Causes of Pain on the Medial Side of the Knee

1. Pes Anserinus Syndrome (Anserine Bursitis / Tendinopathy)

• Who gets it: Overweight, middle-aged to elderly women with osteoarthritis of the knee
• Symptoms: Pain and tenderness over the medial knee, about 2 inches (5 cm) below the joint line. Pain is worse climbing stairs
• Why it's missed: It frequently co-exists with knee osteoarthritis, so the OA gets blamed for all the pain

"Pes anserinus syndrome is often overlooked because it frequently occurs concomitantly with osteoarthritis of the knee...in some cases of dual involvement, pes anserinus syndrome may be the principal source of the pain." - Goldman-Cecil Medicine

2. Medial Collateral Ligament (MCL) Sprain / Injury

• Mechanism: Forceful valgus loading - e.g., a lateral blow to the knee (common in contact sports), or a twisting fall
• Symptoms: Pain and tenderness directly over the MCL, medial joint line swelling, pain on applying valgus stress to the knee
• Diagnosis: Tenderness on palpation + valgus stress test; MRI for grading

3. Medial Meniscus Tear

• Symptoms: Medial joint line tenderness, pain with twisting/rotation, swelling, episodic locking or giving way of the knee
• Classic sign: McMurray's test - pain or a click on the medial joint line when the knee is rotated while flexed
• Locking: Particularly with bucket-handle tears, where the torn fragment can flip into the joint
• Source: As Campbell's Operative Orthopaedics (2026) notes: "A torn meniscus usually causes periodic episodes of giving way, buckling, locking, and pain localized along the joint line, and pain often is increased or reproduced by torsion of the flexed knee"

4. Medial Knee Osteoarthritis

• Who gets it: Middle-aged to elderly adults; more common with obesity, prior injury, varus (bow-legged) deformity
• Symptoms: Deep aching medial knee pain, stiffness after rest, crepitus, joint-line tenderness, progressive deformity
• X-ray findings: Medial joint space narrowing, subchondral sclerosis, osteophytes

5. Medial Plica Syndrome

• Type: The medial patellar plica is the most clinically significant
• Symptoms: Anteromedial knee pain, a snapping or clicking sensation as the plica rolls over the medial femoral condyle during knee flexion, a palpable tender band on the medial side
• Tintinalli's Emergency Medicine describes it as: "snapping sensation and sound may be accompanied by pain in the location passing over the medial condyle with the initiation of flexion and termination of extension"
• Diagnosis: Often made on MRI or arthroscopy; easy to miss

6. Medial (Tibial Collateral Ligament) Bursitis

• Causes: Repetitive stress, direct trauma, inflammatory arthritis (e.g., rheumatoid arthritis, gout)
• Bursitis here can mimic MCL injury or pes anserine syndrome

7. Referred Pain / Other Causes

• Baker's (popliteal) cyst - fluid-filled swelling behind the knee (medial side), caused by any effusion. If it ruptures, it can cause calf pain mimicking DVT
• Medial tibial stress syndrome (shin splints) - in runners, pain along the medial tibial border
• Referred pain from the hip - hip OA can refer pain to the medial knee (same nerve distribution via obturator nerve)
• Gout / pseudogout - crystal arthritis can cause acute medial joint pain
• Saphenous nerve entrapment - the saphenous nerve runs along the medial knee and can be compressed, causing medial knee and leg pain

Summary Table

Posterior Head Pain (Occipital / Back-of-Head Pain)

1. Occipital Neuralgia

• Sudden-onset stabbing, electric shock-like, or sharp shooting pain starting in the nuchal (neck) region, rapidly spreading toward the top of the head (vertex)
• Usually unilateral
• Paroxysms can be triggered by brushing the hair, touching the scalp, or moving the neck
• Between attacks, a dull background aching may persist
• Tenderness or hypersensitivity in the occipital scalp on examination

• Chronic neck tension or muscle spasm (most common)
• Osteoarthritis or degenerative disease of upper cervical spine (C2-C3)
• Whiplash injury or trauma to the back of the head
• Entrapment of the greater occipital nerve as it pierces the trapezius and semispinalis capitis muscles at their tendinous attachments
• Rarely: tumors, arteriovenous malformations

2. Tension-Type Headache (TTH)

• Mild to moderate, pressing or tightening (non-pulsating) quality
• Holocranial (whole head) but often felt most at the occiput and back of neck
• No nausea/vomiting; may have photophobia OR phonophobia (not both)
• Does NOT worsen with physical activity (unlike migraine)
• More common in women; associated with stress, poor posture, eye strain, fatigue

• Acute: Acetaminophen (650-1000 mg) or NSAIDs (ibuprofen 200-800 mg, naproxen 250-500 mg, aspirin 250-1000 mg)
• Chronic prevention: Amitriptyline (10-100 mg at bedtime) - the only proven prophylactic; also nortriptyline, physical therapy, relaxation techniques
• Note: Triptans do NOT help pure tension headache - Goldman-Cecil Medicine; Harrison's Principles, 22nd Ed

3. Cervicogenic Headache

• Pain localized to the occipital area, but may radiate to frontal, temporal, or orbital regions
• Triggered or worsened by neck movement or sustained neck postures
• Constant background pain with episodic flares
• Tenderness over the greater/lesser occipital nerve, cervical facet joints, and upper neck muscles
• History of head/neck trauma is common

4. "Third Occipital Nerve" Headache

• Unilateral occipital and suboccipital ache
• Prevalence of ~27% after whiplash injuries
• Confirmed by percutaneous fluoroscopic nerve block; treated with radiofrequency coagulation or steroid injection - Adams and Victor's Neurology

5. Migraine

• Associated with nausea/vomiting, photophobia AND phonophobia, worsened by activity
• May be preceded by aura (visual disturbances, sensory symptoms)
• Posterior/basilar migraine can cause occipital pain, vertigo, diplopia, ataxia

6. Hypertensive Headache

• Felt in the occiput, often on waking in the morning
• Described as pounding or throbbing
• Should always be considered when posterior head pain is new or severe

7. Serious / Dangerous Causes (Red Flags)

Red Flag Signs - When to Seek Urgent Care

• Sudden and "thunderclap" (worst ever headache)
• Associated with fever, neck stiffness, or photophobia
• Associated with visual changes, double vision, or weakness
• In someone over 50 with new-onset headache
• Worsening progressively over days/weeks
• Following head or neck trauma

Summary