The knee joint is possibly one of the most complex and interesting joints of the human body. For most of us, they are the structure that gets bumped the most on chairs, coffee tables, or medium to large-sized dogs. Those minor traumas aside, we will discuss injuries of the knee below the surface—i.e. within the joint. Most of us have heard of these injuries: ACL tears, MCL tears, meniscal tears, patellofemoral pain syndrome. We have heard of them because they are among the most common injuries suffered by athletes—both elite and amateur. We will talk a bit about why that is, the causes of these injuries, their rehabilitation and prevention. Ready or not….

Anatomy Overview

            On a macro-anatomy level, the knee can be considered a “sandwich” joint: it hangs out between the hip joint and the ankle joint, and to a certain degree is at their mercy. For example, a person with a history of ankle sprains will likely have residual instability in that ankle. However, the body learns to compensate by transferring the load up the chain to the knee. The same thing happens with the hip. A hip injury or muscle weakness (let’s just say, osteoarthritis of the hip) will cause a compensation that passes the load down the chain to the knee. See what I mean? Sandwiched.

            All of that aside, let’s talk about how the knee attaches. There are actually TWO joints that make up the knee: the tibiofemoral (the thigh bone is connected to the shin bone), and the patellofemoral (the kneecap is connected to the thigh bone). (I hope you all sang that with me). For the sake of this article I will talk more about the tibiofemoral joint, as it is the larger of the two and the most commonly impacted by injury.

When we look at the bottom of the femur (thigh bone) and the top of the tibia (shin bone), we notice that there is a lack of bony congruency. This means that the femur does not just sit on top of the tibia like a perfectly placed puzzle piece; it has a little help. The menisci (there are two) cover the top of the tibia and create little basins for the round parts (condyles) of the femur to sit in and glide on during movement. You can think of it like a dense cushion that is perfectly molded to the shape of the femur. Because we would like our knees to bend in order to accomplish myriad activities, the menisci cannot be fused to the femur the way that they are to the tibia: enter, ligamentous support.

            Ligaments are bands of dense, non-contractile connective tissue that provide stabilization to joints by regulating the amount of excessive movement that occurs. They exist to protect our joints while still allowing the dynamic movement that allows us to accomplish everyday tasks.

            In the knee, there are four primary ligaments that provide this “check” to ensure that the joint moves within its feasible ranges. The anterior and posterior cruciate ligaments (ACL, PCL), and the medial and lateral collateral ligaments (MCL, LCL) work together to provide support in all directions (see Image 1).These are the main structures we will discuss regarding injury.

Common Ligamentous Injuries

            The ACL and PCL are in the center of the joint and make an X-shape. These ligaments become taut when the knee is flexed to prevent unwanted motion from multidirectional forces. Seventy percent of ACL injuries are non-contact in nature. They occur during a plant and twist motion, typically in conjunction with a rapid deceleration. We see this a lot in soccer and football players: they’re running down the field, gaining speed, and suddenly slow down and change direction to avoid an opponent or obtain the ball. Just like that, they end up on the ground writhing in pain.

The ACL tears when the knee experiences excessive combined internal rotation and valgus forces (see Image 2). A valgus force is a force that causes the knee to move inward while the hip and ankle remain outside of it. The knee is most vulnerable to injury in this position when it is in a slightly bent position, such as when one initially loads weight onto their leg.

            PCL injuries are relatively rare based on the anatomy of the ligament and typical movement patterns of the knee. They occur by a force that sends the tibia backward; some may have heard of a “dashboard injury,” when the dashboard of a car slams into one’s shins. Another mechanism is hyperextension of the knee. This is extremely rare, as a tremendous amount of force is required to overcome the muscular and bony defenses against hyperextension and rupture the ligament.

            The MCL and LCL are on either side of the knee joint, attaching from the femur to the tibia. They are responsible for making sure the knee moves forward and backward—not side to side. The MCL and LCL can be injured in conjunction with an ACL or PCL injury, or can be injured on their own via a direct force inward or outward on the knee. The MCL is more commonly injured than the LCL, due to its vulnerability as both a smaller ligament and based on the types of forces humans habitually receive on their knees. Athletes are at high risk of injuring these ligaments during contact events, such as a slide tackle.

The Unhappy Triad

            It is important to talk about the “unhappy triad,” as it is a regularly seen pattern of injuries. The unhappy triad includes an ACL sprain, an MCL sprain, and a meniscal tear. The mechanism of injury is typically similar to that of an ACL injury, a plant and twist, with increased compression and valgus forces. The quality of an individual’s tissue and the force of the injury determine which structures will be compromised and how badly.

