The piriformis syndrome

Piriformis syndrome is an often misdiagnosed cause of sciatica, leg, or buttock pain, and disability. The sciatic nerve may be compressed within the buttock by the piriformis muscle, with pain increased by muscular contraction, palpation, or prolonged sitting. A thorough medical history and physical examination are essential to proper diagnosis. Diagnostic testing may be used to differentiate piriformis syndrome from other causes of sciatica, lower extremity weakness, and pain. This article reviews the pathophysiology and management of piriformis syndrome.     

Occurrence of hemophilia in the United States. The Hemophilia Surveillance System Project Investigators

OBJECTIVE: To discuss a case of sciatica associated with lower back pain that originates in a disc. We discuss the use of manipulative therapy as a conservative approach and compare it with other conservative methods and with surgery. CLINICAL FEATURES: The patient suffered from lower back and left leg pain that had increased in severity over a 6-day period. There was decreased sensation in the dorsum of the left foot and toes. Computed tomography demonstrated the presence of a small, contained disc herniation. INTERVENTION AND OUTCOME: The patient was initially treated with ice followed by flexion-distraction therapy. This was used over the course of her first three visits. Once she was in less pain, side posture manipulation was added to her care. Nine treatments were required before she was released from care. CONCLUSION: We need a nonsurgical, conservative approach to treat lower back pain with sciatica as an alternative to and before beginning the more aggressive, and potentially hazardous, surgical treatment. There is some support for the idea that lumbar disc herniation with neurological deficit and radicular pain does not contraindicate the judicious use of manipulation. Although significant questions remain for the evaluation and treatment of lumbar radiculopathy (sciatica) with disc herniations, there is ample evidence to suggest that a course of conservative care, including spinal manipulation, should be completed before surgical consult is considered.     

Dumb-bell shaped tuberculous abscess across the greater sciatic notch compressing both sciatic nerves

We report an instructive case of a 65-year-old man who presented with a dumb-bell shaped tuberculous abscess across the greater sciatic notch bilaterally compressing both sciatic nerves. Clinical symptoms progressed slowly and mimicked lumbar radiculopathy, thus delaying an accurate diagnosis. Anterolateral retroperitoneal and posterolateral gluteal approaches of the greater sciatic notch as well as the acetabulum on both sides were followed in order to provide safe viewing and resection of the abscess. The abscess wall was adherent to the sciatic nerve and surrounding blood vessels. The symptoms completely disappeared after resection of the abscess.     

Spontaneous epidural hematoma as a cause of sciatic pain in a schoolboy

A previously healthy 13-year-old boy began to manifest radiating pain in his left leg after heavy physical exertion during judo training. He also had a sensation of numbness in his left buttock and leg. Initially, the patient was treated conservatively with a clinical diagnosis of disc herniation. However, following 3 months of conservative treatment, there was no relief of pain. Magnetic resonance imaging of the lumbar spine demonstrated an epidural mass causing compression of the dural sac at the L4-L5 disc level. During surgery, the L5 nerve root was found to be severely compressed in the spinal canal because of a chronic epidural hematoma. Following microsurgical removal of this hematoid mass, the patient had a good recovery. Spontaneous epidural hematomas in the lumbar region are rare, and only a few cases presenting with features simulating those caused by a disc herniation have been reported. Our patient represents the first such case described in a child.     

Pelvic fracture with shock-inducing retroperitoneal bleeding and concomitant lower extremity ischemia syndrome: discussion of management exemplified by a case report

