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Piriformis syndrome: muscle thickness or volume does not correlate with response to CT-guided injection

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Skeletal Radiology Aims and scope Submit manuscript

Abstract

Objective

To determine whether size of the piriformis muscle, as characterized by either the coronal width or a segmented volume, correlates with outcomes after CT-guided injections.

Materials and methods

A consecutive series of 81 patients with piriformis syndrome received CT-guided injections of the sciatic nerve and piriformis muscle. Volume and thickness measurements of the piriformis were taken from T1W and T2W pre-injection images by two readers. A logistic regression was used to test volume and size effect on first injection response. A cox proportional hazards model was used to evaluate pain-free survival. Identical analyses were performed to test the effects of muscle mass abnormality, nerve abnormality, body mass index, and presence of a split sciatic nerve.

Results

There were 15/94 negative responses, 31/94 possible positive responses, and 48/94 positive responses to CT-guided injection. The average pain-free survival time was 38.91 ± 64.43 days. There was no significant correlation of first injection responses with muscle thickness or volume. There was no significant correlation in pain-free survival for muscle thickness or volume. There was no significant correlation in first injection response or pain-free survival with body mass index, muscle abnormalities, nerve abnormalities, or split sciatic nerves. The intraclass correlation was excellent between the two readers for both muscle volume (0.95–0.98) and thickness (0.92–0.97).

Conclusion

Piriformis muscle volume or thickness did not significantly correlate with post-injection outcome (first injection response and pain-free survival). Thus, if the patient has clinical symptoms of piriformis syndrome, the size of muscle should not determine whether injection is advisable.

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Abbreviations

MRN:

Magnetic Resonance Neurography

T2W:

T2-Weighted

References

  1. Chang A, Varacallo M. Piriformis injection statpearls. Treasure Island: StatPearls Publishing LLC; 2018.

    Google Scholar 

  2. Chen CK, J Nizar A. Prevalence of piriformis syndrome in chronic low back pain patients. A clinical diagnosis with modified fair test, 2012.

  3. Singh S, Deshmukh P, Ungratwar A, Subramanyam A, Kamath R. Does resilience affect illness perception and well-being in the elderly? J Med Soc. 2013;27(2):94–9.

    Article  Google Scholar 

  4. Boyajian-O’Neill LA, McClain RL, Coleman MK, Thomas PP. Diagnosis and management of piriformis syndrome: An osteopathic approach. J Am Osteopathic Assoc. 2008;108(11):657–64.

    Article  Google Scholar 

  5. Hopayian K, Song F, Riera R, Sambandan S. The clinical features of the piriformis syndrome: a systematic review. Euro Spine J. 2010;19(12):2095–109.

    Article  Google Scholar 

  6. Filler AG. Piriformis and related entrapment syndromes: diagnosis & management. Neurosurg Clin N Am. 2008;19(4):609–22.

    Article  Google Scholar 

  7. Hernando MF, Cerezal L, Perez-Carro L, Abascal F, Canga A. Deep gluteal syndrome: anatomy, imaging, and management of sciatic nerve entrapments in the subgluteal space. Skeletal Radiol. 2015;44(7):919–34.

    Article  Google Scholar 

  8. Fanucci E, Masala S, Sodani G, Varrucciu V, Romagnoli A, Squillaci E, et al. CT-guided injection of botulinic toxin for percutaneous therapy of piriformis muscle syndrome with preliminary MRI results about denervative process. Eur Radiol. 2001;11(12):2543–8.

    Article  CAS  Google Scholar 

  9. Cassidy L, Walters A, Bubb K, Shoja MM, Tubbs RS, Loukas M. Piriformis syndrome: implications of anatomical variations, diagnostic techniques, and treatment options. Surg Radiol Anat. 2012;34(6):479–86.

    Article  Google Scholar 

  10. Filler AG, Haynes J, Jordan SE, Prager J, Villablanca JP, Farahani K, et al. Sciatica of nondisc origin and piriformis syndrome: diagnosis by magnetic resonance neurography and interventional magnetic resonance imaging with outcome study of resulting treatment. J Neurosurg Spine. 2005;2(2):99–115.

    Article  Google Scholar 

  11. Chhabra A, Chalian M, Soldatos T, Andreisek G, Faridian-Aragh N, Williams E, et al. 3-T high-resolution MR neurography of sciatic neuropathy. Am J Roentgenol. 2012;198(4):W357–64.

