tissue. This process causes adhesions, where the injured tendon becomes stuck to surrounding structures, such as the tendon sheath or nearby muscles. These adhesions disrupt the smooth, gliding motion necessary for normal joint function, requiring extensive surgical dissection to free the tendon before repair can even begin.
Factors Influencing Repair Urgency
The urgency of repair is influenced by the injury location and the patient’s overall health. High-tension tendons, including the Achilles, quadriceps, and patellar tendons, are under constant, powerful pull from large muscles and retract quickly, demanding a more rapid surgical response. In contrast, some hand flexor tendons may allow for a slightly longer period, though immediate repair is still preferred.
The type of tear is also a major determinant; a complete rupture requires prompt surgical reattachment, while a partial tear may often be managed non-surgically with immobilization and physical therapy. Open injuries, such as lacerations, must be treated as a surgical emergency, often within 24 hours, to clean the wound and prevent infection. Patient factors like smoking, diabetes, or poor nutrition can also significantly impair the healing process, sometimes prompting surgeons to operate sooner to bypass a prolonged inflammatory phase.
Outcomes of Delayed or Chronic Repair
A rupture that is left unrepaired past the acute phase—typically four to six weeks—is classified as a chronic injury, which fundamentally alters the surgical approach and prognosis. By this time, the gap between the tendon ends is often too wide to bridge with a simple suture without creating excessive tension, which would risk the repair failing. Chronic repairs therefore frequently necessitate more complex procedures to restore the connection.
These advanced techniques may involve using a tendon graft harvested from the patient’s body, or performing a tendon transfer, which reroutes a nearby tendon to assume the damaged function. While chronic repairs can restore function for daily activities, they often result in a less robust outcome than acute repair, especially for patients seeking to return to high-level athletic activity. Patients with chronic ruptures may experience permanent loss of muscle strength and a longer recovery due to scar tissue and altered mechanical properties.