© 2011 McGraw-Hill Higher Education. All rights reserved. Chapter 20: The Knee and Related Structures.

© 2011 McGraw-Hill Higher Education. All rights reserved.

Chapter 20: The Knee and Related Structures

• One of the most traumatized joint in the physically active population

• Hinge joint w/ a rotational component

• Stability is due primarily to ligaments, joint capsule and muscles surrounding the joint

• Designed for stability w/ weight bearing and mobility in locomotion


Anatomy- Bones

• Femur- aka the thigh bone, articulates with the tibia

• Tibia- shin bone, groves in which femur condyles articulate with

• Fibula- rotational movement

• Patella- largest sesmoid bine, located in the tendon of the quadricep

Figure 20-1© 2011 McGraw-Hill Higher Education. All rights

reserved.

Menisci

• Two oval fibrocartilages– Deepens the articular facets– Cushions any stresses– Maintains spaces between the femoral

condyles and the tibial plateau– Stabilizes the knee at 90 degrees (medial)

• Medial Meniscus: C-shaped

• Lateral Meniscus: O-shaped

• Meniscal Blood Supply: three zones– Red- Red: outer zone and good vascular

supply– Red-White: middle third, minimal blood

supply– White- White: inner third, avascular

Figure 20-2


Stabilizing Ligaments• Anterior Cruciate Ligament: (ACL) starts

in the anterior portion of the tibia back to the lateral condyle of the femur– Three twitsted bands– Prevents femur from moving posteriorly in

weight bearing and tibia moving anteriorly in non weight bearing

– Stabilizes tibia from internal rotation– Works with the hamstrings

• Posterior Cruciate Ligament: (PCL) stronger of two, back of the tibia to the front of the medial femoral condyle– Resists internal rotation of tibia– Prevents hyperextenstion of the knee– Limits anterior movement of femur in

weight bearing and posterior movement of tibia in non weight bearing

• Medial Collateral Ligaments: (MCL) includes both superficial and deep– Attaches above the joint line on the medial

epicondyle of the femur and below on the tibia

– Keeps knee from Valgus and external roation

• Lateral Collateral Ligament (LCL) – fibrous cord about the size of a pencil– Attaches to the lateral epicondyle of the

femur and the head of the fibula– Keeps knee from Varus movement

Figure 20-3 A-B


Figure 20-3 Capsule Ligaments


Joint Capsule

• Knee joint is enveloped by a the largest joint capsule

• Reinforced by collateral ligaments and muscle

Figure 20-4


Knee Musculature

• Knee Flexion: bicep femoris, semitendinosus, semimembranosus, gracilis, sartorius, gastrocnemius, popliteus, and plantaris

• Knee Extension: (Quad) vastus medialis oblique, vastus lateralis, vastus intermedius and rectus femoris

• External Rotation: bicep femoris (knee moves into extension)

• Internal Rotation: popliteal, semitendinosus, semimembranosus, sartorius and gracilis (knee moves into flexed)

• Iliotibial Band (IT Band): dynamic lateral stabilizer

Figure 20-5 A & B© 2011 McGraw-Hill Higher Education. All rights

reserved.

Figure 20-5C© 2011 McGraw-Hill Higher Education. All rights

reserved.

Bursae

• Synovial tissue sac to reduce the friction between structures

• Over 2 dozen in the knee joint

Fat Pads

• Several around the knee

• Infrapatellar in largest in the knee

Nerve Supply

• Tibial Nerve: innervates the hamstring and gastocnemius

• Common Peroneal Nerve: Innervates the short headof the bicep femoris, wraps around fibula head (prone to injury)

• Femoral Nerve: innervates the quadriceps and sartorius

Figure 20-6


Blood Supply

• Popliteal fossa which stems from the femoral artery– Breaks into four brances

Figure 20-7


Functional Anatomy• Movement of the knee requires

flexion, extension, rotation and the arthrokinematic motions of rolling and gliding

• Rotational component involves the “screw home mechanism”– As the knee extends it externally rotates

because the medial femoral condyle is larger than the lateral

– Provides increased stability to the knee– Popliteus “unlocks” knee allowing knee to

flex© 2011 McGraw-Hill Higher Education. All rights

reserved.

