Insertional tendinopathies

Insertional tendinopathies are common disorders caused by repetitive strain on tendons at their point of origin or insertion on a bone. Insertional tendinopathies are most common in athletes and people who regularly perform repetitive movements (e.g., typing, assembly-line work). The Achilles, patellar, forearm, and rotator cuff tendons are most commonly affected. Insertional tendinopathies typically manifest with insidious onset of focal pain and tenderness and are associated with an increase in activity. Diagnosis is usually clinical. In cases of diagnostic uncertainty, x-ray is used to rule out bone pathology and is followed by either ultrasound or MRI. Conservative management leads to complete remission in most patients. For refractory symptoms, treatment options include glucocorticoid injections, extracorporeal shock wave therapy, and surgery.

This article covers lateral epicondylitis, medial epicondylitis, iliotibial band syndrome, patellar tendinopathy, and Achilles tendinopathy. Rotator cuff tendinopathy, biceps tendinopathy, and greater trochanteric pain syndrome are covered in other articles.

• Overuse or overload injury (repetitive, excessive strain), degeneration
• Skeletal abnormalities with strain on tendons (e.g., genu varum)
• Acute trauma (laceration, rupture)
• Risk factors
  • Occupation: athletes, workers who do manual labor or repetitive movements involving the same muscle
  • Errors in physical training (e.g., sudden increase in exercise intensity, inadequate rest, hard/uneven training grounds, ill-fitting/inappropriate footwear)
  • Obesity
  • Previous tendon injuries
  • Recent use of fluoroquinolones

• Contraction of a skeletal muscle → transmission of force through the tendon to the bone at the point of tendon insertion
• Repetitive strain → microtrauma of the tendon → improper healing → disorientation of the tendon's collagen fibers → tendinopathy
• Hypovascularity → predisposition to hypoxic tendon degeneration

Unlike in cases of tendinitis or tenosynovitis, inflammation plays a negligible role in the development of tendinopathy.

Lateral epicondylitis is an overuse injury of the elbow, especially the finger extensor tendons that originate in the lateral humeral epicondyle. Despite the term “epicondylitis,” there is no inflammation of the epicondyle; instead there is degeneration of the forearm tendons. ^[1][2]

Epidemiology ^[2]

• Most common in adults aged 40–60 years of age
• ♂ = ♀

Etiology

• Most commonly due to: ^[1][3]
  • Repeated or excessive pronation/supination and extension of the wrist (e.g., backhand shots in racket sports)
  • Occupational activities (such as computer use)
• Can also be idiopathic

An EXTended game of tennis will ruin the Lawn: repeated EXTension of the elbow (e.g., in tennis) causes lateral epicondylitis.

Clinical features ^[1]

• Lateral elbow pain ^[2]
• Pain on extension of the wrist
• Reduced grip strength
• On examination, there is pain and tenderness over the lateral epicondyle and along extensor muscles. ^[2]

Diagnosis ^[2]

• Clinical diagnosis based on history and provocation testing
• Provocation testing
  • Cozen test (tennis elbow test) ; ^[4][5]
    • The examiner holds the patient's hand with the thumb placed over the lateral epicondyle.
    • The patient makes a fist, pronates the forearm, deviates radially, and extends the fist against the examiner's resistance.
    • Test is positive if pain is elicited over the lateral epicondyle.
  • Alternatives: Mill test or Maudsley test
• For diagnostic uncertainty: Consider imaging. ^[6]
  • Initial test: x-ray to exclude differential diagnoses
  • Advanced imaging
    • Modalities: ultrasound or MRI without contrast of the elbow ^[1]
    • Findings: tendon thickening,irregular orientation of fibers

Differential diagnoses of lateral epicondylitis^[2]

• Osteoarthritis
• Radial tunnel syndrome

Management ^[2]

• Advise patients that:
  • Symptoms usually spontaneously resolve within 6–12 months.
  • Using the affected limb normally will not cause damage.
  • Conservative management is usually sufficient.
• For more information, see “Management of insertional tendinopathies.”

