Skip to Main Content

Knee pain is a common problem, accounting for 1.9 million visits to primary care practitioners and 1 million visits to emergency departments annually. By following a systematic approach in evaluating knee pain (which includes obtaining a thorough and directed history), focusing on specific questions, using the physical examination (sometimes with the assistance of diagnostic studies), and understanding knee anatomy (Figure 12–1), physicians are able to make the correct diagnosis and formulate an appropriate therapeutic strategy.

Figure 12–1.

Functional anatomy of the knee.

The first step in the evaluation of knee pain is a thorough history that includes the core elements outlined in Table 12–1. While obtaining a history, the following key questions should be addressed:

  • Has there been an acute injury?
  • Is a joint effusion present?
  • Is there evidence of osteoarthritis?
  • Are there mechanical symptoms?
  • Is there evidence of systemic disease?

Table 12–1. Knee Pain: Core Elements of the History.

The answers to these questions help the clinician narrow the differential diagnosis and formulate a strategy for a directed work-up of the knee pain.

The history should also determine whether the pain is localized to a specific region of the knee, which also can be a helpful guide to the cause of symptoms. The examiner should take into account the age and sex of the patient, both of which can influence the differential diagnosis. Finally, the clinician should bear in mind that pain can be referred to the knee from other sites, most notably the ipsilateral hip. Every patient with knee pain should have a careful examination of the hip.

General Approach to the Physical Examination

The general physical examination has 5 major components: observation of stance and gait, range of motion, palpation, examination for a knee effusion, and stability tests. After completing these general examinations and considering the patient’s history, the clinician can generate a differential diagnosis and focus the work-up accordingly (see specific injuries and conditions below).

Observation of Stance and Gait

Physical examination should start with observation of stance and gait. Can the patient bear weight on the affected leg? Is there a limp? Attention should be paid to medial or lateral translation of the ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.