A Note Regarding the Meniscus

            As it was mentioned in the unhappy triad, I cannot resist sharing just a tidbit about the menisci. As stated in the anatomy section, the menisci make the tibia congruent with the end shape of the femur. A meniscus tears typically due to an excessive shear force, one that compresses and slides perpendicular to the surface of the tissue. There are three types of meniscal tears: longitudinal, radial, and horizontal (see Image 3). Longitudinal tears are along the striations of the tissue. The right hand column of the image shows potential futures for smaller tears, however, the bucket handle tear shown may occur at the time of the initial incident, depending on the force involved. Radial tears begin in the center of the meniscal “basin” and tear outward. These tears may be difficult to heal based on how close together the edges of the tear are. Horizontal tears have at least one portion that is perpendicular to the tissue striations.

            The primary determinant of whether or not a meniscal tear will heal on its own is its location. Tears in the outer third of the meniscus receive better blood flow and have a higher potential of healing on their own. Larger or more internal tears may require surgery.

Options Post-Injury

            In the unfortunate event that you or someone you know experiences a ligamentous sprain one (or several) knee ligaments, there are a number of options. Obviously, a primary care provider should assess the situation. The grade of the sprain will ultimately determine the next steps. Grade I sprains are an over-stretching of the ligament causing inflammation; often there is only micro-tearing at the site. Grade II sprains tear through part of the ligament, but not all of it. The sprains can be resolved on their own or by surgical approximation depending on severity and other patient factors.

            Grade III sprains are the ones that are top of mind: the full ruptures. In this grade of sprain, the ligament has been torn all the way through. Depending on which ligament it is, there may be options to repair, replace, or seek conservative treatment. Repairs and replacements involve surgical procedures to recover the integrity and function of the ligament. Conservative treatment usually consists of some sort of physical therapy to train the muscles around the joint to compensate for the missing ligamentous structure. It may seem odd to no seek a repair or replacement, however there are many people walking around without ACLs today. The decision of how to proceed is based on a person’s health status, age, and goals/use of the joint.

Prevention

            The easiest way to deal with a ligamentous knee injury is to not have one in the first place. Athletes, recreational or elite, would tremendously benefit from a regular exercise regimen that includes mobility and agility training. Mobility training focuses on how joints move and stabilize together to produce full range movements. Agility training is a combination of power and balance. It trains quickness and reaction time, both for voluntary movement and subconscious stabilization. If you have ever watched a sports practice (or participated in one), there are typically drills involving stopping and starting, cutting, and reacting. These drills are extremely important to train our bodies for how to respond to those unpredictable game-day situations.

A lot has been covered in this article: ACLs, PCLs, MCLs, menisci. The bottom line is this: knee ligamentous injuries typically occur from stereotypical movement patterns with extreme forces. There are so many structures in the knee promoting its stability; while ligaments are an integral part, structures like the menisci and the surrounding soft tissue ensure that knees stay in line (literally and figuratively). Ligaments do get stronger with training; as do the neural connections between our brains and every element of our joints. Strong neural connections mean that the messages to turn on and off muscles and react to new stimuli run quickly and efficiently, helping your body function optimally. Work hard, work smart, and remember: you’re the bee’s knees!

Sources:

1. https://www.physio-pedia.com/Knee
2. Knee Ligament Sprain Guidelines: Revision 2017: Using the Evidence to Guide Physical Therapist Practice.J Orthop Sports Phys Ther.2017 Nov;47(11):822-823. doi: 10.2519/jospt.2017.0510.
3. https://www.physio-pedia.com/Anterior_Cruciate_Ligament_(ACL)_Injury
4. https://www.physio-pedia.com/Medial_Collateral_Ligament_Injury_of_the_Knee
5. https://www.physio-pedia.com/Lateral_Collateral_Ligament_Injury_of_the_Knee
6. https://www.physio-pedia.com/Posterior_Cruciate_Ligament_Injury

IMAGES:

7. https://ih1.redbubble.net/image.332330583.4464/flat,750x,075,f-pad,750×1000,f8f8f8.jpg
8. https://www.researchgate.net/profile/Ata_Kiapour/publication/260108175/figure/fig1/AS:392654375407619@1470627506941/Schematic-showing-the-multi-planar-loading-mechanism-of-non-contact-injury-to-the.png
9. https://www.limbreconstructions.com/uploads/5/4/6/1/54615109/2536836_orig.png

Whether you are an athlete, a fitness junkie, or the occasional gym-goer, you have probably heard the phrase, “no pain, no gain.” You may have also been given encouragement in the form of “just keep pushing through.” While these phrases can help us overcome mental obstacles, they may lead us to cause physical damage to our body in the form of overtraining. In this article, we will discuss overtraining and make some key distinctions in training that can help you accomplish your goals without setbacks and injury.

