Plain English Summary
Background and study aims
The knee is the largest weight-bearing joint in the body. It is a complex joint where the shin bone (tibia) and thigh bone (femur) meet creating a “hinge”. The kneecap (patella) is a small, triangular shaped bone located in front of the knee joint. It is very important that the patella is in the correct position, as it plays a vital role in helping to bend (flexion) the knee by acting as a “pulley” for the thigh (quadriceps) muscle. Patellar mal-alignment, also known as patellofemoral pain is a common condition in which the patellar does not aligned properly. Normally, when the knee bends, the patellar moves in a small groove in the femur (femoral groove). When the patella is not lined up with this groove, it can travel more to the side, making it rub against the femur. This causes the knee to become overloaded with pressure causing pain when bending the knee. A common treatment for patellar mal-alignment is taping the knee to support the patella (McConnell taping technique). This works by applying the tape to the skin to reposition the patella relative to the femur when the knee is bent up to 30° (30° flexion). It has been found that many patients experience a reduction in pain after this taping is applied, however more research is needed to find out if the tape is actually managing to realign the patella. The aim of this study is to find out whether the McConnell taping technique can realign the position of the patella in an MRI scanner and with a calliper, and whether this will lead to reduced pain during squat activities.
Who can participate?
Adults with pain at the front and center of the knee with patellar mal-alignment.
What does the study involve?
All participants begin the study by having measurements taken of their leg in order to look at the position of the patella when the knee is bent at 30°, using MRI scanning and a custom built calliper (device for measuring distance). They are also asked to complete squatting exercises so that their levels of pain can be measured. These measurements are then repeated in order to ensure that the measurements are valid. Participants are then randomly allocated to one of two groups. Those in the first group have their knee taped using the McConnell taping technique, to support the patella in the correct position. Those in the second group have placebo (dummy) taping applied, which is not designed to have any effect on their patella positioning. For all participants, the tape is worn for about 20 minutes so the measurements of patella position and pain can be repeated. Those in the corrective taping group will then have the placebo taping applied, and those in the placebo group will have the corrective taping applied.
What are the possible benefits and risks of participating?
Participants may benefit from a reduction in pain from the taping. This could help to find better treatments for that individual in future. There are no notable risks of taking part, although participants may feel pain when they are completing the squatting exercises.
Where is the study run from?
London Sports Orthopaedics (UK)
When is the study starting and how long is it expected to run for?
January 2016 to September 2016
Who is funding the study?
1. Buckinghamshire New University (UK)
2. Brunel University London (UK)
Who is the main contact?
Mr Kevin Campbell-Karn
Effects of taping on MRI and a novel caliper measuring patellar mal-alignment and subjective perception of pain in patients with patellofemoral pain (PFP)
1. There will be a reduction in pain during squat activities when patellar taping is applied and when placebo taping is applied when compared to baseline
2. MRI will not display any significant differences in patellar positioning following patellar taping and placebo
3. The MRI patellar positioning will correlate with the patellofemoral calliper data
4. The patellofemoral calliper will have good agreement with the MRI equivalent data
5. The patellofemoral caliper will provide good intratester reliability
6. The patellofemoral caliper will not display any significant differences in patellar positioning following taping and placebo
Research Ethics Committee of the College of Health and Life Sciences,30/01/2015, ref: RE13-14
Single-centre randomised controlled trial
Primary study design
Secondary study design
Randomised cross over trial
Quality of life
Patient information sheet
All participants will have baseline measures taken at the start of the visit. These include: MRI of the knee in a fixed 30 degrees of flexion position, VAS measured during a squat activity and measurements taken using the patellofemoral calliper for the location of the knee cap. All participants are then assessed again in order to ensure that no changes occur by chance. Participants are then randomly allocated to one of two groups:
Intervention group: Participants will have McConnell taping applied in accordance with the process to alleviate mal-alignment and will have an MRI, a patellofemoral caliper measurement and a squatting movement to assess pain.
Placebo group: Participants will have sham tape applied to the front of the knee without any correction to the position of the knee cap, again participants will have an MRI, a patellofemoral caliper measurement and a squatting movement to assess pain.
Primary outcome measures
1. Bisect offset, patellar overhang, congruence angle, sulcus angle, patellar shift, and equivalent position measurements are measured using MRI extracted data tested before and after each intervention
2. Pain measured using visual analogue scale (VAS) before and after each intervention
3. Relative postions of the patella and femur are measured using patellofemoral caliper measurements tested before and after each intervention
Secondary outcome measures
1. Comparisons between the MRI extracted data and the patellofemoral caliper measurements compared after the trials are all completed using MRI data and the mean scores from the caliper
2. Changes in VAS sores measured immediately after interventions correlating to any changes in MRI and caliper measurements
Overall trial start date
Overall trial end date
Participant inclusion criteria
1. Aged 18 years or over
2. Symptomatic with anterior knee pain
3. Confirmed as having patellar malalignment by an orthopaedic consultant via X-ray
Target number of participants
Participant exclusion criteria
1. Vulnerable adults or those unable to make decisions for themselves
2. Under 18 years of age
3. Anyone with metal or other implants containing metals such as pacemakers
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
London Sports Orthopaedics
31 Old Broad Street
Buckinghamshire New University
Funding Body Type
Funding Body Subtype
Brunel University London
Funding Body Type
private sector organisation
Funding Body Subtype
Results and Publications
Publication and dissemination plan
This study is intended to be published in peer reviewed scientific journals. The data will also be shared with the International Patellofemoral Pain research retreat and will be presented at international conferences to the scientific community.
Intention to publish date
Participant level data
Not expected to be available
Results - basic reporting