Diagnosis Of Piriformis Syndrome Research Articles

Evaluation of the Interrater Reliability of Sonographic Measurements of Muscle Thickness of 38 Piriformis Muscles in 19 Patients with Piriformis Syndrome.

BACKGROUND The piriformis muscle is a flat superficial muscle of the deep gluteal muscles that externally rotates the hip. Ultrasound is widely used to identify the piriformis muscle, especially for guidance of the needle during injections; however, its diagnostic use has recently gained popularity. The operator-dependent nature of ultrasound requires demonstration of reliability between operators. This study aimed to evaluate interrater reliability of sonographic measurements of muscle thickness of 38 piriformis muscles in 19 patients with piriformis syndrome. MATERIAL AND METHODS An ultrasound transducer was placed transversely on the sacral spinous process and moved caudo-laterally until the piriformis muscle was visualized under the gluteus maximus while patients were lying in prone position. The thickness of piriformis muscle was measured with a 2 to 5-MHz broadband curvilinear transducer in 3 regions (thickest regions of muscle over the ilium, near the greater trochanter, and near the sacrum). The interrater reliability of measurements of 2 examiners who were blinded to each other's measurements was assessed by intraclass correlation coefficient. RESULTS In total, 114 samples from 38 piriformis muscles of 19 patients with a diagnosis of piriformis syndrome were evaluated by 2 raters in this study. The median (interquartile range) patient age was 41 (15) years. Intraclass correlation coefficient value for overall thickness measurements of piriformis muscle was 0.836. Intraclass correlation coefficient values for 3 different regions were over the ilium, near the greater trochanter, and near the sacrum were 0.777, 0.883, and 0.811, respectively. CONCLUSIONS Ultrasound measurement of piriformis muscle thickness has good interrater reliability.

Evaluation of Piriformis Syndrome in Patients with Low Back Pain Reporting to Public Medical Teaching Institutes in Peshawar

Background: Piriformis Syndrome is a condition in which damage to the piriformis muscle causes pain in buttock and leg. Robinson described the syndrome as having six key characteristics. Before 1934, it was considered that the sciatica can be caused by impingement of sciatic nerve in pelvic, but new diagnostic technology suggests that it can also be caused by distal foraminal entrapment and Piriformis Syndrome. Piriformis syndrome is underrated and mostly neglected by clinician though it can be a cause of low back pain. Objectives: To evaluate the piriformis syndrome in patients complaining of low back pain. Methods: This study was carried out at three different Public Medical Teaching Institutes. Duration of study was 6 months i.e., from March 2018 to August 2018. Sample size of the study was 337 and four different physical tests were performed on patients for diagnosis of Piriformis syndrome. Results: Piriformis Syndrome was diagnosed among 111(32.9%) study participants among which 56 were male and 55 were females. Conclusion: Every third patient of low back pain was diagnosed with Piriformis Syndrome. Male to female ratio of Piriformis Syndrome was 1:3.

‘Hand on hip’ sign: A novel screening test and diagnostic tool in piriformis syndrome

Introduction: Currently there is no gold standard clinical test or investigation available to diagnose piriformis syndrome. We have found a pose used by the patients to describe the pain in the gluteal region in cases of suspected piriformis syndrome. This pose in our study has been described as ‘hand on hip sign’ (HHS). In this study, we aim to assess the significance of this sign in screening of patients with piriformis syndrome. Materials and methods: Seventy patients presenting with pain in the gluteal region with radiculopathy between the age group of 18 years and 60 years were included. All patients were asked to locate the site of the pain in the gluteal region. The demonstration of pain by the patients was noted. If the description matched the description of HHS, it was considered to be positive, else it was considered negative. All patients were subjected to four piriformis-specific confirmatory clinical tests. Considering that there is no single confirmatory test, any patient in whom any two piriformis-specific signs were elicited was considered as a case of piriformis syndrome. Using the data, sensitivity, specificity and positive and negative likelihood ratio of the HHS in the diagnosis of piriformis syndrome were calculated. Inter-test comparison was also made using Cohen’s kappa statistic. Results: HHS was found to have a sensitivity of 86% and a specificity of 75%. It also has a high positive predictive value of 94% and a positive likelihood ratio of 3.44. Inter-test reliability comparison showed that there was a fair to moderate agreement between HHS and other confirmatory piriformis-specific tests. Conclusion: HHS serves as an effective screening test in the identification of piriformis syndrome.

