Debridement Technique for Single-Stage Revision Shoulder Arthroplasty.

BACKGROUND

The incidence of revision shoulder arthroplasty continues to rise, and infection is a common indication for revision surgery. Treatment of periprosthetic joint infection (PJI) in the shoulder remains a controversial topic, with the literature reporting varying methodologies, including the use of debridement and implant retention, single-stage and 2-stage surgeries, antibiotic spacers, and resection arthroplasty. Single-stage revision has been shown to have a low rate of recurrent infection, making it more favorable because it precludes the morbidity of a 2-stage operation. The present video article describes a meticulous debridement technique as it applies to revision shoulder arthroplasty.

DESCRIPTION

The previous deltopectoral incision should be utilized, with extension 1 to 1.5 cm proximally and distally, removing any draining sinuses. First, develop subcutaneous flaps above the muscle layer to better establish normal tissue planes. A large medial subcutaneous flap will allow for identification of the superior border of the pectoralis major. The pectoralis can be traced laterally to its humeral insertion, which is often in confluence with the deltoid insertion. Hohmann retractors can be placed sequentially, working distal to proximal, under the deltoid in order to recreate the subdeltoid space. Next, reestablish the subpectoral space by releasing any scar tissue tethering the pectoralis muscle and conjoined tendon. Dislocate the prosthesis and remove modular components. Restore the subcoracoid space by dissecting between the subscapularis and the conjoined tendon, allowing for axillary nerve identification. Complete a full capsular excision circumferentially around the glenoid, taking care to protect the axillary nerve as it passes from the subcoracoid space under the inferior glenoid to the deltoid muscle. The decision to remove well-fixed components should be made by the surgeon. Any exposed osseous surfaces should undergo debridement to reduce bacterial burden. Reimplantation should focus on obtaining stable bone-implant interfaces to minimize any micromotion that may increase risk of reinfection. Our preference is to irrigate with 9 L of normal saline solution, Irrisept (Irrimax), and Bactisure Wound Lavage (Zimmer Biomet). Multiple cultures should be taken and followed carefully postoperatively to allow tailoring of the antibiotic regimen with infectious disease specialists.

ALTERNATIVES

Two-stage revision is the most common alternative treatment for shoulder PJI and consists of removal of components, debridement, and delayed component reimplantation; however, it requires at least 1 return to the operating room for definitive treatment.

RATIONALE

Serum laboratory studies and joint aspiration are not reliable predictors of shoulder PJI because of the high rate of infections. The incidence of unexpected positive cultures in seemingly aseptic revisions ranges from 11% to 52.2%. It is prudent for all revision shoulder arthroplasties to be treated as involving a presumed infection, with thorough debridement, because of the high rate of unexpected positive cultures and the greater prevalence of low-virulence organisms in shoulder arthroplasty for PJI.

EXPECTED OUTCOMES

The International Consensus Meeting guidelines for PJI were developed in 2018, and patients with higher Infection Probability Scores are theorized to have higher rates of recurrence. With meticulous debridement, the rate of recurrent infections requiring reoperation is just 5% following 1-stage revision shoulder arthroplasty, averaged across all Infection Probability Scores.

IMPORTANT TIPS

Ensure that an adequate incision is made in order to allow for identification of the deltoid origin on the clavicle and insertion on the humerus.The superior border of the pectoralis major can be traced laterally to the humerus to correctly identify the deltopectoral interval.Subdeltoid dissection is complete when you are able to identify deep deltoid fibers superficially, rotator cuff tendon posteriorly, and humeral bone. Exposure can be improved by abducting and internally rotating the humerus.Capsule excision around the glenoid is complete when the subscapularis can be visualized anteriorly, the fatty tissue of the inferior glenoid space inferiorly, and the rotator cuff tendon (or subdeltoid space if the cuff is absent) posteriorly and superiorly.

ACRONYMS AND ABBREVIATIONS

PJI = periprosthetic joint infectionC. acnes = Cutibacterium acnesUPC = unexpected positive cultureIS score = Infection Probability ScoreDAIR = debridement, antibiotics, and implant retentionCT = computed tomographyWBC = white blood cellCRP = C-reactive proteinESR = erythrocyte sedimentation rateCHG = chlorhexidine gluconateAC = acromioclavicularGT = greater tuberositySGHL = superior glenohumeral ligament.