Combined glenoid and humeral bone loss has been identified as an important factor in predicting recurrence after arthroscopic shoulder stabilisation. The “glenoid track” concept is proposed to predict recurrent instability by comparing the relative size of the glenoid to the humeral bone defect. The aim of this study was to investigate whether assessment of the glenoid track on a pre-operative MR arthrogram could be used to predict subsequent instability in a typical UK population. A retrospective study was undertaken of 175 primary arthroscopic stabilisation procedures of which 82% (n=143) were men. The median age was 26 years (IQR 22 to 32, range 16 to 77). The median follow-up was 76 months (range 21 to 125). A pre-operative MR arthrogram was used to determine if the shoulder was on-track or off-track. The endpoint of recurrent dislocation was examined. The prevalence of “off-track” bone loss in this group was 14.2% (n=25). There were 6 (24%) dislocations in the off-track group compared with 5 (3.33%) dislocations in the on-track group (RR 7.2, 95% CI 2.45 to 20.5, p=0.001). At 5 years, the cumulative redislocation rate was 26.1% in the off-track group compared with 8.7% in on-track group. The rate of any recurrent instability was 60% (n=15) v 18% (n=27) (RR 3.33, 95% CI 2.02 to 5.20, p<0.0001). Glenoid track (on v off) was not predicted by gender (p=0.411). In a typical UK population assessment of the glenoid track on an MR arthrogram can be used to risk stratify patients with shoulder instability.
Successful treatment of periprosthetic joint infection involves surgical intervention and identification of infecting organisms to enable targeted antibiotic therapy. Current guidelines recommend intra-operative culture sampling to include at least 4 tissue samples and for each sample to be taken with a separate instrument. We aimed to review current revision arthroplasty practice for Greater Glasgow, specifically comparing intra-operative sampling technique for infected revision cases with these guidelines. We reviewed the clinical notes of all patients undergoing lower limb revision arthroplasty procedures in Greater Glasgow Hospitals (WIG, GRI, SGH) from July 2013 to August 2014. Demographics of all cases were collected. For revision procedures performed for infection we recorded details of intraoperative samples taken (number, type and sampling technique) and time for samples to reach the laboratory. Results of microbiology cultures were reviewed. Two hundred and fifty five revision arthroplasty procedures (152 hips, 103 knees) were performed in the 12 month study period. Of these 57 (22%) were infected cases (28 hips, 29 knees). These cases were treated by 14 arthroplasty surgeons with a median number of 3 infected cases managed per surgeon (range 1–11). 58% of cases had the recommended number of tissue samples taken. The median number of microbiology samples collected was 4 (range 1–14). Most procedures (91%) had no documentation of whether separate instruments were used for sampling. Number of tissue samples taken (≥4, p=0.01), time to lab (<24 hours, p=0.03) were significantly associated with positive culture results. In Greater Glasgow, a large number of surgeons manage infected arthroplasty cases with variability in intra-operative sampling techniques. Sample collection adheres to guideline recommendations in 58% cases. Adhering to guideline standards increases the likelihood of positive tissue cultures. Implementation of a standardised approach to intra-operative sampling for infected cases may improve patient management.