Knee pain is a very common problem. Inmost cases, a good history and a careful

physical exam are the keystone for diagnosis andfurther treatment (Table 1).1-3

What about clinical history?

There are several factors at play here:• Age, as osteoarthritis (OA), crystal deposition

arthritis, and periarticular disorders are themost common causes of knee involvement inthe elderly.

Focus on CME at the University of Alberta

By Cecilia P. Chung, MD; andAnthony S. Russell, MB, BCh, FRCPPresented at The Rheumatology Update, November 2, 2002

The Canadian Journal of CME / September 2003 143

Silvia’s aching knee

Silvia, 66, presents to her family physician with atwo-year history of right knee pain. During the lastmonth her pain has been more severe. It is worsewhen walking and climbing stairs, and is relievedby resting. She has no morning stiffness.

Anti-inflammatories have only partially relievedSilvia’s symptoms. There is no previous history oftrauma. Her medical history includes hypertensionand a bleeding duodenal ulcer from 20 years ago.

Her gait is normal on examination. No wasting ofthe right quadriceps is detected, and the right kneeshows no redness, warmth, instability, or effusion.There is crepitus with some tenderness over themedial joint line, and full range of movement. Herright hip movement is within normal limits, and herblood pressure is 140/95 mmHg. Silvia weighs 200pounds and is five-foot-seven. The rest of her examis unremarkable.

In this article:

1. What information should I get from the clinical history and the physical exam?

2. What are the treatment methods?

3. What is the role of physical therapy?

What Do I Do?

Painful Knee:

• Onset, as a fracture or internal derangementshould be ruled out if the pain began within sec-onds or minutes of the injury. Acute mensicalinjuries also involve easily identifiable precipi-

tating events often followed by an associatedlimited range of movement.1 Pain that beginswithin hours could indicate an infection, gout,pseudo-gout or other crystal deposition dis-eases. A history of insidious pain that beginswithin weeks or months, and an epidemiologicrisk may suggest OA or periarticular rheuma-tism.

• Past medical history of acute attacks with red-ness, swelling, and pain that were relieved withanti-inflammatory pills or spontaneously aftera few days should suggest crystal depositionarthritis. Use of anticoagulants could be relat-ed to hemarthrosis.

• Current or recent use of corticosteroids, espe-cially as long-term courses and/or in highdoses, increases the risk of avascular necrosis.

• Other characteristics of the pain, which includepain that worsens in the morning or during thesecond half of the night suggests an inflamma-tory condition; on the other hand, pain thatincreases with exercise suggests a mechanicalcomponent.

• Severity of pain, as knee pain with sudden onset(especially if it occurs at rest, disturbs sleep or

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146 The Canadian Journal of CME / September 2003

Dr. Russell is a professor ofmedicine, rheumatic diseaseunit, University of Alberta, andstaff rheumatologist, Universityof Alberta Hospital, Edmonton,Alberta.

Table 1

Etiology of knee pain

Extra-articular• Pre-patellar bursitis

• Anserine bursitis

• Patellar tendonitis

• Iliotibial band friction

• Popliteal tendonitis

• Pes anserinus tendonitis

Monoarticular

• Septic: For acute monoarthritis the causes aremainly common bacteria, for chronic monoarthritismycobacteria and fungus would need to be excluded.

• Crystal: Gout, pseudo gout, hydroxyapatite or calcium oxalate deposition.

• Traumatic: Fracture, internal derangement,hemarthrosis, ligamentous injuries.

• Mechanical: Osteoarthritis, patellofemoral syndrome.

• Other: Hemophilia, avascular necrosis, pigmented illonodular synovitis and synovioma, synovial chondromatosis

Monoarticular onset of a systemic disease• Rheumatoid arthritis• Seronegative spondyloarthropathies: mainly Reiter’s

syndrome and psoriatic arthritis.• Sarcoid arthritis

Others• Popliteal cysts• Referral pain

Adapted from:

1. Graham G, Fanclough JA: The knee. In: Klippel and Dieppe (ed): Rheumatology 2nd Edition. Mosby International, 1998, pp 4.11.1-14.

2. McAlindon TE: The knee. Best Pract Res Clin Rheumatol 1999; 13(2):329-44.

3. Hawkins, RA: Approach to the patient with monoarticular symptoms. In: West SG (ed):Rheumatology Secrets. Hanley & Belfus Inc. 1997, pp 74-9.

Dr. Chung is a clinical research fellow, University of Alberta,Edmonton, Alberta.

is severe) requires investiga-tion.2

• Symptoms associated with thepain, for example:- Fever (mostly in infections)

could also be present in crystal and inflammatory arthritis.

- Inflammatory low back pain, skin rash, diarrhea,urethral discharge, and conjunctivitis should suggest seronegative

spondyloarthropathies (ankylosis spondylitis,psoriasis, Reiter’s syndrome).

What about the physical exam?

