Podiatry Primer: A Med Student on Embiid’s Injury

(Photo by Cooper Neill/Getty Images)

Special to SCH: Former Jazzbot writer Danny Hansen is a fourth-year medical student at the Arizona School of Podiatric Medicine at Midwestern University. As a specialist in the area of medicine specific to Joel Embiid’s injury, he brings his knowledge to bear in this special guest post on the medical realities of Embiid’s injury and whether the Jazz should consider drafting him.

Early Thursday, news appeared that top draft prospect Joel Embiid had a broken foot. GMs and the media were sent scrambling to gather more information. Draft boards across the league and mock drafts across the Internet were in disarray as we waited to discover which of the foot’s 26 bones was actually broken. It was later revealed that the Kansas phenom had a stress fracture of his navicular bone.

A panic then followed. The navicular bone has been known to affect the careers of Yao Ming, Bill Walton, Zydrunas Ilgauskas, and former Jazzman Curtis Borchardt. Embiid’s status has been elevated to “ultimate risk”. However, looking at his condition, how much of a risk is it really to draft Embiid? If he were to fall to the Jazz at #5, should they select him? To better answer these questions, we need to analyze his situation and condition. What is the navicular bone? How long does it take to heal? Will this be a chronic problem for him?

The Navicular and Stress Fractures

The navicular is a comma-shaped bone on the medial¹ side of your midfoot. It serves as the location for various ligament and tendon attachments. It is the keystone of the medial longitudinal arch². The blood supply for the navicular comes from branches off an artery on top of the navicular, which come together with branches off an artery on the bottom of the navicular. This pattern creates an area in the center of the bone where blood supply is poor, also known as a watershed area. Watershed areas are more prone to fracture and take longer to heal. 

Navicular stress fractures usually run in a vertical pattern, and involve the body of the navicular, or the center area of the bone.  These kinds of stress fractures in the navicular account for 15% of all stress fractures in the foot. There are 3 kinds of these stress fractures. A Type I fracture means only the upper portion of the bone is fractured and it only descends minimally into the body of the bone. Type II is like a Type I, but it does descend into the body of the bone. Both a Type I and Type II are called incomplete fractures. Finally, a Type III involves the upper portion of the bone, descends through the center of the bone, and fractures on the far side of the bone. It is called a complete fracture. 

A Type I or Type II can be treated by putting the patient in a cast and keeping them off it for 6 weeks and slowly transitioning to weight bearing and physical therapy. A Type III is most often fixed with surgery. However, as is the case with Joel Embiid and other young athletes who will be putting a lot of stress on their feet in the future, surgical repair with a screw across the fracture site is usually done in all three types.  So, Embiid’s choice to have have surgery doesn’t necessarily mean that he has a Type III fracture. It is more likely, given his status as a young professional athlete and the fact it hadn’t been picked up until recently, that surgery is done to ensure it heals properly and quickly. 

Healing Time

Average return to activity for patients treated surgically and non-surgically for a Type I fracture was 3.0 months. For a Type II, healing time was 3.6 months. And for a Type III fracture, return to activity was found to be about 6.8 months. Patients who had surgical correction were found to return to activity quicker than those who were treated conservatively³.  Other things, such as bone grafting and bone stimulation, can be done to aid in fracture repair. 

Reports surfaced after Embiid’s operation on Friday that he had 2 screws placed in his navicular and that his recovery time is 4 to 6 months. Once can speculate that perhaps Embiid had a Type II stress fracture of the navicular. This is definitely a better prognosis than a Type III. His recovery time indicates how soon he can return to activity and isn’t necessarily the time until he will play in the NBA. Any team that selects is going to be extremely patient to ensure the bone has adequate strength before allowing him to return to the court. 

Complications

Because of the unique blood supply in this part of the foot, and possible disruption of that blood supply, there is a chance of the fracture not healing. There is also the risk of the bone undergoing avascular necrosis, death of the bone due to lack of blood supply, as was the case with Curtis Borchardt. Refracturing the navicular is also a possibility. Yao Ming had numerous tiny fractures in the navicular that required multiple screws.

Studies show, however, that non-healing and avascular necrosis is more the exception than the rule. The problem with these studies, though, is that they weren’t conducted on professional athletes over 7 feet tall.  Joel Embiid, currently at 240 pounds, isn’t as heavy as those mentioned before (Yao Ming weighed 311 lbs, Zydrunas Ilgauskas 260), which means less stress on his feet. He is, however, more of a leaper than those other players, which adds its own forces to the foot and the previous fracture site. There are multiple theories as to the causes of navicular stress fractures. Some speculate anatomical variety, such as a high arched foot, or a short 1st metatarsal bone could contribute to increased stress on the navicular. Though these theories aren’t proven, you can bet teams will be assessing the biomechanical function of Embiid’s feet very carefully. 

Is He Worth the Risk at #5?

Embiid has the chance to be a very special player. Experts have said he reminded them of NBA great and two-time Finals MVP Hakeem Olajuwon. In a league void of impactful centers, he could be the best center in the league in a couple of years. There is no doubt he has the talent to be special. There is a good chance his navicular will heal correctly, quickly, and never be a problem again. However, Joel Embiid is a special case. He is an athletic 7 footer, who is light on his feet. He had a foot fracture that was found only recently. We won’t really know the extent of the injury until doctors get in there and assess the quality of the bone. We haven’t even mentioned his back troubles that kept him out for a big chunk of his season at Kansas, which is a serious risk in and of itself. 

If I have the #1 pick, as the Cavs do, there is a 0% chance that I take Embiid. In this draft, with other potential superstars in the waiting, you can’t miss with the first pick. However, with the 5th pick, once the potential superstars are off the board, I do seriously consider it. Do you take the potential superstar with health risks, or do you take somebody like Noah Vonleh, with just some all-star potential but more of a sure thing health-wise? It comes down to what kind of risk taker you are. When your team is down two with five seconds left, do you go for a three-pointer, or do you play it safe with the two to try and force overtime? What kind of risk taker is Dennis Lindsey? We’ll find out on draft night, but somebody is sure to take the risk.

– Danny Hansen, 4^th Year Medical Student, Arizona School of Podiatric Medicine at Midwestern University