Dr. John Stephen McMahon Dr. John Stephen McMahon Suite 306 377 Church Street Markham ON L6B 1A1 Phone: (905) 472-5375 Fax: (905) 472-5651 Return to Markham Surgeon Directory Report incorrect contact information For more information, check out the following; Joint-Injuries.com Joint-Replacements.ca SurgicalWaitTimes.com Private-Surgery-Canada.com OrthopaedicPhysiotherapy.com HomeCarePhysio.com TeleOrthopaedics.com