Knee Pathologies and Special Tests

Active ROM normative values

Flexion= 135°

Extension= 0 to -5°

Medial tibial rotation= 10-20°

Lateral tibial rotation= 20-30°

Infrapatellar fat pad contusion

MOI- knee hyperextension that impinges the infrapatellar (IP) fat pad

S/S- pain, swelling, and point tenderness deep to and on either side of the patellar tendon

- ROM is limited in knee extension and patient will be apprehensive about fully extending the knee b/c of increased pain

- may complain of knee giving out with activity as result of unconsciously avoiding pain into extension

Quad contusion

MOI- muscle sustains direct contact while contracted

S/S- significant pain, spasm, and loss of function immediately

- ROM into flexion will be limited secondary to pain and spasm, but gentle stretching and ice with knee flexed may help

- w/ more severe= considerable hemorrhage and swelling can occur the 24-48 hours following injury

- may note discoloration and palpable hematoma

increase in leg circumference of 2.5 cm (1 in) or more= significant hemorrhage

Myositis Ossificans

MOI- potential consequence of quad contusion= body's inflammatory response during hematoma absorption causes calcification or forms bony deposits in the muscle

most often occurs secondary to severe hemorrhage, repetitive insult, or a return to activity that is too aggressive or too early following a severe contusion

S/S- hx of severe or repetitive insult to the quads, pain, or palpable mass within muscle belly

- decreased knee flexion ROM

- decreased quad strength

- and radiographic evidence within 3-4 weeks after injury

Traumatic Bursitis

MOI- direct contact over one of the superficial bursa (falling on the knee and making knee-to-knee contact with another player are most common)

most prone= prepatellar, suprapatellar, infrapatellar, and pes anserine

S/S- immediate observable bursal swelling, redness, and mild pain, warm to touch, can palpate soft, fluid-filled pouch

- Limited ROM with flexion results from swelling and increased pressure in the bursa as the skin tightness over the knee during flexion

Anterior Cruciate Ligament Sprain

MOI- both contact and non-contact. Contact= foot planted and laterally rotated when a valgus force is applied to the lateral aspect of the knee with knee slightly flexed

Non-contact (the majority of acl injuries)= sudden deceleration or change of direction, knee at near full extension

S/S- immediate pain and unwillingness to move the knee, may hear a pop at time of injury

- large joint effusion and loss of motion usually result within 24 hrs

- may be unwilling to bear weight or have a sense of weakness or instability with weight-bearing

- will note anterior and rotatory instability with stress tests on 2° and 3° sprains

Sweep Test

Assesses- minimal joint effusion

Patient position- supine with knee in full extension and thigh relaxed

Clinician position- standing at patient's side

Stabilizing hand- over lateral aspect of knee, hand is flat and in full contact with thigh

Test hand- over medial inferior aspect of knee area; hand is flat and in full contact with leg

Action performed- beginning at the distal medial knee joint margin, move the flat hand upward into the suprapatellar pouch, sweeping toward the hip. The other hand strokes downward on the lateral side of the patella toward the little toe

Positive result- a small bulge or wave on the medial aspect of the knee just inferior to the patella within 1 to 2 seconds

Ballotable Patella test

Assesses- moderate to severe knee effusion

Patient position- supine with knee in comfortable position near extension

Clinician position- standing at patient's side

Test hand- at patella

Action performed- light pressure or a tap is applied to the top of the patella

Positive result- patella bounces or seems to float or bob

Lachman test

Assesses- integrity of ACL

patient position- supine with knee relaxed in 20-30° of flexion, and neutral rotation (loose-pack position)

Clinician position- standing next to patient's lower extremity

Stabilizing hand- grasping the anterolateral aspect of distal thigh to stabilize femur

Test hand- grasping the medial proximal tibia just below the knee joint

Action performed- apply a posterior-to-anterior translational force to the tibia while stabilizing the thigh

Positive result- abnormal anterior translation of tibia on femur and pain compared to uninjured side; soft or absent end feel

