Differences in incidence rate and onset timing of undiagnosed finger symptom among shoulder surgeries related to complex regional pain syndrome

The purpose of this study was to clarify the difference in onset timing and incidence of undiagnosed finger symptom (UDFS) between various shoulder surgical procedures. In this study, UDFS symptoms included the following four symptoms in the fingers ; edema, limited range-of-motion, skin color changes, and abnormal sensations. UDFS cases were defined as those presenting with at least one UDFS. In result, the incidence rate of UDFS cases was 7.1% overall (58 / 816 shoulders), 7.4% (32 / 432) in arthroscopic rotator cuff repair (ARCR), 9.0% (11 / 122) in open rotator cuff repair (ORCR), 1.4% (2 / 145) in arthroscopic subacromial decompression (ASD), 13.2% (5 / 38) in open reduction and internal fixation (ORIF), 11.1% (3 / 27) in humeral head replacement, 4.8% (1 / 21) in anatomical total shoulder arthroplasty, and 12.9% (4 / 31) in reverse total shoulder arthroplasty cases. The Rate was significantly higher with ARCR compared to ASD (p < .01). About onset timing in weeks postoperatively, the ORIF group had a statistically earlier symptom onset than the Rotator cuff repair (ARCR + ORCR) group (2.4 weeks vs. 6.0 weeks, p < .01). When classifying the onset timing into before and after the removal of the abduction pillow, the ORIF group showed a statistically higher rate of onset before brace removal than the Rotator cuff repair groups (p < .01). Differences in UDFS among shoulder surgeries were demonstrated in this study.