Treating Knee Arthritis: A Case for Exercise
More than half of us will get arthritis, specifically OA (osteoarthritis), at some point in our lives, most likely in the latter half of life. But that doesn’t mean you can’t return to similar or modified activity with less pain, because you can!
What is OA (osteoarthritis)?
Symptoms of knee OA include swelling, warmth to the touch, and pain with weight-bearing activities and even at times of rest.OA is a degenerative condition where the cartilage that covers the articulating bone begins to break down, and in the worst case results in bone-on-bone articulation. Specifically with the knee, we’re talking about the articulation between the thigh bone (femur), shin bone (tibia), and knee cap (patella). These three bones move together to allow you to squat, clean, run, jump, kick — you name it. Yes, of course, this includes picking things up and putting them down (with good deadlift form, obviously). With any lower extremity movement the knee joint will be stressed, and that is why over time we see degenerative changes.Clinically, OA will be diagnosed by correlation of history, physical examination, and radiologic findings. Symptoms of knee OA include swelling, warmth to the touch, and pain with weight-bearing activities and even at times of rest. Knee OA may present with a loss of range of motion and is most commonly correlated with muscle weakness.
Two Kinds of Knee OA
The tibiofemoral joint is one of the two knee articulations where OA can occur. Radiographic findings will classify tibiofemoral knee OA into four grades. Without getting into too much detail, the scale basically begins with findings of possible extra small bodies of bone in the joint, progressing to extra large bodies of bone with significant joint space narrowing and deformity of the bone ends.If symptoms of OA do come up, you’ve likely had a flare up — a sign that you’ve gone past your joint’s loading ability.The patellafemoral joint is another spot for OA to occur. Patellafemoral OA, or “chondromalacia patella” in some references, is also classified into four grades, beginning with softening of the patella and progressing to fibrillations through the full cartilage and erosive changes down to the bone. It sounds scary, but do not worry; if you have some level of OA, and you are a CrossFitter, most likely you are at the beginning stages of this process.Not everyone will have symptoms with low-grade OA, so if that is the case, keep mobilizing to strengthen the muscles around the joint, and stay away from overloading the joint. “Overloading” equates to using weights too heavy for you, poor biomechanics, too many reps, and not enough recovery time. But if symptoms of OA do come up, you’ve likely had a flare up — a sign that you’ve gone past your joint’s loading ability.
How Do You Address the Problem?
Although you may want to push through the pain, pain combined with swelling has been shown to shut down muscle function around the joint. So how do you get back to hitting the WODs? First we need to get through the acute stage using the common acronym RICE: Rest, Ice, Compression, and Elevation. Getting through the acute stage does not necessarily mean getting it to feel better; rather, the swelling has gone down and you have close to full active range of motion without pain. The last thing you want to do is start loading the joint when there is still significant pain and swelling! Instinctively, you may want to push through the pain, but pain combined with swelling has been shown to shut down muscle function around the joint. In this case, if your muscle — the main shock absorber of the body — isn’t taking the load from the joint, then what is? The joint surfaces and bone! We do not want this to occur with any injury, especially if you have OA. Once the joint has cooled down, we can begin re-educating and strengthening the muscles around the joint. Specifically for knees, we are talking about the quadriceps. This does not mean to go out there and immediately do a WOD with cleans and box jumps, or even air squats for that matter. Instead, the joint needs to be loaded in a progressive fashion.Here is a general progression that we will use:Open chain strengthening at the injured joint and proximal muscles.
