The Achilles tendon, the largest tendon in the body, connects the calf muscles to the heel bone and is susceptible to chronic issues from repetitive strain. Platelet-Rich Plasma (PRP) injection is a treatment designed to stimulate the body’s natural healing processes for these chronic tendon problems. This therapy involves drawing a small amount of a patient’s own blood and processing it to create a solution with a high concentration of platelets. These platelets contain numerous growth factors, which are then injected directly into the damaged tissue to initiate a regenerative response. Understanding the recovery phases after this procedure is important for achieving the best possible outcome.
Managing Acute Symptoms Immediately Following Injection
The initial phase immediately following a PRP injection focuses on managing the controlled inflammatory response initiated by the treatment. It is common to experience increased soreness, mild swelling, and possibly some bruising at the injection site for the first 48 to 72 hours. This discomfort occurs as the concentrated platelets begin to release their healing factors and is often most noticeable during this initial period.
Managing this pain requires a specific approach to avoid compromising the regenerative process. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), such as ibuprofen, naproxen, or aspirin, must be avoided for at least two weeks following the injection, and often for longer. These medications inhibit the enzymes necessary for platelet function and the release of the growth factors that PRP relies on. Instead, patients are encouraged to use acetaminophen (Tylenol) for pain relief, as it does not interfere with the platelet activity.
During these first few days, relative rest is advised to protect the newly treated tissue. Your physician may recommend a period of limited weight-bearing, sometimes involving the use of crutches or a walking boot, depending on the severity of the original tendon issue and the specific protocol used. Applying ice to the treated area for short intervals, such as 15 to 20 minutes a few times a day, can help manage swelling. However, some protocols suggest avoiding ice for the first 48 to 72 hours to allow the full inflammatory cascade to begin.
Phased Return to Activity and Rehabilitation
After the initial acute phase subsides, usually around day three, the focus shifts to a structured, gradual progression of movement and loading on the Achilles tendon. This transition often begins with gentle active range of motion exercises for the ankle, which encourage circulation without placing excessive stress on the treated tendon. Weight-bearing may be slowly increased as tolerated, following the specific guidance provided by the treating physician.
The successful outcome of PRP therapy relies on a dedicated physical therapy program. Physical therapy is a required component that guides the tendon through the process of structural remodeling and strengthening. The rehabilitation program introduces controlled mechanical stress, which is necessary to encourage the healing tendon fibers to align correctly and regain tensile strength.
Achilles tendon rehabilitation incorporates progressive eccentric loading exercises. These exercises involve lengthening the calf muscle while it is under tension, improving the tendon’s ability to tolerate stress. The physical therapist supervises the progression from non-weight-bearing exercises, such as isometrics, to light resistance, and then to full weight-bearing drills. Prematurely returning to high-impact activities like running or jumping must be avoided, as the tendon is still undergoing internal healing and is vulnerable to re-injury.
Expected Timeline for Therapeutic Outcome
The time it takes to experience the benefits of PRP reflects the slow nature of tissue regeneration. Patients should anticipate a lag period, as the initial inflammatory response can cause heightened discomfort, and the biological repair process does not yield immediate pain relief. It is normal to feel no significant improvement, or even slightly worse, for the first four to six weeks following the injection.
Noticeable therapeutic improvement typically occurs around four to eight weeks post-injection, as the growth factors complete their initial signaling and the proliferation phase of healing is underway. During this window, patients may begin to observe a gradual decrease in pain and an improvement in functional capacity, allowing for easier movement and activity.
The maximum benefit from the PRP injection is generally reported between three and six months after the procedure. This extended timeline reflects the time required for the body to fully remodel the damaged tissue, establishing a more robust and resilient tendon structure. If a patient sees no substantial change in symptoms after approximately eight weeks, or by three to four months, a follow-up consultation is appropriate to review progress and discuss adjustments to the rehabilitation plan.