We take our knees for granted. Only when our knees are painful, do we realize how important they are in our daily lives and how often we squat and climb stairs! But there is hope.
The most common cause of knee pain is easily treated. Instead of driving and waiting for an appointment, an online physical therapist can coach you on the best exercises for knee pain!
Anatomy:
Bones of the Knee
Our knee is made up of the big upper thigh bone, known as the femur, and the tibia or shin bone in the lower leg. The patella or kneecap is in front of the knee. Between the bones is a hard cushion known as the meniscus. The meniscus acts as a shock absorber. Stability to the knee comes from four ligaments:
Knee Ligaments
- The anterior cruciate (ACL) prevents forward motion of the lower leg.
- The posterior cruciate (PCL) prevents backward movement of the lower leg.
- Medial collateral (MCL)provides inward or medial stability
- Lateral collateral (LCL) provides lateral or outside stability.
Causes of Knee Pain:
- Trauma or Inflammatory
Acute trauma to the knee includes fractures, ligament tears, and large meniscal tears.
Inflammatory also includes arthritic conditions such as rheumatoid, psoriatic, reactive, gout, and pseudogout.
Trauma and inflammatory arthritic conditions initiate a chemical process producing inflammation. Inflammation is critical to the healing process. It allows chemicals to be released to clean up the area, increase blood flow, and heal any damaged tissues and bone. But in arthritic and auto-immune conditions, the inflammatory process goes astray.
Trauma also initiates the inflammatory stage but is short-lived, only lasting a few days to a week. A constant throbbing pain characterizes the inflammatory phase.
Knee Treatment for the inflammatory stage:
R.I.C.E.
(rest, ice, compression, elevation)
During the acute/inflammatory stage of healing, RICE (Rest, Ice, Compression, Elevation) is the treatment protocol. Rest depends on the severity of the injury. Fractures, significant inflammation would require complete rest. But most knee injuries require “active rest” or continuing with light activity within tolerance to prevent muscle wasting and poor healing of tendons.
- Ligamentous laxity
Sports that require quick starts and stops and twisting movements on a planted foot can lead to ligament tears in the knee. The most common tears occur in the ACL and MCL ligaments. BUT if you maintain an arch in your foot (ankle bone high), this improves your mechanics, causing bowing of your leg or a varus stress on your knee. It eliminates valgus stress on the knee, the number one cause of ACL and MCL tears.
Knee Treatment for ligamentous laxity: RICE, Reagin full range of motion, strength, balance, and progression to proprioceptive exercises for return to sport.
- Derangement – A problem within the joint secondary to a meniscal tear
Joints have cartilage protecting the outer layer of bone and an extra buffer between the bones. In the knee, this cushion is known as the meniscus. Repetitive motion strains the joint, especially if the movement is awkward or has poor mechanics. This strain can cause microscopic tears in the cartilage and even cause a tiny piece of your cartilage to break off. This is part of the natural wear and tear process, but excessive activity combined with poor mechanics will advance this breakdown, known as a “derangement.” Even though this broken piece is tiny, it can cause pain and loss of motion if it interferes with the joint’s smooth mobility. Derangements are characterized by intermittent pain, pain during movement, and a loss of motion (can be constant pain if a joint is held in an abnormal position such as a dislocation).
Knee Treatment for Derangements: Reduction of derangment, Regain full range of motion, Progress to the recovery of function.
- Tendinosis: Infrapatellar, Distal Hamstring
Tendons are soft tissue at the end of the muscle that attaches the muscle to a bone. Repetitive forces can cause a microscopic breakdown in the cartilage and/or cause the tendon to become tender and irritated. When the tendons break down, the newly repaired tissue needs to be stretched and strengthened to imitate the original tissue. When the newly repaired tendon does not regain proper strength and flexibility, it is prone to re-injury with a return to activity. Pain secondary to a tendon dysfunction is characterized by tissue tightness and muscular weakness.
Knee Treatment for Tendinosis: Regain full tendon flexibility, Eccentric strengthening to load tendon as it elongates, Proprioceptive exercises to help return to sports activity.
- Referred
A proper assessment always starts with ruling out the spine. 43% of isolated extremity symptoms result from a spinal problem causing the nerve to refer pain to the joint. Ruling out the possibility that your knee pain could be referred from your spine is essential for proper treatment and prevention of reoccurrence. The hip also refers pain to in the medial knee. Some with severe hip pain never have pain in the hip joint itself and instead, complain of significant pain along the inside of their knee. A mechanical assessment will easily determine the actual cause of pain by simply moving the spine to see if it produces knee pain. Then the hip is moved into the end range, looking for any loss of motion and production of knee pain. If these joints have a full pain-free range of motion and do not produce knee pain when moved – referred pain is ruled-out.
If you do not address the actual cause of pain, your treatment is in vain.
Knee Treatment for Referred Pain: No treatment of the knee. Instead, address the spinal problem. Knee strengthening may be part of the protocol if there is myotomal weakness.
- ITB Friction Syndrome
One of the most common overuse injuries in runners, but ITB problems also affect cyclists and hikers. It is from improper training or too many miles. The ITB is a thick band that runs from the outside of your hip to the front of your knee. The ITB can rub abnormally on the knee as it crosses the knee, and burning pain can ensue on the outside of the knee.
It is caused by overloaded tissue that cannot repair itself fast enough to keep pace with the stress placed upon it. The ITB band crossed over the knee to attach just below the lateral shin bone. Underneath just above where the ITB attaches a bursa-like tissue to help reduce friction. This tissue gets pinched. Treatments that cause more pressure to this bursa-like tissue only aggravate it further (deep tissue massage, foam rolling).
Knee Treatment: ITB Friction Syndrom: full knee extension, hip stability, proper running form (GOATA: ankle bone high, knee varus)
The most Common Cause of Knee Pain usually happens for no apparent reason.
Pain in the knee can be caused by repetitive trauma and strain or injury. Occasionally it occurs for no apparent reason. When knee pain occurs, you may experience functional limitations that include difficulty walking, rising from sitting, or ascending and descending stairs. The cause is usually misdiagnosed. Often intermittent pain that limits your ability to squat and descend stairs is a minor derangement (or tiny broken particle in your knee). A derangment is easily treated once it is properly diagnosed.
Location of Knee Pain Symptoms
We used to teach that the location of your knee pain would indicate what structures were at fault. In some ways, that is true, but often not.
The most critical indicator is what activities cause your pain and what activities relieve your pain, but as a general guideline:
- Pain in the Front of the Knee:
- Patellofemoral dysfunction (issue with tracking of your kneecap, subluxation)
- Infrapatellar tendonitis/tendinosis
- Patellar fracture
- Internal derangement
- Pain on the Inside of the Knee:
- Medial meniscus
- Medial collateral ligament.
- Arthritis of the medial tibial plateau
- Pain on the Outside of the Knee:
- Internal derangement of the lateral meniscus
- Lateral collateral ligament
- iliotibial band (ITB) stress.
- Hamstring tendons. Strain to this tendon may be a source of knee pain.
- Pain in the Back of the Knee:
- hamstring tendons
- Baker’s cyst. This is an abnormal swelling of the knee joint that occupies space in the back of the knee and causes pain with excessive bending of the knee.
Our next will discuss treatments: Exercises for Knee Pain (Physical Therapy)
