Exploring Life

[Exploring Life] Knee pain is caused by misalignment of the patella (knee cap), trauma to the knee, or degeneration (arthritis). The most common form of knee pain is patellofemoral pain syndrome (PFS). Patellofemoral pain syndrome , the presence of a dull aching pain behind the knee cap, is due to inflamed cartilage. It is caused by the disproportionate development of muscles around the knee often brought on by chronic misuse. The patella’s cartilage–under the kneecap–wears away; it becomes sandpaper like, often makes a grinding sound because it no longer rides smoothly over the knee joint. The muscles pull the knee cap in an abnormal direction, and the under surface of the knee cap starts to rub against one side of the knee joint causing pain to develop. The condition is most noticeable on stairs – especially walking downstairs, kneeling, placing pressure on the knees by bending them more than ninety degrees, or extending the knees past the toes and exposing them to injury. Correcting the imbalance between the quadriceps and hamstrings is essential to proper knee alignment. Patellofemoral pain syndrome might get better on its own over time, but without proper exercise it may take several years.

There are two forms of patellofemoral pain syndrome : a) patellar compression syndrome; and b) patellofemoral instability syndrome. Patellar compression syndrome involves a tissue-related problem that creates pressure and irritation in the knee between the patella and the knee joint. Patellofemoral instability syndrome involves a tear, slippage, or dislocation that impairs the structural ability of the knee to balance the leg, which may cause either pain, a sense of poor balance, or both. Patellofemoral instability may relate to hip abnormalities or to tightness of surrounding ligaments. In both cases, the knee is painful due to inflammation of the surrounding tissue, and possibly swollen or locked.

The causes of PFS include:

• Hip: Imbalance of adductors and abductors, weakness of external rotators.
• Tight iliotibial band (ITB): The fibrous band that runs the full length of the upper leg from hip to knee may become tight and contribute to patellofemoral pain.
• Quads weakness: Weak quadriceps muscles, especially the oblique part of the vastus medialis head known as the VMO (vastus medialis obliquus), may allow the patella to align to the lateral side. The VMO plays a big role in tightening the medial retinaculum and keeping the patella aligned in the centre of the underlying groove.
• Quads/hamstrings imbalance: It has been found in patients with PFS that the hamstrings are often weak in relation to the quadriceps muscle. A balance in quads and hams contributes to patellar stability.
• Abnormalities of the arch of the foot: Arch abnormalities, especially flat-footedness, can cause an alteration in the alignment of the whole limb with malalignment and maltracking of the kneecap.
• Tight calf muscles: Tight calf muscles can cause a compensatory rolling-in of the foot, with consequent alteration of limb alignment and stress on the kneecap.

Correcting Knee Alignment

The two major muscles groups that control the knee are: a) quadriceps; and b) hamstrings. For the knee to work properly, there must be an appropriate balance of strength and flexibility between the opposing muscle groups of the thigh. A common problem is stronger but less flexible quadriceps than hamstrings – over stretching the hamstrings without comparable stretching of the quadriceps can do more harm than good. The common symptoms of knee misalignment are a grinding feeling as the knee is bent and extended, and snapping of the knee (without pain) when the knee is bending, and pain and inflammation felt directly behind the knee cap.

To correct knee misalignment and associated pain the following rules must be adhered to:

1. Rest: pain and soreness is an indication that rest is absolutely essential – the body must have time to heal itself. The period of time is normally 2-3 weeks;
2. Therapy: Specific exercises that serve to correct knee imbalance and develop correct knee alignment should be done regularly along with rest (see below);
3. Functional Retraining: Any exercise or movement that places direct force through the knees must be avoided. There are a number of contraindications and specific movements/positions that must be avoided: a) sitting for long periods with bent knees; b) kneeling; c) any squatting motion past 90 degrees can cause serious injury; d) any high impact exercises, for example, running and jumping; e) overuse of stairs, especially going downstairs; and f) lunging motions. Any over-flexing of the knee in either direction is always detrimental and a risk for serious permanent injury.

Not understanding the requirements of healthy knee alignment while continuing activities that serve to risk or degrade it can result in permanent injury that may require surgery.
 

Exercises to Correct PFS

A) Sitting (Chair) Exercises for Proper Knee Alignment
Many people are required to sit in a chair for long periods during the day. This can cause a tightening and degradation of movement in the hips and legs. Integrating strength and stretching exercises while sitting can help in part to maintain effective flexibility.
 
