The metal backed glenoid component in total shoulder replacement (TSR) has been associated with high revision rates and some authors have suspended the use of this implant.

The aim of this study was to evaluate the medium to long-term outcome of the metal backed glenoid component in rheumatoid patients.

Thirty-nine patients (46 shoulders) with a mean age of 55 years (35–86 years) received a TSR with a screw fixed porous coated metal-back glenoid. Ten were lost or died before 8 years follow-up, of which none were revised. Twenty-nine patients (36 shoulders) were followed up for a mean of 132 months (96–168 months). A Constant score was measured preoperatively and annually from time of surgery, and independently at last follow-up. Radiographs were assessed for lucency, loosening and superior subluxation of the humeral head.

The Constant score improved by 12.9 points (p=< 0.001). Implant survivorship at 10 years was 89%. Five were revised: 3 for pain secondary to superior subluxation, one for infection and one for aseptic loosing. All patients with lucent zones around the glenoid (four) had superior subluxation of the humeral head two to four years prior to their development. Survival rate however at 10 years was reduced, if judged by the development of superior subluxation on radiographs (33%).

The uncemented glenoid performs well in the rheumatoid shoulder, giving pain relief and improved functional outcome. The survivorship is comparable to previously reported studies.

To identify the incidence and timing of superior subluxation following total shoulder replacement (TSR) and any associated change in pain, activities of daily living and ranges of movement. Forty-six TSR in rheumatoid patients with more than 5years follow-up were identified from a prospectively compiled database held by the senior author (ANS). Modified Constant scores (excluding the power component) were measured and recorded prospectively every 2years. Pre-operative and complete follow-up scores were available for 35 joints (27 patients). A Mann-Whitney U test was used to compare patients with subluxation and those without, with regard to the changes in the components of the Constant score at last follow-up compared with the pre-operative score. Superior subluxation of the humeral head was defined as when the lower third of the humeral head had migrated level or superior to the midpoint of the glenoid component as measured on the AP radiograph. An independent observer reviewed AP radiographs, taken at each 2 yearly review, at random with identity hidden and in no particular date order. Twenty-three patients developed superior subluxation since surgery, of which 87% occurred after 5years. Of the 35 joints with both clinical and radiological follow-up, 16 had evidence of subluxation. There was no statistically significant difference between the changes in the activities of daily living (Mann-Whitney U=106, p=0.1) and range of movement (U=140, p=0.7) components of the Constant score. However, patients without subluxation had a greater improvement in their pain scores (U=80, p=0.02). Approximately half of rheumatoid patients with TSR will demonstrate radiological changes of superior subluxation, in the majority after 5 years. This change is not associated with deterioration in activities of daily living or ranges of movement. However, pain relief persists irrespective of subluxation but is greater in those without subluxation.

To identify the incidence and timing of superior subluxation following total shoulder replacement (TSR) and any associated change in pain, activities of daily living and ranges of movement. Forty-six TSR in rheumatoid patients with more than 5years follow-up were identified from a prospectively compiled database held by the senior author (ANS). Modified Constant scores (excluding the power component) were measured and recorded prospectively every 2years. Pre-operative and complete follow-up scores were available for 35 joints (27 patients). A Mann-Whitney U test was used to compare patients with subluxation and those without, with regard to the changes in the components of the Constant score at last follow-up compared with the pre-operative score. Superior subluxation of the humeral head was defined as when the lower third of the humeral head had migrated level or superior to the midpoint of the glenoid component as measured on the AP radiograph. An independent observer reviewed AP radiographs, taken at each 2 yearly review, at random with identity hidden and in no particular date order. Twenty-three patients developed superior subluxation since surgery, of which 87% occurred after 5years. Of the 35 joints with both clinical and radiological follow-up, 16 had evidence of subluxation. There was no statistically significant difference between the changes in the activities of daily living (Mann-Whitney U=106, p=0.1) and range of movement (U=140, p=0.7) components of the Constant score. However, patients without subluxation had a greater improvement in their pain scores (U=80, p=0.02). Approximately half of rheumatoid patients with TSR will demonstrate radiological changes of superior subluxation, in the majority after 5 years. This change is not associated with deterioration in activities of daily living or ranges of movement. However, pain relief persists irrespective of subluxation but is better maintained in those without subluxation.