A knee that goes beyond its normal limits will typically illicit pain, and could possibly set up the joint for a future of subsequently related injuries. A client with a current knee hyperextension or a history of such a problem requires that his or her attending massage therapist be aware of several anatomical and physiological facts. When addressing a hyperextended knee, bodyworkers are most useful to their clients when they know what type of activities could exacerbate the knee’s instability and which muscles benefit most from circulatory massage.
Most people are aware of how easily the knee can be injured from twisting. However, fewer realize that straightening the knee beyond a straight line is another type of misalignment that can pave the way for more serious knee injuries. Over time, knee hyperextension can:
- Strain or tear ligaments
- Degenerate local cartilage (including the meniscus)
- Cause arthritis of the knee joint or kneecap
- Fracture the tibia
In many of the body’s joints, ligaments and tendons play a major role in preventing excessive motion. If those tissues become too loose, the joint can move in ways that cause damage or set the stage for injury. Known as a hypermobile joint, the knee is particularly vulnerable to this problem. Experts agree that keeping the knee stable requires balancing the knee-extending strength of the quadriceps with the knee-flexing strength of the hamstrings and other knee-flexing muscles.
Normally, the ligaments and tendons surrounding the knee pull taut and stop the femur and tibia at the point where they lie directly in line with each other. The tissues at risk of being overstretched causing knee hyperextension include:
- The cruciate ligaments deep inside the knee
- The medial and lateral collateral ligaments on the inner and outer surfaces of the knee
- The popliteal ligaments, which cross the back of the knee
- The hamstring tendons coming down from the back of the thigh
- The gastrocnemius tendons coming up from the calf
According to Tressa Gorman Crehan, associate director of the University at Buffalo dance department and a professor of anatomy and kinesiology for dancers, hyperextension “can cause trauma to the knee capsule and, eventually, depending on the severity, can cause tearing or strain on the ligaments in the back of the knee.” The anterior cruciate ligament, which helps prevent the tibia from moving too far forward in relation to the femur, is particularly susceptible to injury.
Repeated hyperextension of the knee places high levels of stress on the lower leg as well, and can lead to shin splints. In more extreme cases, it can result in tibial fractures. Knee hyperextension can also tilt the top of the pelvis forward, which can stress the hip joints, overarch the lower back and disturb posture all the way up to the head.
Causes and Exacerbation
Hyperextended knees can develop at an early age, lending credence to the belief that some are genetically more prone than others. However, this over-straightening of the knee is a common result of posture and movement anomalies from certain types of activities, such as from volleyball, dance, gymnastics, soccer or yoga.
Because a tight soleus can pull the tibia back, activities that tighten this muscle may encourage knee hyperextension. Women who wear high heels are particularly prone to this misalignment because of the tension the foot’s angle places on the soleus. Massage therapists working with knee hyperextension can work to enhance circulation and lengthen the soleus to reduce this vulnerability.
Several ballet forms and yoga poses encourage participants to “lock” their knees, a position that strains the knee joint’s extension capacity. A “locked” knee relies on shortened quadriceps muscles. Thus, bodyworkers can provide relief by kneading this large muscle group to achieve quadriceps relaxation.
Bodyworkers can help those with knee hyperextension problems by advising clients to avoid exacerbating activities and by working on the tightened muscles encouraging the misalignment. Strengthening the thigh musculature, minimizing stress on the soleus, massaging the soleus, quadriceps and other local tightened muscles as well as avoiding locking the knees, can all help prevent future pathologies arising from chronic hyperextension of the knee.
Cole, Roger, Please Your Knees, Yoga Journal, February 2009; 101-04.
http://www.dance-teacher.com/sections/health/122, Hyperextension and Bowleggedness, Michelle Velucci, Retrieved February 15, 2009, DanceTeacher, MacFadden Performing Arts Media, 2009.
http://www.yogajournal.com/practice/997, The Hyperextended Knee, Julie Gudmestad, Retrieved February 15, 2009, Yoga Journal, 2009.