Relationship between the Branching Patterns of the Radial Nerve and Supinator Muscle.

The posterior interosseous nerve (PIN) innervates the posterior compartment muscle of the forearm and is a continuation of the deep branch of the radial nerve. The anatomic descriptions of PIN vary among different authors. This study investigated the distribution patterns of PIN and its relationships to the supinator muscle. This study investigated which nerves innervate the posterior compartment muscles of the forearm, the radial nerve, and the PIN, using 28 nonembalmed limbs. Also, the points where the muscle attaches to the bone were investigated. The measured variables in this study were measured from the most prominent point of the lateral epicondyle of the humerus (LEH) to the most distal point of the radius styloid process. For each specimen, the distance between the above two points was assumed to be 100%. The measurement variables were the attachment area of the supinator and branching points from the radial nerve. The attachment points of the supinator to the radius and ulna were 47.9% ± 3.6% and 31.5% ± 5.2%, respectively, from the LEH. In 67.9% of the specimens, the brachioradialis and extensor carpi radialis longus (ECRL) were innervated by the radial nerve before superficial nerve branching, and the extensor carpi radialis brevis (ECRB) innervated the deep branch of the radial nerve. In 21.4% of the limbs, the nerve innervating the ECRB branched at the same point as the superficial branch of the radial nerve, whereas it branched from the radial nerve in 7.1% of the limbs. In 3.6% of the limbs, the deep branch of the radial nerve branched to innervate the ECRL. PIN was identified as a large branch without divisions in 10.7% and as a deep branch innervating the extensor digitorum in 14.3% of the limbs. The anatomic findings of this study would aid in the diagnosis of PIN syndromes.

Effective zone of botulinum toxin a injections in hallux claw toe syndrome: an anatomical study.

INTRODUCTION: The aim of this study was to determine the anatomical location of the motor points of the flexor hallucis longus (FHL) and brevis (FHB) muscles for an effective motor point block. METHODS: Twenty cadavers were used for this study. For the FHL, we identified the line between the medial and lateral epicondyle of the femur and the line joining the prominent point on the surface of the medial malleolus of the tibia and the lateral malleolus of the fibula. For the FHB, we identified the line between the middle-lowest point of the great toe and the middle-lowest point of the sole of the foot. RESULTS: The dense area of the motor points was located at 40-70% for the FHL and 50-70% for the FHB. CONCLUSION: An injection area of 50-60% on the reference line for the FHL and FHB is suggested.

Anatomic localization of motor entry point of superficial peroneal nerve to peroneus longus and brevis muscles.

This study examined the anatomic location of the motor entry point (MEP) and branching point at the proximal and distal points of the tendon of the peroneal muscle by visual observation. Forty-three fresh legs of 25 adult bodies which had been donated to science were investigated in this study. The mean length of the reference line between the most proximal point of the head of the fibula (PHF) and the most distal point of the malleolus of the fibula (DMF) was 33.4 ± 2.5 cm. The MEPs of the peroneus longus (PL) and peroneus brevis (PB) gathered from 20 to 40% (7.0-13.0 cm) and 40 to 60%, respectively. The branching point where the nerve was divided to innervate the PL and PB was 10% and 28% from the PHF, respectively. These anatomic results suggest appropriate areas where to inject phenol or other agents for a MEP block in the case of a spastic lower extremity as well as guidelines for an electromyography conduction test.

Morphometric trajectory analysis for the C2 crossing laminar screw technique.

This paper reports a morphometric study of the C2 laminae to provide quantitative anatomical data for safe crossing laminar screw placement. A valid trajectory is essential for C2 crossing laminar screw placement. Although several clinical technique notes and modifications to define a safe screw trajectory have been introduced in the recent years, no morphometric analysis has been performed to confirm the accuracy of screw trajectory using this technique. In this study, morphometric analysis was performed on 100 Korean C2 three-dimensional reconstruction CT images. The reconstructive C2 vertebrae from the post-edge of the spinal canal to the spinal process were divided into several zones, 1 mm each. Each zone was chosen as the entry point to imitate a crossing laminar screw (3.5 mm diameter) placement. In each 1-mm zoned trajectory, the screw pass ratio (PR), safe screw angle range (SAR) and maximum screw length (MSL) were measured and compared with the data from the other zoned trajectories. The zone '5-6 mm posterior to the post-edge of the spinal canal' was found to be a more feasible and safer entry point for guiding a crossing laminar screw placement than the other zones because this zone could provide a trajectory with maximal PR (85%), SAR (9.57 +/- 4.36 masculine) and a larger MSL (21.74 +/- 2.44 mm) than the other areas. The recommended safe screw angle in the axial plane is 49.68 +/- 4.94 to 59.19 +/- 4.70 masculine. However, the screw angle can vary considerably according to the individual variance. A preoperative evaluation of the screw trajectory is essential for safe screw placement using this technique.

