The navicular bone is one of the 28 bones in our foot. It is important for connecting the ankle to the lower bones in our feet and helps form the arch that enables us to walk. A navicular stress fracture is a hairline crack in the bone which develops gradually over time. These stress fractures tend to occur in athletes whose sport requires intensive movements and sudden changes in direction.
Anatomically, the navicular bone is designed with a few sets of problems that make it particularly susceptible to stress injury. One of these problems is the location of the bone. Located in the middle of the foot, high compressive forces are focused on this specific bone when the foot strikes the ground.
The second problem is the blood supply to the navicular bone, particularly the central area of the bone where these stress fractures occur. This area is known as the watershed zone where the blood supply is less robust, making the recovery of minor injuries much more difficult and therefore a higher rate of developing a stress fracture.
Causes & Symptoms of a Navicular Stress Fracture
While anyone can sustain a navicular stress fracture, there are certain activities that increase the likelihood of the injury occurring. As the name suggests, navicular stress fractures can occur from any activity that puts too much stress on the navicular bone, such as a new workout routine. Other causes of a stress fracture include:
- Sudden increase in activity – This increase can be in the duration or intensity of an activity. For instance, an athlete training for a marathon may increase mileage rapidly, which can be difficult on the feet.
- Improper technique – Other foot conditions, such as blisters or bunions, may impact the way the foot strikes the ground when running or walking. You may avoid putting weight on a certain area of the foot and unintentionally cause undue stress to the navicular bone.
- Change in surface – Going from a soft surface, such as an indoor running track or turf, to a hard surface, such as concrete, can cause stress to the bones of the feet.
- Improper footwear – Shoes that are in poor condition, ill-fitting, or stiff can all contribute to a navicular stress fracture.
The most common symptom of navicular stress fractures is a persistent achiness in the arch or midsection of the foot that worsens with exercise or from prolonged standing. Oftentimes, pain can radiate along the inside edge of the foot, temporarily resolving with enough rest and recurring when activity is resumed.
Furthermore, these symptoms can often be confused with plantar fasciitis, which is a condition that occurs when the strong fibrous tissues in the arch become inflamed and irritated, developing tiny tears.
However, navicular stress fractures also tend to become associated with tenderness in the area over the navicular bone when this region is gently pressed. Plantar fasciitis also tends to cause symptoms along the bottom of the foot, including burning sensations that tend to differ from the aching associated with a navicular fracture.
Other symptoms linked to navicular stress fractures include:
- Swelling – The injured foot may appear swollen with a visible bump where the navicular bone is located.
- Bruising – The area around the fracture may appear red, blue, or purple in color because of blood rushing towards the injury.
- Changes in biomechanics – You may notice running or walking differently while you try to avoid putting pressure on the painful area.
- Weakness – The midsection of the foot may feel weak and regular performance may be diminished.
Who gets a Navicular Fracture?
Certain risk factors increase the likelihood of developing a navicular stress fracture, including the following:
- Previous fracture – Having a previous foot stress fracture increases the risk of developing another stress fracture, including the navicular bone.
- Gender – Female athletes are at an increased risk of developing a navicular stress fracture. This may be due to a number of factors including female biomechanics, nutrition, and hormone levels. Additionally, females with irregular menstrual periods may be at an even higher risk of experiencing a stress fracture.
- Weight – Excess weight can put added pressure on muscles and bones, wearing them down faster. Someone who is underweight may lack muscle and bone strength, making them more susceptible to navicular stress fractures.
- Sports activity – Participation in high-impact sports, such as running, soccer, basketball, and dancing can increase the chances of sustaining a stress fracture in the navicular bone.
- Lack of nutrients – Eating disorders and lack of vitamin D and calcium can make bones more likely to develop navicular stress fractures.
- Weakened bones – Low levels of vitamin D can decrease bone density and strength, which may result in an increased chance of experiencing a navicular stress fracture.
How Does a Navicular Fracture Affect You? How Serious is it?
Stress fractures in general typically heal with adequate rest and treatment (with an estimate of 6-8 weeks). However, complications may occur if you continue to push through the pain or do not allow enough time to recover before returning to activities.
This includes nonunion healing (incomplete) and malunion healing (abnormal). These can result in chronic pain and disability. You may also experience complete or repetitive fractures if left untreated. When a navicular stress fracture continues to occur, osteoporosis may be the cause.
Recommended Treatment, Rehabilitation for a Navicular Fracture
In order to receive an accurate diagnosis for navicular stress fractures, a physician will need to know your complete medical history as well as any known risk factors that might have been the result of the condition.
In cases of recurring stress fractures, your physician may order a complete medical work-up, which includes blood tests to help determine if nutritional deficiencies, such as low Vitamin D, may be a factor in the fracture.
Following the interview, your doctor may perform a physical exam to confirm the diagnosis of a navicular stress fracture. Usually, this is a simple examination in which your doctor applies pressure to the navicular bone; if pain or tenderness is felt due to the pressure, a stress fracture is likely the cause.
