Kneecap Instability Surgery (MPFL)
MPFL repair or reconstruction and related kneecap procedures with Dr. Steven Ward in Tucson and Oro Valley — for a kneecap that keeps sliding out of its groove.
Call 520-881-1394Typical ranges for general education. Dr. Ward’s plan for you may differ.
What it treats
The kneecap (patella) glides in a groove at the end of the femur. The medial patellofemoral ligament (MPFL) on the inner side of the knee keeps it from sliding outward, and it is usually torn when the kneecap dislocates.
- Recurrent dislocation or the kneecap partly slipping out
- Apprehension — the feeling that the kneecap is about to shift
- Cartilage damage behind the kneecap (chondromalacia) or loose fragments from a dislocation, causing pain and swelling
- A tight outer (lateral) side that pulls the kneecap off track
Anatomy can make instability more likely: a shallow groove, knock-knees, rotation of the femur or tibia, or a patellar tendon that attaches too far to the outside.
Is surgery right for you?
A kneecap that stays out of place needs to be put back (reduced), usually in an emergency room. After a first dislocation, treatment is usually non-operative:
- A brace and a short period of crutches if needed
- Physical therapy to strengthen the thigh muscles; cycling is often part of the program
- A gradual return to normal activities, typically within 1–3 months
Surgery is usually reserved for recurrent instability, very high-risk first dislocations, a kneecap that tracks badly out of position, or a loose piece of cartilage or bone. X-rays and an MRI are typical; a CT scan is sometimes used to check alignment.
How the surgery is done
The operation is tailored to why your kneecap is unstable. It often starts with a brief arthroscopy to check the cartilage and remove loose pieces.
- MPFL repair or reconstruction — the inner restraint is repaired or rebuilt with a tendon graft anchored to the kneecap and femur through small incisions
- Lateral release — loosening tight tissue on the outer side of the kneecap; used selectively, usually together with other procedures rather than on its own
- Cartilage debridement — smoothing damaged cartilage behind the kneecap
- Bone alignment procedures — when bone shape or alignment is the main problem, a procedure to realign the tendon attachment or reshape the groove may be recommended
Why a first dislocation is usually treated without surgery
Many people do well with a brace and strengthening after a first dislocation. Surgery makes more sense when the kneecap keeps dislocating, when a loose fragment needs to be addressed, or when anatomy makes another dislocation very likely. Dr. Ward will review your risk factors with you.
Recovery overview
Typical ranges after MPFL reconstruction. Other procedures change the plan, and Dr. Ward’s plan for you may differ.
Weeks 0–6
- A brace and crutches for the first several weeks, with weight as allowed
- Knee bending is increased gradually
- Quadriceps activation and straight-leg exercises as directed
Weeks 6–12
- Wean off the brace and crutches as strength allows
- Return to normal walking
- Strengthening of the thigh and hip muscles; stationary bike
Months 3–6
- Progress to jogging, then agility and sport-specific drills
- Return to sports typically around 4–6 months, once strength, motion, and confidence are back and you are cleared
- Keep up the strengthening program to help protect the kneecap
When to call the clinic
Call 520-881-1394 if you notice any of the following after surgery or while you are recovering:
- A fever of 101°F or higher, or chills
- Redness spreading around an incision, or drainage that is cloudy, foul-smelling, or keeps soaking the dressing after the first few days
- New or worsening numbness, tingling, or weakness in the leg or foot once the anesthesia has worn off, or a foot that turns pale, blue, or cold
- Pain that is not controlled by your prescribed medication, ice, elevation, and rest
- Pain, swelling, or tenderness in the calf that is new or getting worse
- The kneecap slips out of place again (go to the ER if it stays out)
It is normal for the knee to be swollen, bruised, and sore for a while, and for the leg to feel numb or weak until a nerve block or spinal anesthetic wears off. Use your crutches, walker, or brace as directed. Call if something feels different from what you were told to expect.
for chest pain, shortness of breath, or trouble breathing. These can be signs of a blood clot in the lungs and need emergency care.
If something does not match the instructions you were given, call the office. Dr. Ward or one of his physician assistants will get back to you.
Related resources
Knee arthroscopy & meniscus resection
Dr. Ward’s knee arthroscopy page, including his meniscus resection rehab protocol.
Open pageKnee post-op hub
Knee arthroscopy and knee replacement packets, rehab protocols, and anatomy guides.
Open pageExercise guides
Printable home exercise programs to use with your physical therapist.
Open pagePhysical therapy locations
Find a physical therapy clinic near you in Tucson and Oro Valley.
Open pageOrthoInfo: Unstable kneecap
Patient education on patellar instability from the American Academy of Orthopaedic Surgeons.
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