Keys To Diagnosing And Treating Calcaneal Apophysitis

Given that calcaneal apophysitis is a common cause of heel pain in children, this author reviews the literature and offers insights on the etiology of the condition, the diagnostic workup and pertinent treatment pearls.

   Calcaneal apophysitis is a traction apophysitis of the insertion of the Achilles tendon into the calcaneus.1 In 1912, Sever noted this condition is not unusual in growing children but one would never encounter it after the child reaches puberty. Sever considered the condition to be a muscle strain and suggested rest and protection to resolve the condition. He did not say that calcaneal apophysitis was an osteochondrosis although other authors have classified it as such.2-4

   Although this condition was once considered a true osteochondritis, it is now generally agreed that this condition is a mechanical overuse syndrome with a self-limited, benign prognosis.5 Calcaneal apophysitis is an overuse syndrome. It is analogous to tibial tubercle apophysitis, a condition also known as Osgood-Schlatter disease.6 Other common traction injuries that may be similar include injuries to the medial epicondyle, iliac apophysis and the inferior pole of the patella and fifth metatarsal base.7

   One study focused on 3,805 injuries that occurred over two seasons of youth football (soccer) leagues in Britain. Researchers found that growth-related injuries, including Sever’s disease and Osgood-Schlatter’s disease, accounted for 5 percent of total injuries, peaking in the under-11 age group for Sever’s disease.8

   Calcaneal apophysitis is most common in boys ages 10 to 12 who are active in sports.9 However, with the rise in sports participation by girls, calcaneal apophysitis is believed to occur more frequently in girls ages 8 to 10.7 In one study of 85 patients with calcaneal apophysitis, 75 percent of patients were male.10

   Specific sports that have been frequently associated with this condition include soccer, gymnastics, football, baseball, ice hockey, tennis, figure skating, ballet, tae kwon do and various running sports.11

   A 2008 retrospective study by Lau and colleagues focused on 506 pediatric patients diagnosed with sports-related overuse injuries over a study period of five years and seven months.12 Researchers diagnosed apophysitis in 32.4 percent (164 patients) at the mean age of 9.9 years. This was the youngest mean age of diagnosis of any of the conditions the researchers reported. In this study, 61 percent of those patients with apophysitis had bilateral symptoms.

   In the critical review of the literature, Scharfbillig and co-workers state that “although the literature contains a fairly large number of studies that have reported the incidence of Sever’s disease, the lack of consistency in reporting, use of multiple raters, and retrospective analysis of notes reduce the confidence with which the findings can be accepted.”13

A Closer Look At Etiological Triggers

   The most common cause of calcaneal apophysitis is believed to be repetitive microtrauma or overuse, which leads to injury and symptomatology at the apophysis.10 Apophyses have a higher composition of fibrocartilage than epiphyses. Epiphyses are composed of more hyaline cartilage and are subjected to more axial load.

   Volpon and colleagues conducted a study with 69 patients with apophysitis and 392 normal children with no symptoms.14 They reported that the most significant differences in the calcaneal X-rays of the two groups was a greater degree of fragmentation of the apophysis. The authors concluded that the greater degree of fragmentation suggests a mechanical etiology for apophysitis.

   Strong shear stresses affect the apophysis as a result of its vertical orientation. Researchers believe the pull of the Achilles tendon on the unossified apophysis contributes to these strong shear stresses.7 A 2005 ultrasonographic study, which supports the finding of fragmentation of the apophysitis, examined 21 symptomatic heels in 14 children with apophysitis. The study found that all these heels showed fragmentation of the secondary nucleus on both conventional radiographs and sonography.15

   Aggravating factors may include an imbalance as prepubertal long bone growth often exceeds muscle and tendon growth, limited dorsiflexion of the ankle and other biomechanical abnormalities.16,17

What To Look For In The Clinical Presentation

   The chief complaint is usually pain in one or both heels when running and walking. Some patients will adopt a toe walking gait to avoid aggravating the symptoms.7 Typical symptoms include local tenderness in otherwise healthy children without antecedent trauma. These patients are usually deemed to be in a growth spurt. Eighty percent of patients in one study reported their pain was worse after a specific athletic activity. The sport most likely to be associated with calcaneal apophysitis was soccer (29 percent), followed by basketball, gymnastics and running.10

   Lau and co-workers reported that 76.2 percent of patients who went on to a diagnosis of Sever’s disease presented with heel pain and 83 percent had localized tenderness.12 Physical examination of the patients typically reveals tenderness upon medial and lateral heel compression (the squeeze test). Patients usually experience no erythema, edema, dermatologic abnormalities or other local pathology.

   In their critical review of the literature, Scharfbillig and colleagues state that “although pain and limping are frequently mentioned as symptomatic traits, there have been no attempts to quantify the pain or its effect on the individual.”13 They do acknowledge that although there are many other possible diagnoses for heel pain in the child and adolescent, “there are none that specifically mimic the positive squeeze test of Sever’s disease without a wider spectrum of symptoms.” This led them to conclude that “the diagnosis of Sever’s disease can be made with relative clarity.”

