Musculoskeletal

Plantar fasciitis and Achilles tendinopathy

Clinical Overview and When to Suspect Plantar Fasciitis and Achilles Tendinopathy

— PF: degeneration at the medial calcaneal tuberosity where the plantar aponeurosis originates.

— AT: degeneration of the Achilles tendon, classified as insertional (within 2 cm of calcaneal insertion) or mid-portion/non-insertional (2–6 cm above insertion, the most common subtype).

Plantar fasciitis (PF) and Achilles tendinopathy (AT) are the two most common causes of activity-related heel pain in adult primary care, together accounting for the majority of "my heel hurts" outpatient visits.

Both are degenerative overuse enthesopathies, not primarily inflammatory — histology shows mucoid degeneration, collagen disorganization, and neovascularization rather than acute inflammation. The older suffix "-itis" persists by convention.

Suspect PF in a patient ≥40 with plantar medial heel pain worst with first steps in the morning or after prolonged sitting, easing with walking but worsening late in the day.

Suspect AT with posterior heel pain and morning stiffness along the tendon, often in a "weekend warrior" runner, a newly active middle-aged adult, or a patient recently started on a fluoroquinolone or glucocorticoid.

Shared risk factors: obesity (BMI >30), prolonged standing occupations, sudden increase in training load or hill running, inappropriate footwear, pes planus or cavus, tight gastrocnemius–soleus complex, and diabetes.

Drug-related risk for AT (Step 3 favorite): fluoroquinolones, systemic or local corticosteroids, statins, and aromatase inhibitors.

Board pearl: Heel pain with morning "first-step" pain pattern → plantar fasciitis; heel pain with palpable tendon thickening 2–6 cm above the calcaneus → Achilles tendinopathy.

Step 3 management: Both are clinical diagnoses — imaging is reserved for atypical features, failure of 6–12 weeks of conservative care, or suspicion of rupture, stress fracture, or systemic disease (e.g., spondyloarthritis).

Presentation Patterns and Key History

— 45-year-old runner, nurse, teacher, or warehouse worker with a BMI of 32 reports sharp medial heel pain with the first few steps out of bed and after standing up from a desk.

— Pain improves after a few minutes of walking ("start-up pain") but recurs after prolonged weight-bearing.

— Often unilateral but can be bilateral; bilateral or young patient should prompt thought about spondyloarthritis.

— Usually insidious onset over weeks; an acute "pop" suggests plantar fascia rupture, not fasciitis.

— 50-year-old recreational runner who recently increased mileage or hill work, or a sedentary adult who started a new sport, reports posterior heel/calf pain and stiffness, worse in the morning and at the start of activity, with a "warm-up phenomenon" — pain eases as the tendon warms, then returns after exercise.

— Insertional AT: pain right at the bone–tendon junction, often with a Haglund deformity (posterosuperior calcaneal prominence) and shoe-counter irritation.

— Mid-portion AT: pain and palpable thickening 2–6 cm above the insertion.

— Medication exposure: fluoroquinolones (within days–months), recent steroid injection, chronic glucocorticoids, statins.

— Sudden training change: new running program, terrain change, new shoes/orthotics.

— Systemic clues: low back pain with morning stiffness, uveitis, psoriasis, IBD, dactylitis → think enthesitis of spondyloarthritis.

— Trauma: sudden "kicked in the calf" sensation with audible pop → Achilles rupture, not tendinopathy.

— Night pain, fevers, weight loss → red flags for infection, malignancy, or inflammatory disease.

Plantar fasciitis classic stem:

Achilles tendinopathy classic stem:

Critical history elements (memorize for vignettes):

Key distinction: Tendinopathy pain improves with warm-up and worsens after activity; rupture pain is sudden, sharp, and disabling with loss of plantarflexion strength.

Board pearl: A young patient with bilateral heel pain + inflammatory back pain + HLA-B27 is testing spondyloarthritis-related enthesitis, not idiopathic PF.

Physical Exam Findings

— Point tenderness at the medial calcaneal tubercle (insertion of plantar fascia) is the single most reliable finding.

— Windlass test: passive dorsiflexion of the great toe with the ankle dorsiflexed reproduces plantar pain — fairly specific for PF.

— Tight Achilles/gastrocnemius with limited ankle dorsiflexion (<10°) is common and contributes to pathology.

— Look for pes planus or cavus, abnormal wear pattern on shoes, and obesity.

— Neurovascular exam should be normal; numbness, burning, or positive Tinel over the tarsal tunnel suggests tarsal tunnel syndrome or Baxter's nerve (first branch of lateral plantar) entrapment.

— Palpable tender thickening or nodularity of the tendon, classically 2–6 cm above the calcaneus (mid-portion) or at the insertion.

— Arc sign: a tender focal swelling that moves with the tendon during plantarflexion/dorsiflexion — supports tendinopathy over paratenonitis.

— Royal London Hospital test: tendon tenderness disappears with maximal dorsiflexion (tendon tightens) — supports tendinopathy.

— Reduced ankle dorsiflexion and weak heel-rise.