Important information should be obtained from:• Inspection: Abnormalities in the gait are main-

ly associated with structural pain. Malalignmentas genu varus or genu valgus can also be detect-ed during the inspection (Figure 1). Quadricepswasting occurs very quickly with disuse.

• Palpation: Warmth, soft-swelling and tender-ness are the classic signs of inflammation. A

small effusion can be detected bya bulge test. Medium to largeeffusions are detected by the taptest. Remember, the knee is usu-ally cooler than the rest of thelower extremity.• Joint movement: Pain withactive movement usually is relat-ed to joint involvement. A crepi-tus sensation with movement isassociated with OA. A drawertest is used to examine the cruci-ate ligaments, and we should also

look for integrity of the collateral ligaments.4

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The Canadian Journal of CME / September 2003 147

Figure 3. Chondromatosis.Figure 2. Chondrocalcinosis and osteoarthritis.

Figure 1. Genu varus.

LUCKY DUCKFind out why on page 44

• Other joints: It is important to examine all theother joints, especially the hip. Pain can be dueto referred pain from hip pathology.5

What test should be includedfor a patient with acutemonoarthritis?

Arthrocentesis should be done in all patients withacute monoarthritis. The synovial fluid analysisis by far the most important diagnostic test for

isolating germs in septic arthritis, to detect crys-tals when a hemarthrosis has to be ruled out, andto differentiate inflammatory from non-inflam-matory arthritis.

What about other auxiliary exams?

X-rays are useful in ruling out fractures,osteonecrosis, OA, chondrocalcinosis and osteo-chondromatosis (Figures 2 and 3). It is important

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148 The Canadian Journal of CME / September 2003

Oral medication

• Non-opioid analgesics: Acetaminophen has beenproven in a placebo control study, and are still thefirst treatment of choice in osteoarthritis (OA)primarily for its safety. It is moderately effective.7

• Opioid analgesics: Such as codeine,dextropropoxyphene, tramadol and morphine. All areeffective, but they are also usually associated withconstipation, central nervous system adverse events,and physical dependence. Narcotics for pain controlwould be valuable primarily when surgery iscontraindicated because of comorbidities.

• Nonsteroidal anti-inflammatory drugs: They havebeen shown to be effective, especially in OA, buthead-to-head comparison of equipotent doses ofvarious non-steroidal anti-inflammatory drugs(NSAIDs) have not shown any to be superior.8

NSAIDs are widely used for inflammatory conditionsand soft tissue lesions.

• Coxibs: Their efficacies in knee OA have alreadybeen shown. Rofecoxib, celecoxib, etoricoxib, andvaldecoxib control the pain, as do traditional NSAIDs,and reduce the risk of gastrointestinal bleeding.Besides that, physicians should use the sameprecautions as with traditional NSAIDS when dealingwith patients with comorbidities, such ashypertension, heart, and/or renal failure.

• Glucosamine: A randomized controlled clinical trialshowed glucosamine sulphate was superior toplacebo as a symptom modifier in patients with OA.Doses of 1500 mg per day are recommended.9 It maydecrease radiographic progression.

Injections

• Corticosteroids: There is some evidence of a short-term benefit of local steroid injections, butrepeated injections are rarely useful. Five of eightrandomized controlled trials, versus placebo,reported a significant short-term benefit of steroidswhen used in patients with OA of the knee.Intra-articular steroids have a risk of post injectionflares, skin atrophy, and systemic effect. Even thoughthe risk of introducing an infection is uncommon, itcould result in severe morbidity, and that should bestated to the patient.

• Viscosupplementation: This consists of the intra-articular injection of cross linked hyaluronic acid,which is a component of synovial fluid that isdiminished in patients with OA. Randomizedcontrolled trials have shown high molecular weightcross linked hyaluronic acid is superior to placebo,not only in pain relief, but in function. It seems to besuperior to corticosteroids in the long term.

Table 2

Treatment of knee pain

to request bilateral and, if looking for OA, weight-bearing films to allow comparison and to detecteven mild space narrowing.

On the other hand, X-rays are unhelpful inassessing soft tissue injury. In meniscal lesions,magnetic resonance imaging (MRI) has a diagnos-tic accuracy approaching 70% to 95%, and a highnegative predictive value.

There are three tests that are frequently request-ed and that do not help much. The first is forserum uric acid. It could be normal in an acuteattack of gout, and elevated in people withoutgout, so this is not really helpful in diagnosinggout. The second and the third tests are for antinu-clear antibodies and rheumatoid factor. Both arepositive in approximately 5% of the normal popu-lation; so neither test is really useful without sup-port from the clinical scenario. Invasive tech-niques include arthroscopy, which is the gold stan-dard for the diagnosis of meniscal lesions, and isalso useful to get samples of synovial biopsies.6

In cases that involve arthritic knee, where, aftereight weeks and reasonable studies, no etiology hasbeen acquired, a synovial biopsy may be of help.

What are the treatment methods?

Methods of treatment for painful knees includeoral medications and injections (Table 2).

What is the role of physical therapy?

