The Following Studies and Articles Proves the Many Benefits of Squatting on a Knee Saver
Over the years I have heard about the lack of research about the Knee Saver. I hope this page finally puts that myth to rest. You will rarely see so many studies and articles about a product anywhere. Remember, NONE of this was sponsored by the companies making it. Another rarity.
The Physics of Squatting and Using the Knee Saver
First, let’s take a look at the physics why the Knee Saver may help. You can download the study here but this is the conclusion by a physics professor:
The beating inflicted upon the meniscus and other pieces of soft tissue in the knee is substantial. Hence the invention of “Knee Savers”–you know, those triangular pads attached to the back of the lower legs that prudent catchers wear.
Since we now understand how the forces work in a see-saw, we can add the upward force on the upper body from the Knee Saver as shown above. There are many ways to think about how this additional force reduces the upward force the tibia exerts on the femur, reducing the pressure on the meniscus.
You can think about the force from the Knee Saver canceling part of the weight of the upper body, thereby reducing the size of the downward force and, as a result, theupward force.
Since we now understand how the forces work in a see-saw, we can add the upward force on the upper body from the Knee Saver as shown above. There are many ways to think about how this additional force reduces the upward force the tibia exerts on the femur, reducing the pressure on the meniscus.
You can think about the force from the Knee Saver canceling part of the weight of the upper body, thereby reducing the size of the downward force and, as a result, the
Another way to think about the Knee Saver force is that it supplies additional counter-clockwise rotation on the see-saw, reducing the need for the counter- clockwise rotation from the downward force, thus reducing the downward force and thereby reducing the upward force, as well.
Finally, you could just look at the Knee Saver force as providing some of the upward force so the upward force at the knee can now be smaller. No matter how you look at it, the Knee Saver is appropriately named, as it reduces pressure on the meniscus.
Studies and Articles About the Knee Saver and Squatting in Other Occupations
On Catchers
Study One:
Effects of Knee Savers on the quadriceps muscle activation across deep knee bending postures.
Effects of Knee Savers on the quadriceps muscle activation across deep knee bending postures. Workers who kneel or squat frequently are at a high risk of developing knee pathologies. Knee Savers® are wedge-shaped pads, worn on the lower calf by baseball catchers that aim to reduce this risk. This study examined how Knee Savers® change the bilateral quadriceps muscle activity during dorsiflexed kneeling, and heels-up and flat-foot squatting. For twenty participants, integrated and peak electromyography (EMG) during descent and ascent phases, mean EMG during a 10-s static phase, and participants’ subjective perception of muscle fatigue were compared between equipment conditions (with (W) and without (WO) Knee Savers®). Knee Savers® did not significantly reduce integrated or peak EMG during transitions into and out of the postures; however, they significantly reduced (p < .03) mean EMG in five of six muscles during the static phase. These findings indicate potential for Knee Savers® to reduce cumulative muscular effort and fatigue in applications where prolonged static kneeling or squatting are required.
https://www.ncbi.nlm.nih.gov/pubmed/31280805
Article One:
Play ball: Back on the field after catcher’s knee
“He and his colleagues have published a study that describes the condition and are working to build awareness of catcher’s knee and develop injury-prevention strategies. Possibilities include:
a. Catch count: Young catchers would be limited on the number of innings or catches, which could reduce pressure on the knee.
b. Knee savers: A web-shaped pad would rest behind the player’s calf to reduce pressure on the knee.
c. Injury-prevention conditioning to maintain flexibility and balance the quadriceps and hamstring muscles may help young catchers.
https://thriving.childrenshospital.org/catchers-knee-osteochondritis-dissecans/
Study Two:
Catcher’s Knee: Posterior Femoral Condyle Juvenile Osteochondritis Dissecans in Children and Adolescents.
- Catchers developed OCD at a younger age and in a more posterior location on the medial and lateral femoral condyles than noncatchers. These results may represent the effects of repetitive and persistent loading of the knees in the hyperflexed position required of catchers. Increased awareness of this risk may lead to surveillance and prevention programs
- https://www.ncbi.nlm.nih.gov/pubmed/27442212
Article Two:
Catching May Be Fun… But Is It Worth It?
