After undergoing knee microfracture surgery in October 2005

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After undergoing knee microfracture surgery
in October 2005, followed by a progressive,
corrective rehab program, Amare Stoudemire
has regained his all-star form.
treating the athlete
Micro Holes,
Macro Results
In the past, suffering a chondral defect often meant an end to an
athlete’s career. Today, exciting advances in microfracture surgery and
rehab are allowing players to come back more explosive than ever.
BY R.J. ANDERSON
W
hen Phoenix Suns
center Amare Stoudemire awoke from
anesthesia on Oct.
11, 2005, he heard
the word every basketball player
dreads: microfracture. Complaining
of intermittent knee pain that had
been lingering for weeks, Stoudemire
had elected to have a diagnostic
arthroscopy. He knew ahead of time
that the surgeon might find a significant cartilage defect and immediately
perform a microfracture procedure.
But he was hoping that wouldn’t be
the case.
Fear of microfracture surgery is very
real. Stoudemire undoubtedly recalled
the returns of high-profile NBA players Chris Webber, Allan Houston, and
Anfernee Hardaway—none of whom
recaptured their pre-injury greatness
after having the surgery.
But thanks to the skills of a premier
orthopedic surgeon utilizing the latest
microfracture technique, and a carefully designed, full-body rehab program steeped in corrective exercise,
Stoudemire did regain his form, earning first-team All-NBA honors at the
end of the 2007 season. He also gave
athletes with cartilage damage new
hope, including 2007 NBA numberTRAINING-CONDITIONING.COM
one draft pick Greg Oden, who underwent the procedure in August.
ON THE TABLE
Microfracture surgery is performed
to restore damaged articular cartilage, sometimes called a chondral defect. Such defects can occur any place
cartilage exists, and in the knee they
are most commonly found at the tibial
condyles, the femoral condyles, or the
backside of the patella where it contacts the tibia and femur in the medial
compartment. How these injuries develop is not always clear, but they seem
to occur either through a twist of a
bent knee, a direct blow, or after a series of minor injuries.
The goal of the surgery is to bring
blood and bone marrow to the defective
area through a blood clot that contains
tissue-building stem cells. The term
“microfracture” refers to the tiny holes
a surgeon makes in the patient’s bone
that allow the blood and stem cell-containing bone marrow to seep into the
area. With proper rehab, the tissue is
trained to become healthy cartilage as
it heals over the defective area.
While this surgery has been around
for nearly 20 years, both the procedure and the rehab approach have
greatly improved over the last decade.
Before microfracture surgery was considered a viable option for elite injured
athletes, those with chondral defects
simply lived with the pain, usually experiencing a decline in performance
and a shortened playing career.
A key part of any microfracture surgery is debriding the calcified “old”
cartilage and creating a bed in which
the new cartilage can form. Richard Steadman, MD, Orthopedic Surgeon and co-founder of the Steadman
Hawkins Clinic in Vail, Colo., who is
credited with pioneering knee microfracture surgery in the late 1980s and
remains one its most successful practitioners, says completely removing the
deepest layer of calcified cartilage is a
surgical advance developed in the last
five years or so.
“If the area where you’re trying to
build new cartilage still has a layer of
the old cartilage, it resists allowing the
new cartilage to form,” says Steadman.
“If you don’t remove that layer and create a bed on the bone with edges of
stable cartilage surrounding it, we’ve
found the chances of success are quite
a bit lower. The healthy rim of cartilage
R.J. Anderson is an Assistant Editor
at Training & Conditioning. He can be
reached at: [email protected].
T&C april 2008
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treating the athlete
around the bed decreases the amount of
pressure shouldered by the new tissue
and provides a cushion during the healing process.”
After a bed to house the new cartilage
is created, a curved surgical awl is used
to make microscopic punctures spaced
about three or four millimeters apart
at the ends of the bone. Steadman says
surgical advances were prompted by his
equine work, including the timeframe
of his rehab protocol—especially the
protective weight bearing phase. Most
protocols call for the athlete to spend
the first six to eight weeks post surgery
in a protective weight bearing environment, and Steadman recommends a full
eight weeks.
Over time, Steadman says the procedure has evolved to
incorporate shallower holes … “We’ve learned that
you don’t have to go very deep, just enough to access
the bone marrow. If you go farther than that, the
surgery is less likely to be successful.”
using the awl allows surgeons to penetrate the subchondral bone while leaving the subchondral plate intact. “The
subchondral plate is important for the
functioning of articular cartilage, so
most cartilage experts feel it is better to
leave that plate in place,” he says.
Over time, Steadman says the procedure has evolved to now incorporate
shallower holes—about three millimeters deep. “We’ve learned that you don’t
have to go very deep, just enough to access the bone marrow,” he says. “If you
go farther than that, the surgery is less
likely to be successful.”