BACKGROUND: Initial treatment of severe pelvic fracture consists of appropriate resuscitation and early pelvic reposition and stabilization. Concomitant retroperitoneal arterial bleeding in a hemodynamically unstable patient in combination with lower extremity ischemia make early management decisions very difficult and the mortality rate of this entity of injuries is extremely high. CASE REPORT: We report on a successful treatment of a 36 year old skier, referred in hemorrhagic shock, who had sustained a severely displaced both column fracture of the right acetabulum, an unstable pelvic ring injury on the left and a retroperitoneal bladder rupture. He developed complete ischemia of the right lower extremity. Angiography revealed an obliteration without extravasation of the external iliac artery and allowed treatment of a right superior gluteal artery disruption by embolization. The right lower extremity ischemia was revascularized with a subcutaneous femoro-femoral bypass graft. Delayed internal fixation of the right acetabulum and exploration of the iliac vasculature was done through an ilio-inguinal approach. Simultaneously, the cross-over bypass could be removed. After 18 months, the patient recovered without any ischemic symptoms, but continues with a mixed sciatic nerve lesion. DISCUSSION AND CONCLUSIONS: The combination of severe retroperitoneal arterial bleeding and total ischemia of the lower extremity requires immediate surgical therapy. Direct exploration of the retroperitoneum, however, can be fatal and should be avoided if the iliac vessels are angiographically intact or if a hemorrhage is controllable by an embolization procedure. Extraanatomic temporary revascularization of the lower extremity should be envisaged when a lower leg ischemia due to obliteration or compression of major intrapelvic vessels cannot be directly and immediately treated.     

Anemia and malaria in a Yanomami Amerindian population from the southern Venezuelan Amazon

OBJECTIVE: To review experience with 20 women treated for sciatic hernia between 1993 and 1997. METHODS: Patients with chronic pelvic pain and sciatic hernias, identified retrospectively from chart review, were seen during a 46-month period that covered the surgical experience at our institution and included approximately 1100 cases. The median length of follow-up was 13 months (range 3-36). RESULTS: Sciatic hernia was diagnosed in 20 white women with chronic pelvic pain and was treated using laparoscopy. In 14 cases the hernias were right sided, in five they were left sided, and in one they were bilateral. All sciatic hernias contained the ipsilateral ovary alone or with its fallopian tube. All 20 patients reported symptomatic relief at follow-up. CONCLUSION: Sciatic hernia is a cause of chronic pelvic pain and should be considered in the differential diagnosis.     

Iliopsoas abscess accompanied by epidural abscess--a case report]

A 55-year-old man was admitted to a hospital with pain of the low back as well as the left leg, and fever. He was suspected of suffering from the lumbar disc herniation because of the presence of Lasegue's sign on the first physical examination. Abdominal computed tomography, however, revealed the swelling of the left iliopsoas muscle. Iliopsoas abscess accompanied epidural abscess was confirmed by subsequent magnetic resonance imaging (MRI). Antibiotic therapy was started for the successive 8 days. The fever resolved, but the pain persisted. The abscess extending from the iliopsoas muscle to the epidural space was still seen on the MRI 20 days after the completion of the antibiotic therapy, and he still complained of the pain of his low back and left leg. Therefore, we conducted epidural puncture under fluoroscopic guidance. Approximately 3 ml of pus was aspirated from the epidural space. Then, his complains decreased remarkably. Iliopsoas abscess should be taken into account in case of a patient with pain on the low back and leg and also inflammatory signs such as fever and leucocytosis.     

The function of sensory nerve fibers in lumbar radiculopathy. Use of quantitative sensory testing in the exploration of different populations of nerve fibers and dermatomes

STUDY DESIGN: The function of sensory nerve fibers in patients with lumbar radiculopathy and in control individuals was evaluated using quantitative sensory testing. OBJECTIVES: To investigate the effect of lumbar nerve root compression on different populations of nerve fibers and to explore the function of sensory nerve fibers in neighboring nerve roots not involved in the mechanical compression. BACKGROUND DATA: Results from experimental and clinical studies indicate that chronic compression of lumbar nerve roots affects the large myelinated nerve fibers. The majority of nerve fibers involved in the sensation of pain, however, are small afferent nerve fibers. It is therefore of interest to study the effect of compression on large and small sensory afferent channels. Several authors have elucidated the biochemical interaction between disc tissue and nerve roots. Chemical substances in the epidural space can reach the nerve fibers in nerve roots at the same or neighboring lumbar segments. In this way, fibers not involved in the mechanical compression may be affected. METHODS: The small nerve fibers were studied using tests for thermal thresholds (thermotest), and the large myelinated fibers were studied by vibrametry. Forty-two patients were investigated in the symptomatic and the asymptomatic leg, and the results were compared with those of 21 healthy individuals. RESULTS: The thresholds of cold, warmth, and vibration were significantly increased in the dermatome of the compressed nerve root, indicating that large and small sensory nerve fibers were affected. Further, the thresholds were significantly increased in the neighboring dermatomes in the symptomatic and the asymptomatic leg. CONCLUSION: Large and small sensory afferent nerve fibers are affected in lumbar radiculopathy. The increase in sensation thresholds in the ipsilateral neighboring dermatome and in the dermatomes in the asymptomatic leg indicates that adjacent nerve roots are involved in the pathophysiology of sciatica in patients with lumbar disc herniation.     

