Medical conditions and medications can cause a buffalo hump on the neck, according to Healthline. Extreme obesity, osteoporosis and Cushing's syndrome are some medical conditions that cause a buffalo hump. Long-term use of steroids and medications that treat arthritis and asthma can lead to a buffalo hump, notes Hunstad Kortesis.
A buffalo hump is a fatty growth that develops on the neck, explains Healthline. The hump may also develop as the result of a tumor or cyst. Treatment of a buffalo hump involves identifying and treating the underlying condition. Surgical removal is an option, but unless the root cause of the buffalo hump is addressed, the hump may redevelop.