Overtraining
Overtraining occurs when the body is physically overloaded in such a way that the tissue fails. When I say “fails” I do not mean a tendon or muscle rupture (although that could happen), I mean failure in the sense that the muscle is used and unable to recover in a typical timeframe. Many of us have heard of the SAID principle: Specific Adaptations to Imposed Demands. What this means is that the body (and its tissues) will adapt to the specific loads applied to it. The SAID principle informs our exercise parameters (reps, sets, volume, etc.). Based on our goals, we can apply parameters to our exercise that create an optimal challenge point. This challenge point puts sufficient stress on the body to cause positive adaptations such as increased strength or muscle mass, but not so much that we are unable to recover. Overloading occurs when the demand placed on the body is too great for it to handle.

This overload can occur in one exercise session consisting of a higher typical intensity, or over several exercise bouts with inadequate rest between sessions. As I mentioned previously, overloading does not always mean that there will be an injury. If anything, one would likely continue training in a state of overload and an injury would occur later down the line. So, how do you know if you are overtraining? Here are some signs that you may have gone too far:

• Increased pain that does not resolve within 12 hours
• Pain that is increased over the previous session, or comes on earlier in the exercise session
• Decreased ability to use the body part (fear, early fatigue, increased muscle guarding)
• Increased swelling, warmth, or redness in the injury area (rehab/injury-specific)

What about DOMS?
Excellent question! Just so we are all on the same page, Delayed Onset Muscle Soreness (DOMS) is muscle soreness that occurs long after exercise, and peaks between 24-72 hours post-exercise. It is typically associated with novel high-intensity exercise and/or heavy eccentric exercise. There are two physiological theories behind DOMS: one regarding micro-tearing of the muscle fibers, requiring more time for the muscle to recover, and the other regarding the accumulation of calcium in the muscle cells causing inflammation. Either or both mechanisms may be occurring, and (in my opinion) this speaks to the importance of post-exercise diet and recovery.

All this to say, DOMS is expected in specific training situations: new, high intensity exercise and eccentric exercise. Outside of these conditions, muscle pain lasting greater than 12 hours may be a sign of overload. In order to prevent DOMS from converting into chronic muscle pain (and therefore overtraining), ensure appropriate recovery time between training sessions and utilize a progressive, variable exercise program (see Periodization later on).

Preventing Overtraining
Overtraining can absolutely be prevented! The key is to know your body and to exercise smart. Several of the signs of overtraining are “pain.” Remember “no pain, no gain?” I used to tell my clients, “no discomfort, no adaptations.” It is important to be able to distinguish pain from discomfort. Pain is an output: your body sends sensory information to the brain, which then decides if that information is damaging to the body. If it thinks that it is, we experience pain. If it thinks that it is not, we simply note the quality of the feeling (tender, hot, cool, rough, sore, etc.).

Everyone experiences pain differently, and to get into that would be an entirely different article (or essay). The key for now, is simply to know when too much is too much before lifting that heavy weight or going on that 30-mile run. A good way to do this is to use a 1-10 rating scale, with 0 being no pain, and 10 being emergency-room pain. For a high intensity workout day, being between a 7-8/10 is perfect. Anything above that indicates too much.

A lot of overtraining occurs because of a failure to recognize the condition of the body before the exercise session. This is where rest and recovery come into play. Rest involves the time of inactivity between exercises (and sets), the time between exercise bouts, and the quality and quantity of sleep day to day. Our muscles have their own recovery timeline; it is important to allow them that time within our workouts to get the most out of each set. As a general rule, 30-60 seconds between sets should be adequate, although some people require longer based on their bodies or the intensity of their exercise. Personally, I rest until I feel like I can complete the next set +1 rep, or until my HR decreases to about 110bpm after a heavy set.
(NOTE: these rules may not apply to other individuals in the same way, they are merely provided as examples of how to read your body for rest periods).

Recovery is everything done between exercise bouts to prepare for the next workout. It includes pre- and post- workout nutrition, low intensity mobility and aerobic work, body mechanics during day to day tasks, and the other aspects of rest (time between workouts and sleep). One of the best ways to beat muscle soreness is to keep moving! After a day of heavy squats, it helps to perform bodyweight squats the next day; working through the same range of motion, but without the load gets your muscles firing without eliminating all of their resources. Sleep is another one that I could write on and on about. The bottom line is this: if your sleep is poor, your workouts will be too. There is a higher risk of injury working out on a poor night’s sleep than not. Use your rating scale to determine how intense you can go that day. If you slept really badly, consider a yoga class or a light walk-jog that day. Save your max-outs and sprints for when you are most prepared for optimal performance.

