Gelsyn-3 Gelsyn-3 is used to treat knee pain, is a fluid injected into the knee that acts as a lubricant and shock obsorber for joints. Gelsyn-3 Benefits: Gelsyn-3 provides pain relief to patients that are not getting satisfactory relief from pain relievers or exercise and rehabilitation. Make an Appointment 973-377-6700 Address 345 Main St., Madison NJ Follow Us Facebook