Patellofemoral Pain Syndrome

This article is a stub.

Patellofemoral Pain Syndrome
Synonym	Runner's knee, retropatellar pain syndrome, lateral facet compression syndrome, idiopathic anterior knee pain. Also chondromalacia patella where there are changes to the patella articular cartilage.
Definition	Anterior knee pain where other causes have been excluded.
Epidemiology	Very common. More common in women.

Patellofemoral pain is anterior knee pain involving the patella and retinaculum where other causes of anterior knee pain have been excluded.

Clinical Features

Red Flags

• Fracture or tendon and ligament rupture, osteonecrosis: Major trauma, Sudden onset of pain, Minor trauma with risk factors (age over 50, history of osteoporosis, corticosteroid use)
• Infection, crystal arthritis: fever, night sweats, signs of inflammation, risk factors for infection (underlying disease process, immunosuppression, penetrating wound)
• Tumour: past history of malignancy, age >50, failure to improve, weight loss, pain at multiple sites, rest pain, night pain

Differential Diagnosis

Differential Diagnosis

Differential Diagnoses

Anterior, focal or vague

• Patellofemoral Pain Syndrome
• Knee Osteoarthritis
• Patellar Tendinopathy
• Plica Syndrome
• Quadriceps Tendinopathy
• Patellar Instability
• Hoffa's Fat Pad Inflammation
• Prepatellar Bursitis and Infrapatellar Bursitis
• Osgood-Schlatter Disease
• Sinding-Larsen-Johansson Disease
• Referred hip pain
• Avascular necrosis
• Patellar Stress Fractures
• Anterior cruciate ligament tear
• Osteochondral defect
• Posterior cruciate ligament tear
• Tibiofemoral dislocation
• Parameniscal cyst

Medial

• Knee Osteoarthritis
• Medial collateral ligament tear
• Medial meniscal tear
• Medial meniscal cyst
• Bakers cyst
• Medial Plica Syndrome
• Pes anserine bursitis/tendinopathy
• Inflammatory arthritis
• Osteochondral lesion medial femoral condyle (lateral aspect of medial epicondyle most common)
• Saphenous Nerve Entrapment
• Medial friction syndrome
• Medial collateral ligament bursitis
• Osteonecrosis
• Semimembranosus-Tibial Collateral Ligament Bursitis
• Pigmented Villonodular Synovitis
• Synovial Chondromatosis
• Referred Pain - Hip Joint, Lumbosacral spine pathology
• Neoplasm - soft tissue, intraosseous

Lateral

• Lateral meniscus tear
• Posterolateral corner injury
• Patellar dislocation or subluxation
• Lateral collateral ligament tear
• Iliotibial Band Syndrome
• Osteoarthritis exacerbation
• Osteochondral lesion lateral femoral condyle
• Popliteus Tendinopathy
• Biceps Femoris Tendinoapthy
• Semimembranosus Tendinopathy/bursitis
• Fibula head fracture
• Proximal Tibiofibular Joint Instability
• Snapping Biceps Femoris and Popliteus Tendons
• Peroneal Nerve Compression/Neuritis

Posterior

• Baker's or popliteal cyst
• Popliteus Tendinopathy
• Popliteal artery aneurysm
• Popliteal artery entrapment
• Posterior capsule tear
• Posterior cruciate ligament tear
• Tibiofemoral dislocation

Effusion present without trauma

• Osteochondral injury
• Osteoarthritis exacerbation
• Rheumatological disease (gout, RA, psoriatic arthritis)
• Septic arthritis

Treatment

In the acute phase overload is very likely. Runners should reduce their running volume, and in severe cases should stop running entirely. Those with more mild symptoms may only need to reduce more strenuous activities such as hill running. In order to maintain fitness runners can be encouraged to use a stationary bike, upper body cycle, swimming, or other activities that do not cause knee pain.

Hip and knee strengthening is more effective than knee strengthening alone.

There is limited evidence for the use of NSAIDs in the short term, with naproxen being more effective than placebo.

There is no evidence to support the use of ultrasound, iontophoresis, phonophoresis, or electrical stimulation.

Resources

Hip and Knee Strengthening in Patellofemoral Syndrome Metaanalysis - Nascimiento 2018.pdf - 477 KB (f)

Literature Review

Literature Review

Reviews from the last 7 years: review articles, free review articles, systematic reviews, meta-analyses, NCBI Bookshelf

Articles from all years: PubMed search, Google Scholar search.

TRIP Database: clinical publications about evidence-based medicine.

Other Wikis: Radiopaedia, Wikipedia Search, Wikipedia I Feel Lucky, Orthobullets,