Not about FRICTION anymore, the myths about iliotibial band syndrome.

Do you still prescribe IT band stretch to athletes with IT band syndrome?

IT band syndrome has long been thought to result from friction between of the tight IT band and lateral epicondyle of femur. It may sound reasonable in the beginning.
In fact, IT band syndrome is an overuse injury related to training load error. Either abrupt increase in running distance or training intensity will increase the injury risk. However, there are some terrible misunderstandings that make athletes spend their time on useless stretches. Let’s take a look at the newly found facts that may oppose to what we used to call “general concepts.”

The IT band is a ligament-like structure well fixed to the lateral thigh. 

• The proximal part of the IT band is a three-layer structure. The superficial and intermediate layers are part of the fascia of Tensor Fascia Lata muscle. The deep layer extended to the hip joint and merged with the joint capsule. 
• The middle part, or the tendon part of the IT band connects to the fascia of vastus lateralis muscle and posterior hamstring muscle. 
• The distal part of the IT band also collects fascia fibers from lateral thigh muscles, attaches to Gerdy’s tubercle at lateral tibia and further continues to form part of the lateral collateral ligament of knee. 

The IT band is so strong and firm that nearly responds to mechanical tension force. 

According to a cadaver research, The total length of the iliotibial band remained almost the same after repetitive stretching.

Instead of friction, soft tissue under the iliotibial band I fact undergoes compression during the movement of the lower extremity. 

The compression is greatest with the eccentric load when the hip is slightly extended and adducted with the knee joint flexed. It happened to be the posture of the trailing leg when we walk downstairs or run downhill. And that is the reason trail runners are more susceptible to IT band syndrome.

Return to Sports from iliotibial band syndrome

Nowadays, we have the athletes to stay active when the acute pain subsided. Rehabilitation programs should be started to prepare for returning to sports.

1. Gait analysis is helpful in detecting risky gait pattern such as cross-over gait, trunk wobble or hip drop. Prolonged ground contact time is another factor to be corrected. Ground contact time in elite athletes may be as short as 170 ms while it can exceed 220 ms in marathon enthusiasts. Velocity-based training may be the key method to shorten the ground contact time. 
2. To achieve maximal exercise load, we make the athletes to run upslope on treadmill. The compression force is less likely to increase during upslope running and thus can keep athletes in better physical activity status. 
3. Core muscle strengthening is important because trunk and pelvis tilting/drop/rotation tend to increase if the core muscles do not play their role as stabilizers effectively and efficiently. Lateral drop of the hip also place the body in the posture more vulnerable to ITBS. 
4. Lateral hip muscles strengthening is another essential program to prevent from recurrence of ITBS. Followings are exercises frequently prescribed to athletes by the author. 

• Clam shell exercise 

• Side raising of leg 

• Monster walk (side walking) 

• Romanian split squat 

• Romanian split deadlift 

• Pistol squat 

Back to our question, will you still prescribe stretching exercise for your athletes suffering from ITBS? If your athletes feel more steady and sure with stretching or massage, the better targets are the muscles contracting the IT band. Therefore, tensor fascia lata, gluteal maximum, vastus lateralis, and lateral hamstring muscles are the muscle to be stretched and massaged.


How do you think about the ideas? Welcome to bring up your opinions.

References：

1. Hyland, Scott, and Matthew Varacallo. "Anatomy, Bony Pelvis and Lower Limb, Iliotibial Band (Tract)." StatPearls [Internet]. StatPearls Publishing, 2019. 
2. Jelsing, Elena J., et al. "Sonographic evaluation of the iliotibial band at the lateral femoral epicondyle: does the iliotibial band move?." Journal of Ultrasound in Medicine 32.7 (2013): 1199-1206. 
3. Devan, Michelle R., et al. "A prospective study of overuse knee injuries among female athletes with muscle imbalances and structural abnormalities." Journal of athletic training 39.3 (2004): 263.
4. Ali, Mohammed, et al. "The use of platelet-rich plasma in the treatment of greater trochanteric pain syndrome: a systematic literature review." Journal of hip preservation surgery 5.3 (2018): 209-219.

The overlooked finger injuries in baseball athletes

Sasaki Roki, this pitcher in Japan samurai, started in the game against South Korea in Baseball U18 World Cup on September 6 but got off the mound soon after merely 19 pitches. Although he still pitched a 153 km/h fastball in the game, his game ended within only 1 inning because of recurrent bloody blister on his middle finger. 

picture resource

Finger injuries have been overlooked for a long time.

