Sports Medicine Research: In the Lab & In the Field: Fear of Reinjury or Knee Pain May Inhibit Full Return to Sport Following an ACL Reconstruction (Sports Med Res)


Tuesday, September 3, 2013

Fear of Reinjury or Knee Pain May Inhibit Full Return to Sport Following an ACL Reconstruction

Fear of reinjury (kinesiophobia) and persistent knee symptoms are common factors for lack of return to sport after anterior cruciate ligament reconstruction.

Flanigan DC, Everhart JS, Pedroza A, Smith T and Kaeding CC. Arthroscopy. 2013; 29(8) 1322-1329.

Take Home Message: Following an ACL reconstruction, persistent knee pain and/or fear of reinjury may contribute to whether or not a patient will return to their preinjury level of activity.

The purpose of an anterior cruciate ligament (ACL) reconstruction is to restore knee kinematics and anatomy, improve knee stability, and allow an athlete to return to their preinjury level of activity. However, in reality less than half of patients undergoing an ACL reconstruction will return to their preinjury level of activity. A better understanding of why these athletes do not return to their preinjury level of activity would allow clinicians to design more appropriate rehabilitation and counseling programs to mitigate factors that prevent the athlete from returning to their desired level of activity. Therefore, Flanigan and colleagues completed a retrospective cohort study to determine the patient-reported reasons for lack of return to sport after an ACL reconstruction. The authors identified 171 patients who received an ACL reconstruction from two surgeons between 2007 and 2008. A total of 135 patients completed a telephone interview (67 men, mean age ~ 29 years, 123 primary reconstructions, 12 revisions, time since surgery: 12 to 25 months). Patients answered questions about their previous and current activity level, as well as factors that contributed to their activity level. Overall, 62 (46%) returned to their preinjury level of activity (returners) and 73 (54%) did not (non-returners). A returner was more likely younger than non-returners. Most of the non-returners were recreational or high school athletes (only 8 athletes completed at collegiate or professional levels). The first and second most commonly cited reasons for not returning to preinjury level of activity was “persistent knee symptoms (pain, swelling, stiffness, instability, or weakness)” (50/73 non-returners, 68%) and fear of reinjury (38/73, 52%) respectively. Of the 50 patients who responded to having persistent knee symptoms, 25 (50%) patients also cited a fear of reinjury as a reason for not returning to their preinjury level of activity.

Overall, the data presented above should be extremely useful to clinicians. If an athlete expresses a wish to return to their preinjury level of activity, clinicians can focus on controlling knee symptoms (pain, swelling, stiffness, instability, and/or weakness) as well as discuss their fear about reinjury throughout the rehabilitation process. Although not an outcome measure in this study, it would be interesting for future research to see how much one factor influences the other. Perhaps if the “persistent knee symptoms” were resolved the patient may have an increase in confidence thus reducing their fear of reinjury. While this data is interesting, the study was limited by its inclusion of different activity levels and patients who underwent an ACL revision surgery. Patients who underwent an ACL revision surgery would have at least 1 other surgery during which the joint was subject to extra trauma. This would definitively increase the likelihood of the patient developing “persistent knee symptoms.” Further, these patients would also have failed their primary reconstruction which may lead to an increase in fear of reinjury. The inclusion of varying levels of participation is also of concern. Patients who compete for recreation may be more willing to change their activity level to meet their particular symptoms but elite athletes often do not have this option. This study and several others we’ve had on Sports Med Res (SMR) before (see below) highlight that a fear or reinjury is an important issue that we may need to address if we are to achieve our goal of returning our patients to their pre-injury level of physical activity.

Questions for Discussion: Do you believe the patient’s fear of reinjury was born from their current symptoms? How do you approach this throughout the rehabilitation and return to sport process?

Written by: Kyle Harris
Reviewed by: Jeffrey Driban

Related Posts:
Fear of Re-injury in People who have Returned to Sport Following ACL Reconstruction

Flanigan DC, Everhart JS, Pedroza A, Smith T, & Kaeding CC (2013). Fear of reinjury (kinesiophobia) and persistent knee symptoms are common factors for lack of return to sport after anterior cruciate ligament reconstruction. Arthroscopy, 29 (8), 1322-9 PMID: 23906272


Callie Jedrzejek said...

