The piriformis syndrome is overdiagnosed

Restoring Functionality: A Case Report on Physiotherapeutic Rehabilitation for L5-S1 Anterolisthesis Management

Anterolisthesis is a condition where a vertebra in the spine slips forward relative to the vertebra below it. Anterolisthesis is often described in terms of the direction of the slippage and the affected vertebrae, such as L5-S1 anterolisthesis, which indicates the slippage occurring between the fifth lumbar vertebra (L5) and the sacral bone (S1). Anterolisthesis can result from various factors, trauma, or congenital abnormalities. The symptoms associated with anterolisthesis can include lower back pain, stiffness, muscle tightness, and neurological symptoms if the slippage compresses nearby nerves. The piriformis muscle, situated deep within the buttocks, plays a crucial role in this scenario, as its contraction or inflammation can exacerbate the compression of the sciatic nerve, intensifying the pain and discomfort experienced by the individual. Patients with L5-S1 anterolisthesis and bilateral piriformis syndrome commonly report challenges in daily activities involving hip movement, such as walking, sitting, or standing for prolonged periods of time. The combined effects of vertebral slippage and piriformis involvement contribute to altered gait patterns and may lead to difficulties in maintaining a stable and pain-free posture. Effective management often necessitates a comprehensive approach, encompassing physical therapy, pain management strategies, and, in severe cases, surgical intervention. We report a case of a 75-year-old male who complained of pain in his back radiating to both lower limbs with a history of slipping and falling in the bathroom one month prior, sustaining an injury to his back, and who visited the orthopedics department of Acharya Vinoba Bhave Rural Hospital (AVBRH), Sawangi, Wardha, where an investigation was done and an X-ray revealed L5-S1 anterolisthesis. Physiotherapy plays a crucial role in reducing pain, improving the range of motion and muscle strength, decreasing muscle tightness, and enhancing the quality of life. The goal of physiotherapeutic rehabilitation for L5-S1 anterolisthesis management is to optimize functional recovery, reduce pain, improve the range of motion and muscle strength, and improve the overall quality of life for individuals with this condition.

Piriformis syndrome

Piriformis syndrome is a condition that is proposed to result from compression of the sciatic nerve, either in whole or in part, in the deep gluteal space by the piriformis muscle. The prevalence of piriformis syndrome depends upon the diagnostic criteria being used and the population studied but is estimated by some to be 5%-6% in all cases of low back, buttock, and leg pain and up to 17% of patients with chronic low back pain. While the sciatic nerve may pierce the piriformis muscle in about 16% of healthy individuals, this frequency is no different in those with the syndrome; thus, the relationship to this anatomic finding is unclear. The most common symptoms are buttock pain, external tenderness over the greater sciatic notch, and aggravation of the pain through sitting. Many clinical signs are reported for piriformis syndrome, but the sensitivity and specificity are unclear, in part because of the lack of a uniformly accepted case definition. In the majority of cases in the literature, it appears that the diagnosis is more ascribed to a myofascial condition rather than a focal neuropathy. Electrodiagnostic studies can be useful to exclude other causes of symptoms, but there is no well-accepted test to confirm the presence of piriformis syndrome. Ultrasound imaging may show thickening of the piriformis muscle, but further research is required to confirm that this is correlated with the clinical diagnosis. Magnetic resonance imaging and neurography may hold promise in the future, but there are not yet sufficient data to support adopting these methods as a standard diagnostic tool. The initial treatment of piriformis syndrome is typically conservative management with the general rehabilitation principles similar to other soft tissue musculoskeletal conditions. Local anesthetic, botulinum toxin, and/or corticosteroid injections have been reported by some to be beneficial for diagnostic or treatment purposes. Surgical interventions have also been used with variable success.

Looking beyond Piriformis Syndrome: Is It Really the Piriformis?

Piriformis syndrome is a common differential diagnosis related to sciatica. The following review provides a concise synopsis of the diagnosis, management, history, and alternatives to diagnosis of piriformis syndrome. A search of the literature for research articles related to piriformis syndrome and associated differential diagnosis of sciatica was conducted. A thorough review of the included articles found that the condition known as piriformis syndrome is over-diagnosed and that potential anatomic and biomechanical variations originating in the pelvic region might be related to the complaint of sciatica. The criteria for diagnosis are based on findings from both physical examination and radio imaging. Piriformis syndrome resembles a variety of clinical conditions; therefore, conduct of future studies should include development of a validated method for evaluation as well as clinical criteria for diagnosis of piriformis syndrome.