— Thompson (Simmonds) test: patient prone with feet hanging off the table; squeeze the calf — absent plantarflexion = positive = rupture.

— Palpable gap in the tendon, inability to perform a single-leg heel raise, and excessive resting dorsiflexion of the affected foot.

Plantar fasciitis exam:

Achilles tendinopathy exam:

Must-not-miss: Achilles rupture screening — always perform when AT is suspected, especially after acute worsening:

CCS pearl: In a patient with sudden posterior calf pain after a misstep, order Thompson test on physical exam first, then ultrasound — do not just prescribe NSAIDs and send home, as a missed rupture is a malpractice classic.

Board pearl: Reproducible pain with the windlass test in a patient with morning first-step heel pain essentially clinches PF — no imaging needed before starting conservative therapy.

Diagnostic Workup — Initial Evaluation

— Suspected acute Achilles rupture (positive Thompson, palpable gap, sudden onset).

— Trauma with concern for calcaneal stress fracture or contusion.

— Atypical features: night pain, constitutional symptoms, neurologic findings, mass, erythema, bilateral disease in young patient.

— Persistent symptoms despite 6–12 weeks of appropriate conservative therapy.

— Weight-bearing radiographs of the foot/ankle: rule out calcaneal stress fracture, tumor, retrocalcaneal exostosis, Haglund deformity, or insertional calcific tendinosis.

— A plantar calcaneal heel spur is seen in ~50% of PF patients but also in ~20% of asymptomatic adults — it is a marker, not a cause, and is not an indication for surgery.

— Insertional Achilles tendinopathy often shows calcification within the tendon insertion on lateral radiograph.

— PF: plantar fascia thickening >4 mm at the calcaneal origin (normal <4 mm), hypoechogenicity, loss of fibrillar pattern.

— AT: fusiform tendon thickening, hypoechoic foci, neovascularization on Doppler; can also detect partial tears and rupture.

Both PF and AT are clinical diagnoses. Routine labs and imaging are not indicated at initial presentation in a typical patient.

When to obtain imaging at first visit:

First-line imaging when needed:

Point-of-care ultrasound (POCUS) is increasingly first-line in primary care/sports clinics:

Labs: only if systemic disease is suspected — CBC, ESR/CRP, HLA-B27, uric acid, fasting glucose/HbA1c, RF/anti-CCP for inflammatory mimickers. Routine ordering is low-value care.

Key distinction: A heel spur on X-ray does not confirm plantar fasciitis and absence does not exclude it — diagnosis remains clinical.

Step 3 management: Begin conservative therapy on the day of the first visit in typical cases; defer imaging unless red flags are present or symptoms persist beyond 6–12 weeks.

Diagnostic Workup — Advanced or Confirmatory Studies

— PF: plantar fascia thickening, perifascial edema, marrow edema at the calcaneal insertion; excludes calcaneal stress fracture, plantar fibromatosis, infection, or tumor.

— AT: defines tendinopathy extent, identifies partial-thickness tears, retrocalcaneal bursitis, and Haglund-related impingement; mandatory if surgery is being planned.

— Operator-dependent but excellent for dynamic assessment, guided injections, and follow-up.

— Doppler neovascularization correlates with chronic tendinopathy and pain.

— Calcaneal stress fracture: positive calcaneal squeeze test, pain with hopping; MRI shows marrow edema. Common in runners, military recruits, postmenopausal women with low BMD.

— Tarsal tunnel syndrome: burning, paresthesias on plantar foot, positive Tinel behind the medial malleolus → electrodiagnostic studies (NCS/EMG) and MRI.

— Baxter's neuropathy (first branch of lateral plantar nerve): medial heel pain that mimics PF but with neuropathic quality; MRI may show abductor digiti minimi atrophy.

— Seronegative spondyloarthritis enthesitis: sacroiliac MRI, HLA-B27, CRP; consider in bilateral, young, or inflammatory-pattern disease.

— Sever disease (calcaneal apophysitis): adolescent athlete with posterior heel pain — clinical diagnosis, no advanced imaging needed.

MRI is the gold standard for refractory or atypical cases:

Ultrasound (in-office or radiology):

Specialized workup for mimickers:

Achilles rupture confirmation: Ultrasound first-line (fast, no radiation, dynamic); MRI if ultrasound equivocal or surgical planning.

Board pearl: A postmenopausal long-distance walker with worsening heel pain and a positive calcaneal squeeze has a calcaneal stress fracture until MRI proves otherwise — do not inject steroids.

Step 3 management: Reserve MRI for patients failing ≥3 months of structured conservative therapy, those with focal neurologic findings, or pre-procedural planning — routine MRI for typical PF/AT is low-value and not reimbursed in many value-based contracts.

Risk Stratification and First-Line Management Logic

— Weeks 0–6: education, relative rest/activity modification, footwear assessment, calf and plantar fascia stretching, ice, short-course NSAIDs if no contraindications.

— Weeks 6–12: formal physical therapy, structured eccentric loading program (AT) or high-load slow resistance training, prefabricated orthotics, night splints (PF).

— 3–6 months refractory: consider extracorporeal shock wave therapy (ESWT), custom orthotics, ultrasound-guided injection (selective).

