e5-08: Plantar Fasciitis

Plantar fasciitis is the most prevalent condition treated by podiatrists and is the most common cause of heel pain. Each year, an estimated 2 million Americans are affected, resulting in more than 1 million clinician visits. The estimated annual cost of treatment for plantar fasciitis is between $192 and $376 million.

The plantar fascia is a thick and fibrous aponeurosis that helps support the medial longitudinal arch of the foot through the windlass effect. It originates at the medial calcaneal tubercle and forms three bands: a thick central band and thinner medial and lateral bands. The plantar fascia divides distally into digital bands that insert onto the base of the proximal phalanx of each digit and metatarsal heads. Fibers from the plantar fascia also blend into the deep transverse metatarsal ligament and the flexor sheath.

Plantar fasciitis is believed to be caused by repetitive microtrauma and biomechanical overuse. Risks factors include pes planus as well as pes cavus foot types, obesity, limb length discrepancy, Achilles tendon tightness, and occupations that require prolonged standing or walking.

A. Symptoms and Signs

The chief complaint is typically sharp and stabbing heel pain that is most severe in the morning or standing after rest. The pain usually improves with ambulation but may worsen after activity or at the end of the day. On physical examination, there is localized tenderness upon palpation of the medial calcaneal tubercle. Passive dorsiflexion of the hallux may cause pain or discomfort in the plantar fascia. Evaluation of the ankle joint may reveal decreased dorsiflexion, indicating a tight Achilles tendon.

B. Imaging

Imaging is rarely needed since the diagnosis of plantar fasciitis is usually clinical. Imaging should be obtained if the diagnosis is uncertain or the patient has not responded to treatment. Weight-bearing anteroposterior, medial oblique, and lateral views of the foot can determine biomechanical etiologies of plantar fasciitis. An infracalcaneal heel spur seen on the radiograph may be associated with symptoms of plantar fasciitis and can indicate that the condition has occurred chronically. However, a heel spur does not necessarily correlate with symptoms and is found in asymptomatic individuals (15–25% of the general population); many patients with plantar fasciitis do not have heel spurs.

Changes in the consistency and thickness of the plantar fascia have been noted both on MRI and ultrasonography in patients with plantar fasciitis; however, these diagnostic tests should be reserved for confirmation of plantar fascia rupture.

A neurologic etiology of heel pain can be assessed by examining for paresthesias, Tinel sign, or motor weakness. Examination for traumatic causes of heel pain is performed by squeezing the calcaneus and inspection of the heel for trauma and wounds.

A. Conservative

Initial treatment of plantar fasciitis consists of stretching the Achilles and plantar fascia, padding and strapping of the arch, supportive shoe gear, rest and avoidance of high-impact activities, orthotics, oral nonsteroidal anti-inflammatory drugs, night splints, and corticosteroid injections. Instructions to stretch the Achilles and plantar fascia is as follows: stand an arm's length from a wall, place your right foot behind your left, slowly and gently bend your left leg forward, keep your right knee straight and your right heel on the ground, hold the stretch for 15 to 30 seconds and release, reverse the position of your legs, and repeat. Patients typically respond to treatment within 6 weeks; if the patient experiences improvement in symptoms, the treatment should be continued until resolution. Extracorporeal shock wave therapy, iontophoresis, botulinum toxin injections, and platelet-rich plasma (PRP) injections have shown promising results but have not been supported with good-quality evidence. Limited evidence supports the conclusion that any of the newly mentioned modalities are superior to steroid injections or other conservative methods of treatment.

B. Surgical

Plantar fasciotomy done through either open or endoscopic technique may be effective for plantar fasciitis that does not respond to conservative treatment after 1 year.

• If the patient has not responded to conservative treatment within 6 weeks.

• If the diagnosis is uncertain or another source of heel pain is suspected.