Rockwood Adults CH34

1104

SECTION TWO • Upper Extremity

Potential Pitfalls and Preventive Measures

Anterior Glenohumeral Instability: SURGICAL PITFALLS AND PREVENTIONS Pitfall Arthroscopic Bankart Repair • The lowest anchor position too high on the glenoid face is a risk factor for failure (needs to be 5 to 5:30 on the right shoulder and 6 to 6:30 on the left shoulder) • Glenoid rim anchor position on the glenoid neck or below the rim • Loss of fixation with the anchor or glenoid rim fracture • Inadequate capsulolabral shift resulting in persistent instability • Difficulty passing the anterior and lowest suture passers across the capsulolabral tissue

Prevention

• Get the anteroinferior portal right above the subscapularis tendon in the low 5:30 position. • If the portal is high, a curved all-suture anchor with a curved guide can be used to get low on the glenoid rim. Alternatively, a trans-subscapularis percutaneous portal can be established for placement of the anchor at the most inferior position on the anterior glenoid. • The glenoid drill holes and anchor fixation need to be on the rim or slightly on the glenoid face to allow for optimal shifting of the anteroinferior capsulolabral tissue. • Use a bigger anchor in the same hole or alternatively; drill a separate hole in a difference location on the glenoid rim to avoid the perforated region. • The capsulolabral tissue must be mobilized off the glenoid rim with either a CoVator or arthroscopic elevator to visualize the muscle belly of the subscapularis. • Use a tissue grasper in the anterior lateral portal to help manipulate and shift the capsulolabral tissue to assist in the passing of the low inferior passer and suture. Alternatively, passage from the posterior portal using a suture lasso facing the opposite direction (i.e., left lasso for right shoulder) may facilitate passage at the most inferior position of the anterior labrum. • The anterior-inferior portal is right over the subscapularis tendon and the anterosuperior lateral portal is right underneath the anterior lateral edge of the acromion. Two threaded cannulas are inserted into the joint to allow suture passage. • Use a 70-degree scope in the posterior portal instead of the 30-degree scope to help visualization. Alternatively, the 30-degree scope can be switched over to the anteriosuperior lateral portal to view and work through the anterior-inferior portal to mobilize. This is especially important for anterior labral periosteal sleeve avulsion (ALPSA) lesions where the labrum is scarred in medially on the glenoid neck. • Either subscapularis peel or tenotomy can be used for the open Bankart procedure. The capsule must be separated away from the subscapularis tendon to allow for shift and repair with the Bankart lesion. Using an anterior Bankart retractor will help with the visualization. • After the Bankart repair, if anterior capsular shift is desired, it must be done with the arm in 30 degrees of forward flexion and 30 degrees of external rotation to avoid overtightening and loss of motion. • Use retractors that are smooth or place sterile lap sponge around the retractor to minimize damage to the humeral head during this procedure. • Place a curved smooth cobra retractor under the inferior glenoid rim to retract the axillary nerve away from the surgical site and avoid injury. • Medially place an anterior Bankart retractor, inferiorly place a smooth curved cobra retractor, superiorly use a 3-mm smooth pin to retract the subscapularis muscle belly, and a humeral head retractor in the glenohumeral joint. • Use 90-degree saw blade, cut from medial to lateral at the coracoid base to maximize the length, and complete the osteotomy with a curved osteotome. • Both fully threaded or partially threaded screws can be used for fixation. Typically, in most patients, a 30–32-mm screw will be the optimal length. If you are concerned that the screw length is too long, then after the graft is fixed down with the first screw, use a depth gauge to measure the second hole for the correct length. • Place a threaded Steinman pin or arthroscopic threaded tap into the coracoid base harvest site. Use the pin or tap to retract the scapula body posterior to allow better angle to drill the glenoid so that the screws are in optimal position. • Use a horizontal subscapularis split in the middle and then a vertical capsulotomy to get exposure. The subscapularis split will decrease the risk of subscapularis rupture or weakness compared with a tenotomy.

• Instrument crowding within the glenohumeral joint

• Difficulty with visualization of the anterior inferior labrum for mobilization and shifting/ repair

Open Bankart Repair • Difficulty with visualization of the anterior inferior Bankart tear

• Overtightening of the capsule resulting in stiffness and loss of external rotation

• Humeral head cartilage damage from retraction

Open Latarjet Procedure • Axillary nerve injury

• Lack of exposure

• Coracoid too short

• Screw too long

• Difficulty with the glenoid drill angle and placement of the screws parallel to the glenoid face

• Subscapularis tendon rupture