• Capsular ligaments are taut during full extension and relaxed w/ flexion– Allows rotation to occur

• Deeper capsular ligaments remain taut to keep rotation in check

• PCL prevents excessive internal rotation, limits anterior translation and posterior translation when tibia is fixed and non-weight bearing, respectively

• ACL stops excessive internal rotation, stabilizes the knee in full extension and prevents hyperextension


• Range of motion includes 140 degrees of motion– Limited by shortened position of

hamstrings, bulk of hamstrings and extensibility of quads

• Patella aids knee during extension, providing a mechanical advantage– Distributes compressive stress on the

femur by increasing contact between patellar tendon and femur

– Protects patellar tendon against friction– When moving from extension to flexion

the patella glides laterally and further into trochlear groove


• Kinetic Chain– Directly affected by motions and

forces occurring at the foot, ankle, lower leg, thigh, hip, pelvis, and spine

– With the kinetic chain forces must be absorbed and distributed

– If body is unable to manage forces, breakdown to the system occurs

– Knee is very susceptible to injury resulting from absorption of forces


Assessing the Knee Joint• Determining the mechanism of

injury is critical• History- Current Injury pg 563

– Past history– Mechanism- what position was your body

in?– Did the knee collapse?– Did you hear or feel anything? (pop)– Could you move your knee immediately

after injury or was it locked?– Did swelling occur? (sudden or gradual)– Where was the pain (local or diffuse)


• History - Recurrent or Chronic Injury– What is your major complaint?– When did you first notice the condition?– Is there recurrent swelling?– Does the knee lock or catch?– Is there severe pain?– Grinding or grating?– Does it ever feel like giving way?– What does it feel like when ascending

and descending stairs?– What past treatment have you

undergone?


• Observation– Walking, half squatting, going up and

down stairs– Swelling, ecchymosis,– Leg alignment

• Genu valgum and genu varum• Hyperextension and hyperflexion• Patella alta and baja• Patella rotated inward or outward

– May cause a combination of problems

• Tibial torsion, femoral anteversion and retroversion


Leg Alignment• Genu Valgum: knocked knee

– Pronated feet– Increase tension on medial ligaments,

compression on lateral surface

• Genu Varum: bowlegs– Structural: Deviation of the femur and tibia– Functional: Associated with hyperextended knees

• Genu Recurvatum: Hyperextended knees– Compensation of lordosis or swayback– Weakness of the hamstring

Figure 20-14


Genu Recurvatum

Patella Malalignment

• Patella Alta: patella in a more superior position when standing– The patella tendon to patella ratio is

greater than 1:1; usually greater than 20%

• Patella Baja: sets in a more inferior position – Less than a 1:1 ratio

Measuring Alignment

• Tibial Torsion: Have the patient kneel on a stool with the foot relaxed– Dissect center of the thigh and the lower

leg– Another line between the heel and the foot

• Tibial torsion– An angle that

measures less than 15 degrees is an indication of tibial torsion

• Femoral Anteversion and Retroversion– Total rotation of the

hip equals ~100 degrees

– If the hip rotates >70 degrees internally, anteversion of the hip may exist

Figure 20-9


Patella Orientation

• Position of the patella relative to the tibia with the patient supine

• Glide: deviated laterally or medially• Patellar Tilt: height of the medial to the

lateral border of the patella• Patellar Rotation: Line of the inferior

pole of patella to the femur• Anteroposterior Tilt: Laterally

Glide Component & Tilt Component

Figure 20-12 & 13 © 2011 McGraw-Hill Higher Education. All rights

reserved.

Knee Symmetry or Asymmetry• Do the knees look symmetrical? Is there

obvious swelling? Atrophy?


Leg Length• Anatomical: Measured from the ASIS to the

lateral malleolus– Anatomical differences can potentially cause

problems in all weight bearing joints

• Functional: Measured from Umbilicus to medial malleolus– Functional differences can be caused by

pelvic rotations or mal-alignment of the spine

Observation Lab

• Leg Alignment

• Patella Malalignment

• Tibial Alignment

• Patella Orientation

• Leg Length

Palpation - Bony

• Medial tibial plateau• Medial femoral

condyle• Adductor tubercle• Gerdy’s tubercle• Lateral tibial plateau• Lateral femoral

condyle• Lateral epicondyle• Medial epicondyle

• Head of fibula• Tibial tuberosity• Patella• Superior and inferior

patella borders (base and apex)