Finally, I cannot stress the importance of a smart, periodized workout program. Periodization is a big picture view of training that informs how we plan and program our workouts with respect to preparation, competition, and transition. These phases are not solely for athletes; they can be implemented for the “average gym-joe” by thinking of the competition phase as a max or a PR (personal record) week. If you do not use any outcome measures currently, I highly encourage it as a way to ensure that you are creating specific goals and meeting them.

Using periodization as a tool for programming workouts helps prevent overtraining by providing the appropriate phases, timing, and variables for desired results. The preparation phase can be used to develop improved neuromuscular performance, work capacity, and technical skills. The “competition” (or “testing” if you prefer) phase is an opportunity to assess your progress in your short term and long-term goals. The transition phase is like a cool down, but for your exercise program. This phase is typically a week or two, and can also be termed as “unloading,” or a lighter workout (65% 1RM is typical). This resets the body for the next preparation phase. Again, this is a brief intro to a huge topic that I could write books about (in fact, there is a great book out there already…see source #4). If you are interested in creating a periodized program, grab a personal trainer or a strength coach to collaborate!

We covered a lot, so here are the heavy hitters: Overtraining happens when the physical load on the body surpasses what it can recover in a reasonable timeframe. It can occur after one high intensity exercise session, or after several sessions of too high intensity or inadequate rest and recovery. Ways to prevent overtraining include being humble, knowing yourself, and exercising smart. Know your limitations, interpret what your body is truly up for, and plan your workouts to both prepare you for high intensity and to recover from it. Periodization is one way to do this and has been highly effective in athletic populations. Remember: no discomfort, no adaptations. Happy training!

Sources:

1. Tissue Injury and Repair: Application to the Phases of Rehabilitation. Lecture presented by Dr. Holly Jonely and Dr. DhinuJayaseelan. Aug 19, 2018.
2. https://en.wikipedia.org/wiki/Delayed_onset_muscle_soreness
3. https://physioworks.com.au/injuries-conditions-1/doms-delayed-onset-muscle-soreness
4. Bompa, Tudor O., and Michael Carrera. Periodization Training for Sports. Human Kinetics, 2015.

Sciatic symptoms follow a consistent pattern down the leg; typically, from the low back, through the buttocks and rear thigh, around the outside of the knee and calf into the outer edge of the foot. Not everyone has sciatica all the way to the foot; some only have symptoms in the buttocks and thigh, some just in the lower leg. We will discuss why when we talk about the neuroanatomy.

Tension on a nerve often occurs at more peripheral sites. The most common cause of tensioning in athletes is a hamstring or calf strain or injury. The sciatic nerve (and its branches) are in a “neurovascular bundle” containing the nerve, arteries, and veins feeding that particular muscle. That bundle is protected and held together by connective tissue and must be able to slide within the muscle as it is stretched and contracted. Soft tissue injuries that produce scar tissue can create “sticking points” along the track of the neurovascular bundle, which oppose sliding and force the nerve to stretch excessively.

Try this: sitting in a chair, slouch down so that your low back is rounded. Keeping your thigh parallel to the floor, extend one knee, and flex the foot of the same leg (bring your toes up toward your knee) (see Image 3). Feel a little zing into your foot? Or maybe you’re unable to straighten your knee all the way? Congratulations, you’ve experienced what it’s like to tension a nerve! [Note: feeling tension with this exercise is not pathological; we’ve simply put you in a position that provides tension to both ends of the nerve.]

Deep Dive: Nerve Irritation
Let’s quickly discuss what “nerve irritation” looks like physiologically. After the nerve root comes out of the intervertebral foramen, it splits off into several branches, leading to different areas of the body. These nerves are two-way: they can both transmit messages from the brain to the muscle, as well as messages from the muscle to the brain. The messages to the muscle are motor messages (contracting and relaxing), and the messages from the muscle is sensory in nature (muscle length, tension, pain, etc.). [This is an over-simplification, but let’s not get into all of the different types of nerves and how they work…that’s a topic for another day.]

When a nerve is “irritated,” the nerve is experiencing some sort of chemical or a mechanical stimulus that disrupts its typical function of transmitting those motor messages in a way that the muscle can respond appropriately. It may send too many stimuli too quickly, causing spasms or cramping or it may not be sending enough stimuli, causing weakness due to a reduced number of muscle fibers contracting. The sensory response from the muscle is often also compromised, and the brain interprets that signal as pain. With irritation at a site other than the nerve root, the messages being sent essentially hit a “speed bump,” although the messages may be slowed or accelerated.