Little needle-scalpel for piriformis syndrome: A protocol for systematic review and meta-analysis

BACKGROUND

Piriformis syndrome (PS) is a condition in which the sciatic nerve is compressed when passing through the inferior mouth of the piriformis muscle, mainly caused by pain in one hip and leg. In severe cases, patients may experience severe buttock and lower limb pain, discomfort, difficulty walking, and claudication. It is estimated that the annual incidence of low back pain and sciatica is about 40 million cases, and the annual incidence of piriformis syndrome is about 2.4 million cases. The aim of this systematic review is to assess the effectiveness and safety of Little needle-scalpel therapy for Piriformis syndrome.

METHODS

Two reviewers will electronically search the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; China National Knowledge Infrastructure (CNKI); Chinese Biomedical Literature Database (CBM); Chinese Scientific Journal Database (VIP database); and Wan-Fang Database from the inception, without restriction of publication status and languages. Additional searching including researches in progress, the reference lists, and the citation lists of identified publications. Study selection, data extraction, and assessment of study quality will be performed independently by 2 reviewers. If it is appropriate for a meta-analysis, RevMan 5.4 statistical software will be used; otherwise, a descriptive analysis will be conducted. Data will be synthesized by either the fixed-effects or random-effects model according to a heterogeneity test. The results will be presented as risk ratio (RR) with 95% confidence intervals (CIs) for dichotomous data and weight mean difference (WMD) or standard mean difference (SMD) 95% CIs for continuous data.

RESULTS

This study will provide a comprehensive review of the available evidence for the treatment of Little needle-scalpel with piriformis syndrome.

CONCLUSIONS

The conclusions of our study will provide an evidence to judge whether Little needle-scalpel is an effective and safe intervention for patients with piriformis syndrome.

ETHICS AND DISSEMINATION

This systematic review will be disseminated in a peer-reviewed journal or presented at relevant conferences. It is not necessary for a formal ethical approval because the data are not individualized.

TRIAL REGISTRATION NUMBER

INPLASY2020110092.

The deep gluteal (piriformis) syndrome

Piriformisa syndrome is a subgroup of the deep gluteal syndrome, an important differential diagnosis of sciatica. Piriformis is a short external rotator muscle of the hip joint passing close to the sciatic nerve as it passes through the great sciatic foramen. Compression causes numbness, ache or tingling in the buttocks, posterolateral aspect of the leg and foot. The causes of sciatic nerve entrapment in the deep gluteal syndrome are best shown by endoscopic exploration. The frequency of anatomical variants in normal subjects however, should caution that such anomalies are not necessarily the cause of symptoms.

‘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.

Dexamethasone Versus Magnesium Sulfate as an Adjuvant to Local Anesthetics in the Ultra-Sound Guided Injection of Piriformis Muscle for the Treatment of Piriformis Syndrome

Background:

Piriformis Syndrome (PS) is an underdiagnosed cause of buttock, thigh and leg pain, most probably because it is thought to be a rare cause of sciatica. PS is widely believed to be myofascial in origin.

Materials and Methods:

This prospective, randomized, controlled, double-blind study was conducted at the pain management department. 50 patients aged from 20 to 60 years old were included in this study. The selected patients were randomly allocated into 2 groups containing 25 patients each; Group D received a total of 5 mL which included 2mL lidocaine 2%, 2mL (8 mg) dexamethasone and 1mL normal saline 0.9%, and Group M received a total of 5mL which included 2mL lidocaine 2%, 3mL magnesium sulphate (MgSO4) (2.5%) . Patients demographic characteristics, baseline physical examination findings of the patients as well as the duration of pain were all recorded. Patients were re-assessed immediately after injection, 1 week, 1 month, and 3 months after the injection. Numeric Rating Scale (NRS) values were used at each evaluation time to assess the pain, while patients were in sitting, standing, and lying positions. All patients were assessed immediately and for 4 hours post-injection for any side effects related to the drugs used.

Results:

In the pre-injection time, immediately after and 1 week after injection, there were no statistically significant differences between groups D and M in pain values. While, on comparison between both groups, group M, was significantly better than group D, in NRS values 1 month and 3 months after injection. In group D, pain score values were significantly better immediately, 1 week, and 1 month after injection compared to the pre-injection values, while these values were not significantly different 3 months after injection compared with the pre-injection values. In group M, pain score values were significantly better immediately, 1 week, 1 month, and 3 months after injection compared to the pre-injection values.