1. Closed chain strengthening with resistance less than body weight
2. Closed chain isometric strengthening at full body weight
3. Closed chain dynamic strengthening at proximal muscles groups
4. Closed chain dynamic strengthening at injured joint
What do I mean by “progression”? Once the knee responds well to the load, then we move to the next phase of the progression; we do not do all the steps of the progression in one session.You can work through many of these muscle strengthening progressions on your own using resistance bands.“Open chain exercises” are when the resistance is a movable object (i.e., bicep curl, shoulder press). These exercises are beneficial from a rehabilitation perspective because we can get isolated recruitment for a specific muscle group, simple movement patterns, and minimal joint compression. A “closed chain exercise” is when the extremity being worked is fixed to an immovable object (pull up, handstand push up, squat). Closed chain exercises are good for multiple muscle groups, weight-bearing exercise, and — as we all know and love — functional movement patterns. Progression Exercises Below are several progressive resistance exercises that correspond to the above sequence and will help load the joint in the proper manner. I took a creative approach and demonstrate the movements using items commonly found at a box.
1) Open Chain StrengtheningKnee extension: Muscle strength plays a large role in decreasing stress on the joints, so we are starting with isolating the quadriceps muscle. Resistance band: Tie the band to a pole, have it go under a box, then sit on the box with your foot through the open end of the band. Don’t start with the knee fully bent: focus on partial range and then build up to full knee flexion if there is minimal pain. Completely extend the leg to maximally contract the quadriceps. Kettle bell: Start with a low weight looped around the foot. Same instructions for contraction as with the resistance band.
2). Hip abduction (AKA Jane Fondas): We are isolating the hip abductors, which has been shown to affect biomechanics of the knee. Don’t let these fool you — your butt will burn!Resistance Band: Lay on your side while holding onto a resistance band and have it loop around both feet. Have the top leg slightly behind the bottom leg, then raise your leg towards the ceiling. The tendency is to begin rotating the hips, so stay sideways and focus on keeping the knees pointing forward.
3). Hip Lateral Rotators: Same idea here as with the hip abductors. Strengthen surrounding muscle groups to assist with kinetic chain alignment.Resistance Band: Lay on your side while holding a resistance band and loop it around both thighs near the knee with both knees bent. Bring the top knee up against the resistance.
4). Closed Chain Strengthening with less than body weight:Normally we’d use a shuttle or leg press to get a lower extremity closed chain exercise done with less than bodyweight. Since we do not have that at box, we can use the rower.Knee extension with resistance band: Wrap a resistance band around the foot plates of the rower and then around you lower waist. Extend to the knees to contract the quadriceps. This can be done with one leg to really isolate the affected extremity (which isn’t shown in the picture below).
5). Closed Chain Isometric body weightNow we begin to load with body weight while holding a static position, which is easier than a dynamic movement. Keep the knees over the toes and be aware of our body’s natural tendency to shift away from the injured side. You should feel the burn in your quads. Start with a higher wall sit and progress to a lower position.
6). Closed Chain dynamic strengthening at proximal muscle groupsThis is basically doing a side step with a resistance band to strengthen the hip abductors. Have a slight knee bend, almost into a quarter squat, then step out keeping the toes forward. If your toes start to move outward you won’t target the muscle groups we want.
7). Closed Chain dynamic strengthening at the injured joint. This would be your air squat. Start with partial depth to see how the knee responds. Progressively get to full range if tolerable and add load later down the road. Things to Keep in Mind for OA Increased duration should be emphasized over increased intensity.There will be some discomfort during or immediately after exercise. This does not mean the joint is being further damaged. If pain persists two hours after and exceeds pain severity before exercise, you should reduce the duration and/or intensity. Once you get through this progression, be smart about your training and scaling to reduce future flare ups. Possible ideas are to decrease the weight and/or increase repetitions. Maybe do more repetitions at half range if going down below parallel is painful. How about a power clean instead of a squat clean? Listen to your body and it will let you know if your junky joint isn’t ready.
ReferencesM Dutton. Dutton’s Orthopaedic Examination, Evaluation, and Intervention. 3rd ed. McGraw-Hill Companies, Inc. 2012CC Goodman, KS Fuller. Pathology, Implication for the Physical Therapist. 3rd ed. St Louis, Missouri. Saunders Elsevier. 2009WR Thompson. ACSM’s Guidelines for Exercise Testing and Prescription. 8th ed. Balitimore, MD. Lippincott Williams &Wilkins. 2010