— >6–12 months refractory: specialty referral for advanced procedures or surgery.

— Plantar fascia–specific stretching (Digiovanni protocol: dorsiflex toes, dorsiflex ankle, massage arch, hold 10s × 10 reps, 3×/day) — most evidence-based home intervention.

— Gastroc/soleus stretching, supportive shoes with arch support, OTC heel cups or arch supports, weight loss if BMI elevated.

— Night splints maintain dorsiflexion overnight, reducing morning first-step pain — particularly useful for symptoms >6 months.

— Eccentric heel-drop exercises (Alfredson protocol): 3 sets of 15, twice daily, for 12 weeks — cornerstone of mid-portion AT therapy, evidence-based.

— For insertional AT, modify to avoid dorsiflexion below neutral (do heel drops on flat ground, not off a step).

— Heel lifts (1–2 cm) reduce strain on the tendon, especially insertional disease.

— Relative rest, cross-training (cycling, swimming), gradual return-to-run program.

Both PF and AT respond to conservative care in 80–90% of patients within 6–12 months. Set expectations explicitly at the first visit — patients often want "a cure" and need to understand the timeline.

Tiered approach (stepped care):

PF-specific first-line bundle:

AT-specific first-line bundle:

Step 3 management: First visit should produce a written home exercise prescription and a 6-week follow-up appointment — vague "do some stretches" advice is a frequent wrong-answer distractor.

Board pearl: Eccentric loading for AT and plantar fascia–specific stretching for PF are the highest-yield, highest-evidence non-pharmacologic interventions.

Pharmacotherapy — First-Line Drug Options

— Short course (1–2 weeks) of ibuprofen 400–600 mg TID or naproxen 500 mg BID for pain control during the initial flare.

— Evidence for benefit is modest; avoid prolonged NSAID use in tendinopathy because chronic NSAIDs may impair tendon healing by suppressing collagen remodeling.

— Contraindications: CKD (eGFR <30), active peptic ulcer, anticoagulation, decompensated heart failure, late pregnancy.

— In older adults, combine with PPI if GI risk factors, monitor BP and renal function.

— Diclofenac gel 1% (Voltaren) or solution applied to the affected area QID — useful in older adults and those with systemic NSAID contraindications. Effective for superficial Achilles tendon pain, less so for deeper PF.

— Some evidence for mid-portion AT — promotes collagen synthesis via nitric oxide.

— Side effects: headache, contact dermatitis. Modest effect, niche use.

— Fluoroquinolones: discontinue immediately if AT develops; warn patient about rupture risk (highest in first month, persists up to 6 months).

— Statins, aromatase inhibitors: review risk–benefit; usually continue but counsel.

Pharmacotherapy is adjunctive, not curative — it controls symptoms so patients can perform rehab.

NSAIDs (oral):

Topical NSAIDs:

Acetaminophen up to 3 g/day: weaker analgesic effect but safer in renal disease, anticoagulation, and elderly.

Topical nitroglycerin patches (0.1–0.2 mg/hr) applied over the tendon:

Avoid systemic corticosteroids for either condition — no benefit, plus tendon-weakening risk.

Avoid opioids entirely — chronic musculoskeletal overuse pathology, addiction risk, no evidence of benefit. A common Step 3 distractor in opioid stewardship questions.

Drugs to STOP if possible:

Board pearl: NSAIDs for tendinopathy = short courses only. Long-term NSAID use is a wrong-answer choice on Step 3 because it impairs the very healing process you're trying to support.

Step 3 management: Document NSAID counseling on GI/renal/CV risks and set a stop date in the chart.

Procedures and Advanced Interventions

— FDA-approved for chronic PF and AT refractory to ≥3–6 months of conservative therapy.

— Outpatient, 3–5 sessions, minimal downtime; promotes neovascularization and collagen remodeling.

— Best evidence-supported procedural option for both conditions; should precede injections or surgery.

— PF: ultrasound-guided injection at the medial calcaneal origin provides short-term (4–6 week) pain relief; risk of plantar fascia rupture (~10%) and fat pad atrophy — limit to ≤1–2 injections, avoid repeat dosing.

— AT: avoid intratendinous corticosteroid injection — high risk of tendon rupture. Peritendinous (paratenon) injection under ultrasound for retrocalcaneal bursitis only, by an experienced clinician.

— Mixed evidence; modest benefit for mid-portion AT; insurance rarely covers. Counsel on cost and uncertain efficacy.

— PF: partial plantar fasciotomy (open or endoscopic); risk of arch collapse, lateral foot pain; gastrocnemius recession (Strayer procedure) for patients with isolated gastroc tightness.

— AT:

– Mid-portion: tendon debridement, paratenon stripping, gastrocnemius recession.

– Insertional: debridement of degenerative tendon, Haglund's resection, FHL tendon transfer if >50% of tendon involved.

— Functional rehab with early weight-bearing in a boot or surgical repair — re-rupture rates similar with modern functional protocols; surgery favored in young athletes.

