Pes anserine bursitisMANAGEMENT

THIGH & KNEE · 12 SECTIONS

⚲

356 items

☷ Legend

01Approach to the Critical Patient/attcp24

Triage and red flags

›Immediate risk screen

›Fever

›Rapidly progressive erythema

›Systemic toxicity

›Immunocompromised state

›Severe pain out of proportion

›Inability to bear weight

›Acute locked knee

›Hot swollen knee with large effusion

›Recent penetrating trauma or injection at site

›If septic arthritis concern, immediate ED level evaluation

›If necrotizing soft tissue infection concern, immediate surgical consult

Key concepts

›Working diagnosis frame

›Medial proximal tibial pain

›Pain at pes anserinus insertion region

›Overuse and biomechanical contributors

›Common co-morbidity with knee osteoarthritis

›Infection uncommon but high consequence

Monitoring targets

›Reassessment checkpoints

›Pain trend after initial analgesia

›Weight bearing ability trend

›Skin temperature and erythema trend

›Range of motion limitation trend

›If worsening despite conservative plan, diagnostic reassessment

02History/hx37

Symptom pattern

›Pain features

›Medial knee pain location

›Proximal medial tibial point tenderness

›Activity related flare

›Stair climbing related flare

›Rising from chair related flare

›Night pain

›Mechanical symptoms

›Instability symptoms

Timeline and triggers

›Temporal context

›Acute overuse change

›New running or walking volume

›New hills or stairs exposure

›New footwear

›Recent knee injury

›Recent knee surgery

Risk factors and comorbidities

›Predisposition

›Knee osteoarthritis symptoms

›Obesity

›Diabetes mellitus

›Pes planus

›Valgus knee alignment symptoms

›Hamstring tightness symptoms

›Prior medial knee pathology

Infection risk history

›Infectious clues

›Fever or chills

›Skin break near site

›Cellulitis history

›Immunosuppression

›Recent injection

›MRSA risk factors

Medication context

›Medication factors

›Anticoagulants

›Antiplatelets

›NSAID contraindications

›Steroid injection glucose sensitivity

›Allergy history

03Physical Exam/exam30

Focused knee and pes region

›Local findings

›Point tenderness at anteromedial proximal tibia

›Local swelling over pes region

›Warmth or erythema

›Pain with resisted knee flexion

›Pain with resisted hip adduction

›Hamstring tightness

Knee joint assessment

›Joint evaluation

›Effusion presence

›Active range of motion

›Passive range of motion

›Pain with terminal flexion

›Medial joint line tenderness

›Patellofemoral pain provocation

Stability and meniscus screen

›Co-injury screen

›Valgus stress pain or laxity

›Varus stress pain or laxity

›Anterior drawer or Lachman laxity

›McMurray pain or click

›Thessaly pain

Neurovascular and skin

›Distal status

›Distal pulses

›Distal sensation

›Skin integrity near tenderness region

›If cellulitis signs, margin tracking for progression

PITFALLS

›Common misses

›Medial meniscus tear mistaken for bursitis

›Medial tibial stress injury mistaken for bursitis

›Septic arthritis mistaken for bursitis when large effusion present

›Referred pain from hip in older adults

04Differential Diagnosis/ddx24

Medial knee pain differential

›Common mimics

›Medial meniscus tear

›Medial collateral ligament sprain

›Knee osteoarthritis flare

›Patellofemoral pain syndrome

›Semimembranosus tendinopathy

›Hamstring tendinopathy

›Medial plica syndrome

High risk alternatives

›Dangerous alternatives

›Septic arthritis

›Septic bursitis

›Osteomyelitis

›Necrotizing soft tissue infection

›Deep vein thrombosis with atypical presentation

Imaging driven alternatives

›Structural alternatives

›Medial tibial plateau fracture

›Medial tibial stress fracture

›Osteochondral lesion

›Meniscal root tear

Coding aligned problem list

›ICD-10 and SNOMED mapping

›Pes anserinus bursitis SNOMED CT 73105000

›Other bursitis of knee ICD-10-CM M70.5 category

›Right knee bursitis ICD-10-CM M70.51

›Left knee bursitis ICD-10-CM M70.52

05Laboratory Tests/lt33

