Knee Giving Out When Bending
Your knee may look like a simple structure from the outside, but on the inside it's a joint that's made up of many components, according to the American Academy of Orthopaedic Surgeons. Because your knee is so complex, it's highly susceptible to various injuries. And if something goes wrong with one tiny part of your knee, the whole mechanism is at risk of giving out when it attempts to go through routine activities such as bending and extending.
A sprain is a stretch or tear of a ligament. Common sprains in your knee involve damage in your medial collateral ligament or anterior cruciate ligament. If you have sprained a ligament, you may have heard a popping or snapping sound when you injured it. You may also notice that you can’t put any weight on the affected leg, you have pain when you try to bend your knee, you have swelling in your knee and your knee gives way or buckles when you’re walking or otherwise putting any weight on it, according to the UCSF Medical Center.
- A sprain is a stretch or tear of a ligament.
- You may also notice that you can’t put any weight on the affected leg, you have pain when you try to bend your knee, you have swelling in your knee and your knee gives way or buckles when you’re walking or otherwise putting any weight on it, according to the UCSF Medical Center.
Elbow Pain From Working Out
It's also possible to feel as though your knee might give out -- giving you a sense that your knee is unstable with activities such as bending -- without actually having instability in your knee caused by torn or stretched ligaments. Patellofemoral dysfunction, which is also sometimes called runner’s knee, can also lead you to feel as though your knee will buckle when you bend it. Runner’s knee occurs when your kneecap doesn’t track properly over a groove in your thighbone when you bend and straighten your leg, according to the website Kids Health, part of The Nemours Foundation's Center for Children's Health Media. This can also cause pain because it irritates the groove and may wear away cartilage beneath your kneecap. Some of the most common symptoms of runners knee are pain and tenderness behind or on the sides of your kneecap, swelling in your knee, worsened pain when you bend your knee and pain when you sit with a bent knee for an extended period of time.
- It's also possible to feel as though your knee might give out -- giving you a sense that your knee is unstable with activities such as bending -- without actually having instability in your knee caused by torn or stretched ligaments.
Your doctor may use a series of assessment tools when she’s trying to determine what’s causing your knee to buckle when you bend it. She will take a medical history, asking questions about how long you have had symptoms and whether you know of a time when you injured your knee. She may also press on your knee and take it through actions such as bending, rotating and straightening it to feel for any injury. Depending on the severity of your condition, she may also ask you to walk around, bend and straighten your knee on your own, according to the American Academy of Orthopaedic Surgeons. Your doctor may also order X-rays and an MRI to assess your knee from the inside.
- Your doctor may use a series of assessment tools when she’s trying to determine what’s causing your knee to buckle when you bend it.
How to Tell if You Have a Bruised MCL
The treatment for your knee will depend on the underlying cause. If you have runner’s knee, your doctor may assign home care treatment strategies such as resting and icing your knee, taking anti-inflammatory medications and doing strengthening exercises once the swelling diminishes. If you have a ligament sprain, the treatment also depends on the severity of the sprain. If your sprain is mild to moderate, your doctor may prescribe physical therapy and pain reduction methods such as those used for runner’s knee. A complete ligament tear usually requires surgical reconstruction or repair, according to the Sports Medicine Institute at the University of Minnesota Orthopaedics.
- The treatment for your knee will depend on the underlying cause.
- If you have runner’s knee, your doctor may assign home care treatment strategies such as resting and icing your knee, taking anti-inflammatory medications and doing strengthening exercises once the swelling diminishes.
Elbow Pain From Working Out
How to Tell if You Have a Bruised MCL
Pain Above the Knee Cap With Running
Pain in Back of Knee in Hyperextension
Meniscus Knee Pain and Running
Knee Pain From Kicking a Ball
Elbow Is Snapping During Exercise
Ew, Why Are My Joints Cracking and Popping?
What Causes Outer Knee Pain While Running?
Tennis Elbow or a Torn Ligament?