Medial epicondylitis is an overuse injury of the forearm, especially the finger flexor tendons that originate in the medial epicondyle. Despite the term “epicondylitis,” there is no inflammation of the epicondyle; instead there is degeneration of the forearm tendons. ^[1][7]

Epidemiology ^[7][8]

• Most common between 30 and 50 years of age
• ♂ > ♀

Etiology ^[7]

• Most commonly due to repeated wrist flexion and forearm pronation (e.g., playing golf or overhead throwing)
• Can also be idiopathic

A FLexible game of golf allows Mulligans: repeated FLexion of the elbow (e.g., in golf) causes medial epicondylitis.

Clinical features ^[7][9]

• Pain in the medial elbow that radiates down the forearm (flexor muscles)
• Worsens with activity, particularly flexion of the wrist
• Reduced grip strength
• On examination, pain 5–10 mm distal and anterior to the epicondyle with possible soft tissue swelling ^[7]

Diagnosis ^[7][10]

• Clinical diagnosis based on history and provocation testing
• Provocation testing: Pain is elicited when the patient flexes the wrist against resistance, with the elbow held in extension.
• Consider assessing for Tinel sign to rule out coexistent ulnar neuritis. ^[7][11]
• For diagnostic uncertainty: Consider imaging. ^[6]
  • Initial test: x-ray
    • Excludes bone pathology
    • Calcification of the common flexor tendor or ulnar collateral ligament is visible in up to 25% of patients. ^[7]
  • Advanced imaging: ultrasound or MRI without contrast of the elbow

Differential diagnoses ^[7]

• Ulnar neuritis (also a common coexisting condition)
• Ligamentous instability

Management ^[1][7]

• Most medial epicondylitis resolves with conservative management.
• Wrist braces may provide symptomatic relief.
• For more information, see “Management of insertional tendinopathies.”

Iliotibial band syndrome is a common overuse injury of the distal portion of the iliotibial band (over the lateral femoral epicondyle).

Epidemiology

• Occurs in up to 12% of runners ^[12]
• ♂ > ♀ ^[13]

Etiology ^[12]

• Repetitive flexion and extension of the knee (e.g., from running, cycling)
• Inflammation may result from: ^[14]
  • Friction of band against lateral femoral condyle
  • Compression of connective tissue and fat beneath the iliotibial band
  • Chronic inflammation of the associated bursa

Clinical features ^[12]

• Pain in the lateral knee (due to friction of iliotibial band against femoral epicondyle)
• Shooting pain immediately after the foot strikes the ground (may be accompanied by a snapping sensation)
• Dull, constant pain at rest
• Tenderness approximately 2 cm proximal to the lateral joint line ^[15]
• Possible swelling at distal iliotibial band

Diagnosis ^[12][15]

• Clinical diagnosis based on history and provocation testing
• Provocation tests
  • Noble test
    • Patient lies on the unaffected side and flexes the affected knee to 90°.
    • Examiner exerts constant pressure on the lateral femoral epicondyle while extending the knee.
    • The test is positive if pain is elicited.
  • Alternative: Ober test ^[12]
• For refractory or recurrent pain: Obtain imaging.
  • Initial test: x-ray to exclude differential diagnoses ^[12][16]
  • Advanced imaging: MRI without contrast ^[12]

Differential diagnoses of iliotibial band syndrome ^[12]

• Osteoarthritis of the knee
• Patellar maltracking
• Stress fractures

Management ^[12][15]

• Most patients recover fully after 6 weeks of conservative management.
• After initial rest, exercise therapy is recommended.
• Surgery may be required for persistent pain.
• For more information, see “Management of insertional tendinopathies.”

Patellar tendonitis is an overuse injury of the patellar tendon at the distal portion of the patella. For information on patellar tendon rupture, see “Sports injuries.”

