Association between Achilles tightness and lower extremity injury in children.

BACKGROUND: It is unclear whether isolated gastroc/soleus tightness can increase the risk of lower extremity injury in an otherwise healthy child.

QUESTIONS/PURPOSES: (1) Is there a difference in gastroc/soleus tightness, as represented by ankle dorsiflexion with the knee extended, in children presenting with upper versus lower extremity complaints? (2) Is there a difference in gastroc/soleus tightness in children presenting with atraumatic versus traumatic lower extremity complaints?

METHODS: We performed a cross-sectional study of 206 consecutive walking age children presenting to a county orthopedic clinic with new upper or lower extremity complaints. Passive ankle dorsiflexion was measured based on the lateral border of the foot versus the anterior lower leg with the knee fully extended and the foot in inversion.

RESULTS: Average age was 10.0 ± 4.5 years. In the 117 patients presenting with upper extremity complaints, ankle dorsiflexion was 15.0° ± 11.6°. Of the lower extremity patients, 40 presented without trauma, with dorsiflexion of 11.8° ± 14.5°, while 49 presented with trauma, with dorsiflexion of 6.5° ± 12.0°. Multiple regression analysis found significantly decreased ankle dorsiflexion with increasing age and in the lower extremity trauma group. Twelve percent of upper extremity patients had 0° or less of dorsiflexion, as compared to 25% of lower extremity nontrauma patients and 41% of lower extremity trauma patients.

CONCLUSIONS: Patients presenting with lower extremity trauma had significantly more gastroc/soleus tightness in their well leg than patients presenting with upper extremity complaints. Gastroc/soleus tightness may present a simple target for reducing lower extremity injury rates in children.