• Around the periphery of the knee relaxed, in full flexion and extension


•Palpation - Soft Tissue• Vastus medialis• Vastus lateralis• Rectus femoris• Quadriceps and

patellar tendon• Sartorius• Medial patellar plica• Anterior joint capsule• Iliotibial Band• Arcuate complex

• Medial and lateral collateral ligaments

• Pes anserine• Medial/lateral joint

capsule• Semitendinosus• Semimembranosus• Gastrocnemius• Popliteus• Biceps Femoris


Palpation of Swelling• Intra vs. extracapsular swelling• Intracapsular may be referred to as joint

effusion– Swelling w/in the joint that is caused by

synovial fluid and blood is a hemarthrosis– Sweep maneuver- moving swelling from one

side to another– Ballotable patella - sign of joint effusion

• Extracapsular swelling tends to localize over the injured structure – May ultimately migrate down to foot

and ankle

Special Tests

• Special Tests for Knee Instability– Use endpoint feel to determine stability– MRI may also be necessary for assessment– Classification of Joint Instability

• Knee laxity includes both straight and rotary instability

• Translation (tibial translation) refers to the glide of tibial plateau relative to the femoral condyles

• As the damage to stabilization structures increases, laxity and translation also increase


– Collateral Ligament Stress Tests (Valgus and Varus)• Used to assess the

integrity of the MCL and LCL respectively

• Testing at 0 degrees incorporates capsular testing while testing at 30 degrees of flexion isolates the ligaments

• Hands at ankle and head joint line


– Anterior Cruciate Ligament Tests• Drawer test at 90 degrees of flexion

– Tibia sliding forward from under the femur is considered a positive sign (ACL)

– Should be performed w/ knee internally and externally to test integrity of joint capsule

Figure 20-18


• Lachman Drawer Test– Will not force knee

into painful flexion immediately after injury

– Reduces hamstring involvement

– At 30 degrees of flexion an attempt is made to translate the tibia anteriorly on the femur

– A positive test indicates damage to the ACL

Figure 20-19© 2011 McGraw-Hill Higher Education. All rights

reserved.

• A series of variations are also available for the Lachman Drawer Test– May be necessary if athlete is large or

examiner’s hands are small– Variations include

• Rolled towel under the femur• Leg off the table approach with athlete supine• Athlete prone on table with knee and lower leg

just off table


• Pivot Shift Test– Used to determine

anterolateral rotary instability– Position starts w/ knee

extended and leg internally rotated

– The thigh and knee are then flexed w/ a valgus stress applied to the knee

– Reduction of the tibial plateau (producing a clunk) is a positive sign

– Slocum’s test is variation on the pivot shift


Figure 20-20

• Jerk Test– Reverses direction of the pivot shift– Moves from position of flexion to

extension– W/out an ACL the tibia will sublux at

20 degrees of flexion


Figure 20-21

• Flexion-Rotation Drawer Test– Knee is taken from a position of 15

degrees of flexion (tibia is subluxed anteriorly w/ femur externally rotated)

– Knee is moved into 30 degrees of flexion where tibia rotates posteriorly and femur internally rotates


Figure 20-22

• Losee’s Test– Similar to flexion-

reduction drawer test– Performed side-lying– Begins with knee at 45

degrees of flexion and external tibial rotation

– Knee is subluxed anteriorly

– As the knee is extended it reduces


Figure 20-22

KNEE SPECIAL TEST LAB PART I

• VALGUS

• VARUSDRAWER TESTLACHMAN DRAWERPIVOT-SHIFT

Posterior Cruciate Ligament Tests

• Page 572 and 573

• Posterior Cruciate Ligament Tests– Posterior Drawer Test

• Knee is flexed at 90 degrees and a posterior force is applied to determine translation posteriorly

• Positive sign indicates a PCL deficient knee

– External Rotation Recurvatum Test• With the athlete supine, the leg is lifted by

the great toe• If the tibia externally rotates and slides

posteriorly there may be a PCL injury and damage to the posterolateral corner of the capsule


• Posterior Sag Test (Godfrey’s test)– Athlete is

supine w/ both knees flexed to 90 degrees

– Lateral observation is required to determine extent of posterior sag while comparing bilaterally

