originates below the adductor tubercle and attaches to the upper medial tibia

- limits abduction and assists in controlling rotation

- Commonly injured from valgus force (hit to outside of knee) or severe torsion

attaches to the lateral epicondyle of the femur and head of the fibula

- controls adduction

- common mech of injury: varus force, internal rotation

attaches to intraarticular portions of the femur and tibia

- prevents anterior displacement of the tibia and helps control rotation of the tibia on the femur

attaches to intraarticular portions of the femur and tibia

- prevents backward displacement of the tibia on the femur (posterior translation)

- 1° stabilizer of the knee

- can rupture if tibia moves too far back

- mech of injury: direct blow to front of bent knee (knee into dashboard, fall on bent knee)

 most important group of muscles related to the knee

- control extension and prevent dislocation of the patella

aka semilunar cartilages

-2 C shaped structures composed of fibrocartilage that help act as cushions between the femur and tibia, absorb shock under high loading, during running and jumping

-distribute load across entire tibial plateau

- stabilize knee joint (creates a shallow cup to hold femoral condyles)

-also assist with control of normal knee motion

occur with abnormal rotation of the tibia as the knee extends of flexes (if flexion occurs with external rotation or extension occurs with internal rotation)

- most common of all knee injuries

- medial meniscus is injured 10X more often

- common in conjunction with OA of the knee

In young pts: mech is a twist with knee flexion; can be associated with ACL or MCL tears

In older pts: mech is meniscus has lost its elasticity, strength and resilience. Symptoms occur gradually

-usually preceded by twisting injury to the knee

-often a popping or tearing sensation felt followed by severe pain. 

- locking occasionally occurs, as does buckling

- swelling/stiffness from joint effusion gradually occurs over several hrs

- most pts can ambulate after injury and may continue to play game

- untreated pt will present weeks later with painful clicking, popping, locking or giving way 

Conservative (unless locked) RICE

- Robert Jones splint or crutches

-gentle ROM/strength exercises 

- gradual return to activity

-surgery only for true irreducible locking or recurrent s/s of injury

Refer: -locking/giving way >3-4 weeks → surgery

-no sig improvement in 3-4 weeks

2 types: Popliteal cyst (bakers), meniscus cyst

-bakers: enlargement of the semimembranous bursa in the medial aspect of the popliteal fossa

-Seen in children, and adults. (in adults usually due to underlying condition)

-Meniscus: usually in the lateral

-can occur with or without contact (ie, from deceleration or sudden stop, straight knee landing...)

- Mech: often occur as a result of twisting injury (external rotation) or vagus stress

- a pop or tearing sensation is often described

- feeling that the knee is coming apart or giving way

- +/- effusion, toe walk with flexed knee

- joint fills rapidly with blood, swelling within 1st few hrs

- positive anterior drawer test (anterior movement >5mm)or lachman test (>4mm forward translation with a soft end feel)

-mechanism: valgus force (ie hits to the outside of the knee in contact sports) or severe torsion

- test stability with valgus stress test at 30° and 0 °of knee flexion

- get Xray (lat, AP, oblique, tunnel view if suspected tibial plateau fracture)

-MRI if joint line pain >4-6 wks, accompanied by swelling/effusion

Grade 1: minimal, few fibers torn

+ stiffness, full ROM, pt tender over MCL

Joint is stable

Degrees of opening = 0-5mm

Grade 2: degrees of opening = 6-10mm

Grade 3: complete tear of superficial and deep layers

sig swelling over ligament, loss of ROM, laxity at 25° and 0°

Degrees of opening= 11-15mm

>15 degrees laxity at 25° flexion: associated ACL/medial meniscus injury

mechanism: varus force or internal rotation

Exam: tender LCL, + laxity with varus stress at 20-30°. Laxity at 0 may involve lateral and posterior joint capsule tear

Xray: get lateral, AP, oblique. Tunnel view if tibial plateau fx suspected

- R.I.C.E (rest, ice, compression dressing, elevation)