The following sitting exercise assume an imbalance between the Quadriceps and hamstrings are the root cause of knee misalignment. It is common practice in physical therapy today to correct the imbalance by placing the emphasis on quadriceps stretching while maintaining a lesser degree of hamstring stretching. Perfect technique is essential to gain benefit. The sitting exercises require good posture with a firm erect spine and sitting the base of the spine firmly on the front edge of the chair so the hamstrings are not confined. The core muscles should be activated and support the body throughout the sitting exercise. These exercises are best continued daily for 4-6 weeks and then used regularly after that to ensure healthy knee alignment.

Note on Leg lifts: Lifting both legs at the same time causes excessive stress on your lower back so only lift one leg at a time; the opposite leg should be kept slightly bent with the foot flat on floor, a form core, and erect posture. Of all the knee exercises, the quadriceps strengthening contraction is probably the easiest, safest and most important exercise you can do to prevent knee pain and injury. Sitting exercise should be done exclusively until knees are healthy enough to move to the standing exercises.
 

1. Quadriceps – Contraction: Keep your leg flat and straight out. Bend your toes towards your head as much as possible and hold this position for ten seconds. Release. Repeat ten times.
2. Quadriceps – Contraction: Keep your leg flat and straight out. Bend your toes towards your head. Raise your leg off the bed six inches and hold it. Keep this position for ten seconds and release. Repeat ten times.
3. Quadriceps – Contraction: Sitting on edge of chair, raise the lower part of your leg so your leg is straight out and hold for ten seconds. Release. Repeat ten times.
4. Quadriceps – Strength: Sit in a chair, place your foot under the bottom edge of a desk or bed with the leg almost straight. Slowly, lift the leg from the top up as though trying to lift the desk or bed off the ground. Your thigh muscles will tighten and become fatigued. Hold for 10 seconds then relax. Repeat 20 times and then do the same with the other leg. Repeat this exercise three times a day for three or more weeks.
5. Hamstring Lengthening Exercises: While sitting in a chair, put your leg straight out in front of you with your heel resting on the ground. Rest both hands on your knee and while keeping your leg straight, slowly slide your hands down the front of the knee towards the foot until you feel a tightening and slight pain in your hamstrings (tendons behind the knee). Hold for 10 seconds, then relax. Repeat 20 times with both legs and perform the exercise three times a day for three weeks. Your hamstrings will loosen and you will be able to move your hands further down your shin towards your foot.
6. Hamstring Strengthening Contractions: Sit in chair, heels on floor. Don’t move heels but pull back on them. You will feel tension in you hamstrings. Hold for count of 10. Relax for count of 3. Do 10 repetitions.

 
B) Standing Exercises for Proper Knee Alignment

1. Quad Strengthening – Standing on One Foot: Hold onto back of chair or counter top for support. Stand on one leg for one minute. Switch sides. As your balance improves, use one hand only for support. Next use one finger only for support, then progress to letting go, but keeping your hands within a couple of inches above chair in case you lose your balance. Do not lean your trunk to one side. To increase difficulty, shift weight onto the ball of the foot.
2. Quad Strengthening – Partial Squats: Double leg partial squat: Stand. Keep Back Upright. Knees pointing straight ahead – inline with feet and hips. Slowly lower yourself. Don’t bend your knees beyond a 90-degree angle, if 90 degrees is too difficult bend even less. Safety Tip: Make sure your knees do not extend beyond your toes when doing partial squats. Keeping your weight behind your knees reduces the pressure on the knee joint during the squat. Bending the knees beyond 90 degrees (a right angle) places excessive strain on the knee.
3. Quad Stretching – Hip Flexor and Knee Extensor Stretch: Stand on one foot, raise one foot behind body and grasp foot with hand, pull gently backward while gently moving hip forward. Do not over-flex the knee – pull foot more backward than upward behind body focusing on hip flexor – knee structure can be strained by over-flexing the knee in an upward direction. Note – exercise can also be done lying down on one side of the body with the same caution applied.
4. Quad Stretching – One-leg Kneeling Extensor Stretch: Moderate lunge position – front knee is directly over the ankle and never moves beyond this or to the left or right – back leg extends backward with lower half of leg resting on floor – gently move hips forward and move torso into upright position if an increased stretch is required.

 
C) Supporting Muscles for Proper Knee Alignment
Other muscles that affect knee stability, to a lesser degree than the quadriceps and hamstrings are the calf muscles, the hip abductors located on the outer thigh, and the hip adductors located on the inner thigh. The body functions as a unit and muscles that are not near the knee can contribute to knee stability. Some of the standing exercises above incorporated stretching of the hip abductor muscles.
 