Feasibility and Reliability of an Ultrasound Examination to Diagnose Piriformis Syndrome

We explored the diagnostic performance of ultrasound examinations in the diagnosis of piriformis syndrome (PS). In our single-center retrospective study, 52 patients with a diagnosis of PS and 50 healthy volunteers were enrolled to undergo ultrasound examination of the piriformis and sciatic nerve. The thicknesses of the piriformis and the diameter of the sciatic nerve were measured to compare the differences between the patients with PS and healthy volunteers. The diagnostic performance of ultrasound examinations was assessed by constructing a receiver operating characteristic curve and calculating the area under the curve. In patients with PS, the piriformis and sciatic nerve were enlarged on the abnormal side compared with the asymptomatic side, accompanied by a decreased echo intensity and an unclear perineurium. In addition, the piriformis thickness and sciatic nerve diameter of those with PS were significantly greater than were those of the healthy volunteers. The diagnostic performance of ultrasonography was significant. The area under the receiver operating characteristic curve for piriformis thickness and sciatic nerve diameter to discriminate between the abnormal and asymptomatic sides was 0.778 and 0.871, respectively. Ultrasound examinations can assist in the clinical diagnosis of PS and have the potential to be an alternative method for the diagnosis of PS for most musculoskeletal clinicians.

Piriformis Syndrome: A Narrative Review of the Anatomy, Diagnosis, and Treatment.

Piriformis syndrome is a form of sciatica caused by compression of the sciatic nerve by the piriformis muscle. It is a relatively uncommon, but not insignificant, cause of sciatica. The diagnosis of piriformis syndrome is complicated by the large differential diagnosis of low back and buttock pain with many diagnoses having overlapping symptoms. This narrative review highlights the relevant anatomy, history, physical exam maneuvers, electrodiagnostic findings, and imaging findings that are used to diagnose piriformis syndrome. Also discussed are posterior gluteal myofascial pain syndromes that mimic piriformis syndrome. The review then outlines the different treatment options for piriformis syndrome including conservative treatment, injections, and surgical treatment. In addition, it provides the reader with a clinical framework to better understand and treat the complex, and often misunderstood, diagnosis of piriformis syndrome.

Study of ultrasonic scanning techniques and ultrasonographic characteristics of piriformis

Objective To explore the scanning techniques of piriformis and different ultrasonographic characteristics of normal and abnormal piriformis. Methods A total of 40 cases diagnosed with unilateral piriformis syndrome underwent ultrasonic examination. Then ultrasonic scanning techniques of piriformis were summarized. Contours, thickness and smoothness of epimysium and ultrasonic echo of internal muscle texture of piriformis were compared between the normal and abnormal piriformis. The study was approved by the Third Affiliated Hospital Ethics Committee of Zhejiang Chinese Medical University (Approval no.ZSLL-JS-2016-18). Results Interruption of ultrasonic echo of ilium could be considered as ultrasonographic signs for locating piriformis quickly and accurately. Abnormal piriformis in suffering side of patients with piriformis syndrome showed obscure contours and being thicker than the other side [χ2=9.899, P=0.002; (25.81±0.30)mm vs (22.29±0.27)mm, t=13.604, P=0.000]. Moreover, there were significant differences in comparing smoothness of epimysium and ultrasonic echo of internal muscle texture of piriformis between the two sides(χ2=23.226, P=0.000; χ2=54.848, P=0.000). Conclusions Interruption of ultrasonic echo of ilium may be an important sign for locating piriformis. Ultrasound can display piriformis clearly and distinguish ultrasonographic images of normal piriformis accurately from abnormal piriformis, which can be taken as an basis imaging for clinical diagnosis of piriformis syndrome. Key words: Ultrasonography; Piriformis

