01Approach to the Critical Patient/attcp44

Alarm features and urgent escalation

›Red flag findings requiring immediate action

›Locked knee (inability to fully extend)

›Suggests displaced bucket-handle meniscal tear

›Prompt orthopedic surgical referral same day

›Rapid hemarthrosis within 1-2 hours of injury

›More consistent with ACL rupture, patellar dislocation, or tibial plateau fracture than isolated meniscal tear

›Urgent imaging and orthopedic consultation

›Neurovascular deficit distal to knee

›Concern for knee dislocation with popliteal artery injury

›Emergent vascular surgery consultation

›Inability to straight leg raise

›Extensor mechanism disruption until proven otherwise

›Patellar or quadriceps tendon rupture must be excluded

›Fever with severe pain and restricted passive ROM

›Septic arthritis until proven otherwise

›Emergent joint aspiration required

Key clinical decision points

›Severity stratification

›Nondisplaced tear with preserved ROM

›Conservative management pathway

›Weight-bearing as tolerated with analgesia

›Displaced or bucket-handle tear

›Surgical referral same day or next day

›Knee immobilizer and non-weight-bearing pending consultation

›Concomitant ACL tear

›Significantly changes surgical planning

›Meniscal repair success rates higher when combined with ACL reconstruction

02History/hx55

Mechanism and onset

›Mechanism of injury

›Noncontact twisting or rotatory injury

›Classic mechanism for traumatic meniscal tear

›Pivoting, squatting, or deceleration common precipitants

›Direct contact or blow to the knee

›Less typical for isolated meniscal tear; raises fracture concern

›Insidious onset without clear mechanism

›Degenerative meniscal tear more likely, especially in patients over 45

Symptom characterization

›Pain features

›Location: focal medial or lateral joint line

›Medial joint line suggests medial meniscus

›Lateral joint line suggests lateral meniscus

›Audible or sensory pop at time of injury

›May or may not be reported; not pathognomonic

›Pain with deep squatting, pivoting, or stair climbing

›Swelling and effusion

›Onset typically over hours (not immediate)

›Rapid onset effusion within 1-2 hours more suggestive of hemarthrosis from ACL, fracture, or patellar dislocation

›Degree and progression of swelling

›Mechanical symptoms

›Clicking, catching, or clunking

›Sensitivity 0.32-0.69; specificity 0.45-0.74 for meniscal tear

›Locking or inability to fully straighten knee

›Suggests displaced tear causing mechanical block

›Giving way

›On flat ground suggests ligamentous instability rather than meniscal tear alone

03Physical Exam/exam51

Inspection and general assessment

›Inspection findings

›Effusion

›Typically develops over hours; smaller than ACL-associated hemarthrosis

›Ecchymosis

›Deformity or malalignment

›Antalgic gait or inability to bear weight

Palpation

›Joint line tenderness

›Most sensitive single clinical finding for meniscal tear

›Sensitivity 83%, specificity 83%

›Medial joint line for medial meniscus

›Lateral joint line for lateral meniscus

›Distinguish from ligament tenderness (above or below joint line)

Range of motion

›ROM assessment

›Terminal flexion pain

›Common with posterior horn tears

›Extension deficit or mechanical block

›Lack of full extension strongly suggests displaced bucket-handle tear

›Symmetric comparison with contralateral knee

Provocative maneuvers

›McMurray test

›Sensitivity 61%, specificity 84%

›Most balanced overall performance for meniscal tear (JAMA 2001)

›Medial meniscus: external rotation with valgus stress

›Lateral meniscus: internal rotation with varus stress

›Positive: audible or palpable click with pain at joint line

04Differential Diagnosis/ddx42

Ligamentous injuries

›ACL tear (S83.511)

›Rapid hemarthrosis within 1-2 hours

›Positive Lachman and anterior drawer tests

›Pivoting instability on flat ground

›Often coexists with meniscal tear

›MCL sprain (S83.421)

