Knee Pathologies

Question 1

Osgood Schlatter Disease

Answer 1

Inflammation of tibial tubercle prior to ossifying; benign and self-limiting condition that waxes and wanes and can take months to years to resolve; common in active, skeletally immature athlete, often after a growth spurt; Males: 10-15, Females: 8-13

Question 2

Sinding-Larson-Johansson Syndrome

Answer 2

Apophysitis of the inferior pole of the the patella at the growth plate; occurs most often ages 10-15 during period of rapid growth; more prevalent in kids who play sports that require running and jumping

Question 3

Patellar Tendinitis

Answer 3

Inflamed patellar tendon; acute (because -itis, not -osis); quadriceps tendonitis; history of repetitive jumping, running, or over use

Question 4

Fat Pad Syndrome; “Hoffa’s”

Answer 4

Anterior knee pain due to inflammation of the infrapatellar fat pad; due to direct trauma or chronic knee hyperextension “insideous onset”

Question 5

Knee Bursitis

Answer 5

Prepatellar bursa, suprapatellar, Pes anserine, Superficial and deep infrapatellar, semimembranosus/Gastrocs; repetitive microtrauma causes bursal irritation; produces more fluid to to lubricate adjacent tissues at the expense of absorbing friction; results in inflammation of the bursa

Question 6

Iliotibial Band Friction Syndrome

Answer 6

Tight ITB; hypertonic TFL?; Often over pronation at the foot, lateral knee pain and tenderness of ITB

Question 7

Baker’s Cyst

Answer 7

Most common mass in the popliteal fossa; fluid distension of the gastroc-semimembransosus bursa; synovial cyst, usually communicates with the joint lined by synovium

Question 8

Tibial Plateau Stress Fracture

Answer 8

Proximal 1/3 of tibia most common site for stress fractures in adolescents; in runners typically occurs near middle/distal 1/3rd; most frequent stress fracture location in military training

Question 9

PFPS

Answer 9

Vague anterior knee pain aggravated by activities that increase compression across the PFJ; most common in young and active population; females > males 12-17 yo; most common injury in runners; high incident of recurrence and chronicity

Question 10

PFJ Instability/Subluxation

Answer 10

Partial loss of contact between the patella and femur; lateral subluxation most common; females > males

Question 11

ACL Injury

Answer 11

Most often non-contact injury; acceleration/deceleration at full extension or slight flexion coupled with tibial rotation (IR/Valgus without HS co contraction and excessive quad contraction); females > males

Question 12

Arthofibrosis

Answer 12

Complication of injury or surgery; excessive scar tissue formation; intra and/or extra articuar; thought early ACL repair may increase likelihood or delay in regaining motion after surgery; marked limitation of flexion, extension, and patellar glide; widespread inflammation

Question 13

PCL Injury

Answer 13

MVA: “Dashboard injury” (posterior blow to the tibia -tibia thrusted posteriorly- with a flexed knee)
Contact sports: fall on a bent knee with their foot plantarflexed - tibia hits the ground first and it translates posteriorly; hyperflexion in external rotation

Question 14

MCL Injury

Answer 14

Valgus blow to knee or CKC with a plant/cut valgus stress; most common ligament strained of the knee; Most common injury in NFL/alpine skiing; second most common injury in collegiate hockey and women’s rugby; Grade III injury ~80% concomitant ligamentous injury (95% of the time = ACL)

Question 15

LCL Injury

Answer 15

Least commonly injured knee ligament; Usually with LCL injury there’s additional soft tissue injury (soft tissue avulsion of proximal femur or bony avulsion off fibular head); seen with more extensive posterolateral corner injuries (PLC)

Question 16

Meniscus

Answer 16

Common cause of mechanical sx at the knee; meniscal tear common; we all probably have something wrong with our menisci i.e. sometimes not symptomatic; sx indicate higher level of injury

Question 17

PLC (Posterolateral Corner)

Answer 17

Anatomy:
Muscles = popliteus, lateral head of gastroc, short head of biceps femoris
Ligaments = fibular collateral lig, arcuate ligament
Miscellaneous = Lateral Meniscus, lateral retinaculum
Prevents: Varus, and tibial ER primarily, Secondarily assists PCL with posterior tibial translation (30 degrees) and hyperextension

One of the most common multi-lig injuries; commonly missed with ACL

Question 18

Articular Cartilage Defects

Answer 18

Commonly at medial femoral condyle and patella articular surface; medial meniscus tears and ACL rupture most common concomitant injuries

Question 19

Tibiofemoral OA

Answer 19

Degradation of articular cartilage at tibfem joint

Question 20

Patellofemoral OA

Answer 20

PF pain + radiographic changes consistent with changes

Question 21

Chondromalacia patella

Answer 21

PF OA; often indicates softening of the carilage on the posterior aspect of the patella, not common; chondral legions usually asymptomatic until bone is irritated

Question 22

Patellar Tendinopathy/Tendinosis

Answer 22

Non-inflammatory disorder of the tendon typically occurring near the inferior pole of the patella; common among athletes involved in jumping activities

Question 23

Popliteus Tendonitis

Answer 23

Inflammation of the popliteus tendon; common in runners

Question 24

Acute tendon ruptures that happen

Answer 24

Quad and Patella tendon

Question 25

Other possible fractures at the knee

Answer 25

Femur or patella fractures

Question 26

Peripheral Nerve injuries possible

Answer 26

Saphenous (confused with pes anserine problems; medial knee pain, typically worse at night, increased with limb activity)
Superficial peroneal (compression or direct blow pain, parasthesias over lateral leg, possible motor weakness)

Question 27

Medial plica syndrome

Answer 27

Plica that has become symptomatic due to:
direct trauma/blow to plica, blunt trauma, twisting injury, activities requiring repetitive flex/ext of knee, increased activity levels, mechanism resulting in intraarticular bleeding or synovitis secondary to a loose body, osteochondritis dissecans a torn meniscus, a subluxing patella or after arthroscopy