Posterior heel pain: the Physiotherapist's Achilles' heel?

The state of the tendon also has an impact on management. Cook and Purdam’s model of the tendinopathy continuum is useful in determining the state of the tendon and predicting the recovery potential (see figure 2)⁽³⁾. Reactive tendinopathy responds well to managing load and minimizing compression forces and is completely reversible. Tendon dysrepair implies an element of change to the structure of the tendon. Although these changes may not be reversible, it is possible to rehabilitate a fully functional, strong tendon with some structural disruption in the remaining tendon. Degenerative tendinopathy is seldom reversible. Assessing where the patient is on this continuum guides the management plan.

Basic principles of Achilles tendon management

o    Unload
o    Manual therapy to release the calf
o    Joint mobilization of the foot and ankle 
o    No stretching or compression
o    Isometrics
o    Gradual loading
o    Correction of biomechanics or contributing factors
o    Return to sports

 

Plantaris

Plantaris weakly plantarflexes the ankle joint and flexes the knee joint in conjunction with the calf muscles. It is a weak antagonist to the tibialis anterior. Evolutional studies suggest that it is a rudimentary muscle that plays a minor role in gait. It is suggested that it is superfluous, but it has a high proportion of muscle spindles, indicating its importance in providing proprioceptive feedback regarding the foot’s position⁽⁴⁾.

The plantaris tendon crosses the Achilles tendon medially and is often the cause of friction as it tightens and rubs against the Achilles tendon when it contracts. Clinically pain at the point where plantaris crosses the tendon is definitive. It is helpful to use soft tissue techniques from the medial Achilles proximally all the way to the plantaris muscle to release any possible tightness. Sometimes this super thin tendon ruptures spontaneously, releasing the friction, and the frictional tendinopathy recovers quickly. In other instances, a surgical release may be necessary and sacrifices the proprioceptive benefit of plantaris (see figure 3). 

Sever’s disease

Sever’s disease is easily diagnosed clinically and presents with a typical history. Also known as calcaneal apophysitis, patients are between eight and twelve years old, generally very active, and play high-impact sports on hard surfaces, especially barefoot. Often these children "do it all" and love being on the sports field, making it difficult to slow them down. However, Sever’s does slow them down because the pain significantly affects their performance. The pain gradually increases and is often most severe during a growth spurt. There is not typically a traumatic event.

Along with the typical history, compression of the calcaneus, where the calcaneal apophysis attaches to the main body, will reproduce the patient’s pain. X-rays are not required except to exclude any more sinister finding or if there happens to be suspicion of a traumatic event. In severe cases, there is sometimes increased sclerotic density of the calcaneal apophysis on X-ray. The calcaneal apophysis is typically fragmented, and this radiological finding should not cause alarm⁽⁶⁾.

Sever’s is a self-limiting condition, and symptoms ease as the growth plates begin to close. Before then, modified activity to unload the area, rest, stretching, heel raises, and better footwear all help.

Posterior ankle impingement syndrome

Posterior ankle impingement syndrome (PAIS) is characterized by posterior heel pain with repeated plantarflexion. Bony anatomical causes include the presence of an os trigonum or Stieda’s process, a bony extension of the posterior talus^(7,8,9).

Os trigonum syndrome

An os trigonum is an unfused accessory bone posterior to the talus. It is generally an asymptomatic coincidental radiological finding and is present in up to 49% of the general population. It has been argued that dancers and sports which plantarflex repeatedly have a higher incidence of os trigonum. However, there is no evidence for this. There is also no evidence that these kinds of activities as a young child result in the non-fusion of the os trigonum.

It is a common radiological finding in ballet dancers, fast bowlers, and soccer players who hyper-plantarflex their ankles. Still, it does not always cause their posterior heel pain⁽¹⁰⁾. Often surgical intervention is recommended when X-rays show an os trigonum present in these young athletes, but the clinical picture may not fit with os trigonum syndrome. This unnecessary surgery could be devastating for future dancing or sports participation.

Ballet dancers repeatedly complete forced plantarflexion when en pointe. There is no doubt that this repeated plantarflexion will compress the os trigonum⁽¹¹⁾. Furthermore, they tightly tie the ribbons and cross the Achilles tendon, causing a possible frictional tendinopathy (see figure 5). Accurate diagnosis is key to good management of these athletes.

Os trigonum syndrome is when the soft tissue structures around the accessory bone become symptomatic⁽¹²⁾. This could be after an acute, severe ankle sprain or due to overuse with repetitive plantarflexion, which compresses the os trigonum and deep posterior structures and causes irritation of the flexor hallucis longus tendon. If the tendon is involved, there will be pain with a combined plantarflexion and big toe extension, as is common in the demi pointe position in ballet.

Conservative treatment (such as rest, immobilization that limits plantarflexion activities, stretching, and manual therapy) is highly effective. Surgical intervention should only be considered as the very last resort.

Conclusion

The human foot is an intricately incredible design. This article only touches on the posterior heel. There are so many nuts and bolts and moving parts that miraculously, usually, all work. Athletes rely on healthy, strong feet to be effectively mobile and to perform well. A thorough understanding of anatomy, biomechanics, and clinical presentations is essential for accurate diagnosis and effective management of posterior heel pain. There is no need for the posterior heel pain to be the Physiotherapist’s weakness. Practitioners have the knowledge to make an enormous difference in these athletes’ lives.

References

1. en.wikipedia.org/wiki/Achilles
2. Foot and Ankle Surgery 28 (2022) 1050–1054
3. Br J Sports Med 2009;43:409–416
4. sportdoctorlondon.com/plantaris-tendon/
5. Am Fam Physician. 2018 Jan 15;97(2):86-93
6. J Orthop Surg Res. 2022 Feb 9;17(1):83
7. Semin Musculoskelet Radiol. 2008 Jun;12(2):154-69
8. J Orthop Surg Res. 2016; 11(1): 97
9. North Clin Istanb. 2022; 9(1): 23–29
10. J Osteopath Med 2022; 122(5): 271–272
11. Clin. Anat. 23:613–621, 2010
12. J Orthop Surg Res. 2016 Sep 9;11(1):97