Predictors of Improved Early Clinical Outcomes After Elective Implant Removal

Abstract

Objectives: To determine preoperative factors predictive of improvement in pain and function after elective implant removal. We hypothesized that patients undergoing orthopaedic implant removal to relieve pain would have significant improvements in both pain and function.

Design: Prospective cohort study.

Setting: Level I Trauma Center.

Patients/Participants: One hundred eighty-nine patients were enrolled after consenting for orthopaedic implant removal to address residual pain. One hundred sixty-three were available for 3-month follow-up.

Main Outcome Measurement: Preoperative and postoperative outcome measures including Patient Reported Outcomes Measurement Information System (PROMIS) scores were compared. Preoperative scores, surgeon prediction of pain improvement, and palpable implants were analyzed as predictors of outcomes.

Results: Median PROMIS physical function and pain interference scores and visual analogue scale significantly improved by 6, 8, and 2 points, respectively (P < 0.001 for all). Worse preinjury scores predicted improvement in respective postoperative outcomes (P < 0.001 for all). Surgeon prediction of improvement was associated with improved PROMIS pain interference (P = 0.005), patient subjective assessment of pain improvement (P = 0.03), and subjective percent of pain remaining at 3 months (P = 0.02). Implant superficial palpability was not predictive for any postoperative outcomes.

Conclusions: Although the primary indication for implant removal in this population was pain relief, many patients also had a clinically relevant improvement in physical function. In addition, patients who start with worse global indices of pain and function are more likely to improve after implant removal. This suggests that implant-related pain directly contributes to global dysfunction.