The value of ultrasonography in the diagnosis of piriformis syndrome

Objective To discuss the diagnostic value of ultrasonography in piriformis syndrome. Methods Ultrasonography was performed in thirty-eight patients with unilateral piriformis syndrome and forty healthy volunteers. The morphological structures and the internal echoes of their bilateral piriformises and sciatic nerves were observed and their thicknesses were measured. These parameters of the patients and voluteers were recorded and compared. Results The ultrasonographic images of piriformis and sciatic nerve of the healthy voluteers showed no abnormal change. The thickness difference of their bilateral piriformises and sciatic nerves had no statistical significance (P>0.05). The ultrasonography image of the morphological structure and the internal echo of the sick side piriformis and sciatic nerve of the patients with piriformis syndrome showed a change, that the sick side piriformis was significantly thicker than the healthy side piriformis [(25.74±3.12)mm vs (22.48±2.60)mm, P 0.05). Conclusions Ultrasonography can show piriformis and sciatic nerve clearly. The ultrasonographic images and the thickness difference of the bilateral piriformises is helpful to diagnose piriformis syndrome, and can provide more informations for clinic. Key words: Ultrasonography; Piriformis muscle syndrome; Sciatic nerve

English

Piriformis syndrome is a painful musculoskeletal condition resembling sciatica, secondary to sciatic nerve entrapment in piriformis muscle at the greater sciatic notch and responsible for 6%cases of low back pain, also called back pocket sciatica or wallet sciatica, first described in 1928 by Yeoman. It usually occurs due to abnormalities in piriformis muscle such as hypertrophy, inflammation and anatomic variations resulting in irritation and entrapment of sciatic nerve. The diagnosis of piriformis syndrome is made by clinical features, electromyography and nerve conduction velocity, computed tomography, magnetic resonance imaging and bone scan. Management of piriformis syndrome includes nonsurgical and surgical interventions. Non-surgical management includes- nonsteroidal anti-inflammatory drugs, physical therapy, ultrasound, correction of biomechanical abnormality, lifestyle modifications, local anesthetic and/or steroid injection into the piriformis muscle. Surgical management includes-surgical release of piriformis muscle and decompression of the sciatic nerve. Piriformis Syndrome- a review.

Novel variations in the anatomical relationship between the piriformis muscle and sciatic nerve: a cadaveric study (LB2)

The goal of this study is to assess variations in the anatomical relationship between the piriformis muscle and sciatic nerve in a cadaveric population. Currently, Beaton and Anson’s 1937 classification of piriformis‐sciatic arrangements is widely accepted and used for clinical evaluation and diagnosis of Piriformis Syndrome—a dynamic sciatic nerve impingement by the piriformis muscle. This study (n=164 limbs) revealed two clinically important differences to Beaton and Anson’s original findings. First, the Type “B” classification was observed in 18.3% of the cases, representing a 63.9% increase from Beaton and Anson’s original report. Additionally, two Type “B” subsets with potential clinical consequences were observed. Type “B2” included a vascular component, wherein the inferior gluteal artery and vein coursed between the common fibular and tibial divisions of the sciatic nerve (4.3% of total cases). Type “B3” included an additional nerve component, wherein the inferior gluteal nerve coursed between the piriformis muscle and adjacent to the common fibular division, to reach the gluteus maximus muscle (1.0% of total cases). Collectively, these observations expand the current classification of piriformis‐sciatic arrangement, and carry clinical significance for the evaluation and treatment of Piriformis Syndrome.Grant Funding Source: n/a

A Randomized Comparison of the Efficacy of 2 Techniques for Piriformis Muscle Injection

Piriformis muscle injections are most often performed using fluoroscopic guidance; however, ultrasound (US) guidance has recently been described extensively in the literature. No direct comparisons between the 2 techniques have been performed. Our objective was to compare the efficacy and efficiency of fluoroscopic- and US-guided techniques. A randomized, comparative trial was carried out to compare the 2 techniques. Twenty-eight patients with a diagnosis of piriformis syndrome, based on history and physical examination, who had failed conservative treatment were enrolled in the study. Patients were randomized to receive the injection either via US or fluoroscopy. Injections consisted of 10 mL of 1% lidocaine with 80 mg of triamcinalone. The primary outcome measure was numeric pain score, and secondary outcome measures included functional status as measured by the Multidimensional Pain Inventory, patient satisfaction as measured by the Patient Global Impression of Change scale, and procedure timing characteristics. Outcome data were measured preprocedure, immediately postprocedure, and 1 to 2 weeks and 3 months postprocedure. We found no statistically significant differences in numeric pain scores, patient satisfaction, procedure timing characteristics, or most functional outcomes when comparing the 2 techniques. Statistically significant differences between the 2 techniques were found with respect to the outcome measures of household chores and outdoor work. Ultrasound-guided piriformis injections provide similar outcomes to fluoroscopically guided injections without differences in imaging, needling, or overall procedural times.

