Developed 7-23-00
Revised 8-17-00
My leg is weak
My knee doesn't feel quite normal
MRI indicates a partial tear
Arthroscopy reveals a partial tear
OS thinks I have a partial tear
I have a partial & stretched ACL ?
OS wants me to only rebuild muscles
OS wants me to wear a brace for sports
I'm afraid my knee may go out
My knee seems great
Will my knee be okay ?
I had another knee event
My OS says he may recommend reconstruction
What should I do ?
Should I get a second opinion ?
So now what ?
How do I convince the OS I want a reconstruction ?
How do I avoid a reconstruction ?
All I want to do is get back to my sports !

Welcome to the Limboland of ACL Partial Tears !  You have plenty of company. This is not necessarily a bad place to be but it can be temporary depending on many factors - extent of your tear, how stretched it is and your own body-knee configuration. Here's my spin on this limboland---
An ACL deficiency is not always identified beforehand and may only be discovered during arthroscopy to repair cartilage. In other instances, an ACL deficiency may be suspected but the OS may not be convinced that it is a significant loss of ACL functionality and may not recommend arthroscopy as a way to find out the extent and/or do a reconstruction. If the ACL was suspected to have lost total functionality or was identified in an MRI as completely severed, well then the decision regarding reconstruction or not has more to do with the OS's assessment of your level of sports activities and/or knee event history as to whether or not he would recommend an ACL reconstruction.

While an MRI is much better than an xray in identifying internal deficiencies to the knee, it still is not 100% accurate in identifying everything. Usually, when the ACL is fully torn, there is the absence of seeing a line (ACL) where it should be when viewing the MRI and that input is of major benefit to an OS because a reconstruction would then be considered. An MRI is much better at identifying cartilage tears and fully severed ACLs as it is in determining partial ACL tears. It also cannot identify the extent of the partial tear - 25%, 50%, 75%, etc. So, the MRI is only "partially" helpful in regards to helping an OS decide what to do for a suspected ACL deficiency.

Here's the other spin from the Operating Room (OR) scenario. Let's say that your OS does not know you have an ACL deficiency but you have a cartilage tear that needs to be repaired or cutout. Another possibility is that you have a cartilage tear or other deficiency that requires arthroscopy and the OS suspects you have a partial ACL tear but indicates he is going to take a look at it better during arthroscopy.  Many times when an OS sets up the schedule for how long he will be in the OR for you, there are other patients in wait for the OR and OR "time is money". So, for a cartilage tear, an OS will normally need about an hour of OR time. But if he's "prepared" to do a cartilage tear and a reconstruction, an OS will generally schedule the OR for 2 1/2 hours and take care of both. Of course, this schedule is somewhat  flexible but if he was not expecting to do a reconstruction and did not talk to you about the options involved with a reconstruction (for a partial or a severed ACL), chances are that an OS will not make the decision for you without first having a discussion with you about it in his office - and then there is the scheduling time for the OR and any other preps he would have had to have ready for the reconstruction.

A partially torn ACL is not always picked up as looseness during an OS's self exam. Many are but some are not. That's why an MRI is useful in assisting the OS in making a diagnosis and establishing what course of action should be taken.  If it is suspected you have a partial ACL tear and have not severed it, then the OS may be reluctant to recommend a reconstruction as the first course of action. This is because there are probably plenty of individuals out there that have been able to rehab to full muscle strength and with the use of a custom sports brace are able to return to sports.  Depending on your activity level, what percentage ACL tear you really have, how stretched the ACL is and your own individual body-knee configuration, you may have many years of  sports activities in  you (probably with the use of a custom sports brace) and your knee may be fine for all those years !       Then again, it may get reinjured in 5 years or maybe much sooner. That's why I call this the Limboland of ACL Tears.

An OS may recommend a reconstruction for a partial tear if his diagnosis indicates that you have lost very significant or total ACL functionality and that you need to recover your lost functionality for your level of activities. An OS may not recommend a reconstruction if he is not convinced that either your ACL functionality is lost or that your quality of life will be significantly altered. In my opinion, an OS forms his diagnosis on at least the following factors: His self-eval, MRI, possibly other qualifying tests, your knee-event history and your activities level (ie. cutting type sports like basketball, tennis, etc).

So, what does the percentage of ACL tear have to do with anything ?  Depending on the percentage tear, there have been studies that indicate based on statistics, what your chances are for reinjury.  Even with the use of a custom sports brace, there is chance for reinjury. A journal article I have indicated that a 25% partial ACL tear has a minimal chance of reinjury within 5 yrs. Whereas, a 50% ACL tear has a  50% chance of reinjury within 5 years and a 75% ACL tear has a 87% chance of reinjury within 5 years. Of course, if the ACL is also stretched, well then the chance of reinjury may be a moot point depending on your already lost ACL functionality. The only way an OS can make an accurate assessment of what percentage ACL tear you have is thru arthroscopy. Therefore, it's sort of a guessing game as to the extent of a suspected tear if determined by an MRI or a self-eval.

My Experience With A Partial ACL Tear
My OS had me go for an MRI. I believe his self-eval did not conclude significant looseness but he had drained my knee due to the swelling and since there was a blood tint in the fluid - something had happened. The MRI indicated that I had a cartilage tear and my OS recommended arthroscopy. It was during the arthroscopy that a 50% ACL tear and stretched condition was identified. I was about 40 yrs old when this happened.

My OS did not recommend a reconstruction at that time, although, he did say that I would not be able to play basketball, tennis, etc. He recommended I fully rehab muscle strength and I started to go to therapy 3 times a week. I eventually reached full muscle strength and was tested with the Biodex machine for confirmation. This took about 3 months post-op.  My OS then had the Physical Therapists (PTs) test my knee on two different occasions using a KT-2000 unit. This is a small hand held unit that is strapped onto your upper and lower thigh while you rest on one of the tables with the legs straight out. The idea is to relax while the PT moves the unit up and down and checks to see what the unit indicates for relative looseness of the knee joint - upper and lower leg movement. Then the good leg, if you have a good leg, is checked and the measurements are compared to each other. This test, rather crudely, tries to quantify the self-eval test that the OS performs from his own experience. Based on my successful rehab to full muscle strength and I guess decent KT-2000 measurements and the OS's self-eval, my oS let me return to all cutting type sports but I had to wear a custom fitted sports brace for those activities.

I was told that I had a 50% ACL tear and had a 50% chance of reinjury in 5 years. This was based on the journal article my OS gave me for reference.  I had no knee deficiencies at all for 8 years until I somewhat slacked off my single leg exercises to maintain muscle strength and I did a twisting fake move on the basketball court resulting in severing the ACL. I have no regrets. I had 8 great knee years of no problems.

I then exited the Limboland Of ACL Partial Tears and ventured into the OR once again but this time for a patella autograft reconstruction. Ahhh ! But that is another story and elsewhere in this website.
Link To ACL Reconstruction Indications (Orthopaedic Site)