Dr. Erin Coughenour PT, DPT, SCS, RYT

09/19/2025

This article makes me giddy with excitement 🤗 What a well-written explanation of the science of contractile tissue, relative stiffness, and neuromuscular consequences and adaptation via the lens of material mechanics.
Anyone familiar my style of movement assessment, knows I utilize muscle testing in order to create a picture of neuromuscular function, muscular inhibitions, and compensatory movement strategies that alter force distributions and lead to musculoskeletal pain.
This article describes the scientific basis for my assessment approach as well as the reasoning behind my treatment approach, through the lens of material mechanics! Sometimes my assessment and treatments seem like magic, but they're really not. They're rooted in the movement science.

https://aifimm.it/en/a/biomechanics-causes-muscle-shortening?fbclid=IwdGRjcAM6MIJleHRuA2FlbQIxMQABHk8V16ZVkVYZKz8687X7yh2kPugtUuQqihsz7TTysmrAaOs9xfztBE05TdMD_aem_7Wy3aHVWk4WlxZYijXUDSA

Biomechanics: causes of muscle shortening

01/11/2025

This is a video of a neurosurgeon discussing why he decided to quit his job performing spinal surgeries.

The answer- Spinal surgery often doesn't help because it doesn't actually address the root cause of the problem.

In this video, the surgeon explains the factors he observed that helped to determine whether someone actually got better, even before surgery was ever performed.

These factors include aspects of health that relate to physiological health, including nutrition, stress management, and an active lifestyle.

These factors are important because they impact the tissues capacity for healing, adapting, and thriving. The factors he describes also tend to support better musculoskeletal functioning from a general sense. A healthier body has a better capacity for healing, as well as better tools to support quality movement.

I have spent my 16 year career studying the root causes of musculoskeletal pain, and have had years of experience helping people who have failed surgeries, or helping people avoid surgeries.

There are a couple concepts that are important to understand further when considering the root cause of musculoskeletal pain.

1) Physiological Health

Physiological health (including the factors the neurosurgeon describes in his video) is not only essential for tissue healing capacity, but also impacts how the neurological and musculoskeletal systems work. In other words, physiological health can impact how the neuromuscular system is able to create stability and mobility. For example, if someone is acutely dehydrated, their physiology is not optimal to produce the neuromuscular stability required for optimal movement or even static postural stability and support. The number of physiological factors that can influence neuromuscular system function are as vast as the body is complex.

2) The Neuroimmune Axis.

The neuroimmune axis describes how the neurological system works together with the immune system. This synergy can determine not only the pain threshold, but the effectiveness of the inflammatory and healing response. It is important to assess the contributions of this factor in the overall understanding of the root cause of musculoskeletal pain. The neuroimmune axis can be highly affected by the state of the nervous system as it relates to stress. Stress drives the stress response in the body, which is essentially carried out by the sympathetic nervous system (aka fight or flight system.) The parasympathetic nervous system (aka rest and digest system) function is essential for recovery and healing. The immune system is deeply integrated with the nervous system. The inflammatory response is essential for healing. But when the nervous system is out of balance (sympathetic nervous system overdrive), the immune system can get stuck in a hyper inflammatory/pain sensitive state, without the ability to complete the healing cycle, which requires the rest, digest, and recovery magic of the parasympathetic nervous system (which is suppressed during sympathetic nervous system overdrive.)

3) Mechanical Factors in Musculoskeletal Pain

Lastly, I need to address the mechanical factors involved in musculoskeletal pain, as these factors are the ones I primarily address in my physical therapy practice. The body’s ability to create stability and mobility determine how force is distributed through the body. Appropriate mobility is crucial for force distribution and determines how much force is distributed through which tissues at any given time. Any given tissue has a certain capacity to absorb force. The body is incredible in its ability to heal, adapt, and strengthen, but there comes a threshold where force load capacity for a tissue is exceeded, healing capacity is breached, and tissue breaks down.

The body is designed to distribute forces so that no one tissue breaches its capacity to absorb stress. But when stability mechanisms and mobility are compromised (often seen when the body relies heavily on a limited number of compensatory movement strategies) excessive forces can be imparted to isolated areas, causing tissue stress overload and breakdown, leading to structural degradation and chronic pain.

Optimizing force distribution, by optimizing stability and mobility, (therefore increasing the number of efficient movement strategies) is an essential component of resolving musculoskeletal pain and optimizing musculoskeletal function and performance. Diagnosing the root cause of pain requires an ability to assess whole body movement and force distribution patterns. Assessing, diagnosing, and restoring optimal force distribution is the core of my physical therapy practice, and absolutely key to maintaining healthy joints and tissues.

In conclusion, the neurosurgeon is absolutely right. The tools he has learned often do not address the root of the problem. Spinal surgery can certainly be a helpful and essential tool in certain cases, but thinking it is the ultimate solution can often be misguided. True healing requires addressing the underlying factors; physiological health, neuroimmune function, and mechanical factors. By addressing these root causes we can achieve sustainable pain relief, improved quality of life, and enhanced performance, not to mention, avoid surgeries.

Here, I share my story about how I spent the last two decades of my life as a neurosurgeon who went through a mid-life crisis and got through to the other si...

03/10/2024

Plantar fasciitis is one of the most common musculoskeletal complaints I get questions about. In this post, I address the underlying causes and treatment approaches.

