Expandable fusion devices and methods of installation thereof

An intervertebral implant, comprising:

• a first endplate having an upper surface and a lower surface, wherein the first endplate comprises a first side wall that extends from the first endplate;
• and
• a second endplate having an upper surface and a lower surface, wherein the second endplate includes a second side wall that extends from the second endplate;
• an engagement mechanism for engaging the first sidewall to the second sidewall and configured to provide a selective height between the first endplate and the second endplate;
• and
• a fixation member capable of engaging an adjacent vertebra,
• wherein the engagement mechanism comprises an opening for receiving the fixation member to secure the implant to the adjacent vertebra,
• wherein the first side wall and the second side wall are configured to engage one another and provide a selective height between the first endplate and the second endplate;
• wherein the first side wall and the second side wall form a substantially hollow portion substantially enclosed by the first endplate, second endplate, first side wall and the second side wall;
• and
• wherein the substantially hollow portion is configured to receive bone growth inducing material,
• a drive plate provided within an end cap, the drive plate comprising a first spike configured to advance from the drive plate and engage with a vertebral body for securing the intervertebral implant to a vertebral body above the first endplate, and a second spike configured to advance from the drive plate and engage with a vertebral body for securing the intervertebral implant to a vertebral body below the second endplate.