Pain drawings in the assessment of nerve root compression: a comparative study with lumbar spine magnetic resonance imaging

STUDY DESIGN: Prospective comparative study of pain drawings with findings on lumbar spine magnetic resonance imaging. OBJECTIVES: To assess the ability of the pain drawing to predict the presence of nerve root compression. SUMMARY OF BACKGROUND DATA: Most research work has concentrated on the ability of the pain drawing to act as a screening method for psychological distress with less work directed at the influence the anatomic abnormality has on the pain drawing. METHODS: One hundred thirty-four consecutive outpatients attending for lumbar magnetic resonance imaging in the investigation of back and leg pain completed pain drawings and psychological testing immediately before the examination. The pain drawing was analyzed by previously reported criteria, and the magnetic resonance imaging was assessed independently for the presence of nerve compression by three radiologists. Multivariate stepwise discriminant analysis was used to identify patients with nerve compression on the basis of their pain drawing. RESULTS: Nerve compression was predicted by numbness in the anterolateral aspect of the foot. There was considerable overlap in the appearances of the pain drawings between patients with and without nerve compression, and the pain drawing correctly classified only 58% of patients with nerve compression. CONCLUSIONS: The pain drawing is not a good predictor of nerve compression on magnetic resonance imaging in a group of patients investigated for back and leg pain. It should be interpreted with caution and in light of the full clinical picture.     

Control of industrial noise and hearing loss at work--are we making progress?

STUDY DESIGN: A case report. OBJECTIVE: To document the occurrence of hematocolpos causing sciatica and leg weakness in an adolescent girl. SUMMARY OF BACKGROUND DATA: Low back pain resulting from hematocolpos has been reported previously but not associated with symptoms of sciatica or neurologic weakness. METHODS: The authors were involved in the care of this patient, and all medical records, radiologic investigations, and related literature were reviewed. RESULTS: After being checked for longstanding symptoms of sciatica and leg weakness, the patient underwent a computed tomographic examination of lumbar spine, which showed a large collection in the pelvis consistent with hematocolpos. Surgical drainage of the collection was associated with complete resolution of her symptoms. CONCLUSIONS: Awareness of hematocolpos as a possible cause for sciatica and neurologic symptoms in the lower limbs may lead to earlier diagnosis and, therefore, reduced morbidity in the investigation of the adolescent girl.     

Can Rinne''s test quantify hearing loss?

Several years after undergoing surgery for a malignant melanoma on his left lower back, a 51 year old man developed intermittently severe pain in his left posterior thigh. Plain X-rays showed no abnormality, but computerized tomography and magnetic resonance imaging scans demonstrated an abnormal soft tissue mass in the left sciatic notch. Although a metastasis from the original melanoma was suspected, exploration of the suspicious area revealed only hypertrophy of the left piriformis muscle. This was due to regular gymnasium exercises designed to selectively build up the musculature of the left lower limb, which the patient had undertaken in the firm belief that it would help to prevent a recurrence of his left-sided melanoma. Complete relief of the unilateral piriformis syndrome was achieved by division of the hypertrophied piriformis muscle, thereby relieving the pressure on the left sciatic nerve as it passed through the greater sciatic foramen.     