Figure 20-25


•Instrument Assessment of the Cruciate Ligaments

• A number of devices are available to quantify AP displacement of the knee

• KT-2000 arthrometer, Stryker knee laxity tester and Genucom can be used to assess the knee

• Test can be taken pre & post-operatively and throughout rehabilitation

Figure 20-26


• Meniscal Tests– McMurray’s Meniscal Test

• Used to determine displaceable meniscal tear

• Leg is moved into flexion and extension while knee is internally and externally rotated in conjunction w/ valgus and varus stressing

• A positive test is found when clicking and popping are felt


Figure 20-27


• Apley’s Compression Test– Hard downward pressure

is applied w/ rotation– Pain indicates a meniscal

injury

• Apley’s Distraction Test– Traction is applied w/

rotation– Pain will occur if there is

damage to the capsule or ligaments

– No pain will occur if it is meniscal


• Thessaly Test– Patient stands on one leg – Tested with knee flexed to

5 degrees and 20 degrees– Patient then rotates trunk

and knee into internal and external rotation, with clinician supporting patient

– Positive test results in pain along medial or lateral joint line

– Perform test on healthy side first for comparison


Figure 20-29

KNEE SPECIAL TEST LAB PART II

• POSTERIOR DRAWEREXTERNAL ROTATION RECURVATUM

• POSTERIOR SAG (GODFREY’S)

• MCMURRAY’S MENISCAL

• APLEY COMPRESSION

• Girth Measurements– Changes in girth can occur due to

atrophy, swelling and conditioning– Must use circumferential measures to

determine deficits and gains during the rehabilitation process

– Measurements should be taken at the joint line, the level of the tibial tubercle, belly of the gastrocnemius, 2 cm above the superior border of the patella, and 8-10 cm above the joint line

• Subjective Rating– Used to determine patient’s perception

of pain, stability and functional performance


Patellar Examination

• Palpation of the Patella– Must palpate around and under patella

to determine points of pain

• Patella Grinding, Compression and Apprehension Tests– A series of glides and compressions are

performed w/ the patella to determine integrity of patellar cartilage


• Q-Angle– Lines which bisect the patella relative to the

ASIS and the tibial tubercle– Normal angle is 10 degrees for males and

15 degrees for females– Elevated angles often lead to pathological

conditions associated w/ improper patella tracking

• The A - Angle– Patellar orientation to the tibial tubercle– Quantitative measure of the patellar

realignment after rehabilitation– An angle greater than 35 degrees is often

correlated w/ patellofemoral pathomechanics


FIGURE 20-32A, Measuring the Q angle of the knee. B, Determining the A angle.

Patellar Compression, Patellar Grinding, & Apprehension

• Grind: knee at 20 degrees flexion- patella moved forward and back

• Grind: knee flexed, patella forced forward, patient contracts and extends knee

• Apprehension: for subluxed or dislocated, patella forced laterally


• Patella Grinding, Compression and Apprehension Tests

• Functional Examination– Must assess walking, running, turning

and cutting

– Co-contraction test, vertical jump, single leg hop tests and the duck walk

– Resistive strength testing

– Tests should be performed at speed w/out limping or favoring injured limb

– Use baseline for comparison if available


Prevention of Knee Injuries• Physical Conditioning and Rehabilitation

– Total body conditioning is required•Strength, flexibility, cardiovascular and

muscular endurance, agility, speed and balance

– Muscles around joint must be conditioned (flexibility and strength) to maximize stability

– Must avoid abnormal muscle action through flexibility

– In an effort to prevent injury, extensibility of hamstrings, erector spinae, groin, quadriceps and gastrocnemius is important

– Hamstring strength approx 60-70% of quad© 2011 McGraw-Hill Higher Education. All rights

reserved.

• Decreasing the Risk for ACL Injury– Focus on strength, neuromuscular

control, balance– Series of different programs which

address balance board training, landing strategies, plyometric training, and single leg performance

– Can be implemented in rehabilitation and preventative training programs

• Shoe Type– Change in football footwear has

drastically reduced the incidence of knee injuries

– Shoes w/ more short cleats does not allow foot to become fixed - still allows for control w/ running and cutting© 2011 McGraw-Hill Higher Education. All rights

reserved.