   Patients with calacaneal apophysitis commonly have equinus of the ankle.10 Other biomechanical abnormalities present in patients with calcaneal apophysitis include pes planovalgus, midtarsal pronation, pes cavus and hallux abducto valgus.10

   Scharfbillig and co-workers state that some of the authors who have linked biomechanical etiologies and pathomechanical foot types to this condition have failed to provide evidence of that assumption.13 They further criticize that published “theories that shock attenuation is decreased and load increased on the Achilles tendon because of biomechanical abnormalities, causing increased tension at the apophysis” are only anecdotal and that studies offer “no supporting evidence.”

Essential Insights On Diagnostic Imaging

   A recent study has called into question the need for a diagnostic X-ray in suspected cases of calcaneal apophysitis.9 In this study, 61 consecutive patients with a diagnosis of calcaneal apophysitis had 71 sets of foot radiographs taken to determine whether they had an impact on diagnosis and management. Researchers found pathology leading to an altered diagnosis in only one of the 71 radiographs in a patient with a simple bone cyst of the calcaneus.

   While X-ray findings with apophysitis have historically included reports of resporption, fragmentation and increased sclerosis, these changes frequently occur in asymptomatic heels and may be suggestive but not diagnostic of this condition.9

   One study supporting these X-ray findings looked at X-rays of 35 children with apophysitis and 52 children without apophysitis.18 Liberson and colleagues found increased density of the apophysis on all radiographs of the heels and fragmentation in all 35 painful heels but in only 14 of 52 asymptomatic heels. They further define these fragmentation lines as the “result of stresses due to activity and a process of repair and of bone remodeling, and thus should be termed remodeling lines. The location, direction and histologic patterns of the remodeling lines are consistent with the suggested biomechanical theory.”18

   They go on to state that prevalence of the condition in boys over girls, prevalence in children active in sport, in overweight children and in the dominant foot are all consistent with their theory of biomechanical origin of these fragmentation lines.1,6,18

   Obtaining X-rays in children presenting with heel pain may be useful to rule out other causes such as fracture, neoplasm, tarsal coalition or osteomyelitis. However, in the absence of any history or physical findings suggesting these conditions, the aforementioned recent studies conclude that based upon the low percentage of radiographs yielding an alternate diagnosis when apophysitis is the suspected condition, taking X-rays on a routine basis may not be warranted.

   For patients in whom pain persists despite adequate treatment, increases at rest, awakens the child from sleep or is associated with swelling and other physical changes, a radiograph and other diagnostic tests may be indicated.

   In a 2004 study by Ogden and colleagues, researchers evaluated MRI for 14 patients with a presumptive diagnosis of apophysitis and continued pain after conservative treatment.15 They found evidence of bone bruising within the trabecular bone of the metaphyseal region adjacent to the apophysis. Interestingly, the authors conclude that what is thought to be calcaneal apophysitis may be a metaphyseal stress fracture, similar to the toddler’s calcaneal fracture, with minimal or no involvement of the apophyseal ossification center.

Pertinent Tips On Treatment

   Apophysitis is a self-limiting disease so treatment should focus on reducing pain that is interfering with the child’s activities.

   Treatment consists of a combination of activity modification, icing and stretching of the gastrocnemius-soleus complex. Additional treatments include heel lifts of 0.25 to 0.5 inches thickness (with or without cushioning) to decrease the pull of the Achilles tendon. One may also utilize analgesic medications if necessary. One author recommends a prescription for a 5/8-inch compressible, sponge-filled leather orthotic in a wedge shape for under the heel.5 Most patients return to pain-free activity within three to six weeks.6

   When it comes to children with mild to moderate cases, you may allow them to continue with sports while they are on a treatment regimen that includes heel lifts or cushions, icing before and after activity, anti-inflammatory or pain medication, and a stretching program. If there is persistent pain after a few weeks with this regimen, activity limitation is recommended and one may add a plantarflexory night splint to the regimen.7

   For patients with recalcitrant cases, immobilization with a short-leg cast in a plantarflexed position is recommended. A walker boot for up to one month is an alternative but it may not be as effective as the off-weightbearing cast in the plantarflexed position.4

   One may use custom foot orthoses in those children with biomechanical comorbidities to neutralize those influences during an acute episode or to maintain optimal foot alignment for future development.10 Soft tissue supplementation with shock absorbing materials is recommended. To achieve this, the physician may use a laminated device of more flexible materials or choose a top layer, soft tissue supplement on a more motion-controlling shell or module.

   One can also utilize deep heel seats to accentuate the natural effect of the anatomical fat pad of the heel. Patients should wear these devices as much as possible and should limit the amount of time they are barefoot, even at home. Good supportive shoes with a firm heel counter and shock-absorbent soles are recommended and limiting running on hard surfaces may be helpful.6

   Address sagittal plane muscle imbalances at the ankle by prescribing supervised therapeutic exercises, including gastrocnemius-soleus stretching exercises. The exercises should also include dorsiflexion strengthening. Preferably, patients should do this under the supervision of a physical therapist or at least with careful guidance from you on correct technique for a variety of recommended stretches and exercises for these muscle groups.

