Knee doctor in San Francisco and Santa Barbara
Knee pain can keep you from running, climbing stairs or sleeping well. Dr. Christian Guier, a board-certified orthopedic surgeon with fellowship training in knee surgery, evaluates and treats knee injuries and arthritis.
Common knee problems
ACL tear
The anterior cruciate ligament keeps the knee stable when you pivot or change direction. Tears often happen in skiing, soccer and basketball and can cause a pop, swelling and a feeling that the knee gives way.
Meniscus tear
The menisci are C-shaped cartilage cushions between the thigh bone and shin bone. Tears can come from a twisting injury or from wear over time and may cause pain, swelling, catching or locking.
MCL and other ligament sprains
The medial collateral ligament on the inner side of the knee is often injured by a blow to the outside of the knee or an awkward twist. Many MCL injuries heal without surgery.
Kneecap pain and instability
Pain around or behind the kneecap is common in runners and cyclists. Some people have a kneecap that slips partly or fully out of place.
Knee arthritis
Wear of the cartilage that lines the joint can cause pain, stiffness and swelling, especially during or after activity.
Knee tendon injuries
The patellar and quadriceps tendons help straighten the knee. Overuse can inflame them, and a hard landing or fall can tear them.
When to see an orthopedic surgeon
- A pop at the time of injury, followed by swelling
- A knee that gives way or feels unstable
- Catching, locking, or not being able to fully straighten the knee
- Swelling that doesn't improve after a few days
- Pain that limits walking, stairs or sleep
- Pain that lasts more than a few weeks despite rest
Get emergency care if
You can't put any weight on the leg, the knee looks deformed, the leg below the knee is cold or numb, or the knee is hot, red and swollen with a fever.
Christian A. Guier, MD CM, FAAOS, FACS
How Dr. Guier evaluates your knee
Dr. Guier starts with how the injury happened and what you want to get back to. He examines the knee's motion, stability and tenderness, and orders X-rays or an MRI when the results will change your treatment.
He'll review any X-rays or MRI with you and explain what they show before discussing options.
Non-surgical care
- Activity changes and a short period of rest
- Physical therapy and a home exercise program
- Knee bracing
- Anti-inflammatory medication when appropriate
- Injections when appropriate
When surgery may help
- Arthroscopic knee surgery, including meniscus repair or trimming
- ACL reconstruction
- Ligament repair
- Kneecap stabilization
- Fracture repair
Surgery is usually considered when a knee stays unstable, a tear causes locking, or symptoms don't improve with non-surgical care.
Dr. Guier will walk you through every reasonable option and help you choose what fits your goals.
What patients say
Dr Guier was fantastic - thorough and explained his thoughts and diagnosis really simply and clearly. Highly recommended.
Dr. Guier is excellent, knowledgeable, and kind. I had a wonderful first appointment.
Great service super helpful and clear communication the absolute best I highly recommend!
Knee questions
Get your knee checked.
Request a consultation in San Francisco, Santa Barbara or by video.
This page is for general education and isn't medical advice. For advice about your situation, request a consultation. Last updated September 2026.