After a patient interview and physical exam are performed, your doctor may order additional diagnostic imaging to rule out other conditions. Therefore, one or a combination of the following imaging tests may be used to confirm the diagnosis of a navicular stress fracture:
- X-ray – X-rays are normally the first imaging tests that are performed. However, stress fractures are often difficult to see on X-rays immediately following the injury and may only be noticeable once the injury has begun to heal. X-ray imaging may be repeated after some weeks if a fracture is suspected but was not initially visible.
- Ultrasound – This is a sensitive test that can detect stress fractures in superficial bones, such as the bones of the feet.
- Magnetic resonance imaging (MRI) – An MRI uses a powerful magnetic field and radio waves to show a detailed view of the soft tissue surrounding the bone. It can be used to identify abnormalities surrounding a navicular stress fracture.
- Bone scan – A bone scan uses a radioactive substance (tracer) that is injected into the bloodstream and a special scanner, which can detect the substance and produce pictures of bones. A stress fracture will appear darker on a bone scan when compared to an uninjured area.
Once a diagnosis has been done, physiotherapy may be further advised. A physiotherapist will work with you by designing an individualized treatment program for you, based on your condition and goals. Your treatment may include:
- Range-of-motion exercises – Because you have been less mobile over the past few weeks following a navicular stress fracture, your range of motion may have decreased. Your physiotherapist will teach you how to perform safe and effective exercises to restore full movement in the joints of your feet.
- Muscle-strengthening exercises – Your stress fracture may have been related to some underlying weakness in the foot. Therefore, your physiotherapist can determine which strengthening exercises are perfect for you based on the severity of your injury and where you are in your overall recovery.
- Balance training – When you are able to put your full weight on your foot without pain, your physiotherapist may prescribe these training exercises to help you return stronger to your regular activities.
- Orthotic therapy – In-shoe orthotics may be beneficial to support your return to activity with no pain as well as possibly prevent future stress fractures.
- Patient education – Proper shoe selection, nutrition, training regimens, and other topics are an essential part of your rehabilitation. Your physiotherapist will provide specialized education to aid in your recovery as well as in the prevention of future foot injuries.
The following below is a list of a few exercise methods you can try to help boost your recovery from a navicular stress fracture:
Toe raise, point, and curl
Sit up straight in a chair, with the feet flat on the floor. Keeping the toes on the floor, raise the heels. Stop when only the balls of the feet remain on the ground. Hold this position for 5 seconds before lowering the heels. For the second stage of this exercise, raise the heels and point the toes so that only the tips of the big and second toes are touching the floor. Hold this position for 5 seconds before lowering. For the third stage, raise the heels and curl the toes inward so that only the tips of the toes are touching the floor. Hold this position for 5 seconds.
Sit up straight in a chair, with the feet flat on the floor. Then, lay a small towel on the floor in front of the body, with the short side facing the feet. Place the toes of one foot on the short side of the towel. Try to grasp the towel between the toes and pull it toward oneself. Repeat this exercise five times before switching to the other foot.
Big toe stretch
Sit up in a chair, with the feet flat on the floor. Bring the left foot to rest on the right thigh. Using the fingers, gently stretch the big toe up, down, and to the side. Finally, keep the big toe in each position for 5 seconds. Repeat this 10 more times before switching to the other foot.
Sit up straight in a chair, with the feet flat on the floor. Place an empty bowl and a bowl of 20 marbles on the floor in front of the feet. Using only the toes of one foot, pick up each marble and place it in the empty bowl. Repeat this method using the other foot.
Face a wall and raise the arms so that the palms of the hands are resting flat against the wall. Move one foot back, keeping the knee straight, then, bend the knee of the opposite leg. Keep both heels flat on the floor. Afterward, push the hips forward until there is a stretching feeling in the Achilles tendon and calf muscles. Hold for 30 seconds before switching sides. Repeat three times on each side.
Alternative & Homeopathic Treatment for a Navicular Fracture
Here are some home remedies for foot pain that will work for your healing process regarding this condition:
- Rest – The person should stay off the injured foot. Walking, running, or playing sports could increase the injury and worsen.
- Ice – The patient should apply an ice pack to the injured foot as soon as they can. For the first 48 hours, he/she should repeat this step throughout the day, for 15-20 minutes at a time.
- Compression – The individual should wrap a bandage around the injured foot and ankle. The bandage should be snug, however, the patient will need to be careful not to cut off his/her circulation.
- Elevation – It is recommended to lie down and elevate the injured foot so that it is above the heart. This will decrease the swelling.
- Apply a foot cast – This helps keep bones in a fixed position while they heal and to reduce stress on the affected leg.
- Protective footwear – such as a removable walking boot can reduce stress on your injured foot.
- Non-steroidal anti-inflammatory medications (NSAIDs) – such as ibuprofen, naproxen, or acetaminophen, can help reduce pain and swelling located in the midsection of your foot.
- Vitamin supplements – such as Vitamin D or calcium, may help boost your recovery if the stress fracture occurred because of a nutrition deficiency.