›Medial pain with direct blow or valgus mechanism

›Tenderness over ligament body, not joint line

›Positive valgus stress test

›LCL or posterolateral corner injury (S83.431)

›Lateral pain, varus mechanism

›Positive varus stress test

Bony injuries

›Tibial plateau fracture (S82.101)

›High-energy mechanism

›Inability to bear weight

›Lipohemarthrosis on lateral radiograph

›Ottawa Knee Rules help screen for fracture

›Osteochondral fracture or loose body (S83.30)

›Locking and catching with effusion

›May coexist with patellar dislocation

Patellofemoral pathology

›Patellar dislocation or subluxation (S83.001)

›Anterior knee pain

›Positive apprehension test

›Effusion with lateral patellar tenderness

›Associated with rapid effusion from osteochondral injury

05Laboratory Tests/lt27

Routine labs

›Standard labs not indicated for isolated traumatic meniscal tear

›No routine blood work required if clinical picture is clear

›CBC and BMP if surgical intervention is anticipated preoperatively

Synovial fluid analysis

›Joint aspiration indications

›Suspected septic arthritis

›Fever, erythema, severe pain with passive ROM

›Large tense effusion causing significant pain

›Aspiration provides diagnostic information and symptomatic relief

›Synovial fluid interpretation

›WBC count

›Under 2,000 per microlitre: normal or traumatic

›2,000-50,000 per microlitre: inflammatory

›Over 50,000 per microlitre with PMN predominance: septic arthritis until proven otherwise

›Gram stain and culture

›Sensitivity approximately 60-80% for septic arthritis

›Crystal analysis

›Urate crystals: gout

›Calcium pyrophosphate crystals: pseudogout

›Bloody or serosanguineous fluid

›Hemarthrosis suggests ACL tear, fracture, osteochondral injury, or patellar dislocation rather than isolated meniscal tear

Inflammatory markers

›Inflammatory workup indications

›Suspected inflammatory arthritis

›ESR and CRP

›Rheumatoid factor and anti-CCP

›Uric acid

06Diagnostic Tests/dt67

Scoring Systems

›Ottawa Knee Rules

›Validated clinical decision rule to determine need for radiography

›Age 55 or older

›Fibular head tenderness

›Isolated patellar tenderness without other bony tenderness

›Inability to flex knee to 90 degrees

›Inability to bear weight immediately and in ED (4 steps)

›Sensitivity 99% for fracture (pooled meta-analysis, 7,385 patients)

›Negative result reliably excludes clinically significant fracture

›Specificity approximately 49%

›Radiographs not required if none of the 5 criteria are met

›AAOS Acute Isolated Meniscal Pathology CPG 2024

›Combination of clinical examination tests recommended over single test

›McMurray plus Apley plus joint line tenderness provides best accuracy

›Physical therapy recommended as first-line for nonobstructive tears

›AAOS Strong Recommendation based on Level I evidence

›MRI recommended when diagnosis uncertain or surgery being considered

›AAOS Moderate Recommendation

MRI

›MRI indications for acute knee injury

›Diagnosis uncertain after clinical assessment

›MRI sensitivity 78-89%, specificity 88-95% for meniscal tears versus arthroscopy

›Symptoms persist despite 4-6 weeks of conservative management

›Preoperative planning for suspected reparable tear or multi-ligament injury

›Suspected concomitant ACL tear or chondral injury

›MRI findings in meniscal tears

›Grade I: focal signal increase within meniscus not reaching surface

›Intrasubstance degeneration; no treatment required

›Grade II: linear signal not reaching articular surface

›Degenerative change; rarely symptomatic

›Grade III: signal extending to articular surface

›True tear; correlates with arthroscopic findings

›Bucket-handle tear pattern

›Double PCL sign on sagittal view

›Displaced fragment seen in intercondylar notch

›Limitations of MRI

›Not required for first-line assessment, especially in middle-aged and older adults

