Bespoke vs Standard Instrumentation in TKR (SPHERE)

Randomised Control Trial of Patient Specific Instrumentation vs Standard Instrumentation of the GMK-Sphere (Global Medacta Knee) Total Knee Arthroplasty

Total knee replacements are operations that are offered to patients who have severe arthritis pain that is affecting daily activities that is no longer controlled with painkillers. The operation will replace the worn joints with metal implants and a plastic spacer. Total knee replacements are successful operations in the vast majority of patients. However, a small minority of patients are not entirely satisfied with the outcome of their knee replacement. Researchers are studying whether the precise positioning of the implant has an effect on the outcome.

This study will look at whether patient-specific instrumentation improves implant position and if it leads to improved patient function so that we know what to recommend in the future.

Study Overview

• Status: Completed
• Conditions: Knee Osteoarthritis
• Intervention / Treatment: Procedure: Conventional; Procedure: Patient specific instrumentation; Device: Patient specific instrumentation

• Study Type: Interventional
• Enrollment (Actual): 172
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Manchester, United Kingdom
    • Trafford General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients with osteoarthritis of the knee which is sufficiently symptomatic to require knee arthroplasty as assessed by their consultant orthopaedic surgeon

Exclusion Criteria:

• Patients with inflammatory arthropathy, patients requiring bone augmentation, patients with ligament incompetence or valgus deformity >5 degrees.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Conventional; Total knee replacement with conventional instrumentation	Procedure: Conventional; Total knee replacement with conventional instrumentation
Active Comparator: Patient specific instrumentation; Total knee replacement with patient specific instrumentation	Procedure: Patient specific instrumentation; Total knee replacement with patient specific instrumentation; Device: Patient specific instrumentation; Medacta GMK Sphere MyKnee Patient specific Instrumentation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline Gait Kinematics at 1-Year	Gait of patients will be analysed pre-operatively, six-weeks post-operatively, and 1-year post-operatively by 3D motion capture technology. The change measured over time at 1-year will be the primary outcome.	1 year post-operatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient Satisfaction (Pain/Hospital experience/functional ability/Surgery expectations)	Patient satisfaction will be reported using a scale on a questionnaire which asks six questions on how happy patients were with their hospital experience/level of pain/functional ability post-operatively. The questionnaire also asks whether their expectations were met. The two satisfaction questions are answered on a scale of 'Very Satisfied/Satisfied/Unsure/Dissatisfied' by ticking the appropriate box. The four questions based on patient expectation are scored on a scale of 'Excellent/Good/Unsure/Poor' by ticking the appropriate box.	1 year post-operatively
Oxford Knee Score (Patient reported outcome measure of pain and function)	A joint specific questionnaire which asks patients on the level of pain and function they believe to have in their affected knee (taking into consideration the past 4 weeks only). The questionnaire consists of 12 questions. Five of the questions are pain related, and seven are aimed at function. Each question has 5 options and is scored from 0-4, with 4 being the best and 0 being the worst pain/function. The best score is therefore 48 (no pain/good function), and the worst score is 0 (pain and poor function).	6 weeks post-operatively
Oxford Knee Score (Patient reported outcome measure of pain and function)	A joint specific questionnaire which asks patients on the level of pain and function they believe to have in their affected knee (taking into consideration the past 4 weeks only). The questionnaire consists of 12 questions. Five of the questions are pain related, and seven are aimed at function. Each question has 5 options and is scored from 0-4, with 4 being the best and 0 being the worst pain/function. The best score is therefore 48 (no pain/good function), and the worst score is 0 (pain and poor function).	1 year post-operatively
EuroQol-5 Dimensions (EQ-5D) (Patient reported outcome measure of patients' perception of their overall health)	A questionnaire on patients' perception of their overall health. The questionnaire focuses on generic health in 5 dimensions: Mobility, self-care, pain or discomfort, anxiety or depression and usual activities (including work, housework, leisure, family, and study). The questions are scored using an algorithm; the result of which relates to the health status of the patient. This score ranges between 0 (equivalent to death) to 1 (equivalent to full health). It also contains a visual analogue scale where patients have to choose on a scale of 0-100 how well they believe their general health to be on that particular day, where 0 is the worst health imaginable and 100 is the best health imaginable.	6 weeks post-operatively
Short Form-12 (SF-12) (Patient reported outcome measure of general quality of life)	A general Quality of Life score with 12 questions. It has mental and physical components which are scored from the same questions, using different algorithms. Each question is multiple choice, and the patient must tick one answer. Each answer corresponds to a standardised value, which is used in two algorithms to generate an overall score. One score is for the mental component and one is for the physical component. The physical standardized values are summed across all 12 items. 56.57706 is added to the sum to create the SF-12 physical score. 60.75781 is added to sum create the SF-12 mental score. Higher overall scores are better than lower scores.	6 weeks post-operatively
Short Form-12 (SF-12) (Patient reported outcome measure of general quality of life)	A general Quality of Life score with 12 questions. It has mental and physical components which are scored from the same questions, using different algorithms. Each question is multiple choice, and the patient must tick one answer. Each answer corresponds to a standardised value, which is used in two algorithms to generate an overall score. One score is for the mental component and one is for the physical component. The physical standardized values are summed across all 12 items. 56.57706 is added to the sum to create the SF-12 physical score. 60.75781 is added to sum create the SF-12 mental score. Higher overall scores are better than lower scores.	1 year post-operatively
EuroQol-5 Dimensions (EQ-5D) (Patient reported outcome measure of patients'	A questionnaire on patients' perception of their overall health. The questionnaire focuses on generic health in 5 dimensions: Mobility, self-care, pain or discomfort, anxiety or depression and usual activities (including work, housework, leisure, family, and study). The questions are scored using an algorithm; the result of which relates to the health status of the patient. This score ranges between 0 (equivalent to death) to 1 (equivalent to full health). It also contains a visual analogue scale where patients have to choose on a scale of 0-100 how well they believe their general health to be on that particular day, where 0 is the worst health imaginable and 100 is the best health imaginable.	1 year post-operatively
Knee range of motion	Knee range of motion in degrees will be assessed using a goniometer	6 weeks post-operatively
Knee range of motion	Knee range of motion in degrees will be assessed using a goniometer	1 year post-operatively

Collaborators and Investigators

• Sponsor: Manchester University NHS Foundation Trust
• Collaborators: University of Manchester
• Investigators: Principal Investigator: Leela Biant, University of Manchester

Study record dates

Study Major Dates

• Study Start (Actual): September 21, 2021
• Primary Completion (Actual): December 31, 2024
• Study Completion (Actual): December 31, 2024

Study Registration Dates

• First Submitted: October 11, 2022
• First Submitted That Met QC Criteria: October 11, 2022
• First Posted (Actual): October 14, 2022

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: January 28, 2025
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Keywords: Osteoarthritis; Gait; Knee; Stability; Functional Outcome; Total knee arthroplasty; Patient Specific Instrumentation
• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Arthritis; Joint Diseases; Rheumatic Diseases; Osteoarthritis
• Other Study ID Numbers: R04611

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Study protocol and participant facing documents can be shared to other researchers upon request to the research team. Requests can be emailed to MORE@manchester.ac.uk

Drug and device information, study documents

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