Twyman was born and raised in Pittsburgh, Pennsylvania, where he attended Central Catholic High School (which also produced Pro Football Hall of Fame Quarterback Dan Marino).

[1][2] After graduating from Central Catholic High School, Twyman attended the University of Cincinnati, where he received his degree in elementary education and averaged 24.6 points and 16.5 rebounds in his Bearcat career.

Twyman made a call during game 7 of the 1970 NBA Finals between the New York Knicks and the Los Angeles Lakers.

During the pre-game segment with Schenkel, Twyman noticed Knicks' injured center Willis Reed (whose status for the clincher had been doubtful) advancing from the tunnel toward the court.

"[6] The sight of Reed marching toward the basketball floor helped inspire the Knicks to a 113–99 victory – one that gave New York its first NBA league title.

Twyman became the legal guardian of his teammate and friend Maurice Stokes, a Hall of Fame player who was paralyzed due to a head injury he suffered after a fall during a game.

In the last game of the 1958 regular season, Stokes was knocked down on a play and hit his head on the floor, which rendered him unconscious.

[10] The game became a decades long annual event, attracting many of the top players in the NBA, and was later replaced by a pro-am golf tournament.

[11] Twyman helped Stokes to obtain workers compensation and taught him to communicate by blinking his eyes to denote individual letters.

[12][18] Twyman was survived by his wife of 57 years Carole, his son, Jay; three daughters, Julie, Lisa and Michele; and 14 grandchildren.