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Risk Factors and Mechanisms for Persistent Postsurgical Pain After Total Knee Replacement (PPP-TKA)

This study is currently recruiting participants. (see Contacts and Locations)
Verified June 2016 by Rush University Medical Center
Information provided by (Responsible Party):
Asokumar Buvanendran, Rush University Medical Center Identifier:
First received: March 18, 2011
Last updated: June 16, 2016
Last verified: June 2016

Osteoarthritis (OA) is the single most common cause of disability in mid and late life. About 27 million people in the United States suffer from this incurable process and 10 million have OA of the knee. Total knee replacement (TKR) is a reliable treatment option for patients disabled by knee OA who have failed non-operative treatment; 58% of these surgeries are performed on patients 65 years or older. Despite the overall success of TKR in most cases, persistent postsurgical pain (PPP) of the operated knee remains a common and often difficult to treat postoperative outcome affecting 13-20% of all patients at 6 months post-TKR, which amounts to 65,000-100,000 patients/year in the USA. Important secondary outcomes of PPP are restricted physical mobility and poor quality of life, especially in older patients.

Recent findings spanning the pre-, intra- and postoperative periods suggest that the development of PPP after TKR is a multi-factorial process, comprised of both neurophysiologic and psychosocial factors. Likely determinates include preoperative thermal pain sensitivity, anxiety, pain catastrophizing; and postoperative area of secondary mechanical hyperalgesia or hypoalgesia (numbness). There is already agreement that the intensity of early (acute) postoperative pain is one of the factors predicting PPP. To date, most studies have examined the role of risk factors in isolation and/or within a single domain, and no prospective study has comprehensively evaluated the interaction of neurophysiologic and psychosocial variables in the evolution of PPP following TKR. The lack of information regarding how neurophysiologic pathways and patient cognitive/affective states interact over time following otherwise successful TKR has greatly undermined the understanding of PPP after TKR.

The proposed project is a single-site, prospective study of 300 OA patients aged 18-85 yrs undergoing primary TKR. The study is designed to identify factors from the pre-, intra- and postoperative phases of TKR that contribute to PPP at 6 months. Specific risk factors were selected because they are potentially modifiable, and therefore may be amenable to intervention. Patients will be assessed from pre-surgery to 6 months post surgery. The proposed multi-factorial and prospective approach to investigating risk factors is a vital next step towards understanding the complex phenomenon of PPP.

Persistent Postsurgical Pain

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Prospective
Official Title: Risk Factors and Mechanisms for Persistent Postsurgical Pain After Total Knee Replacement

Resource links provided by NLM:

Further study details as provided by Rush University Medical Center:

Primary Outcome Measures:
  • PPP [ Time Frame: 6 months and 3 months postoperatively ]
    PPP for this study will be defined as "pain in the operated knee at six months after TKR, with other causes of pain excluded and reported intensity on 0-10 NRS scale of ≥4".

Biospecimen Retention:   Samples With DNA

Estimated Enrollment: 300
Study Start Date: March 2011
Estimated Study Completion Date: July 2017
Estimated Primary Completion Date: March 2017 (Final data collection date for primary outcome measure)
Study Subjects with PPP at followup
Subjects without PPP at followup

Detailed Description:

Overall Strategy: The primary aim of this application is to investigate relationships of risk factors to the development of persistent postoperative pain (PPP) at 6 mo following TKR, through independently predictive and mediated models.

These risk factors are preoperative thermal pain sensitivity, pain anxiety and catastrophizing; postoperative area of secondary mechanical hyperalgesia or hypoalgesia (numbness) and pain intensity. PPP for this study will be defined as "pain in the operated knee at six months after TKR, with other causes of pain excluded and reported intensity on 0-10 Numerical Response Scale (NRS) scale of ≥4". The study will also evaluate the relationship of PPP incidence with the severity of functional impairment. This is a single-site prospective clinical investigation of 300 consented OA patients undergoing primary, unilateral TKR.


Ages Eligible for Study:   18 Years to 85 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Osteoarthritis patients at the RUSH university medical center undergoing primary, unilateral TKR

Inclusion Criteria:

  • undergoing standard tricompartmental TKR;
  • 18 to 85 yrs of age;
  • patient has a diagnosis of osteoarthritis
  • knee to be replaced is the primary source of patient's pain;
  • patient agrees to preoperative and follow-up visits and to comply with the assessment tests;
  • patient consents to standard anesthetic and analgesic protocol, with medical care as deemed necessary by the anesthesiologist, and has no contraindications.

Exclusion Criteria:

  • chronic opioid use ≥ 10 mg/day of morphine equivalents within one wk prior to the surgery, and duration of use > 4 wks;
  • history of opioid abuse;
  • inability to understand and communicate with the investigators to complete the study related questionnaires
  • patient currently enrolled in another study;
  • patient is planning to undergo another elective joint replacement procedure during the 6-mo period of participation;
  • any co-morbidity which results in severe systemic disease limiting function {as defined by the American Society of Anesthesiology (ASA) physical status classification > 3}
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01320150

Contact: Asokumar Buvanendran, MD 312-942-3685
Contact: Mario Moric 312-942-2806

United States, Illinois
Rush University Medical Center Recruiting
Chicago, Illinois, United States, 60612
Contact: Asokumar Buvanendran, MD    312-942-3685   
Contact: Mahendra Shah, MD    312-942-1982   
Principal Investigator: Asokumar Buvanendran, MD         
Sub-Investigator: Craig Della Valle, MD         
Sponsors and Collaborators
Rush University Medical Center
Principal Investigator: Asokumar Buvanendran, MD Rush University Medical Center
  More Information

Responsible Party: Asokumar Buvanendran, Attending Physician, Rush University Medical Center Identifier: NCT01320150     History of Changes
Other Study ID Numbers: WS735224
Study First Received: March 18, 2011
Last Updated: June 16, 2016

Keywords provided by Rush University Medical Center:
persistent postsurgical pain (PPP) processed this record on April 26, 2017