Intraoperative Neuromonitoring of Sacral Reflexes to Predict Post Operative Function in Patients Undergoing Sacrectomy for Pelvic Bone Malignancy or Patients Undergoing Spinal Procedures Without Sacral Root Involvement
Bone Neoplasm · Metastatic Malignant Neoplasm in the Bone
What this study involves
The registry says this study is recruiting. Individual locations may have different availability.
- Study type
- Interventional
- Phase
- Not applicable
- Age range
- 18 years - Not specified
- Sex eligible
- All sexes
- Healthy volunteers
- Not accepted
- Participants
- 50 Estimated
These are starting points, not an eligibility decision. The research team must review the full requirements.
About the research
This clinical trial tests how well monitoring the sacral reflexes during surgery (intraoperatively) works to predict the post operative function for patients undergoing removal of the lowest part of the spine (sacrectomy) for pelvic bone cancers or patients undergoing spinal procedures. These surgical procedures can lead to damage to sacral root nerves which can result in impairment to the lower extremities, bowel, bladder, and sexual function. Intraoperative monitoring of sacral reflexes can provide objective, real-time information about pelvic nerve function during surgery. This can aid surgical decision-making and help surgeons better prepare patients to understand the changes that may have occurred to their function as a result of surgery. Intraoperative neuromonitoring may work well to predict postoperative function in patients undergoing sacrectomy for pelvic bone malignancy or patients undergoing spinal procedures.
Read the full description
PRIMARY OBJECTIVE:
I. To evaluate the feasibility of acquiring analyzable sacral reflex neuromonitoring data at baseline and case closure during surgery.
SECONDARY OBJECTIVES:
I. To characterize sacral reflex parameters amplitude, latency, waveform morphology, and Nerveana Power Index (NPI) at baseline under standardized intraoperative neuromonitoring conditions in patients undergoing spinal procedures without sacral nerve root involvement and patients undergoing sacrectomy.
II. To describe intraoperative changes in sacral reflex parameters from baseline to end-of-case during standardized intraoperative neuromonitoring in patients undergoing sacrectomy.
III. To characterize the relative contribution of individual sacral nerve roots to sacral reflex responses during intraoperative stimulation in patients undergoing sacrectomy.
IV. To characterize longitudinal changes in postoperative functional outcomes in patients undergoing sacrectomy.
EXPLORATORY OBJECTIVES:
I. To explore the association between intraoperative sacral reflex changes and postoperative functional outcomes in patients undergoing sacrectomy.
II. To explore the association between sacrifice of higher- versus lower-contributing sacral nerve roots and postoperative functional outcomes in patients undergoing sacrectomy.
OUTLINE:
Patients undergo neuromonitoring of the sacral reflexes at predefined time points during standard of care surgery.
After completion of study treatment, patients are followed up at 21 days, 6 weeks and 3, 6 and 12 months.
Who may be able to participate?
The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.
Inclusion Criteria:
- Documented informed consent of the participant and/or legally authorized representative.
- Assent, when appropriate, will be obtained per institutional guidelines
- Age: ≥ 18 years
- Ability to complete study questionnaires
- Willingness to comply with all study procedures, including postoperative patient-reported outcome (PRO) assessments
- Undergoing surgery at City of Hope involving either:
- Complete or partial sacrectomy for primary or metastatic bone tumors, or
- Thoracolumbar intervention in which the sacral roots are not exposed or manipulated (reference cohort)
Exclusion Criteria:
- Prior sacrectomy or prior surgery resulting in complete sacral nerve transection
- For thoracolumbar cohort patients, prior diagnosis or patient report of bowel or bladder dysfunction
- Cognitive or psychiatric conditions preventing reliable completion of PRO instruments
Treatment, groups and participation
The registry may describe treatments and study duration without a complete visit calendar. Ask the study team for the exact schedule, procedures, risks, costs and alternatives. Keep your usual care plan unless your treating clinician tells you otherwise.
- Assignment
- Not applicable
- Masking
- No masking
Diagnostic (Intraoperative neuromonitoring)
Patients undergo neuromonitoring of the sacral reflexes at predefined time points during standard of care surgery.
Procedure: Intraoperative Nerve Monitoring · Procedure: Surgical Procedure · Other: Survey Administration
Intraoperative Nerve Monitoring PROCEDURE
Undergo intraoperative neuromonitoring
Surgical Procedure PROCEDURE
Undergo standard of care surgery
Survey Administration OTHER
Ancillary studies
What researchers are measuring
Outcome measures describe what is being studied. They are not proof that a treatment works.
Primary measures
Reproducible and interpretable bulbocavernosus reflex (BCR) and external urethral sphincter (EUS) reflex responses (feasibility)
Time frame: From baseline, Up to 1 year
Reproducible is defined as the ability to elicit a reflex response on repeated stimulation with consistent waveform presence and morphology at a given timepoint. Interpretable is defined as a recorded reflex response that is distinguishable from background noise and artifact and permits determination of response presence or absence and measurement of latency and amplitude. A two-sided 95% Clopper-Pearson confidence interval will be provided as a measure of precision.
