As part of the Western Foot and Ankle Conference’s pediatrics track, Jarrod Shapiro, DPM, FACFAS tackles the question of “Achilles Tendon Lengthening: Is It Really Necessary?” Podiatry Today had the chance to talk with him regarding his lecture, and key points he’d like podiatrists to know.

In what circumstances do you feel posterior muscle group lengthening is necessary and effective in the pediatric population?

Dr. Shapiro shares that the primary indication for posterior muscle group lengthening is in children with spastic conditions, such as cerebral palsy.

“In very rare cases, pediatric toe walking may require Achilles tendon lengthening or gastrocnemius recession,” he says. “However, in my opinion, posterior muscle group lengthening is not indicated for most reconstructive surgery in either children or adults.”

He says the reason for this opinion runs counter to contemporary theory, which describes gastrocnemius equinus as a pathological contracture.

“I respectfully disagree with this entire paradigm and believe a different perspective is more accurate,” explains Dr. Shapiro, who postulated this view in a January 2020 paper in Clinics in Podiatric Medicine and Surgery.¹ “As a short summary, what we measure during the Silfverkiöld test as gastrocnemius equinus is a product of a nonpathological limitation of muscle range of motion seen in all muscles in the human body that cross more than one joint. When the proximal joint is extended, this uses up the available motion of the muscle causing decreased motion in the distal joint, termed passive insufficiency. This normal muscle acts on an abnormal foot (for example, in patients with pronatory hindfoot disorders), causing the otherwise normal gastrocnemius muscle to abnormally pronate the subtalar joint.”¹

What challenges do you feel clinicians face when working up equinus in the pediatric population?

Dr. Shapiro says that perhaps the greatest challenge is when a child presents with an otherwise normal history and exam, but with minor complaints such as painless intoeing that do not affect function. He adds that these cases may require ample time to address the concerns of the parents or guardians if advocating for a “watch and wait” approach.

“Podiatrists are often the first specialists to see pediatric patients with equinus-related complaints such as toe walking or falls,” he says. “With a proper detailed history, including perinatal and postnatal history as well as achieving milestones, coupled with a comprehensive physical examination that includes a detailed neurological screening and a biomechanical exam, the diagnosis of equinus is not difficult in patients with neurological disorders.”

He adds that findings including delayed onset of milestones and/or a history of falls coupled with a physical examination demonstrating a cavus or cavovarus deformity with an abnormal neurological exam (such as the presence of sustained clonus) should clue the astute doctor into a concerning pathology.

What one pearl or tip from your lecture would you like to share with the audience that they can enact in their practices today?

“Stop using the Silfverskiöld examination to test for the diagnosis of equinus,” he answers. “Assume equinus is present in the majority of patients, eliminating those patients who have elongated muscle/tendons due to stretching (such as in dancers and athletes) or those with hypermobility disorders (such as Marfan’s or Ehlers Danlos). Instead, use this test to determine the severity of tightness, especially in those patients with neurological causes of excessive plantarflexion, as Dr. Silfverskiöld did in his original article."²

Is there anything else you’d like to add?

Dr. Shapiro relates that one takes the view that non-neurological gastrocnemius equinus is not pathological, but is rather a normal muscle acting on a pathological foot. This causes a potential change in approach to many pathologies.

“For example, if a child with a flatfoot deformity is found to have a medially deviated subtalar joint axis, then a medial displacement calcaneal osteotomy or an Evans procedure are better choices, as they return the gastrocnemius to its proper function as an inverter of the calcaneus now that it is medial to the subtalar axis,” he says. “Weakening an otherwise strong gastrocnemius-soleus muscle would now be contraindicated. More research needs to be done to further validate this perspective, but much of the current literature implicating equinus as an etiologic factor in foot disorders must come into question.”

Dr. Shapiro relates no relevant disclosures to his lecture.

References

1.     Shapiro J, Kamel B. Passive muscular insufficiency. The etiology of gastrocnemius equinus. Clin Podiatr Med Surg. 2020;37:61-69.

2.     Silfverskiold N. Reduction of the uncrossed two-joints muscles of the leg to one-joint muscles in spastic conditions. Acta Chirug Scand.1924;56:315.