Exhibit 3.1

FOURTH AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

OF

K2M GROUP HOLDINGS, INC.

FIRST: The name of the Corporation is K2M Group Holdings, Inc. (the “Corporation”).

SECOND: The address of the registered office of the Corporation in the State of Delaware is 1209 Orange Street, Wilmington, County of New Castle, Delaware 19801. The name of its registered agent at that address is The Corporation Trust Company.

THIRD: The purpose of the Corporation is to engage in any lawful act or activity for which a corporation may be organized under the General Corporation Law of the State of Delaware, as amended from time to time (the “DGCL”).

FOURTH: The total number of shares of stock which the Corporation shall have authority to issue is 1,000 shares of Common Stock, each having a par value of one cent ($0.01).

FIFTH: The following provisions are inserted for the management of the business and the conduct of the affairs of the Corporation, and for further definition, limitation and regulation of the powers of the Corporation and of its directors and stockholders:

(1) Except as otherwise provided by the DGCL or this Amended and Restated Certificate of Incorporation, the business and affairs of the Corporation shall be managed by or under the direction of the Board of Directors.

(2) The directors shall have concurrent power with the stockholders to make, alter, amend, change, add to or repeal the By-Laws of the Corporation.

(3) The number of directors of the Corporation shall be as from time to time fixed by, or in the manner provided in, the By-Laws of the Corporation. Election of directors need not be by written ballot unless the By-Laws so provide.

(4) In addition to the powers and authority hereinbefore or by statute expressly conferred upon them, the Board of Directors is hereby empowered to exercise all such powers and do all such acts and things as may be exercised or done by the Corporation, subject, nevertheless, to the provisions of the DGCL, this Certificate of Incorporation, and any By-Laws adopted by the stockholders; provided, however, that no By-Laws hereafter adopted by the stockholders shall invalidate any prior act of the Board of Directors which would have been valid if such By-Laws had not been adopted.

SIXTH: Meetings of stockholders may be held within or without the State of Delaware, as the By-Laws may provide. The books of the Corporation may be kept (subject to any provision contained in the DGCL) outside the State of Delaware at such place or places as may be designated from time to time by the Board of Directors or in the By-Laws of the Corporation.

SEVENTH: The Corporation reserves the right to amend, alter, change or repeal any provision contained in this Certificate of Incorporation, in the manner now or hereafter prescribed by statute, and all rights conferred upon stockholders herein are granted subject to this reservation.

EIGHTH: To the fullest extent permitted by the DGCL as it now exists or may hereafter be amended, a director of the Corporation shall not be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty owed to the Corporation or its stockholders occurring at or prior to the effective time (the “Effective Time”) of the merger of Austin Merger Sub Corp., a Delaware corporation (“Merger Sub”), with and into the Corporation pursuant to the Agreement and Plan of Merger, dated August 29, 2018, by and among Merger Sub, Stryker Corporation and the Corporation. Neither the amendment nor repeal of this Article Eighth, nor the adoption of any provision of this Amended and Restated Certificate of Incorporation, nor, to the fullest extent permitted by the DGCL, any modification of law shall eliminate, reduce or otherwise adversely affect any right or protection of a current or former director of the Corporation existing at the time of such amendment, repeal, adoption or modification for any breach of fiduciary duty by such director occurring at or prior to the Effective Time.

* * * * *

2