Lateral Pivot Shift Maneuver test

Assesses- anterolateral rotatory instability and integrity of posterolateral capsule along with ACL, arcuate complex, LCL, IT, and posterolateral capsule

patient position- supine with hips in 30° of abduction, 30° of flexion, 20° of medial rotation

Clinician position- standing by patient's knee facing patient's head

Stabilizing hand- heel of hand behind fibula, over lateral gastrocnemius muscle

test hand- grasping ankle and holding leg in slight medial (internal) rotation

Action performed- apply a valgus stress to the knee while maintaining the medial rotation of the tibia and moving the knee from full extension into flexion

Positive result- if the test is positive and the IT band is intact, the tibia will sublux anteriorly on the femur when positioned in full extension. As you flex the knee, you will feel a palpable and at times audible reduction of the tibia relative to the femur between 20-40° of knee flexion as the IT band's line of pull changed from that of a knee extensor to that of a knee flexor

Anterior Drawer test

Assesses- integrity of ACL

Patient position- supine with hip flexed about 45° and knee at 90° of flexion so foot is flat on table

Clinician position- sitting on patient's foot to stabilize limb

Stabilizing hand- works with test hand in a mirrored position

Test hand- surrounding the knee with the fingers around the posterior aspect and both thumbs over the anterior joint margin

Action performed- with patient relaxed the hands pull the tibia forward on the femur

positive result- motion greater than 4-6 mm, or about 0.15 to 0.24 in or greater than the uninvolved side with soft or absent end feel indicating injury to the ACL

Posterior Drawer test

Assesses- integrity of PCL

Patient position- supine as in anterior drawer test

Clinician position- as in anterior drawer test

Stabilizing hand- as in anterior drawer

Test hand- as in anterior drawer test

Action performed- push the tibia posteriorly on the femur

Positive result- palpable and visual posterior translation of the tibia on the femur and a soft or absent end feel

Posterior Sag Sign

Assesses- integrity of PCL, posterior capsule, arcuate complex, may also indicate pathology of IT band and LCL

Patient position- supine with knee flexed to 90-110° and hip flexed to 45°, foot flat on table with quads completely relaxed

Clinician position- standing at patient's side and viewing knee from the side

Stabilizing hand- not needed

Test hand- lifting patient's legs to place hips and knees at 90°

action performed- with patient relaxed, observe for any sag of the involved tibia on the femur

Positive result- tibial plateau sits posteriorly on the femur compared to the uninvolved limb

Quadriceps Active test

Assesses- integrity of the PCL

patient position- sitting or supine with hip flexed and knee flexed at 90° with foot flat on table

clinician position- standing next to patient's leg

stabilizing hand- at distal thigh to stabilize hip

test hand- at ankle

action performed- instruct the patient to slide the foot forward into your hand at the ankle without extending the knee (to elicit isometric quadriceps contraction)

positive result- anterior reduction of the tibia relative to the femur during contraction

Posterior Cruciate Ligament sprain

MOI- injured secondary to a direct blow to the anterior tibia that drives it posteriorly on the fixed femur (making contact with dashboard during traffic collision and falling on the anterior tibia with the knee flexed and the foot+ankle is plantarflexed, any hyperextension or hyperflexion mechanism that forces that tibia posteriorly in relation to the femur can stretch or tear the PCL and posterior joint capsule

S/S- pain, joint effusion, limited ROM into full flexion and extension

- with complete rupture may hear pop at time of injury

- with 2 or 3° injury may see posterior sag

- athletes with PCL tears often do well following rehab and return to full activity without surgical interventions

Medial Collateral Ligament Sprain

MOI- straight valgus stress can result in isolated MCL injury, typically foot it planted in neutral or lateral rotation when contact is made to the lateral aspect of the abducted leg, resulting in a valgus stress to the medial joint structures

with severe valgus injuries, the ACL and medial meniscus are commonly injured also (ie. the unhappy triad) if the valgus force continues once the MCL fails

