Evaluation of Knee Problems

OBJECTIVES• Review knee anatomy• Explain tests to look for pathology• Briefly introduce knee problems

Only by a thorough knowledge of anatomy and functional testing can one make an

accurate diagnosis and direct effective care to an injured

knee.

Ligamentous Anatomy

• Hinged Joint• ACL: Ant Stability• PCL: Post Stability• Lat/Med Stability:

LCL/MCL• Menisci:

Medial/Lateral

EXTENSOR MECHANISM

The QuadricepsORIGINS:

•Rectus Femoris: AIIS

•Vastus Group: Linea Aspera

INSERTIONS:

•Patella

•Patellar Retinaculum

Always have the patient perform a straight leg raise to rule out an extensor mechanism rupture after

acute trauma

FLEXOR MECHANISM

The HamstringCOMMON ORIGIN:• Ischial Tuberosity

INSERTIONS:•Biceps: Fibular Head

•Semimembranosus: Medial Tibial Condyle

•Semitendinosus: Pes Anserinus

History• Chief Complaint• Antecedent event/Repetitive activity• Previous injuries to affected area• Attempted therapies• Review of symptoms/Past medical

history• Occupation/Treatment Goals

Inspection• Lower extremity alignment• Foot structure• Effusion/Erythmea• Q Angle• Thigh atrophy

Foot Structure Variants

Pes Planus Pes Cavus

Ballotment Test for Effusion

Causes of Traumatic Effusion

1. ACL tear2. Meniscal tear3. Patellar dislocation4. Fracture5. Others (PCL, MCL, LCL)

Quadriceps Angle(Q Angle)

=The Angle between:

1) ASIS to center of Patella and

2) Patella to Tibial Tubercle

NORMALMen <10°

Women <15°

Thigh Atrophy• Possible sign of intra-articular

pathology• Measure either hand breadth above

patella or 10cm above patella –Measure 2 times

• > 1 cm different is abnormal

Leg Length

• FUNCTIONAL METHOD: Compare heights of ASIS & PSIS– Add foot shims in small adjustments until level

• ANATOMICAL METHOD: Measure from ASIS to Medial Malleous– > 1 cm difference is significant

• Pelvic Obliquity will confuse issue

• RADIOLOGIC METHOD: Scanogram (X-ray)– most definitive but usually not needed

Range Of Motion

Palpation of key structuresMedial:

• MCL• Pes anserinus• Medial meniscus• Plica (ant-med)

Lateral:• LCL• ITB/lateral

femoral condyle• Lateral meniscus• Fibular head

Anterior:•Patellar tendon•Patella•Tibial tubercle•Fat pad

Posterior:•Popliteus•Baker’s cyst

Osgood-Schlatter’s DiseaseClinical Description

• The most common overuse injury seen in young athletes

• Traction apophysealinjury– seen in

running/jumping athletes during periods of rapid growth

Osgood-Schlatter’s DiseaseClinical Features

• History – young athlete complains of painful

enlargement of the tibial tuberosity– pain worse with activity, esp. run/jump

• Exam– tender tibial tuberosity– tight quads +/- hamstrings

• Imaging: usually not necessary

Osgood-Schlatter’s DiseaseImaging

• Use in severe or persistent cases to rule out other problems

• Not used to make the diagnosis in most cases

• May show fragmentation of the anterior tibial tuberosity

Osgood-Schlatter’s DiseaseDifferential Diagnosis

• Sinding-Larsen-Johansson Disease• Tibial neoplasm e.g. osteochondroma• Patellofemoral pain syndrome• Patellar tendonosis• Tibial tuberosity avulsion fracture

Osgood-Schlatter’s DiseaseTreatment

• Relative rest; cross-training • Ice • Hamstring stretching• Strapping of patellar tendon• Rare: temporary immobilization• Return to play:

