Chan Hon Yan
99060146D
Chan Man Leung Sunny 99946540D
Choi Chor Kei Leo
99199765D
Fung Mo Ching Ivy
99023277D
Topic 2
Mary, a 21 years old University student,
belongs to Hong Kong Basketball Team.
She twisted her (L) knee while landing from a
rebound during competition 3 months ago.
Her doctor informed her that she had suffered
from a grade II ACL injury, and recommended
Mary to have intensive rehabilitation with
special emphasis on functional training.
Outline of Presentation
Gender
Sports Skill
Pathology
Psychology
Rehabilitation
Program
Return to Sports
Introduction
In a 5 year study, knee injuries accounted for
15% of total basketball injuries in National
Collegiate Athletic Association (NCAA).
Almost 20% of the knee structure injuries are
ACL injury.
The ACL injury rate in women was 4.1 times
greater in basketball.
(Arendt & Dick, 1995)
Injury mechanism
Non-contact
 planting
& cutting
 straight-knee landing
 one-step landing with
the knee hyperextended
 pivoting & sudden deceleration
Effects on Structures after
ACL injury
Static stabilizer
Medial menisci --- increase cross sectional
area and volume, thickening at its
attachment
 Posterior capsule --- thickening (Jackson et
al., 1999)
 Decrease Bone Mineral Density (BMD) in
the periarticular cancellous bone of femur
and tibia (Boyd et al., 2000).

Effects on Structures after
ACL injury
Dynamic stabilizer
Hamstrings
 Quad
 Gastrocnemius

Increase demand
Non-copers vs Copers
Non-copers
 had instability with activities of daily living .
 They stiffened their knees by landing in
less flexion and accepting weight with less
flexion in both walking and jogging.
 May lead to excessive joint contact forces
which have potential to damage articular
structure. (Rudloph et al., 1998)
 cannot return to previous performance
Non-copers vs Copers
Copers
 return to all pre-injury activity without
limitation.
 Copers demonstrated increased
hamstrings EMG, may be a compensation
mechanism.
(Tibone & Antich, 1993 and Boerboom et al., 2001)

It has been suggested that Quadriceps and
Gastrocnemius are also important for
compensatory dynamic knee stabilization.
(Nyland et al., 1997 and Kivist & Gillquist, 2001)
Why are women more
susceptible?
Intrinsic factors (Huston LJ. et al, 2000)
Q-angle
 femoral notch
irreversible
 joint laxity
 hormonal influence - need more research
to prove

Why are women more
susceptible?
Extrinsic factors
Proprioception
 muscle strength
 neuromuscular control
 knee stiffness

Risk Factors
Proprioception (Rozzi SL. et al, 1999)
Female took longer than male to detect
joint motion moving in the direction of knee
joint extension
 May be less sensitive to potentially
damaging force
Increase risk for ligament injury

Risk Factors
Muscle strength (Huston LJ. & Wojtys EM.
1996)

Female athletes has weaker knee extension
& flexion strength than male
Risk Factors
Neuromuscular control

Muscle recruitment pattern response to
anterior tibial translation (Huston LJ. & Wojtys
EM. 1996)

Female athlete – quad-dominant
Male athlete, men and female control subjects –
hamstrings-dominant

quad-dominate pattern: more strain on
the ACL than cocontraction or contract
the hamstrings first
Risk Factors
Knee stiffness
Important component to knee stability and
injury prevention
 Mm increase the joint contact force &
decrease tibiofemoral displacement,
dissipating potentially dangerous loads,
lowering the force carried by the ACL and
other passive structure

Risk Factors
Knee stiffness

Valgus & Varus stiffness (Brant JT. & Cooke TD.,1988)


knees in female rotate 66% more than males
& 35% less stiff
Ability to voluntarily stiffen the knee
(Wojtys EM et al, 1999)
Men: 4 times
 Women: 2 times