S/S- pain, mild to moderate swelling, discoloration, and point tenderness in the middle portion of the MCL or near its femoral or tibial attachment

- pain may also occur at the medial joint line if the deep portion of the ligament or its attachment to the medial - meniscus is torn

- usually no joint effusion

- pain when ligament in taut during full knee flexion and extension as well as valgus stress test

- may also note instability during the valgus stress test with 2nd and 3rd° injuries

Valgus Stress test

Assesses- integrity of MCL and other inert and active structures providing medial joint stability

Patient position- supine and extremely relaxed

Clinician position-standing next to patient's lower extremity

Stabilizing hand- grasping distal medial leg

test hand- grasping lateral aspect of knee

action performed- with knee in extension and then in 20-30° of flexion, the hand on the lateral knee acts as a fulcrum while the hand on the leg applies a lateral force to the tibia to gap the medial joint

positive result- laxity (gapping of joint margin) and pain consistent with 1st, 2nd, and 3rd ° sprains

Lateral Collateral Ligament Sprain

MOI- varus force applied to the medial aspect of the knee, most vulnerable when the varus force occurs while the leg is adducted and the tibia is medially rotated. Happen most often in contact sports such as football, soccer, and wrestling when one players falls into or makes contact against the medial side of another player's planted lower extremity

S/S- pain, lateral knee swelling, ecchymosis, and point tenderness over the LCL

- may feel a pop with complete rupture

- note varus instability with 2nd and 3rd° injuries

- athlete experiences increased pain when ligament is tensed during full knee flexion and extension and during varus stress test

- pain and swelling also limit ROM

Varus Stress Test

Assesses- Integrity of LCL and other inert and active structures providing lateral joint stability

Patient position- supine and extremity relaxed

Clinician position- standing next to patient's lower extremity

Stabilizing hand- grasping distal lateral leg

Test hand- grasping medial aspect of knee

Action performed- with knee in extension and then in 20-30° of flexion the hand on the knee acts as a fulcrum while the hand on the leg applies a medial force to the tibia to gap the lateral joint

Positive result- laxity (gapping of the joint margin) and pain consistent with 1, 2nd, and 3rd° sprains

* + sign in extension indicates serious instability of the lateral knee (arcuate complex, ACL, PCL, biceps femoris tendon, IT band, lateral gastrocnemius may be involved)

* knee in slight flexion= mostly just LCL

*lateral rotation + knee flexion adds additional stress to LCL

Anteromedial rotary instability

- most common

- occurs when the medial tibial plateau subluxes on the femur

- results when the ACL, MCL, posteromedial capsule, and possibly medial meniscus are torn

MOI- lateral rotation of tibia with valgus stress

Anterolateral rotary instability

- results from injury to ACL, LCL, posterolateral capsule, and may involve the arcuate complex, PCL, and IT band

- subluxation of the lateral tibial plateau with anterior translation and medial rotation of the tibia on the femur

Posterolateral rotary instability

- allows posterior subluxation of the lateral tibial plateau

- caused by injury to the posterolateral compartment, PCL deficiency, or both

- usually include the LCL and popliteus tendon, can include biceps femoris and lateral head of gastroc

MOI- anterior blow to the tibia with the foot laterally rotated and the knee under varus stress

Posteromedial rotary instability

- results from combined injury to the PCL, MCL, and medial joint capsule

MOI- anterior blow to tibia with knee partially flexed and under valgus stress and the foot laterally rotated

- note instability with valgus stress, posterior translation, and medial rotation of tibia

Slocum Test for Anterolateral Rotary Instability

Assesses- ACL, posterolateral capsule, arcuate complex, LCL, PCL, and IT band

Patient position- Supine with hip flexed to 45° and knee to 90°. Foot is flat on table (drawer test position), positioned in 15-30° of medial rotation to tighten structures of posterolateral corner

Clinician position- sitting on patient's foot to anchor lower-limb position during test

