By Catherine Lester

I ran my first marathon in Rome in April, albeit slowly. I had never run further than 10km as of December last year.  My dad asked me if I was sure I should be running – in 2008 I injured my left anterior cruciate ligament (ACL), medial collateral ligament (MCL) and both menisci skiing and in 2012 I ruptured my right ACL.  Both have subsequently been reconstructed and rehabilitated.  My left knee has had a lateral meniscal debridement and a failed medial meniscal repair followed by a meniscectomy.

What are the risks associated with the repetitive load of marathon training in a previously injured knee? Wearing my ‘SEM Clinician’ rather than my ‘athlete’ hat, what do we tell our patients? 

The May BJSM featured the old knee in the young athlete and particularly focused on pivoting sports.(1)  Whilst perhaps not relevant to marathon running, their recommendations were to allow the patient to be the boss of their decisions, to embrace shared decision making in deciding on return to play and to present risk and information that is relevant to the athlete.(1)

Recreational running is on the increase.  Spend a day either spectating or working medical support at the London marathon and you will quickly learn that not all marathon runners are equal.  Running a marathon attracts avid charity fundraisers, people coerced by friendly ‘peer pressure’ and in some instances it has become a sporting event ‘everyone’ would like to do at least once.  Runners come in all shapes and forms and the average age is getting older.(2)  Because of this variable body shape and increasing age it is easy and almost logical to expect to see an increased incidence of osteoarthritis (OA) secondary to the repetitive joint load involved in training and completing a marathon.

If you sustain an ACL injury you will have a greater chance of developing OA down the line.(3)  It is a well-known complication with a prevalence of 10-90% at 10-20 years following an injury.(4)  But what are the risks of OA in a previously injured knee when running a marathon?

A recent systematic review by van Meer et al.(3) looked at both tibiofemoral and patellofemoral OA after ACL injury. Their review concluded the medial meniscal injury/meniscectomy is a positive predictor for tibiofemoral OA and OA of the knee joint where the compartment was unspecified.  The same cannot be said for lateral meniscal injury/surgery where there is conflicting evidence. In addition, there was conflicting evidence on the development of osteoarthritis in an ACL reconstructed knee versus a conservatively managed cruciate ligament.(3)

The knee is the most injured structure during distance running accounting for up to 42%(5) of running injuries.  Traditionally this has been iliotibial band and patellofemoral joint injuries however meniscal injuries are starting to be more common.(2)  Previous injury and running mileage over 40 miles or more per week have been proven to be significant risk factors for developing a running injury,(2) but this mileage does not necessarily cause OA.  It is important to note that other research suggests that 40 years of running 20-40 kilometres weekly does not lead to OA in individuals without previous injury(6). Leech et al. wrote an editorial citing ten papers and concluded that overall there is insufficient evidence that recreational running contributes to the development of OA.(7)

A literature search revealed an article entitled ‘To run or not to run: A post-meniscectomy qualitative risk analysis model for osteoarthritis when considering a return to recreational running’.(8)  The author summarised the predictors for OA into a table and while meniscus surgery and injury were included so were age, female gender, body mass index and pre-existing radiographic or arthroscopic evidence of OA.(8)

They concluded their paper with two phrases which could be adopted into one’s clinical practice that symptomatic OA in a patient following meniscal surgery ‘is a probability and not a certainty’ and ‘runners are a self-selecting group’, in other words generally those who experience significant symptoms choose not to partake in long-distance running.(8)

In summary, the risks of developing osteoarthritis of the knee are complex and often multi-factorial.  I am at risk and am likely going to develop OA, certainly radiographic even if not symptomatic, particularly in my left knee, but did running Rome marathon increase this risk significantly?  I think it is unlikely, as there is insufficient and conflicting evidence to support this.  This experience will further reinforce my current clinical practice; that ‘never’ is very rarely an answer.  As Sport and Exercise Medicine clinicians I feel we need to be educating patients in order for them to make their own risk assessments and I believe that often the gained benefits of taking part in physical activity of any nature outweigh the risks in most scenarios.

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Catherine Lester is a speciality registrar in SEM currently based in Cambridge. She works with Bedford Rugby club and the GB and England women’s hockey teams under the CMO.

Farrah Jawad is a SEM registrar in London and co-ordinates the BJSM Trainee Perspective blog.

References

1. Ardern CL, Khan KM. The old knee in the young athlete: knowns and unknowns in the return to play conversation. Br J Sports Med. 2016;50(9):505-6.
2. Fields KB. Running injuries – changing trends and demographics. Curr Sports Med Rep. 2011;10(5):299-303.
3. van Meer BL, Meuffels DE, van Eijsden WA, Verhaar JA, Bierma-Zeinstra SM, Reijman M. Which determinants predict tibiofemoral and patellofemoral osteoarthritis after anterior cruciate ligament injury? A systematic review. Br J Sports Med. 2015;49(15):975-83.
4. Lohmander LS, Englund PM, Dahl LL, Roos EM. The long-term consequence of anterior cruciate ligament and meniscus injuries: osteoarthritis. Am J Sports Med. 2007;35(10):1756-69.
5. Taunton JE, Ryan MB, Clement DB, McKenzie DC, Lloyd-Smith DR, Zumbo BD. A retrospective case-control analysis of 2002 running injuries. Br J Sports Med. 2002;36(2):95-101.
6. Konradsen L, Hansen EM, Søndergaard L. Long distance running and osteoarthrosis. Am J Sports Med. 1990;18(4):379-81.
7. Leech RD, Edwards KL, Batt ME. Does running protect against knee osteoarthritis? Or promote it? Assessing the current evidence. Br J Sports Med. 2015;49(21):1355-6.
8. Baumgarten B. To run or not to run: a post-meniscectomy qualitative risk analysis model for osteoarthritis when considering a return to recreational running. J Man Manip Ther. 2007;15(1):E1-E15.