- Sports Medicine Institute – University of Minnesota Orthopaedics: Knee Instability
- National Institute of Arthritis and Musculoskeletal and Skin Diseases: Knee Problems
- TeensHealth from Nemours: Knee Injuries
- KidsHealth from Nemours: MCL Injuries
- UCSF Medical Center: A Female’s Aching Knees
- American Academy of Orthopaedic Surgeons: Unstable Kneecap
- American Academy of Orthopaedic Surgeons: Common Knee Injuries
- TeensHealth from Nemours: Runner’s Knee
- Lespasio MJ, Piuzzi NS, Husni ME, Muschler GF, Guarino A, Mont MA. Knee Osteoarthritis: A Primer. Perm J. 2017;21:16-183. doi:10.7812/TPP/16-183
- Kiapour AM, Murray MM. Basic science of anterior cruciate ligament injury and repair. Bone Joint Res. 2014;3(2):20-31. doi:10.1302/2046-3758.32.2000241
- Doral MN, Bilge O, Huri G, Turhan E, Verdonk R. Modern treatment of meniscal tears. EFORT Open Rev. 2018;3(5):260-268. doi:10.1302/2058-5241.3.170067
- Reinking MF. CURRENT CONCEPTS IN THE TREATMENT OF PATELLAR TENDINOPATHY. Int J Sports Phys Ther. 2016;11(6):854-866.
- Petersen W, Rembitzki I, Liebau C. Patellofemoral pain in athletes. Open Access J Sports Med. 2017;8:143-154. doi:10.2147/OAJSM.S133406
- Frush TJ, Noyes FR. Baker's Cyst: Diagnostic and Surgical Considerations. Sports Health. 2015;7(4):359-65. doi:10.1177/1941738113520130
- Huang YC, Yeh WL. Endoscopic treatment of prepatellar bursitis. Int Orthop. 2011;35(3):355-8. doi:10.1007/s00264-010-1033-5
- Beals C, Flanigan D. A Review of Treatments for Iliotibial Band Syndrome in the Athletic Population. J Sports Med (Hindawi Publ Corp). 2013;2013:367169. doi:10.1155/2013/367169
- Tsai CH, Hsu CJ, Hung CH, Hsu HC. Primary traumatic patellar dislocation. J Orthop Surg Res. 2012;7:21. doi:10.1186/1749-799X-7-21
- Ragab G, Elshahaly M, Bardin T. Gout: An old disease in new perspective - A review. J Adv Res. 2017;8(5):495-511. doi:10.1016/j.jare.2017.04.008
- Lee PYF, Nixion A, Chandratreya A, Murray JM. Synovial Plica Syndrome of the Knee: A Commonly Overlooked Cause of Anterior Knee Pain. Surg J (N Y). 2017;3(1):e9-e16. doi:10.1055/s-0037-1598047
- Vaishya R, Azizi AT, Agarwal AK, Vijay V. Apophysitis of the Tibial Tuberosity (Osgood-Schlatter Disease): A Review. Cureus. 2016;8(9):e780. doi:10.7759/cureus.780
- Zanon G, Di vico G, Marullo M. Osteochondritis dissecans of the knee. Joints. 2014;2(1):29-36.
- Hindle P, Davidson E, Biant LC. Septic arthritis of the knee: the use and effect of antibiotics prior to diagnostic aspiration. Ann R Coll Surg Engl. 2012;94(5):351-5. doi:10.1308/003588412X13171221591015
- Gwinner C, Märdian S, Schwabe P, Schaser KD, Krapohl BD, Jung TM. Current concepts review: Fractures of the patella. GMS Interdiscip Plast Reconstr Surg DGPW. 2016;5:Doc01. doi:10.3205/iprs000080
- Voskuil R, Evenski AJ, Montgomery C, Emory CL. Malignant Bone Tumors of the Knee: How to Identify and Treat. J Knee Surg. 2019;32(4):305-314. doi:10.1055/s-0038-1675828
- Gupte C, St mart JP. The acute swollen knee: diagnosis and management. J R Soc Med. 2013;106(7):259-68. doi:10.1177/0141076813482831
- American Academy of Orthopedic Surgeons. Unstable Kneecap.
- Bhatia D, Bejarano T, Novo M. Current interventions in the management of knee osteoarthritis. Journal of Pharmacy & Bioallied Sciences 2013 Jan-Mar;5(1):30-38. doi:%2010.4103/0975-7406.106561
- Bronstein RD, Schaffer JC. Physical Examination of the Knee: Meniscus, Cartilage, and Patellofemoral Conditions. J Am Acad Orthop Surg. 2017 May;25(5):365-374.
- Browne K, Kurtz CA. How to perform a comprehensive examination of the knee. JAAPA. 2009 Jun;22(6):20-25.
- Hergenroeder AC, Harvey BS. (2017). Osteochondritis dissecans (OCD): Clinical manifestations and diagnosis. Bachur RG, ed. UpToDate. Waltham, MA: UpToDate Inc.
Christa Miller is a writing professional with expertise in massage therapy and health. Miller attended San Francisco State University to earn a Bachelor of Arts in creative writing with a minor in journalism and went on to earn an Arizona massage therapy license.