›Asymptomatic tears common on MRI in adults over 45

›MRI findings must be correlated with clinical presentation

›Knee effusion over 10 mm on lateral radiograph in patients under 40 should prompt MRI consideration (ACR Appropriateness Criteria 2020)

›MRI protocol

›Standard knee MRI without contrast in most cases

›MR arthrography may increase accuracy for recurrent or post-surgical tears

›3 Tesla preferred over 1.5 Tesla for improved resolution

CT

›CT indications for acute knee injury

›Suspected tibial plateau fracture with complex pattern

›Characterizes fracture morphology for surgical planning

›Ottawa Knee Rule positive with equivocal plain radiographs

›Assessment of bony avulsion injuries

›CT limitations

›Limited role in primary meniscal tear diagnosis

›Cannot directly visualize meniscal substance

›MRI remains superior for soft tissue evaluation

›CT arthrography

›Alternative when MRI is contraindicated (pacemaker, metal implant)

›Sensitivity approximately 90%, specificity approximately 89% for meniscal tears

Ultrasound

›Point-of-care ultrasound applications

›Detection of knee joint effusion

›Suprapatellar recess assessed in longitudinal view

›Effusion depth over 4 mm in suprapatellar recess considered positive

›Can guide aspiration if large effusion present

›Detection of bursitis or soft tissue swelling

›Ultrasound limitations for meniscal evaluation

›Not reliable for meniscal tear diagnosis

›Poor visualization of deep meniscal substance

›Cannot distinguish tear grade

›ACR Appropriateness Criteria: ultrasound not recommended as primary imaging for meniscal tears

›Sensitivity and specificity significantly inferior to MRI for meniscal pathology

07Disposition/dispo30

Discharge criteria

›Discharge from ED appropriate for

›Nondisplaced meniscal tear with preserved ROM

›Able to bear weight, no neurovascular deficit

›No red flags or alarm features

›Stable effusion without signs of septic arthritis

›Pain controlled with oral analgesia

›Discharge instructions and planning

›Crutches if partial weight-bearing required

›Knee immobilizer if significant pain with ambulation

›NSAIDs or acetaminophen prescription

›Orthopedic or sports medicine follow-up within 1-2 weeks

Urgent referral indications

›Same-day or next-day orthopedic referral

›Locked knee (inability to fully extend)

›Displaced bucket-handle tear until proven otherwise

›Suspected displaced or complex meniscal tear

›Concomitant multi-ligament injury

›Neurovascular compromise

›Suspected knee dislocation

›Urgent follow-up within 48-72 hours

›Large tense hemarthrosis requiring repeat aspiration

›Significant functional impairment

Observation or admission indications

›Admission rarely required for isolated meniscal tear

›Consider for suspected vascular injury

›Consider for compartment syndrome concern

›Septic arthritis requiring IV antibiotics

08Treatment/t92

Immediate management

›RICE protocol

›Rest from aggravating activities

›Avoid pivoting, twisting, deep squatting until further assessment

›Ice application

›15-20 minutes per application every 1-2 hours for 48-72 hours

›Compression

›Compressive wrap to limit effusion accumulation

›Elevation

›Above heart level to reduce swelling

Analgesia

›NSAIDs (first-line for acute pain)

›Ibuprofen

›400-600 mg orally three times daily with food

›Maximum 2,400 mg per day

›Short course of 5-7 days for acute phase

›Naproxen

›500 mg orally twice daily

›Maximum 1,000 mg per day

›Contraindications and precautions

›Renal impairment (eGFR under 30)