Basic Skill
in basketball
Running
Cutting
Pivoting
Rebounding
Shooting
(adapted from R J Emerson 1993)
Running
Change of speed and direction
To get away from opponents
 To guard the route of offending opponent

require slide-steps, backward steps
Sudden deceleration & stopping prior to
change of direction
 knee almost fully extended +
twisted
Cutting
Use of technique such as fake, stops
and pivot to get away from opponent
Cutting method
Side-step Cut
 Cross-over Cut

Require sudden change of
Speed
 Direction

Pivoting
Use of technique getting away from
opponent by moving body and step one
or more steps on one foot while keeping
the other stationary
 Produce tibia torsion to knee
Points to consider in return
to sport
Position
Habits in
performing skills
Position
Center



Perform much pivoting under net for scoring
Require more strength in jumping
Many collision and body contact under net
Need more proprioceptive training for
balance during landing
May consider any uses of brace to prevent
re-injury
Position
Wing & Guard
Perform many high speed cutting
and shooting with 2-steps stop
 Perform much dribbling
 Abilities required:

High power in initiating movement
 High agility with sudden change of cutting
direction or pace

need to  stabilization of knee & agility
Habit in Skills
Kirkendall DT et al (2000)
Cutting maneuver with less knee & hip
flexion with knee valgus
 Higher injury rate of ACL
training to perform cutting with knee 
flexion
 ACL injury reduced by 89%
Psychological Support
Explain to player
nature and severity of the injury
 prognosis for recovery
 recommended courses of therapy
 estimate time frame of rehabilitation

Reassurance and support
Peer support
Visual-Motor Behaviour Rehearsal
(VMBR)
Rehearse an entire performance

e.g. Landing with proper foot placement
Review and correct a specific
performance

e.g. Remind herself the wrong habit in sport
Practice approaching the crowd or
competition with confidence
Goals of rehabilitation
Gender aspect:

To minimize possible risk factors for recurrence of
ACL injury in female basketball player
Sports aspect:

To restore physical capacity in competing in
basketball games
Psychological aspect:

To overcome fear associated with the injury
movement
Functional Training
Perturbation training
Plyometric training
Agility training
Sport-specific training
Perturbation Training
Techniques involving perturbation of
support surfaces
roller board
 tilt board
 roller board & stationary platform

Induce compensatory muscle activity
Advantages of
Perturbation Training
Fitzgerald et al., 2000:
Enhance the probability of successful return
to high-level physical activity

perturbation group with greater long-term success
Improve knee stability

reduce the risk of continued episodes of giving
way of knee during athletic participation
Plyometric Training
Neuromuscular training
Develop power, strength & coordination
involve a prestretching of muscle 
induce the stretch-shortening cycles
Plyometric Training
Goal:
Decrease reaction time between eccentric
lengthening of mm and concentric mm
contraction
 Increase power

Advantages of
Plyometric training
Hewett et al, 1996 &1999:
Decrease landing forces
Increase vertical jump height
Improve knee stabilization

Improve hamstring-to-quadriceps strength ratio
 Decrease incidence of knee injury in female athletes
Examples of
Plyometric Training
Hewett et al, 1996 &1999:
Cone jump
Jump, jump, jump, vertical
Agility Training
Allow pt to adapt to:
quick changes in direction
 quick starting and stopping
 cutting & pivoting
 improve proprioception

Agility training significantly improves mm
reaction time in response to anterior tibial
translation (Wojtys et al, 1996)
Figure-of-eight Drills
gradual change of direction
allow adaptation to cutting activity
Longer distances  shorter distances
(smaller surface area  tighter “8” )
 backward “8”

Cutting Maneuver Drills
Sidestep cut
Crossover cut
half-speed  full-speed
 45o  60o  90o cutting
 Carioca

Shuttle Run
Involve straight plane running,
acceleration, deceleration, cutting &
pivoting
•SEMO drill
Others
•incorporate forward, backward, diagonal
acceleration and lateral movt
Start
Sport Specific Training
Start when full speed agility training was
achieved
sport specific tasks are added during the
agility training
For basketball player:



Dribbling skills
Ball catching
Ball passing
Sport Specific Training
Started w/o being opposed
Progressed to one-on-one opposition
Progressed to real competition
Question & Answer
Session
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