Isolated pineal region metastasis of small cell lung cancer.

The pineal region is an unusual site for brain metastasis and most metastatic pineal lesions are asymptomatic. Rarely the symptoms of metastatic involvement of the pineal gland precede those of the primary tumor or other metastatic sites. An 83 year-old man presented with gait disturbance and limitation of upward gaze. Brain MRI showed homogeneous enhancement of a solitary mass in the pineal region with obstructive hydrocephalus. A stereotactic biopsy was performed, and small cell carcinoma was diagnosed. A systemic investigation for the primary lesion subsequently revealed small cell carcinoma of the lung. The patient was referred for radiotherapy and chemotherapy. Although rare, metastatic tumor should be considered in the differential diagnosis of pineal region tumors, particularly in elderly patients.

Meningeal chloroma (granulocytic sarcoma) in acute lymphoblastic leukemia mimicking a falx meningioma.

Isolated chloromas (granulocytic sarcomas) are rare tumors. Chloromas are masses composed of immature granulocytic cells. Granulocytic sarcoma occurs primarily in patients with acute myelogenous leukemia and may also arise in patients with other myeloproliferative disorders, but rarely in patients with acute lymphoblastic leukemia (ALL). When dural-based, granulocytic sarcoma may be indistinguishable from meningioma radiologically. We now describe one patient affected by ALL with isolated granulocytic sarcoma mimicking a falx meningioma as initial CNS relapses. These unusual clinical manifestation and radiological finding in ALL should be considered as recurrence of leukemia. Early detection and antileukemic treatment of granulocytic sarcoma are necessarily important for favorable prognosis.

Inhibition of nitric oxide synthase induces increased production of growth-associated protein 43 in the developing retina of the postnatal rat.

We investigated the effects of N(G)-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor, on retinal development in the postnatal rat by immunocytochemistry and immunoblotting using antisera against neuronal nitric oxide synthase (nNOS) or growth-associated protein 43 (GAP-43). An nNOS-immunoreactive band of 155 kDa and a GAP-43-immunoreactive band of 48 kDa were present in the extracts of both control and L-NAME-treated rat retinas. The intensity of the nNOS-immunoreactive band was much weaker in the treated rats, whereas the intensity of the GAP-43-immunoreactive band of 48 kDa was much stronger in the treated rats. Much stronger GAP-43 immunoreactivity was visible in the inner plexiform layer (IPL) of the treated retinas at P10, P14 and P21. Our findings suggest that NO may play an important role in the maturation of the IPL in the developing rat retina.

Chronic granulomatous neuritis in idiopathic trigeminal sensory neuropathy. Report of two cases.

Idiopathic trigeminal sensory neuropathy is a clinically benign disorder in which the main feature is facial numbness limited to the territory of one or more divisions of the trigeminal nerve; the disorder persists for a few weeks to several years. and no underlying disease can be identified. Magnetic resonance (MR) imaging findings are occasionally consistent with a small trigeminal neuroma of the left gasserian ganglion associated with idiopathic trigeminal sensory neuropathy. The authors report on two patients who were treated using a skull base approach in which the gasserian ganglion was exposed and the lesion was removed. The pathological diagnosis was chronic granulomatous neuritis. The authors conclude that, in patients with MR findings suggestive of a small trigeminal neuroma, benign idiopathic trigeminal sensory neuropathy should also be considered in the differential diagnosis. A conservative approach featuring sequential MR imaging studies may avoid an unnecessary surgical exploration.

A case of multiple schwannomas of the trigeminal nerves, acoustic nerves, lower cranial nerves, brachial plexuses and spinal canal: schwannomatosis or neurofibromatosis?

In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis.