What should you know about patellar tendon rupture after total knee replacement?

A patellar tendon rupture after total knee replacement can disrupt knee straightening and requires prompt orthopaedic assessment. The tendon connects the kneecap to the shinbone and works with the thigh muscles to extend the knee. A tear may cause a sudden loss of active straightening, a low or altered kneecap position, swelling, bruising, or difficulty walking.

After a knee replacement, the tendon may be vulnerable because the joint has undergone major surgery and the tissues are healing. A fall, forceful movement, wound problem, or gradual weakening may contribute. The artificial joint does not itself make every new symptom a rupture; examination is needed to distinguish tendon failure from stiffness, pain, or another postoperative problem.

The clinician may check the gap or tendon contour, your ability to lift the straight leg, knee alignment, and the stability of the replacement. X-rays can show kneecap position, while ultrasound or magnetic resonance imaging may help examine soft tissue when appropriate.

Contact the orthopaedic team promptly if you suddenly cannot straighten the knee, the leg gives way, or swelling follows a fall. Use the brace or walking aid exactly as instructed and avoid forceful bending until reviewed. Tendon Repair Surgery may be considered for a complete tear; the plan depends on tissue quality, timing, the implant, and other injuries. Rehabilitation follows a protected progression.

Post-Operative Rehabilitation can help restore controlled movement, strength, balance, and walking after the treating team has protected the repair. Progression is usually staged rather than based on pain alone.

Seek urgent assessment after a fall or sudden pop with loss of straightening, marked swelling, wound opening, drainage, fever, or severe calf pain. Call emergency services for chest pain, sudden breathlessness, fainting, or a cold, pale, numb foot. These symptoms may indicate a serious postoperative or circulation problem requiring immediate attention.

Ask whether the tendon appears partly or completely torn, which imaging is useful, and whether the replacement is stable. Discuss bracing, weight-bearing limits, the timing and goals of Tendon Repair Surgery if needed, and how Post-Operative Rehabilitation will protect the repair while strength returns.