A medical examination of Zion Williamson’s knee surgery and what it means for his career

In 2017, a 17-year old high school phenom captivated the basketball world. With astonishing and seemingly inhuman viral dunks, Zion Williamson had teased basketball devotees with only a taste of what was to come.

Williamson’s viral high school dunks left the basketball world waiting for more.

A five-star recruit, and №2 in ESPN’s Class of 2018 rankings, Williamson committed to Duke for his inevitable one-and-done freshman season [1]. Despite the Blue Devils’ unprecedented roster talent, Williamson delivered a historic collegiate season that established him the unanimous first pick in the NBA’s annual Draft. The New Orleans Pelicans, fortunate recipients of the basketball lottery, selected Williamson №1 overall in the 2019 NBA Draft as their franchise cornerstone.

Williamson (right) with NBA Commissioner Adam Silver (left) after being drafted first overall in the 2019 NBA Draft.

Basketball aficionados have awaited Williamson’s NBA debut for quite some time. Even with tempered expectations, fans must be impressed by Williamson’s production in four preseason games: in under 28 minutes, averages of 23.3 points, 6.5 rebounds, 2.3 assists, 1.5 steals, and 71.4 FG% (!) [2]. Those performances included an utter domination of the Chicago Bulls, in which he scored 29 points on 12/13 shooting — Williamson’s ridiculous shot chart depicts his unstoppable paint presence.

Williamson’s Shot Chart against the Chicago Bulls (Oct. 9, 2019) in a preseason game [NBA.com/Stats].

A successful preseason foresaw Williamson as a virtual Rookie of the Year lock, leading the Pelicans to a competitive record and potential background chatter for an All-Star nomination. That was until a precautionary MRI for knee tightness in mid-October revealed the worst: a torn meniscus would require surgery and sideline Williamson for 6–8 weeks [3]. A December return outlooks a best case scenario where Williamson misses roughly 25 games. In the Pelicans’ official statement, surgery was classified as debridement of the lateral meniscus of the right knee— key details into Williamson’s long-term outlook [3].

The official statement of Williamson’s surgery details released by the New Orleans Pelicans (twitter.com/PelicansNBA) on Oct. 21, 2019.

While meniscus injuries assert fear at diagnosis, they are rather familiar in the NBA landscape. From 20 seasons of NBA injury reports, knee issues accounted for nearly 10% of total injuries [4]. Of the nearly 1,700 sustained knee injuries, around 8% were meniscus tears without injury to other ligaments — Williamson’s injury is classified as such [4]. As expected, the result of a meniscus tear varies by player and is specific to damage and treatment, as well as physique, rehab, and longstanding care.

The menisci of the knee are comprised of fibrocartilage that serve to withstand heavy loads of stress while maintaining elasticity [5]. Menisci absorb lateral shock and keep the knee in place during motion. The lateral mensicus is nearly circular and plays a significant role in weight bearing and joint motion [5].

The anatomy of the knee includes the ACL (anterior cruciate ligament), MCL ( medial collateral ligament), medial meniscus, and lateral meniscus. The lateral meniscus is a fibrocartilaginous band that spans the side of the knee joint interior. It is nearly O-shaped and covers a larger portion of the articular surface than the medial meniscus.

The lateral meniscus is susceptible to injury from fundamental basketball motions: jumps, cuts, sprints, and sudden stops. An unorthodox twist of the knee during bending can result in a tear. With rest, slight tears located in blood rich areas can heal quickly. However, more common are significant tears requiring surgery. Meniscal surgeries are categorized as repair, debridement, or full removal [6]. The course of action depends on injury location and tear classification: flap, longitudinal, radial, and more. If the meniscus can be salvaged, repair is the ideal route in order to preserve the knee’s natural load bearing structure. If not, in debridement— partial removal of the meniscus — and full removal, the shock absorbance provided by the meniscus is removed. As a result, force is transferred directly to the cartilage surfaces on the bone. This route is usually undesirable— retired NBA All-Star Dwyane Wade regrets the early removal of his left knee meniscus that led to ongoing knee problems throughout his career [7].

According to MD Brian Sutterer, partial removal — like Williamson’s operation— alters the biomechanical load bearing of the knee, which may result in early signs of arthritis [8]. For a lateral meniscus tear, concern centers on alignment of the knees and corresponding force distribution. Williamson’s odd gait — his manner of walking — has been previously scrutinized. Side-to-side movement of his upper trunk resembles a trendelenburg gait, a manner of walking associated with hip pathology [8]. In addition, Williamson also displays signs of dynamic knee valgus, or inward knee bend during normal walking that raises concern for the stability of his lower limbs. His history of knee injuries is alarming in the past year alone. A Grade 1 right knee sprain sidelined him three weeks at Duke, and a bruised left knee saw him miss the entire NBA summer league after only 9 minutes.