›Active GI bleeding or peptic ulcer disease

›Anticoagulation use

›Add PPI if GI risk factors present

›Evidence: no detrimental effect on healing per ACSM/AMSSM consensus

›Acetaminophen

›500-1,000 mg orally every 6-8 hours as needed

›Maximum 4,000 mg per day in healthy adults

›Maximum 2,000 mg per day in liver disease or alcohol use

›Alternative when NSAIDs contraindicated

›Acceptable as adjunct to NSAIDs

›Opioids

›Rarely indicated for isolated meniscal tear

›Reserve for severe acute pain when NSAIDs and acetaminophen inadequate

›If used, prescribe lowest effective dose for shortest duration

›2-3 days maximum; reassess before any extension

Adjunctive physical interventions

›Cryotherapy

›Ice packs or cold compression devices

›Reduces pain and swelling in first 72 hours

›Avoid direct skin contact (use cloth barrier)

›Knee immobilizer

›Indications: significant pain with ambulation, instability, or suspected displaced tear

›Not for long-term use in stable nondisplaced tears

›Crutches

›Partial weight-bearing as tolerated

›Full non-weight-bearing for locked knee pending surgical consultation

Conservative management (first-line for most tears)

›Physical therapy program

›AAOS Strong Recommendation: PT as first-line for nonobstructive meniscal tears

›Based on Level I evidence from multiple RCTs

›Neuromuscular exercises 1-2 times weekly

›Quadriceps strengthening

›Hamstring strengthening

›Balance and proprioception training

›Duration: minimum 3 months recommended before considering surgery

›ESCAPE trial evidence

›321 patients randomized to PT versus arthroscopic partial meniscectomy

›PT noninferior to surgery for knee function over 24 months

›Supports PT as primary management for nonobstructive tears (JAMA 2018)

›Activity modification

›Gradual return to activity as symptoms allow

›Avoid high-impact pivoting activities during acute phase

›Low-impact cross-training acceptable (cycling, swimming)

Surgical management

›Surgical indications

›Locked knee or displaced bucket-handle tear

›Prompt referral; surgery typically within days to weeks

›Meniscal root tears

›High OA progression risk if untreated

›Young active patient with reparable tear in vascularized zone

›Outer 10-30% of meniscus has blood supply from the periphery

›Early repair preserves meniscal tissue and protects against OA

›Failure of 4-6 weeks of conservative management

›Surgery within 6 months of symptom onset for best outcomes

›Arthroscopic partial meniscectomy

›Most common meniscal surgery performed

›Return to sport approximately 7-9 weeks

›Appropriate for irreparable tears in avascular zone

›Cochrane 2022: no benefit over conservative management for degenerative tears with OA

›Avoid in patients with pre-existing knee OA unless locked knee

›Evidence level: Class IIa recommendation based on RCT data

›Meniscal repair

›Return to sport approximately 5-6 months

›Longer recovery due to healing requirements

›Failure rate 14.8%

›Higher success when combined with ACL reconstruction

›Preferred over meniscectomy in young patients when technically feasible

›Requires vascularized peripheral zone tear for healing potential

Intra-articular injections

›Corticosteroid injection

›Not first-line in acute setting

›May mask symptoms and delay diagnosis

›Consider for older patients with degenerative tear and inflammatory flare

›Triamcinolone acetonide 40 mg or methylprednisolone 40-80 mg

›Hyaluronic acid injection

›Evidence limited; not recommended for acute traumatic tears

›May be considered for degenerative tears with concomitant OA

09Special Populations/sp80

Pregnancy

›Physiologic considerations in pregnancy

›Ligamentous laxity increases due to relaxin

›May affect joint stability and predispose to injury

›Weight gain increases mechanical load on knee

›Vascular changes may affect healing

›Diagnostic imaging in pregnancy

›Radiographs

›Use only if Ottawa Knee Rules criteria met and fracture must be excluded

›Shield uterus; radiation exposure to fetus is minimal with extremity X-ray

›MRI

›Preferred cross-sectional imaging; no ionizing radiation

›Avoid gadolinium contrast in first trimester unless essential

›MRI without contrast safe in all trimesters

›CT: avoid unless fracture characterization critical and MRI not available

›Medication safety in pregnancy

›Acetaminophen

›Preferred analgesic in pregnancy; generally considered safe

›Use lowest effective dose for shortest duration

›NSAIDs

›Avoid after 20 weeks gestation due to risk of premature ductus arteriosus closure and oligohydramnios