Epidemiology

• Typically affects athletes ^[17]
• ♂ > ♀ ^[18]

Etiology ^[1]

• Repeated jumping (e.g., volleyball, basketball)
• Risk factors include high BMI, limb-length discrepancy, and pes planus. ^[19]

Clinical features ^[18]

• Usually unilateral but can be bilateral
• Pain in the anterior aspect of the knee, localized to the inferior patella and proximal patella tendon ^[19]
• Symptoms worsen with knee flexion and prolonged activity.
• Tenderness when pressure is applied to the inferior border of the patella

Diagnosis ^[18]

• Clinical diagnosis based on history and provocation testing
• Provocation test: decline squat test ^[1][18]
  • Patient performs a single leg squat on a board or block at a declined angle of 25°.
  • If pain is reproduced, the test is positive.
• For refractory or recurrent pain: Obtain imaging. ^[16]
  • Initial test: x-ray (AP, lateral, tangential patella view) to exclude differential diagnoses
  • Advanced imaging: ultrasound or MRI without contrast ^[18]

Differential diagnoses of patellar tendonitis ^[18][19]

• Osgood-Schlatter disease
• Sinding-Larsen-Johansson syndrome
• Patellofemoral pain syndrome
• Meniscus tears

Management

• Initial management: physical therapy with strength training on a board or block at a declined angle ^[1][19]
• For more information, see “Management of insertional tendinopathies.”

Achilles tendinopathy (achillodynia) is an overuse injury of the Achilles tendon. Achilles tendon rupture is discussed separately. ^[1]

Epidemiology ^[20]

• Most commonly affects individuals 30–60 years of age
• ♂ = ♀

Etiology ^[1][21]

• Individuals (e.g., runners, other athletes) who have recently increased their exercise intensity
• Associated with fluoroquinolone use, especially in older adults ^[22]

Clinical features ^[22][23]

• Pain with load-bearing activity
  • Typically occurs in the morning or at the start of an exercise
  • Pain that persists at rest often indicates chronic disease.
• Tenderness on palpation may be:
  • At the insertion of the Achilles tendon (insertional tendinopathy)
  • 2–6 cm above the insertion of the Achilles tendon (midportional tendinopathy)

Diagnosis

• Clinical diagnosis based on history and provocation testing
• Provocation tests: performed with the patient lying prone with feet extending off the end of the examination table ^[23][24]
  • Arc sign
    • The clinician palpates the thickened portion of the tendon.
    • The patient plantar flexes and dorsiflexes the ankle.
    • The test is positive when the thickened portion of tendon moves relative to the malleoli.
  • Royal London test
    • The clinician palpates to locate the point of tenderness, then passively dorsiflexes the patient's foot.
    • The test is positive when pain decreases.
• For diagnostic uncertainty: Obtain imaging. ^[25]
  • Ultrasound
    • Initial study if there is high suspicion of Achilles pathology ^[25]
    • Findings: tendon thickening ^[22]
  • X-ray
    • Performed for heel pain of unknown origin ^[25]
    • Findings: calcification at tendon insertion ^[26]
  • Advanced imaging: MRI without contrast ^[1][23]

Differential diagnoses of Achilles tendinopathy ^[21][27]

• Retrocalcaneal bursitis
• Haglund exostosis
• Calcaneal apophysitis ^[28]
  • Inflammation and edema secondary to a stress fracture of the apophysis of the calcaneus
  • Causes heel pain, particularly on activity

Management ^[1][23]

• Two-thirds of patients respond to conservative management with physical therapy.
• Avoid corticosteroid injections because of the risk of tendon rupture.
• For more information, see “Management of insertional tendinopathies.”

Conservative management ^[1][15]

• Relative rest
• Ice
• Orthotic braces
• Physical therapy
• Topical or oral NSAIDs for 7–14 days (for dosages, see “Analgesia”) ^[1]

Physical therapy includes strength training with appropriate tendon loading to promote tendon repair. ^[1][15]

Refractory symptoms

• If pain persists for ≥ 3 months despite conservative therapy, consider referral to an orthopedic specialist. ^[1]
• Noninvasive treatment options include:
  • Corticosteroid injection
  • Platelet-rich plasma injections
  • Topical nitroglycerin
  • Extracorporeal shock wave therapy
• Surgical options include:
  • Ultrasound-guided debridement
  • Tendon resection
  • Open debridement ^[29]

Repeat corticosteroid injections may cause tendon rupture. ^[1]