Williamson’s unusual side-to-side gait raises concerns for further inward knee collapse following his lateral meniscal debridement (twitter.com/NickFriedell).

An alarming concern with Williamson’s lateral mensical tear is further misalignment, which can originate in outer bowing or inner collapsing of the knees [9]. Extremes in either direction result in disproportionately loaded medial or lateral knee compartments, introducing risks for ACL, MCL, or further meniscal injuries. An important factor for Williamson’s long-term sustainability is proper knee alignment through effective rehab and strengthening exercises —squats, bridges, quad sets, etc. Muscle memory adjustments to specific basketball actions will also help stress bearing in his knees, detailed later.

Knee alignment is categorized as normal, varus, or valgus. Williamson already displays signs of valgus, or inward collapsing of the knees. Without proper rehab and strengthening exercises, further misalignment can result following his lateral meniscus tear, placing him at higher risk for future injury.

Despite Williamson’s meniscal tear at 19-years old, an injury-plagued career is premature. Players have successfully recovered from meniscal injuries without further recurrence. The highly explosive Russell Westbrook suffered a torn right meniscus in 2013 [10]. Since, he’s retained the same remarkable athleticism without significant lingering issues. Westbrook, of course, does not flaunt nearly the same physique as Williamson — his unique anatomy requires a closer look.

There has never been an athlete in the sport of basketball quite like Williamson. While comparisons to NBA greats like King James or Sir Charles Barkley set quite the standard, even their physical profiles don’t compare. At 6'6" and 284 lbs, Williamson has a reported 45 inch vertical leap [11,12]. This incredible ability is ranked first among NBA players weighing 240 lbs or more [12]. For reference, former Lob City member Blake Griffin (248 lbs) recorded a 35.5 inch vertical [12]. At his weight, Williamson is also the second heaviest player in the NBA behind only 7'4" Boban Marjanovic [14]. At these extremes, Williamson’s motions provide force outputs atypical of any NBA player today. There is no doubt when healthy that Williamson is a generational physical specimen in line for a remarkable career.

But these exceptional gifts also sprout alarming red flags for his longevity. Williamson’s weight is a legitimate concern. According to Orthopedics Today, a body mass index (BMI) of 25 or more is considered overweight [15]. They conclude that these patients are at least three times likelier to suffer a meniscal tear than the average person. Other studies conclude that a high body mass increases the load on the knees, resulting in decreased cartilage integrity [6]. Williamson records a BMI of 32.8. Unfortunately, the knees do not differentiate between muscle mass and fat [12]. Williamson’s extreme body transformation is well documented. In four years, he grew 4" while adding over 100 lbs [7]. Despite this enormous gain in muscle, important tissues — specifically lower limb ligaments and tendons — don’t necessarily grow at equivalent rates [8]. There is concern that the surrounding soft tissues of his joints have not matured to support his stature.

Therefore, Williamson finds himself in a unique predicament. At under 10% body fat, he does not appear to be carrying unnecessary weight [13]. In fact, Pelicans General Manager David Griffin asserts that Williamson is in “elite shape” [13]. NBA trainer Paul Fabritz also notes that Williamson is incredibly lean [16]. He believes that Williamson’s body maintains the natural weight for a reason. In any scenario to reduce this weight, a required caloric deficit would decrease muscle mass [16]. Other consequences would follow suit, including weakened muscles, tendons, and joints. This offset of lower overall ground reaction force on weakened joints invites plenty of other complications. According to NBA insider Shams Charania, the Pelicans are adopting a similar approach. Williamson’s rehabilitation could mean less weight-lifting and more strategic planning, but the Pelicans do not expect to manage his weight [17].

So, what can Williamson do to improve his career longevity?

While controversial, a minor reduction in playing weight would likely provide a beneficial start. To attain a BMI of 30, Williamson would need to drop to 260 lbs. This 8% weight reduction provides an effective means to reduce load-bearing on the ligaments and tendons in his knees, while also averting drastic shifts in Williamson’s natural muscle make up. For reference, Lebron James, who has a BMI of 27.5, has avoided major knee injuries throughout his career.

Williamson should also make adjustments to his jump patterns. Although his explosive leaping ability is instrumental to his dynamic play, his relentless approach leaves him prone to a matter of chance. Notably, a shift to two-footed jumps when feasible — transition baskets, open dunks, or rebound attempts — presents a safer alternative to single-footed leaps. By reducing the load stress amongst both limbs, two-footed jumps minimize the shearing in each knee. Similarly, landing with two feet instead of one during dunks, layups, or rebounds are a more reliable cushioning mechanism for Williamson’s enormous downward force. These mechanical adjustments will require repetition to his muscle memory, but will ultimately serve him well in the long-term.

