Vipul Shah

Group D

Family Syllabus—Ortho pp. 450-465

Ottawa Knee Rule (p. 450)

  • Used to determine whether X-rays are needed in acute knee injuries, and can reduce use of X-rays by 28%
  • Knee X-rays are needed only if there are any of the following:
  • Age 55 or older
  • Isolated tenderness of the patella (no other bone tenderness)
  • Cannot flex knee 90 degrees
  • Cannot bear weight for four steps immediately and in the ER
  • Had a sensitivity of 1.0 and a negative predictive value of 1.0, results in shorter ER stays and lower costs

Acute Knee Injuries Part I—History and Physical (p. 451-457)

  • History should cover the following:
  • Type of activity at time of injury
  • Position of knee, leg, foot at time of injury
  • Mechanism of injury (direct blow, etc.)
  • Whether “snap” or “pop” was heard (I guess “crackle” doesn’t do knees)
  • Location of pain
  • How soon swelling developed
  • Whether pt could continue activity afterwards
  • Previous history of knee injury
  • Physical Exam
  • Uninjured knee should be examined first for comparison
  • Should examine as soon as possible before there’s too much swelling/pain
  • Note whether edema is extra-articular (from bursa or sprain of MCL or superficial fibers) or intra-articular (from cruciate ligament or meniscal tear)
  • Range of Motion—test passive/active ROM, normal flexion is 135-145 deg, normal extension is 0 deg, look also for crepitation or signs of patellar pain
  • Palpation
  • Start at the tibial tuberosity, go up the patellar tendon and around the patella
  • Then palpate bursae, joint line spaces (starting with uninjured side)
  • Internal rotation helps palpation of medial meniscus, external rotation helps palpation of lateral meniscus
  • Tenderness superior to anteromedial joint may be from patellar problems
  • Palpate iliotibial band while knee is extended
  • Patellofemoral Mechanism—acute patellar instability is assessed by patellar apprehension test—push laterally on patella and see if pt is apprehensive about it (or kicks you in the face)
  • Specific Maneuvers
  • Varus and valgus testing, in both full extension and 30 deg flexion, test strength of collateral ligaments
  • Four tests for cruciate ligaments—Lachman and pivot shift (ACL), and posterior drawer and tibial sag (PCL)
  • Anterior drawer test is very insensitive (22%) for ACL tear
  • While pivot shift is more sensitive than Lachman, it is more painful, so Lachman is the test of choice for ACL
  • Posterior drawer test is very good for assessing PCL
  • Testing for menisci is of little value, but you can use bounce test, McMurray’s, Apley’s grind, or duck walk
  • Lachman test—30 deg flex, pulling lower leg forward
  • Pivot shift test—flexing knee while leg is internally rotated and valgus (inward) stress is applied
  • Posterior drawer test—90 deg flex, pushing lower leg back
  • Tibial sag test—90 deg flex, support leg from ankle, can see posterior sag obscuring tibial tubercle on lateral view
  • Bounce test—extend and hold leg by the heel, flex knee and let it fall back passively
  • McMurray’s test—flex 45 deg, palpate medial joint while applying valgus stress, then varus stress, then extend knee while still pushing out (varus)—a click means positive test; test is done in opposite manner for lateral meniscus
  • Apley’s grind test—pt prone, 90 deg flex, push down on heel (axial) while rotating internally and externally—however, torn MCL/LCL will also cause pain, so repeat without axial load, and it won’t be painful if only meniscus is damaged

Acute Knee Injuries Part II—Diagnosis and Management

  • There are 4 important soft tissue injuries—patellar instability, meniscal tear, cruciate and collateral ligament sprains
  • Patellar Injury
  • Must differentiate acute pain as dislocation or traumatic bursitis
  • Ripping/tearing sensation is often associated with dislocation
  • Dislocation/subluxation does not always come from trauma, traumatic bursitis does
  • X-rays are essential for traumatic patellar injury—28-52% are associated with fracture
  • Initial episodes usually respond favorably to physical therapy, bracing/taping, and rest
  • The younger the patient, the more likely to have recurrent dislocation/subluxation
  • Pts usually go through a maintenance rehab program to strengthen/stabilize patella
  • After 6 mos if not satisfactory recovery, surgery may be considered
  • If there is dislocation and fracture, surgery should be initial option
  • Meniscal Injury
  • No adequate clinical test available
  • 1/3 of meniscal injuries are associated with ACL tear
  • May be tough to see b/c of swelling, so reeval after one week of RICE, NSAID therapy
  • The majority of meniscal tears require referral to ortho for surgery
  • MRI is very good at finding meniscal tears, but arthroscopy still may be necessary to determine type and extent of injury
  • If they get arthroscopic meniscectomy, they can return to sports in one month or so, but meniscal repair may take 4-6 months
  • Collateral Ligament Injury
  • Usually what is meant by a “sprained knee”
  • Typically involves direct trauma to the contralateral side of the knee
  • Injuries to MCL usually occur at proximal origin, so tenderness is at distal femur extending to joint line
  • LCL sprains are less common and more likely to be missed
  • Sprains are classified as grade I, II, III
  • Grade I—microtears, <5 mm increased joint opening, no instability
  • Grade II—partial macrotear, instability, significantly increased joint opening
  • Grade III—complete macrotear
  • Tx for Grades I, II—RICE, NSAIDs for 24-72 hrs, physical therapy, bracing for 4-6 weeks for Grade II
  • Tx for Grade III—conservative management for 4-8 weeks with emphasis on physical therapy and bracing
  • Cruciate Ligament Injury
  • Hemarthrosis following acute trauma is associated with ACL injury 75% of the time
  • 3 factors to consider when determining whether to reconstruct—pt activity levels, pathoanatomical factors (structural damage), biomechanical factors (instability)
  • Athletic pts should have reconstruction, while sedentary pts may do better with physical therapy and bracing
  • Fewer than half of those who don’t have surgery can return to their sport at the same level, and ¾ have activity-related symptoms
  • Injuries to the PCL are uncommon in sports, and are usually from trauma to the proximal tibia when the flexed knee is decelerated rapidly
  • Isolated interstitial PCL tear should be managed conservatively, even in athletes, but if there is associated bony avulsion surgery may be needed

There are several flow charts for deciding therapy. They’re very detailed, but it might be good to look over them.