Treatment and Prevention
Luckily for people with sciatica, it is treatable. Not only is it treatable, but the treatment does not need to involve intensive surgery or implanted medicinal delivery devices. There are several research studies that have found that most people who have the structural issues that compress the sciatic nerve can live pain-free even if their imaging shows a disc bulge or spondylosis. For these more centrally-sourced cases of sciatica, a physical therapist or chiropractor can treat it at the source: the spine. For peripheral sciatic pain caused by soft tissue injury, a physician or physical therapist would be preferred providers. Rehabilitation of sciatica is different for every patient depending on the cause, irritability of symptoms, and the person as a whole. Most regimens involve mobility training, strengthening, and cardiovascular exercise.

Mobility focuses on both how the nerve moves through the muscle and how individual joints move together and independently. This training allows the nerve to slide more smoothly through the muscle bellies that it is in, while also providing functional tensioning and compressing with typical movement. It is important to also strengthen the muscles that both influence the tension/compression on the nerve and the muscles that are influenced by the nerve irritation. Strength training is an indirect way of regulating nerve impulses. By working at the muscle, signals sent from the muscle can provide a calming effect on the nerve and “train” the nerve to fire appropriately.

Cardiovascular exercise is also very important, as it keeps oxygen and other nutrients circulating around the body and removes wastes. There are microscopic blood vessels that nourish our nerves and help remove any waste materials that build up. Having a healthy cardiovascular system is paramount to maintaining normal function of our nerves.

The ways of preventing sciatica are the same as treating it: stay mobile, stay strong, and take care of your heart. A quick note about mobility exercises: mobility and flexibility are similar, but I chose the word “mobility” intentionally. When most people think of flexibility, they think of performing splits and long sustained stretching. Sustained stretching can actually cause undue excessive tensioning of the nerve, so I encourage mobility exercises as a way of developing flexibility through continuous full-range movements. These movements are more specific to the sliding that occurs with that neurovascular sheath and can better prepare you for functional movements that you use every day.

So, there you have it; the [abbreviated] summary of sciatica. If you think that you may have sciatic nerve pathology, contact your physician or stop by a physical therapy office. They can screen out any potential red flags and get you on track for rehabilitation. If you have concerns about developing sciatica, I highly encourage looking into mobility exercises (#mobilityWOD, among others), and decreasing the amount of sustained stretching performed on the lower extremities and back. Our bodies are amazing at regenerating and repairing; so don’t be nervous and get moving!

Sources:

1. Boxem KV, Cheng J, Patijn J, et al. 11. Lumbosacral Radicular Pain. Pain Practice. 2010;10(4):339-358. doi:10.1111/j.1533-2500.2010.00370.x.
2. Delitto A, George SZ, Dillen LV, Whitman JM, et al. Low Back Pain: Clinical Guidelines. J Orthop Sports Phys Ther. 2012;42(4):A1-A57
3. Tarulli AW, Raynor EM. Lumbosacral Radiculopathy. Neurol Clin. 2007;25(2):387-405
4. Rydevik B, Brown MD, Lundborg G. Pathoanatomy and pathophysiology of nerve root compression. Spine. 1984;9(1):7-15.
5. https://www.physio-pedia.com/Sciatica

These risk factors will make more sense as we delve into the anatomy and pathology of plantar fasciitis, and we will also talk about different ways to deal with and prevent plantar fasciitis in this article. Let’s get to it!

Plantar Fasciitis
Let’s break down “plantar fasciitis”: plantar refers to the foot, specifically the bottom of the foot; fascia is the term for the connective tissue that makes up the arch of the foot; -itis refers to inflammation, or irritation of tissue. There we have it: there is inflammation in the bottom of the foot, and it [typically] causes pain. Image 1 provides a visual.

All of the risk factors associated with plantar fasciitis compromise the mechanics of the foot during locomotion and create additional strain on the fascia.
The location of pain with plantar fasciitis is typically closer to the heel. This is the thinnest area of the plantar fascia, making it more susceptible to tearing when put under excessive load. It is normal for people to experience the most pain with the first couple of steps in the morning, and increased pain again during and after weightbearing activity (standing, walking, running). Symptoms can be present for six months or more, however, there are several ways to treat and prevent plantar fasciitis to decrease that time.