›May be used cautiously in first trimester only if clearly needed

›Opioids: avoid if possible; use only if benefit outweighs risk

›Surgical considerations in pregnancy

›Elective arthroscopy deferred until postpartum when possible

›If locked knee requires urgent intervention

›Multidisciplinary coordination with obstetrics and anesthesia

›Regional anesthesia preferred over general when feasible

Geriatric

›Epidemiology and pathophysiology differences

›Degenerative meniscal tears predominate in patients over 60

›Often associated with pre-existing knee OA

›Typically atraumatic or minimal trauma mechanism

›Asymptomatic meniscal tears common on MRI in this age group

›MRI findings must be interpreted in clinical context

›Diagnostic considerations in geriatric patients

›Ottawa Knee Rules remain valid in patients 55 and older

›Lower threshold for radiographs due to osteoporosis risk

›Tibial plateau fracture more likely from low-energy mechanism in osteoporotic bone

›Treatment modification in geriatric patients

›NSAIDs require caution

›Increased risk of GI bleeding, renal impairment, and cardiovascular events

›Use lowest effective dose; add gastroprotection

›Consider topical diclofenac as alternative with lower systemic exposure

›Acetaminophen preferred first-line analgesic

›Maximum 2,000 mg per day if frail or hepatic impairment

›Physical therapy first-line for degenerative tears

›Surgery not recommended for degenerative meniscal tears in patients with OA

›Cochrane 2022 evidence supports conservative management in this population

›Falls risk and functional assessment

›Crutch use may increase falls risk in frail patients

›Occupational therapy referral if concern for home safety

Pediatrics

›Epidemiology in pediatric patients

›Meniscal tears less common in skeletally immature patients

›Discoid meniscus predisposes pediatric patients to tear with minimal trauma

›Most common in adolescent athletes

›Often associated with ACL injuries in adolescents (JAMA Pediatrics 2021)

›Diagnostic considerations in pediatric patients

›Physeal injuries must be excluded before diagnosing meniscal tear

›Growth plate fractures (Salter-Harris) may mimic joint line tenderness

›Ottawa Knee Rules not validated for patients under 18; clinical judgment required

›MRI preferred over radiographs for soft tissue evaluation

›Avoids ionizing radiation

›Identifies physeal injury, osteochondritis dissecans, and discoid meniscus

›Discoid meniscus

›Congenital variant; lateral meniscus most commonly affected

›Presents with snapping, catching, and pain in children

›Saucerization surgery may be required

›Treatment in pediatric patients

›Conservative management appropriate for stable nondisplaced tears

›Physical therapy program adapted to developmental stage

›Surgical repair preferred over meniscectomy in skeletally immature patients

›Meniscal preservation critical to long-term joint health

›Partial meniscectomy accepted only for irreparable tears

›Medication dosing

›Ibuprofen: 10 mg/kg per dose orally every 6-8 hours

›Maximum 40 mg/kg per day or 2,400 mg per day, whichever is less

›Acetaminophen: 15 mg/kg per dose orally every 4-6 hours

›Maximum 75 mg/kg per day or 4,000 mg per day, whichever is less

›Return to sport considerations

›Functional criteria-based return rather than time-based

›Full ROM, strength symmetric to contralateral limb, no pain with sport-specific activities

10Background/b68

Epidemiology

›Incidence and prevalence

›Meniscal tears among the most common knee injuries

›Incidence approximately 60-70 per 100,000 persons per year in the general population

