Dear Vladimir,

The anterior cruciate ligament (ACL) is the most commonly injured of the major knee ligaments. Patients with ACL injury have variable knee instability that may limit even ordinary daily activities. In this way, we observe that this type of injury can affect both athletes and nonathletes. Long-term morbidity is common with sequelae including osteoarthritis and secondary meniscal tears. A primary role of MRI in the management of the patient with an ACL injury lies in allowing confident diagnosis or exclusion of a tear in patients with equivocal physical examination findings. It should be emphasized, however, that ACL injury management is critically dependent on accurate diagnosis of other coexisting knee internal derangements, in particular tears of the lateral collateral ligament (LCL), posterior cruciate ligament (PCL), and the menisci. Patients with combined LCL/ACL or PCL/ACL injuries often have profound instability requiring aggressive surgical management. In the instance of a coexisting LCL tear, intervention may be hastened as LCL injuries are optimally repaired within 1-3 weeks. Relevant to the discussion above, Vincken et al point out that it is the evaluation of the knee joint as a whole (the composite diagnosis) that is central to appropriate selection of patients for therapeutic arthroscopy. The high reported composite sensitivity and specificity of knee MRI (87-94% and 88-93%, respectively) indicates MRI should serve well in this role. A study by Thomas et al concluded that while MRI may be overused in high-probability ACL-meniscal injury settings, a negative MRI largely excludes derangements that will benefit from arthroscopy. While accurate in the diagnosis of ACL injury, MRI findings are not helpful in ruling in or ruling out knee instability. Evaluation of instability enters strongly into the decision to opt for conservative or surgical treatment, and this remains a clinical assessment. We must observe that part of the problem stems from the fact that the term is a radiology one. By that it mean that it is based on the fibers of the anterior cruciate ligament and what percentage of them are torn. Obviously in a complete tear, the ligament and all of its fibers are torn. But in a partial ACL tear, 30% of the ligament fibers might be ruptured, or 80% might be torn. It is based completely on the MRI images. And as such, a “partial” ACL tear diagnosis is only part of the story. The most important in this case, is verify whether or not the ligament is functional. Note that previous studies whcih deal about this subject argue that an athlete can have 50% of the ligament intact and still have a stable knee, or they can have her knee give way with cutting or changing directions even though 50% of the fibers (as estimated by MRI) are intact. When the initial injury occurs, some of the fibers might become stretched out, despite remaining intact, so in essence they are not providing the necessary stability to the knee. There are some signs that a ligament with some fibers still intact is essentially nonfunctional, such as a specific pattern of bone bruising that you see on MRI.

In addition, I recommend the following material (see LINK).

I hope this helps.

http://www.hindawi.com/journals/aorth/2015/928301/

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3415702/

The presence of degenerative changes in a young adult is a cause of deep concern. But it should not increase the risk of further ACL injury. Intact, due to pain and apprehension the athlete may not put that extra stress on the knee, thus preventing ACL injury!!

It is not surprising to find degenerative changes of ACL in young athletes. Furthermore, if such changes exist this makes ACL more vulnerable because its strength, elasticity and durability reduce. So in similar cases further training in elite sports should be seriously discussed. Perhaps, change of sports kind should be considered, i.e. from athletics to swimming. 

Degeneration in young athletes are consequence of bad preparation, gait and technique that reflects on the coach and the abilities that he/she has. As soon as they are present they are not reversible. ACL injury could be of a higher risk only if the athlete continues to try to perform as high as it is possible and so it will not be possible to protect the joint or when he/she will not correct the gait. The usual injury is partial tear of the fibers and this can result to minute instability which can result to gradual progression of the degeneration. This instability will be at the peak of the function and possibly will not be possible to be detected in normal movements of the joint. In case of degeneration within the joint is not only the ACL that is at risk but also the meniscal injuries can become more common resulting to further aggravation of the secondary arthritic changes.

The degeneration may also be due to poor landing posture.  The valgus position has been implicated, though with some controversy.  Here's an article talking about that. 

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3647681/

Dear Marcelo Guimarães Silva, 

Thank you for your detailed discussion about knee ligaments and MRI, and thank you for articles that you attached. I ll do my best to check them immediately when the time allows me.

In the end you just opened new question, with the partial ACL injury, during manual testing knee can be stable... but in sports we have much bigger forces acting, in this case, on ACL. I am not a surgeon, but I am interested to know the answer. With partial ACL injury, surgery is suggested or not... since the athlete competing with injured ACL, but still stable knee, is under high risk of complete injury with other associated injuries....

Again, every discussion is welcome.

Vladimir

Dear Raju Vaishya,

Thank you for your answer. 

But even if the ACL is under degenerative changes, it doesn't increase possibility of it's on injury?

Since we are talking about young athlete who is 17 years old, really perspective, and just entering into professional sport... Its almost impossible that during further career the load will be decreased....

Sincerely,

Vladimir

Dear Panayot Tanchev,

Thank you for concrete answer. But unfortunately changing the sport with professionals.. is almost impossible....

Dear George Zafiropoulos, 

Thank you for your answer. As you probably know, in professional sport, majority of the activities are performed on high level in order to achieve maximal results. So it is hard to decrease the volume/intensity in that manner... temporary yes... but permanently unfortunately no. With the rest of your answer about gait technique, bad preparation etc I completely agree. But those athletes "knock on my door" with those kind of diagnoses... and for me it was new to have so many young athletes with degeneration of different elements of knee.

Dear Timothy Hui,

Thank you for discussion, I ll read the article.

Regards,

Vladimir

Presence of degeneration as it is mentioned, is the result of increased loading within the joint. This increased loading is destroying the articular cartilage and it can be caused by bad muscle or ligament balance. Muscles and ligaments work better when they warm up and the proprioception is geared up. So the person leading the training is responsible to control it. If degeneration is present the ligaments and mainly the ACL can be considered partially damaged  (arthroscopic finding "attenuated" 

Seem that part of the answer is not appearing- apologies for this

Continuing

If degeneration is present the ligaments and mainly the ACL can be considered partially damaged (arthroscopic finding "attenuated ligament") and continuation of the same activities under the same conditions and the same trainer can lead to further injury to ACL (further partial or complete rupture). Change of any of these three factors or all of them (activities, conditions, trainer) can help matters.

It is known that some athlete look only the shortcoming of their career and do not obey Doctor's Orders. A professional athlete has to show and promote professionalism. One of professionalism's criteria is "looking after own Health". A professional athlete has to have self-respect, self-discipline and self-control. Must be able to obey for the own good the instructions and indications given to him and mainly if these are of the treating doctor or health-worker in general. An athlete who is not prepared to "look after self" and leaves the own ambitions and emotions to control then he is loosing the title "professional" and is an amateur who wants to follow with "lust" a sport without indicating any care of the own well being. Such a person has to be placed responsible for the damage created by the self to the body and this may considered self-harm. So statement as "changing sport is impossible" is not compatible to a professional individual