🔑 Key Learning

  • Common causes include overuse injuries, inflammation, or biomechanical issues

🦵 Patellofemoral Pain Syndrome (PFPS) 'Runners knee'

🧬 Pathophysiology

  • Overuse injury due to inflammation of the patellofemoral joint
  • Triggered by sudden increase in activity, muscle imbalance, prolonged kneeling

👀 Clinical Features

  • Achy knee pain, felt behind the patella
  • Worse with activity: walking, running, stairs, kneeling

🧪 Examination

  • Pain on patellar edge palpation
  • Anterior knee pain reproduced by squatting

💊 Management

  • Conservative: activity modification, physiotherapy, NSAIDs

🦴 Osgood-Schlatter’s Disease

🧬 Pathophysiology

  • Apophysitis at tibial tuberosity from traction stress during adolescence

👀 Clinical Features

  • Affects children aged 10–16, more common in boys
  • Pain over tibial tuberosity, worse after exercise/kneeling

🧪 Examination

  • Tender, possibly swollen tibial tuberosity
  • Pain with resisted knee extension
Male with Osgood Sch;atter. Note swelling over the tibial tuberosity. D3aj86, CC BY 3.0, via Wikimedia Commons

💊 Management

  • Rest, physiotherapy, NSAIDs

🧴 Prepatellar & Infrapatellar Bursitis

👀 Clinical Features

  • Swelling and pain over anterior knee
  • Prepatellar often post-trauma ('housemaid’s knee')
  • Infrapatellar linked to kneeling at work (e.g. tilers, plumbers)
Left knee prepatellar bursitis

🧪 Examination

  • Fluctuant anterior swelling
  • May have signs of infection (fever, erythema)

💊 Management

  • Aspiration if painful or ?infective
  • Consider flucloxacillin if signs of infection

🦵 Patellar Tendonitis 'Jumpers knee'

🧬 Pathophysiology

  • Overuse tendinopathy from jumping activities - MCQs may reference basketball etc. 
Injurymap, CC BY 4.0 , via Wikimedia Commons

👀 Clinical Features

  • Anterior knee pain, worse with running/jumping, especially downhill

🧪 Examination

  • Tenderness along patellar tendon
  • Pain with resisted knee extension

💊 Management

  • Relative rest, NSAIDs, physiotherapy

🦴 Osteochondritis Dissecans

🧬 Pathophysiology

  • Subchondral bone necrosis due to impaired blood supply
  • Dead fragments can detach into joint

👀 Clinical Features

  • Joint pain, locking or catching sensations

🧪 Investigations

  • X-ray: subchondral defects or loose bodies
Osteochondritis dissecans. Houghton, Kristin M (2007). "Review for the generalist: evaluation of anterior knee pain". Pediatric Rheumatology 5 (8). DOI:10.1186/1546-0096-5-8., CC BY 2.0, via Wikimedia Commons

       

🦵 Iliotibial Band Syndrome (ITBS)

🧬 Pathophysiology

  • Overuse friction injury between IT band and lateral femoral condyle
  • History of increased activity - e,g, running
IT band syndrome - lateral knee. PFPS (runners knee) behind patella. InjuryMap, CC BY-SA 4.0 , via Wikimedia Commons

👀 Clinical Features

  • Lateral knee pain, worsens with running or cycling
  • Pain just proximal to the joint line

💊 Management

  • Activity modification, ITB stretching, physiotherapy

💧 Baker’s Cyst

🧬 Pathophysiology

  • Popliteal bursa swelling, often secondary to OA or meniscal injury

👀 Clinical Features

  • Posterior knee swelling, can cause vague discomfort
  • Sudden rupture can mimic DVT: calf swelling, erythema, pain

🧪 Investigations

  • 1st line: Ultrasound to differentiate from DVT

💊 Management

  • Reassurance if asymptomatic
  • Treat underlying joint pathology

📝 Exam Clues & Clinchers

  • PFPS → anterior knee pain, behind patella, in runners, worse on stairs/kneeling
  • Osgood-Schlatter’s → adolescent with tibial tuberosity pain post-sport
  • Prepatellar bursitis → fluctuant anterior swelling, housemaid’s knee
  • Patellar tendonitis → jumper’s knee, pain worse with resisted extension
  • Osteochondritis dissecans → adolescent with knee locking/catching
  • ITBS → lateral knee pain in runner, worse with flexion/extension
  • Baker’s cyst → bulge in popliteal fossa

🔗 Useful Links and References