Nabil Fekir was expected to move to Liverpool over the summer for 52.8m pounds with a 5 year contract agreed upon prior to joining up with the French National team for the World cup (spoiler alert: they did well). However, during his physical in June Liverpool’s medical staff found some warning signs that indicated “increased wear on his cartilage” in his injury plagued right knee, concerning enough that they sought a second medical opinion in July. After that 2nd opinion, Liverpool tried to re-negotiate for a lower fee but the transfer fell through.
The entire saga left Nabil Fekir looking at Liverpool like:
In this piece, I’ll delve into why this increased wear in the right knee cartilage of Nabil Fekir triggered Liverpool’s concerns, how he got to that point, and what it means for Nabil Fekir going forward.
Lets start at the beginning of his right knee injury history…
I. 2015/16: Nabil Fekir ACL Rupture
Early into September of 2015, Nabil Fekir ruptured his right ACL (anterior cruciate ligament) during an international match against Portugal.
ACL stands stands for “anterior cruciate ligament” and is a major stabilizer in your knee during any forwards, backwards, or rotational movement. Think of it like a rubber band that connects your thigh bone (femur) to your shin bone (tibia) and keeps the knee joint from moving outside its intended normal range of motion.
Here’s what the ACL anatomy looks:
Nabil Fekir underwent surgery to repair the torn ACL, often termed an “ACL reconstruction”. Check out this work-safe video of an ACL reconstruction:
There’s been some concern that the type of graft used for Nabil Fekir (the surgeon used an allograft which is tissue taken from a cadaver) opened him up to increased risk for subsequent problems or re-injury. This is in contrast to an autograft which is taken from the person’s own body (most commonly from the patellar tendon or hamstring).
Although allografts are typically used in middle-aged athletes who engage in low-impact sports, they have not been found to be inferior to autografts. In fact, no particular graft has proven superior or clearly demonstrated superior functional outcomes (click here, here, here, and here for more info).
What’s far more concerning to me was how quickly Nabil Fekir returned to play. He came back in early April 2016, after missing 39 games for Lyon – a mere 7 months after his injury. That’s nearly 3 months quicker than the average for professional soccer players after ACL injury.
It’s certainly possible that Nabil Fekir is an outlier, recovered much quicker, and got back earlier. That does happen.
However, evidence shows that early participation and accelerated ACL protocols do carry some risks. Athletes in accelerated rehab programs may have ongoing abnormal motion and relative weakness for up to 22 months following surgery, in addition to an increased risk for knee osteoarthritis (click here and here for more info).
This is in addition to key inherent risks after ACL injury, regardless of how quickly or slowly you return.
These include, first and foremost, nearly a 25 percent chance of re-rupturing the same ACL after surgical repair . It’s no coincidence that prior ACL injury is the best predictor for future ACL injury.
Secondly, the risk of rupturing the other side (“contralateral”) ACL after surgical repair is upwards of 20.5 percent! Bio-mechanics, proprioception, and compensation are a love-hate relationship.
Lastly, there’s evidence of side-to-side deficits potentially lasting two-plus years and asymmetry has been associated with an increase in injury risk for high speed and cutting sports like soccer.
However, the overall outcomes on ACL repair in elite athletes is pretty dang good. Recent high level evidence on return to sport after ACL surgery has shown that nearly 83% of elite athletes return to sport following an ACL surgery and most performed comparably to non-injured counterparts.
Regardless, Nabil Fekir did come back and that right knee continued to give him some problems…
II. 2016 and 2018 Right Knee Injuries
In late August 2016, Nabil Fekir suffered an undisclosed injury to his right knee during Lyon’s 4- 2 defeat vs Dijon. What we do know is that this injury required an operation and Nabil Fekir missed 23 days and 3 games for Lyon.
He was able to play through the rest of the season without incident and he played quite well, making 49 appearances in all competitions for Lyon with a stat line of 14 goals and 12 assists for the season.
During the following 2017-2018 season, Nabil Fekir was able to make it through unscathed until he suffered a “knee contusion” in late February and then underwent an “arthroscopic lavage” which means the knee joint was washed out to clear out any loose or irritated “debris”, most likely cartilage.
Here’s a visual and note that this picture includes a “trimming instrument” in addition to an “irrigation instrument” because arthroscopic debridement (trimming or cutting out of irritated tissue) is often done alongside a lavage (washing out):
These instruments are inserted through tiny incisions (“portals”) that make the surgery less invasive and easier to recover from.
This procedure was done in preparation for the World Cup so any of that loose debris wouldn’t cause him to miss time due to swelling and pain and potentially fall out of favor. These “clean-out” procedures are relatively common after an ACL rupture and speaks to how the post-repair changes can lead to cartilage issues.
All in all the, the contusion and arthroscopic lavage caused Nabil Fekir to miss 35 days and 7 games, returning early in April.
In a vacuum, these injuries aren’t a big deal. However, in conjunction with his previous ACL tear, these are two additional insults that may have exacerbated ongoing changes in his mechanics, tissue quality, and loading at the right knee joint. Additionally, the second procedure speaks directly to ongoing cartilage changes within the right knee.
These changes very likely contributed to the problem that led to Liverpool re-considering their initial bid…
III. 2018 Failed Transfer: Worn Out Right Knee Cartilage
The inflection point in the Nabil Fekir transfer saga were the results of his MRI. L’Equipe had a physician on record who stated:
“In this case, what poses a problem no doubt, is the wear of cartilage.
