Arthroscopic Removal of the Polyethylene Glenoid Component After Total Shoulder Arthroplasty: A Systematic Review

Loosening of the glenoid component is the most common reason for revision after total shoulder arthroplasty (TSA) and may be responsible for 30% of revision procedures.^1–3 While TSA continues to be a frequently performed and effective treatment option for pain relief and improvement of function for degenerative shoulder conditions there remains concerns regarding implant longevity.^4–7 A recent population-based cohort study has estimated the lifetime revision rate for a failed primary TSA to be as high as 25%.⁸ International joint replacement registries also have shown a rapidly growing number of shoulder arthroplasty procedures and future revision rates for TSA will likely be affected by this increase in primary volume.^9,10

Several treatment options have been proposed for glenoid loosening, including glenoid bone grafting, open conversion to a hemiarthroplasty, revision glenoid implantation and conversion to reverse total shoulder arthroplasty (RTSA).¹¹ However there is currently no consensus on the optimal surgical technique, as all of these proposed methods have been shown to have varying complication and reoperation rates.^1,12–15 Arthroscopic removal of the glenoid component (ARGC) after TSA has been proposed as an option for presumed aseptic polyethylene loosening (Figures 1 and 2).¹⁶ Proposed advantages of this technique include a less-invasive arthroscopic approach, which may be beneficial in older patients with multiple medical comorbidities due to the potential to avoid some complications associated with open revision.^17–19 Although open revision TSA techniques have been well studied, there remains a paucity of literature related to indications, outcomes and complications related to ARGC after TSA.

The purpose of this systematic review was to identify prior clinical series related to ARGC after TSA to better define indications, complications, and outcomes related to the procedure. We aimed to describe the clinical and PROMs that were previously published on this technique. We hypothesized that ARGC can be a useful operative technique for the revision of a failed primary TSA due to aseptic osteolysis of the polyethylene glenoid component.

Institutional Review Board exemption was obtained for this study. The paper follows the transparent reporting guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist.

There was a total of 768 articles identified for review. Figure 3 illustrates article inclusion and exclusion for this investigation (Figure 3). After review of abstract and title, 50 articles were included for full text review. After applying exclusion criteria, a total of 6 articles were included in the final review (Figure 3). Of the 6 included articles, 2 were case reports, 3 were retrospective case series and 1 was a retrospective cohort study. A total of 25 cases of ARGC after TSA were identified across the included articles, the largest of which included 12 cases. An overview of information available within the clinical articles in presented in Table 2 (Table 2).

Our systematic review identified six clinical articles (25 cases) reporting on outcomes after ARGC after TSA (Figures 6 to 8). At the time of final follow-up (56 months) Brochin et al reported a decrease in VAS pain scale and an increase in ASES score.¹⁷ Raphael et al retrospectively compared outcomes of glenoid open and arthroscopic glenoid removal to revision reimplantation procedures.²⁰ They reported improved Constant and UCLA scores for 5 of their patients that underwent ARGC and there were no statically significant differences between resection and reimplantation.²⁰ Additionally, O’Driscoll et al reported that all five patients in their series had improved pain after ARGC and stated that all the patients in their study would choose the same procedure again.¹⁶ The outcomes of different revision techniques to address glenoid component loosening have also been reported on in previous studies. In their study comparing the outcomes of open conversion glenoid resection to reimplantation, Aibinder et al reported no significant differences in the outcomes between the two groups.²¹ Cheung et al reached a similar conclusion in their comparative study but additionally reported a slight improvement in active elevation for the reimplantation group.²² A previous systematic review has also identified improved PROMs, mainly in pain scale, ASES and Constant scores, for both revision TSA and conversion to RTSA after a failed index TSA.¹ Findings from this current systemic review indicate similar improvement in pain relief and PROMs after ARGC.

A proposed benefit of ARGC after TSA is that it may be less invasive (and potentially less morbid than open revision). This systematic review found that in primary clinical articles related to ARGC after TSA, complications were infrequently reported. Twenty patients were evaluated for postoperative complications. One patient (5%) had exacerbation of their pre-existing lymphedema.^16,17 Two patients 2 patients (10%) had persistent pain postoperatively and underwent conversion to RTSA.^16,17 None of the publications in our review reported any intraoperative complications for these reoperations. In addition to ARGC after TSA, several revision options such as conversion to RTSA, open conversion to hemiarthroplasty, and component re-implantation for aseptic glenoid component loosening exist. Previous publications on these revision options have shown variable rates of complications and reoperations. Additionally, a larger retrospective series with 127 shoulders focusing on conversions to RTSA reported a 29% rate of intraoperative complication and 20% reoperation rate.¹³ A complication rate of 35% and a 29% reoperation rate was reported by another retrospective study that outlined outcomes of open revision hemiarthroplasty for aseptic glenoid component loosening.¹⁴ A higher reoperation rate of 67% for glenoid component revision has also been reported.¹⁵ Additionally, a systematic review of 3843 failed index TSAs undergoing either revision TSA or conversion to RTSA reported a 20% postoperative complication and a 13% re-operation rate.¹ It is worth noting that the leading cause for re-operation in these studies was recurrent loosening of prosthetic components and instability.^1,12–15 Our review shows lower reported complications and revision rates for ARGC when compared to other operative modalities for treating aseptic glenoid component loosening.

The findings in this systematic review indicate that ARGC has historically been performed for older patients (mean age of 75). A plethora of factors such as infection, instability, loosening and the status of the rotator cuff can impact the management of a failed primary TSA.²³ Even though re-implantation of the glenoid component may have potential advantages, open revision procedures can introduce substantial risk particularly for elderly patients with multiple medical co-morbidities.²⁴ Prior studies have indicated that patients undergoing re-implantation and conversion to RTSA may have less-advanced arthritic disease and higher baseline levels of function than those undergoing ARGC.²⁰ Several examples from our findings support this trend. O’Driscoll performed this procedure in patients with morbidity obesity, difficult index procedure exposure, large rotator cuff tears, and other those with severe medical co-morbidities.¹⁶ In their series, Raphael et al indicated that the resection group had more prior surgeries and lower functional demands.²⁰ Additionally, they stated that ARGC was performed in patients with insufficient glenoid bone stock.²⁰ In this context, ARGC might be better reserved for patients who have a lower baseline functional demands or may be at higher risk for surgical morbidity with open revision procedures in patients with co-morbidities. In addition, considering that ROM does not appear to substantially change postoperatively, ideal candidates for this procedure would have pain as a main complaint and should be satisfied with their preoperative ROM.

This study has a number of limitations which should be considered. Overall, there were a limited number of articles (6) and included patients (25). Patient baseline demographics and PROMs were inconsistently reported, making comparisons across clinical series difficult. Furthermore, the included articles overall contained lower levels of evidence, and in the absence of large comparative series, making comparisons between different revision techniques can be difficult.

Our systematic review identified 6 articles that reported on the outcomes of ARGC for aseptic loosening after TSA. The included clinical series indicate that ARGC can improve pain and functional outcomes in appropriately selected patients. At present, patients undergoing ARGC appear to be older, have lower functional demands and may be at risk for medical complications with open revision. ARGC after TSA has a low rate of subsequent reoperation (8%) and has the potential to avoid some of the complications associated with open revision arthroplasty procedures. As a less-invasive arthroscopic technique, ARGC after TSA may be an alternative to open revision for lower demand patients; however, future prospective, comparative studies are necessary to better define indications and outcomes.