Manipulation under Anesthesia (MUA) is a non-surgical procedure performed to restore movement in a stiff knee joint, typically after surgery like a Total Knee Replacement (TKR). Stiffness is caused by tough, restrictive bands of scar tissue, known as adhesions, which prevent the knee from fully bending or straightening. During the MUA, the patient is placed under anesthesia, allowing the muscles to relax completely. The surgeon then physically moves the knee through a full range of motion, applying controlled force to break apart the limiting adhesions. This intervention is necessary to regain functional mobility when intensive physical therapy alone has failed to loosen the joint.
The Immediate Post-Procedure Experience
Upon waking, patients may feel groggy as the effects of general anesthesia wear off. Since the procedure involves physically tearing scar tissue, the knee will be sore immediately afterward. Pain management is initiated quickly, often involving oral medication or a nerve block administered during the procedure to control discomfort in the first 24 hours.
The knee will likely experience increased swelling and bruising due to the physical manipulation. Applying ice and keeping the leg elevated above heart level are important steps to manage this inflammatory response. Patients are usually discharged home the same day and are encouraged to begin moving the knee lightly before leaving. The focus of the first 48 hours is pain control and reducing swelling to prepare the joint for the intensive rehabilitation that must follow.
The Role of Intensive Physical Therapy
The success of the MUA depends on immediate and aggressive physical therapy (PT) to maintain the range of motion achieved. Scar tissue naturally attempts to re-form following injury, and the window of opportunity to prevent new adhesions from setting is narrow. Therefore, rehabilitation must begin almost immediately, often on the same day or the morning after the procedure.
Therapy protocols typically require high frequency, such as four to five sessions per week initially, combined with a dedicated home exercise program performed multiple times daily. Specific exercises focus on both extension (straightening) and flexion (bending), including heel slides, prone hangs, and quad sets. Some patients may be prescribed a Continuous Passive Motion (CPM) machine to use at home, which gently moves the knee for extended periods to prevent stiffness.
Patients must push beyond discomfort to stretch the newly freed tissues and prevent the joint from stiffening again. This active participation ensures the body lays down new, more flexible tissue rather than the dense, limiting scar tissue that caused the initial problem.
Expected Timeline for Functional Milestones
The first major milestone is the immediate gain in passive range of motion. Within the first two weeks, the focus remains on controlling swelling while consistently working to achieve at least 90 degrees of flexion. This early period is dedicated to solidifying the range of motion gained and activating the quadriceps muscle, which is often inhibited by pain and swelling.
By four to six weeks post-MUA, patients typically transition to more functional activities as pain subsides and strength improves. This is often the timeframe when individuals can reduce reliance on mobility aids (canes or crutches) and safely return to driving, provided they are not taking narcotic pain medication. Most patients experience the greatest functional improvement, allowing them to resume light daily activities like climbing stairs and walking long distances, within three months. Full recovery generally occurs between three and six months, depending on adherence to the rehabilitation plan.
When to Contact Your Medical Team
While some pain, swelling, and bruising are expected after a knee manipulation, certain signs indicate a potential complication requiring immediate medical attention.
You should contact your medical team promptly if you experience:
- Signs of infection, such as a persistent fever, chills, unusual redness, warmth, or pus-like drainage from the surgical site.
- Severe, uncontrolled pain that is not relieved by prescribed medication.
- Signs of nerve compromise, such as numbness, persistent tingling, or foot drop.
- Symptoms of Deep Vein Thrombosis (DVT), including new, increasing pain or tenderness in the calf or thigh, or swelling that does not go down with elevation.
Seek emergency care immediately if you experience sudden chest pain or shortness of breath, as these may be signs of a life-threatening pulmonary embolism.