Raising Questions About Article On Navicular Stress Fractures

I am writing in regard to the feature article “Diagnosing and Treating Navicular Stress Fractures” (see page 52 in the November 2010 issue or see https://www.podiatrytoday.com/what-you-should-know-about-navicular-stres… ).

   I have also read the article that was published by Joseph S. Torg, MD, and colleagues in the May 2010 issue of the American Journal of Sports Medicine and this article was referenced in the Podiatry Today feature article.1 I encourage your readership to read not only that article in the American Journal of Sports Medicine but the subsequent “Letter to the Editor” the American Journal of Sports Medicine published by Amol Saxena, DPM, FACFAS, and myself.2

   It is my opinion that the authors have misinterpreted the findings from the papers I co-authored with Dr. Saxena and Dr. Hannaford. We presented the largest series of navicular stress fractures in North America. In the Journal of Foot and Ankle Surgery article, we presented a method for classifying navicular stress fractures.3 Type I is in the dorsal cortex, type II enters in the body and type III involves two cortices. We concluded that type I fractures will typically resolve with six to eight weeks of non-weightbearing immobilization as described by Khan in 1992 in the American Journal of Sports Medicine.4

   We also advocated a course of conservative therapy for Type II and Type III fractures. However, we found that type III fractures typically do not heal with conservative treatment while type II fractures can go either way. This CT classification system has been acknowledged by the orthopedic literature as well.5

   In our second paper, published in 2006, we found that surgical treatment of type II and III fractures led to a similar return to activity as non-surgically treated type 1 fractures.6 Unfortunately, the authors of the November feature article in Podiatry Today misinterpreted this as “no significant difference between surgical and conservative management.” This actually means in order for more severe navicular injuries to heal on time, they often will require surgery. In regard to other studies, type II and III injuries may have not been followed long enough to see if the patients really returned to sport, developed degenerative joint disease (DJD) or re-fractured. Refracture is often underreported as many patients will go elsewhere for treatment.

   Both of our papers also involved athletes, many of whom compete on a high level. We classify success as a complete return to activity in the desired sport of the patient. More than half of our surgical patients already had six weeks or more of non-weightbearing prior to undergoing surgery. The authors could have asked us that as they actually had us e-mail our data for their “meta-analysis” (which it wasn’t as there was a mixed bag of injuries and treatment).1 It is also important in certain patient populations to present surgical management of a Type III fracture as a first-line treatment. This is especially the case for professional athletes for whom the difference between three and six months of healing along with refracture is a big deal.

   I would advise anyone to question 100 percent success rates with any treatment (we had a 94 percent success rate with our surgical patients) and recommend an investigation into what basis the success is reported.6 The authors stated in their article that “Case series or reports from Ostlie, Alfred, Murray, Towne, Goergen, Ariyoshi, Miller and Ting all report a 100 percent success rate when utilizing at least six weeks of non-weightbearing management.” The majority of these articles are case reports involving only one or two patients. Clearly, there is not sufficient data from any of these to make any conclusions regarding treatment.7-14

   In the 1970 article by Towne and colleagues, they reported on two cases and one underwent surgery.7 Ostlie and Simons report on one patient and the CT scan clearly shows a Type I fracture, for which conservative treatment should almost always work.8 Alfred and co-workers report on only one patient.9 Murray and colleagues report on two patients.10 Goergen and co-workers reported on two cases.11 In one of the cases, the patient was casted for five months. In the second case, there was no discussion of treatment or return to activity. Ariyoshi and colleagues reported on only one case and the point of that article was the use of MRI for monitoring the fracture.12 Miller and Poulos report on one case.13

   Another point is the authors’ statement that “MRI is better suited for navicular stress fractures.” I am not sure what the basis is for this statement. I have consistently found CT scan to be a much better choice for evaluation of a navicular stress fracture.

   We feel that astute clinicians, after reading our papers and the subsequent conclusions, will recognize that the blanket statement about six weeks of non-weightbearing being the “standard of care” for both partial and complete navicular stress fractures is wrong. That would be analogous to saying the initial treatment for all fibular fractures is non-surgical. One must compare “apples to apples.”

— Brian Fullem, DPM, FACFAS
Tampa, Fla.

References
1. Torg JS, Moyer J, Gaughan JP, Boden BP. Management of tarsal navicular stress fractures: Conservative versus surgical treatment: A meta-analysis. Am J Sports Med. 2010;38(5):1048-53.
2. Saxena A, Fullem B. Comment on Torg et al, “Management of tarsal navicular stress fractures: conservative versus surgical management.” Am J Sports Med. 2010;38(10):NP3-5; author reply NP5.
3. Saxena A, Fullem B, Hannaford D. Results of treatment of 22 navicular stress fractures and a new proposed radiographic classification system. J Foot Ankle Surg. 2000;39(2):96-103.
4. Khan KM, Fuller PJ, Brukner PD, Kearney C, Burry HC. Outcome of conservative and surgical management of navicular stress fractures in athletes. Eighty-six cases proven with computerized tomography. Am J Sports Med. 1992:20(6):657-66.
5. Mann J, Pedowitz D. Evaluation and treatment of navicular stress fractures, including nonunions, revision surgery and persistent pain after treatment. Foot Ankle Clin. 2009; 14(2):187-204.
6. Saxena A, Fullem B. Navicular stress fractures: A prospective study on athletes. Foot Ankle Int. 2006;27(11):917-21.
7. Towne LC, Blazina ME, Cozen LN. Fatigue fracture of the tarsal navicular. J Bone Joint Surg Am. 1970;52(2):376-8.
8. Ostlie DK, Simons SM. Tarsal navicular stress fracture in a young athlete: Case report with clinical, radiologic, and pathophysiologic correlations. J Am Board Fam Pract. 2001;14(5):381-5.
9. Alfred RH, Belhobek G, Bergfeld JA. Stress fractures of the tarsal navicular. A case report. Am J Sports Med. 1992;20(6):766-8.
10. Murray SR, Reeder M, Ward T, Udermann BE. Navicular stress fractures in identical twin runners: High-risk fractures require structured treatment. Phys Sportsmed. 2005;33(1):28-33.
11. Goergen TG, Venn-Watson EA, Rossman DJ, Resnick D, Gerber KH. Tarsal navicular stress fractures in runners. AJR Am J Roentgenol. 1981;136(1):201-3.
12. Ariyoshi M, Nagata K, Kubo M, Sonoda K, Yamada Y, Akashi H, et al. MRI monitoring of tarsal navicular stress fracture healing--a case report. Kurume Med J. 1998;45(2):223-5.
13. Miller JW, Poulos PC. Fatigue stress fracture of the tarsal navicular. A case report. J Am Podiatr Med Assoc. 1985;75(8):437-9.
14. Ting A, King W, Yocum L, Antonelli D, Moynes D, Kerlan R, et al. Stress fractures of the tarsal navicular in long-distance runners. Clin Sports Med. 1988;7(1):89-101.