Method and apparatus for performing a less invasive shoulder procedure

1. A method for performing an arthroplasty on at least one of a glenoid or a humerus of a glenohumeral joint comprising:

forming an entry incision in soft tissue superior and lateral to the glenohumeral joint;

forming a passage from the entry incision to the glenohumeral joint;

inserting a cutting instrument through the passage and cutting a natural humeral head of the humerus to prepare the humerus to receive an implant including a stem while the humeral head has no dislocation at all with respect to the glenoid and remains in its anatomical position;

inserting the implant through the passage, and securing the implant relative to the humerus with the implant oriented such that a longitudinal axis of the stem extends substantially parallel to a longitudinal axis of the humerus; and

maintaining both a subscapularis muscle and a supraspinatus muscle associated with the glenohumeral joint intact and completely connected to surrounding bone during an entirety of the arthroplasty.

2. The method of claim 1 , further comprising: forming only a single entry incision.

3. The method of claim 1 , further comprising: forming the passage through a deltoid muscle substantially superior and lateral of the glenohumeral joint.

4. The method of claim 1 , further comprising: inserting through the passage the implant including an articulation surface.

5. The method of claim 1 , further comprising: inserting through the passage the implant including an articulation surface, a first axis extending through an axial center of the articulation surface, a planar coupling surface that lies in a plane that is perpendicular to the first axis, and a second axis extending through an axial center of the stem, the second axis is non-orthogonal to the coupling surface.

6. The method of claim 1 , wherein securing the implant relative to the humerus further comprises: impacting the implant along a first axis that is generally parallel to a second axis, the second axis is a longitudinal axis of the intramedullary canal of the humerus.

7. The method of claim 1 , further comprising:

inserting a reamer through the entry incision;

reaming the glenoid with the reamer;

inserting a glenoid implant through the passage; and

securing the glenoid implant to the glenoid.

8. A method for performing an arthroplasty on at least one of a glenoid or a humerus of a glenohumeral joint comprising:

forming an entry incision in soft tissue superior and lateral to the glenohumeral joint;

forming a passage from the entry incision to the glenohumeral joint through a deltoid muscle substantially superior and lateral of the glenohumeral joint;

inserting a cutting instrument through the passage and cutting a natural humeral head of the humerus while the humeral head is in cooperation with a glenoid, has no dislocation at all with respect to the glenoid, and remains in its anatomical position to prepare the humerus to receive an implant;

inserting through the passage the implant including an articulation surface with a first axis extending through an axial center of the articulation surface, a planar coupling surface that extends in a plane orthogonal to the first axis, and a stem with a second axis extending through an axial center of the stem and substantially parallel to a longitudinal axis of the stem, the second axis is non-orthogonal to the coupling surface and is substantially parallel to a longitudinal axis of the humerus;

orienting the implant such that the second axis is substantially parallel to a longitudinal axis of an intramedullary canal of the humerus;

securing the implant relative to the humerus; and

maintaining both a subscapularis muscle and a supraspinatus muscle intact during an entirety of the arthroplasty procedure.

9. The method of claim 8 , further comprising: forming only a single entry incision.

10. The method of claim 9 , further comprising: forming the passage to extend from the single entry incision to the glenohumeral joint generally interiorly and toward a sagittal plane of a patient.

11. The method of claim 8 , further comprising: resecting a portion of the humeral head while the humeral head is in cooperation with the glenoid.

12. The method of claim 8 , further comprising: inserting through the passage the implant, the stem of the implant including a first coupling member that is offset from a second coupling member.

13. The method of claim 8 , further comprising: inserting through the passage the implant, the stem of the implant is modular.

14. A method for performing an arthroplasty on at least one of a glenoid or a humerus of a glenohumeral joint comprising:

forming an entry incision in soft tissue superior and lateral to the glenohumeral joint;

forming a passage from the entry incision to the glenohumeral joint through a deltoid muscle substantially superior and lateral of the glenohumeral joint;

inserting a cutting instrument through the passage and cutting a humeral head of the humerus while the humeral head is in cooperation and undislocated with a glenoid to prepare the humeral head to receive an implant including an articulation surface and a stem;

resecting at least a portion of the humeral head while the humeral head is in cooperation with the glenoid;

inserting the implant through the passage, and securing the implant relative to the humerus with the implant oriented such that the stem is confined to an area superior to an intramedullary canal of the humerus and a longitudinal axis of the stem extends substantially parallel to a longitudinal axis of the humerus; and

maintaining a subscapularis muscle and a supraspinatus muscle proximate to the glenohumeral joint intact and completely connected to surrounding bone during the entire arthroplasty procedure.

15. The method of claim 14 , further comprising: forming only a single entry incision during the entire arthroplasty procedure.

16. The method of claim 14 , further comprising:

performing the entire arthroplasty without resecting and without incising the subscapularis muscle and ligaments associated with the subscapularis muscle; and

performing the entire arthroplasty without resecting and without incising the supraspinatus muscle and ligaments associated with the supraspinatus muscle.

17. The method of claim 14 , wherein securing the implant relative to the humerus further comprises: impacting the implant along an axis that is generally parallel to a longitudinal axis of the humerus.