PTA 130
Fundamentals of Treatment
The Knee
Lesson Objectives
Identify key anatomical muscles and structures
of the knee
 Identify common tissue injuries, conditions and
surgical interventions
 Analyze restorative interventions for common
injuries, conditions, and surgical procedures
 Identify soft tissue specific mobilizations
 Identify flexibility, strengthening, functional, and
stabilization exercises

Knee Structure

Joints:
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Capsule
Ligaments:
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Tibiofemoral
Patellofemoral (PF)
Medial collateral (MCL)
Lateral collateral (LCL)
Anterior cruciate (ACL)
Posterior cruciate (PCL)
Muscles:

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Quadriceps
Hamstring group
Gastrocnemius
Popliteus
Knee Structure
Primary stability comes from the ligaments
 Secondary stability from the joint capsule &
surrounding muscles
 The knee joint capsule encloses the
tibiofemorial joint and the patellofemoral joint
 A biaxial, modified hinge joint

Arthrokinematics
Depends upon open-chain or closed-chain
activities
 Tibial Motion- Open-chain

Flexion – Posterior slide
 Extension – Anterior slide

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Femoral Motion – Closed-chain
Flexion – Anterior slide
 Extension – Posterior slide

“Screw -Home” Mechanism
The rotation that occurs between the femoral
condyles and the tibia during the final degrees
of extension
 The femur rotates internally during closedchain activities (the tibia is fixed)
 As the knee is unlocked, the femur externally
rotates
 Acts as a stabilizing function of the knee joint

Referred Pain and Nerve Injuries
Sciatic nerve divides into the tibial and
common peroneal nerves just proximal to the
popliteal fossa
 L3 nerve root refers to the anterior aspect of
the knee
 S1 and S2 refer to the posterior aspect of the
knee
 The hip joint may refer symptoms to the
anterior thigh and knee

Nerve Injuries Around the Knee

Common Peroneal Nerve (L2-4)



Becomes superficial where it winds around the fibula
just below the fibular head, a common site for injury
Symptoms of sensory loss and muscle weakness are
distal to that site
Saphenous Nerve (L2-4)


Innervates the skin along the medial side of the knee
and leg
May be injured with trauma or surgery in that region
Joint Hypomobility & Common
Impairments
Degenerative Joint Disease
 Rheumatoid Arthritis
 Postimmobilization Hypomobility
 Capsule, muscle and soft tissue restrictions
 Adhesions may restrict gliding of the patella
further limiting knee mobility
 Motion loss usually flexion > extension
 Pain during AROM and weight bearing, disturbed
balance, sit to stand, stair climbing, squatting

Joint Hypomobility Management

Protection Phase
Control pain
 ROM techniques
 Setting exercises
 Patient education- splinting, bracing, exercise to
maintain mobility
 AD to relieve pain and stress on the joint
 Minimize stair climbing, elevated toilet seats, avoid
deep chairs or sofas

Joint Hypomobility Management

Controlled Motion & Return to Function Phase
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Continue patient education
Gentle joint mobilization
Patellar glides
Stretching techniques
Progressive strengthening
Muscular endurance
Functional training
Improve cardiopulmonary endurance
Joint Surgery and Postoperative
Management
Repair of Articular Cartilage
 Synovectomy
 Total Knee Arthroplasty
 Lateral Retinacular Release
 Anterior Cruciate Ligament Reconstruction
 Posterior Cruciate Ligament Reconstruction
 Meniscus Repair
 Partial Menisectomy

Repair of Articular Cartilage Defects
Injuries of the ligaments or menisci of the knee
and acute or chronic patellofemoral dysfunction
often are associated with damage to an articular
surface of the knee
 Surgical interventions are challenging because of
the limited capacity of articular cartilage to heal
 Indication for surgery is a symptomatic knee,
typically over weight-bearing portions of the
medial or lateral femoral condyles, the trochlear
groove, and the articulating facets of the patella