›Traumatic tears: young athletes predominantly under 40

›Soccer, basketball, football highest-risk sports

›Degenerative tears: middle-aged and older adults

›Prevalence increases sharply with age

›Detectable on MRI in over 40% of adults over 70 with knee pain

›Risk factor data

›Age over 60: OR 2.32 for degenerative meniscal tear

›Male sex: OR 2.98

›Occupational kneeling or squatting: OR 2.69

›Concomitant ACL injury strongly associated with traumatic meniscal tear

›Long-term outcomes

›Meniscal tears increase OA risk: pooled OR 6.33 compared with noninjured controls

›80-87% of athletes return to preinjury sport after meniscal surgery

›OA risk highest after meniscectomy compared with meniscal repair or conservative management

Pathophysiology

›Anatomy and biomechanics

›Two menisci per knee: medial (C-shaped, less mobile) and lateral (more circular, more mobile)

›Medial meniscus more commonly injured due to relative immobility

›Function

›Load transmission: each meniscus transmits approximately 50-70% of compressive load

›Shock absorption, joint lubrication, and stability augmentation

›Vascular supply

›Outer 10-30%: vascularized red zone (healing potential)

›Inner 70-90%: avascular white zone (no intrinsic healing capacity)

›Mechanisms of injury

›Traumatic tear

›Noncontact twisting or rotatory force with knee near full extension

›Femoral condyle traps and crushes meniscus against tibial plateau

›Bucket-handle tears occur when longitudinal tear displaces into notch

›Degenerative tear

›Cumulative mechanical stress over years

›Associated with OA cartilage loss and altered load distribution

›Tear classification

›By location: medial or lateral; anterior, body, or posterior horn

›By pattern

›Longitudinal: parallel to circumference; bucket-handle if complete

›Radial: perpendicular to circumference; disrupts hoop stress function

›Oblique or flap tear: can cause mechanical symptoms

›Horizontal: degenerative; parallel to tibial plateau

›Complex: multiple planes; typically degenerative

›Meniscal root tears

›Disruption of posterior root attachment to tibial plateau

›Catastrophic loss of hoop stress function; rapid OA progression if untreated

Therapeutic Considerations

›Conservative versus surgical decision-making

›Physical therapy equivalent to surgery for most nonobstructive tears

›ESCAPE trial: PT noninferior to arthroscopic partial meniscectomy over 24 months

›Supports PT as initial management regardless of patient age

›Surgery clearly indicated for locked knee or reparable tears in young patients

›Surgery not recommended for degenerative tears with OA (Cochrane 2022)

›No benefit of arthroscopy over conservative management in this group

›Healing potential and zone significance

›Peripheral red zone tears: healing potential with repair

›Early repair within 6-8 weeks optimizes outcomes

›Central white zone tears: no healing potential

›Meniscectomy of unstable fragment may be required

›OA prevention principles

›Meniscal preservation superior to meniscectomy for long-term joint health

›Loss of meniscal tissue directly increases contact stress on articular cartilage

›Weight management and exercise reduce OA progression risk

›Early repair with ACL reconstruction improves meniscal healing rates

›ICD-10 coding reference

›S83.201A: Tear of unspecified meniscus, current injury, right knee, initial encounter

›S83.202A: Tear of unspecified meniscus, current injury, left knee, initial encounter

›S83.211A: Bucket-handle tear of medial meniscus, right knee, initial encounter

›S83.221A: Peripheral tear of medial meniscus, right knee, initial encounter

›M23.200: Derangement of unspecified meniscus due to old tear or injury, right knee

11Patient Discharge Instructions/pdi33

copy discharge instructions

›Diagnosis and understanding

›Your knee injury is a meniscal tear

›The meniscus is a cartilage pad inside your knee that cushions and stabilizes the joint