After the blood and marrow accumulate in the freshly scraped bed on the
bone, the stem cells begin their healing magic, forming a new layer of tissue. This tissue consists mostly of type
II collagen, which is the major protein
found in cartilage and serves as the
“glue” that holds the cartilage together while helping to provide elasticity
within the joints. Type II collagen also
contains mucopolysaccharides, which
help the cartilage to heal itself.
“Articular cartilage is type II collagen,” Steadman says. “In a study we
did on horses, we were able to take
samples of regenerated cartilage and
analyze them in several cases, and it
turns out 70 percent of the new cartilage is made up of type II collagen—
meaning it’s very similar to the original
tissue.”
The molecular makeup of the regenerated cartilage isn’t the only discovery Steadman credits to the horse study,
which he conducted in collaboration
with the Colorado State University College of Veterinary Medicine and Biomedical Sciences. He says a number of
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“We looked at horses’ cartilage after two weeks, four weeks, six weeks,
and eight weeks, and found that eight
weeks is when it looked mature enough
to take the pressure of full weight bearing,” he says.
Another key part of the rehab protocol is to begin continuous motion immediately. “Basically, our theory is that
the new tissue needs a mechanical message to tell it what it should become,”
explains Steadman. “With cartilage,
you’d like a message that tells the new
tissue it needs to be smooth and to fill
in the defect. You want motion to convince these cells that they want to be-
stimulate the tissue to form a better
quality cartilage.”
Ready for rehab
In Stoudemire’s case, the arthroscopy
revealed a fairly small lesion—a onecentimeter by one-centimeter chondral defect. Still, Thomas Carter, MD,
an orthopedic surgeon at The Orthopedic Clinic Association in Phoenix
and Team Physician for the Suns, decided to go ahead with the microfracture surgery, fearing that if left alone,
the damaged cartilage would flake off
and expand the lesion. During the 30minute procedure, Carter scraped the
damaged tissue in the femoral condyle
region of Stoudemire’s knee, then made
five microfracture holes to trigger the
formation of the replacement cartilage.
The surgery deemed a success, Stoudemire readied himself for the long, arduous journey back. For the first week,
he was at home with his knee completely unweighted, undergoing ice compression treatments and hooked up to a
CPM machine.
Meanwhile, Suns Head Athletic
Trainer Aaron Nelson, ATC, NASMPES, CSCS, was hard at work, drawing
up a blueprint for Stoudemire’s rehab.
While he had assisted with other microfracture rehabs, this would be Nelson’s
first experience with an athlete fresh off
of the surgery.
“We’re not positive what caused the cartilage damage,
but our plan was to identify and eliminate any type
of dysfunction that could cause a problem down the
road or that might have contributed to his pre-surgery
problems. At the same time we were rehabbing the
knee, we wanted to address those other issues.”
come cartilage, not bone or muscle or
anything else. The constant motion
and protective weight bearing are factors that send the right message to those
cells.”
To provide the motion, immediately
after surgery, patients can use a continuous passive motion (CPM) machine.
“After about two to four weeks, if the
patient is doing well, I’ll allow them to
spin on a stationary bike, which gives
them that smooth exercise,” Steadman
says. “Then they can begin deep water running in which they don’t touch
the bottom. Those types of movements
“I started my research by finding out
everything I could on other athlete rehabs, and I looked at different surgeons’ protocols,” Nelson says. “Then,
Dr. Carter and I had a long conversation about his expectations and what
he thought would and should happen
throughout the process.”
Nelson also consulted with Micheal
Clark, DPT, MS, NASM-PES, President
and Physical Therapist at the National
Academy of Sports Medicine, to design
a comprehensive science-based rehab
program. “We took what everybody
else had done in the past and looked at
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treating the athlete
SMOOTH MOVES
When Micheal Clark, DPT, MS, NASMPES, President and Physical Therapist at
the National Academy of Sports Medicine,
evaluates athletes who are at risk for articular
cartilage damage in the knee, these are the most
common compensation patterns he sees, which
tend to occur when an athlete cuts, lands, or
decelerates from a jump:
Tibial external rotation: The athlete’s foot
turns to the outside during landing and then
caves inward. “That causes a shear force of
the femur moving across the tibia and creates
repetitive microtrauma of the articular cartilage,” says Clark.
Trunk flexing forward: When an athlete lands
from a jump, instead of keeping their trunk
upright and parallel to their lower leg, their chest
collapses toward their knees. “When the athlete’s trunk flexes forward, they lengthen the
gluteus maximus, which forces the hamstring to
eccentrically control the lower leg and the loading of hip flexion,” says Clark. “And if their foot is
already turned out into external rotation, they’re
facilitating the lateral hamstring, or biceps femoris, which causes stress at the knee.”