Extracorporeal shock wave therapy (ESWT):

Corticosteroid injection:

Platelet-rich plasma (PRP):

Other injectables: botulinum toxin (PF, off-label), high-volume saline injections, prolotherapy — limited evidence, specialist-driven.

Percutaneous tenotomy / Tenex (ultrasound-guided percutaneous needle fenestration or ultrasonic debridement): emerging option for chronic refractory tendinopathy.

Surgery — last resort after ≥6–12 months of failed conservative care:

Achilles rupture management (must distinguish from tendinopathy):

CCS pearl: Order ultrasound-guided injection rather than landmark-based — improves accuracy and reduces inadvertent intratendinous deposition.

Board pearl: Steroid injection into an Achilles tendon = wrong answer.

Special Populations — Elderly and Renal/Hepatic Impairment

— Higher prevalence of both PF and AT due to fat pad atrophy, decreased tendon elasticity, sarcopenia, and polypharmacy.

— Heel pad atrophy mimics PF with diffuse central heel pain (not localized to medial tubercle) and is worse on hard surfaces — treat with cushioned heel cups, not steroid injection.

— Avoid systemic NSAIDs when possible: increased risk of GI bleed, AKI, hypertension exacerbation, and heart failure decompensation. Prefer topical diclofenac and acetaminophen.

— Falls risk: be cautious with night splints (can cause stumbling) and walking boots (limb-length discrepancy → contralateral hip/knee pain, gait instability) — provide a contralateral EvenUp shoe lift when boot is used.

— Screen for and treat vitamin D deficiency and osteoporosis if calcaneal stress fracture is found.

— NSAIDs contraindicated when eGFR <30, use with extreme caution at eGFR 30–60 and only short-term with monitoring.

— Acetaminophen and topical diclofenac are safer.

— Be aware that CKD patients on fluoroquinolones have markedly increased tendon rupture risk (dose accumulates).

— Limit acetaminophen to ≤2 g/day in significant cirrhosis or active alcohol use.

— NSAIDs increase risk of variceal bleed and hepatorenal syndrome in cirrhosis — avoid.

— Higher rates of tendinopathy due to collagen glycation; tendons are stiffer and more rupture-prone.

— Screen for and treat peripheral neuropathy, which can mask early symptoms and increase ulcer risk with orthotics/splints.

— Counsel that glycemic control supports healing.

Elderly patients (≥65):

Chronic kidney disease (CKD):

Hepatic impairment:

Diabetic patients:

Board pearl: Diffuse central heel pain in a thin elderly patient on a hard floor → heel pad atrophy, not PF; treat with cushioning.

Step 3 management: In older adults, default to topical NSAID + acetaminophen + PT rather than systemic NSAIDs, and reassess at 4–6 weeks.

Special Populations — Pregnancy, Pediatrics, and Athletes

— PF prevalence rises in the second and third trimesters due to weight gain, relaxin-mediated ligamentous laxity, fluid retention, and arch flattening.

— Treatment: supportive shoes, OTC arch supports, ice, stretching, weight management.

— NSAIDs: avoid in first trimester (miscarriage risk) and contraindicated after 20 weeks (oligohydramnios, premature closure of ductus arteriosus per 2020 FDA warning); acetaminophen is preferred.

— Avoid corticosteroid injections in routine cases; symptoms usually resolve postpartum.

— Sever disease (calcaneal apophysitis): most common cause of pediatric heel pain, ages 8–14, active in running/jumping sports. Tender on medial-lateral squeeze of the calcaneus, not at the plantar fascia. Self-limited; treat with relative rest, heel cups, calf stretching, return to play as tolerated.

— Osgood-Schlatter analog of the heel mentally — apophyseal traction injury.

— Consider osteomyelitis, juvenile idiopathic arthritis (enthesitis-related), tarsal coalition, or bone tumor if night pain, fevers, or atypical features.

— Insertional AT is common in middle-aged recreational runners; mid-portion AT dominates in elite runners.

— Address training errors: ≥10% weekly mileage increase, hill work, hard surfaces, worn shoes (replace every 300–500 miles).

— Return-to-run criteria: pain-free single-leg heel raise × 25 reps, full ankle dorsiflexion, completion of progressive walk-to-run program.

— Counsel athletes that resolving pain takes 3–6 months; rushing back causes recurrence.

Pregnancy:

Pediatrics — heel pain in children is NOT plantar fasciitis or AT until proven otherwise:

Athletes and tactical workers (military, dancers):

Key distinction: A 12-year-old soccer player with posterior heel pain has Sever disease, not Achilles tendinopathy — squeeze test localizes to the apophysis, and imaging is usually unnecessary.

Board pearl: NSAIDs after 20 weeks gestation → fetal renal injury and oligohydramnios; switch to acetaminophen and non-pharmacologic measures.

Complications and Adverse Outcomes

— Plantar fascia rupture: spontaneous (often after steroid injection) or traumatic; acute sharp pain with a pop, ecchymosis along the arch, palpable defect. Treat with immobilization in a walking boot for 2–4 weeks; surgery rarely needed.

