Arthroscopic Acromioplasty

Indications

Failed nonoperative management
primary mechanical impingement
in conjunction with management of
- partial thickness rotator cuff tears
- full thickness rotator cuff tears
Malunions of Greater Tuberosity < 1cm
- (> 1cm shoulder have osteotomy & ORIF)

Equipment

basic arthroscopic instruments
inflow pump
5.5 mm full radius resector
- subacromial decompression
arthrscopic burr
- hard bone
tissue ablator
- soft tissue removal & coagulation
Suture anchors available incase of Rotator Cuff Repair

Position

Options
- Lateral decubitus
  - 10 to 15 pounds of skin traction with shoulder in 30° of abduction & 20° of flexion
- Beach chair
  - Pros
    - ability to manipulate humerus during intra-articular examination
    - easy to convert to mini-open procedure
Drape arm free with screen easily visible
Use arthroscopy pump to maintain constant fluid flow to limit bleeding
Landmarks
- Acromion
- Corocoid process
- ACJ
- Clavicle
- Portal Sites
Perform EUA
- ROM
  - If stiff → manipulate
- Stability

Incision

Posterior portal (for viewing)

2cm inferior & 1 to 2cm medial to posterolateral corner of acromion
aim towards coracoid process

Lateral portal (for instrumenting)

3cm lateral to lateral border of acromion in line with posterior aspect of ACJ

Anterior Portal (if necessary)
- lateral to coracoid process

Diagnostic Arthroscopy

Inspect Glenohumeral joint
- Pathology
  - labral
  - articular surface
  - biceps tendon
    - look for synovitis superior to biceps insertion
    - often seen in rotator cuff pathology
  - synovitis
    - inferior to the biceps tendon
      - often seen in adhesive capsulitis
  - adhesive capsulitis
  - undersurface R/C pathology
    - Normal insertion of supraspinatus
      - <1mm from articular margin of humerus
      - along the anterior 2 cm of greater tuberosity
      - tendon thickness 14mm
    - Follow Biceps tendon along to the point it exits the joint
      - Tears are usally lateral to this point
      - Look for subluxation / dislocation of Biceps tendon
        
        Subscapularis tear
    - Mark any tears with spinal needle & PDS suture
- Especially useful in
  - < 40 years old
    - GH Instability
  - Dx Partial thickness R/C tear
  - Assessing reparability of Full thickness R/C tear

Acromioplasty

Enter SA space by advancing blunt trochar to just beneath acromion
To aid in visualisation
- sweep the trocar in a medial to lateral direction to break up any adhesions in the bursa
Establish lateral portal with needle
- 2cm distal to lateral border of acromion
- in line with posterior border of clavicle
- This position may be varied according to R/C tear
Remove bursa with shaver / tissue ablator to view from ACJ to R/C insertion
Use arthroscopic diathermy & to resect C/A ligament
- watch for the artery
Remove soft tissue from undersurface of acromion to identify anterior 2cm, anterolateral corner, & ACJ
Use arthroscopic burr to remove lateral edge of acromion just medial to portal
Remove full thickness of anterior acromion back to clavicle
leave deep fascia of deltoid intact
Taper acromioplasty from anterior to posterior using strokes of burr starting with about 5mm anteriorly
Can place burr through posterior portal to complete acromioplasty
Resect undersurface of ACJ if indicated from preop symptoms or x-rays
- Coplaning
Debride/repair R/C if required (arthroscopic or mini-open)
Close portals with interrupted sutures

Postop/rehabilitation

Sling for comfort
Pendula exercises immediately
1/52
- passive & active assisted range of motion
2/52
- light resistive exercises for rotator cuff using elastic tubing
3-4/52
- Full ROM should be achieved
4/52 - 3/12
- increasing strenghtening exercises
Return to Work
- Office : 1/52
- Sports & Heavy Labour: 2-3/12

Complications & Dangers

Intraoperative Bleeding
Residual Pain
- Reasons
  - missed adhesive capsulitis
  - AC joint arthrosis
  - fatigue from permanently weakened muscles
Anterior deltoid dysfunction

Axillary nerve injury
Detachment of deltoid from acromion

Synovial fistula
Acromial fracture
Postoperative Stiffness
- can be avoided with
  - adequate diagnosis & decompression
  - physiotherapy