Limited dorsiflexion in an opposite ankle:
“Let’s say it’s the right knee that’s bothering an
athlete,” Clark says. “In many cases, we see that
the left ankle is restricted. If an athlete jumps
for a rebound and lands, the dorsiflexion when
landing from a jump needs to be at about 15
degrees. But many NBA players we see only
have five degrees of dorsiflexion.
“If their ankles don’t bend, their knees must deal
with the force,” he continues. “And the next joints
up from the knees are the hips, then the spine.
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When they land, they have to shift the weight
over to their right and their right knee takes most
of the eccentric load, and you get shear, compressive force on the joint that creates trauma.”
Limited motion in the big toe: Clark says his
assessments show that a lot of athletes have
restrictions in one or both big toes. “If you’re
loading eccentrically to jump, you have to get
motion at your big toe,” he says. “If a restriction
exists and the big toe can’t bend backward, the
foot has to flatten out to compensate. When that
happens, it lengthens the muscles on the inside
of the calf, and then the muscles on the outside
of the calf have to work too hard.
“If there is an imbalance where one side is pulling harder than the other, the joint will move in
the direction of the muscle that’s pulling harder,”
Clark adds. “That turns the foot to the inside,
and if you jump, land, cut, or do anything with
your knees in that position, the femur has to slide
across, which creates massive stress.”
When rehabbing athletes from a microfracture
procedure, Clark recommends athletic trainers
and physical therapists go through a proper joint
assessment, starting with the big toe and working their way through the ankle and hips, and
also testing hamstring length, hip internal rotation, and hip extension. “Those are the primary
areas that have to be within a certain range of
motion,” Clark says. “If you don’t restore those
joint motions when the athlete is rehabbing from
microfracture, and they begin bearing weight,
they will put increased stress on the microfracture in an early stage, which then creates
swelling in the joint and doesn’t allow the cartilage to heal very well. That’s a big problem we’ve
seen in a lot of the failed micros of the past.”
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treating the athlete
what would be best for Amare, then basically laid out a plan and moved forward,” Nelson says.
Determining what would be “best for
Amare” began before the surgery, when
Nelson evaluated Stoudemire from
head to toe. “We did a Kinetic Chain
Assessment (KCA) of his overall body
strength, flexibility, and mechanics prior to the surgery,” says Nelson. “We’re
not positive what caused the cartilage
damage, but our plan was to identify
and eliminate any type of dysfunction
that could cause a problem down the
road or that might have contributed to
his pre-surgery problems. At the same
time we were rehabbing the knee after
microfracture surgery, we wanted to
address those other issues.”
There are a few schools of thought
on what triggers a chondral defect, and
it’s fairly certain there is no single answer. For example, some experts feel
that a bone bruise can cause swelling
and lead to microtrauma that worsens
over time. There also seem to be some
acute cases when an impact instantly
tears the cartilage.
Regardless, Clark, who provides con-
tinuing education programs to the NBA
Athletic Training Association, says his
10-plus years working with athletes
who have had microfracture surgery
lead him to believe there are usually
movement impairments that contribute
to the injury. (See “Smooth Moves” on
page 18.) He says identifying and correcting those deficiencies is important
When planning the rehab, a major
goal was to have Stoudemire’s deficiencies corrected during the protective
weight bearing phase. “That was a perfect time for us to hammer out those
deficiencies and create activation of
those muscles and joints that had been
shut off,” Clark explains. “That way,
when he started to fully bear weight
When planning the rehab, a major goal was to have
Stoudemire’s deficiencies corrected during the protective
weight bearing phase. “That was a perfect time for
us to hammer out those deficiencies and create activation
of those muscles and joints that had been shut off.”
to both preventing future injury and
compensating for complications during
and after rehab.
“We try to identify these movement
impairments and typically find they are
a result of certain muscles that are too
short and too tight,” says Clark. “This
leads to movement impairment and
muscle imbalances that can create trauma at the knee.”
again, he would have symmetrical joint
motion and symmetrical muscle activation, which would take as much stress
as possible off his knee during rehab.”
MAKING CORRECTIONS
For the pre-surgery KCA, Stoudemire
performed several exercises and movements. Most telling were his compensations during an overhead squat. “If the
Circle No.
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Circle No. 110
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treating the athlete
athlete has proper range of motion in
the ankles, knees, and hips, and proper
muscle activation in the lower leg, hip,
stomach, and low back, they’ll be able
to squat down while keeping their feet
straight with their knees lined up over
had Stoudemire doing single-leg lower-body work with his non-injured leg
and workouts on a stationary bike. Increasing the weight he was able to bear
was largely facilitated through hydrotherapy. Once his incisions had healed
Many variables determine whether or not an athlete
successfully returns from microfracture surgery,
but Nelson focuses on three controllable factors.