— Achilles tendon rupture: classic in a middle-aged "weekend warrior" with prior tendinopathy or fluoroquinolone exposure. Sudden "kick in the calf" sensation, positive Thompson test. Management: functional bracing vs surgical repair — discuss risks/benefits and shared decision making.

— Chronic pain syndromes: persistent pain >12 months with central sensitization; consider multidisciplinary pain management.

— Gait alteration → secondary injuries: knee, hip, contralateral foot pain from antalgic gait or unilateral walking boot use.

— Corticosteroid injection: plantar fascia rupture (~10% of injected PF patients), heel fat pad atrophy (permanent, painful), skin depigmentation, infection. Intratendinous Achilles steroid → rupture.

— Surgical complications: wound infection (especially diabetics, smokers), nerve injury (sural nerve in Achilles surgery, Baxter's nerve in plantar fasciotomy), prolonged rehab (3–6 months back to sport), arch collapse after fasciotomy.

— NSAID toxicity: GI bleed, AKI, hypertension worsening.

— Fluoroquinolone tendinopathy: bilateral Achilles involvement in 50%, rupture in ~1%; risk persists up to 6 months post-exposure and is markedly increased with concurrent corticosteroid use and age >60.

— Undiagnosed calcaneal stress fracture progressing to displaced fracture.

— Missed Achilles rupture → chronic dysfunction, equinus contracture, weak push-off.

— Missed spondyloarthritis → progression of axial disease.

Disease-related complications:

Treatment-related complications:

Missed-diagnosis complications:

Board pearl: A patient on a fluoroquinolone who develops Achilles pain → stop the antibiotic, switch to an alternative class, immobilize, and counsel about rupture risk for 6 months.

Step 3 management: Document a clear rupture-warning conversation when prescribing fluoroquinolones in patients >60 or on steroids.

When to Escalate Care — Referrals and Inpatient Triage

— Failure of ≥3–6 months of structured conservative therapy.

— Suspected Achilles rupture (urgent, within days).

— Suspected plantar fascia rupture or chronic partial tear.

— Recurrent disease after prior injection or surgery.

— Insertional AT with significant Haglund deformity or intratendinous calcification.

— Atypical or multifocal enthesopathy → rheumatology for spondyloarthritis workup.

— Acute Achilles rupture: needs imaging, immobilization in plantarflexion (resting equinus splint or boot with heel wedges), and orthopedic consultation within 1–2 weeks for definitive management.

— Suspected septic arthritis or osteomyelitis: erythema, warmth, fever, systemic illness → ED for blood cultures, joint aspiration, MRI, IV antibiotics.

— DVT mimicking calf-region AT: unilateral calf swelling, recent travel, malignancy, OCP — order D-dimer or duplex ultrasound before assuming tendinopathy.

PF and AT are almost entirely outpatient conditions — inpatient management is rare and usually reflects a missed alternative diagnosis (osteomyelitis, septic bursitis, DVT, complete rupture requiring urgent surgery).

Refer to orthopedics/podiatry/sports medicine:

Refer to physical therapy early — ideally at the first or second visit — for supervised eccentric loading (AT) and plantar fascia–specific stretching (PF) progression.

Refer to pain management for chronic refractory pain with central sensitization features.

Urgent same-day evaluation indications:

CCS pearl: In a CCS case of "posterior calf pain in a 55-year-old," the correct early orders include Thompson test on exam, lower extremity ultrasound (to rule out both DVT and rupture), and orthopedic consult if rupture is confirmed — not just NSAIDs and follow-up.

Board pearl: Bilateral heel enthesitis + inflammatory back pain + uveitis → refer to rheumatology, check HLA-B27 and sacroiliac imaging; this is spondyloarthritis, not idiopathic PF.

Key Differentials — Other Musculoskeletal Heel Causes

— Postmenopausal women, military recruits, long-distance runners with rapid mileage increase.

— Positive calcaneal squeeze test (medial-lateral compression of the calcaneus reproduces pain).

— Diffuse heel pain, worse with hopping; MRI shows marrow edema.

— Treat with boot immobilization, non-weight-bearing or protected weight-bearing, vitamin D and calcium, evaluate for female athlete triad/RED-S or osteoporosis.

— Elderly, diffuse central heel pain, worse on hard surfaces, not focally tender at medial tubercle.

— Treat with cushioned heel cups, avoid steroid injection (would worsen atrophy).

— Pain anterior to the Achilles tendon insertion, swelling in the "soft spot" between tendon and calcaneus.

— Often coexists with insertional AT and Haglund deformity.

— Bony posterosuperior calcaneal prominence irritated by shoe counter; causes posterior heel pain, often with insertional AT.

— Burning, tingling, numbness on plantar foot; positive Tinel behind the medial malleolus.

— Diagnose with NCS/EMG and MRI.

— Medial heel pain mimicking PF but with neuropathic features and lateral radiation; MRI may show abductor digiti minimi denervation.

— Palpable firm nodule along the plantar fascia, not at the calcaneal origin; associated with Dupuytren contracture.

— Medial ankle/arch pain, progressive flatfoot, "too many toes" sign from behind, weak single-leg heel raise.

