Minimising Limb-length inequality following total hip replacement.
Research type
Research Study
Full title
Minimising Limb-length inequality following total hip replacement; a proof of concept study to develop a device-assisted intraoperative assessment technique.
IRAS ID
147512
Contact name
Daniel Skinner
Contact email
Sponsor organisation
Research Governance Manager, R&I Department
Duration of Study in the UK
1 years, 0 months, 1 days
Research summary
Unequal leg lengths after total hip replacement (THR) can lead to complications including hip dislocation, nerve damage and back pain and is now one of the top five reasons for litigation against surgeons in the UK. There are many ways of assessing leg length during hip replacement but none of these give perfect results. The most common method is the shuck test which is used to assess the tension of the muscles around the new hip by pulling on the leg to see how far the hip displaces. If the muscles are too tight it will not displace enough, if the muscles are too slack the hip will dislocate. Currently the test is subjective and decisions are made using the surgeon’s experience alone. This study aims to develop a device to measure the displacement. It consists of three studies;
Device development 1- displacement distance.
At the end of the operation when the hip is in position the shuck test will be performed with a trial head that is marked with measurement rings. The assistant will record how many rings are exposed. This will be repeated on 30 patients.
Device development 2 - displacement force.
After the optimal amount of distraction has been established in study 1, the force required to generate this will be calculated by distracting the head to the appropriate number of rings and using the device to record the amount of force required. This will be repeated in 150 patients and an average force calculated.
Device testing.
In a final group, at the end of an operation when the correct size implant is in position, the device will be used with the pre-calculated values above to check agreement with the experienced surgeon’s clinical decision.REC name
Yorkshire & The Humber - Sheffield Research Ethics Committee
REC reference
15/YH/0301
Date of REC Opinion
21 Aug 2015
REC opinion
Further Information Favourable Opinion