• Clinical science

Collection of orthopedic conditions

Popliteal (Baker) cyst

  • Definition: swelling in the popliteal fossa between the medial head of the gastrocnemius muscle and the semimembranosus muscle that contains synovial fluid
  • Etiology
    • Inflammation of the synovium, which stimulates excessive production of synovial fluid
    • Risk factors: inflammatory, degenerative, or traumatic intra-articular changes in the knee joint (e.g., rheumatoid arthritis, arthritis, meniscal lesions)
  • Anatomy: The borders of the popliteal fossa include:
  • Clinical features
    • Most cysts are asymptomatic and detected only incidentally on imaging.
    • If symptomatic: Swelling of the popliteal fossa; and posterior knee pain are common.
  • Diagnostics
    • Usually a clinical diagnosis
    • Plain x-ray or ultrasound; are commonly used as initial imaging modalities and reveal a soft tissue mass (x-ray) or an anechoic lesion (ultrasound).
  • Complications: cyst enlargement and rupture → leakage of synovial fluid caudally into the lower leg muscles
  • Treatment
    • Asymptomatic cysts do not require treatment.
    • Symptomatic cysts
      • Treat underlying pathology of the knee joint
      • If symptoms persist, intra-articular injection of glucocorticoids can control inflammation.
      • Surgical resection for symptomatic cysts that persist despite treatment.

A popliteal cyst can be mistaken for a deep vein thrombosis or thrombophlebitis of the lower leg!

References:[1][2]

Bursitis

References:[3][4][5]

Meniscal cyst

  • Definition: a collection of synovial fluid in or around the meniscus
  • Etiology: secondary to a meniscal tear synovial fluid becomes encysted
  • Clinical features
    • Pain and swelling
    • Decreased range of motion of the knee
    • Chronic meniscal tears → locking (decreased extension of the knee) and popping (knee joint laxity)
  • Diagnosis
    • Clinical diagnosis
    • MRI can aid in management if surgical intervention is indicated.
  • Treatment
    • Conservative management with rest, pain control, and crutches
    • Surgical intervention is indicated in refractory cases that do not respond to conservative management, or if there are mechanical symptoms (locking, popping) or tears in an avascular zone.

References:[6][7][8]

Stress fracture

  • Definition: complete bone fracture caused by repetitive stress without underlying bone pathology or disease affecting the bone
  • Etiology: Increased load or frequency of physical activity can facilitate bone resorption.
  • Risk factors
    • Repetitive high intensity physical activity
    • Improper technique during physical activity
    • Caloric restriction; , especially in patients with anorexia nervosa
    • Decreased bone density (e.g., bisphosphonate use)
    • Calcium deficiencies
    • Female sex
  • Clinical features:
    • Most common; in the lower extremities (metatarsals; , also the tibia; , fibula; , and navicular bones); less common in the upper extremities (humerus, scapula, ribs)
    • Acute pain with activity (worsens with loading or stress, relieved with rest)
    • Bone tenderness, erythema, or soft tissue swelling
  • Diagnosis
    • Clinical diagnosis
    • Conventional x-rays can appear normal in the first 2–3 weeks.
    • MRI for definitive diagnosis: detects fracture line , surrounding tissue damage, and edema
  • Treatment
    • Pain control: acetaminophen, ice packs
    • Rest; , physical therapy, and risk factor modification (improved nutrition, calcium, and vitamin D supplementation)
    • Surgery in refractory cases

References:[9][10][10][11]

Genu valgum

  • Definition: valgus (lateral) misalignment of the knee, resulting in a knocked knee deformity
  • Etiology
    • Physiological: normal at 2–5 years of age; associated with normal stature, bilateral symmetry, a tibiofemoral angle within two standard deviations of the mean for age, and no clinical symptoms
    • Pathological: post-traumatic; (e.g., distal femoral fracture), metabolic disorders; (e.g., rickets; , mucopolysaccharidosis), skeletal dysplasias (e.g., chondroectodermal dysplasia), or neoplasms
  • Clinical features of pathological valgus
    • Unilateral valgus that is progressive (after 4–5 years of age) or persistant (after 7 years of age)
    • Severe valgus: > 8 cm between the medial malleoli, with patellae facing forward and femoral condyles together
    • Gait abnormalities and congenital flat feet
    • Features suggestive of an underlying disease (e.g., unilateral deformity, short stature, fever, knee or foot pain, abnormal swelling)
  • Diagnosis: : if pathological valgus is suspected, imaging and/or metabolic evaluation to determine underlying disease
  • Treatment
    • Physiological valgus may improve by the age of 7 and should be managed with close observation and reassurance.
    • Medical treatment of the underlying pathology
    • For persistent symptoms in patients older than 10, surgery is indicated.

