- beach chair position is comfortable for both the patient and the surgeon and allows the option of converting to an open procedure (if necessary);
- patients need to be seated with the torso raised to 70 deg with a foled sheet placed on the medial border of the affected scapula (to maximize posterior exposure)
- simultaneously palpate posterolateral corner and anterior of the acromion and note the "arthoscopic plane";
- if this plane is sloped too steeply, then the surgeon will have to hold the arthroscope in an awkward position (w/ the scope pointing upwards);
- to remedy this problem, increase the patient's sitting angle which will bring the arthroscopic plane down to a more horizontal level;
- complications: hypoglossal nerve injury;
- reference:
Hypoglossal nerve palsy after arthroscopy of the shoulder and open operation with the patient in the beach-chair position. A case report.
- Portal Placement:- generally arthroscopy of the shoulder joint is carried out prior to arthroscopic acromioplasty, and therefore, standard anterior and posterior arthroscopic portals are established;
- a self sealing cannula is usually placed thru the anterior portal;
- anterior portal:
- the arthroscope is driven anteriorly until the tip can be palpated near the anterior portal;
- drive the arthroscope thru the anterior portal and then pull the scope back out of its cannula;
- the arthroscopic cannula serves as a positioning guide for the anterior cannula which is then driven into the subacromial space;
- a 5.5 mm shaver is placed into the anterior portal cannula and an inital arthroscopic bursectomy is carried out;
- one adequate visualization of the subacromial space has been established, the lateral portal is established;
- lateral portal: (see portal placement);
- used as the main instrument portal (acromioplasty and bursal debridement);
- lateral portal is inserted in the usual manner with care that its placement will allow full triangulation of the undersurface of the anterior acromion;
- make sure that an 18gauge needle can get to the anteroinferior edge of the acromion and that it can be directed upwards for easier shaving;
- if the portal is positioned too close to the acromion, resection of the anteromedial aspect of the acromion will be difficult;
- Plan to Control Bleeding:
- pre-inject the subacromial space with 30 cc of 1:300,000 epinephrine solution;
- if possible, have anesthesia lower the patient's blood pressure;
- ensure that reserve fluid bags are present;
- arthroscopic techniques:
- when the posterior subacromial portal is established, bluntly sweep the trocar across the undersurface of the acromion which helps to remove the bursal attachments;
- minimize the use of the shaver to clear off the bursa, since this may stir up early bleeding;
- use cautery or the arthrocare wand to carefully define the undersurface landmarks of the acromion;
- be careful not to disturb the deltoid fascia which lies below the acromion since this is guaranteed to stir up bleeding;
- air injection:
- if bleeding obstructs the visualization, then shut off inflow and suction out the fluid;
- inject 100 cc of air thru a syringe;
- bleeding will then usually stop spontaneously