“One, you’ve got to have an experienced surgeon
who does a great job. Two, you need the athlete to be
motivated and compliant. And three, the athlete
has to do everything the rehab team asks.”
their second and third toe and their
trunk upright,” Clark says.
“But what we see with a lot of athletes is that when they squat down, they
either pronate, their feet turn out and
their knees cave in, or their spine moves
into flexion,” he continues. “Those are
movement impairments and potential
predictive factors of overuse injury at
the knee. They can lead to serious articular cartilage damage, which could then
necessitate microfracture surgery.”
One particular impairment Nelson
and Clark discovered in Stoudemire was
weakness in his upper gluteus maximus—a deficiency that has far-reaching
implications. “When you’re running,
at the point when one foot is forward
and one foot is back, your opposite arm
and lat work together to create that
motion,” explains Clark. “If you have
weakness in one of your glutes, the opposite lat has to work too hard and that
can make it short and tight. If your
left glute is weak, your right lat can be
tight, and a tight right lat can rotate the
right side of your pelvis forward, creating a pelvic imbalance that can cause a
variety of complications, including additional stress on the knee.”
During the eight weeks of protective
weight bearing work, Stoudemire worked
with Nelson and Clark for three hours
a day, five days a week. He performed
foam rolling, stretching, and isolated,
non-weight bearing corrective exercise,
including plenty of work to strengthen
his intrinsic core muscles. Many of the
corrective exercises focused on strengthening his upper gluteus maximus.
After four weeks, the rehab team
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10 days post surgery, Nelson had Stoudemire in the water every day possible.
“As he progressed and regained most
of his range of motion, after about 10
to 12 weeks, we were able to do more
partial weightbearing stuff with him—
then he was only in the pool two to
three times a week,” says Nelson, adding that Stoudemire still does hydrotherapy as preventative maintenance.
From there, Nelson and Clark evaluated Stoudemire’s swelling, quadriceps
girth, and range of motion in the knee
before progressing. “Every day we
measured swelling of the knee joint—
which should decrease every day postsurgery. If it went up, we backed the
rehab off instantly,” Clark says. “We
also looked for increased range of motion every day. If for some reason he
lost motion, we backed off. His quad
girth also had to increase in order for
us to move forward.”
Although the rehab was long, Nelson
says everything went smoothly. “It’s
tenuous and redundant, which is challenging mentally—you do a lot of the
same stuff over the different phases,”
he says. “But it was my job to reassure
Amare and help him fight through the
boredom. You have to make the athlete realize that everything is a stepping
stone and you’re going one block at a
time as you build them up.”
A SUCCESS
Many variables determine whether or
not an athlete successfully returns from
microfracture surgery, including the
size and location of the lesion, and the
athlete’s medical history. But Nelson fo-
cuses on three controllable factors.
“One, you’ve got to have an experienced surgeon who does a great job,”
he says. “Two, you need the athlete to
be motivated and compliant. And three,
the athlete has to do everything the rehab
team asks.”
In Stoudemire’s case, all three were satisfied. He emerged from his rehab more
balanced, more flexible, and with greater
intrinsic core strength. A strong, healthy
knee and a return to explosiveness were
the end products of his hard work.
Though a success, Stoudemire’s rehab
was not without hiccups. He missed
nearly one full season of play, and
wasn’t back to full strength until midway through the 2006-07 campaign.
In the time since the microfracture
surgery, he has had two additional arthroscopies—the latest one prior to this
season—which his rehab team says may
or may not be related to the chondral
defect. “They were basic scopes that
could have happened regardless of the
prior injury,” says Clark. “We can’t
make any cause-and-effect conclusions
about those procedures.”
So far during the 2007-08 season,
Stoudemire’s knee has been strong.
“Knock on wood, there has never been
a swelling issue with his knee,” says
Nelson. “He gets a little stiff from time
to time, but nothing significant. It’s
normal wear and tear that even nonsurgically repaired knees have.”
Since Stoudemire’s successful return
to the court, Nelson and Clark have
fielded numerous requests from colleagues looking to obtain similar results with athletes who have chondral
defects. “When we talk to other people conducting microfracture rehabs,
we don’t really go into detail about the
actual knee rehab because everybody is
doing a good job there,” says Nelson.
“We focus more on making sure they
look at the entire body—trying to identify any imbalances that may overstress
the knee,” he continues. “We also tell
them to focus on core, balance, and
functional training—not just isolated
knee rehab.”
“From my perspective, the take-home
message is that it’s not a mysterious injury—we just have to look at what deficiencies are causing it,” says Clark.
“Typically, muscles, ligaments, and cartilage from each leg should be the same
strength, and if a deficiency exists, it
can be the proverbial straw that breaks
the camel’s back.” n
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