Special Tests: Knee - Meniscus Tears, Patellofemoral Pain, and Fracture

Special Tests Covered in this Lesson:

• Meniscus Tear Tests
  • McMurray's Test
  • Thessaly's Test
• Patellofemoral Pain Syndrome (PFPS) Test-item Cluster
  • Eccentric Step Down Test
    • Functional Activities (Squats, kneeling, stair-climbing)
  • Resisted Knee Extension
• Red Flags (Fracture)
  • Ottawa Knee Rules

Knee special tests for meniscus tears, patellofemoral pain syndrome (PFPS), and knee fracture have enough accuracy to offer some clinical utility. Meniscus tears are generally reported following an acute knee injury, may occur on one side (e.g. lateral meniscus or medial meniscus), and may be accompanied by knee joint effusion (swelling). Generally, PFPS is a complaint of knee pain in the proximity of the patella that accompanies quadriceps contraction during functional tasks. The pain often begins spontaneously, or gradually, without a specific incident or acute injury. And, knee joint fracture, although relatively rare, may occur following direct trauma to the knee, or landing on the knee(s) during a fall. Clinical movement professionals (physical therapists, physical therapy assistants, chiropractors, occupational therapists, athletic trainers, etc.) should be aware of the special tests for these conditions to aid in the development of an accurate prognosis, monitor concordant signs, and identify red flags. Note, special tests for the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament, and lateral collateral ligament are included in the course Special Tests: Knee Ligament Tests .

Summary:

The combination of patient history, physical examination, special tests, and radiographs has been investigated for the diagnosis of meniscus tear; however, study results are mixed (1, 4 - 21). Generally, the accuracy of special tests and examinations for the diagnosis of a meniscus tear is questionable. A diagnosis of a meniscal lesion without the confirmation of arthroscopy should likely be viewed with healthy skepticism. Based on available research Thessaly's Test may have the highest sensitivity (and potentially accuracy) (23, 34, 35, 40, 41); however, McMurray's Test is also recommended due to the relatively high specificity reported in a larger body of studies.

Although tests for patellofemoral pain syndrome (PFPS) have relatively high specificity, PFPS is a relatively broad diagnosis (41-45). A cluster (Cook's Cluster) including the Knee Extension Test, pain with palpation, and pain during a functional task (e.g. Eccentric Step Down Test ) may increase the accuracy of diagnosing PFPS (44); however, the broad diagnosis of PFPS may not be helpful for directing treatment. These tests are likely best used in the cluster mentioned, and the test that replicates the patient's complaints or symptoms (concordant sign) may be repeated throughout treatment as a pre/post-intervention reassessment.

The Ottowa Knee Decision Rules have been added to this course as a screen for the potential "Red Flag Issue" of knee fracture. It is unlikely that outpatient orthopedic professionals will use this cluster often, but it is worth having access to a quick reference in case knee fracture is suspected. Note, the diagnosis of fracture is not necessarily the goal of this cluster. The cluster of signs is highly sensitive (not necessarily specific), indicating that fracture is a possibility, and that referral for imaging is needed prior to additional treatment (46, 47).

Brookbush Institute Recommendation:

The Brookbush Institute recommends that all clinical professionals (physical therapists, physical therapy assistants, chiropractors, occupational therapists, athletic trainers, etc.) are aware of these tests. The Thessaly's Test (with confirmation from McMurray's Test ) may be beneficial for diagnosing meniscal tears and developing a more accurate prognosis for treatment. The Cook's Cluster may provide some clinical utility for identifying a concordant sign that can be used throughout treatment as a pre/post-intervention reassessment. And, being aware of the Ottowa Knee Decision Rules are advised for use when a knee fracture is suspected.

For an Introduction to Special Tests

• For an introduction to Special Tests including definitions of specific terminology, what special tests measure, accuracy (specificity, sensitivity, reliability, etc.), how we chose the tests in each special test course lessons, and best practice recommendations:
• Special Tests: Introduction

Courses covering Special Tests for the Knee

• Special Tests: Knee Ligament Tests
• Special Tests: Knee - Meniscus Tears, Patellofemoral Pain and Fracture