Plantar fasciitis is one of the most recalcitrant musculoskeletal conditions. It's natural course can be around 8-18 months, per the medical literature.

There are often multiple factors that contribute to excessive loading of the plantar fascia that lead to chronic inflammation. Usually what I find is:

1. Loss of balance and core control, resulting from joint restrictions and muscular imbalances in the lumbar spine and pelvis. This is not something people generally notice because the body is very good at compensating, but the result is excessive reliance on the ankle strategy for balance control and creates excessive demands on the plantar structures.

2. Increased loading of the affected leg. This is also the result of the restrictions and imbalances occurring in the pelvis and lumbar spine, combined with compensatory movement strategies that result. In this case, strength and stability of the opposite leg is inhibited, resulting in a compensatory shift of weight and function to the affected leg, resulting in excessive loading of the plantar structures.

3. A breakdown of the mechanics of the affected leg. The above factors result in excessive loading of the affected leg, which will put excessive demand on the gluteus medius, which is a very important muscle for pelvic control during gait. The gluteus medius becomes overused, weak, and fatigued. This results in a lateral hip drop. That lateral hip drop results in adduction and internal rotation of the femur, which then puts excessive pronation force through the arch of the foot, further loading the plantar foot structures. The tibialis posterior is a muscle that normally controls pronation, however, similar to the gluteus medius, it gets excessively used, fatigued, and weak. Because that muscle gives out, pronation is uncontrolled, and the plantar structures are strained.

4. Loss of adequate dorsiflexion of the ankle. This is often a contributor of plantar fasciitis. When the ankle is restricted from moving into dorsiflexion, the midfoot is forced into excessive pronation because the body moves in the path of least resistance. Adequate dorsiflexion must be restored in order to remove that excessive pronation force. Restricted dorsiflexion can be the result of both talocrural joint restriction, and muscular restriction from the gastrocnemius and soleus. (Excessive muscular tightness in the gastrocnemius and soleus is often a result of the above factors, including increased reliance on the ankle strategy for balance control, and overuse of the affected extremity based on compensatory patterns.)

5. Gross ankle instability. Ankle joint restrictions can contribute to an overall loss of ankle joint stability. Hypermobility, either inherent, or as a result of ankle sprain, can contribute to ankle instability. Lack of control at the ankle will result in excessive loading of the foot plantar structures.

6. Weakness of the plantar musculature. The plantar muscles often become overused from the excessive demand and become fatigued, weak, tight and sore. Any muscle group under such chronic excessive demand would react this way. The insertion of the plantar aponeurosis becomes chronically inflamed.

7. Foot structure can also play a role in the loading of the plantar fascia. High rigid arches are at increased risk for excessive plantar fascia loading, however flexible arches present with plantar fascia issues as well. Due to the flexibility, the first ray, or first metatarsal of the foot, may be relatively dorsiflexed, compromising the integrity of the foot arch structure, which results in further strain of the soft tissue plantar structures.

I believe that plantar fasciitis is so typically recalcitrant because of the number of factors involved. In order to most efficiently treat and resolve plantar fasciitis, all factors contributing to excessive plantar loading need to be addressed. When all factors are addressed, resolution can occur within a matter of weeks.

The solution:

1. Restore mobility, muscular balance and control of the lumbopelvic region. The treatment may be individualized based on the contributing factors which may include restriction of the SI joint, compression of the lumbosacral region, loss of extension mobility of the lumbar or lumbosacral joint, as well as muscular inhibition that can result from various factors and require various treatment interventions.

2. Restore stability and function of the opposite leg. Some of the intervention may include factors from number 1. Some of the intervention may include addressing the hip joint or musculature.

4. Restore the stability and control of the affected leg. This can include myofascial release techniques (a tight, contacted, overused muscle does not contract well, and in this case may need muscle release techniques.) Muscular facilitation and strengthening exercises can also be used.

5. Restore ankle dorsiflexion range of motion through ankle mobilization and muscular release as needed.

6. Restore ankle stability, including necessary mobilization or muscular facilitation.

7. Restoring function of muscular plantar structures, including myofascial release of the plantar structures. This can be done with rolling a ball under the foot. Strengthening exercises can also be done to facilitate plantar muscle function and tibialis posterior control.

8. Restoring or supporting the foot arch. This can be done by mobilization of the foot if necessary, and strengthening of the musculature. However, this can also be passively supported with orthotics, and or taping methods, which is a good interim method of offloading plantar structures.

*You will see options such as night splints which can help to address dorsiflexion restriction of the ankle, but only the muscular tightness contribution. It does not solve the underlying reason for the muscular tightness, nor adequately address restrictions of the joint. But it can help to offload the plantar structures temporarily and may help with the typical morning pain by keeping muscles lengthened overnight.

Typical treatments of plantar fasciitis tend to be unsuccessful because they only address one or two of the contributing factors above. Typical treatments provided by a podiatrist may be a night splint, orthotics, maybe myofascial release of the plantar fascia with a golf ball, icing, and if that doesn't work often steroid injection. These interventions can be enough depending on the individual. The steroid injection does nothing to solve the underlying problem except shut down the inflammatory response, though it can be a useful tool in some circumstances.

Again, addressing all the factors contributing to the problem will result in the most effective outcome. Addressing one or two factors will result in a hit or miss outcome, depending on the individual. Individual factors can include things like overall health, blood and tissue oxygenation, tissue health, metabolic health, daily physical demands, body weight, how many factors are involved etc.