• Functional and Prophylactic Knee Braces– Used to prevent and

reduce severity of knee injuries

– Used to protect MCL, or prevent further damage to grade 1 & 2 sprains of the ACL or to protect the ACL following surgery

– Can be custom molded and designed to control rotational forces


Figure 20-37

The Knee and Related StructuresPart II

Recognition and Management of Specific

Injuries• Medial Collateral Ligament Sprain

– Etiology• Result of severe blow from lateral side

(valgus force)– Signs and Symptoms - Grade I

• Little fiber tearing or stretching• Stable valgus test• Little or no joint effusion• Some joint stiffness and point tenderness

on lateral aspect• Relatively normal ROM


– Management• RICE for at least 24

hours• Crutches if necessary• Follow-up care will

include cryokinetics w/ exercise

• Move from isometrics and STLR exercises to bicycle riding and isokinetics

• Return to play when all areas have returned to normal

• May require 3 weeks to recover

Figure 20-38


– Signs and Symptoms (Grade II)• Complete tear of deep capsular ligament and partial

tear of superficial layer of MCL• No gross instability; laxity at 5-15 degrees of flexion• Slight swelling• Moderate to severe joint tightness w/ decreased ROM• Pain along medial aspect of knee

– Management• RICE for 48-72 hours; crutch use until acute phase

has resolved• Possibly a brace or casting prior to the initiation of

ROM activities• Modalities 2-3 times daily for pain• Gradual progression from isometrics (quad exercises)

to CKC exercises; functional progression activities



Grade 1 Grade 2

Grade 3

– Signs and Symptoms (Grade III)• Complete tear of supporting ligaments• Complete loss of medial stability• Minimum to moderate swelling• Immediate pain followed by ache• Loss of motion due to effusion and hamstring

guarding• Positive valgus stress test

– Management• RICE• Conservative non-operative versus

surgical approach– Limited immobilization (w/ a brace);

progressive weight bearing and increased ROM over 4-6 week period• Rehab would be similar to Grade I & II

injuries© 2011 McGraw-Hill Higher Education. All rights

reserved.

Lateral Collateral Ligament Sprain

• Page 581

• Lateral Collateral Ligament Sprain

– Etiology• Result of a varus force,

generally w/ the tibia internally rotated

• If severe enough damage can also occur to the cruciate ligaments, ITB, and meniscus, producing bony fragments as well


Figure 20-41

• Lateral Collateral Ligament Sprain– Signs and Symptoms

• Pain and tenderness over LCL• Swelling and effusion around the LCL• Joint laxity w/ varus testing• May cause irritation of the peroneal

nerve

– Management– Follows management of MCL injuries

depending on severity


• Anterior Cruciate Ligament Sprain– Etiology

• MOI - tibia externally rotated and valgus force at the knee (occasionally the result of hyperextension from direct blow) plant and twist

• May be linked to inability to decelerate valgus and rotational stresses - landing strategies

Male versus female• Research is quite extensive in regards to

impact of femoral notch, ACL size and laxity, malalignments (Q-angle) & faulty biomechanics

• Extrinsic factors may include, conditioning, skill acquisition, playing style, equipment, preparation time

• May also involve damage to other structures including meniscus, capsule, and MCL


• Signs and Symptoms– Experience pop w/ severe

pain and disability– Positive anterior drawer

and Lachman’s – Rapid swelling at the joint

line– Other ACL tests may also

be positive


Figure 20-42

• Management– RICE; use of crutches– Arthroscopy may be necessary to determine

extent of injury– Could lead to major instability in incidence

of high performance– W/out surgery joint degeneration may result– Age and activity may factor into surgical

option– Surgery may involve joint reconstruction w/

grafts (tendon), transplantation of external structures•Will require brief hospital stay and 3-5

weeks of a brace•Also requires 4-6 months of rehab


Posterior Cruciate Ligament Sprain

• Page 584

• Posterior Cruciate Ligament Sprain– Etiology

• Most at risk during 90 degrees of flexion

• Fall on bent knee is most common mechanism

• Can also be damaged as a result of a rotational force

• Sometimes referred to as a “dashboard injury”