The movements catchers use cause the break down and degeneration of the cartilage of the knee, according to Wesley Pennington, with Bio Mechanics Research Department, Steadman-Philippon Research Institute, in Vail, CO. The torque associated with the painful conditions and stresses that catchers go through, such as repetitive incidents or lower magnitude forces, ultimately make catchers more susceptible to knee injuries than any other position on the field. According to Pennington, the excessive squatting required in the position leaves long time catchers prone to permanent damages of the muscles within the knee. One of the most popular ways to help prevent the injuries is using knee-savers, which are little blocks attached to the back of the shin guards. These are used to increase the angle between the knee and thigh. However, no scientific studies have been conducted to prove how efficient they actually are, says Pennington.
http://www.scijourner.org/2012/11/22/catching-may-be-fun-but-is-it-worth-it/
Study Three:
INVESTIGATION OF BASEBALL CATCHERS’ KNEE SAVERS BY USING MOVEMENT TIME AND MUSCLE ACTIVITY
Through the study, it is revealed that the catcher who wears the knee savers can improve his performance and change innervation pattern of lower extremity muscles.
http://cjsb.org/paper/2007TSBS/2007TSBS/2007%20(9).pdf
Article Three:
How to Protect the Knees of a Catcher
Knee-Savers: This is an interesting invention that is about as simple as it gets. A knee-saver is a little cushioned block that sits atop the back of the shin guards. This physically prevents the catcher from squatting fully down on their knees. The purpose is to increase the angle between the thigh and the knee which results in less stress being placed on the tendons, muscles and cartilage.
Currently, there are no long term studies that have been performed to know if knee-savers really work. However, simply increasing the angle of the knee from the thigh does offer some relief.
http://womens-fastpitch-softball.com/blog/how-to-protect-catchers-knees-from-injury/
Study Four:
Biomechanical Analysis of the Deep Squatting Position in Baseball Catchers With and Without Knee Saver™ Pads
Knee SaverTM pads did not significantly reduce the knee flexion angles in the two most commonly performed squats for a catcher. Based on our load cell model, Knee SaverTM pads received a combined 45.1% of a catcher’s body weight during a normal receiving squat. Therefore, any ergonomic value is likely attributable to force redistribution as opposed to alteration of squatting mechanics. It is possible that Knee SaverTM pads may help reduce overuse injuries to the knee by reducing the force across the knee joint without altering squatting mechanics. Further studies are needed to better elucidate possible benefits of Knee SaverTM pads in overuse injury prevention.
(My thoughts: This is why Knee Savers need to be thick enough to alter the angle of knee flexion. This is why my product was four-sided)
https://med.virginia.edu/orthopaedic-surgery/wp-content/uploads/sites/242/2018/06/CARR-2018-RRD.pdf
Study Five:
LOWER EXTREMITY KINEMATICS OF ACL-REPAIRED AND NON-INJURED FEMALES WHEN USING KNEE SAVERS®.
When squatting with and without KS, the non-injured group experienced more frontal plane motion at the knee, compared to the ACL-repaired group. However, while KS are purported to influence lower extremity joint positions during the bottom phase of a deep squat, the data from the current study did not support this claim. Additionally, KS appear to slow ascending velocity for those without a history of ACL-repair. These findings may have clinically meaningful implications for athletes who use KS during sport activities.
https://www.ncbi.nlm.nih.gov/pubmed/29181251
Study Six:
Effects of Using Knee Savers on Lower Extremity Kinematics in Male Collegiate Baseball Catchers During Squatting
Based on our findings, the purported benefits of knee savers have yet to find scientific validation and may represent only the placebo effect.
(My thoughts: They did no force measurements in this study).
http://www.texasorthojournal.org/vol1_issue1/07GRAYetal.aspx
Study Seven:
This was my study done on catchers to see their knee injury rate. It was never published as I got too busy being a doctor
Evidence from epidemiological studies suggests that certain occupational activities are associated with degeneration of the knee. Baseball lore is abundant with tales of catchers with “bad knees,” and yet, to date, there have been no studies published on the occupational activity of baseball catching as it relates to knee injuries, either acute or chronic. The objective of this study was to determine to what degree professional baseball catchers have an increased risk of chronic knee pain or meniscal damage, compared to baseball players at other positions. Surveys were sent to each athletic trainer for every Major League Baseball team asking their catchers about chronic pain and history of knee cartilage surgery. Catchers were found to be nearly 4 times as likely to have had meniscal surgery, compared to right fielders. Though the incidence of meniscal surgery between catchers (39%) and first basemen (29%) was higher, the difference was not statistically significant. There were no significant differences in knee pain between the three groups of players. Our study lends support to a possible “Catcher’s Knee” syndrome or a disorder of the knee occurring in baseball catchers that includes an increased risk of meniscal damage, possibly related to the years of playing in the squatting position. This syndrome may lead to chronic pain and osteoarthitis in the future.