– Pain-free with sports activity

Osgood Schlatter’s Disease Surgery Indications

• Persistent, painful osafter growth complete

Sinding-Larsen-JohanssenDisease• Apophysitis of distal patella• Pain with kneeling and squatting.• Tender at distal patellar pole• Calcification is sometimes

present at site of tenderness.• Natural history: resolution in 6 to

10 months.• Tx: ice, relative rest, ham/quad

stretching

Patellar Grind Test

• Detects pain from patellar pressure against femur

• Compress patella against femoral groove– Gentle way: pressure with fingers– Most sensitive way: press down above patella;

have patient contract quads• POSITIVE:

– Pain – Crepitus

Management of Patello-Femoral Syndrome

• Cross-training; avoid painful activity• VMO strength ex’s• Flexibility ex’s (quad, hams, ITB, Achilles)• Retinaculum stretching • Patellar sleeve w/ cutout• Correct hyper-pronation• Referral:

– refractory cases w/ high Q angle, tight retinaculum, severe crepitus

Patellar Glide: nl is 25-50% of width.

POSITIVE TESTS:•Inflexibility•Subluxation

•(+ Apprehension)

Lateral

Management of Patellar Dislocation

• X-rays to r/o shearing fracture– AP, lat, sunrise

• Knee immobilizer/cast in ext 3 weeks• ROM/strength ex’s as pain allows• Refer for:

– Locking– Fracture– Recurrent dislocations

Medio-Patellar Plica

Management of Medio-Patellar Plica Syndrome

• Cross-training/relative rest• NSAID 1-2 weeks• Phonopheresis• Injection w/ anesthetic/steroid• Referral: failed 6 months tx

Management ofPatellar Tendinopathy

• Avoid NSAID overuse• Restrict from further

abuse• Patellar strap (ChoPat)• Progressive eccentric

strength ex’s 3-6 mos

Treatment of Pre-Patellar Bursitis

• Aspirate fluid (culture, cell count)• Compressive dressing• Treat suspected septic bursitis with

oral antibiotics–Dicloxacillin or fluoroquinolone

• NSAIDs• F/U at 4 days

– Consider intra-bursal steroid injection

Joint Stability Testing

• MCL: Valgus Load• LCL: Varus Load• ACL: Lachman, Ant drawer, Pivot

Shift• PCL: Posterior Drawer, Sag sign,

Quadriceps Active• Postero-lateral complex: Ext Rot

MCL Stability

Apply Valgus or Medial Stress

Test in 30°flexion

LCL Stability

Apply Varus or Lateral Stress

Grading collateral ligament injuries

• Grade I: mild; no laxity• Grade II: partial tear; laxity w/ firm end-

point• Grade III: complete tear; laxity w/o firm

endpoint

• Why does it matter? Prognosis

Treatment of MCL/LCL injuries

• PRICEMM• Grades I-II

– knee immobilizer until pain gone– ROM/strength ex’s as pain allows

• Grade III: – r/o associated injuries– knee immobilizer at 30° NWB 3 weeks– knee immob 30-80 ° NWB 4 wks– progressive ROM/strength ex’s

ACL anatomy

Tests of ACL

At 90° Flexion

At 20-30 ° Flexion

(more sensitive)

+ is increased translation or soft end point

Lachman test

Pivot Shift: ACL Injury

1. Knee extended

2. Internally rotate tibia

3. Apply valgus load

4. Flex Knee

5. At 20-30°, if you feel a jerk at Ant/Lat proximal tibia, test +

Management of ACL tears

• PRICEMM• ROM/strength ex’s as pain allows• MRI• Referral to Orthopedics

– Surgery once edema gone– Graft options

• Bone-patella-bone autograft• Hamstring autograft• Cadaver allograft

PCL Tear

PCL TESTS: Posterior Sag

Quad Active Test

Posterior Drawer

Management of PCL tears

• PRICEMM• Immobilize; refer to Ortho• If no associated injuries:

– ROM /strength ex’s as pain allows• If associated with other injuries:

– Surgical repair• MCL• Postero-lateral corner

Flex knees to 30°.Externally rotate tibia.Injured limb will have

external rotation.