English

Piriformis Syndrome is a cause for Low back pain which is most of the times misdiagnosed as it may mimic with various other conditions. Abnormal condition of the Piriformis muscle such as hypertrophy, inflammation, or anatomic variations may lead to this condition. Reported incidence rates for Piriformis Syndrome among patients with low back pain vary widely, from 5% to 36%. Etiology of Piriformis Syndrome is also variable. It can be primary due to anatomical problems or secondary due to various other causes like trauma, local ischemia, limb-length discrepancy etc. Diagnosis of Piriformis Syndrome is complex. History with various clinical tests along with MRI, EMG (Electromyography) and Diagnostic blocks may help to diagnose this condition. Here is a review of Piriformis syndrome for better understanding of the problem so that the diagnosis and management are appropriate.

Ultrasound guided piriformis injection with confirmation of needle placement through electromyography: a case report and description of a new technique

A 60 year old male presented to our clinic with lower back, left hip and left buttocks pain for 6 years. The pain was sharp in quality, and radiated toward the left lateral buttock and hip. The pain was rated 6/10, and aggravated by prolonged sitting, squatting, and bending over. On examination, the patient demonstrated tenderness along left lumbar paraspinals and lateral buttocks area. Straight leg raise and FAIR test was positive in LLE. Prior electromyography exam demonstrated a left L5 motor radiculopathy. L-spine MRI revealed multilevel degenerative disc disease. Having previously failed conservative treatment, including PT and gabapentin, a caudal epidural was performed. The patient reported no improvement in his symptoms after the injection. Upon further assessment, diagnosis of piriformis syndrome was considered. A diagnostic injection of lidocaine was performed under ultrasound and EMG guidance into the piriformis muscle. After the injection, the patient had relief of pain. One of the main treatments of piriformis syndrome is injection of local anesthetic or steroids into the piriformis muscle belly. Due to difficulty with needle placement, previous authors have reported various methods in performing piriformis injections: fluoroscopically, motor stimulation, and most recently, ultrasound guidance. With ultrasound alone, even with visualization of needle placement, it is difficult to ensure needle insertion into the piriformis muscle, as opposed to surrounding muscles, specifically the gluteus medius and gluteus maximus. To our knowledge, this is the first report of combined use of ultrasound with EMG confirmation of needle placement for a piriformis injection. Our technique offers the advantage of decreased radiation exposure when compared to fluoroscopy and verification of needle placement into the piriformis when compared to injections without EMG. In addition, our case presentation emphasizes the ability for piriformis syndrome to mimic other diagnosis. A 60 year old male presented to our clinic with lower back, left hip and left buttocks pain for 6 years. The pain was sharp in quality, and radiated toward the left lateral buttock and hip. The pain was rated 6/10, and aggravated by prolonged sitting, squatting, and bending over. On examination, the patient demonstrated tenderness along left lumbar paraspinals and lateral buttocks area. Straight leg raise and FAIR test was positive in LLE. Prior electromyography exam demonstrated a left L5 motor radiculopathy. L-spine MRI revealed multilevel degenerative disc disease. Having previously failed conservative treatment, including PT and gabapentin, a caudal epidural was performed. The patient reported no improvement in his symptoms after the injection. Upon further assessment, diagnosis of piriformis syndrome was considered. A diagnostic injection of lidocaine was performed under ultrasound and EMG guidance into the piriformis muscle. After the injection, the patient had relief of pain. One of the main treatments of piriformis syndrome is injection of local anesthetic or steroids into the piriformis muscle belly. Due to difficulty with needle placement, previous authors have reported various methods in performing piriformis injections: fluoroscopically, motor stimulation, and most recently, ultrasound guidance. With ultrasound alone, even with visualization of needle placement, it is difficult to ensure needle insertion into the piriformis muscle, as opposed to surrounding muscles, specifically the gluteus medius and gluteus maximus. To our knowledge, this is the first report of combined use of ultrasound with EMG confirmation of needle placement for a piriformis injection. Our technique offers the advantage of decreased radiation exposure when compared to fluoroscopy and verification of needle placement into the piriformis when compared to injections without EMG. In addition, our case presentation emphasizes the ability for piriformis syndrome to mimic other diagnosis.

