https://immattersacp.org/archives/2017/06/feet.htm

Relax, kick off your shoes, and examine common foot disorders

To diagnose foot pain, start with its location, hindfoot, midfoot, or forefoot, according to one physician who treats military members and other high-performance athletes.


Joan Bowes Ritter, MD, FACP, a general internist at Walter Reed Medical Center in Bethesda, Md., said she sees more than her share of soldiers and sailors—people who “exercise for a living” and are often also highly motivated athletes who push themselves in high-impact sports such as running, tennis, or the martial arts. These activities take a toll on their feet.

The lessons she has learned from diagnosing these patients apply to all her patients, she said, including the families of the military patients and the general population, whom she also treats. “There are some easy things that you can do as an internist” to make the correct diagnosis among the many maladies that can affect the feet, she said.

Joan Bowes Ritter, MD, FACP, advised starting with the location of the pain to make a correct diagnosis among the many maladies that can affect the feet Photo by Kevin Berne
Joan Bowes Ritter, MD, FACP, advised starting with the location of the pain to make a correct diagnosis among the many maladies that can affect the feet. Photo by Kevin Berne

Dr. Ritter delivered her talk, “Best Foot Forward: Common Foot Complaints That Walk into the Office,” at Internal Medicine Meeting 2017.

To diagnose foot pain, start with its location, Dr. Ritter said: hindfoot, midfoot, or forefoot (with special attention paid to the first metatarsal phalangeal joint).

Hindfoot pain

Dr. Ritter sees heel pain in runners, mostly—people who increase the intensity or duration of their running too quickly, usually in preparation for a marathon. Most have Achilles tendinopathy. In these cases, separation of tendon fibers results in inflammation and potentially calcification. A physical exam shows tenderness over the tendon at its insertion at the superior portion of the calcaneus. A simple heel lift can take pressure off the injury, but patients are going to have to rest, which runners are often not willing to do.

Proper rehabilitation and prolonged rest will help with recovery. A temporary boot may also be appropriate. But, she warned, acknowledge that the patients are going to be angry in the meantime.

“This is going to be like the stages of death and dying,” she said. “They are going to be in denial. In fact, they've probably been in denial.” Some patients are training for once-in-a-lifetime experiences, such as the Boston Marathon. Others might be self-treating anxiety or depression with exercise. “Giving them something else to do, like swimming or aqua-jogging, is really important,” she noted.

Dr. Ritter expands on counseling highly-motivated athletes in the following video.

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To further diagnose posterior heel pain, Dr. Ritter said to consider the differential diagnoses of Haglund's deformity, retrocalcaneal and subcutaneous bursitis, or a calcaneal stress fracture.

Haglund's deformity is exostosis that develops in the superior portion of the calcaneus. It is more common in runners and in women. Upon examination, there is pain, tenderness, and a “bump” at the superior calcaneus. An X-ray may show a prominent posterior superior calcaneus.

Treatment involves icing the area several times a day for 15 to 20 minutes, doing exercises to stretch the Achilles tendon (wall stretches with knee straight and flexed), and wearing open-backed shoes. A one-inch heel lift can move the foot load forward and raise the back of the foot above the irritation (put the lift in both shoes to keep leg length even, she noted). NSAIDs may offer inflammation and pain relief, while steroid injections are not generally recommended due to a risk of Achilles tendon rupture. Surgical resection offers mixed results, she said.

The risk factors for retrocalcaneal and subcutaneous bursitis include high-heeled shoes and overtraining. These conditions are associated with gout, rheumatoid arthritis, and seronegative spondyloarthropathies, so physicians can consider serologic testing for rheumatologic disorders.

Treatment involves many of the same techniques used for Haglund's deformity, but physicians can also consider offering a walking boot or cast for four to six weeks, Dr. Ritter said.

Calcaneal stress fractures are associated with marching, running, jumping, and ballet dancing. “These are not terribly common but may be something to consider in your diagnosis,” said Dr. Ritter.

Signs and symptoms may be similar to those of other stress fractures: more diffuse pain than plantar fasciitis, insidious onset, and initial negative X-rays. Treatment involves modifying activities, and a walking boot may be necessary to control pain with walking. Evaluate the patient's bone health, she advised, because stress fractures are associated with low bone density and osteoporosis. “As internists, we know that evaluating people for their bone health is important.”

