GLENOID COMPONENTS – POLYETHYLENE-METAL OR ALL POLYETHYLENE
In the absence of reliable evidence, it is the opinion of the workgroup that clinicians may use polyethylene-metal hybrid glenoid components or all-polyethylene components during total shoulder arthroplasty for treatment of glenohumeral joint osteoarthritis

Rationale

Recently, methods for improved glenoid fixation have been designed in order to decrease loosening rates and need for revision surgery. Hybrid glenoid polyethylene components include cages as well as addition of trabecular metal. Friedman et al. compared cemented all polyethylene glenoid implants to hybrid cage glenoid implants and found lower rates of aseptic loosening (1.3% hybrid vs 3.8% all polyethylene), as well as significantly lower revision rates in the hybrid cage group (2.5% vs 6.9%, P=0.0088). The authors did report 1.3% incidence of articular surface dissociation. Nelson et al. reported 5-year outcomes of hybrid glenoid component with a central porous titanium post and cemented peripheral pegs. The authors found 2.2% incidence of glenoid failure requiring revision and 20% classified as at risk for loosening. Overall concluding low rate of mechanical failure and successful clinical outcomes as measured by ASES score as well as functional range of motion. Finally, Watson et al. reported the results of trabecular metal backed glenoid components. The authors reported 25% rate of radiographic metal debris, 1 catastrophic failure and 11% revision rate at 2-year follow-up The authors concluded that this implant should be used with caution. It is clear that many new hybrid options are become available for clinical use with good clinical outcomes as relatively low complication rates.

 

Strength of Evidence (quality of evidence): No reliable evidence

 

Benefits & Harms:

Early studies demonstrate that at short term follow up hybrid glenoid components have been safe with low complication and revision rates.

 

Outcome Importance:

Functional and patient reported outcomes related to the use of hybrid glenoid components as well as safety profile with survivorship, modes of failure and incidence of revision surgery as compared to standard all polyethylene glenoid implants.

 

Cost Effectiveness/Resource Utilization:

Cost analysis investigation still remains to be performed as commonly newer technology can be more expensive.

 

Acceptability:

These implants are becoming increasing more popular for clinical use so there seems to be no barriers to implementation for the use of these glenoid components.

 

Feasibility:

Hybrid glenoid components are already used in clinical practice for treatment of glenohumeral joint osteoarthritis during anatomic total shoulder arthroplasty.

 

Future Research:

 Future high quality comparative long-term outcomes studies need to be performed to determine the impact of hybrid glenoid fixation on implant survivorship. This data can provide guidance as to which patients should be indicated for the use of hybrid glenoid components during anatomic total shoulder arthroplasty. Additionally, can follow the influence of glenoid deformity as well as rotator cuff pathology on outcomes and implant survivorship.
 

Additional References:

Friedman, R.J.Cheung, E.Grey, S.G., et. al. Clinical and radiographic comparison of a hybrid cage glenoid to a cemented polyethylene glenoid in anatomic total shoulder arthroplasty. J Shoulder Elbow Surg. 2019;28(12):2308-2316.

Nelson, C.G.Brolin, T.J.Ford, M.C.Smith, R.A.Azar, F.M.Throckmorton, T.W., Five-year minimum clinical and radiographic outcomes of total shoulder arthroplasty using a hybrid glenoid component with a central porous titanium post. J Shoulder Elbow Surg. 2018;27(8):1462-1467.

Watson, S.T., Gudger, G.K., Long, C.D., Tokish, J.M., Tolan, S.J. Outcomes of Trabecular Metal-backed glenoid components in anatomic total shoulder arthroplasty. J Shoulder Elbow Surg. 2018;27(3):493-498.