Knee Bucking & Weakness When Walking

Knee Weakness Climbing Stairs or Walking

The knee is an incredibly complex joint that goes through a tremendous range of motion. It has many muscles that cross the knee joint to help control its movement while walking, running, squatting, or going up and down stairs. All of this movement occurs while supporting our body weight. The internal components of the knee include several strong ligament structures that prevent excessive shearing motions. Likewise, we have several strong muscles that cross the outside of the knee joint including the quadriceps, hamstrings, and gastrocnemius muscles.

The internal ligaments and structural supports of the knee are the last line of defense against the damaging shearing movements. The knee should be controlled and supported by the many muscles that cross the knee joint. If any of the muscles begin to weaken, it will eventually increase stress and strain to the adjacent tissues.

Most times knee pain does not occur with a single traumatic event. Rather, it is usually the result of chronic repetitive motions and movements that cause micro tearing and damage to the soft tissues, eventually leading to larger injuries. Small tears become larger tears.

Knee Motions and Movements

knee model posterior labeled

Normally the knee goes through a hinge motion with a slight amount of rotation. When the muscles cannot properly stabilize and support the knee during these movements, the knee feels weak or wobbly. Weakness is more prevalent while going up or down stairs, or descending on a decline. These movements place increased stress on the knee and require greater stabilization from all the muscles.

There are several types of muscle dysfunctions that lead to knee injuries. Muscle strength is how much force we can generate, while endurance is how long those muscles can properly contract. Another dimension of muscle control is stabilization, which requires many muscles to work together to keep the knee in the proper position. With age and inactivity, we commonly lose strength, endurance, and stability.

Treatment improves strength, endurance, and stability to reduce the stress and strain on the knee. Treatment restores normal muscle function and movement patterns. A strong and stable knee does not buckle or wobble when walking on an unstable surface or going up and down stairs.

Knee joint movement dysfunction is increased whenever any of the soft tissues become excessively overwhelmed and injured. Several types of knee injuries that affect knee stability include patellar tendonitis, chondromalacia patella, iliotibial band syndrome, MCL sprains, LCL sprains, and meniscal thinning. Likewise, damage to the small supportive tissues and tendons around the knee can also result in mild chronic knee pain and joint dysfunction.

Anatomy of the Knee Joint

knee model lateral view labeled

The large femur sits atop the tibia, much like two pillars stacked on top of each other. The smaller fibula bone is on the outside of the tibia in the lower leg. The fibula provides some weight bearing, but not nearly as much as the tibia does. At the end of the femur are two large condyles with rounded edges that allow for the rocking or hinging motion associated with knee movement.

In between the femur and the tibia are fibrocartilage shock absorbers, or meniscus. Several large stabilizing ligaments on the inside and outside of the knee prevent excessive forward and backwards movements. These stabilizing ligaments include the Anterior Cruciate Ligament (ACL) and Posterior Cruciate Ligament (PCL).

The patella bone sits in front of the femur and slides in a groove. The backside of the patella is covered with hyaline cartilage along with the front side of the groove on the femur, which minimizes the friction as the patella slides. The patella is a large sesamoid bone, which means it is surrounded in muscle or tendon. Sesamoid bones act as a pulley system to change the direction of forces, in this case from the quadriceps muscle to the tibia.

The knee is a complex joint that is surrounded by a ligament joint capsule and lined with a synovial membrane that produces synovial fluid, which helps lubricate the knee. The lubrication reduces friction and damage to the internal components of the knee. Bursa are fluid-filled sacs that help reduce friction as muscles and tendons glide across the bursa.

Home Treatments

At home the first step is always PRICE: protect, rest, ice, compress, and elevate. Reduce the stress and strain to the knee. Over the counter nonsteroidal anti inflammatory drugs (NSAIDs) as recommended by your doctor can help reduce pain and inflammation. Ice helps block the knee pain and reduce inflammation.

Medical Treatments

NSAIDs are often prescribed for the initial acute injury stages. In severe cases that involve multiple joint regions, muscle relaxers or oral steroids can be given. Trigger point injections, botox, or steroid injections can be treatment options, as well. Pain management is not usually required unless stronger medications or joint injections are involved in treatment.

MRI and X-rays will not usually be ordered to evaluate mild to moderate muscle, tendon, and ligament injuries. Severe cases may utilize advanced imaging to rule out bone fractures, edema, nerve entrapments, tendon or muscle ruptures. Nerve conduction velocity (NCV) testing may be utilized in cases that also involve muscle, sensory or reflex loss.

Conservative Treatments

Therapeutic treatments for addressing soft tissue injuries involve massage therapy, manual therapy, trigger point therapy, Graston Technique, or Active Release Technique. These treatments increase blood flow, decrease muscle spasms, enhance flexibility, speed healing, and promote proper tissue repair.

GT therapy

Iliotibial band Syndrome is common in runners who develop the injury because of weakness and poor stabilization of the leg and hip muscles. Specific knee exercises are given to increase strength and endurance. Proprioception exercises help teach the muscles how to work together again to stabilize the knee during walking or running.

When these treatments are incorporated into a treatment plan, patients heal faster and are less likely to have long-term pain, soft tissue fibrosis, or scar tissue in the injured muscle. These soft tissue treatments are incorporated with therapeutic exercise and flexibility programs.

Video: Scar Tissue Treatment with Graston Technique for Muscle Pain

Cold laser is another effective treatment at decreasing pain and inflammation, while improving function. Class IV cold lasers emit specific wavelengths of energy that enhance the body's healing mechanisms while decreasing inflammation around the knee. It also helps decrease activity from pain sensors that are sending excessive pain signals to the brain. Cold lasers are commonly used to treat knee injuries and damage to leg muscles.

Improve Movements to Eliminate Knee Pain

The lower extremity works as a comprehensive unit performing many of the repetitive tasks at home, work, and during recreational sports. Injuries to one area of the musculature often indicate that additional damage has been incurred by other muscles.

vibration squat exercise

Many therapeutic exercises can help restore proper strength and endurance to the leg muscles. Isometric exercises are often the initial treatment exercises, followed by single plane rubber band exercises for the hip, knee, and ankle: flexion, extension, adduction, abduction, circumduction, inversion, and eversion. Dynamic exercises involving stability foam, rubber discs, exercise ball, and BOSU balls can be performed on the floor. The more unstable of the surface, the more effort and stabilization is required of all the lower extremity muscles.

Vibration plates enhance neuromuscular learning throughout the ankle, knee, foot, hip, and back muscles. Additional strength exercises can be found on the hip, knee, and foot strengthening pages. More information for injuries and treatments for knee pain and foot pain.

Our Chandler Chiropractic & Physical Therapy clinic treats patients with a variety of muscle, tendon, joint, and ligament injuries. The clinic provides treatment for runners, tri-athletes, and weekend warriors in addition to common headache, neck, and back patients traditionally seen in Chiropractic, Physical Therapy, Massage Therapy clinics. We work with all ages and abilities of the residents in Phoenix, Tempe, Gilbert, Mesa, and Chandler AZ.