Keywords:
Musculoskeletal joint, Musculoskeletal soft tissue, Ultrasound, Conventional radiography, Diagnostic procedure, Athletic injuries, Inflammation
Authors:
J. Murphy1, J. yusta-zato2, A. Patel3, A. M. Davies3, S. L. James3, C. McBryde3, R. Botchu3; 1Cork/IE, 2Manchester/UK, 3Birmingham/UK
DOI:
10.26044/ecr2019/C-1094
Conclusion
Pain post THA occurs in a small percentage of patients.
Lateral hip pain is reported to occur in approximately 4.4% of patients following THA6 and can be attributed to a variety of causes including gluteal tendinopathy,
trochanteric bursitis and trochanteric pelvic impingement.
When performing THA,
the femoral stem and acetabular cup must be positioned optimally to restore mechanical forces and range of motion.
It has been shown that hip abductor function is optimised by a slight increase in femoral offset and inferomedial cup position to restore the normal hip joint centre.1 Medializing the acetabular cup risks reducing global offset and in order to confer the biomechanical benefits of medializing the acetabular cup,
a compensatory,
equivalent increase in femoral offset is necessary at the risk of increased tension on the abductor muscles.1-3 Thus careful surgical planning is essential.
To our knowledge,
a study evaluating the correlation between ultrasound findings of gluteal tendinopathy and trochanteric bursitis and the femoral offset and abductor lever arm has not been previously reported.
A small study of 15 patients has shown the association between increased femoral offset and clinical evidence of trochanteric bursitis.4 Impingement distance,
as defined by Isaacson et al,
has also been hypothesised to contribute to trochanteric-pelvic impingement as a cause of lateral hip pain in patients post THA.5 Interestingly,
in this study,
there was a trend for FO and GO to be lower in patients with symptoms in a native hip and higher in patients with symptoms in a THA when compared to the normal asymptomatic hip,
however,
this was not statistically significant.
We also evaluated these parameters in patients with lateral hip pain in a native hip and again a statistically significant correlation was not found.
We sought to describe the normal range of FO,
GO,
TID and ALA in the normal healthy hip which may aid in the management of hip pain and arthroplasty.
There are some limitations to this study.
Ultrasound of the gluteal tendons and bursae can be subjective,
is operator-dependent and can be limited by patient factors.
In addition,
there are additional variables to consider in patients with unilateral THA and lateral hip pain in the contralateral native hip whereby the biomechanics of the native hip are inevitably affected by the contralateral THA.
This study demonstrates that there is no statistically significant relationship between these radiographic measurements and ultrasound findings of tendinopathy,
or subgluteal or trochanteric bursitis.
However,
it provides a range of measurements in the normal,
asymptomatic hip for FO,
GO,
TID and ALA for reference,
which may aid in the assessment and management of patients with lateral hip pain.