Spondyloarthritis in a Patient With Unilateral Buttock Pain and History of Crohn Disease

Patients with inflammatory spinal conditions related to spondyloarthritis are rarely seen by primary care practitioners. However, patients with a history of inflammatory bowel disease and chronic low back or buttock pain should be examined carefully for the presence of spondyloarthritis, as proper management may include referral to a rheumatologist and appropriate medical intervention. A 27-year-old woman with a 6-month history of posterior buttock pain was referred for physical therapy with a diagnosis of piriformis syndrome. During the second physical therapy visit, a nonmechanical source of lumbopelvic pain was suspected, and the patient was referred for medical consultation. The patient underwent evaluation by a rheumatologist and was eventually diagnosed with spondyloarthritis associated with inflammatory bowel disease. The patient initiated treatment with anti-tumor necrosis factor medication to address the spondyloarthritis. Medical management resulted in significant improvement in all outcome measures. Clinical suspicion of spondyloarthritis is raised when specific historical, examination, and imaging findings are present. The posttest probability of spondyloarthritis is increased with the presence of inflammatory back pain and specific spondyloarthritic features, such as a positive history of inflammatory bowel disease, radiographic evidence of sacroiliitis, and improvement with anti-inflammatory medication. Referral of patients with these findings for a rheumatological evaluation is warranted, as these diseases are managed effectively with specific treatment.

Sciatic Pain Caused by Piriformis Syndrome

Purpose: Sciatic pain rarely develops from piriformis syndrome; thus, its differential diagnosis from other diseases associated with sciatic pain is essential. We analysed the clinical symptoms and radiological findings for the differential diagnosis of piriformis syndrome, and assessed the results of its treatment. Materials and Methods: We analysed five patients diagnosed with piriformis syndrome. Four patients were treated with a tenotomy. Of these, three had a history of misdiagnosis. The hypertrophied piriformis muscle was revealed with a compressed sciatic nerve in the operative field. We performed a tenotomy of the piriformis at the site of the tendinous insertion to decompress the sciatic nerve. Results: At the average follow up was 23.5 months, at which time no patients had any problems relating to tenderness and sciatic pain, and were able to return to normal activity one month postoperatively. All patients evaluated their postoperative clinical state as being better. Conclusion: Multiple approaches are essential for the diagnosis of piriformis syndrome. We can obtain the satisfactory results through a tenotomy of the piriformis for the decompression of the sciatic nerve in intractable cases as a conservative treatment.

Piriformis syndrome in a patient after cesarean section under spinal anesthesia

Objectives The diagnosis, pathogenesis, and treatment of piriformis syndrome as a cause of persistent buttock and hip pain after spinal anesthesia are presented in this case report. Case report A 29-year-old woman presented 5 days after cesarean delivery with sudden onset of pain in the left buttock and left hip radiating to the posterior knee with fever. She was subsequently diagnosed with piriformis syndrome. Conclusions Back pain with radiation into the buttocks after spinal anesthesia is frequently attributed to the spinal procedure itself. However, prolonged sitting and weight bearing in the upright position after cesarean delivery can cause sciatic nerve compression at the sacroiliac joint with concomitant irritation, inflammation, and spasm of the piriformis muscle. Piriformis syndrome is frequently underdiagnosed in the obstetric population. Because the diagnosis of piriformis syndrome is based mainly on clinical signs and symptoms, the clinician must have a high index of suspicion.

Piriformis syndrome: assessment of current practice and literature review.

Although piriformis syndrome was initially described in 1928, it has remained a nebulous and controversial diagnosis. A literature review reveals that there is no consensus on the diagnosis or treatment of piriformis syndrome. In addition, a survey of 75 physiatrists revealed that whether the diagnosis of piriformis syndrome even exists is controversial. This survey and literature review examines the diagnosis and treatment of piriformis syndrome. The fact that it remains controversial is likely due to a lack of objective clinical trials.

Piriformis syndrome

The author presents a case of a female runner with left buttock pain aggravated by exercise. She underwent extensive testing by other physicians and received cortisone injections on two occasions. The patient was referred to the podiatry department because of continued discomfort and the inability to run. Examination revealed pain on hip flexion and abduction against resistance. Because of the possibility of piriformis syndrome, she started stretching exercises, reduced her activity, and the pain disappeared. The diagnosis of piriformis syndrome was confirmed by a general surgeon.