This study was very interesting to me and brought my attention because as an athletic trainer, there are multiple times I have seen an athlete nervous about returning to full participation after and ACL injury. In the study, did they look at what type of graft the patient had, and maybe there is a difference in the feeling of stability where the patient feels more comfortable then other grafts? Maybe that is something they could think about in another study in the future. Also with the patients who are afraid but still return to play, due to their timid and fear do they alter their gait at all and that could potentially cause more knee problems and worse come they re-tear their ACL or tear the other one?
Overall though I thought the article was well written and easy to read.

Callie Jedrzejek ATC, LAT

Jake Meyer said...

This article is of interest to me because I am currently working with an ACL-R patient who is hesitant to trust the new graft while we are working on pushing him to begin normal movements.

After reading this, some thoughts come to mind. When I think about an ACL injury and the surgery that comes afterwards (most of the time because of the population I work with) the first thing that comes to mind is the consequence of arthrogenic muscle inhinition (AMI). The knee joint, alone, has been reconstructed and is arguably the most stable it will ever be immediately after surgery. But, in the eyes of the patient, they have no muscle tone in their thigh, they cannot contract their quads, and they are in pain.

The reality of the situation is that something could be happening neurologically to cause the quads to shut down and/or undergo some kind of change. This is the most challenging aspect of rehab to overcome and return to normal functional activity and full participation in athletics.

To me, it is because of this AMI and potential change in the quadriceps quality that the patient may suffer from kinesiophobia. It is common for athletes to return to sport at around 85% of full strength compared to the uninjured limb. It has been theorized that there could be a change in muscle fiber type with a relative decrease in the fast-twitch fibers and a relative increase in slow-twitch fibers. This seems like it could be a reason that patients may regain some quad strength, but function in a constant fatigued state. I am interested to follow how the idea of kinesiophobia in ACL-R population changes with the development of research and techniques to regain normal quad activation and function following ACL-R.

Kyle Harris said...


Great questions, thank you for posting! The answer to both of your inquiries is unfortunately no. The graft type was not discussed but I believe your thought is well rooted. Many studies looking at different graft types and surgical procedures exist but this was not a focus of the current study. I do agree with you though that this could be a factor that needs to be assessed further. I believe that this may eventually lead clinicians to an optimal surgical and rehabilitation protocol to optimize return to play. The study also did not address an alterations to the patient's gait patterns. This too could be a significant factor but I agree that the impact of kinesiophobia on this must be explored more in high quality studies first. Interesting points, is this change in gait pattern something you have seen in your practice?

Kyle Harris said...


Great post. You have had a very interesting experience with you patient that helps insight the conversation. I too agree the future of kinesiophobia research will greatly inform clinicians everywhere. I do think though that a difficulty with this line of research will be the ever changing target of the optimal ACL reconstruction technique. What do you think. Will the fact that ACL reconstruction techniques are every changing (although minorly) will impact the applicability of kinesiophobia research?

Jake Meyer said...


This is an interesting question. However, it seems that regardless of the graft type, AMI is always present after reconstructions, which makes me think that it is the root of all of the difficulties surrounding ACL-R rehabilitation. For some reason my gut tells me that graft type will not have as large of an impact on kinesiophobia as AMI does. This is largely anecdotal, but there is some literature that supports the notion that there is little difference in patient-reported outcomes comparing graft type.

Kyle Harris said...


Great feedback. I think arthrogenic muscle inhibition would definitively play a factor in kinesiophobia. I think your thought process will also be supported by an upcoming post of mine on September 25th which looks at a study by Mattias Ahlden. In the study they look at both subjective and object clinical outcome of single and double bundle ACL grafts so stay tuned for that. If this is true, then perhaps AMI is much more of a factor in returning an athlete to play. How do you address this issue with you patients?

Post a Comment

When you submit a comment please click 'Subscribe by Email" (just below the comments) or "Subscribe to: Post Comments (Atom)" (at the bottom of this page) if you would like to receive a notification when another comment has been submitted to this post.

Please note that if you are using Safari and have problems submitting comments you may need to go to your preferences (privacy tab) and stop blocking third party cookies. Sorry for any inconvenience this may pose.