Calcaneal stress fracture:

Heel fat pad atrophy/syndrome:

Retrocalcaneal bursitis:

Haglund deformity ("pump bump"):

Tarsal tunnel syndrome:

Baxter's neuropathy (first branch of lateral plantar nerve):

Plantar fibromatosis (Ledderhose disease):

Posterior tibial tendinopathy:

Achilles paratenonitis (true inflammation of paratenon, often acute, with crepitus) vs tendinosis (chronic degeneration without inflammation) — different timelines and management.

Key distinction: Point tenderness location is the most useful single discriminator — medial calcaneal tubercle (PF) vs central heel (fat pad) vs 2–6 cm above insertion (mid-portion AT) vs apophysis (Sever) vs squeeze-positive bone (stress fracture).

Key Differentials — Systemic and Other-Category Causes

— Conditions: ankylosing spondylitis, psoriatic arthritis, reactive arthritis, IBD-associated arthritis, enthesitis-related juvenile idiopathic arthritis.

— Heel enthesitis at the plantar fascia or Achilles insertion is a hallmark, especially when bilateral, young (<40), or accompanied by inflammatory back pain (morning stiffness >30 min, improves with activity).

— Workup: HLA-B27, CRP/ESR, sacroiliac MRI, dermatologic and GI history, uveitis history.

— Treatment: NSAIDs first-line, then DMARDs/biologics (TNF inhibitors) — refer to rheumatology.

Seronegative spondyloarthritis (enthesitis-predominant disease):

Gout/CPPD: acute monoarticular inflammation can affect the Achilles insertion or peritendinous tissues; sudden onset, erythema, exquisite tenderness — aspirate if possible. Tophaceous deposits can mimic chronic tendinopathy.

Rheumatoid arthritis: rarely primary cause of heel pain, but tendon nodules and bursitis can occur.

Diabetic neuropathy and Charcot foot: painless or atypical heel pain in long-standing diabetes — assess sensation with monofilament, evaluate for deformity, redness, warmth.

Peripheral arterial disease: claudication mimics activity-related calf pain; check pulses, ABI if absent. Ischemic rest pain affects forefoot, not heel typically.

Deep vein thrombosis: calf pain and swelling — always consider in unilateral lower-extremity pain, especially with risk factors (malignancy, immobility, OCP, recent surgery, travel).

Sciatica / S1 radiculopathy: posterior heel pain radiating from low back, with paresthesias along the lateral foot and weak plantarflexion. Straight-leg raise positive; check reflexes (absent ankle jerk).

Infection: osteomyelitis (especially diabetic foot), septic bursitis, cellulitis — fever, warmth, erythema, leukocytosis.

Malignancy: primary bone tumors (rare), metastases — night pain, weight loss, prior cancer history.

Board pearl: A 28-year-old man with bilateral heel pain, dactylitis, and a psoriatic plaque on the elbow has psoriatic enthesitis, not idiopathic PF — order rheumatology referral, not just stretching.

Secondary Prevention and Long-Term Plan

— Weight reduction: BMI >27 strongly increases PF risk; even 5–10% loss improves symptoms and prevents recurrence.

— Footwear: cushioned, supportive shoes with a slight heel rise; replace running shoes every 300–500 miles.

— Calf flexibility: lifelong daily calf and plantar fascia stretching, especially for occupations involving prolonged standing.

— Gradual training progression: 10% rule — increase running mileage or activity intensity by no more than 10% per week.

— Cross-training: cycling, swimming, elliptical to reduce repetitive impact load.

— Start with OTC prefabricated arch supports/heel cups — equivalent outcomes to custom orthotics in most trials.

— Custom orthotics for high arches, severe pes planus, leg-length discrepancy, or refractory cases.

— Heel lifts (bilateral) for chronic Achilles tendinopathy to offload the tendon during gradual return to activity.

— Avoid unnecessary fluoroquinolones, especially in older adults and athletes — substitute alternative antibiotic classes when possible.

— Discuss tendinopathy risk when initiating statins, aromatase inhibitors, or systemic corticosteroids.

— PF: pain-free morning first step for ≥1 week.

— AT: pain-free single-leg heel raise × 25, completion of structured walk-to-run progression.

Modifiable risk factors — address at every visit:

Orthotic strategy:

Medication review:

Bone health: if calcaneal stress fracture was the diagnosis, evaluate for osteoporosis (DEXA), correct vitamin D and calcium, consider hormonal evaluation in young female athletes (RED-S/female athlete triad).

Comorbidity optimization: glycemic control in diabetes, smoking cessation (impairs tendon healing), inflammatory disease control if spondyloarthritis.

Return-to-activity benchmarks:

Board pearl: Weight loss, footwear assessment, and an eccentric/stretching home program are the three most durable long-term preventive interventions.

Step 3 management: At discharge or after symptom resolution, schedule a 3-month phone or in-person check to reinforce maintenance stretching and prevent recurrence.

Follow-Up, Monitoring, and Counseling

— Initial visit: clinical diagnosis, education, written exercise prescription, NSAID short course if appropriate, footwear/orthotic advice, follow-up in 6 weeks.