When infection or systemic disease possible

›Infection workup triggers

›Fever

›Marked warmth and erythema

›Rapid progression

›Immunocompromised state

›Large effusion with limited range of motion

›Severe pain and inability to bear weight

›Post injection worsening

›If septic arthritis concern, joint aspiration prioritized over serum markers

Serum tests

›Supportive labs

›Complete blood count for systemic infection concern

›Leukocytosis supportive but non diagnostic

›Normal count does not exclude infection

›C reactive protein for inflammatory or infectious concern

›Trend helpful for response

›Single value limited specificity

›Erythrocyte sedimentation rate for inflammatory or infectious concern

›Slow kinetics

›Limited specificity

›Serum glucose for diabetes and steroid injection planning

›Hyperglycemia risk counseling after injection

Fluid studies when aspirated

›Aspiration analysis

›Gram stain

›Limited sensitivity

›Positive supports infection

›Culture and sensitivity

›Highest yield for targeted therapy

›Prior antibiotics reduce yield

›Cell count with differential

›High neutrophils support infection

›Overlap with inflammatory states

›Crystal analysis when gout or CPPD possible

›Coexistence with infection possible

06Diagnostic Tests/dt40

Scoring Systems

›Decision aids and symptom scales

›Ottawa Knee Rule for radiograph decision after acute injury

›Age 55 years or older

›Isolated patellar tenderness

›Fibular head tenderness

›Inability to flex to 90 degrees

›Inability to bear weight 4 steps

›Patient reported outcome tools for follow up

›KOOS for knee function tracking

›WOMAC for osteoarthritis symptom tracking

Radiographs

›Plain film role

›Normal in isolated bursitis typical

›Osteoarthritis severity assessment

›Fracture exclusion after trauma mechanism

›Standard views when indicated

›AP

›Lateral

›Sunrise or merchant for patellofemoral symptoms

›Weight bearing views for osteoarthritis assessment

MRI

›MRI indications

›Persistent pain despite appropriate conservative care

›Mechanical symptoms

›Suspected meniscal tear

›Suspected stress fracture when radiographs negative

›Suspected occult tibial plateau fracture

›Suspected tendon tear

›Suspected osteochondral lesion

›MRI interpretation pearls

›Pes bursa fluid signal may be present

›Concomitant degenerative changes common

›CT indications

›Tibial plateau fracture characterization when suspected

›Preoperative planning when fracture confirmed

›Limited role for isolated bursitis

Ultrasound

›Point of care and diagnostic ultrasound

›Bursa fluid distension evaluation

›Guidance for aspiration or injection

›Cellulitis versus fluid collection differentiation

›Doppler evaluation for hyperemia supportive of inflammation

›DVT ultrasound if clinical suspicion for calf swelling and risk factors

07Disposition/dispo17

Outpatient management

›Discharge appropriate

›Stable vitals

›No systemic infection features

›No large effusion with severe range limitation

›Pain controlled with oral plan

›Ambulation feasible with or without aid

›Clear follow up plan

Referral and follow up timing

›Follow up targets

›Primary care or sports medicine in 1 to 2 weeks if persistent symptoms

›Physical therapy referral early when biomechanical contributors present

›Orthopedics referral if refractory or structural pathology suspected

Escalation and admission criteria

›Higher level care triggers

›Septic arthritis concern

›Rapidly progressive cellulitis

›Immunocompromised with systemic symptoms

›Inability to bear weight with concerning exam

›Suspected fracture despite negative radiographs

08Treatment/t83

Immediate life-saving interventions

›Infection and sepsis pathways

›If septic arthritis concern, emergent joint aspiration and orthopedic consult

›If unstable or septic, IV antibiotics after cultures

›If stable, antibiotics after aspiration when feasible

›If necrotizing infection concern, immediate surgical consult and broad spectrum antibiotics

Immobilization and Splinting

›Activity modification supports

›Relative rest from provoking activity

›Temporary reduction of stairs and hills

›Short term cane on contralateral side for painful gait

›Knee sleeve for comfort if helpful

Reduction

›Not applicable for isolated bursitis

›If mechanical locking or instability, alternate diagnosis pathway

›If acute trauma deformity, fracture or dislocation pathway

Open fracture medications and timing

›Not applicable for isolated bursitis

›If open wound near knee after trauma, open injury pathway

DVT prophylaxis when relevant

›Not routinely indicated

›If prolonged immobility from pain, individual risk assessment

›If suspected DVT, diagnostic pathway rather than prophylaxis

Conservative care

›First line measures

›Ice packs 10 to 15 minutes

›Up to 3 to 5 times daily

›Skin barrier to prevent frost injury

›Compression as tolerated

›Avoid excessive tightness

›Stop if paresthesia or color change

›Elevation when swollen

›Above heart level when feasible

›Short frequent sessions

›Topical NSAID option

›Diclofenac 1 percent gel

›2 g to knee region up to 4 times daily

›Oral NSAID options when no contraindication

›Ibuprofen 400 mg every 6 to 8 hours as needed

›Naproxen 250 to 500 mg twice daily as needed

›Avoid duplicate NSAIDs

›Acetaminophen options

›500 to 1000 mg every 6 to 8 hours as needed

›Maximum daily limit per local policy and liver risk

Physical therapy and biomechanics

›Rehab focus

›Hamstring stretching program

›Quadriceps strengthening

›Hip abductor strengthening

›Core stabilization

›Gait retraining if valgus collapse

›Gradual return to run or walk program

›Mechanical contributors

›Foot orthoses for pes planus symptoms

›Shoe assessment and replacement if worn

›Weight management counseling when appropriate

Injection and procedures

›Indications for injection

›Persistent pain despite conservative therapy

›Functional limitation despite rehab

›Localized tenderness with supportive ultrasound findings

›Corticosteroid injection principles

›Ultrasound guidance preferred when available

›Avoid injection through cellulitis

›Avoid if bacteremia concern

›Limit repeat injections

›Minimum 3 months between injections

›Typical maximum 3 to 4 per year per site

›Example injection regimen

›Triamcinolone acetonide 20 to 40 mg

›With lidocaine 1 percent 1 to 2 mL

›Total volume tailored to anatomy

›Post injection rest 24 to 48 hours

›Post injection counseling

›Post injection flare 24 to 72 hours possible

›Skin atrophy or hypopigmentation risk

›Infection risk low but present

›Transient hyperglycemia risk in diabetes

Antibiotics when septic bursitis suspected

›Outpatient oral options when stable and no joint involvement

›Cephalexin 500 mg four times daily

›Typical duration 7 to 10 days

›Adjust for renal function

›If MRSA risk, trimethoprim sulfamethoxazole DS 1 tablet twice daily

›Combine with beta lactam if streptococcal coverage needed

›If beta lactam allergy, clindamycin 300 to 450 mg three times daily

›C difficile risk counseling

›IV antibiotics and admission triggers

›Systemic toxicity

›Immunocompromised state

›Failure of oral therapy

›Concern for septic arthritis or deep infection

09Special Populations/sp20

Pregnancy

›Pregnancy considerations

›Prefer non pharmacologic measures first

›Acetaminophen preferred analgesic when needed

›NSAID avoidance in later pregnancy

›Injection risk benefit individualized

›Ultrasound favored imaging modality

Geriatric

›Older adult considerations

›High prevalence coexisting osteoarthritis

›Lower threshold for radiographs after trauma

›NSAID renal and GI risk

›Fall risk with painful gait

›Assistive device planning

Pediatrics

›Pediatric considerations

›Less common diagnosis than in adults

›Growth plate injury as alternative diagnosis after trauma

›Septic arthritis vigilance with fever and refusal to bear weight

›Weight based analgesic dosing

›Ibuprofen 10 mg per kg per dose every 6 to 8 hours

›Maximum single dose per local policy

›Acetaminophen 15 mg per kg per dose every 4 to 6 hours

10Background/b19

Epidemiology

›Epidemiology essentials

›Common cause of medial knee pain syndrome in adults

›Association with obesity and knee osteoarthritis

›Association with overuse and biomechanical stress

Pathophysiology

›Mechanism

›Bursa inflammation between pes tendons and medial tibia

›Microtrauma from repetitive friction

›Contributing tendinopathy common

›Adjacent osteoarthritis increases local stress and pain sensitization

Therapeutic Considerations

›Treatment rationale

›Load reduction decreases friction and inflammation

›Stretching reduces pes tendon tension

›Strengthening improves knee and hip mechanics

›Topical NSAIDs reduce local inflammation with lower systemic risk

›Steroid injection for refractory cases to reduce inflammatory cascade

›Evidence framing

›Conservative care as first line standard

›Corticosteroid injection effective for short term pain relief in some studies

›Long term outcomes linked to addressing biomechanics and comorbid OA

11Patient Discharge Instructions/pdi20

copy discharge instructions

›Home plan

›Relative rest from stairs hills squats and running

›Ice 10 to 15 minutes up to 3 to 5 times daily

›Topical diclofenac option if safe

›Oral ibuprofen or naproxen option if safe

›Acetaminophen option if needed

›Gentle hamstring stretching daily

›Gradual return to activity only when improving

›Follow up

›Primary care or sports medicine in 1 to 2 weeks if not improving

›Physical therapy referral for strengthening and stretching program

›Imaging discussion if persistent pain beyond 4 to 6 weeks

›Return now or urgent reassessment

›Fever

›Rapidly spreading redness

›Hot swollen knee with severe motion pain

›Inability to bear weight

›New numbness or foot weakness

›New calf swelling or shortness of breath

›Worsening pain despite rest and medication

12References/r9

Clinical summaries and reviews

›Reference set

›StatPearls Pes Anserine Bursitis updated 2024

›Gouda et al comparative efficacy corticosteroid injection versus PRP versus ESWT 2023

›AJR review local and systemic side effects of corticosteroid injections 2024

›MedlinePlus steroid injections risks updated 2024

Coding and terminology

›Coding references

›ICD-10-CM M70.51 other bursitis of knee right knee

›ICD-10-CM M70.52 other bursitis of knee left knee

›SNOMED CT 73105000 pes anserinus bursitis

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed March 6, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.