Conclusion:

Magnesium sulfate was more effective, especially for long term pain relief (3 months) when compared to dexamethasone as they were used as adjuvants to lidocaine, if injected into the piriformis muscle (PM) guided by ultrasound in the management of PS refractory as initial conservative treatment.

Deep gluteal syndrome as a cause of posterior hip pain and sciatica-like pain

Deep gluteal syndrome is an increasingly recognized disease entity, caused by compression of the sciatic or pudendal nerve due to non-discogenic pelvic lesions. It includes the piriformis syndrome, the gemelli-obturator internus syndrome, the ischiofemoral impingement syndrome, and the proximal hamstring syndrome. The concept of the deep gluteal syndrome extends our understanding of posterior hip pain due to nerve entrapment beyond the traditional model of the piriformis syndrome. Nevertheless, there has been terminological confusion and the deep gluteal syndrome has often been undiagnosed or mistaken for other conditions. Careful history-taking, a physical examination including provocation tests, an electrodiagnostic study, and imaging are necessary for an accurate diagnosis. After excluding spinal lesions, MRI scans of the pelvis are helpful in diagnosing deep gluteal syndrome and identifying pathological conditions entrapping the nerves. It can be conservatively treated with multidisciplinary treatment including rest, the avoidance of provoking activities, medication, injections, and physiotherapy. Endoscopic or open surgical decompression is recommended in patients with persistent or recurrent symptoms after conservative treatment or in those who may have masses compressing the sciatic nerve. Many physicians remain unfamiliar with this syndrome and there is a lack of relevant literature. This comprehensive review aims to provide the latest information about the epidemiology, aetiology, pathology, clinical features, diagnosis, and treatment. Cite this article: Bone Joint J 2020;102-B(5):556-567.

Case report and review of the potential role of the Type A piriformis muscle in dynamic sciatic nerve entrapment variant of piriformis syndrome

Piriformis syndrome (PS) is an underdiagnosed but common cause of chronic buttock pain and sciatica. Anatomical variants of the piriformis muscle and sciatic nerve have not been thought to be significant in the pathophysiology of PS however, recent description of the piriformis musculotendinous junction has identified a common variant that we believe frequently results in dynamic sciatic nerve entrapment at the infra-piriformis fossa. We performed ultrasound guided low-dose Botulinum Toxin-A (BTX-A) injection to the lower piriformis muscle belly in an elite Australian Rules football player with PS and Type A piriformis muscle to relieve symptomatic sciatic nerve compression. Positive response to targeted BTX-A piriformis muscle injections support the hypothesis that sciatic nerve compression by Type A piriformis muscles may contribute to the pathophysiology of neuropathic PS, along with other functional factors. Sciatic nerve compression due to Type A piriformis at the infra-piriformis fossa has not been described previously and is a potentially common cause of neuropathic PS, especially when combined with other functional factors such as piriformis muscle spasm/hypertrophy and sacroiliac joint counternutation.

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.

A rare cause of non-discogenic sciatica; musculus gemellus inferior: A case report

Herein, we report a 51-year-old female with complaint of right sciatica. According to physical examination, the etiology was suspected as piriformis syndrome. Therefore, piriformis injection was administered and piriformis stretching exercises were recommended.However the complains did not resolve. Magnetic resonance imaging showed hyperintensity of the right inferior musculus gemellus. One of the main causes of extra-spinal sciatica is piriformis syndrome. However, other pelvic muscles anatomically near the sciatic nerve are often overlooked. Magnetic resonance imaging is useful in the differential diagnosis from intractable piriformis syndrome, particularly in cases resistant to treatment.

Ultrasound-Guided Subgluteal Sciatic Nerve Perineural Injection: Report on Safety and Efficacy at a Single Institution

OBJECTIVES

To determine the safety and efficacy of ultrasound (US)-guided subgluteal sciatic nerve injections.

METHODS

A retrospective chart review of US-guided subgluteal sciatic nerve injections at our institution was performed.

RESULTS

Of 221 US-guided subgluteal sciatic nerve injections, 100% achieved technical success, with no postprocedure complications. Sixty-eight percent of patients with follow-up reported symptom relief. Most patients with no relief had suboptimal preprocedure screening.

CONCLUSIONS

With appropriate screening, our technique of US-guided subgluteal sciatic nerve injection is safe and effective.

