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109: Knees, Foot & Ankle and Something Special Next Week

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Disorders of the Knee

Fractures & Dislocations

  • History of Trauma
  • Labs studies and physical exam findings
    • Palpation, strength and range of motion if there is no obvious deformity
    • Straight leg raise if a patella fracture is suspected.
    • X-ray
    • CT
  • Treatment
    • Anatomical reduction
    • Immobilization
    • Surgical repair
      • Patella fracture – wired or screws
      • Distal femur – plate and screws or a femoral nail
      • Tibial plateau fracture – Nasty fracture requiring multiple screws and plates.

Osgood-Schlatter Disease

  • Apophysitis of the tibial tubercle
  • Most frequently in 13 year old physically active boys

Clinical Presentation

  • My son is complaining of anterior knee pain

Labs, Studies and Physical Exam Findings

  • Enlarged tibial tubercle
  • Pain is reproducible by resisted extension of the knee

Treatment

  • NSAIDS
  • It is self limiting, but not until the growth plates have closed
  • RICE
  • Physical therapy

Meniscus Injury

  • Meniscus is from the Greek for crescent
  • The medial and lateral meniscus provide cushion and stability for the knee
  • Medial meniscus tears are among the most common knee injuries
  • May be degenerative or traumatic
  • Traumatic injury usually occurs secondary to twisting the knee with the foot planted

Clinical Presentation

  • My knee has been bothering more for weeks
  • My knee locks and pops
  • My knee gives out

Labs, Studies and Physical Exam Findings

  • Joint line tenderness
  • Patient may not be able to fully extend the knee
  • Effusion of the knee
  • McMurray – Put the patient through passive flexion and extension of the knee while applying pressure in order to externally rotate it.  Repeat the maneuver with the tibia rotated internally.
  • Apply – The patient is prone on the table with the knee flexed to 90 degrees.  You then press the patients heel directly towards the floor while internally and externally rotating the foot.
  • Thessaly test – Patient stands on one leg and flexes knee to 20 degrees.  The patient then internally and externally rotates the knee.  Repeat the maneuver with the tibia rotated internally.
  • X-ray
  • MRI

Treatment

  • RICE
  • Physical Therapy
  • Surgical correction
    • Arthroscopy

Anterior Cruciate Ligament (ACL) Injury

  • The ACL prevents anterior translation of the tibia
  • The most commonly injured knee ligament
  • Women doing similar activity as men have a higher risk of an ACL injury
    • Think women’s soccer

Clinical Presentation

  • I felt a pop in my knee and now it feels unstable especially coming down stairs

Labs, Studies and Physical Exam Findings

  • Knee effusion
  • Anterior drawer – patient is supine with the knee flexed to 90 degrees.  You sit on the patient’s foot and pull on their tibiae.  If it moves forward significantly more than the unaffected side this is a positive test.
  • Lachman test – the patient’s knee should be in 30 degrees of flexion.  You then stabilize the distal femur with one hand and pull on the proximal tibia with the other.  (If asked the Lachman test is the single best choice)
  • X-ray
  • MRI
  • Ultrasound

Treatment

  • RICE
  • Physical Therapy
  • Surgical correction

Posterior Cruciate Ligament (PCL) Injury

  • The PCL prevents posterior translation of the tibia
  • Occurs secondary to a direct blow of a flexed knee – think hitting the dashboard in a motor vehicle accident

Clinical Presentation

  • Knee pain
  • Instability

Labs, Studies and Physical Exam Findings

  • Effusion
  • Posterior sag sign – patient is supine and hips and knees are flexed to 90 degrees.  Look for a posterior translation of the affected tibia and no clear tibial step off
  • Posterior drawer test – with knee flexed to 90 degrees push on the proximal tibia
  • X-ray
  • MRI
  • Ultrasound

Treatment

  • RICE
  • Physical Therapy
  • Surgical correction

Collateral Ligament Injuries

  • Medial collateral ligament (MCL) stabilizes the knee against valgus stress
  • Lateral collateral ligament (LCL) stabilizes the knee against valgus stress
  • Cause is often a direct blow

Clinical Presentation

  • I felt a pop in my knee and now I’m having trouble walking

Labs, Studies and Physical Exam Findings

  • Medial joint line tenderness
  • Effusion
  • Apply valgus stress to the knee at 30 degrees of flexion and 0 degrees of flexion
  • X-ray
  • MRI

Treatment

  • RICE
  • Physical Therapy
  • Surgical correction

Disorders of the Ankle/Foot

  • Weight bearing films whenever possible
  • Ankle sprain – Most common ankle sprain involves the anterior talofibular ligament.
  • Ankle fracture can involve the lateral malleolus (fibula) and the medial malleolus (tibia)
  • 5th metatarsal avulsion fracture
  • Jones fracture at or just distal to the Metaphyseal-diaphyseal junction of the 5th metatarsal.
    • These are important because they have a high rate of nonunion
  • Achilles tendon rupture
    • “It feels like someone kicked me or shot me from behind”
    • Often a palpable gap in the tendon
    • Thompson Test – If you squeeze the calf and the foot does not move it is an indication of an achilles tendon rupture
  • Posterior tibial tendon insufficiency
  • Plantar fasciitis
  • Lisfranc –
    • A disruption of the medial cuneiform and the base of the second metatarsal
    • High energy injury
    • Missed diagnosis will result in chronic pain

Compartment Syndrome

  • Compartments are created by layers of fascia which do not stretch
  • A insufficient blood supply to an area of the body due to an increase in pressure within a compartment
  • Blood flow requires a pressure gradient. A backup of blood in the system causes fluid to “leak” from the vessels compounding the problem
  • Compartment syndrome usually occurs after trauma
  • Most commonly seen in tibia fractures

Clinical Presentation

  • This is often after surgery or other trauma
  • 6 P’s of of compartment syndrome
    • Pain is often the first sign
    • Paresthesia
    • Paralysis
    • Pulselessness
    • Pallor
    • Poikilothermia – cold limb

Labs, Studies and Physical Exam Findings

  • Clinical diagnosis using the 6 P’s
  • Measurement of intracompartmental pressure

Treatment

  • Remove the cast!!!
  • Fasciotomy