Williamson’s game revolves around relentless attacking of the basket through hard cuts, explosive jumps, and quick pivots. As he improves, his ability to impact the game in more ways than pure elevation will serve his career longevity well.

Williamson can also evolve his style of play to reduce his need to elevate as much as possible. Right away, layups in the place of open dunks is an effortless adjustment for Williamson to preserve his body. Regardless of injury prevention, his development of a reliable jump shot is a necessary step towards his growth as a complete player. Similarly, Williamson’s ability to develop post moves will be instrumental to diversify his offense, ultimately reducing his need to drive hard and finish over defenders to score. His capability to facilitate and create for teammates will provide the same value. Fortunately, these adjustments will come naturally through Williamson’s experience and growth in the NBA. In due time, the better Williamson develops as a player, the further he can drive his career longevity.

Zion Williamson is a truly unique player whose rare physique adjoins the boundary between basketball hysteria and unavoidable concern. Hopefully, with successful rehab and careful long-term consideration, Williamson prospers for a healthy playing career in which he continues to captivate the basketball world.

References

1. “ESPN Basketball Recruiting — Player Rankings.” ESPN, ESPN Internet Ventures, 2018, www.espn.com/college-sports/basketball/recruiting/playerrankings/_/class/2018.
2. “Zion Williamson NBA Stats — Season & Career Preseason Statistics.” Home — Sports News, Scores, Schedules, and Videos, www.foxsports.com/nba/zion-williamson-player-stats?seasonType=3.
3. Blackburn. “Zion Williamson Injury Update.” New Orleans Pelicans, NBA.com/Pelicans, 21 Oct. 2019, www.nba.com/pelicans/news/zion-williamson-injury-update-10-21-19.
4. Pittman, Genevra. “Most NBA Players Recover from Meniscus Tears.” Reuters, Thomson Reuters, 16 Dec. 2011, www.reuters.com/article/us-nba-players-meniscus/most-nba-players-recover-from-meniscus-tears-idUSTRE7BF23P20111216.
5. Stotts, Jeff. “Understanding Zion Williamson’s Lateral Meniscus Tear.” In Street Clothes, 21 Oct. 2019, instreetclothes.com/2019/10/21/understanding-zion-williamsons-lateral-meniscus-tear/.
6. Zedde, Pietro, et al. “Meniscal Injuries in Basketball Players.” Institute of Orthopaedics and Traumatology.
7. Windhorst, Brian. “Dwyane Wade Regrets 2002 Surgery.” ESPN, ESPN Internet Ventures, 2 Oct. 2013, www.espn.com/nba/truehoop/miamiheat/story/_/id/9760169/dwyane-wade-miami-heat-regrets-having-meniscus-removed-college.
8. “ Zion Williamson Injury Risk.” YouTube, YouTube, www.youtube.com/watch?v=HGRnMIRCtDU.
9. “Zion Williamson Tore His Meniscus.” YouTube, YouTube, www.youtube.com/watch?v=HC3i2YNJHic.
10. Winfield, Kristian. “A History of Russell Westbrook’s Many Knee Surgeries.” SBNation.com, SBNation.com, 12 Sept. 2018, www.sbnation.com/2018/9/12/17851948/russell-westbrook-knee-injury-surgery-history-thunder.
11. “Official NBA Bio of Zion Williamson.” NBA.com, www.nba.com/players/zion/williamson/1629627.
12. Lynch, Mike. “The Feats of Zion.” The Ringer, The Ringer, 18 Jan. 2019, www.theringer.com/college-basketball/2019/1/18/18187476/zion-williamson-duke-numbers-ncaa-nba-draft.
13. Lopez, Andrew. “Pelicans Say Zion Williamson’s Weight Not Cause of Knee Injury.” ESPN, ESPN Internet Ventures, 22 Oct. 2019, www.espn.com/nba/story/_/id/27902754/pelicans-say-zion-williamson-weight-not-cause-knee-injury.
14. “Official NBA Bio of Boban Marjanovic.” NBA.com, www.nba.com/players/boban/marjanovic/1626246.
15. May 5, 2005. “Overweight Patients Face Higher Meniscal Tear Risk.” Healio, www.healio.com/orthopedics/knee/news/online/%7B9d61da87-2d5b-461b-850e-8ae95e5a6463%7D/overweight-patients-face-higher-meniscal-tear-risk.
16. “Zion Williamson Training/Workout/Diet Thoughts.” YouTube, YouTube, www.youtube.com/watch?v=XKH1MZhKytM&t=3s.
17. Charania, Shams. “Charania: Origin of Zion Williamson Knee Injury Remains…” The Athletic, The Athletic, 22 Oct. 2019, theathletic.com/1313234/2019/10/22/charania-origin-of-zion-williamson-knee-injury-remains-unclear-pelicans-not-concerned-about-his-frame/.