– May result when flexed knee of car driver or passenger hits the dashboard


Figure 20-43

– Signs and Symptoms• Feel a pop in the back of the knee• Tenderness and relatively little

swelling in the popliteal fossa• Laxity w/ posterior sag test

– Management• RICE• Non-operative rehab of grade I and II

injuries should focus on quad strength• Surgical versus non-operative

– Surgery will require 6 weeks of immobilization in extension w/ full weight bearing on crutches

– ROM after 6 weeks and PRE at 4 months


• Meniscal Lesions– Etiology

• Medial meniscus is more commonly injured due to ligamentous attachments and decreased mobility

– Also more prone to disruption through torsional and valgus forces

• Most common MOI is rotary force w/ knee flexed or extended

• Tears may be longitudinal, oblique or transverse


Figure 20-44

– Signs and Symptoms• Effusion developing over 48-72 hour

period• Joint line pain and loss of motion• Intermittent locking and giving way• Pain w/ squatting• Portions may become detached causing

locking, giving way or catching w/in the joint

• If chronic, recurrent swelling or muscle atrophy may occur


– Management• If the knee is not locked, but indications

of a tear are present further diagnostic testing may be required

• If locking occurs, anesthesia may be necessary to unlock the joint w/ possible arthroscopic surgery follow-up

• W/ surgery all efforts are made to preserve the meniscus -- with full healing being dependent on location

• Meniscectomy rehab allows partial weight bearing and quick return to activity

• Repaired meniscus will require immobilization and a gradual return to activity over the course of 12 weeks


Knee Plica

• Page 586

• Knee Plica– Etiology

•Irritation of the plica (generally, mediopatellar plica and often associated w/ chondromalacia)

– Signs and Symptoms•Possible history of knee pain/injury•Recurrent episodes of painful

pseudo-locking•Possible snapping and popping•Pain w/ stairs and squatting•Little or no swelling, and no

ligamentous laxity


• Management– Treat

conservatively w/ RICE and NSAID’s if the result of trauma

– Recurrent conditions may require surgery


Figure 20-45

Medial Patellar Plica

• Osteochondral Knee Fractures– Etiology

• Same MOI as collateral/cruciate ligaments or meniscal injuries

• Twisting, sudden cutting or direct blow• Fractures of cartilage and underlying bone

varying in size and depth

– Signs and Symptoms• Hear a snap and feeling of giving way• Immediate swelling and considerable pain• Diffuse, pain along joint line


– Management• Diagnosed through use of CT and MRI• Treatment dependent on stability of fracture• If stable the patient will be casted• If fragment is loose surgical reattachment will

occur or removal via arthroscopic• Microfracture procedures used to repair

defects in underlying bone– Generates small amounts of bleeding to

stimulate bone growth and healing• Rehabilitation is dependent on location of

fracture• ROM is typically initiated early after surgery

with active strengthening beginning after 6 weeks

• Return to activity at 3-6 months


• Osteochondritis Dissecans– Etiology

• Partial or complete separation of articular cartilage and subchondral bone

• Cause is unknown but may include blunt trauma, possible skeletal or endocrine abnormalities, prominent tibial spine impinging on medial femoral condyle, or impingement due to patellar facet


– Signs and Symptoms• Aching pain with recurrent swelling and

possible locking• Possible quadriceps atrophy and point

tenderness

– Management• Rest and immobilization for children• Surgery may be necessary in teenagers

and adults (drilling to stimulate healing, pinning or bone grafts)


Joint Contusion

• Page 588

• Joint Contusions– Etiology

• Blow to the muscles crossing the joint (vastus medialis)

– Signs and Symptoms• Present as knee sprain, severe pain, loss of

movement and signs of acute inflammation• Swelling, discoloration• Possible capsular damage

– Management• RICE initially and continue if swelling persists• Gradual progression to normal activity

following return of ROM and padding for protection

• If swelling does not resolve w/in a week a chronic condition (synovitis or bursitis) may exist requiring more rest


• Peroneal Nerve Contusion– Etiology

• Compression of peroneal nerve due to a direct blow by the neck of the fibula

– Signs and Symptoms• Local pain and possible shooting nerve pain• Numbness and paresthesia in cutaneous distribution of

the nerve• Added pressure may exacerbate condition• Generally resolves quickly -- in the event it does not

resolve, it could result in drop foot

– Management• RICE and return to play once symptoms resolve and no

weakness is present• Padding for fibular head is necessary for a few weeks


• Bursitis– Etiology

• Acute, chronic or recurrent swelling• Prepatellar = continued kneeling• Infrapatellar = overuse of patellar tendon

– Signs and Symptoms• Prepatellar bursitis may be localized swelling

above knee that is ballotable• Swelling in popliteal fossa may indicate a

Baker’s cyst– Associated w/ semimembranosus bursa or

medial head of gastrocnemius– Commonly painless and causing little disability– May progress and should be treated

accordingly

– Management• Eliminate cause, RICE and NSAID’s• Aspiration and steroid injection if chronic

© 2011 McGraw-Hill Higher Education. All rights

reserved.