Piriformis muscle syndrome: A cross-sectional imaging study in 116 patients and evaluation of therapeutic outcome

OBJECTIVES

To increase the clinical awareness of piriformis muscle syndrome (PMs) by reporting cross-sectional imaging findings, the clinical impact of imaging studies and treatment outcome.

METHODS

Within a 10-year-period, 116 patients referred for radiological evaluation of clinically suspected PMs, with excluded lumbar pathology related to symptomatology, were prospectively studied with MRI and/or computed tomography (CT). Piriformis muscle (PM), sciatic nerve (SN), piriformis region and sacroiliac joints were evaluated. PMs was categorised into primary/secondary, according to a reported classification system. Treatment decisions were recorded. Outcome was categorised using a 3-point-scale.

RESULTS

Seventy-four patients (63.8%) exhibited pathologies related to PMs. Primary causes were detected in 12 and secondary in 62 patients. PM enlargement was found in 45.9% of patients, abnormal PM signal intensity/density in 40.5% and sciatic neuritis in 25.7%. Space-occupying lesions represented the most common related pathology. Treatment proved effective in 5/8 patients with primary and 34/51 patients with secondary PMs. In 34 patients, imaging revealed an unknown underlying medical condition and altered treatment planning.

CONCLUSIONS

Secondary PMs aetiologies appear to prevail. In suspected PMs, PM enlargement represented the most common imaging finding and space-occupying lesions the leading cause. Imaging had the potential to alter treatment decisions.

KEY POINTS

• In clinically suspected PMs cross-sectional imaging may reveal variable pathology. • Secondary PMs aetiologies appeared to be more common than primary. • PM enlargement represented the most common imaging finding in clinically suspected PMs. • Space-occupying lesions in the piriformis region represented the leading cause of PMs. • In clinically suspected PMs cross-sectional imaging may alter treatment planning.

Malalignment Syndrome in Runners

More than 80% of runners are out of alignment. The standard back examination should include assessment of pelvic alignment. An awareness of pelvic malalignment and the the malalignment syndrome is essential to allow one to provide proper care of a runner. The 3 most common presentations usually respond to a supervised, progressive treatment program. The validity of any research into the biomechanics of running should be questioned if the study has failed to look at whether pelvic malalignment was present and whether the altered, asymmetrical biomechanical changes attributable to the malalignment itself could have affected the results of the study.

Ultrasound-Guided Injection of Botulinum Toxin Type A for Piriformis Muscle Syndrome: A Case Report and Review of the Literature

Piriformis muscle syndrome (PMS) is caused by prolonged or excessive contraction of the piriformis muscle associated with pain in the buttocks, hips, and lower limbs because of the close proximity to the sciatic nerve. Botulinum toxin type A (BoNT-A) reduces muscle hypertonia as well as muscle contracture and pain inhibiting substance P release and other inflammatory factors. BoNT-A injection technique is important considering the difficult access of the needle for deep location, the small size of the muscle, and the proximity to neurovascular structures. Ultrasound guidance is easy to use and painless and several studies describe its use during BoNT-A administration in PMS. In the present review article, we briefly updated current knowledge regarding the BoNT therapy of PMS, describing also a case report in which this syndrome was treated with an ultrasound-guided injection of incobotulinumtoxin A. Pain reduction with an increase of hip articular range of motion in this patient with PMS confirmed the effectiveness of BoNT-A injection for the management of this syndrome.

Decompression of the sciatic nerve entrapment caused by post-inflammatory scarring

A rare case of chronic pain of entrapment neuropathy of the sciatic nerve successfully relieved by surgical decompression is presented. A 71-year-old male suffered a chronic right buttock pain of duration of 7 years which radiating to the right distal leg and foot. His pain developed gradually over one year after underwenting drainage for the gluteal abscess seven years ago. A cramping buttock and intermittently radiating pain to his right foot on sitting, walking, and voiding did not respond to conventional treatment. An MRI suggested a post-inflammatory adhesion encroaching the proximal course of the sciatic nerve beneath the piriformis as it emerges from the sciatic notch. Upon exploration of the sciatic nerve, a fibrotic tendinous scar beneath the piriformis was found and released proximally to the sciatic notch. His chronic intractable pain was completely relieved within days after the decompression. However, thigh weakness and hypesthesia of the foot did not improve. This case suggest a need for of more prompt investigation and decompression of the chronic sciatic entrapment neuropathy which does not improve clinically or electrically over several months.