There is not a lot of support from evidence-basedmedicine for these approaches, nevertheless somepatients could find that:• ice may help in the acute phase after an injury

and could help after exercise. It is stated that icecauses vasoconstriction, and decreases meta-

bolic activity and blood flow. That will decreasethe inflammatory edema and the hemorrhage.Ice should be applied for no more than 20 min-utes at a time.10

• heat will increase their capillary blood flowand cellular permeability, and should be avoid-ed during the first 24 or 48 hours after an injury.After that, heat could be useful because it relax-es the muscle spasm. Superficial heat, as moisthot packs, should be applied for no more than20 minutes. For deep heating, ultrasound thera-py would be recommended.11 This is also effec-tive for inflammatory conditions.

• electrotherapy will help, as the transcutaneouselectrical nerve stimulation (TENS) is com-monly used for pain modulation.12 Its role isstill unclear.

• exercising the quadriceps (strengthening andflexibility exercises) should be recommended.11

It is stated that both aerobic and resistance exer-cises are beneficial to patients with arthritis.

• weight loss is another strategy. This appears toreduce the risk of developing OA of the knee,and improves the symptoms in those individu-als who already have the disease.

• being cautious, to avoid injuries, is important.13

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The Canadian Journal of CME / September 2003 149

Net Readings1. Aetna Intelihealth:

www.intelihealth.com

2. Hospital for Special Surgery:http://rheumatology.hss.edu/pat/specInfo/easeKneePain.asp

www.stacommunications.com

For an electronic version of this article, visit The Canadian Journal of CME online.

What about surgery?

A displaced meniscal tear that causes limitation ofrange of movement is an indication for surgery.Indications for total knee replacement shouldinclude pain refractory to treatment (especiallynocturnal pain).14

Our thanks to Dr. César A. Ugarte for providing the

pictures included in this manuscript

References1. Graham G, Fanclough J: The knee. In: Klippel and Dieppe

(ed): Rheumatology 2nd Edition. Mosby International,1998, pp 4.11.1–14

2. McAlindon TE. The knee. Best Pract Res Clin Rheumatol1999; 13(2):329-44.

3. Hawkins, RA. Approach to the patient with monoarticularsymptoms. In: West SG (ed): Rheumatology Secrets.Hanley & Belfus Inc. 1997, pp 74-9.

4. Fouquet B. Clinical examination as a tool for identifyingthe origin of musculoskeletal pain. Best Pract Res ClinRheumatol 2003; 17(1):1-16.

5. Emms NW, O´Connor M, Montgomery SC: Hip pathologycan masquerade as knee pain in adults. Age Ageing 2002;31(1):67-9.

6. Bellware D: Mechanical disorders of the knee. In: KoopmanWJ (ed): Arthritis and Allied Conditions. FourteenthEdition. Lippincott Williams and Wilkins 2001, pp 1988-95.

7. Kviev TK, Viktil K: Pharmacotherapy for regional muscu-loskeletal pain. Best Pract Res Clin Rheumatol 2003;17(1):137-50.

8. Towheed TE: Published meta-analyses of pharmacologicaltherapies for osteoarthritis. Osteoarthritis Cartilage 2002;10(11):836-7.

9. Hughes R, Carr A: A randomized, double blind, placebo-con-trolled trial of glucosamine sulphate as an analgesic inosteoarthritis of the knee. Rheumatology 2002; 41(3):279-84.

10. Taunton JE, Wilkinson M: Rheumatology: 14. Diagnosisand management of anterior knee pain. CMAJ 2001;164(11):1595-601.

11. Brander V, Chang RV: Rehabilitation for persons witharthritis and rheumatic conditions. In: Koopman WJ (ed):Arthritis and Allied Conditions 14 Edition. LippincottWilliams and Wilkins 2001, pp 943-64.

12. Ayral X: Injections in the treatment of osteoarthritis. BestPract Res Clin Rheumatol 2001; 15(4):609-26.

13. Hanada E: Efficacy of rehabilitative therapy in regionalmusculoskeletal conditions. Best Pract Res Clin Rheumatol2003; 17(1):151-66.

14. Cukcler JM: Surgical treatment of the knee. In: KoopmanWJ (ed): Arthritis and Allied Conditions 14 Edition.Lippincott Williams and Wilkins 2001, pp 1061-71.

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150 The Canadian Journal of CME / September 2003

Physical therapy may help painful knees:

• Ice: in the acute phase after an injuryand after exercise. Ice should be appliedfor no more than 20 minutes at a time.

• Heat: should be avoided during the first24 or 48 hours after an injury, but it canbe useful after that time, as it relaxes themuscle spasm. Heat should not beapplied for more than 20 minutes at atime.

• Exercise: can help the quadriceps(strengthening and flexibility exercises).

• Weight loss: appears to reduce the riskof developing osteoarthritis of the knee,and improves symptoms in individualswho already have the disease.

• Caution: should be taken to preventinjury.

Take-homemessage

CME