Figure 20-47


• Patellar Fracture– Etiology

• Direct or indirect trauma (severe pull of tendon)

• Semi-flexed position with forcible contraction (falling, jumping or running)

– Signs and Symptoms• Hemorrhaging and joint effusion w/

generalized swelling• Indirect fractures may cause capsular

tearing, separation of bone fragments and possible quadriceps tendon tearing

• Little bone separation w/ direct injury

– Management• X-ray necessary for confirmation of

findings• RICE and splinting if fracture suspected• Refer and immobilize for 2-3 months


Figure 20-47

Acute Patella Subluxation or Dislocation

• Page 589


• Acute Patella Subluxation or Dislocation– Etiology

• Deceleration w/ simultaneous cutting in opposite direction (valgus force at knee)

• Quad pulls the patella out of alignment

• Some individuals may be predisposed

• Repetitive subluxation will stress medial restraints

– Signs and Symptoms• W/ subluxation, pain and swelling,

restricted ROM, palpable tenderness over adductor tubercle

• Results in total loss of function© 2011 McGraw-Hill Higher Education. All rights

reserved.

Figure 20-49

– Management• Reduction is performed by flexing hip,

moving patella medially and slowly extending the knee

• Following reduction, immobilization for at least 4 weeks w/ use of crutches and isometric exercises during this period

• After immobilization period, horseshoe pad w/ elastic wrap should be used to support patella

• Muscle rehab focusing on muscle around the knee, thigh and hip are key (STLR’s are optimal for the knee)

• Possible surgery to release tight structures• Improve postural and biomechanical factors


• Injury to the Infrapatellar Fat Pad– Etiology

• May become wedged between the tibia and patella

• Irritated by chronic kneeling, pressure or trauma

– Signs and Symptoms• Capillary hemorrhaging and swelling• Chronic irritation may lead to scarring

and calcification• Pain below the patellar ligament

(especially during knee extension)• May display weakness, mild swelling and

stiffness during movement


• Injury to the Infrapatellar Fat Pad (continued)

– Management• Rest from irritating activities until

inflammation has subsided• Utilize therapeutic modalities for

inflammation• Heel lift to prevent irritation during extension• Hyperextension taping to prevent full

extension


• Chondromalacia patella– Etiology

• Softening and deterioration of the articular cartilage

• Undergoes three stages– 1. Swelling and softening of cartilage– 2. Fissure of softened cartilage– 3. Deformation of cartilage surface

• Often associated with abnormal tracking• Abnormal patellar tracking may be due

to genu valgum, external tibial torsion, foot pronation, femoral anteversion, patella alta, shallow femoral groove, increased Q angle, laxity of quad tendon


Figure 20-51


Chondromalacia

– Signs and Symptoms• Pain w/ walking, running, stairs and

squatting• Possible recurrent swelling, grating

sensation w/ flexion and extension• Pain at inferior border during palpation

– Management• Conservative measures

– RICE, NSAID’s, isometrics, orthotics to correct dysfunction

• Surgical possibilities– Altering muscle attachments– Shaping and smoothing of surfaces– Drilling– Elevating tibial tubercle


Patellofemoral Stress Syndrome

• Page 592


• Patellofemoral Stress Syndrome– Etiology

• Result of lateral deviation of patella while tracking in femoral groove

– Tight structures, pronation, increased Q angle, insufficient medial musculature

– Signs and Symptoms• Tenderness of lateral facet of patella and swelling

associated w/ irritation of synovium• Dull ache in center of knee• Patellar compression will elicit pain and crepitus• Apprehension when patella is forced laterally

– Management• Correct imbalances (strength and flexibility)• McConnell taping• Lateral retinacular release if conservative

measures fail© 2011 McGraw-Hill Higher Education. All rights

reserved.

