Survivorship of Trabecular Metal Anchored Glenoid Total Shoulder Arthroplasties

Abstract

Trabecular metal anchored glenoids (TMAGs) were developed to counter the pervasive problem of component loosening at the bone-cement interface in total shoulder arthroplasty. Increased failure rates associated with the glenoid component have been previously reported due to increased rates of glenoid failures. Our hypothesis was that in our patients, the failure rate of TMAG implants is similar to or less than reported failure rates of traditional all polyethylene glenoid components. A medical chart review of 66 consecutive patients treated with a TMAG total shoulder replacement was conducted including clinical and radiographic follow-up. Paired t test analyses were used to compare the patients' preoperative and postoperative shoulder range of motion. Patients on average had 50.2 months of clinical follow-up available. Although the radiographs of several patients demonstrated focal areas of lucency, none of the patients demonstrated evidence of glenoid loosening. Glenoid component failure was a rare occurrence, happening only once in the 66 patients (1.5%). The patient with a glenoid fracture sustained that complication 6 years after her index total shoulder replacement. She was the only patient in the series who required revision surgery. Most patients experienced significant improvements in their shoulder range of motion, improving forward flexion from 73.7 to 144.2 degrees (P<0.0001), internal rotation from L5 to T8 (P<0.0001), and external rotation 12.8 to 48.9 degrees (P<0.0001). With improved implant design and meticulous surgical technique, recent iterations of TMAG components do not produce excessive failure rates but result in significant functional improvements.

Loosening and revision rates after total shoulder arthroplasty: a systematic review of cemented all-polyethylene glenoid and three modern designs of metal-backed glenoid

“…1). The final cemented PEG group included 3312 patients (25 articles) , and the modern MBG group included 457 patients (10 articles) [4][5][6][37][38][39][40][41][42][43].…”

Modern trabecular metal-backed glenoid components in total shoulder arthroplasty: What is the evidence? A systematic review

“…Among those, 62 duplicate articles were identified and removed from the search. Following elimination of duplicate articles and predetermined exclusion criteria, seven articles were included for analysis 19–25 (Figure 1).

Figure 1.Flow chart of study selection according to PRISMA guidelines for reporting systematic reviews and meta-analyses.

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“…Among those, 62 duplicate articles were identified and removed from the search. Following elimination of duplicate articles and predetermined exclusion criteria, seven articles were included for analysis [19][20][21][22][23][24][25] (Figure 1).…”

“…All the studies of the current review had a level of evidence IV with one study being prospective 24 and the rest of them retrospective. [19][20][21][22][23]25 All studies were characterized by selection, detection, and performance bias, while relevant conflict of interest was found in three of them. 20,21,24 The overall mean modified Coleman score was 56.4/100 and ranged from 45/100 20 to 67/100 22 (Table 2).…”

Radiographic and clinical outcomes of second generation Trabecular Metal™ glenoid components in total shoulder arthroplasty

“…Short-term clinical studies investigating the performance of the second generation TM glenoid have yielded good to excellent patient outcomes; however, the majority of these studies only reported outcomes at a minimum two-year follow-up. 9,[13][14][15][16] Furthermore, short-term reports of radiographic metal debris formation associated with these components have shed a cautionary light and raised concern for possible future implant failure. 14,16 In the current literature, five-year or greater follow-up outcomes of the second generation TM glenoid are lacking and the true rate of metal debris formation at mid-to long-term is unknown.…”