Humeral resection guides, and related methods, for use in tissue sparing shoulder arthroplasties

A resection guide, comprising:

• a superior radial arm having a proximal portion with at least one bone pin receiving opening formed therein and a distal portion configured to contact a humeral head of a humerus with the distal portion extending from the proximal portion in a direction towards a posterior portion of the humeral head, and a superior surface of the proximal portion of the superior radial arm defining a resecting plane of the resection guide;
• a guide slot formed on the superior radial arm, the guide slot being defined by a ledge of the distal portion of the superior radial arm extending over the superior surface of the proximal portion of the superior radial arm, and the guide slot being configured to receive a cutting instrument therethrough and guide the cutting instrument along the resecting plane while cutting the humeral head, keeping the cutting instrument one of parallel or substantially parallel to the resecting plane;
• and
• a vertical alignment plate extending distally from the superior radial arm, a length of the vertical alignment plate and the superior surface of the proximal portion of the superior radial arm forming an angle therebetween that is approximately in a range of about 125° to about 145°, the angle defining a resecting angle of the resection guide, and thus an angle of the resecting plane of the resection guide.