Case reportChiropractic management of a US Army veteran with low back pain and piriformis syndrome complicated by an anatomical anomaly of the piriformis muscle: a case study
Introduction
Piriformis syndrome is an uncommon cause of low back pain and sciatica that results from entrapment and/or irritation of the sciatic nerve in the region of the greater sciatic foramen.1, 2, 3, 4 Although no definitive causative factors are known for this syndrome, the usual source is thought to be an abnormal condition of the piriformis muscle. A common basis of the problem appears to be trauma to the piriformis muscle that results in spasm, edema, and contracture of the muscle, which can cause subsequent compression and entrapment of the sciatic nerve.2 Other possible etiologies include reflex spasm of the piriformis muscle and an abnormal course of the sciatic nerve through the piriformis muscle. Altered biomechanics of the lower limb, low back, and pelvic regions can lead to stretching and shortening of the piriformis muscle, which can also lead to piriformis syndrome. Although, in 1928, Yeoman5 first described the clinical picture of what would later be called piriformis syndrome, this diagnosis still remains somewhat controversial. This controversy stems from several factors that include variable and sometimes unclear cause, similarity to other more easily recognizable causes of sciatica, lack of consistent objective diagnostic findings, and relative rarity. Piriformis syndrome had been thought to be a purely clinical diagnosis; but more recently, magnetic resonance imaging (MRI) has begun to be used to help with the diagnosis of this problem.6
The piriformis muscle is a pear-shaped muscle in the gluteal region that lies inferior to and in the same plane as the gluteus medius muscle. Normally, the piriformis muscle arises from the anterior surface of the second through fourth sacral segments in the regions between and lateral to the anterior sacral foramina (Fig 1). It also arises from the superior margin of the greater sciatic notch, the anterior sacroiliac ligament, and sometimes the anterior surface of the sacrotuberous ligament. The piriformis muscle exits the pelvis through the greater sciatic foramen, which it mostly fills, to insert on the upper border of the greater trochanter of the femur. Usually, the sciatic nerve emerges from the greater sciatic foramen inferior to the piriformis muscle (Fig 2). There are several variations on this relationship that have been described.7 The most common variation, which occurs in more than 10% of the population,8 is that the common fibular portion of the sciatic nerve emerges through the piriformis muscle. Interestingly, a recent meta-analysis suggests that variations in how the sciatic nerve exits the pelvis through the greater sciatic foramen in relation to the piriformis muscle present no increase in risk of piriformis syndrome.9
The authors were unable to locate any studies that addressed conservative management of a patient with accessory superior bundles of the piriformis muscle. One case study was found in which a patient was treated for posttraumatic piriformis syndrome with successful resolution of symptoms after treatment for 5 months.12 Another case study describes a patient with sacroiliac joint dysfunction with associated piriformis syndrome that mimicked an intervertebral disk syndrome.13 The purpose of this article is to present the case of a patient with an anatomical anomaly of the piriformis muscle that had a piriformis syndrome and was managed with chiropractic care.
Section snippets
Case report
A 32-year-old man reported to a private practice chiropractic clinic with a chief complaint of low back pain, which began 5 years prior as a result of injuries during Airborne School in the US Army resulting in a 60% disability rating from the Veterans Administration. The patient noted that most activities increased his pain, whereas stretching, massage, ice, heat, prescription muscle relaxers, and over-the-counter medications decreased his pain. He said that it varied greatly throughout the
Discussion
This is an unusual case because the patient also has anomalous accessory bundles of the piriformis muscle. Initially, this anatomical variant was thought to be asymptomatic; but over the course of several years, the patient has experienced several episodes of symptoms that did appear to be due to the variant piriformis muscle and was considered a true piriformis syndrome. The patient has been managed successfully with conservative chiropractic care, although the underlying cause of the
Limitations
The current case report is limited by the fact that it only involves one patient and can therefore not be applied to all cases of piriformis syndrome. A second limitation is a lack of objective outcome assessment measures. Because this patient has been treated for multiple conditions, the use of more detailed objective assessment tools was not practical, the patient discontinued care before his estimated release date, or the timing did not always correspond with the cessation of one complaint
Conclusion
This case study shows that even though an anomalous piriformis muscle exists, it may not be symptomatic. Even if it is not symptomatic at a given point of time, this type of anomaly does represent an altered biomechanic status and may put the patient at risk for a piriformis syndrome in the future. Although surgery is an option, this case shows that conservative chiropractic care may be an option for management of similar cases.
Funding sources and potential conflicts of interest
No funding sources or conflicts of interest were reported for this study.
Acknowledgment
The authors thank Kenneth Young, DC, DACBR, MAppSc (MedImaging) Senior Lecturer, Academic Chair for BSc (Chiro) at the School of Chiropractic and Sports Science, Murdoch University, Australia, for his assistance in reviewing this patient's MRI films.
References (13)
- et al.
Diagnosis and treatment of piriformis syndrome
Neurosurg Clin N Am
(2001) - et al.
Diagnosis and management of posttraumatic piriformis syndrome: a case study
J Manipulative Physiol Ther
(2006) - et al.
Piriformis syndrome: an annotated bibliography
J Can Chiropr Assoc
(1999) - et al.
Piriformis syndrome
- et al.
Diagnosis and management of piriformis syndrome: an osteopathic approach
J Am Osteopath Assoc
(2008) The relation of arthritis of the sacroiliac joint to sciatica: with an analysis of 100 cases
Lancet
(1928)
Cited by (9)
Visualizing Anatomic Variants of the Sciatic Nerve Using Diagnostic Ultrasound During Piriformis Muscle Injection: An Example of 4 Cases
2022, Journal of Chiropractic MedicineCitation Excerpt :The dramatic and almost immediate relief of pain after infiltration of the PM with a local anesthetic (LA) has been considered a reference test for diagnosis.5 Once a diagnosis of PS is made, the mainstay approach is nonsurgical multidisciplinary care,7 including physical therapy, pharmacological agents, manual overpressure, massage, acupuncture, chiropractic care, and dry needling.7-10 As in other patients with trigger point problems, one of the therapy options is the injection of LA into the focal point of hyperirritability deep in the belly of the muscle.11
Unusual accessory piriformis muscle: A case report
2017, Journal of the Anatomical Society of IndiaCitation Excerpt :In the case of Battaglia et al.4 PM was divided into two discrete bellies by the CFN, while the TN passed inferior and deep to the caudal border of the PM. Chapman and Bakkum6 presented MRI finding of patient with PS due to the accessory superior bundles of the right PM. Additionally, in another study including 30 cadavers, 20% of the PMs were found to have double heads and CFN were located between these two heads.8
Effects of ultrasound-guided platelet rich plasma injection in patients with piriformis syndrome
2022, Journal of Back and Musculoskeletal RehabilitationFour symptoms define the piriformis syndrome: an updated systematic review of its clinical features
2018, European Journal of Orthopaedic Surgery and TraumatologyFrequency of piriformis tightness in professionals middle aged women
2018, Rawal Medical Journal