Stable hand- both hands work together to produce the test

Test hand- fingers behind proximal tibia with thumbs over anterior joint margins

Action performed- translate the tibia forward on the femur

Positive result- lateral side of the tibia moves forward more than on the uninvolved knee

Slocum Test for Anteromedial rotary instability

Assesses- ACL, posterolateral capsule, MCL, posterior oblique ligament

Patient position- Supine with hip flexed to 45° and knee to 90°. Foot is flat on table (drawer test position), positioned in 15° of lateral rotation to tighten structures of posteromedial corner

Clinician position- sitting on patient's foot to anchor lower-limb position during test

Stable hand- both hands work together to produce the test

Test hand- fingers behind proximal tibia with thumbs over anterior joint margins

Action performed- translate the tibia forward on the femur

Positive result- medial side of the tibia moves forward more than on the uninvolved knee

Side-lying Slocum Test

Assesses- anterolateral rotary instability

Patient position- side-lying with uninvolved leg down and flexed forward; involved side up and fully extended with tibia medially rotated to allow medial heel to rest on table (torso and pelvis rotated posteriorly)

Clinician position- at side of table near patient's leg

Stable hand- grasping lateral side of the distal end of the femur with the thumb over the posterior aspect of the lateral femoral condyle

Test hand- grasping lateral side of knee with thumb overlying the posterior aspect of fibula and index finger palpating the anterolateral joint line to monitor tibiofemoral relationship

Action performed- with equal pressure on the lateral femoral condyle and fibular head, push the knee gently into forward flexion

Positive result- palpable and audible reduction of the tibia relative to the femur (called a pivot shift or jerk sign) as the IT band changed from a knee extensor to a knee flexor

Hughston's Test

Assesses- anterolateral rotary instability

Patient position- supine with hip flexed to 45° and knee flexed to 90°

Clinician position- standing at patient's side

Stable hand- on distal leg to maintain tibia in medial rotation

Test hand- at lateral knee

Action performed- apply a valgus stress and simultaneous knee extension while maintaining tibial medial rotation

Positive result- at 20-30° of flexion, the lateral tibia jerks forward as the lateral tibial plateau subluxes

McMurray's Test

Assesses- integrity of meniscus

Patient position- supine

Clinician position- standing at patient's side

Stable hand- on top of knee with thumb over one joint line and index and middle fingers over opposite joint line

Test hand- grasping the heel to maintain and control tibial rotation

Action performed- beginning with the knee in full flexion, medially and laterally rotate the tibia and note any pain or audible click. The, with the tibia laterally rotated, extend the knee beyond 90° while maintaining lateral tibial rotation to stress the medial meniscus. To stress the lateral meniscus, reposition the leg into full flexion and medially rotate the tibia before moving it into extension

Positive result- audible click or joint line pain

Apley Distraction/Compression Test

Assesses- integrity of meniscus of knee or ligaments

Patient position- prone with knee passively flexed to 90° and thigh stabilized with clinicians knee or stabilizing hand

Clinician position- standing at patient's side

Stable hand- Assisting test hand or on posterior distal thigh (distraction)

Test hand- Around ankle or on plantar foot

Action performed- Rotate the tibia medially and laterally while applying traction to the knee. Repeat rotational movements while applying compression to the knee joint

Positive result- Pain with distraction : ligamentous pathology; Pain with compression; meniscal pathology

Quad strain

MOI- muscle overloaded during sudden acceleration or deceleration (sprinting, kicking, and weightlifting)

S/S- immediate pain, spasm, and loss of function.

with 1° strains- initial pain quickly subsides and athletes returns to activity only to have pain return and remain the next day

-pain with passive stretch into knee flexion with the hip extended

-pain and weakness with active or resistive extension are consistent with the degree of injury

- palpable tender over injured area, and a defect may exist with 2nd and 3rd ° injuries

2nd and 3rd ° may also result in observable swelling, ecchymosis and quad avoidance gait