On Other Occupations
Study One:
Men with frequent occupational squatting/kneeling and heavy lifting have a greater likelihood for worse cartilage morphology scores at the patellofemoral joint. These findings add support to the important role of biomechanical loading on the pathogenesis of knee OA, particularly patellofemoral OA.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2758236/
Study Two:
Knee OA is an increasingly common cause of morbidity and work limitation in later life. Occupational activities that physically load the joint – notably, squatting and kneeling for substantial parts of the working day, regular heavy lifting, climbing, and high physical workload – are likely to contribute to disease occurrence and/or progression and to symptom aggravation. Where possible these exposures should be minimised at source by job design, difficult though this may be to achieve in practice. In any event, workers who are overweight and who have these elements in their daily work should be strongly encouraged to lose weight.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3428837/
Study Three:
There is moderate quality evidence that longer cumulative exposure to kneeling or squatting at work leads to a higher risk of osteoarthritis of the knee. For other exposure, there was no exposure dose-response or there were insufficient data to establish this. More reliable exposure measurements would increase the quality of the evidence.
https://www.sciencedirect.com/science/article/pii/S2093791116301391
Study Four:
In another study published in Arthritis and Rheumatism in July of 2000, employees in England who spent more than 1 hour of their workday for longer than a year, involved in activities consisting of prolonged squatting or kneeling, had nearly double the risk of developing arthritis compared to similar people who did little squatting or kneeling.
https://www.ncbi.nlm.nih.gov/pubmed/10902744
Study Five:
THE APPLE SEED
“By virtue of the looseness of the meniscus, particularly in its posterior portion, it is quite vulnerable to chronic damage so that it is more likely to be hurt by chronic overflexion of the knee. Frequently the damage comes on insidiously as a result of squatting with the heel against the buttock for long intervals on frequent occasions. As the knee moves into complete flexion, the back of the meniscus may be caught between the impinging femoral condyle and tibial plateau and thrust forward, much as one would pinch an apple seed between his finger tips. This strains the posterior peripheral attachment until the meniscus may actually snap in front of the femoral condyle and finally progress to the typical bucket handle position and lie within the notch in front of and medial to the lateral articular condyle of the femur.”
Donoghue; Treatment of Injuries to Athletes; Philadelphia: W.B. Saunders, 1976. p. 632
Study Six:
THE WRENCH
“The main danger occurs (while squatting) when the center of rotation for knee flexion is altered because of the pressing together of the tissues of the calf and thigh. As one descends, the center of rotation is somewhere within the knee joint, but when the tissues touch, the center of rotation is moves back to the contact area. This creates a dislocating effect at the knee. If the center of gravity of the body is kept forward of this center of rotation by altering the lifting position or if the muscles of the thigh are strong enough to prevent the body from resting on the calves or bouncing on the calves, then danger to the knee may be prevented. The danger is enhanced, however, when…the position brings the line of gravity of the body behind the center of rotation. With the gravity line being located behind the center of rotation, a first-class lever situation with a wrenching, or separating, effect at the knee is produced.”
Kreighbaum and Barthels; Biomechanics: A Qualitative Approach For Studying Human Movement; New York: MacMillan Publishing Company, 1985. p. 232.
Study Seven:
THE CRUSH:
Marked flexion of the knees which in a kneeling or squatting position is combined with external rotation of the tibiae causes marked dorsal displacement of the medial meniscus. This places the anterior portion of the cartilage under abnormal tension while the posterior horn is pulled between the condyles and crushed. If these activities are carried out over a period of months and years they can lead to pressure necrosis of the menisci.
Ricklin et. al.; Meniscus Lesions: Diagnosis, Differential Diagnosis and Therapy; New York: Thieme Stratton Inc., 1983. p. 10.
Study Eight:
THE GRIND
Years of friction from the femur and tibia stress the meniscus. Athletes who must move around in a crouched position grind the thick posterior horn of the meniscus. The horn has trouble securing nutrients and mucoid degeneration occurs in its depths. The degenerated meniscus may then split and the upper or lower piece tear loose to form a flap. Flap tears are like loose bodies tethered at the joint line. They cause predominantly mechanical problems. When this flap catches in the joint, it produces clicking, popping, giving way, slipping and sliding,
Kulund; The Injured Athlete; J.B. Lippinscott Company, 1988. p. 473
MORE REFERENCES
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- Sharrard WJW. Pressure effects on the knee in kneeling miners. Ann R Coll Surg Engl 1965:309-24.
- Sharrard WJW, Liddell FDK. Injuries to the semilunar cartilages of the knee in miners. Br J Ind Med 1962;19:195-202.
- Smillie; Injuries of the Knee Joint; Edinburgh and London: E. & S. Livingstone, Ltd., 1962. p. 119 Reported Knee Pain During Different Tasks Kivimaki , Riihimaki H, Hanninen K. Knee disorders in carpet and floor layers and painters. Scand J Work Environ Health 1992;18:310-6.