So what exactly does that mean? Lets start with some anatomy
A. The Knee Joint
The knee joint is comprised of the upper leg bone (femur), the shin bone (tibia), the patella (kneecap), and two types of cartilage (articular cartilage and the meniscus). Take a look:
Generally, cartilage serves to reduce friction and dampen force. The first type, articular cartilage, covers the ends of the femur (thigh bone) and tibia (shin bone) and the inside of the patella (kneecap). The second type of cartilage, the meniscus, is a dual-crescent shaped pad that sits between the femur and tibia:
Knee cartilage has normal age related changes due to the constant loading that it endures. That’s perfectly normal. I wager that if you took an MRI of most active individuals over the age of 25, you could find some meniscal wearing.
However, the concerns and doubts creep up when you see an increased rate of degeneration on that cartilage which can lead to….
B. Knee Arthritis
When the articular cartilage and/or meniscus have deteriorated to a certain extent, the knee is considered to have “mild arthritis”.
I like to think of the knee cartilage like a shoe insole and knee loading like taking a step. Normally, the force from taking a step is distributed evenly across the cushioned insole of your shoe. However, if you start to walk differently (lets say you start to favor the inside of your foot, for whatever reason), then the inner part of the insole is going to wear out much quicker.
It’s the same concept for the knee cartilage. Repetitive force on the same spot leads to increased wearing out of the cartilage on that spot.
It’s very likely that the ACL rupture in 2016 was the root cause for Nabil Fekir developing this “worn out cartilage” in his right knee. There are two main purported reasons:
- The traumatic impact to the knee during the initial ACL rupture initiates a chemical degeneration process of the knee cartilage (click here, here, and here for more info).
- An ACL injury, even after it’s been repaired and the ligament is providing optimal stability, can change the mechanics and loading patterns at the knee. This results in accelerated wear and tear and irreversible changes on the knee cartilage (click here, here, and here for more info).
Combine that with other potential risk factors:
- Accelerated return from ACL rupture in 2016
- Two other injuries to that same knee
- Repetitive and constant loading at the knee (running, jumping, cutting, kicking, etc etc)
And that’s a recipe for developing mild arthritis early on in your career.
Further, that mild arthritis can gradually evolve into moderate and severe arthritis where the bones are actually rubbing against each other, this is called osteoarthritis (OA).
Here’s an anatomical representation:
And what it looks like on x-ray (notice the decreased space and side to side asymmetry):
When the Liverpool medical staff saw that worn out knee cartilage, it tilted their risk/reward calculation. Here’s what the physician had to say:
It’s a risk factor. It can cause pain, functional issues and eventually a lesser resistance to impacts.”
Based on that new medical concern, it makes sense that Liverpool’s valuation changed, especially for a player they would be investing a huge sum and 5 years into.
Additionally, there are long-term ramifications that Liverpool had taken into account as well…
IV. Long-Term Ramifications
The research shows some potentially serious long-term consequences after ACL surgery. These include:
- Higher overall degeneration rate of knee cartilage
- Nearly a 3.6x increase in developing osteoarthritis (OA), compared to an uninjured knee. However, not getting an ACL repair leads to a 4.98x increase in developing OA.
- OA risk is even higher when the original ACL rupture also involves damage to the knee cartilage. Research shows anywhere from an 18% to 48% increase in osteoarthritis (OA) risk with this combined injury compared to only an ACL rupture.
Those are in addition to the ACL re-injury rates that I listed back in section I.
Obviously Liverpool already knew Nabil Fekir had an ACL rupture, two additional injuries and procedures, and understood those risks. However, when they saw the MRI and the overt evidence of increased degeneration of knee cartilage, it set off alarm bells and eventually led to the failed re-negotiation.
In the midst of all this, you have a player in Nabil Fekir who was really looking forward to a move to Liverpool and now has to deal with disappointment. However, not all hope is lost.
V. The Future of Nabil Fekir
Obviously his injury history and increased rate of right knee cartilage degeneration isn’t ideal but it’s not a death knell. Rather, it’s a sign that he has to be extra proactive and disciplined in taking care of his right knee and overall physical and mental fitness.
His keys for preventing knee pain and symptoms will be:
- Muscular strength and endurance. Muscles are the body’s shock absorbers so the stronger and more endurance they have, the less force goes into the knee joint.
- Neuromuscular control which is akin to the “software” that controls the physical “hardware”. It consists of the proprioceptive and vestibular systems which are unconscious feedback systems that inform the brain of where the body is in space (joint positioning for example) and help activate the appropriate muscles. The more they’re trained and finely tuned, the more stable and safe the knee joint becomes.
Nabil Fekir has explicitly mentioned the level of diligence he puts into reinforcing the right knee.
However, building muscle strength and training the proprioceptive and vestibular systems around the knee after an ACL rupture can be an uphill battle. Research shows that an ACL rupture causes long-term weakness in key knee muscles, specifically the quads, and decreased proprioception around the knee joint due to something called “arthrogenic muscle inhibiton” in which pain and swelling in the knee joint actually impair muscle activation.
I wouldn’t be surprised if Nabil Fekir does miss games here and there (barring overt injury) due to increased inflammation and irritation in that knee joint. There’s the possibility he eventually looks into cartilage restoration procedures like matrix assisted autologous chrondocyte implantation or microfracture.
Regardless, that right knee will have to be managed methodically and astutely.
If he’s able to do so and able to avoid additional serious injuries to his right knee while keeping his mindset positive and resilient and continuing to work extremely diligently on his right knee muscle strength/endurance, sensory systems, and overall fitness, it’s definitely possible that he has an extended career in Europe and at some point does make that fated trip to Anfield to never walk alone.
Or to get his revenge.
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Disclaimer: This is not medical advice and shouldn’t be taken as such. If you’re having medical issues, reach out to a medical professional.