Repair of Articular Cartilage Defects
Microfracture
 Osteochondral Autograft Transplantation
 Osteochondral Allograft Transplantation
 Autologous Chondrocyte Implantation

Microfracture
Indicated for repair of small defects
 Performed arthroscopically
 Surgeon uses an awl (spike) to penetrate the
subchondral bone and expose the bone
marrow
 Stimulates a marrow-based repair response
leading to local ingrowth of cartilagenous
repair tissue to repair the lesion

Osteochondral Autograft
Transplantation
Indicated for focal lesions involving chondral
or subchondral tissue of the weight-bearing
surfaces of the knee
 Arthroscopic procedure involving the
transplantation of small areas of intact
articular cartilage into the site of the chondral
defect
 Bone-to-bone graft

Osteochondral Allograft
Transplantation
Typically used for defects larger than 4 cm
 Intact articular cartilage is taken from a
cadaveric donor
 Only fresh, intact grafts can be used for this
procedure

Autologuous Chondrocyte
Implantation
Used for full-thickness chondral and
osteochondral defects of the femoral condyles or
patella and occurs over two stages
 Stage One:



Healthy articular cartilage is harvested from the
patient, chondrocytes are extracted, cultured for
several weeks, and processed in a laboratory
Stage Two:


Implantation phase
Chondral defects are debrided, covered with a
periosteal patch, chondrocytes are injected under the
patch
Common Cause of Articular Cartilage
Defects

Chondromalacia
Softening of the articular cartilage of the patella
 Occurs most often in young adults
 Can be caused by injury, overuse, misalignment of
the patella, or muscle weakness
 Instead of gliding smoothly across the lower end
of the thigh bone, the kneecap rubs against it,
thereby roughening the cartilage underneath the
kneecap.

Common Cause of Articular Cartilage
Defects

Chondromalacia



The damage may range from a slightly abnormal
surface of the cartilage to a surface that has been
worn away to the bone
Trauma -a blow to the kneecap tears off either a small
piece of cartilage or a large fragment containing a
piece of bone (osteochondral fracture)
Treatment: low-impact exercises that strengthen
muscles without injuring joints, swimming (aquatic
therapy), taping techniques, bio-feedback
Synovectomy
Synovectomy is an operation performed to
remove partial or all the synovial membrane of
a joint
 May be an arthroscopic procedure or an open
procedure
 Indications for synovectomy of the knee:

Chronic, proliferative synovitis, joint pain,
restricted joint mobility
 Synovial hypertrophy and joint pain

Synovectomy

Postoperative Management – Maximum
Protection Phase
Knee is immobilized for 24-48 hours
 Ambulation with crutches
 Pain and edema control
 Regaining full, active knee extension is essential
 Knee ROM activities (patient will typically regain
full ROM within 10-14 days)

Synovectomy

Postoperative Management – Moderate, Minimum
Protection and Return to Function
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Activities to regain functional control of the operated
knee
Full weight-bearing
Cardiopulmonary fitness
Balance activities
CKC strengthening
Gait training
Proprioceptive training
Total Knee Replacement/Arthroplasty
(TKA)

Typically performed for advanced arthritis of the knee
Partial
Total
Knee Arthroplasty

Initial goal is to gain ROM

Hospital discharge criteria is usually 90 degrees of
knee flexion
Initiate activation of the quadriceps early
 QUADS, QUADS, QUADS! –


Knee extension needs to be complete –
goniometric measurement 0 degrees
TKA – Postoperative Management

Immobilization and Early Motion
Possible use of a CPM in the hospital
 Muscle setting exercises
 MD will determine weight bearing status for each
patient depending upon the type of implant used
 Ambulation with assistive device
 Pain and edema control
 Gentle patellar mobilization

TKA – Postoperative Management

Maximum Protection Phase
Progression to FWB
 Continued ROM and stretching activities
 Strengthening exercises – knee and hip
 Patellar mobilization
 Gait training
 Proprioceptive training

TKA – Postoperative Management

Minimum Protection and Return to Function
Phases
8-12 weeks and beyond
 Emphasize task-specific strengthening exercises
 Proprioceptive training
 Cardiopulmonary conditioning
 Recommendations for Participation in Physical
Activities Following TKA (pg. 709, Box 21.5)

Continuous Passive Motion (CPM)
Early motion encouraged
 Following surgery a continuous passive motion
(CPM) machine may be administered for the
patient at home
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Post-operative Exercise

Quad Sets

Ankle Pumps
Post-operative Exercise
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Heel Slides
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Straight Leg Raise
Lateral Retinacular Release
Designed to reduce an identified lateral tilt of
the patella and/or alleviate excessive
compressive forces on the lateral facet of the
patella
 Indications for surgery –
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
Chronic patellofemoral pain & functional
limitations without improvement after 6 months
of conservative treatment (taping, exercise,
bracing, meds, modification of daily activities)
Lateral Retinacular Release

Maximum Protection Phase (1-2 wks) –
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Moderate Protection Phase (3-4 wks) –
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ROM, control edema, strengthening, ADLs, HEP
Minimum Protection Phase (5-6 wks) –
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Control swelling & pain, ROM, patellar mobility, muscle
control, ambulation w/o AD, HEP
70% strength, patient education & monitoring for slow
return to activity
Return to Function Phase (>6 wks) –

Develop maintenance program & monitor for patient
compliance
Ligament Injuries
Ligaments provide the key stabilizing forces for
accessory motions (anterior/posterior
translation, medial/lateral pivots) of the knee
 Acute traumatic disruption or chronic laxity of
the ligaments results in excessive accessory
motions of the joint
 The ACL is the most frequently injured and
surgically repaired

Ligament Injuries
Anterior Cruciate Ligament (ACL) is most
often injured by a lateral blow to the knee or
twisting the knee on a planted foot
 Posterior Cruciate Ligament (PCL) is most
often injured by a direct impact, such as in a
dashboard injury (MVA) or falling on a flexed
knee
 “Terrible Triad”- ACL, MCL and medial
meniscus injured at the same time

Ligament Injuries

Medial Collateral Ligament (MCL) injuries
occur from a valgus force across the medial
joint line

Lateral Collateral Ligament (LCL) injuries
occur infrequently and usually from a
traumatic varus force
Common Impairments
Delayed swelling unless blood vessels are torn
 Complete tear - instability noted on special
tests
 With swelling, the knee assumes position of
minimal stress, flexed to 25 degrees and
inhibition of the quadriceps occurs
 Difficulty bearing weight for ambulation
 Knee may collapse during weight bearing
activities

Non-Operative Management
Rest, Joint Protection, Exercise
 Maximum Protection Phase
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PRICE
Use of an assistive device
Educate patient on safe transfers to avoid pivoting on
affected leg
Initiate Quad sets
Moderate Protection through Return to Activity

Improve muscle performance, function, CV condition
Ligament Surgery

Intra-articular vs. extra-articular

Intra-articular is used primarily for ACL and PCL
Open, arthroscopic, or endoscopic
 Indications:

Disabling instability
 Frequent knee buckling
 Positive pivot-shift test
 High risk of re-injury

ACL Post Operative Management

To brace or not to brace?

Depends upon the surgeon, approach, and graft
Generally weight bearing is allowed soon after
surgery
 Maximum Protection Phase- ACL


Delicate balance between adequate protection of
the graft and prevention of adhesions,
contractures, etc
ACL Post Operative Management
Achieve 90 deg flexion and full passive extension
by the end of the first week
 Moderate Protection Phase
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Achieve full ROM
Increase strength, endurance and balance
Ambulate w/o AD
Improve neuromuscular control, proprioception
Minimum protection to Return to activity phase
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Begins 10-12 weeks postoperatively
PCL Reconstruction
Injury of the PCL is relatively infrequent
 Usually accompanied by damage to other
structures of the knee
 Indications for surgery:

Complete tear or avulsion of the PCL
 Chronic PCL insufficiency
 Isolated, symptomatic, grade III PCL tear with
instability of the knee

PCL
Post Operative Management
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Generally braced in full extension
Weight bearing progressed gradually
Avoid exercises that create posterior shear of the tibia
on the femur
Maximum Protection Phase
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Control acute symptoms
Prevent DVT’s
Re-establish control of the quads
Maintain patellar mobility
Regain 90 deg flexion by 2 to 4 weeks
Begin to reestablish proprioception, neuromuscular
control and balance
PCL
Post Operative Management

Moderate to Minimum protection phase
Achieve full ROM by 9-12 weeks post-op
 Continue precautions to avoid excessive posterior
shear forces
 Advanced neuromuscular training with
plyometrics, balance and agility drills
 Progress aerobic conditioning
 Activity specific training
 Full return to sport may take up to 9 months

Meniscus

Outer - lateral meniscus
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Circular shaped , smaller ,more mobile
Attached to the ACL
Attached to the femur via the ligament of Wrisberg
Inner - medial meniscus
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“C” shaped
Wider posterior than lateral
Attached to the MCL
Attached to the joint capsule
Meniscal Injuries

A partial or total tear may occur when a person
quickly twists or rotates the upper leg while the
foot is planted


The medial meniscus is injured more frequently than
the lateral meniscus
Mechanism of injury to the medical meniscus usually
occurs with the foot fixed and femur rotates internally


Pivoting, getting out of a car, or a clipping injury
Mechanism of injury to the lateral meniscus usually
occurs with external rotation of the femur on a fixed
tibia
Meniscal Non-Operative Injuries
Meniscal tears may cause acute locking of the
knee or chronic intermittent locking
 Tears of the outer border with a rich vascular
supply heal well; central tears usually do not heal
and usually require surgery
 The age and activity of the patient determine if
surgery should be performed
 Exercises:
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Open and closed chain to improve strength and
endurance along with functional activities
Post-operative Meniscal Management
Primary surgical options are partial
menisectomy and meniscal repair
 Variables that determine exercise and weight
bearing progression

Location and nature of the tear
 Single tear vs complex
 Knee alignment


Bracing and weight bearing determined by
procedure
Post-operative Meniscal Management

Maximum Protection Phase
Begin post-op day 1
 Control pain, joint effusion and vascular
complications
 Regain functional ROM
 Prevent patellar restrictions
 Re-establish control of knee musculature
 Improve strength and flexibility of the hip and
ankle musculature
 Maintain cardiopulmonary fitness

Post-operative Meniscal Management

Moderate Protection Phase
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AD to provide some degree of protection with
ambulation
Restore full knee ROM
Improve LE flexibility, strength, muscular endurance
Neuromuscular control and balance
Minimum Protection Phase


Return to high level activity if adequate strength has
been restored
Full, non-painful ROM
Tendon Injuries

Tendinitis

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
Inflammation of a tendon
Overuse of a tendon (such as with dancing, cycling or
running) causes the tendon to stretch and become
inflamed.
Patellar tendinitis often results in:



Tenderness over the tendon
Inflammation
Ruptured tendon

A complete rupture of the quadriceps or patellar
tendon is not only painful, but also makes it difficult
for a person to perform functional activities
PATELLOFEMORAL
DYSFUNCTION
Patellar Orientation
Patellar Orientation
PF Compressive Forces
No compression in full knee extension
 Patellofemoral compressive forces increase
between 30°-90° of knee flexion
 Closed kinetic chain (CKC): 0° to 30°
produces minimal PF stress
 Open kinetic chain (OKC): <20° (without
weights) produces minimal PF stress

Patellar Malalignment

Patella Alta:


Patella is higher than its normal position in the
patellofemoral groove
Patella Baja:

Patella is lower than its normal position in the
patellofemoral groove
Q- Angle
The angle formed by the intersection of a line
drawn from the center of the patella to the
ASIS and a line drawn from the center of the
patella to the tibial tuberosity
 Subtract the above angle from 180 degrees
 Increased Q-angle may lead to increased
pressure of the lateral facet against the lateral
femoral condyle when the knee flexes during
weight bearing activities

Patellofemoral Dysfunction Treatment

Patient education– identify and correct causative factors




Minimize stair climbing
Avoid prolonged sitting with knee flexed
Evaluate patellar alignment & tracking in WB and NWB
Exercise & HEP Instruction


Increase flexibility of restricted tissue (ITB, Gastrocsoleus,
Hamstrings)
Correct muscle imbalances

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
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Latest research emphasizes lateral hip muscular strengthening to
improve alignment
Patellar mobilization
STM – cross friction massage
Taping - McConnell taping or K-taping
OTHER COMMON KNEE
DISORDERS
Osgood-Schlatter Disease
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A condition caused by repetitive stress or tension on part
of the growth area of the upper tibia
Inflammation of the patellar tendon and surrounding soft
tissues at the point where the tendon attaches to the tibia
Most commonly affects active boys, ages 10-15, who play
games or sports that include frequent running and jumping.
Presents as a bony bump that is particularly painful when
pressed - may appear on the upper edge of the tibia (below
the kneecap)
Typically, motion of the knee is not affected
Treatment:

ROM/Stretch, Stabilization/Isometric, modalities
Iliotibial Band Syndrome
An inflammatory condition caused when the IT
Band rubs over the outer bone (lateral condyle)
of the knee
 Although iliotibial band syndrome may be caused
by direct injury to the knee, it is most often
caused by the stress of long-term overuse, such
as sometimes occurs in sports training and,
particularly, in running and cycling


Treatment :

Stretching/ROM, modalities, STM
Osteochondritis Dissecans

Results from a loss of the blood supply to an area of bone
underneath a joint surface



The affected bone and its covering of cartilage gradually
loosen and cause pain
Usually arises spontaneously in an active adolescent or young
adult


i.e. retro surface of the patella
May eventually develop osteoarthritis
Treatment:

Stretching ROM and low-impact exercises that strengthen muscles
without injuring joints, swimming/aquatic therapy, modalities
COMMON EXERCISES FOR
THE KNEE
Prolonged Extension Stretch in
Long Sitting
Wall Slides
Anterior Thigh Stretch
Knee Strengthening Exercise
SAQ’s
 SLR’s
 Wall Sits/Squats
 Fitter
 “Monster Walks”
 Lunges
 Repeated Step Ups/Step Downs
 Balance activities

Orthopedic Special Tests
One Plane Medial Stability

Valgus Stress Test
The test is positive if the
tibia moves away from the
femur an excessive amount
 What structures are
affected:
 In full extension versus
 In 20-30 degrees of flexion

One Plane Lateral Stability

Varus Stress Test
The test is positive if the tibia moves away from
the femur an excessive amount
 What structures are affected:
 In full extension versus
 In 20-30 degrees of flexion

One Plane Anterior Instability

Lachman Test
Best indicator of injury to the ACL, especially the
posterolateral band
 A positive sign is indicated by a mushy end feel
when the tibia is moved forward on the femur

One Plane Anterior Instability

Drawer sign


A positive sign is
indicated when the tibia
moves more that 6mm
on the femur
What if the PCL is torn??
One Plane Posterior Stability

Drawer Test

The test is positive in the same manner as the
Anterior Test
One Plane Posterior Stability

Godfrey (Gravity) Sign

If there is a posterior instability, a posterior sag of
the tibia is seen
Tests for Meniscus Injury

McMurray Test

A positive result is when there is a snap or click
from a loose fragment and usually accompanied by
pain.
Tests for Meniscus Injury

Apley’s Test
If rotation plus distraction is more painful consider
ligament injury
 If rotation plus compression is more painful
consider meniscus injury

Tests for Meniscus Injury

Bounce Home Test
Not done very often in the
clinic
 A positive test is noted
when extension is not
completely achieved or is
springy block as well as
sharp joint pain when
quickly extended

QUESTIONS?