Download Chapter 14 Knee Injuries

Chapter 14
Knee Injuries
The Knee
• Largest joint in the
body
• Modified hinge joint
• One of most
vulnerable joints to
severe injury of any
in the body
Knee Anatomy
• Bones
– Tibia
• Distal to the femur
• Major weight bearing
bone
– Fibula
• Not included as a true
knee bone
• Very little weight bearing
– Femur
• Longest bone in the body
• Major weight bearing
– Patella
• “floating bone”
Knee Anatomy
• Ligaments
– Anterior cruciate
ligament (ACL)
• “cruciate” means cross
• Function of ACL and
PCL is to stabilize the
knee from front-toback
– Posterior cruciate
ligament (PCL)
– Medial collateral
ligament (MCL)
– Lateral collateral
ligament (LCL)
ligaments
– Posterior cruciate
ligament (PCL)
– Medial collateral
ligament (MCL)
– Lateral collateral
ligament (LCL)
Knee Anatomy
• Cartilage (meniscus)
– menisci are horseshoeshaped shock absorbers
that help to both center
the knee joint during
activity and to minimize
the amount of stress on
the articular cartilage.
Meniscus
– Medial
• More often injured than
lateral
• Often involved medial
ligament
• C-shaped
– Lateral
• O-shaped
Knee anatomy
• Patellar tendon
– Runs from the
quadricep muscles,
across the patella,
and inserts into the
tibial tuberosity
Knee Anatomy
• Muscles and tendons
– Quadricepsresponsible for knee
extension
•
•
•
•
Vastus lateralis
Vastus medialis
Vastus intermedius
Rectus femoris
Quadriceps
Posterior Leg
– Hamstringsresponsible for knee
flexion
• Biceps femoris
• Semimenbranosis
• semitendinosis
Hamstrings
Injury prevention
• Structural alignment
can predispose an
athlete to injury
Injury Prevention
• Proper
strengthening and
flexibility of
quadriceps,
hamstrings, and
gastrocnemius
muscles
Injury Prevention
• Preventative
bracing for
collateral
ligaments
Genu valgum (knock-kneed)
Genu Varum (bow-legged)
Bracing
Knee injuries and Conditions
• Ligament Injuries
– Sprains (ACL, PCL, MCL, LCL)
• 1st, 2nd, and 3rd degree
• Muscle and tendon injuries
– Patellar tendinitis
• Bone injuries
– Chondromalacia
– Patellar dislocations
• Other common injuries
– Meniscal injuries
– Osgood-Schlatter disorder
Ligament Injuries
ACL injuries
• Function is to
prevent tibia from
moving forward on
femur
• S/S of injury include
the athlete feeling
disabled, complain of
the knee giving way,
collapsing, and
popping
ACL Injuries
• Usually the most
serious of all knee
injuries
• Can hear a pop or
snap on injury
• Often injured when
athlete is changing
direction
ACL (cont.)
• Can also be injured due
to hyperextension
• rapid swelling and loss
of function
• treatment- RICE, knee
immobilizer, crutches,
follow-up with
orthopedist
• Almost always require
surgical reconstruction if
torn
Surgical procedures
• Tendon graft
– Patellar or
hamstring
• Allograft
– Cadaver tendon
Rehabilitation
• 3 Phases of rehab include:
– controlling the pain and swelling in the knee
– regaining knee motion
– beginning to regain muscle strength
• Usually minimum 6 months
• Conservative treatment for less active people
can be non-surgical and focus on all rehab
– three components of non-surgical treatment are
physical therapy, activity modification, and the use
of a brace
PCL injuries
• PCL prevents
posterior tibial
movement on the
femur
• MOI: bent knee
bears full weight,
forced hyperflexion,
or a blow to the front
of the tibia
PCL
• Often minimal
swelling
• Treatment- RICE,
refer to physician
• Not often surgically
repaired
• Rehab focuses on
strengthening quad
muscles
MCL injuries
• Usually results from
a direct blow to the
outside of the knee
• Mild sprains result in
joint-line point
tenderness, minimal
swelling, and no joint
laxity
MCL
• Moderate
produces more
swelling,
discomfort, some
loss of function,
and some laxity
• Severe –
produces large
amount of laxity
MCL (cont.)
• Treat with RICE if mild
• Moderate, may need immobilizer, rehab
• Moderate to severe could involve the meniscus
and/or ACL and may require surgery
LCL injuries
• Less common than
MCL injuries
• Usually occurs due
to direct blow to
medial side of knee
LCL
• Similar s/s except
discomfort is on
lateral aspect of
knee
• Focus rehab on
lateral thigh
muscles and
hamstrings
Muscle and tendon injuries
• Patellar tendinitis
– Characterized by
quad weakness
and tenderness
over patella
– Minimal swelling
– Called jumper’s
knee
Patellar Tendinitis
– Pain after activity
– Treat with ice,
NSAIDs, and
restricting activity
– Rehab- address
flexibility and
weakness issues
Bone injuries
• Patellar-femoral
syndrome
– Pain and discomfort
around the patella
often caused by
patellar tracking
problems
– Causes
chondromalacia-the
wearing away of the
cartilage on the back
of the patella
Patellar-femoral syndrome
• s/s aching and pain after
prolonged sitting, pain
when going up or down
stairs, athlete feels
grinding sensation with
flexion/extension
Patellar-femoral syndrome
• Treatment involves
correcting patellar
tracking, strengthening
vastus lateralis and
medialis, improving
flexibility of quads and
hamstrings
Bone injuries
• Patellar dislocation
– Most commonly
dislocates laterally
– Occurs with bent
knee and inward
twisting
– Noticeable deformity,
extreme pain
– Call EMS
– Physician reduces
Patellar dislocation
– Treatment involves
immobilization, then
rehab to regain
mobility and
strengthen
– Can wear a knee
sleeve post-injury to
help prevent from
happening again
Fractures
• Tib-fib fracture
– Uncommon, but
immediate referral
necessary
– Many structures
involved
Dislocated knee
• Extremely rare
• Immediate
transport
Meniscal injuries
Typically occur with
a twisting motion
or with
hyperextension or
hyperflexion
• s/s-pain over joint line,
problems weightbearing,
complain of clicking,
catching, locking,
inability to fully extend or
flex, and swelling
Meniscal injuries
• Treatment- surgical removal of meniscus
(meniscectomy)
– More often treated with removal of torn areas only through
arthroscopy
– Sometimes repair meniscus with sutures or staples
– Numerous new methods of repair (i.e. transplants)
– Aquatic therapy very useful (non-weight bearing)
Osgood-Schlatter disorder
• Inflammation and
irritation of the insertion
of the patellar tendon
(tibial tuberosity) in youth
• Repeated stress and
activity can cause patella
to partially pull away
from bone and cause a
bump
Osgood-schlatter’s
• S/S- pain and
discomfort, minimal
swelling
• Restricted activity
recommended
• Use pain as a guide
for activity level
• Ice pre and post
activity, NSAIDs
Osgood-schlatter’s
• Can try patellar
tendon band or pad
• Usually improves by
age 16 or 17
Osgood-Schlatter disorder
Special tests
Lachman’s test
Pivot shift test
McMurray’s test