— 6-week visit: reassess pain (0–10 scale), function (FAAM or simple "stairs, walking distance, work tolerance"), adherence to home exercises. If improving, continue; if no progress, escalate to formal PT, night splint (PF), or imaging.

— 3-month visit: if still symptomatic, consider ESWT referral, ultrasound-guided injection (PF, not AT), or orthopedics/podiatry consultation.

— 6-month visit: surgical consultation for true refractory disease.

— Symptom diary or pain scores at each visit.

— Exercise adherence (ask explicitly: "How many days per week did you do the heel drops?").

— Functional measures: ability to perform single-leg heel raise (AT), morning first-step pain (PF), return to walking/running distance.

— Weight and BP trends if NSAIDs prescribed; renal function in CKD patients on chronic NSAIDs.

— Recovery is slow — 6 to 12 months is typical; setting this expectation prevents frustration and unnecessary doctor-shopping or premature procedures.

— Pain during eccentric exercises is acceptable (up to 4–5/10) and does not indicate harm — many patients stop the most effective therapy because they think pain = damage.

— Avoid abrupt return to high-impact activity; structured progression is essential.

— Warning signs that warrant urgent return: sudden pop or sharp pain, inability to push off, calf swelling, fever, night pain.

Follow-up cadence (typical primary care plan):

Monitoring parameters:

Counseling points to deliver explicitly:

Patient education tools: AAFP and AAOS handouts, video demonstrations of eccentric heel drops and plantar fascia–specific stretching, app-based exercise reminders.

CCS pearl: Schedule the 6-week follow-up at the initial visit — both as a quality measure and to capture early treatment failures before they become chronic.

Board pearl: Non-adherence to the home exercise program is the single most common reason for "treatment failure" — always ask before escalating care.

Ethical, Legal, and Patient Safety Considerations

— Disclose plantar fascia rupture risk (~10%) and fat pad atrophy before any heel injection.

— Document discussion explicitly; this is a high-litigation injection because complications are permanent and patients often expected a "cure."

— Use ultrasound guidance to reduce risk and as a defensible standard of care.

— Intratendinous corticosteroid injection into the Achilles is generally considered below the standard of care due to high rupture risk. If considered for peritendinous bursitis, must be ultrasound-guided, by experienced clinicians, with thorough informed consent.

— Whenever prescribing fluoroquinolones, especially in patients >60, on steroids, or with prior tendinopathy, counsel on tendon rupture risk and document.

— Avoid fluoroquinolones for uncomplicated indications (sinusitis, uncomplicated UTI, bronchitis) where alternatives exist — FDA explicitly recommends against use for these indications.

— A missed counseling step → tendon rupture → litigation exposure.

— When transferring a patient on a fluoroquinolone who develops new heel/calf pain, explicitly communicate to the next provider to stop the antibiotic, immobilize, and consider rupture workup. Hand-off failures are a common Step 3 patient-safety theme.

— When discharging a patient in a walking boot, provide a contralateral shoe lift to prevent gait-related falls and contralateral injuries.

— Opioids should not be prescribed for PF or AT — they offer no functional benefit, expose patients to addiction, and are flagged on quality metrics.

— Document objective findings and functional limits for work accommodations (e.g., "no prolonged standing >2 hours") rather than blanket "off work" notes.

— Address occupational risk: standing-heavy jobs may need anti-fatigue mats, supportive footwear allowances, or temporary duty modification.

Informed consent for corticosteroid injection (PF):

Achilles steroid injection — standard of care says NO:

Fluoroquinolone counseling — FDA black box:

Transition-of-care safety:

Opioid stewardship:

Disability and work issues:

Health equity consideration: custom orthotics and PT access are often insurance-limited — start with OTC options and home exercise programs to ensure equitable first-line care.

Board pearl: "Counsel about tendon rupture" is the right answer whenever a fluoroquinolone is prescribed, especially in older adults.

High-Yield Associations and Rapid-Fire Clinical Facts

Plantar fasciitis = first-step morning pain at the medial calcaneal tubercle; positive windlass test.

Achilles tendinopathy = posterior heel pain with warm-up phenomenon; tender thickening 2–6 cm above insertion (mid-portion) or at insertion with Haglund deformity (insertional).

Heel spur: present in ~50% of PF and ~20% of asymptomatic adults — not causative, not a surgical indication.

Eccentric heel-drop exercises (Alfredson) = cornerstone of mid-portion AT therapy.

Plantar fascia–specific stretching (Digiovanni) = most evidence-based PF home intervention.

Night splints = helpful for PF symptoms >6 months.

Heel lifts = useful for insertional AT.

ESWT = best procedural option after ≥3–6 months of failed conservative therapy.

Steroid injection into Achilles = wrong answer; risk of rupture.

Fluoroquinolones + corticosteroids + age >60 = highest tendon rupture risk; bilateral Achilles involvement in 50%.

Calcaneal squeeze test positive → calcaneal stress fracture.

Thompson test positive (no plantarflexion on calf squeeze) → Achilles rupture.

Bilateral heel pain + young patient + inflammatory back pain → think spondyloarthritis (HLA-B27).

