Skip to main content
OpenTrials
Enrolling by Invitation

NCT Number: NCT07122323

Robotic Arm-assisted THA Vs. Conventional THA in Legg-Calvé-Perthes Disease

Flat hip, also called Legg-Calvé-Perthes disease, is clinically characterized by flattened femoral head, shortened femoral neck, and a center of rotation of the femoral head lower than the apex of the greater trochanter. Joint replacement is difficult, with high intraoperative and postoperative complications. Especially, issues such as unequal limb length, postoperative dislocation, postoperative neurological damage, and prosthesis impact have always plagued clinical practice.

The robotic arm-assisted joint replacement technology has been developed and clinically applied for over 10 years, but it was not until the past 3 years that it began to be widely implemented worldwide. Existing research data indicates that robotic arm-assisted joint replacement technology can significantly improve the placement of prostheses and lower limb force lines in patients, and improve their short-term clinical prognosis. However, its application in complex hips, such as flat hip, is limited. More relevant literature is needed to further enrich people's understanding of this technology. In theory, robot assisted technology can solve many challenges faced in flat hip replacement.

Enrolling by Invitation

Interested in participating?

Request Info

Key information

Age range

18 year–80 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Second Affiliated Hospital of Zhejiang University School of Medicine

Hangzhou, Zhejiang, 310009, China

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • patients with Legg-Calvé-Perthes disease and accept total hip replacement in our center

Exclusion criteria

  • infection, cannot complete follow-up

Treatment and study plan

robotic arm-assisted total hip replacement

Procedure

using robotic total hip replacement in patients with Legg-Calvé-Perthes disease

conventional total hip replacement

Procedure

applying conventional total hip replacement in patients with Legg-Calvé-Perthes disease

Primary outcomes

  1. inclination angle

    Time frame: 2 days after surgery

    The inclination angle in total hip replacement (THR), also called the abduction angle , refers to the angle at which the acetabular cup component is tilted relative to the horizontal plane when viewed on an anteroposterior (AP) pelvic X-ray.

  2. anteversion angle

    Time frame: 2 days after surgery

    The anteversion angle in total hip replacement (THR) refers to the forward tilt (rotation) of the acetabular cup component around its vertical axis. It determines whether the cup's opening faces more forward or backward relative to the pelvis.

  3. Hospital for Special Surgery Score score (HSS score)

    Time frame: before the surgery, 1 week after surgery, 1 month after surgery, 6 months after surgery, 1 year after surgery

    The maximum values is 100, and the minimum value is 0. Higher scores means a better outcome.

Secondary outcomes

  1. operation duration

    Time frame: during the operation

    The operation duration (also called operative time or surgical time ) refers to the total time taken to complete a surgical procedure.

  2. blood loss

    Time frame: during the operation

    The amount of blood loss during the surgery.

  3. Visual Analogue Scale score (VAS score)

    Time frame: before the surgery, 1 week after surgery, 1 month after surgery, 6 months after surgery, 1 year after surgery

    The maximum value is 10, and the minimum value is 0. Lower score means a better outcome.

Sponsors and collaborators

Lead sponsor

Second Affiliated Hospital, School of Medicine, Zhejiang University

Other

Registry information

Official study title

Comparison of Robotic Arm-assisted THA and Conventional Manual THA in Patients With Legg-Calvé-Perthes Disease: a Prospective Cohort Study

Important dates

Study start
2025
Primary completion
2027
Study completion
2027
First posted
Aug 14, 2025
Registry last updated
Aug 14, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Published trials that share one or more normalized conditions with this study.