›Meniscal tears are common and most can be treated without surgery

›Most people recover well with rest, physical therapy, and pain control

›Activity instructions

›Rest your knee from activities that cause pain

›Avoid twisting, pivoting, deep squatting, and impact sports until cleared

›Partial weight-bearing as your pain allows if crutches provided

›Use crutches as instructed to avoid putting too much weight on the injured knee

›Ice your knee for 15-20 minutes every 1-2 hours for the next 2-3 days

›Always place a cloth between the ice pack and your skin

›Elevate your leg above heart level when resting to reduce swelling

›Wear the knee brace or immobilizer as directed

›Medications

›Anti-inflammatory medication (ibuprofen or naproxen) as prescribed

›Take with food to protect your stomach

›Do not take if you have kidney disease, stomach ulcers, or blood thinners

›Acetaminophen (Tylenol) as an alternative or additional pain reliever

›Do not exceed 4,000 mg per day in a healthy adult

›Do not drive or operate machinery if taking strong pain medications

›Follow-up

›See an orthopedic surgeon or sports medicine doctor within 1-2 weeks

›Bring this discharge summary to your appointment

›Your doctor may arrange an MRI if one was not done today

›Physical therapy will likely be recommended as your primary treatment

›Return to emergency immediately if you experience

12References/r24

Guidelines and key sources

›Primary evidence sources

›Duong V, Oo WM, Ding C, Culvenor AG, Hunter DJ. Evaluation and Treatment of Knee Pain: A Review. JAMA. 2023

›Comprehensive review grounding history, physical exam, imaging, and treatment evidence

›American Academy of Orthopaedic Surgeons. Acute Isolated Meniscal Pathology Evidence-Based Clinical Practice Guideline. 2024

›AAOS CPG with Strong Recommendation for PT as first-line; combination of clinical tests superior to single test

›van de Graaf VA, Noorduyn JCA, Willigenburg NW, et al. Effect of Early Surgery vs Physical Therapy on Knee Function Among Patients With Nonobstructive Meniscal Tears: The ESCAPE Randomized Clinical Trial. JAMA. 2018

›321 patients; PT noninferior to arthroscopic partial meniscectomy at 24 months

›O'Connor D, Johnston RV, Brignardello-Petersen R, et al. Arthroscopic Surgery for Degenerative Knee Disease. Cochrane Database Syst Rev. 2022

›No benefit of arthroscopy over conservative management for degenerative tears with OA

›Herring SA, Kibler WB, Putukian M, et al. Initial Assessment and Management of Select Musculoskeletal Injuries: A Team Physician Consensus Statement. Med Sci Sports Exerc. 2024

›Management of acute knee injuries including meniscal and ligamentous pathology

›Diagnostic and imaging references

›Solomon DH, Simel DL, Bates DW, Katz JN, Schaffer JL. Does This Patient Have a Torn Meniscus or Ligament of the Knee? JAMA. 2001

›Physical examination performance: joint line tenderness sensitivity and specificity 83%; McMurray sensitivity 61%, specificity 84%

›Sims JI, Chau MT, Davies JR. Diagnostic Accuracy of the Ottawa Knee Rule in Adult Acute Knee Injuries: A Systematic Review and Meta-Analysis. Eur Radiol. 2020

›Ottawa Knee Rule sensitivity 99% for fracture across 7,385 patients

›Taljanovic MS, Chang EY, Ha AS, et al. ACR Appropriateness Criteria: Acute Trauma to the Knee. J Am Coll Radiol. 2020

›MRI recommended when diagnosis uncertain; CT for bony injury characterization

›Rinonapoli G, Lucchetta L, Ancillai G, et al. Clinical Reliability of 6 Meniscal Tests. Acta Orthop. 2025

›Diagnostic accuracy study of 255 patients; McMurray plus Apley combination best accuracy

›MacDonald J, Rodenberg R, Sweeney E. Acute Knee Injuries in Children and Adolescents: A Review. JAMA Pediatrics. 2021

›Pediatric knee injury assessment including physeal injury exclusion and meniscal considerations

›Hunter CW, Deer TR, Jones MR, et al. Consensus Guidelines on Interventional Therapies for Knee Pain (STEP Guidelines). J Pain Res. 2022

›Intra-articular injection guidance including corticosteroids and hyaluronic acid

Evidence & Review

Evidence & Review