Gluteal compartment syndrome: case report

A compartmental syndrome can occur in any space limited by fascia or skin. A case of a gluteal compartment syndrome is reported, apparently from prolonged pressure after a drug overdose. Clinical features were a painful expanding gluteal mass with sciatic nerve dysfunction. Fasciotomy of the tensor fascia lata and the overlying fascia of the gluteus maximus resulted in rapid relief of symptoms.     

High- and low-bar squatting techniques during weight-training

STUDY DESIGN: Tissues in the area of herniated lumbar discs were examined for inflammatory cytokines to elucidate the causes of sciatic pain in lumbar disc herniation. OBJECTIVES: To determine the role of inflammatory cytokines in the stimulation of sciatic pain in lumbar disc herniation. SUMMARY OF BACKGROUND DATA: It is postulated that in addition to mechanical compression of lumbar nerve roots and sensory root ganglia by herniated discs, there is a chemical stimulus to the production of sciatic leg pain. The exact mechanisms of chemical stimulation are not clearly defined. METHODS: During surgery, cases of lumbar disc herniation in 77 patients were classified macroscopically into protrusion, extrusion, and sequestration types. Tissues adjacent to nerve roots at the herniation were excised and analyzed biochemically and immunohistochemically for the presence of inflammatory cytokines and for the production of these cytokines and prostaglandin E2 in vitro. RESULTS: The homogenates of samples were analyzed for interleukin-1 alpha, interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha, and granulocyte-macrophage colony stimulating factor, which were detectable. Most of the cytokine-producing cells were histiocytes, fibroblasts, or endothelial cells in extrusion and sequestration types, and chondrocytes in protrusion type. The secretion of these cytokines and prostaglandin E2 was decreased by the addition of betamethasone. The prostaglandin E2 production was dramatically enhanced by additional interleukin-1 alpha, but decreased by the addition of tumor necrosis factor-alpha. CONCLUSION: The results demonstrate that at the site of lumbar disc herniation, inflammatory cytokines such as interleukin-1 alpha are produced, which increases prostaglandin E2 production. Further studies are required to elucidate the role of inflammatory cytokines in causing sciatic pain.     

Arthrotic sciatica caused by radicular compression of osteophytic origin in the lateral recess. Apropos of 18 cases

The authors report 18 cases of arthrosic sciatica due to toot compression in the lateral recess by posterior corporeal and/or posterior apophyseal osteophytosis. The authors study the clinical and radiological characteristics that may indicate the diagnosis and discuss the different mechanisms by which vertebral arthrosis can lead to radicular compression. When surgery is necessary because of the persistent nature of the sciatica, a broader approach should be undertaken than that required for excision of the disc, in order to explore fully the roots, the multiplicity of possible compression sites being one of the essential characteristics of these cases of arthrosic radiculopathy. Study of the literature and of the series of sciatica patients operated upon by the authors shows that although discal hernia is far from being the most frequent cause of common sciatica, arthrosic compression is a cause that cannot be ignored, especially in aged subjects.     

Extensive malignant schwannoma of the sciatic nerve. Contribution of imaging techniques

The authors reports a case of malignant schwannoma of sciatic nerve. Clinically, this tumor was manifested by a progressive tumefaction of the leg, and moderate pain, without functional signs. The origin of the sciatic nerve has been suspected by computed tomography, because its location, the vascular contacts, and the lesion's extension. Biopsy leads to confirm the nerve tumor, and precised the histologic type: malignant schwannoma. Local, regional and general extension did not premise treatment.     