Repeat at 90° flexion (persistent incris from combined PLC/PCL injury)

Injury to Postero-Lateral Corner

External Rotation Test

Popliteus Tendonitis• Function: resists posterior

translation of tibia• Pain postero-lateral• Garrick Test: pain with resisted ext

rotation of leg• Seen w/ downhill running• Treatment:

– Modify running– NSAID/ice– Hamstring stretching– Eccentric quad strength– Refer for injection if not responding

Popliteus

Flexibility testing

• Inflexibility is a common culprit in overuse– Hamstring– Quadriceps– Ilio-tibial band (ITB)– Gastro-soleus complex– Patellar glide and tilt

Quadriceps flexibility

Hamstring flexibility:

Popliteal Angle

Goal: 0°

Gastro-soleus flexibility

ITB flexibility:

Ober test

•Tight ITB will remain ABducted

•Pain = ITB injury

Ilio-Tibial Band Friction Syndrome

Management of ITB Friction Syndrome

• Reduce run mileage/hills/banked surfaces• NSAID/ice massage/phonopheresis• ITB stretching• Correct overpronation• Gradual return-to-running program• Referral for injection if fail above

Miscellaneous Tests

• McMurray: Meniscal injury• Apley Test: Meniscal vs ligament injury • Bounce Home Test: meniscal injury, effusion• Patellar grind test: PFS, chondromalacia

Normal Meniscus Meniscal Tear

McMurray TestMEDIAL MENISCUS:• Flex knee maximally• Externally rotate tibia• Varus stress• Extend Knee

+ is painful pop over Medial or Lateral Joint Line

LATERAL MENISCUS:•Flex knee•Internally rotate tibia•Valgus stress•Extend knee

McMurray Test

Apley testCompression forMeniscal Injury

Distraction for Ligamentous Injury

Full Flexion TestPain at full flexion suggestive of posterior horn tear

Bounce Home Test

Abnormal is lack of full extension (meniscal tear, loose body, effusion)

1. Flexion

2. Passive Extension

Normal

The accuracy of physical diagnostic tests for assessing meniscal lesions

of the knee: A meta-analysis.

Bijl D et al. JFP Nov 2001;50(11)

•The diagnostic accuracy of meniscal tests is poor•These tests are of little value for clinical practice.•McMurray test and joint line tenderness indicatedlittle discriminative power for these tests. •Only the predictive value of a positive McMurray test was favorable.

Management of Meniscal Tears

• Weight-bearing as tolerated• ROM/strength ex’s as pain allows• MRI to confirm if recovery not prompt• Indications for referral:

– Elite athletes– Symptomatic after 3 months– Locking– Unable to fully extend knee

Who needs knee xrays after trauma?Ottawa Knee Rules:

Any of the following:• Age < 1 or >55• Tenderness over patella• Tenderness over fibular head • Inability to walk 4 steps immediately and

when examined• Unable to flex knee 90d100% sensitivity and neg predictive value

Osteochondritis DissecansClinical Features

• History– Vague activity-related knee pain– +/- clicking, locking, giving way

• Physical Exam– Decreased or painful motion– May be effusion– Poorly localized joint line

tenderness

Wilson Test

THE PHYSICIAN AND SPORTSMEDICINE - VOL 26 - NO. 8 - AUGUST 98

•Imaging•Tunnel View reveals radiolucent area• Bone scan if x-rays negative•MRI best for staging, prognosis

Osteochondritis DissecansTreatment

• Orthopedic Consultation• Stage 1: Conservative

– Activity restriction or immobilization 6-8 wks

– Surgery if fails to heal• Stage 2: Controversial• Stages 3 & 4: Operative

THE PHYSICIAN AND SPORTSMEDICINE - VOL 26 - NO. 8 - AUGUST 98

Review

Only by a thorough knowledge of anatomy and functional testing can one make an

accurate diagnosis and direct effective care to an injured

knee.