Gait, Pain and Physical Activity After HTO

This study aims to investigate the relationship between pain, gait and activity intensity in HTO patients that are healed and have had their fixation plate removed.

Inclusion criteria

are: unilateral HTO with no concurrent procedure performed, fixation plate has since been removed, no subsequent operations performed on the lower limbs (hips to feet). Control participants will be recruited through local advertisements in and around the University of Winchester. Inclusion criteria for the control subjects are: no current pain in the lower limbs, no previous surgery on the lower limbs. Control subjects will also be age-matched to the HTO group.

Knee function and pain scores will first be assessed through the implementation of a Knee Osteoarthritis Outcome Score, a Visual Analogue Scale, and a further pain intensity scale. Once this has been done, resting heart rate (HR) and body mass index (BMI) will also be measured as part of the completion of a Physical Activity Readiness Questionnaire (PAR-Q). A G-Walk gait analysis sensor, which has been validated for use in clinical settings, will then be attached to participants in order to measure spatiotemporal gait parameters during testing.

Each participant will then conduct a series of four walking and four jogging test protocols, each lasting three minutes, on a flat treadmill. The intensity at which the participant must walk or jog during each test will be self-regulated and determined by a rating of perceived exertion (RPE) of 9, 11, 13 or 15 on a 6-20 Borg scale. All participants will be verbally anchored to the Borg scale before conducting the first walk/jog test. The order in which the tests are performed will be randomised in advance of each test session. Half way through each test (90 seconds), participants will be presented with a VAS and pain intensity scale to indicate the current level of pain they are experiencing in their knee. At this stage, they will also be asked to confirm that they are still maintaining the target RPE of that particular test. Once a test is finished, participants will complete another VAS and pain intensity scale and rest in a seated position until their heart rate returns to their pre-determined resting level before the next test commences. The leg for which healthy controls report pain levels will be chosen randomly prior to the test session.

Inclusion criteria

• Experimental group:

Previously undergone unilateral medial opening wedge high tibial osteotomy with no simultaneous procedures (other than arthroscopy), performed by one of 3 different surgeons

Plate since removed

No conversion to arthroplasty since the osteotomy

• Control group:

Age-matched to experimental group

Never previously undergone any form of lower limb surgery

Exclusion criteria

• Experimental group:

Undergone other procedures simultaneous to the osteotomy

Plate in-situ

• Control group:

Previously undergone lower limb surgery