Hamstring strain

more common than quad strains

MOI- most often with sprinting activities

- when quad is forcefully contracted while the hamstrings eccentrically contract

- asynchronous muscle timing, inflexibility, and muscular imbalance may be contributing factors

S/S- sharp or burning pain in the hamstrings at the time of injury

some 1st° pain and stiffness may be delayed until the next day

- palpable tenderness and spasm over and around the injured fibers

- pain with passive stretch and active or resisted knee flexion

- may have palpable defect (2nd and 3rd °) and delayed swelling and ecchymosis over back of thigh

- exhibit shortened stride during gait on involved side

Patellar Tendon rupture

MOI- violent, rapid quad contraction

can occur from acute single mechanism but more often tear is precipitated by episodes of chronic tendinitis or inflammation that weaken the structure

S/S- immediate, severe pain and loss of active knee extension

- pop may be fle tand heard as tendon ruptures

- patella appears to sit more superiorly with an infrapatellar tendon rupture, palpable gap between inferior pole of patella and tibial tuberosity

- with suprapatellar the defect is superior to the patella

- considerable swelling and ecchymosis will likely result within 24 hours following injury

Plica Syndrome

- an anomaly or fold in the synovial membrane on the anterior aspect of the knee that runs from the lateral femoral condyle, superior and medial to patella, and down toward the fat pad

- most typical location is along superior medial border of patella

- often asymptomatic

- if area becomes inflamed or taut= snapping, clicking, or jumping of the patella as knee moves into flexion

S/S- pain along the medial border of the patella, swelling, and a locking sensation

Popliteal Cyst (Baker's Cyst)

MOI- results from a herniation of the synovial cavity and fluid accumulation in the popliteal space

S/S- palpable, fluid-filled cyst in the inferomedial popliteal fossa

may not be tender and typically does not restrict movement

* commonly associated with meniscal tears and arthritic conditions and so should suspect intra-articular pathology when patient presents with this as primary complaint

Bursitis

MOI- repetitive trauma or friction over bursa

- suprapatellar, prepatellar, and superficial infrapatellar bursae= irritated with frequent kneeling or bending

- pes anserine bursitis= caused by overuse and repetitive valgus loading (distance runners and cyclists)

S/S- pain, redness, and localized swelling

- area is TTP and warm to touch

- crepitus and bogginess or thickening of bursal fluid also occurs

- knee flexion may be painful or limited with patellar bursitis secondary to increased pressure over bursa as skin tightens into flexion

- extension may also be limited with suprapatellar and deep infrapatellar bursal swelling

- pes anserine bursitis is painful with knee flexion and extension and medial tibial rotation

Patellar Tendinitis (Jumper's Knee)

MOI- repetitive jumping, running, or weightlifting

overloading the extensor mechanism can cause microtearing and inflammation of either the suprapatellar or infrapatellar tendons

S/S- pain, inflammation, and mild swelling either superior or inferior to patella

- palpable tenderness and crepitus often present over inflamed tendon

- pain with passive stretching of tendon and active or resisted knee extension

Iliotibial Band Friction Syndrome

MOI- overuse mostly seen in runners and cyclists, excessive friction between IT band an the lateral femoral epicondyle (between 25-30° of knee flexion)

- patients with genu valgum, excessive quad angle, excessive pronation, or leg length discrepancy are more prone than others

tightness of IT band, training errors, downhill running and running on a slanted surface may also be predisposing factors

S/S- pain and point tenderness over the lateral femoral condyle just proximal to lateral joint line

pain may also radiate up the lateral thigh or down the IT band insertion (Gerdy's tubercle)

Noble Compression test

Assesses- IT band friction syndrome

Patient position- Supine with knee passively flexed to 90° and hip flexed to at least 45°

Clinician position- standing at patient's side

Stable hand- At patient's foot to control knee motion

Test hand- Over IT band just proximal to lateral femoral condyle

Action performed- Knee is passively or actively extended

Positive result- Pain occurs at 30° from full extension

Hamstring Tendinopathy

MOI- repetitive and pressure over the tendon and tuberosity (cycling with an improperly adjusted seat or from overstretching or tensioning of the proximal attachment with straight leg hip flexion ) or repetitive flexion and overuse during running and weightlifting