   In Lau’s study, apophysitis patients underwent treatment with stretching of the Achilles tendon with one-third of patients advised to get a heel cup.12 Seventy-nine percent (130 patients) experienced resolved symptoms within three months. The remaining 21 percent (34 patients) remained symptomatic after a year. It is unusual to have reports of this many patients with symptoms persisting for this long.

   Although the term apophysitis suggests an inflammatory process, the most likely etiology appears to be the mechanical overuse that occurs during periods of rapid growth. Therefore, corticosteroid injections are rarely indicated. Use oral anti-inflammatory medications only when symptoms warrant.

In Conclusion

   Educating parents and coaches about the clinical presentation of apophysitis may be beneficial in enhancing protective and proactive measures in at-risk children, and instituting appropriate treatment in a timely manner.

   Remember that this overuse syndrome may be preventable and it responds well to physical therapy, improved foot biomechanics and soft tissue supplementation. Children who are at risk for this condition have biomechanical foot imbalances and are engaged in high-impact activities during rapid growth periods.

   In addition, the ever increasing numbers of children who participate in organized sports activities, as well as increasing concerns about obesity in children, make the occurrence of microtraumatic and overuse syndromes of the foot more prevalent.

Dr. Volpe is a Professor in the Departments of Pediatrics and Orthopedics at the New York College of Podiatric Medicine. He has a pediatric foot and ankle specialty private practice in New York City and Farmingdale, N.Y.

For further reading, see “Key Insights On Diagnosing Heel Pain In Kids” in the March 2004 issue of Podiatry Today or “Conquering Posterior Heel Pain In Athletes” in the November 2006 issue.
To access the archives or get reprint information, visit www.podiatrytoday.com.

References:

1. Sever JW. Apophysitis of the os calcis. New York Med 1912; 95:1025-29. 2. Katoh Y, Chao EYS, Murray BF, Laughman RK. Objective technique for evaluating painful heel syndrome and its treatment. Foot Ankle 1983; 3(4):227-37. 3. Pappas AM. The osteochondroses. Pediatr Clin North Am 1967; 14(3):549-69. 4. Kvist M, Kujula U, Heinonen O, Kolu T. Osgood Schlatter and Sever’s disease in young athletes. Duodecim 1984; 100(3):142-50. 5. Weiner D, Morscher M, Dicintio M. Calcaneal apophysitis: simple diagnosis, simpler treatment. J Fam Pract May 2007 56(5):352-5. 6. Micheli LJ, Ireland ML. Prevention and management of calcaneal apophysitis in children: an overuse syndrome. J Ped Ortho 1987; 7(1):34-38. 7. Hendrix CL. Calcaneal apophysitis (Sever disease). Clin Podiatr Med Surg 2005; 22(1):55-62. 8. Price RJ, Hawkins RD, Hulse MA, Hodson A. The Football Association medical research programme: an audit of injuries in academy youth football. Br J Spts Med 2004; 38(4):466-471. 9. Kose O. Do we really need radiographic assessment for the diagnosis of non-specific heel pain (calcaneal apophysitis) in children. Skeletal Radiol August 2009 (epub ahead of print). 10. Szames SE, Forman WM, Oster J, et al. Sever’s Disease and its relationship to equinus: a statistical analysis. Clin Podiatr Med Surg 1990; 7(2):377-84. 11. Madden CC, Mellion MB. Sever’s disease and other causes of heel pain in adolescents. Am Fam Phys 1996; 54(6):1995-2000. 12. Lau LL, Mahadev A, Hui JHP. Common lower limb sports-related injuries in young athletes. Ann Acad Med 2008; 37(4):315-319. 13. Scharfbillig RW, Jones S, Scutter S. Sever’s disease: what does the literature really tell us? J Am Pod Med Assn 2008; 98(3):212-223 14. Volpon JB, de Carvalho Filho G. Calcaneal apophysitis: a quantitative evaluation of the secondary ossification center. Arch Orthop Trauma Surg; 122(6):338-41. 15. Ogden JA, Ganey TM, Hill JD, Jaakkola J. Sever’s injury: a stress fracture of the immature calcaneal metaphysis. J Pediatr Orthop 2004; 24(5):488-492. 16. Wiley JJ, Profitt A. Fractures of the os calcis in children. Clin Orthop 1984; 188:131-8. 17. Micheli LJ. Pediatric and adolescent sports injuries: recent trends. Exerc Sport Sci Rev 1986; 14:359-74. 18. Liberson A, Lieberson S, Mendes DG, Sharjrawi I, Ben Haim Y, Boss JH. Remodeling of the calcaneal apophysis in the growing child. J Pediatr Orthop B 1995; 4(1):74-79.