Treatment
There are a number of ways to treat plantar fasciitis: the most popular to do on one’s own are strengthening, stretching, and orthoses. Strengthening of the intrinsic foot muscles and calf can help with foot mechanics during gait, as well as improve ankle motion and stability. Stretching the fascia and the calf muscles are also good ways to manage symptoms, as the length of the fascia can be changed with sustained holds. This may be helpful in people with higher arches, as their fascia has additional tension that predisposes them to plantar fasciitis. Providing additional length to the tissue through controlled stretching may allow for a more optimal fascial tension during activity. Orthoses (also called “inserts”) can correct structural or functional arch deformities, and/or provide more support or absorption depending on what is required. A physical therapist or podiatrist can give appropriate shoe and orthosis recommendations.

Physical therapy is another option for plantar fasciitis treatment. Physical therapists (PTs) are equipped to accurately rule in or out plantar fasciitis as the cause of foot pain and treat it appropriately. Strengthening and stretching are typical aspects of treatment, as are various manual techniques to improve nerve function, decrease pain, and increase range of motion of the ankle and foot. When prescribed by a physician, PTs are also qualified to apply iontophoresis, a method of applying medication, in this case to the sole of the foot, through electrical current. Iontophoresis is known to be very effective when combined with taping over 6 treatments.

Conservative treatment is often effective, however there is the rare chance that surgical intervention is warranted. In such procedures, an orthopedic surgeon will “release” the plantar fascia. This “release” essentially cuts the fascia to reduce the amount of tension. While people end up with pain relief, rehabilitation is required to strengthen the muscles within the foot to make up for the loose fascia. It is common for people who have this procedure to develop arthritis in the midfoot region later in life.

Prevention
A lot of the techniques used in conservative treatment can also be used as prevention. Maintaining ankle range of motion by stretching the calves and ensuring the use of appropriate footwear and/or orthoses during weightbearing activities are simple ways to prevent plantar fasciitis and continue doing the activities you love. It is also important to utilize an appropriate training program: performing high level activity after a period of inactivity or progressing running speed or distance too quickly could lead to plantar fasciitis. PTs, and some personal trainers with experience training runners can help ensure that a running program is properly progressed.

Plantar fasciitis is a common condition experienced by the athletic population. It occurs when multiple factors compromise the mechanics of how the foot absorbs and transfers force during high intensity activity, such as running. Maintaining appropriate strength and motion and ensuring the use of well-fitted footwear and a properly progressed training program can prevent plantar fasciitis. For people in the sedentary population who experience plantar fasciitis, there is limited evidence that maintaining a BMI within the normal range will aid in reducing symptoms. While plantar fasciitis can be painful, there are several effective conservative treatments to heal the tissue and return full function in order to continue participation in desired activities.So, keep calm and run on!

Sources:

1. Martin RL, Davenport TE, Reischl SF, et al. Heel Pain—Plantar Fasciitis: Revision 2014.J Orthop Sports Phys Ther. 2014;44(11):A1-A23. doi:10.2519/jospt.2014.0303
2. Plantar Fasciitis. (2019, June 25). Physiopedia. Retrieved 23:46, July 23, 2019 from https://www.physio-pedia.com/index.php?title=Plantar_Fasciitis&oldid=215416.

Causes
So, what causes a hamstring strain? There are two mechanisms: 1) repeated excessive stress on the muscle with inadequate rest causing muscle tissue damage, and 2) a single event of maximal eccentric force that is surpasses the mechanical limits of the muscle. The repeated stress mechanism can be explained by typical muscle physiology. Every time a muscle is exercised, there is microdamage to the muscle fibers. Usually, this is a good thing; the microdamage signals the body to repair and grow/strengthen the muscle. A strain is possible when the body does not have enough time between bouts of exercise to repair the area. The repetitive microdamage to the same muscle leads to more muscle breakdown than building, and the muscle becomes painful and possibly weaker.

There were a lot of big words in the second mechanism, so let’s break it down. Our second mechanism is a single traumatic event; it happens in one moment. Eccentric muscle contraction is controlled lengthening of a muscle. In the hamstring, eccentric forces are placed on the muscle at the end of swing phase: the hamstring controls knee extension (straightening) before you put your foot on the ground to take a step. It is during this phase of running that the greatest eccentric force is placed on the muscle. The faster the speed, the greater the force. A strain occurs when the eccentric force placed on the muscle is too much for it to handle. When this happens, the muscle tries to contract (shorten) to protect itself, and the opposing forces cause the muscle to tear.