Sever disease: pediatric heel pain (8–14 yo), squeeze-positive calcaneal apophysis — self-limited.

Heel pad atrophy: elderly, central diffuse heel pain — treat with cushioning, not steroids.

Plantar fibromatosis (Ledderhose): plantar nodule, associated with Dupuytren contracture.

Baxter's neuropathy: mimics PF but neuropathic; MRI shows abductor digiti minimi atrophy.

Tarsal tunnel: positive Tinel posterior to medial malleolus; confirm with NCS/EMG.

Single-leg heel raise × 25 pain-free = return-to-run criterion for AT.

10% rule = increase training load by ≤10% per week to prevent overuse injuries.

Recovery timeline: 80–90% resolve with conservative care in 6–12 months.

NSAIDs after 20 weeks gestation = contraindicated (oligohydramnios, ductus closure).

Diabetic patients: stiffer, more rupture-prone tendons due to collagen glycation.

Board pearl: When the stem mentions "first step out of bed," answer plantar fasciitis; when it mentions "stiffness that warms up," answer Achilles tendinopathy.

Board Question Stem Patterns

Pattern 1 — Classic PF: 45-year-old obese teacher with sharp medial heel pain on first morning steps that eases with walking. Exam: tender medial calcaneal tubercle, positive windlass. Next step? → Plantar fascia–specific stretching, supportive footwear, and reassurance; not MRI or steroid injection.

Pattern 2 — Classic mid-portion AT: 50-year-old runner who increased mileage 30% in two weeks now has posterior heel pain with morning stiffness, palpable thickening 4 cm above insertion. Next step? → Eccentric heel-drop program (Alfredson) for 12 weeks, relative rest, NSAIDs short course.

Pattern 3 — Fluoroquinolone tendinopathy: 70-year-old on prednisone given ciprofloxacin for "UTI" now has bilateral Achilles pain. Next step? → Stop ciprofloxacin, switch antibiotic, immobilize, counsel on rupture risk for 6 months.

Pattern 4 — Achilles rupture: 45-year-old recreational basketball player feels a "pop" in the calf, falls, cannot push off. Exam: palpable gap, positive Thompson. Next step? → Immobilize in plantarflexion, orthopedic referral, ultrasound for confirmation.

Pattern 5 — Calcaneal stress fracture: Postmenopausal woman walking long distances, diffuse heel pain, positive squeeze test. Radiographs normal. Next step? → MRI, boot immobilization, DEXA, vitamin D/calcium.

Pattern 6 — Spondyloarthritis enthesitis: 28-year-old man, bilateral heel pain, inflammatory back pain, prior uveitis. Next step? → HLA-B27, sacroiliac MRI, rheumatology referral.

Pattern 7 — Sever disease: 11-year-old soccer player with posterior heel pain, tender on calcaneal squeeze. Next step? → Relative rest, heel cups, calf stretching; no imaging required.

Pattern 8 — Wrong-answer distractor in AT: "Intratendinous corticosteroid injection" → never select this for the Achilles tendon.

Pattern 9 — Refractory PF after 6 months: Failed PT, stretching, orthotics, NSAIDs. Next step? → ESWT or ultrasound-guided corticosteroid injection (with consent re: rupture); not immediate surgery.

Pattern 10 — Heel pad atrophy mimic: Thin 78-year-old with central heel pain on hard floors. Next step? → Cushioned heel cups, not steroid injection.

Board pearl: Step 3 favors the conservative, evidence-based, time-bounded answer — eccentric loading, stretching, footwear, and 6-week follow-up beat MRI/injection/surgery in the typical stem.

One-Line Recap

Plantar fasciitis and Achilles tendinopathy are clinical diagnoses of degenerative overuse enthesopathies, managed primarily with patient education, targeted loading exercises (plantar fascia–specific stretching for PF, eccentric heel drops for AT), supportive footwear, and time — with imaging, injections, and surgery reserved for refractory or atypical cases.

Diagnosis is clinical: medial calcaneal tubercle tenderness with positive windlass (PF) vs posterior tendon thickening with warm-up phenomenon (AT); reserve imaging for red flags, suspected rupture, or failure of ≥3 months of conservative care.

First-line therapy is non-pharmacologic: plantar fascia–specific stretching and calf stretching (PF), eccentric heel-drop program (AT), supportive footwear/orthotics, weight loss, activity modification, and a 6-week structured follow-up.

Avoid the classic wrong answers: intratendinous Achilles steroid injection, long-term NSAIDs, opioids, immediate MRI for typical presentations, and surgery before 6–12 months of structured conservative care.

Always think rupture and red flags: Thompson test for suspected Achilles rupture, calcaneal squeeze for stress fracture, bilateral young heel pain for spondyloarthritis, and fluoroquinolone exposure for drug-induced tendinopathy — and counsel/document rupture risk whenever prescribing fluoroquinolones in older patients or those on corticosteroids.

Board pearl: The Step 3 answer pattern is "educate, stretch, modify, reassess in 6 weeks" — conservative, evidence-based, time-bounded management nearly always beats imaging or procedures for the typical heel-pain stem.