Comparison of two stretching methods and optimization of stretching protocol for the piriformis muscle

Piriformis syndrome is an uncommon diagnosis for a non-discogenic form of sciatica whose treatment has traditionally focused on stretching the piriformis muscle (PiM). Conventional stretches include hip flexion, adduction, and external rotation. Using three-dimensional modeling, we quantified the amount of (PiM) elongation resulting from two conventional stretches and we investigated by use of a computational model alternate stretching protocols that would optimize PiM stretching. Seven subjects underwent three CT scans: one supine, one with hip flexion, adduction, then external rotation (ADD stretch), and one with hip flexion, external rotation, then adduction (ExR stretch). Three-dimensional bone models were constructed from the CT scans. PiM elongation during these stretches, femoral neck inclination, femoral head anteversion, and trochanteric anteversion were measured. A computer program was developed to map PiM length over a range of hip joint positions and was validated against the measured scans. ExR and ADD stretches elongated the PiM similarly by approximately 12%. Femoral head and greater trochanter anteversion influenced PiM elongation. Placing the hip joints in 115° of hip flexion, 40° of external rotation and 25° of adduction or 120° of hip flexion, 50° of external rotation and 30° of adduction increased PiM elongation by 30-40% compared to conventional stretches (15.1 and 15.3% increases in PiM muscle length, respectively). ExR and ADD stretches elongate the PiM similarly and therefore may have similar clinical effectiveness. The optimized stretches led to larger increases in PiM length and may be more easily performed by some patients due to increased hip flexion.

The diagnosis and management of Piriformis Syndrome: myths and facts

Piriformis Syndrome (PS) is an uncommon, controversial neuromuscular disorder that is presumed to be a compression neuropathy of the sciatic nerve at the level of the piriformis muscle (PM). The diagnosis is hampered by a lack of agreed upon clinical criteria and a lack of definitive investigations such as imaging or electrodiagnostic testing. Treatment has focused on stretching, physical therapies, local injections, including botulinum toxin, and surgical management. This article explores the various sources of controversy surrounding piriformis syndrome including diagnosis, investigation and management. We conclude with a proposal for diagnostic criteria which include signs and symptoms, imaging, and response to therapeutic injections.

Piriformis syndrome surgery causing severe sciatic nerve injury

Piriformis syndrome is a controversial entrapment neuropathy in which the sciatic nerve is thought to be compressed by the piriformis muscle. Two patients developed severe left sciatic neuropathy after piriformis muscle release. One had a total sciatic nerve lesion, whereas the second had a predominantly high common peroneal nerve lesion. Follow-up studies showed reinnervation of the hamstrings only. We conclude that piriformis muscle surgery may be hazardous and result in devastating sciatic nerve injury.

Piriformis syndrome versus radiculopathy following lumbar artificial disc replacement

STUDY DESIGN

Case series.

OBJECTIVE

To describe the presentation, diagnostic challenges, and treatment of five patients with piriformis syndrome after lumbar artificial disc replacement.

SUMMARY OF BACKGROUND DATA

Until recently, spinal fusion was considered the standard for surgical treatment of severe lumbar degenerative disc disease. However, artificial disc replacement now offers an alternative solution. Piriformis syndrome results from entrapment of the sciatic nerve at the greater sciatic notch, with symptoms of pain and numbness radiating from the buttock to the foot, mimicking radiculopathy.

METHODS

In this case series, we report five patients who developed piriformis at our institution after artificial disc replacement.

RESULTS

Five patients, aged 35 to 46 years, developed some or all of the following symptoms in the affected leg after artificial disc replacement: posterior leg and buttock pain, calf weakness, and toe and ball of foot numbness and tingling. The onset of symptoms ranged from 6 days to 8 months postoperative, and became debilitating over time. Each patient was diagnosed with piriformis syndrome through physical examination. Three of the patients received a piriformis injection and reported 50% to 100% pain relief lasting 1 to 3 weeks. The patients subsequently underwent physical therapy that provided relief of their piriformis syndrome-related pain and enabled them to resume their normal activities.

CONCLUSION

Piriformis syndrome has not previously been described in the literature as a sequela of lumbar artificial disc replacement. Our case series indicates that this complication may be underdiagnosed. Careful consideration after artificial disc replacement is required if the patient presents with buttock, leg or foot pain, and/or numbness. It is important for physicians to recognize the symptoms of piriformis syndrome and to differentiate piriformis syndrome from nerve root compression and irritation or referred pain from spinal structures. Although controversial, the proper diagnosis of piriformis syndrome may have prevented some of these patients from undergoing unnecessary surgical procedures.