References:[12][13]

Genu varum

  • Definition: varus (medial) misalignment of the knee, resulting in a bow leg deformity; common in children
  • Etiology
    • Physiological: normal at birth; associated with normal stature, bilateral symmetry, and no clinical symptoms
    • Pathologic varus: : result of Blount disease, metabolic disorders (e.g., rickets; ), skeletal dysplasias, or neoplasms
  • Clinical features of pathological varus
    • Bowing that is progressive or persistant (after 3 years of age)
    • Severe bowing: > 6 cm between the femoral condyles with the patellae facing forward and medial malleoli together
    • Gait abnormalities
    • Features suggestive of an underlying disease (e.g., unilateral deformity, short stature, fever, knee or foot pain, abnormal swelling)
  • Diagnosis: if pathological varus is suspected, imaging and/or metabolic evaluation to determine underlying disease
  • Treatment
    • Physiological varus usually improves by 24 months and should be followed by close observation.
    • Treatment of the underlying pathology
    • For persistent symptoms; that do not respond to medical management, surgery is indicated.

References:[14]

Greater trochanteric pain syndrome

  • Etiology: gluteus medius or minimum muscle tendinopathy
    • Involvement of the trochanteric bursa is possible, although rare.
    • May also be associated with snapping hip (coxa saltans) or trauma
  • Clinical features
    • Common cause of lateral hip pain
    • Pain is usually localized to the greater trochanter at the proximal end of the femur.
    • Tenderness to palpation over the greater trochanter
    • Pain is triggered by resisting active abduction or standing only on the affected leg.
  • Diagnosis
    • Imaging may be indicated if the diagnosis is unclear, if an underlying pathology is suspected, or in cases that do not respond to initial treatment.
      • Ultrasound: may show thickening of the iliotibial band, tendinosis of the gluteal muscles, and or trochanteric bursitis
      • MRI: to evaluate for an underlying pathology or prior to surgery
  • Treatment
    • Mainly conservative (e.g., relative rest, NSAIDs)
    • In refractory cases, surgery is indicated.

Forearm fractures

Colles and smith fractures

See distal radius fractures.

Monteggia fracture

  • Definition: proximal ulnar shaft fracture with concomitant anterior dislocation of the radial head
  • Mechanism of injury
    • Low-energy trauma, e.g., fall on outstretched and pronated forearm
    • High-energy trauma, e.g., direct blow to the forearm from a motor vehicle accident
  • Clinical features
  • Diagnosis: X-ray shows a fracture of the proximal third of the ulna with anterior dislocation of the radial head.
  • Treatment
    • In children with uncomplicated fractures: closed reduction and casting
    • In adults or complicated fractures : open reduction and internal fixation (plating, K-wire fixation)

Galeazzi fracture

  • Definition: radial shaft fracture with disruption of the distal radioulnar joint; more common in children
  • Mechanism of injury: fall on outstretched and pronated forearm
  • Clinical features
    • Pain, deformity, and limited range of movement at the distal-third radial fracture site and wrist joint
    • Anterior interosseous nerve (AIN) palsy can occur.
  • Diagnosis: X-ray shows a fracture of the junction of the distal third and middle third of the radius shaft with subluxation or dislocation of the distal radioulnar joint and a tear in the interosseous membrane.
  • Treatment
    • In children with uncomplicated fractures: closed reduction and casting
    • In adults or complicated fractures : open reduction and internal fixation (plating, K-wire fixation)

Other forearm fractures

References:[15][16][17][18][19]