Sitting Exercises (Chair and Floor) to Support Knee Alignment

1. Hip Adductors (Inner Thigh) / Groin Muscle and Inner Quad Muscle Strengthening: Put fist between knees, squeeze together knees. Hold for count of 10. Relax for count of 3. Do 10 repetitions.
2. Iliotibial Band (Pelvis to Knee) Stretch: Bring right foot to outside of left leg, bringing knee towards opposite shoulder so that the knee crosses the mid-line of the body. Hold for 30 seconds. Repeat on other side.
3. Hip Adductors (Inner Thigh) Stretch: Sit on floor, spread legs into a v position. Slowly lean forward from your hips, keeping your back straight, until you feel the stretch. Do not bounce. Then lean towards the right, foot then left foot. Hold each position for 30 seconds.
4. Hip Abductors (Outer Thigh) Stretch: Sit on the floor, legs extended in front of you. Bend right leg and place right foot on floor on outside the left knee. Twist upper body to right and use left elbow to gently push against outside of right nee until you feel a gentle stretch in the right hips, buttocks, and lower back. Hold for 30 seconds. Repeat on other side.

Standing Exercises (Chair and Floor) to Support Knee Alignment

1. Calf Muscles Stretch: Step back with left, forward with right, lean forward with hips. Do not roll foot out to side. Keep heel flat, foot forward. Bend knees for alternate stretch. Hold 30 – 60 seconds.
2. Hamstring Stretch: Standing position
   Keep one leg on ground; put one foot on chair with leg straight. Bend forward at the hip. Do not attempt to touch your toes as this will stretch your back, and the goal of this exercise is to isolate your hamstring muscles in the leg that is being supported by the chair.
3. Iliotibial Band Stretch: Cross right leg behind left leg moving crossing knee beyond the mid-line of the body. Lean from the hips to the left, the stretch being felt on your right hip, side of the leg and knee. Hold for 30 seconds. Repeat on other side.
4. Gluteal Stretch (back of hips / buttocks): Stand in front of chair, about two feet away from chair. Place left foot on chair, leg bent. Bring your chest towards your knee, keeping back straight. Hold for 30 seconds. Repeat on other side.

Conclusions: Maintaining Healthy Knee Alignment

Knee alignment is guided by the quadriceps and hamstrings, and is further supported by the hips and calves. Effective knee alignment requires that both the quadriceps and hamstrings be equally developed so they can work in tandem to keep the knee aligned. An imbalance either way can cause the knee to become misaligned, meaning that the knee cap (patella) does not track properly. Weak and inflexible hips and or calves can also cause a knee to become misaligned. Improper tracking of the knee cap results in wear and tear on the cartilage and surrounding ligaments and tendons. The body’s guardian, pain, notifies us of improper knee alignment through pain directly behind the knee cap, a grinding feeling when the knee is extended and flexed (due to cartilage irritation), cracking noises when the knee is extended or flexed (without pain). Improper knee aligned can become particularly evident on stairs, especially travelling downstairs on a decline of some type, when pain appears.

The immediate reaction required is a) rest – to ensure the body can heal itself and inflammation, if present, recedes – this means minimizing all activities that aggravate the knee for a while; b) contraindications – to ensure that all positions and movements that are contrary to effective knee aligned are immediately eliminated this includes all positions that place direct stress through the knee, any high impact exercise, never over flexing/extending the knee, never squatting past 90 degrees, never doing lateral motions with knees (i.e. – left to right twisting) while the are in a flexed position, no kneeling, never sitting too long in any position; and c) to begin to slowly integrate an exercise program that is specifically designed to correct and maintain proper knee alignment.

Patellofemoral pain syndrome is a common occurrence in athletes and other people that place significant and/or incorrect stresses and strains on the knees. Any way it is looked at, patellofemoral pain syndromemeans that the knees have been abused and they communicate that abuse to us via pain. The condition does not usually require surgery (statistics show only 10% require surgical intervention) and can be repaired over several months of effective care and therapy. The healing process is very time consuming but must be respected otherwise further and potentially more serious injury may occur. Cartilage can repair itself, but the process is very slow as is the correction of muscular imbalances in the quadriceps and hamstrings. Once corrected, the same principles and practices that lead to proper knee alignment must become a consistent and regular practice in everyday life.

Resources

1. Exploring Life Bookmarks: Patellofemoral Pain Syndrome