What's new in the diagnosis and treatment of peripheral nerve entrapment neuropathies

Entrapment neuropathies can be common conditions with the potential to cause significant disability. Correct diagnosis is essential for proper management. This article is a review of recent developments related to diagnosis and treatment of various common and uncommon nerve entrapment disorders. When combined with classical peripheral nerve examination techniques, innovations in imaging modalities have led to more reliable diagnoses. Moreover, innovations in conservative and surgical techniques have been controversial as to their effects on patient outcome, but randomized controlled trials have provided important information regarding common operative techniques. Treatment strategies for painful peripheral neuropathies are also reviewed.

The clinical features of the piriformis syndrome: a systematic review

Piriformis syndrome, sciatica caused by compression of the sciatic nerve by the piriformis muscle, has been described for over 70 years; yet, it remains controversial. The literature consists mainly of case series and narrative reviews. The objectives of the study were: first, to make the best use of existing evidence to estimate the frequencies of clinical features in patients reported to have PS; second, to identify future research questions. A systematic review was conducted of any study type that reported extractable data relevant to diagnosis. The search included all studies up to 1 March 2008 in four databases: AMED, CINAHL, Embase and Medline. Screening, data extraction and analysis were all performed independently by two reviewers. A total of 55 studies were included: 51 individual and 3 aggregated data studies, and 1 combined study. The most common features found were: buttock pain, external tenderness over the greater sciatic notch, aggravation of the pain through sitting and augmentation of the pain with manoeuvres that increase piriformis muscle tension. Future research could start with comparing the frequencies of these features in sciatica patients with and without disc herniation or spinal stenosis.

PIRIFORMIS SYNDROME

OBJECTIVE

Herein, we provide an unbiased review of piriformis syndrome (PS), a highly controversial syndrome for which no consensus exists regarding diagnostic criteria or pathophysiology.

METHODS

A review of the literature in the English language.

RESULTS

A nonpartisan review of the medical literature pertaining to PS revealed that the existence of this entity remains controversial. There is no definitive proof of its existence despite reported series with large numbers of patients.

CONCLUSION

PS remains a controversial diagnosis for sciatic pain. The debate regarding the clinical significance of PS remains active. Nonetheless, there may be a subset of patients in whom the piriformis muscle is a source of pain. The syndrome should be considered in the differential diagnosis of patients with unilateral lower extremity pain.

Entrapment and compressive neuropathies

Entrapment and compressive neuropathies of the upper and lower extremities are frequently encountered disorders in the office. Certain clinical clues in the history and examination, along with electrodiagnostic testing and imaging studies, often suggest the correct diagnosis. Some of the more common neuropathies are discussed, along with suggestions regarding testing and treatment.

Neurosurgical treatment of perineal neuralgias

Perineal pain is the basis of presentation to different specialities. This pain is still rather unknown and leads the different teams to inappropriate treatments which may fail. For more than twenty years, we have seen these patients in a multidisciplinary consultation. Our anatomical works have provided a detailed knowledge of the nervous supply of the perineum which allowed us to propose the description of an entrapment syndrome of the pudendal nerve. Other disturbances of different origins were highlighted helping colleagues to a better analysis of this enigmatic painful syndrome. Cadaveric studies have been done to guide treatments by blocks and surgery if necessary according to well defined criteria. A randomized prospective study validated the surgery. The retrospective study concluded that two thirds of the patients improved after treatment. New anatomical concepts are leading us to enlarge the field of this type of surgery, with the hope of improving the success rate.

Sciatic neuropathy: case report and discussion of the literature on postoperative sciatic neuropathy and sciatic nerve tumors

Sciatic nerve injury and dysfunction is not an uncommon cause of lower extremity symptoms in a musculoskeletal practice. We present the case of a man who presented with lower extremity weakness, pain, and cramps, and was initially diagnosed at an outside institution with bilateral S1 radiculopathies and recommended for spine surgery. He came to us for a second opinion. Electrodiagnostic testing revealed an isolated sciatic neuropathy and the patient was referred for imaging, which showed a sciatic nerve sheath tumor. Review of the literature on sciatic neuropathies shows that there can be many possible etiologies of sciatic nerve dysfunction, but that hip arthroplasty continues to be the leading risk factor. Sciatic nerve tumors are not commonly described in the literature and their definitive management remains unclear.