• Osgood-Schlatter Disease and Larsen-Johansson Disease– Etiology

• Osgood Schlatter’s is an apophysitis occurring at the tibial tubercle

– Begins cartilaginous and develops a bony callus, enlarging the tubercle

– Resolves w/ aging– Common cause = repeated avulsion of patellar

tendon

• Larsen Johansson is the result of excessive pulling on the inferior pole of the patella

– Signs and Symptoms• Both elicit swelling, hemorrhaging and

gradual degeneration of the apophysis due to impaired circulation



Figure 20-53

– Signs and Symptoms (continued)• Pain w/ kneeling, jumping and running• Point tenderness

– Management• Conservative

– Reduce stressful activity until union occurs (6-12 months)

– Possible casting, ice before and after activity– Isometrics for quadriceps and hamstrings


• Patellar Tendinitis (Jumper’s or Kicker’s Knee)– Etiology

• Jumping or kicking - placing tremendous stress and strain on patellar or quadriceps tendon

• Sudden or repetitive extension

– Signs and Symptoms• Pain and tenderness at inferior pole of patella

– 3 phases - 1)pain after activity, 2)pain during and after, 3)pain during and after (possibly prolonged) and may become constant

– Management• Ice, phonophoresis, iontophoresis, ultrasound, heat• Exercise• Patellar tendon bracing• Transverse friction massage


Figure 20-54


• Patellar Tendon Rupture– Etiology

• Sudden, powerful quad contraction• Generally does not occur unless a chronic

inflammatory condition persists resulting in tissue degeneration

• Occur primarily at point of attachment

– Signs and Symptoms• Palpable defect, lack of knee extension• Considerable swelling and pain (initially)

– Management• Surgical repair is needed• Proper conservative care of jumper’s knee can

minimize chances of occurring• If steroids are being used, intense knee

exercise should be avoided due to weakening of collagen


Iliotibial Band Friction Syndrome (Runner’s Knee

or Cyclist’s Knee)• Page 595


• Iliotibial Band Friction Syndrome (Runner’s Knee or Cyclist’s Knee)– Etiology

• General expression for repetitive/overuse conditions attributed to mal-alignment and structural asymmetries

– Signs and Symptoms• IT Band Friction Syndrome

– Irritation at band’s insertion - commonly seen in individual that have genu varum or pronated feet

– Positive Ober’s test

• Pes Anserine Tendinitis or Bursitis– Result of excessive genu valgum and weak vastus

medialis– Often occurs due to running w/ one leg higher

than the other (running on a slope or crowned road)


– Management• Correction of mal-

alignments• Ice before and

after activity• Utilize proper

warm-up and stretching techniques

• Avoidance of aggravating activities

• NSAID’s and orthotics


Figure 20-5

Knee Joint Rehabilitation• General Body Conditioning

– Must be maintained with non-weight bearing activities

• Weight Bearing– Initial crutch use, non-weight bearing– Gradual progression to weight bearing

while wearing rehabilitative brace

• Knee Joint Mobilization– Used to reduce arthrofibrosis– Patellar mobilization is key following

surgery– CPM units


• Flexibility– Must be regained, maintained and improved

• Muscular Strength– Progression of isometrics, isotonic training,

isokinetics and plyometrics– Incorporate eccentric muscle action– Open versus closed kinetic chain exercises

• Neuromuscular Control– Loss of control is generally the result of pain

and swelling– Through exercise and balance equipment

proprioception can be enhanced and regained

– The patient must be challenged© 2011 McGraw-Hill Higher Education. All rights

reserved.


Figure 20-59

• Bracing– Variety of braces for a variety of

injuries and conditions– Typically worn for 3-6 weeks after

surgery• Used to limit ranges for a period of time

– Some are used to control for specific injuries while others are designed for specific forces, stability, and providing resistance

• Functional Progression– Gradual return to sports specific skills– Progress w/ weight bearing, move into

walking and running, and then onto sprinting and change of direction


• Return to Activity– Based on healing process - sufficient

time for healing must be allowed– Objective criteria should include

strength and ROM measures as well as functional performance tests


© 2011 McGraw-Hill Higher Education. All rights reserved. Chapter 20: The Knee and Related Structures.

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