Plantar fasciitis is another common condition: One in 10 adults has had it, and it drives two million patients to their doctors each year, Dr. Ritter said.

It has classic symptoms. The discomfort is usually located over the plantar aspect of the heel, and is accompanied by pain with the first step out of bed in the morning, tenderness over the calcaneus, and a positive Windlass test (pain during passive dorsiflexion of the toes).

Abnormal biomechanics may play a role. Draw a line down the Achilles, and then connect that line to the calcaneal prominence, Dr. Ritter advised. If it's crooked, it's a sign. Also, there is the “too many toes” sign—examine a patient's leg from directly behind, and see if a few toes are visible because the foot points outward instead of straight ahead.

Anecdotally, there may be a seasonal component to plantar fasciitis as well. When people wear flip-flops or sandals in the summer, Dr. Ritter sees more cases of the disorder in her office.

X-rays are usually not needed. Even if bone spurs are found, they would not necessarily lead to a different diagnosis, and their presence is unlikely to change management, Dr. Ritter said.

Dr. Ritter expands on when to refer patients for imaging studies in the following video.

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Treatment involves ice and acetaminophen (instead of NSAIDs, since this is likely not an inflammatory condition), passive stretching, and massage (with a cold soda can, perhaps, Dr. Ritter suggested). There is no good evidence that supports custom orthotics over what might be available at the local pharmacy, and heel cups are probably not effective, she said. For nonresponsive cases, keep in mind that corticosteroid injections may have severe consequences, although botulinum toxin injections are one emerging modality.

More important is proper footwear that provides adequate cushioning. Change running shoes every 250 to 500 miles, and consider rotating shoes every other day, instead of repeatedly wearing the same pair, Dr. Ritter advises patients. She recommended examining patients' running shoes if they wear them to the appointment, and if they show uneven wear, patients should change them at 250 miles.

Midfoot pain

Tarsal tunnel syndrome is essentially the same as carpal tunnel syndrome, but in the feet, Dr. Ritter said. The tibial nerve shares space in a bony canal with multiple structures (blood vessels and tendons, among others) underneath the retinaculum. Symptoms involve paresthesias and pain of the plantar aspect of the foot, compared to plantar fasciitis, which is in the heel. Risk factors include overpronation, prior ankle injury or fracture, and space-occupying lesions. Upon examination, Tinel's test (lightly tapping over the nerve to elicit “pins and needles”) may be positive in patients with the syndrome.

Evaluation involves a nerve conduction study, but Dr. Ritter said, “Generally, I get X-rays first.” To treat the syndrome, address the underlying cause, consider orthotics especially if overpronation is present, and offer a referral for injection or a surgery similar to what is done for carpal tunnel syndrome.

Another common midfoot pain symptom stems from a metatarsal stress fracture. Such fractures are often seen with the “female athlete triad”: energy deficiency (with or without disordered eating), menstrual irregularities, and low bone density. Upon examination, there will be tenderness to palpation over the affected bones. X-rays may be negative initially. Treatment involves modifying activity and using a walking boot or still-soled shoe to allow pain-free ambulation. Consider referral for fractures in high-risk locations (i.e., Jones fracture), Dr. Ritter said.

“These are the runners [those with metatarsal stress fractures] who are not interested in decreasing their training, so you may have to give them some recommendations to come back before you give them the OK to advance their training,” Dr. Ritter said. “Twelve weeks would not be an unusual time to heal.”

Also consider the differential diagnoses of navicular stress fracture or a Lisfranc joint injury, Dr. Ritter said.

Of navicular stress fractures, Dr. Ritter said, “I've probably missed a few of these over the years.” Symptoms include a vague ache and insidious onset. They are seen in athletes and are also associated with the female athlete triad, usually in sports that involve jumping, sprinting, and rapidly changing direction, such as tennis.