Risk Factors
There are some predisposing factors to hamstring strains, including insufficient warm up, decreased core strength, and muscular imbalance between the quadriceps and hamstrings. Warming up is extremely important before any athletic activity. Cold muscles are more easily torn due to stiffness; warming up with a light jog or brisk walk or mobility exercises can help with muscle function during exercise. When the core is weak, other areas of the body make up for it–especially the hip musculature. Both the hamstrings and quadriceps attach on the pelvic bone and can be used to compensate for a lack of stability in the core. This compensation is achieved by those muscles contracting more frequently and becoming tight over time. Sometimes the quadriceps and hamstrings have a strength imbalance, which means that one is stronger than the other. Because these two muscles perform opposing actions (quadriceps do hip flexion and knee extension, hamstrings do hip extension and knee flexion), one must lengthen when the other contracts. A person with stronger and tighter quadriceps is at higher risk for a hamstring strain because a powerful quadriceps contraction could contribute to the super-maximal eccentric force placed on the hamstrings. Utilizing a strengthening program that adequately loads both muscle groups is a great way to prevent this risk factor.

We will get into some other prevention and rehabilitation techniques for hamstring strains and IT band syndrome after both have been discussed. Let’s get into IT band syndrome!

IT Band Syndrome
IT band syndrome is the most common cause of lateral (outside) knee pain in runners. We briefly touched on the IT band in the introduction, but let’s talk more about what it is and what it does. The iliotibial (IT) band is a thick band of fascia (connective tissue) that originates from the tensor fascia latae muscle and attaches on the lateral tibia (the outside of your shin bone, just below the knee). The tensor fascia latae (TFL) is located on the front of your hip. You can find it by locating the pointy bones on the front of your hip and then moving your fingers down and slightly outward. That muscle bulk should become firm when you turn your foot inward. The TFL and IT band are related in that when the TFL is tight, it puts tension on the IT

Risk Factors
There are a number of structural and functional reasons why IT band syndrome occurs in some people and not in others. Structural causes are not able to be changed through rehabilitation, such as bony anatomy. The major structural risk factor for developing IT band syndrome is an externally rotated femur (in some people it shows up as toe-ing out). Basically, the thigh bone is rotated so that the IT band comes in contact with a greater area of the femur and is therefore put on more tension. More women are susceptible to this based on their pelvic anatomy and the angle of the hip joint, however it may also be seen in men.

Functional risk factors can be modified, typically through stretching or strengthening of the surrounding muscle(s). Examples of these are quadriceps/hamstring imbalances, excessive strength of inner thigh muscles, or abnormal foot/ankle mechanics during running. We discussed quadriceps/hamstring imbalances with hamstring strains above, so I’ll explain the other two a little more. The inner thigh muscles work to bring your legs together, an action called adduction. If these muscles are overactive, they cause an extra internal rotation and inward force on the femur, which tensions the IT band. The ankle and foot relate to knee pain in that any abnormal motion there is compensated for at the hip and/or knee. For example, if a runner has trouble clearing their foot, they are likely to compensate with greater knee and hip flexion to avoid tripping. The extra work given to the knee and hip places greater stress on both the TFL and the IT band, predisposing the runner to IT band syndrome.

Prevention and Rehabilitation
As stated previously, the best way to prevent injuries is to provide the muscle(s) of interest with an adequate warm up and cool down. Preparing the muscle for training or sport is equally as important as performance. A proper cool down and recovery allows the involved tissues to repair and become stronger over time. Along with good practice habits, an appropriate, progressive strengthening program is beneficial to any and all athletes. Intentional strengthening of muscles can reduce imbalances and promote more efficient use of energy systems by the muscle.

Including mobility exercises in your training regimen will contribute to smooth joint and nerve movement during activity. If a joint is limiting motion, the muscle may not be able to work in an optimal range, putting it at risk for injury. Nerves travel in bundles through muscles, and slide within a sheath during movement. Nerve compression from tight muscles can perpetuate muscle pain and tightness, so moving through complete ranges of motion can keep those nerves gliding smoothly.

One more caveat when it comes to core strengthening: we discussed how important it is for the core to stabilize in order for the hip musculature to function as intended and avoid compensation. Remember to also practice spinal mobility. All nerves to the extremities originate at the spine, and if your spine is not moving well, you are more likely to have problems there that could refer down into the limbs.

If you or someone you know experiences one of these injuries, set up an appointment with a physical therapist. With conservative treatment, most people with hamstring injuries can return to play in 16-50 weeks (depending on severity), and people with IT band syndrome can return to play in 6-8 weeks. For the best injury prevention, stay strong, stay mobile, and recover well. For the best rehab, reach out to a professional to discuss a treatment and a progressive program to return to your activity.

