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Q: Knee injury severity ( Answered 5 out of 5 stars,   3 Comments )
Subject: Knee injury severity
Category: Health > Conditions and Diseases
Asked by: nelgsta-ga
List Price: $7.00
Posted: 16 Jun 2006 20:13 PDT
Expires: 16 Jul 2006 20:13 PDT
Question ID: 738856
I was hit by a car 48 hours ago and am worried about the injury
sustained to my left knee.

Immediately after the impact, I walked on the knee and felt slight
instability in my knee, but there was no immediate severe pain or

After hospitalisation, I walked on my knee to the x-ray room and
around the hospital. The x-ray came back clear for structural damage.

Eight hours after the accident, my knee had swollen severley (on the
inside of my left knee) and was stiff. I can bear weight on the left
leg, but not much, it feels unstable. I am using crutches. I can move
the knee about 70% of normal range.

I want to know what the likely injury sustained is? Whether it is an
ACL, MCL or LCL sprain or tear? Or cartlidge damage?

The swelling has subsided after 48 hours and I have a distinct pain
that runs down the inside of my knee, suggesting the medial ligament
is damaged.

What is the likely injury and treatment options? Does the fact that I
could walk on the knee and felt no immediate pain after the incident
suggest that the injury is only a severe sprain and not a complete
Subject: Re: Knee injury severity
Answered By: boquinha-ga on 16 Jun 2006 22:20 PDT
Rated:5 out of 5 stars
Hello nelgsta-ga!

I?m sorry to hear of your injury. My husband is a family physician and
an osteopath (plus, he has interest in sports medicine) so this
question is right up his alley! I had the luxury of getting a virtual
consultation for you. This answer is in no way a substitute for an
evaluation by a licensed medical professional that you trust. Here is
what I found!

- - - - - - - - - - - - - - - - - - - -


The American Family Physician (AFP), journal of the American Academy
of Family Physicians (AAFP) had a two-part article discussing the
evaluation and treatment of knee pain. Much of what I found comes from
this article. I have focused on pain resulting from injury rather than
overuse, as this seems to be more pertinent to you.

The article can be found in two parts at:

= = = = = = = = = =

?Anterior Cruciate Ligament [ACL] Sprain. Injury to the anterior
cruciate ligament usually occurs because of noncontact deceleration
forces, as when a runner plants one foot and sharply turns in the
opposite direction. . . . The patient usually reports hearing or
feeling a ?pop? at the time of the injury, and must cease activity or
competition immediately. Swelling of the knee within two hours after
the injury indicates rupture of the ligament and consequent
hemarthrosis [blood in the joint].

On physical examination, the patient has a moderate to severe joint
effusion [swelling] that limits range of motion.?

The article describes, in some detail, some of the diagnostic
maneuvers your own physician may perform to determine the joint

= = = = = = = = = =

?Medial Collateral Ligament [MCL] Sprain. Injury to the medial
collateral ligament is fairly common and is usually the result of
acute trauma. The patient reports a misstep or collision that places
valgus [inward] stress on the knee, followed by immediate onset of
pain and swelling at the medial aspect of the knee.

On physical examination, the patient with medial collateral ligament
injury has point tenderness at the medial joint line.?

= = = = = = = = = =

?Lateral Collateral Ligament [LCL] Sprain. Injury of the lateral
collateral ligament is much less common than injury of the medial
collateral ligament. Lateral collateral ligament sprain usually
results from varus [outward] stress to the knee, as occurs when a
runner plants one foot and then turns toward the ipsilateral [same
side] knee. The patient reports acute onset of lateral knee pain that
requires prompt cessation of activity.

On physical examination, point tenderness is present at the lateral
joint line. Instability or pain occurs with varus [outward] stress
testing of the knee flexed to 30 degrees. . . . Radiographs are not
usually indicated.?

= = = = = = = = = =

?Meniscal Tear. The meniscus can be torn acutely with a sudden
twisting injury of the knee, such as may occur when a runner suddenly
changes direction. . . . On physical examination, a mild effusion is
usually present, and there is tenderness at the medial or lateral
joint line.?

= = = = = = = = = =

Based upon the mechanism of your injury, a MCL tear sounds very
likely. Here is what the AFP article had to say.

?The medial collateral ligament is most commonly injured as a result
of direct lateral force to the knee (e.g., clipping in football); this
force creates a valgus [inward] load on the knee joint and can result
in rupture of the medial collateral ligament.?

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A common combination of knee injuries is known as the ?terrible? or
?unhappy? triad. A single blow to the lateral (outside) aspect of the
knee can cause three distinct but related injuries: ?(1) rupture of
the medial collateral ligament, (2) damage to the medial meniscus, and
(3) rupture of the anterior cruciate ligament."

