Recovery Trajectories After Total Knee Arthroplasty

Recovery Trajectories After Cruciate Retaining And Posterior Stabilized Total Knee Arthroplasty

This prospective cohort study aimed to compare recovery trajectories following cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) using rehabilitation-centered patient-reported outcome measures (PROMs). Forty patients undergoing primary unilateral TKA were evaluated preoperatively and at 3 and 6 months postoperatively. Outcomes included pain intensity, functional status, kinesiophobia, health-related quality of life, and joint awareness assessed using validated PROMs including the Visual Analog Scale (VAS), WOMAC, Tampa Scale for Kinesiophobia (TSK), SF-36, and Forgotten Joint Score-12 (FJS-12). The study investigated whether posterior cruciate ligament management influences early postoperative recovery trajectories after TKA.

Study Overview

• Status: Completed
• Conditions: Patient Reported Outcome Measurements; Cruciate Ligament Reconstruction; Total Knee Anthroplasty
• Intervention / Treatment: Other: Posterior-Stabilized Total Knee Arthroplasty; Other: Cruciate-Retaining Total Knee Arthroplasty

Detailed Description

Total knee arthroplasty (TKA) is an effective surgical intervention for patients with advanced knee osteoarthritis who experience persistent pain and functional limitations despite conservative treatment. Among contemporary implant designs, cruciate-retaining (CR) and posterior-stabilized (PS) prostheses are the most widely used approaches. CR implants preserve the posterior cruciate ligament (PCL) to maintain more physiological knee kinematics, whereas PS implants substitute PCL function through a post-cam mechanism. Although both designs have demonstrated successful clinical outcomes, evidence regarding their comparative influence on postoperative recovery remains inconclusive.

In recent years, postoperative evaluation after TKA has increasingly emphasized rehabilitation-centered patient-reported outcome measures (PROMs) rather than solely clinician-based assessments. Parameters such as pain, functional status, quality of life, kinesiophobia, and joint awareness provide a more comprehensive understanding of patient recovery and adaptation after surgery. However, studies directly comparing CR and PS TKA from this multidimensional rehabilitation perspective remain limited.

This single-center prospective cohort study was conducted at the Department of Orthopedics and Traumatology, Ondokuz Mayıs University Health Application and Research Center. Patients aged 50 years or older undergoing primary unilateral TKA were included. Participants were allocated to CR or PS groups according to intraoperative surgical decision-making based on posterior cruciate ligament integrity, soft-tissue balance, and routine surgical practice. Standardized perioperative management and postoperative rehabilitation protocols were applied to all participants.

Pain intensity was assessed using the Visual Analog Scale (VAS), functional status with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), kinesiophobia with the Tampa Scale for Kinesiophobia (TSK), and health-related quality of life with the Short Form-36 Health Survey (SF-36). Joint awareness was evaluated postoperatively using the Forgotten Joint Score-12 (FJS-12). Assessments were performed preoperatively and repeated at 3 and 6 months after surgery.

The primary objective of the study was to compare longitudinal recovery trajectories between CR and PS TKA designs across rehabilitation-related PROMs. The study further aimed to determine whether posterior cruciate ligament management influences pain reduction, functional recovery, psychosocial adaptation, and joint awareness during the early postoperative period.

• Study Type: Observational
• Enrollment (Actual): 40

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Atakum
    • Samsun, Atakum, Turkey (Türkiye), 55270
      • Ondokuz Mayis University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

The study population consisted of patients aged between 50 years and 65 years who were scheduled to undergo primary unilateral total knee arthroplasty at a single orthopedic center. All participants were Turkish-speaking, fully oriented, and capable of completing patient-reported outcome measures. The cohort included individuals who received surgery under standardized perioperative and postoperative care protocols. Patients with revision arthroplasty, neurological or neuromuscular disorders affecting gait, cognitive impairment, psychiatric disease, or major perioperative complications were not included in the study population.

Description

Inclusion Criteria:

• Patients scheduled for primary unilateral total knee arthroplasty (TKA).
• Ability to read and understand Turkish.
• Full orientation in person, place, and time.
• Voluntary participation with informed consent.
• Surgery performed at the same institution under standardized perioperative and postoperative care protocols.