S/S- proximal= achy pain just below the gluteal fold and deep palpable tenderness just distal to the ischial tuberosity

- passive stretching in a straight knee hip flexion, resisted straight knee hip extension, and long striding exacerbate the pain

distal= insidious onset of pain, palpable tenderness, mild swelling, and crepitus

Pes Anserine Tendinopathy

S/S- anteroinferior medial knee pain, TTP over the anteromedial tibial plateau, crepitus, and local swelling

- pain with active knee flexion, passive knee extension, and possibly valgus stress

Epiphyseal Fractures

MOI- rotational and shearing forces at the knee joint. Twisting, varus, or valgus forces directly at the knee with foot firmly planted are common in adolescents

S/S- immediate pain, tenderness along bone, swelling, loss of function, possible deformity

- may report hearing a pop or snap at the joint

- may observe crepitus with joint motion, but will be unwilling to move the extremity

- false joint motion or opening of the epiphyseal joint wit varus and valgus testing, may make it difficult to distinguish an epiphyseal fracture from collateral ligament injury

potential complication is disruption and premature closing of the growth plate which may result in true leg length diff

Tibial Plateau Fracture

MOI- severe varus, valgus, or rotational forces in combination with axial compression when the foot is firmly planted

S/S- severe and immediate pain and is unwilling to move the knee joint

- swelling, tenderness over proximal tibia, pain with percussion, crepitus, and possibly deformity

Patella Fracture

MOI- direct contact (fall directly on patella with knee flexed) or from indirect forces (severe tractioning produced by forceful quad contraction)

S/S- sudden and severe pain in the kneecap and is unwilling to contract the quad or extent the knee or is unable to do so without considerable pain

- immediate tenderness, rapid swelling, and crepitus over patella

- can cause considerable and prolonged disability

Femur Fracture

MOI- severe, direct blow to the midthigh or secondary to severe torsional forces

S/S- immediate and severe pain, muscle spasm, inability to move extremity

- considerable hemorrhage may occur resulting in shock

- shortened, laterally rotated thigh= characteristic deformity

Chondral and Osteochondral Fractures

MOI- Joint compression combined with varus, valgus, or rotational shearing force can contuse the articular surface and cause a compression or avulsion fracture resulting in loose fragments that produce irritation and locking + clicking in the joint

S/S- pain, immediate or delayed swelling, locking or clicking, and pain with joint compression or weight bearing

Patellofemoral Subluxation and Dislocation

MOI- direct blow to medial patella and indirect forces applied by quads during cutting maneuvers with the tibia laterally rotated can force the patella to displace over the lateral femoral condyle

- abnormally shallow femoral groove, excessive Q angle, hypermobile patella, weak medial quads, or patella alta= more prone to recurrent patellar dislocations

S/S- sharp pain and pop in anterior knee and feeling of knee giving way at time of injury

if spontaneously reduces= palpable tenderess along medial border of patella and soft tissue structures. Lateral femoral condyle may also be tender

- considerable anterior knee swelling shortly after (esp with 1st time)

Patellar Apprehension Test

Assesses- Patellar dislocation

Patient position- Supine with lower extremity relaxed in 20-30° of knee flexion

Clinician position- standing at patient's side

Stable hand- Used with test hand

Test hand- Thumbs over medial patella with fingers lying across and over distal lateral thigh and proximal tibia, superior and inferior to knee joint

Action performed- Apply lateral force slowly to glide patella laterally

Positive result- Patient prevents maneuver by reactively contracting quad or stops test for fear of patella dislocating

Tibiofemoral Dislocation

MOI- large mechanical forces that force the joint well beyond its normal ROM

- significant ligament damage + neurovascular implications

Patellofemoral Pain Syndrome

anterior knee pain

MOI- variety of factors that result in patellar malalignment, increased patellofemoral compression, or poor patellofemoral tracking