Here is an excerpt from another article discussing the ?terrible triad?:

?ACL injuries, torn cartilage (menisci), and the ?terrible triad? are
the result of damage to the ligaments or menisci (two disks of
cartilage that attach to the cartilage of the knee and fit into the
joint to absorb shock). The anterior cruciate ligament (ACL) can be
stretched or torn. ACL injuries are common in contact sports or skiing
or as the result of a twist or fall. You may hear or feel a loud pop
when the injury occurs. ACL injuries often bring sudden pain, knee
instability, rapid swelling, and limited movement. But in some cases,
symptoms can take as long as 6 to 12 hours to occur.

The same kind of traumas that cause sprains also can tear the menisci.
Repeated squatting or kneeling also can weaken menisci, increasing the
risk of injury. Swelling may happen immediately or appear within 24
hours. Continuing pain and a clicking or locking with knee movement
are other symptoms of torn menisci. Once the menisci are torn, the
knee may buckle or lock without warning. Wearing a brace during
activity can help protect the knee from further injury, but surgery
may be needed to remove pieces of torn menisci.

The terrible triad is a combination of torn menisci, ACL injury, and a
sprained ligament at the inner side of the knee?all from a single
blow. Damage this serious usually requires surgery.?

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You mentioned that you had normal x-rays, but x-rays are not the best
type of imaging for detecting soft tissue damage. ?Because most
patients with knee pain have soft tissue injuries, plain-film
radiographs generally are not indicated.?
(  The AFP article
frequently mentions using MRI as a means to rule out ACL, MCL, and
collateral ligament damage.

The following article discusses the uses and benefits of
using MRI in knee pain. In particular it discusses detecting injuries
to the menisci, ligaments, and tendons of the knee.

- - - - - - - - - - - - - - - - - - -


Treatment of knee pain depends upon a number of factors. Among those
are the relative health of the individual, his or her activity level,
and the stability of the joint. Many of the soft tissue injuries I?ve
mentioned above require surgical intervention. Most of them can be
addressed by arthroscopic surgery.

Here is a nice article from the American Academy of Orthopaedic
Surgeons that describes arthroscopic knee surgery.

If your problem is truly just a severe sprain, then this can be
addressed with anti-inflammatory medications (such as naprosyn or
ibuprofen), physical therapy, and possibly temporary bracing. The
complete treatment plan would need to be determined by your own
personal physician after a thorough history and physical examination.

- - - - - - - - - - - - - - - - - - - - -


So, from what you?ve described and what I?ve researched, it seems
likely that you have an injury to your MCL. Injuries to the ACL and
medial meniscus cannot be ruled out completely without further
examination and possibly MRI. You?ve mentioned that your knee feels
?unstable,? and if an examination confirms this, surgery may be the
best treatment option. Be sure to see your personal physician for a
more thorough evaluation.

- - - - - - - - - - - - - - - - - - - - -

I hope that you find this information useful and that you can begin to
feel better soon. As I?ve said before, this answer is not intended to
substitute for an evaluation by a qualified medical professional that
you trust. If you have any other specific questions and concerns, be
sure to discuss them with your own physician as well. If you have any
need of further clarification, please let me know how I can help. Good


Search strategy:

Online search
Consultation with my physician husband

Search terms:

knee pain differential
medial knee pain differential
terrible triad knee
knee laparoscopic surgery
nelgsta-ga rated this answer:5 out of 5 stars

Thankyou so much for such a great answer! It was my first Google Answer experience!

I had an MRI before I read the answer, and I have suffered the
'terrible triad' - you were spot on!

Thanks again!

Subject: Re: Knee injury severity
From: ronson-ga on 17 Jun 2006 11:22 PDT
I suggest you ask a doctor.
Subject: Re: Knee injury severity
From: dragon_2-ga on 18 Jun 2006 21:41 PDT
Physical Therapy may be a better option than immediate conclusion that
surgery is needed.

Depending on severity of injury and which structures are involved,
functional stability training may be a better option.

If you go see a surgeon, they make money by doing surgery.
If you go see a therapist, they make money by doing therapy.

Be sure of of motives of whomever you consult with.
Subject: Re: Knee injury severity
From: boquinha-ga on 18 Jul 2006 19:16 PDT
Thank you so much for the nice comments and 5 stars! I'm so glad that
your first experience with Google Answers has been a good one. Enjoy
the site--it's a lot of fun and has a wealth of information! Thank you
again! And I hope you're feeling better.


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