From the Guidelines
For chronic knee pain evaluation, I recommend starting with radiographs of the knee as the initial imaging modality in patients greater than or equal to 5 years of age, as suggested by the American College of Radiology Appropriateness Criteria 1. This approach is based on the principle of using the least invasive and most cost-effective method first, while also considering the high prevalence of osteoarthritis as a cause of chronic knee pain.
Key Considerations
- Radiographs are usually appropriate for the initial imaging of chronic knee pain in patients greater than or equal to 5 years of age 1.
- MRI knee without IV contrast may be considered in patients with chronic knee pain when initial knee radiographs are normal or demonstrate a joint effusion 1.
- A comprehensive approach to chronic knee pain evaluation should also include a detailed medical history and physical examination to identify potential underlying causes and contributing factors.
- Laboratory tests, such as complete blood count, inflammatory markers (ESR, CRP), and rheumatoid factor, may be helpful in identifying inflammatory causes of chronic knee pain.
Treatment Options
- Conservative measures, such as acetaminophen or NSAIDs, should be considered as first-line treatment for chronic knee pain.
- Physical therapy, focusing on quadriceps and hamstring strengthening exercises, can help improve functional outcomes and reduce pain.
- Weight management and topical treatments, such as diclofenac gel, may also be beneficial in reducing knee load and providing localized relief.
- Intra-articular corticosteroid injections or hyaluronic acid injections may be considered for persistent pain, while surgical options like arthroscopy or knee replacement should be reserved for cases where conservative measures have failed.
Prioritizing Patient Outcomes
- The primary goal of chronic knee pain evaluation and treatment is to improve patient outcomes, including reducing pain, improving function, and enhancing quality of life.
- A patient-centered approach, taking into account individual preferences and values, is essential in developing an effective treatment plan.
- By prioritizing morbidity, mortality, and quality of life, healthcare providers can ensure that patients receive evidence-based care that addresses their unique needs and promotes optimal outcomes.
From the FDA Drug Label
Intra-articular administration: A single local injection of triamcinolone acetonide is frequently sufficient, but several injections may be needed for adequate relief of symptoms. Initial dose: 2. 5 mg to 5 mg for smaller joints and from 5 mg to 15 mg for larger joints, depending on the specific disease entity being treated. For adults, doses up to 10 mg for smaller areas and up to 40 mg for larger areas have usually been sufficient.
The evaluation for chronic knee pain may involve intra-articular injection of triamcinolone acetonide. The initial dose is typically between 2.5 mg to 5 mg for smaller joints and 5 mg to 15 mg for larger joints, with a maximum dose of 40 mg for larger areas 2.
- Key considerations:
- Dose adjustment: The dose may need to be adjusted based on patient response and duration of relief.
- Joint aspiration: Aspiration of excess synovial fluid may be necessary to aid in pain relief and prevent dilution of the steroid.
- Local anesthetic: Use of a local anesthetic may be desirable to minimize discomfort during the injection.
- Important safety information:
- Infection risk: Injection into an infected site should be avoided, and appropriate examination of joint fluid is necessary to exclude a septic process 2.
- Osteoporosis risk: Corticosteroids may increase the risk of osteoporosis, particularly in patients at increased risk, such as postmenopausal women 2.
From the Research
Evaluation of Chronic Knee Pain
The evaluation of chronic knee pain involves a thorough history and physical examination to localize the source of inflammation or injury 3. Key aspects of the patient history include:
- Age
- Location, onset, duration, and quality of pain
- Associated mechanical or systemic symptoms
- History of swelling
- Description of precipitating trauma
- Pertinent medical or surgical history
Physical Examination
A systematic approach to examination of the knee includes:
- Inspection
- Palpation
- Evaluation of range of motion and strength
- Neurovascular testing
- Special (provocative) tests 4
Imaging and Diagnostic Tests
Radiographic imaging should be reserved for chronic knee pain (more than six weeks) or acute traumatic pain in patients who meet specific evidence-based criteria 4. Musculoskeletal ultrasonography and magnetic resonance imaging (MRI) can be used to evaluate the knee, but MRI is rarely used for patients with emergent cases and should generally be an option only when surgery is considered or when a patient experiences persistent pain despite adequate conservative treatment 4, 5.
Diagnosis and Management
The diagnosis of chronic knee pain can be confirmed by a combination of clinical history, physical examination, and radiographic imaging 6. The management of chronic knee pain depends on the underlying cause, but first-line treatment often consists of conservative management, including exercise therapy, weight loss, education, and self-management programs 7. Surgical referral can be considered for patients with end-stage osteoarthritis or severe traumatic meniscal tears 7.
Common Causes of Chronic Knee Pain
Common causes of chronic knee pain include:
- Osteoarthritis (OA)
- Patellofemoral pain
- Meniscal tears These conditions can be diagnosed clinically and can be associated with significant disability 7.