Upon examination, there may be tenderness over the “N spot,” just lateral to the tibialis. The structure is on the top of the foot between the anterior tibial tendon and the extensor hallucis longus. A high index of suspicion is required. X-rays may be normal, requiring an MRI or bone scan for the diagnosis. Physicians can offer a walking boot and immediate referral. One study suggested that the average time to resolution of symptoms is nine months.

The tarso-metatarsal (Lisfranc) joint is complicated, but the most significant part is the medial base of the second metatarsal. Lisfranc joint injuries may be high-energy injuries that are often overlooked in the setting of concomitant, more serious injuries. “You may see them after they got out of the hospital and now they have pain in their foot,” Dr. Ritter noted. These injuries are distinguished by the “Fleck sign” on X-ray (avulsion of the medial base of the second metatarsal). A prompt referral is needed because this injury is associated with long-term disability, and patients may need surgery to correct it.

Similarly, Chopart's joint is a high-energy injury that is often overlooked in the setting of concomitant, more serious injuries. It is also an uncommon site of injury.

Forefoot pain

One common source of forefoot pain that Dr. Ritter discussed was metatarsalgia, a term that is used to refer to pain of the metatarsal heads.

Women develop this condition in an 8:1 ratio over men because of their footwear. Other risk factors include Morton's toe (a shortened first metatarsal in relation to the second metatarsal) and factors of aging, as the fat pads in the foot diminish and the transverse arch decreases.

Treatment is similar to that for other causes of forefoot pain: appropriate footwear (low heel and wide toe box) and support of the transverse arch with a metatarsal pad. The term for another forefoot condition, Morton's neuroma, is a misnomer, Dr. Ritter said. It represents thickening and irritation of a digital branch of the plantar nerve as it passes under the transverse metatarsal ligament. Patients may report “it feels like I have a pebble in my shoe.” Additional symptoms of the condition, which is seen in the second and third web spaces, include pain and burning, especially with high heels. Upon exam, symptoms may be reproduced with lateral-medial compression of metatarsal heads and/or palpation of web spaces. To diagnose, consider X-ray to evaluate for other bony abnormalities, and then an ultrasound or MRI if the diagnosis is in doubt, Dr. Ritter said.

Treatment involves off-loading the forefoot by using footwear with low heels and a wide toe box. Metatarsal pads may be helpful. Corticosteroid or alcohol injections have mixed evidence support, and physicians can also refer for surgical resection, Dr. Ritter advised.

Capsulitis typically involves pain on the “ball” of the foot, usually the second or third metatarsal head. It is associated with wearing high-heeled shoes or foot deformities such as a long second toe, bunions, or unstable foot arch. Pain may be worse with walking barefoot on hard surface. There will be tenderness to palpation.

X-ray can be used to rule out underlying deformities, and labs should be considered if there is a suspicion of rheumatoid or seronegative arthritis. Consider an MRI if diagnosis is in doubt or if ligament rupture is suspected, Dr. Ritter advised.

Treatment can include metatarsal pads or orthotics to offload the forefoot, NSAIDs and corticosteroid injections for pain control, and podiatry or orthopedic referral for consideration of metatarsal osteotomy or ligament repair if conservative measures fail, she said.

Bursitis may be associated with overuse, gout, rheumatoid arthritis, or infection. Signs include tenderness to palpation or tenderness with squeezing of the metatarsal heads. It can be further distinguished by a lack of radiation of the pain distally (vs. Morton's neuroma). An initial evaluation should include X-ray to rule out other pathology. MRI with contrast can identify fluid collections that are non-physiologic (>3 mm), Dr. Ritter said.

Similar to other conditions, it can be relieved by shoes with a wide toe box and low heels to reduce pressure, metatarsal pads, NSAIDs, and activity modification. If these fail, it may respond to injection, Dr. Ritter noted.

Freiburg's disease is an avascular necrosis of the metatarsal head. There may be insidious onset of pain, usually in the second or third metatarsal head. It is more common in women and adolescents, and high heels are again a factor, Dr. Ritter noted. There will be pain and tenderness over the involved metatarsal head. X-rays are often negative, but an MRI may show similar findings to a stress fracture and flattening of the metatarsal head.

While offloading the forefoot using metatarsal pads or orthotics may help symptoms in short term, referral is needed, Dr. Ritter said.