Shoulder Arthrodesis

General

  • 80-95% patient satisfaction in older studies
  • Union rates ~ 95%

Indications

  • Infection
    • GHJ unresponsive to nonoperative treatment
  • Stabilization
    • Paralytic disorders
    • Post-traumatic brachial plexus palsy
    • Irreversible flail shoulder
    • Recurrent dislocations despite reconstructions
  • massive, unreconstructable cuff ruptures
  • After resection for neoplastic lesions
  • Arthritic dseases unsuitable for arthroplasty
  • Salvage of failed GHJ arthroplasty
  • Alternative when arthroplasty contraindicated
  • Functional shoulder girdle muscles are prerequisite for satisfactory result

Advantages

  • Permanent solution

Disadvantages

  • Loss of movement at shoulder
  • Difficulty with activities at head level or behind the back
  • Perineal care
  • Feeding
  • Loss of movement at other joints
  • Prolonged immobilization

Position

  • Should achieve ability to reach mouth
  • With scapula in reduced position & in reference to trunk
    • 30° abduction
    • 30° flexion
    • 30° internal rotation
  • Technically difficult to obtain correct position intraoperatively
  • Preoperative brace to obtain position intraoperative OR
  • Preoperative XR with arm in desired position & compare with intraoperative XR
  • Ensure intraoperatively that flexion of elbow allows tip of thumb to strike chin

Principle

  • Rigid fixation with compression of a large surface area of bleeding cancellous bone

Options

  • Intra-articular
  • Extra-articular
  • Combined

Technique

  • Lateral decubitus position
  • Make incision over
    • Spine of scapula
    • Acromion
    • Proximal 1/3 of humerus
  • Strip deltoid (axillary nerve can be sacrificed) & cuff & expose
    • Spine of scapula
    • Glenoid fossa
    • Proximal humerus
  • Rotator cuff is resected
  • Denude glenoid & humeral head
  • Decorticate undersurface of acromion & lateral part of humerus
  • Displace humeral head superiorly & medially
  • Contact denuded glenoid & acromion
  • Position head in desired position
  • Can temporarily fix position & obtain XR
  • Compare with pre-op XR in desired position
  • Apply first standard broad AO plate (4.5mm DCP)
    • Superiorly along scapular spine, acromion & proximal third of humerus
    • 2 screws should pass through humeral head into glenoid through the plate
    • Can use separate lag screws
  • Apply second plate if unstable with 1 plate
    • Posteriorly from scapular spine to humerus
  • Apply bone graft if necessary
  • Postop
    • Splint vs spica
    • Plate not removed for 12-18 months