Secondary measures
Distribution of BCR reflex parameters
Time frame: From baseline, Up to 1 year
Amplitude, latency, frequency distribution, etc, measured via intraoperative neuromonitoring (IONM). ), Analyses will first be conducted separately within thoracolumber and sacrectomy patient groups. Descriptive statistics will be reported for BCR for each group. Next, to compare the mean values between the two groups, t-test or Mann-Whitney U-test will be implemented depending on the distribution of these parameters. Additionally, within the sacrectomy group, the changes of these parameters from baseline to the end-of-case will be assessed either through paired t-test or Wilcoxon's signed rank test, depending on the distribution of each parameter.
Distribution of EUS reflex parameters
Time frame: From baseline, Up to 1 year
Amplitude, latency, frequency distribution, etc, measured via IONM. Analyses will first be conducted separately within thoracolumber and sacrectomy patient groups. Descriptive statistics will be reported for EUS for each group. Next, to compare the mean values between the two groups, t-test or Mann-Whitney U-test will be implemented depending on the distribution of these parameters. Additionally, within the sacrectomy group, the changes of these parameters from baseline to the end-of-case will be assessed either through paired t-test or Wilcoxon's signed rank test, depending on the distribution of each parameter.
Change in BCR reflex parameters
Time frame: From baseline, Up to 1 year
Analyses will first be conducted separately within thoracolumber and sacrectomy patient groups. Descriptive statistics will be reported for BCR for each group. Next, to compare the mean values between the two groups, t-test or Mann-Whitney U-test will be implemented depending on the distribution of these parameters. Additionally, within the sacrectomy group, the changes of these parameters from baseline to the end-of-case will be assessed either through paired t-test or Wilcoxon's signed rank test, depending on the distribution of each parameter.
Change in EUS reflex parameters
Time frame: From baseline, Up to 1 year
Analyses will first be conducted separately within thoracolumber and sacrectomy patient groups. Descriptive statistics will be reported for EUS for each group. Next, to compare the mean values between the two groups, t-test or Mann-Whitney U-test will be implemented depending on the distribution of these parameters. Additionally, within the sacrectomy group, the changes of these parameters from baseline to the end-of-case will be assessed either through paired t-test or Wilcoxon's signed rank test, depending on the distribution of each parameter.
Relative contribution of individual right sacral nerve roots to BCR amplitude
Time frame: During intraoperative stimulation, Up to Day 21
Amplitudes among sacrectomy patients will be descriptively reported.
Relative contribution of individual left sacral nerve roots to BCR amplitude
Time frame: During intraoperative stimulation, Up to Day 21
Amplitudes among sacrectomy patients will be descriptively reported.
Relative contribution of individual right sacral nerve roots to EUS amplitude
Time frame: During intraoperative stimulation, Up to Day 21
Amplitudes among sacrectomy patients will be descriptively reported.
Relative contribution of individual left sacral nerve roots to EUS amplitude
Time frame: During intraoperative stimulation, Up to Day 21
Amplitudes among sacrectomy patients will be descriptively reported.
Bowel function scores
Time frame: From baseline, Up to 1 year
Assessed by Memorial Sloan Kettering Bowel Function Instrument. Will be described by graphs and descriptive statistics at each time point.
Bladder function scores
Time frame: From baseline, up to 1 year
Assessed by International Consultation on Incontinence Questionnaire. Will be described by graphs and descriptive statistics at each time point.
Sexual function scores
Time frame: From baseline, up to 1 year
Assessed by Female Sexual Function Index (female patients only) and International Index of Erectile Function (male patients only). Will be described by graphs and descriptive statistics at each time point.
Lower extremity function
Time frame: From baseline, up to 1 year
Assessed by Toronto Extremity Salvage Score for the Lower Extremity. Will be described by graphs and descriptive statistics at each time point.
Quality of life
Time frame: From baseline, up to 1 year
Assessed by Functional Assessment of Cancer Therapy-General. Will be described by graphs and descriptive statistics at each time point.
Postoperative urologic function
Time frame: From baseline, up to 1 year
Assessed by post-void residual (PVR) or cystometry. Will be described by graphs and descriptive statistics at each time point.
Review the complete result tables and limitations in the official record.
Open official results ↗Research locations (1)
The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.
1 locations
City of Hope Medical CenterDuarte, California, United StatesRecruiting
Study team and timeline
- Lead sponsor
- City of Hope Medical Center
- Study start
- Jan 10, 2027 Estimated
- Primary completion
- Jun 10, 2029 Estimated
- Study completion
- Jun 10, 2029 Estimated
- First posted
- Jul 16, 2026 Actual
- Last updated
- Nov 10, 2026 Actual
Official study contacts
No central contact is listed. Check the locations and the official record.
Official study title
Phase 2a Prospective Study of Intraoperative Neuromonitoring of the Bulbocavernosus and External Urethral Sphincter Reflexes
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Source: ClinicalTrials.gov API v2. Information is submitted by sponsors and investigators. NLM does not approve the safety or science of all listed studies. Registry disclaimer.
Retrieved: Nov 12, 2026 · Last registry update: Nov 10, 2026