The role of focal nerve ischemia and Wallerian degeneration in peripheral nerve injury producing hyperesthesia

BACKGROUND: A new model of pain associated with an experimental peripheral mononeuropathy has stimulated interest in mechanisms of pain and their structural correlates in peripheral nerve, the site of the experimental lesion. METHODS: The pathology of the neuropathy was studied and the results correlated with alterations in nerve blood flow and with the behavioral response to heat applied to the foot. The focal neuropathy was created by loosely tying several ligatures around rat sciatic nerve, which produces hyperesthesia in the ligated limb in 3-5 days. The neuropathology was striking with epineurial and endoneurial vascular stasis, edema, and extensive nerve fiber injury in the ligated segment noted at 1 week after ligation. RESULTS: Nerve blood flow was reduced significantly in the ligated segment during the development of the hyperesthesia response, suggesting that changes in nerve blood flow caused by the ligature compression of the epineurial vessels contributes to the nerve fiber injury and pathophysiology of the model. To further test this hypothesis, the epineurial vasculature was removed from 1-cm lengths of rat sciatic nerve, which reduces nerve blood flow by 58%, and by ligation of the ipsilateral femoral artery, which focally reduces nerve blood flow by 70%, and the behavioral response to heating of the paw was evaluated at 1 week. Crush injury was used as a positive control creating Wallerian degeneration without a substantial reduction in nerve blood flow. CONCLUSIONS: The results suggest that ischemia is an important initial pathogenic mechanism in the hyperesthesia associated with the loose ligature pain model, in so far as it produces Wallerian degeneration and axonal injury. Modest degrees of ischemia producing only demyelination did not produce significant hyperesthesia.     

A primary intrapelvic hydatid cyst presenting with foot drop and a gluteal swelling: a case report

A primary hydatid cyst in the pelvis is rare, and usually presents with pressure symptoms affecting the adjacent abdominal organs. We describe such a cyst which protruded through the sciatic notch and presented as a gluteal swelling with a foot drop due to compression of the lumbosacral nerve roots. Surgical excision and postoperative treatment with albendazole for six weeks were effective in controlling the disease and preventing recurrence.     

Thoracic outlet compression syndrome caused by a schwannoma of the C7 nerve root

This is the first report of a schwannoma originating from the C7 nerve root causing thoracic outlet compression syndrome. The patient was a 30-year-old woman with a 3-year history of numbness on the radial side of the left hand, left arm tiredness, nocturnal pain in the left forearm and pain in the left elbow, shoulder and neck. Conservative treatment and previous operations, including carpal tunnel release and first rib resection, provided no relief. A left scalenectomy was performed. During the removal of the anterior scalene muscle, a mass approximately 3 cm long and 1.5 cm in diameter was noted under the anterior scalene muscle involving the C7 nerve root. The tumour was encapsulated and covered with attenuated and stretched nerve fascicles. It was completely excised without disturbing the nerve fascicles. The clinical impression was schwannoma, which was confirmed on pathological examination.     

The gluteal compartment syndrome

The gluteal compartment syndrome is a rare, often unrecognized condition which, left untreated, can lead to renal failure, sepsis, and death. The etiology, physiology, and manifestations are similar to those seen in the more common and readily recognized compartment syndromes of the lower leg and forearm. The large gluteal muscle mass confined by the fascia lata of the thigh and tensor fascia lata can, under the right conditions, produce muscle necrosis, acidosis, elevations of creatinine phosphokinase, and ultimately renal failure. A gluteal compartment syndrome most commonly occurs in individuals with an altered mental status due to drugs or alcohol who remain in one position for an extended period of time. This prolonged compression leads to muscle damage, edema, and a full-blown compartment syndrome. Due to its anatomic location and rarity, diagnosis is missed or delayed, resulting in significant morbidity and possible mortality. The mainstay of treatment consists of fasciotomy and debridement.     

New information concerning pain caused by herniated disk and sciatica. Exposure to disk tissue sensitizes the nerve roots

Sciatica has long been considered to be solely due to mechanical deformation (compression) of a spinal nerve root by herniating disc tissue. However, recent experimental findings have demonstrated that, even in the absence of mechanical insult, nucleus pulposus-related substances may not only induce significant structural and functional injury to the adjacent nerve root, but also sensitise the nerve root, producing pain in the event of subsequent root compression. Although neither the specific mechanisms nor the active nucleus pulposus-related substances causing pain have yet been identified, the recent findings suggest that the future may well bring new pharmacological treatment alternatives for sciatica and disc herniation.