    Article  Google Scholar 

  12. Yang HE, Park JH, Kim S. Usefulness of magnetic resonance neurography for diagnosis of piriformis muscle syndrome and verification of the effect after botulinum toxin type a injection: two cases. Medicine. 2015;94(38):e1504–e1504.

    Article  CAS  Google Scholar 

  13. Jankovic D, Peng P, van Zundert A. Brief review: Piriformis syndrome: etiology, diagnosis, and management. Canad J Anesthesia/Journal canadien d’anesthésie. 2013;60(10):1003–12.

    Article  Google Scholar 

  14. Jabbari B. Botulinum toxin treatment of piriformis syndrome. In: Jabbari B, editor. Botulinum toxin treatment of pain disorders. New York: Springer; 2015. p. 99–108.

    Google Scholar 

  15. Fishman LM, Anderson C, Rosner B. BOTOX and physical therapy in the treatment of piriformis syndrome. Am J Phys Med Rehabil. 2002;81(12):936–42.

    Article  Google Scholar 

  16. Kirschner JS, Foye PM, Cole JL. Piriformis syndrome, diagnosis and treatment. Muscle Nerve. 2009;40(1):10–8.

    Article  Google Scholar 

  17. Fishman LM, Konnoth C, Rozner B. Botulinum neurotoxin type B and physical therapy in the treatment of piriformis syndrome: a dose-finding study. Am J Phys Med Rehab. 2004;83(1):42–50.

    Article  Google Scholar 

  18. Yoon SJ, Ho J, Kang HY, Lee SH, Kim KI, Shin WG, et al. Low-dose botulinum toxin type A for the treatment of refractory piriformis syndrome. Pharmacotherapy. 2007;27(5):657–65.

    Article  CAS  Google Scholar 

  19. Al-Al-Shaikh M, Michel F, Parratte B, Kastler B, Vidal C, Aubry S. An MRI evaluation of changes in piriformis muscle morphology induced by botulinum toxin injections in the treatment of piriformis syndrome. Diagn Interv Imaging. 2015;96(1):37–43.

    Article  CAS  Google Scholar 

  20. Park CH, Lee SH, Lee SC, Park HS. Piriformis muscle: clinical anatomy with computed tomography in korean population. Korean J Pain. 2011;24(2):87–92.

    Article  Google Scholar 

  21. Skorupska E, Keczmer P, Łochowski RM, Tomal P, Rychlik M, Samborski W. Reliability of MR-based volumetric 3-D analysis of pelvic muscles among subjects with low back with leg pain and healthy volunteers. PLOS ONE. 2016;11(7):e0159587.

    Article  Google Scholar 

  22. Wadhwa V, Scott KM, Rozen S, Starr AJ, Chhabra A. CT-guided perineural injections for chronic pelvic pain. Radiographics. 2016;36(5):1408–25.

    Article  Google Scholar 

  23. Misirlioglu TO, Akgun K, Palamar D, Erden MG, Erbilir T. Piriformis syndrome: comparison of the effectiveness of local anesthetic and corticosteroid injections: a double-blinded, randomized controlled study. Pain Phys. 2015;18(2):163–71.

    Article  Google Scholar 

  24. Brodsky MA, Swope DM, Grimes D. Diffusion of botulinum toxins. Tremor Other Hyperkinet Mov. 2012;2:02.

    Article  Google Scholar 

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Authors and Affiliations

  1. UT Southwestern Medical Center, Dallas, 5323 Harry Hines Blvd, Dallas, TX, 75390, USA

    Rocco Hlis, Kevin Yan, Yin Xi & Avneesh Chhabra

  2. Radiology & Orthopaedic Surgery, Musculoskeletal Radiology, UT Southwestern Medical Center, Dallas, TX, 75390, USA

    Avneesh Chhabra

Authors
  1. Rocco Hlis
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  2. Kevin Yan
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  3. Yin Xi
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  4. Avneesh Chhabra
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Correspondence to Avneesh Chhabra.

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Hlis, R., Yan, K., Xi, Y. et al. Piriformis syndrome: muscle thickness or volume does not correlate with response to CT-guided injection. Skeletal Radiol 51, 1407–1414 (2022). https://doi.org/10.1007/s00256-021-03970-x

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  • DOI: https://doi.org/10.1007/s00256-021-03970-x

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