Pes planus, also known as flat feet, refers to a foot posture in which one or both feet have a low or absent arch.
This is related to overpronation, a foot movement that causes the tibia, femur, and pelvis to internally rotate and tilt forward.
When this abnormal foot posture affects the entire kinematic chain, it increases the risk of musculoskeletal complications, affecting muscle movement, gait, and the impact of ground reaction forces.
One potential complication of flat feet is lower back pain, which can significantly impact an individual's health and quality of life, even making it difficult to perform daily activities.
Symptoms of lower back pain include pain, muscle tension, and stiffness.
Flat feet have been identified as an important risk factor for low back pain, as the abnormal foot posture can contribute to misalignments in the body's overall structure.
However, it is important to note that other factors can also aggravate lower back pain symptoms.
Flat feet can cause uneven weight distribution when walking, standing, and running.
This can cause one side of their shoes to wear out faster and be more comfortable than the other.
Along with back pain, people with flat feet may also experience tired or achy legs after standing or exercising for a long time.
Dysfunction in the foot arch can affect not only the lower limbs and lumbar spine, but also the upper body, increasing the risk of pain and injury.
You might be wondering how foot posture affects back pain. When we walk, we put a lot of force on our feet - up to five times our body weight!
Our feet should absorb that shock or spread it out evenly to avoid problems elsewhere, and the arch is responsible for this.
But for people with flat feet or overpronation, where the ankle rolls too far inward, the foot can't absorb the shock properly.
This lack of stability in the foot causes our bodies to compensate in other ways, which can put extra pressure on other parts of our body, like the lower back.
Overpronation can cause our legs to turn inward, which affects the alignment of our knees, hips, and pelvis, putting more strain on our lower back.
Additionally, individuals with flat feet may alter their posture to balance themselves and reduce foot pain, resulting in compensatory patterns between their legs and spine.
This can lead to an uneven distribution of weight on both sides of the body and misalignment of the spine.
Weak muscles due to overcompensation in other leg muscles can also contribute to how flat feet cause lower back pain.
This can lead to muscle frailty in the calf and ankle areas, making it harder for our legs to act as shock absorbers and putting more strain on our lower back.
To start, it's important to determine if your back pain is actually related to your foot function.
If it is, your healthcare provider may recommend a conservative treatment approach, such as using supportive orthotics like insoles or custom-made shoes to provide cushioning and arch support.
These orthotics can also help to alter foot posture, leading to changes in the lower limb and pelvis that affect musculature patterns.
Physical therapy may also be suggested to improve foot muscle function with exercises to strengthen and stretch intrinsic muscles responsible for the arch.
Correcting the dynamic posture of the foot, which means encouraging more supination and alignment, is also part of rehabilitation.
The good news is that treatment options for this type of back pain are relatively straightforward as long as the root cause is addressed early on.
When to see a doctor
To diagnose the root cause of back pain, medical professionals use various scanning and imaging techniques.
If treating flat feet through orthotics and physical therapy does not alleviate back pain, it is recommended to consult pain management doctors or orthopaedic specialists who can develop customised plans for symptom relief.
In some cases, surgery may be necessary to correct flat feet and address associated back pain.
To sum up, flat feet can be a bigger problem than it seems, leading to lower back pain and potentially developing into chronic conditions if left unattended.
It's important not to overlook the issue and take action early on to correct misalignment.
Investing in proper footwear or foot orthotics can make a significant difference in preventing and treating this type of pain.
Certified Physiotherapist for Shoulder and Knee Injuries
Inês is a skilled physical therapist with a special interest and extensive experience in working with athletes, specifically football players and also neurologic patients.
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