Exclusion Criteria:

• Revision total knee arthroplasty.
• Presence of neuromuscular or neurological disorders affecting gait (e.g., stroke, Parkinson disease, myopathies).
• Cognitive impairment or diagnosed psychiatric disorders that may interfere with questionnaire completion or participation.
• Perioperative complications such as excessive bleeding, infection, prosthesis dislocation, or deep venous thrombosis.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Posterior-stabilized Group; Participants in the posterior-stabilized (PS) group underwent primary unilateral total knee arthroplasty using a posterior cruciate ligament-substituting implant design with a post-cam stabilization mechanism. Implant selection was determined intraoperatively according to posterior cruciate ligament condition, soft-tissue balancing requirements, and standard surgical practice. All participants received standardized perioperative care and postoperative rehabilitation. Recovery trajectories were assessed using validated patient-reported outcome measures evaluating pain, function, kinesiophobia, quality of life, and joint awareness before surgery and at 3 and 6 months postoperatively.	Other: Posterior-Stabilized Total Knee Arthroplasty; Primary unilateral total knee arthroplasty performed using a posterior-stabilized implant design incorporating a post-cam mechanism to substitute posterior cruciate ligament (PCL) function. Implant selection was determined intraoperatively according to ligament condition and soft-tissue balancing requirements. All participants received standardized perioperative care and postoperative rehabilitation.
Cruciate-Retaining Group; Participants in the cruciate-retaining (CR) group underwent primary unilateral total knee arthroplasty using a posterior cruciate ligament-preserving implant design. Implant selection was determined intraoperatively based on posterior cruciate ligament integrity, soft-tissue balance, and routine surgical assessment. Patients received standardized perioperative management and postoperative rehabilitation protocols. Recovery outcomes were evaluated using patient-reported outcome measures including pain intensity, functional status, kinesiophobia, health-related quality of life, and joint awareness at preoperative, 3-month, and 6-month follow-up assessments.	Other: Cruciate-Retaining Total Knee Arthroplasty; Primary unilateral total knee arthroplasty performed using a cruciate-retaining implant design in which the posterior cruciate ligament (PCL) was preserved. Implant selection was based on intraoperative assessment of ligament integrity and soft-tissue balance. Standardized perioperative management and postoperative rehabilitation protocols were applied to all participants.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Pain Intensity Assessed by Visual Analog Scale (VAS)	The primary outcome measure is pain intensity evaluated using the 10-cm Visual Analog Scale (VAS). Patients indicate their perceived pain level on a continuous scale ranging from 0 (no pain) to 10 (worst imaginable pain). Higher scores indicate greater pain severity. The VAS is a widely validated patient-reported outcome measure used to quantify subjective pain intensity in musculoskeletal and postoperative populations.	Baseline
Functional Status Assessed by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)	Functional status is evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), which assesses pain, stiffness, and physical function. The questionnaire consists of multiple items scored on a Likert scale. Higher total and subscale scores indicate worse symptoms and greater functional impairment. WOMAC is a validated disease-specific outcome measure commonly used in lower extremity musculoskeletal conditions.	Baseline
Fear of Movement Assessed by Tampa Scale for Kinesiophobia (TSK)	Fear of movement and (re)injury is measured using the Tampa Scale for Kinesiophobia (TSK). The scale evaluates fear-related beliefs about physical activity and movement. It consists of multiple items rated on a Likert scale, with higher total scores indicating greater levels of kinesiophobia. The TSK is a validated tool widely used in musculoskeletal and postoperative rehabilitation populations.	Baseline
Health-Related Quality of Life Assessed by Short Form-36 (SF-36)	Health-related quality of life is assessed using the Short Form-36 (SF-36) questionnaire, which includes eight domains: physical functioning, role limitations due to physical health, bodily pain, general health perceptions, vitality, social functioning, role limitations due to emotional problems, and mental health. Each domain is scored from 0 to 100, with higher scores indicating better perceived health status. SF-36 is a generic, validated quality-of-life instrument.	Baseline
Postoperative Joint Awareness Assessed by Forgotten Joint Score-12 (FJS-12)	Postoperative joint awareness is evaluated using the Forgotten Joint Score-12 (FJS-12), a joint-specific patient-reported outcome measure designed to assess the ability of patients to "forget" the presence of an artificial or affected joint during daily activities. The score is transformed to a 0-100 scale, where higher scores indicate lower joint awareness and better functional integration of the joint in daily life. The FJS-12 has a low ceiling effect and high sensitivity in detecting subtle differences in joint perception.	Baseline

Collaborators and Investigators

• Sponsor: Ondokuz Mayıs University

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2025
• Primary Completion (Actual): July 1, 2025
• Study Completion (Actual): July 1, 2025

Study Registration Dates

• First Submitted: May 12, 2026
• First Submitted That Met QC Criteria: May 12, 2026
• First Posted (Actual): May 19, 2026

Study Record Updates

• Last Update Posted (Actual): May 19, 2026
• Last Update Submitted That Met QC Criteria: May 12, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: total knee arthroplasty; posterior-stabilized; cruciate-retaining; patient-reported outcome measures; forgotten joint score
• Other Study ID Numbers: OMU2025/182

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No