- NSAIDs

- short hinge knee brace with 20° extension block

- grades 1&2: WBA

- grade 3: initial NWB, progress to PWB by wk2, FWB by wk4 

- Rehab exercises: early ROM, isometric exercises immediately; progress as tolerated to: closed chain exercises (leg press, toe raise, mini-squats, cycling), exercise band, Pre's once 90° flexion achieved)

Grade 1&2: after 4-6 wks of rehab       

may no longer need brace

may return if able to pass all functional testing

Grade 3: may take 8-12 wks to return 

Heals slower than the MCL

Grades 1 & 2: non operative

-WBAT

-Hinged knee brace

Grade 3: usually not isolated LCL tear (uaually involves posterolateral corner of the knee:

- Refer

- Hemarthrosis or ligament instability require further eval (refer)

- failure to respond to conservative manag. may indicate a missed dx of ACL or meniscal tear

tests for minor effusion

- Use thumb an index finger used to milk down any fluid above the knee.

- stroke the medial side of the knee, with the other hand, to empty the medial compartment of fluid. Repeat on lateral side. 

- bulging on opposite side that is stroked indicated effusion

Used to test for major effusion

-slide hand down pt thigh, pushing down over suprapatellar pouch, so any effusion is forced behind the petella

- once upper pole of the patella is reached keep hand there and maintain P

-use index and middle fingers of other hand to push patella down gently

-if bounces: major effusion indicated

•  XRay
•  Joint aspiration: bloody
• Gold standard: arthroscopy
• MRI 90% accuracy
• US is low cost mode for rupture and traumatic hemarthrosis detection

- ICE, NSAIDS, immobilizer, joint aspiration ortho referral 
- Rehab:

Grades 1&2: hinged knee brace, closed chain exercises, ↑quad and hamstring strentgh for life

Grade 3: reconstruction is an option → Refer

*associated collateral ligament and meniscal tears are difficult to dx and can impact outcomes, when in doubt refer

Mech: abnormal patellofemoral tracking 2° to: tight hamstrings or lateral retinaculum, increased Q angle, tight I.T.B, pronation, VMO insufficiency

Hx: anterior knee aching, swelling, grating sensation, pain on stair climbing, descending, kneeling, squatting, prolonged sitting

Exam and tmt same as chondramalacia patella

McMurray test

Apley test

Full squat

associated MCL laxity

Tests for meniscal tears, very nonspecific (60% accurate)

- Flex knee, internally and externally rotate tibia on the femur

- With leg externally rotated, place valgus stress on the knee

- with leg externally rotated and in valgus, slowly extend the knee

-may illicit a painful click in the medial or lateral joint line: +

+: reproduce the clicking, locking or pain of a torn meniscus

- pt lays on belly, flex knee to 90°

- give firm downward P on the heel

- internally and externally rotate the tibia to the femur

• (1-3 hr)
• Usually indicates hemarthrosis due to significant intra-articular trauma
• Fracture
• ACL

• Deceleration or sudden stop: ACL
• Cutting: Medial meniscus, MCL, ACL

End feel

firm: intact ligament

mushy: partial tear

soft: probable grade 3 tear 

Based on degrees of opening at 0 and 25° flexion

Grade 1: 0-5 mm

Grade 2: 6-10mm

Grade 3: 11-15mm

• Must get Xrays for suspected tears (r/o fx or other causes)
  • AP, LAT, Oblique b/l
  • Tunnel view for suspected tibial plateau fx
• MRI: joint line pain>4-6 wks, with swelling
  • useful to ID associated meniscus or CL tears

- external rotation/ valgus stress

- sudden decelleration

- Planting and cutting straight knee landing

- 1 step stop with knee hyperextended

- Straight knee landing

Deterioration of articular cartilage of patella

Stage 1: swelling and softening

Stage 2: Softening and fissuring

Stage #: fragmentation and deformation

Mech, exam, diagnostics and tmt same as PF