Prehabilitation for patient positioning: pelvic exercises assist in minimizing inter-fraction sacral slope variability during radiation therapy
Reproducible patient positioning is essential for precision in radiation therapy (RT) delivery. We tested the hypothesis that a structured daily pre-treatment stretching regimen is both feasible and effective for minimizing variability in positioning, as measured by sacral slope angles (SSA). Eight female subjects undergoing pelvic radiotherapy performed a structured daily hip exercise regimen (extension and external rotation) immediately prior to both simulation imaging and daily treatment, throughout their RT course. This exercising cohort was compared to a retrospective review of 20 subjects (17 women and 3 men) undergoing RT, who had usual care. SSA measurements from daily pre-treatment imaging were compared to SSA measurements from the simulation CT. The average variation in SSA among the intervention subjects was 0.91° (± 0.58°), with a range among subjects of 0.57°–1.27°. The average variation for the control subjects was 2.27° (± 1.43°), ranging 1.22°–5.09°. The difference between the two groups was statistically significant (p = 0.0001). There was a statistically significant SSA variation between groups at each week of treatment. There was no significant variation among the intervention subjects between week 1 and later weeks, whereas subjects in the control group demonstrated significant SSA variation between week 1 and later weeks. We demonstrated a significant decrease in the variability of SSA by implementing a simple pre-treatment exercise program, while control subjects exhibited increasing variation in SSA over the course of treatment. We conclude that there is a potential benefit of prehabilitation during pelvic RT; however, a larger randomized control trial is required to confirm the findings.
Clinical Trial: This research project was approved by the University of Massachusetts Medical School IRB (IRB ID H00012353) on January 21, 2017. The study is listed on ClinicalTrials.gov, provided by the U.S. National Library of Medicine, found with identifier NCT03242538.
KeywordsPrehabilitation Pelvic cancer radiotherapy Inter-fraction reproducibility Exercise therapy Patient Setup
This study would not have been possible without the cooperation of our patients; we are very grateful for their diligent participation in our research. We appreciate efforts by Mashhood Bodla and Priya Moni, PhD, who began work on this research topic. We thank the University of Massachusetts Medical School for the Joseph P Healey Award which funded medical student summer research stipends. Andrew Boylan and Wasih Kamran assisted with patient education and ensuring daily patient exercise compliance. Finally, we thank all staff within the Department of Radiation Oncology at UMass Memorial Health Care in Worcester, MA for their support and assistance.
This study was funded by the Joseph P Healey Award for medical student summer research. This is an institutional grant supported by the University of Massachusetts Medical School.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee (include name of committee + reference number) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
- 5.Jaffray DA, Gospodarowicz MK. Radiation therapy for cancer. In: Gelband H, Jha P, Sankaranarayanan R, et al., editors. Cancer: disease control priorities, vol. 3. Washington, DC: The International Bank for Reconstruction and Development/The World Bank; 2015. https://doi.org/10.1596/978-1-4648-0349-9_ch14.CrossRefGoogle Scholar
- 17.Bazire L, Xu H, Foy J-P, Amessis M, Malhaire C, Cao K, et al. Pelvic insufficiency fracture (PIF) incidence in patients treated with intensitymodulated radiation therapy (IMRT) for gynaecological or anal cancer: single-institution experience and review of the literature. Br J Radiol. 2017;90:20160885.CrossRefGoogle Scholar
- 19.Frøseth TC, Strickert T, Solli KS, Salvesen Ø, Frykholm G, Reidunsdatter RJ. A randomized study of the effect of patient positioning on setup reproducibility and dose distribution to organs at risk in radiotherapy of rectal cancer patients. Radiat Oncol. 2015;10:217. https://doi.org/10.1186/s13014-015-0524-3.CrossRefPubMedPubMedCentralGoogle Scholar