Knee pain resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Tayyaba Ali, M.D.[2]

Synonyms and keywords: Knee stiffness, Knee swelling, Hot knee joint

Causes

Traumatic and activity-related causes of knee pain

Anterior Knee Pain
Patellar subluxation or dislocation Tibial apophysitis (Osgood-Schlatter lesion) Jumper's knee (patellar tendonitis) Patellofemoral pain syndrome (chondromalacia patellae)
Medial Knee Pain
Medial collateral ligament sprain Medial meniscal tear Pes anserine bursitis Medial plica syndrome
Lateral Knee Pain
Lateral collateral ligament sprain Lateral meniscal tear Iliotibial band tendonitis
Posterior Knee Pain
A popliteal cyst (Baker's cyst) as a result of sport-related injury Posterior cruciate ligament injury

Non-Traumatic causes of knee pain

Unilateral Knee Pain
Septic Arthritis Gout Pseudogout (acute calcium pyrophosphate crystal arthritis)
Bilateral Knee Pain
Osteoarthritis Rheumatoid Arthritis Systemic Lupus Erythematosis Baker cyst as a result of Rheumatoid arthritis and Osteoarthritis

Diagnosis

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Seek proper history: Onset of knee pain Have you noticed: ❑ Warmth of joint ❑ Redness of joint ❑ Stiffness of joint ❑ Swelling of joint ❑ Weakness of joint ❑ Numbness or tingling of joint ❑ Discoloration of fingers in the cold ❑ Discomfort on exposure to sunlight ❑ Pain in any other joint

Examine the patient: ❑ HEENT signs: Conjunctival pallor Jaundice ❑ Inspection: Skin changes Color changes Physical abnormality Swelling Scar marks ❑ Palpation: Look for pain on palpation ❑ Range of motion: Perform extension and flexion of both knee joints ❑ Power Check power on flexion and extension ❑ Perform knee maneuvers for examination of knee ligament injuries Medial collateral ligament/Lateral collateral ligament injury: Valgus stress test Varus stress test Anterior collateral ligament injury: Anterior drawer test Lachman test Posterior collateral ligament injury: Posterior drawer test Posterior sag test Meniscal tear: Thessaly test Apley test McMurray test

Initial workup for knee pain: ❑ Complete blood count (CBC) with differential ❑ Erythrocyte sedimentation rate (ESR) ❑ Arthrocentesis and analysis ❑ X-ray knee anteroposterior (AP) view and lateral view ❑ CT scan knee MRI knee DEXA scan Ca++ and Vitamin-D levels

Knee pain associated with trauma

Knee pain not associated with trauma

Significant knee swelling ❑ Anterior cruciate ligament (ACL) tear ❑ Large meniscus tear ❑ Intra-articular fracture ❑ Osteochondral defect ❑ Patellar dislocation ❑ Posterior lateral corner tear ❑ Posterior cruciate ligament (PCL) tear ❑ Patellar tendon tear ❑ Quadriceps tendon tear ❑ Knee (tibiofemoral) dislocation

Limited knee swelling ❑ Small or moderate meniscus tear ❑ Medial collateral ligament (MCL) strain ❑ Lateral collateral ligament (LCL) strain ❑ Patellar subluxation ❑ Partial ACL tear ❑ Partial PCL tear ❑ Patella fracture ❑ Fibular neck or head fracture

Knee joint effusion present

Knee joint effusion absent

Activity related knee pain ❑ Chronic osteochondral defect ❑ Knee osteoarthritis

Not activity related knee pain ❑ Crystal arthropathy ❑ Septic arthritis ❑ Systemic rheumatic disease

According to the focus of knee pain

Anterior knee pain ❑ Tibial tubercle apophysitis (Osgood Schlatter) ❑ Hoffa's fat pad syndrome ❑ Quadriceps and patellar tendinopathy ❑ Prepatellar or infrapatellar bursitis ❑ Plica syndrome

Vague anterior knee pain ❑ Chronic patella dislocation or subluxation ❑ Patellofemoral pain ❑ Chondromalacia patella ❑ Patella stress fracture

Medial knee pain ❑ Degenerative medial meniscal tear ❑ Saphenous nerve entrapment ❑ Pes anserine bursitis

Lateral knee pain ❑ Iliotibial band syndrome ❑ Degenerative lateral meniscal tear

Posterior knee pain ❑ Popliteal artery aneurysm ❑ Popliteal artery entrapment ❑ Popliteal (Baker's) cyst ❑ Popliteus tendinopathy

Treatment

Shown below is an algorithm summarizing the treatment of [[disease name]] according the the [...] guidelines.

Do's

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Don'ts

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