Sources:

1. Hamstring strain. In DynaMed Plus [database online]. EBSCO Information Services. http://www.dynamed.com/login.aspx?direct=true&site=DynaMed&id=116919. Updated March 30, 2018. Accessed September 2, 2018.
2. Hamstring strain. Physiopedia website https://www.physio-pedia.com/index.php?title=Hamstring_Strain&oldid=197355. Updated August 30, 2018. Accessed September 2, 2018.
3. Iliotibial Band Syndrome. Dynamed. http://www.dynamed.com.proxygw.wrlc.org/topics/dmp~AN~T116225/Iliotibial-band-ITB-syndrome#Overview-and-Recommendations. Accessed August 28, 2018.
4. Iliotibial Band Syndrome. Physiopedia. https://www.physio-pedia.com/Iliotibial_Band_Syndrome. Accessed August 28, 2018.
5. Saika S, Tepe R. Etiology, Treatment and Prevention of ITB Syndrome: A Literature Review. Topics in Integrative Healthcare. 2013; 4(3). http://www.tihcij.com/Articles/Etiology-Treatment-and-Prevention-of-ITB-Syndrome-A-Literature-Review.aspx?id=0000406. Accessed August 28, 2018.
6. Iliotibial Band Syndrome. Clinical Key. https://www.clinicalkey.com/#!/content/clinical_overview/67-s2.0-44925320-1d10-452e-a169-42bb30de0c36. Accessed August 28, 2018.

It is important to understand that the rotator cuff muscles are the only contractile tissues stabilizing the humeral head, which means that they are the only structures that can actively react to changes in shoulder position. The labrum and the ligaments can stretch to accommodate movement and have an elastic quality that allows them to ‘rebound’ to their original length, but this is not the same as a muscle contraction. Understanding this distinction sheds light as to how overuse injuries occur.

Overuse Injuries
There are two major overuse injuries that occur: shoulder impingement and rotator cuff tears. Both can be caused by traumatic events as well, but we will focus more on overuse or repetitive movements as the cause of dysfunction.

Not only should the rotator cuff be trained, but other muscles controlling the shoulder should be adequately strengthened as well. The pectoralis, latissimus, rhomboids, and trapezius play a role in how the shoulder stabilizes and moves. It is important to train both for strength as well as motor control, as these muscles tend to be the ones that compensate for weak rotator cuff muscles.

The three most common exercises for the rotator cuff and shoulder stability are 1) external rotation, 2) empty cans, and 3) serratus or shoulder pushups (see Image 5 below).

Depending on severity, people receiving care for overuse injuries can return to normal activities in about four to six months. Tendons and ligaments may take up to 10-12 months to return to 90% of their original strength, so patients should continue to rehabilitate even after discharge from physical therapy and return to prior level of function gradually.

Rotator cuff injuries are common in all age groups and can have a serious impact on arm function and quality of life. Prevention through appropriate exercise and a healthy lifestyle are integral for anyone participating in repetitive and/or overhead activities. If someone does sustain an injury, physical therapy (and sometimes surgery) can get them back to function in a reasonable amount of time. These injuries are some of the most commonly researched and treated, and health professionals are more than prepared to treat any dysfunction. The key is to work on prevention strategies and check in with a health care provider at the first suspicion of dysfunction. Now, who’s up for a game of catch?

Sources:

1. Codsi M, Howe CR. Shoulder Conditions. Physical Medicine and Rehabilitation Clinics of North America. 2015;26(3):467-489. doi:10.1016/j.pmr.2015.04.007.
2. DynaMed Plus [Rotator Cuff Impingement]. Ipswich (MA): EBSCO Information Services. http://www.dynamed.com. Accessed October 10, 2010
3. Oliva F, Piccirilli E, Bossa M, et al. I.S.Mu.L.T – Rotator Cuff Tears Guidelines. Muscles, Ligaments and Tendons Journal. 2015;5(4):227-263. doi:10.11138/mltj/2015.5.4.227.
4. Sambandam SN, Khanna V, Gul A, Mounasamy V. Rotator cuff tears: An evidence based approach. World Journal of Orthopedics. 2015;6(11):902-918. doi:10.5312/wjo.v6.i11.902.
5. Breazeale, N M (04/1997). “Partial-thickness rotator cuff tears. Pathogenesis and treatment.”. The Orthopedic clinics of North America (0030-5898), 28 (2), 145.
6. Kadi R, Milants A, Shahabpour M. Shoulder Anatomy and Normal Variants. Journal of the Belgian Society of Radiology. 2017;101(S2):3. doi:10.5334/jbr-btr.1467.