According to a statistical review on the sports injuries in Major League Baseball (MLB) athletes from 1998 to 2015, the number of players placed on the disabled list (DL) increased steadily while the average length of each assignment to the DL had remained stable over time. In the same study, although the case number of shoulder injuries declined, the elbow injury continued to rise. While shoulder injuries and elbow injuries accounted for about 20% of all injuries, wrist, hand, and finger injuries together only accounted for about 10% of all injuries.

In our past training program to become a sports medicine specialist, unlike shoulder and elbow injuries, finger injuries somehow were rarely mentioned. In my daily practice, players do not often seek for medical aids for finger injuries unless it was a jammed finger or with obvious deformity/laxity such as a Mallet finger.

If we look back on all finger injuries from 2012 to 2018 in Pro Sports Transactions, there were 131 finger injury events related to an assignment to the DL or the injury list (IL) in MLB. After excluding events related to fractures, infections, and dislocations, 72 events recorded are finger blisters, bruises, strains, or sprains. A worth noting fact is, while 28 injuries had been reported from 2012 to 2016, 21 and 23 cases had been reported in 2017 and 2018, respectively.  The incredible surge of the number of finger injuries in baseball athletes, especially in pitchers is quite a phenomenon. These injuries not only stop the athletes from their routine sports performance but also cause the athletes and the teams great fortune losses. It is still debatable about the cause of this blister spike. People think that altered grip methods and trends toward faster pitch along with changes in the ball texture (the seams hight, the hardness change, the leather, etc.) are to blame.

How stressful are the fingers of the pitchers?

An article by Hiroshi Kinoshita et al in 2017 mentioned that during the acceleration phase, fingers have to bear enormous magnitude of forces through the ball-rolling phase till the ball release.  The maximal resultant force may reach to close to 100 N in the index and middle fingertips. That is like the effort holding a 10 kg object with each fingertip. The resultant force is essential in achieving high ball velocity. In addition to the resultant force, the shear force peak of the index and middle finger may also exceed 100 N. The shear force that generates spin usually are increased by the seam on the ball. The finger-ball friction is also related to finger moisture and the size of the finger pad.

resultant force on the middle finger

The load on the fingers differs when pitching different types of ball. While pitching fastballs, the index and middle fingers contribute almost equally to create backspin on the ball. For pitching curveballs with topspin, the middle finger contribute more than the index finger. As for pitching sliders with sidespin, the index finger's contribution will be greater than the middle finger.

Except for inter-phalangeal differences, the shear force also varies from different types of pitching. The spin rate of curveballs and sliders is usually higher than that of fastballs, thus the shear force should be higher to produce the spin required.

photograph resource

With such enormous forces loaded on the fingers, it is understandable why there are strained flexor tendons and bruises on the fingertips, sometimes even broken nails of the index and middle fingers. The shear force when pitching sliders or curveballs usually causes radial deviation to proximal and distal interphalangeal joints. The accumulated stress may cause injury to ulnar collateral ligaments in the index and middle fingers if the athletes do not rest properly to allow tissue healing. The rectangular force parallel to the ball surface also causes the blisters on the fingertips.

How to prevent finger injuries in baseball pitchers?

Modify your pitch selection and changing grips

Combining different types of pitching in your pitching strategy can prevent excessive friction resulted from sliders or curveballs. Shear force is known to have a linear correlation with pitching velocity. Altering your pitching velocity wisely may not only confuse the batter but also decrease the stress on your fingertips. Changing grips may decrease the spin rate and thus decrease the shear force.

Maintain adequate moisture 

Some pitchers use spray-on antiperspirants to prevent excessive sweating in the palms and fingers.

Cut and shape your fingernails properly

A broken fingernail is usually caused when the ball rolls over the fingertip. The consultant force and shear force may break the nail, even peal the nail out of the nailbed if the nail is not cut and shaped properly. If a nail is broken, a nail cast can be applied for protection.

How to treat blisters?

If a blister is filled with fluid/blood and causes pain, have the fluid drained may provide immediate symptom relief. However, the drainage should be performed only after strict sterilization. Meanwhile, the covering skin should not be removed but maintained as a barrier for the underneath tissue. Close monitoring and cleaning the blister is necessary to prevent infection.

References:

1. Conte, Stan, Christopher L. Camp, and Joshua S. Dines. "Injury trends in Major League Baseball over 18 seasons: 1998-2015." Am J Orthop 45.3 (2016): 116-123.
2. Kinoshita, Hiroshi, et al. "Finger forces in fastball baseball pitching." Human movement science 54 (2017): 172-181.