The Pain Paradox of Borderline Personality and Total Knee Arthroplasty (TKA): Recruiting Borderline Personality Organization to Predict the One-Year Postoperative Outcome.

Background: TKA is a common treatment for arthropathies of the knee; however, its results are compromised by psychosocial equivalents of pain: prior research suggests persistent pain and dysfunction after TKA not only to be linked to psychological symptoms such as depression or anxiety but also to psychodynamic determinants of borderline personality, namely borderline personality organization. Osteoarthritis (OA) and Rheumatoid arthritis (RA), the main indications for TKA, are themselves linked to personality factors and disorders, e.g. borderline. The present study investigates the influence of borderline personality organization (BPO) on the outcomes of TKA one year postoperatively.

Methods: We studied 144 patients scheduled for primary TKA before and after the operation using the IPO-16 and the WOMAC for the assessment of knee pain and function.

Results: Non-parametric correlations were found between primitive defenses and knee-pain, not function. Linear regression showed prediction of knee pain and knee function by the preoperative WOMAC scores (p<0.01), whereas there was additional prediction of knee-pain by gender (p=0.03) and primitive defenses (p=0.04).

Discussion: The results suggest a psychodynamic mechanism of maladaptation after TKA apparently representing the bodily manifestations of fundamental psychic defenses.