Long-Term Outcomes of Femoral Derotation Osteotomy for Individuals With Cerebral Palsy

NCT ID: NCT03444116

Last Updated: 2021-02-10

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 62 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2017-09-12
• Study Completion Date: 2019-11-15

Brief Summary

Excessive anteversion is commonly observed in the cerebral palsy (CP) population. This can be treated by an orthopedic surgery, called femoral derotation osteotomy (FDO), to de-rotate the femur. It is a vital aspect of patient care to understand if the effects of an FDO are maintained long-term. The results of this study will have direct clinical impact by equipping providers with the necessary information to counsel families by providing families the information needed to make the most informed decision possible about this aspect of their child's healthcare.

Detailed Description

Excessive anteversion is commonly observed in the CP population. If individuals do not internally rotate their femurs as a compensation for this bony torsion, excessive anteversion decreases the coronal plane moment arm of the hip abductors-a phenomenon often called lever arm dysfunction. Considering that adequate hip abductor strength is a crucial factor for normal walking and many other functional activities, the compensatory mechanism theory hypothesizes that individuals with excessive anteversion will internally rotate their hips to restore the coronal plane moment arms. Excessive internal hip rotation (IHR) is observed in the gait of approximately 50% of individuals with CP. It has been postulated, though, that while IHR may restore hip abductor function, it is cosmetically unappealing and may lead to trips and falls. Therefore, FDOs are considered the standard treatment for correcting excessive anteversion and IHR in individuals with CP. Notably, it is one of the top two orthopedic surgeries performed at Gillette Children's Specialty Healthcare. Among the ~4000 individuals with CP who have been seen in the gait lab, almost 1350 individuals (>2200 limbs) have undergone at least one FDO.

Short-term (~12 months postoperative) improvements of transverse plane hip rotation during gait range from only 33% to 94%. Despite FDO's widespread use, long-term outcomes of the procedure have only begun to be studied, with our 2016 study the only one that included a control group. Without a control group, the natural history of bony remodeling or gait adaptations is unknown. However, our prior study is limited by two main factors, 1) all data were extracted from our database retrospectively, so the potential for a large bias exists since outcomes reflect only patients with clinically-initiated gait visits, and 2) outcomes of hip abductor function were only measured by hip rotation (or hip abductor moment during gait, which is only available for individuals who can walk without assistive devices), so the true ability of the hip abductors to generate moment has not been tested. Furthermore, the vast majority of individuals were <18 years old at their "long-term" visit (~5 years after their preoperative gait visit), which precedes the reported gait or functional decline more commonly occurring in one's 20s and beyond.

Counseling families on the long-term outcomes after an FDO is currently not possible and is necessary for families and health-care providers to make informed decisions. It remains unclear whether individuals who receive an FDO experience long-term beneficial effects on function, activity, and comfort as compared to those who receive other or no treatment for their excessive anteversion and/or IHR.

Briefly, anteversion as measured by the trochanteric prominence angle test (TPAT) is the most common method used by clinicians to determine if an FDO is warranted, in addition to anteversion being an important predictor of predicted short-term outcomes after an FDO23. However, data from our lab suggests that there is 10-15° of measurement error associated with this method. As such, our secondary purpose was to compare anteversion as measured by the TPAT to that of a radiographical gold standard, EOS. EOS delivers 4-30 times less radiation to the gonads and lower extremities compared to computed tomography (CT)24, making it very suitable for research purposes. Additionally, accuracy of quantifying femoral anteversion is not compromised versus the current gold standard, CT, with a mean difference of ~3° reported.

Conditions

Cerebral Palsy; Femoral Derotation Osteotomy; Outcomes

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: OTHER

Study Groups

Cases (+FDO)

Patients who underwent an FDO

Motion Analysis

Intervention Type: DIAGNOSTIC_TEST

Gait and Motion Analysis, comprised of 3-dimensional kinematics and kinetics, electromyography, energy expenditure, and physical exam (range of motion, strength, spasticity, etc.)

sterEOS Imaging of Lower Extremities

Intervention Type: DIAGNOSTIC_TEST

Bi-planar imaging of the lower extremities to evaluate femoral anteversion and hip dysplasia and subluxation.

Surveys

Intervention Type: BEHAVIORAL

9 surveys assessing function, activity, participation, pain, quality of life, and treatment history.

Controls (-FDO)

Same as cases but did not undergo an FDO

Motion Analysis

Intervention Type: DIAGNOSTIC_TEST

Gait and Motion Analysis, comprised of 3-dimensional kinematics and kinetics, electromyography, energy expenditure, and physical exam (range of motion, strength, spasticity, etc.)

sterEOS Imaging of Lower Extremities

Intervention Type: DIAGNOSTIC_TEST

Bi-planar imaging of the lower extremities to evaluate femoral anteversion and hip dysplasia and subluxation.

Surveys

Intervention Type: BEHAVIORAL

9 surveys assessing function, activity, participation, pain, quality of life, and treatment history.

Interventions

Motion Analysis

Gait and Motion Analysis, comprised of 3-dimensional kinematics and kinetics, electromyography, energy expenditure, and physical exam (range of motion, strength, spasticity, etc.)

Intervention Type: DIAGNOSTIC_TEST

sterEOS Imaging of Lower Extremities

Bi-planar imaging of the lower extremities to evaluate femoral anteversion and hip dysplasia and subluxation.

Intervention Type: DIAGNOSTIC_TEST

Surveys

9 surveys assessing function, activity, participation, pain, quality of life, and treatment history.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• Diagnosed with bilateral CP (i.e., hemiplegics excluded)
• Minimum age of 25 years presently
• Had a preoperative gait analysis
• Underwent only 1 external, proximal FDO per side
• Minimum 5 years since an FDO
• FDO implants have been removed
• No prior pelvic osteotomy
• Able to speak and read English
• Not pregnant

Control group (-FDO):

• Same as cases, except no FDO
• Matched to cases at baseline (using a matching algorithm)

Exclusion Criteria

• none

• Minimum Eligible Age: 25 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Gillette Children's Specialty Healthcare

OTHER

Sponsor Role: lead

Responsible Party

Tom F Novacheck

Pediatric Orthopedic Surgeon

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Tom F Novacheck, MD

Role: PRINCIPAL_INVESTIGATOR

Gillette Children's Specialty Healthcare

Locations

Gillette Children's Specialty Healthcare

Saint Paul, Minnesota, United States

Countries

United States

Other Identifiers

Study 00000239

Identifier Type: -

Identifier Source: org_study_id