Why is my son tip toe walking?

At 18 months of age my son started walking on his toes. It began gradually but now at 2 1/2 years of age he continues to walk on his toes all the time. When our pediatrician noticed this at the last visit, he referred us to an orthopedic specialist. I didn't think it was a big deal but the doctor said is could turn into a concern. We just the orthopedic doctor last week so Luke can get checked out. Dr. P told us that his son too was a toe walker and usually grow out of it but 5 years old. However, if this is indeed a sensory issue and he didn't grow out of it, there are options.

• First, a cast to help child adjust to walking on heels
• Second, seek physical therapy
• Third, if all fails surgery to the tendon.

Has anyone had this experience? If so, what was the outcome?