- subtalar pronation, lateral tibial torsion, genu valgum, increased Q angle, hip anteversion, increased anterior pelvis tilt, patella alta

- weak in vastus medialis relative to lateral quads and tightness in lateral retinaculum and IT band

- an abrupt change in training activity, surface, intensity, or duraction that substantially increased load on patellofemoral joint

S/S- poorly localized anterior knee pain that is exacerbated by squatting, climbing stairs, kneeling, ambulating, or other acitivite after prolonged sitting (Theater sign)

- little or no swelling

- pain appears gradually

Active Lateral Glide Test

Assesses- Tightness of lateral thigh structures or quads muscle imbalances

Patient position- Supine with knee in extension and thigh muscles relaxed

Alternative position in WB: straddle squat, with involved extremity forward

Clinician position- standing by patient, observing patella

Stable hand- Not involved, active test

Test hand- Not involved, active test

Action performed- Observe the movement of the patella as the patient contracts the quads

Positive result- Excessive lateral versus superior movement of patella

Chondromalacia Patella

MOI- direct and repetitive trauma, patellar malalignment, or previous trauma such as patella dislocation or a fracture that extends through the articular surface

S/S- general anterior knee pain, crepitus, minor swelling, and increased pain with patellofemoral compression in activities such as deeply bending the knee, extending the knee, or walking up and down stairs

- note palpable tenderness under the medial and lateral border of the patella

Patellar Grind Test

can have a positive result in healthy knees if done incorrectly

Assesses- Integrity of patellofemoral joint articulating surface

Patient position- Supine with thigh relaxed and knee in full extension

Clinician position- standing at patient's side

Stable hand- not used

Test hand- The web space of the hand is applied just proximal to the superior pole of the patella

Action performed- Push down on the thigh and instruct the patient to contract the quad

Positive result- Pain with quad contraction

Osteoarthritis

MOI- articular cartilage surface degenerates over time

- systemic factors like family history, sex (female), age (older), nutrition, obesity, and repetitive stress occupations (eg. military) can influence susceptibility

- athletes sustaining a traumatic knee injury are at substantial risk for early OA development

S/S- joint pain, stiffness, decreased joint ROM, quad weakness

- may complain of grating sensation when joint is moved

Apophysitis (Osgood-Schlatter Disease)

MOI- repetitive tractioning by the patellar tendon in young athletes leading to irritation, inflammation, and partial avulsion

S/S- focused anterior knee pain, swelling, tenderness over tibial tuberosity and increased prominence of tibial tuberosity

- increased pain with knee extension exercises, squatting, kneeling, and jumping

Osteochondritis Dissecans

MOI- cause is unknown but may be repetitive insult

S/S- gradual onset of pain and periodic swelling after activity

- may complain of occasional clicking or catching in the joint if there is a loose fragment

- palpable tenderness may be present on the femoral condyle near the joint line

Wilson Test

Assesses- Presence of osteochondritis dissecans of medial femoral condyle

Patient position- Sitting with legs over end of the table

Clinician position- Seating in front of patient and off to side, observing test results

Stable hand- Not involved, active test

Test hand- Not involved, active test

Action performed- Patient actively extends the knee with the tibia in medial rotation

Positive result- Pain in knee about 30° from extension. Pain resolved when motion is repeated with the tibia laterally rotated

Peroneal Nerve Palsy

MOI- trauma secondary to direct blow (contusion) severe cold(ice bag application), or tractioning (varus force)

S/S- pain and tenderness over distal fibula, numbness, burning, or tingling along the lateral aspect of the leg and into the dorsum of the foot and motor weakness of the dorsiflexors, evertors, and toe extensors

- foot drop may appear immediately with severe trauma or may appear progressively over the next day secondary to delayed swelling

Popliteal Artery or Nerve Injury

MOI- severe fracture of total knee dislocation