Innervation of the Trapezius Muscle by the Intraoperative Motor Nerve Conduction Study

OBJECTIVE: The purpose of study was to demonstrate the presence of motor input from the spinal accessory and the branches of the upper cervical plexus. METHOD: Twenty-four patients were studied during modified radical neck dissection. The entire length of the spinal accessory nerve, the contributions from the upper cervical plexus and some cervical plexus branches to run to the trapezius independently were preserved in each of these patients. Compound muscle action potentials were measured to each part of the trapezius muscle on stimulation of the spinal accessory, C2, C3, and C4 nerves. RESULTS: Spinal motor nerve evoked responses were obtained from all 24 patients in the upper, middle, and lower trapezius. C2 contributions were seen in 2 out of 24 patients, but were in no patient supplying all three parts of the muscle. C3 contributions were seen in 11 out of 24 patients, but C3 nerve supplied all three parts of the muscle in 8. C4 contributions were seen in 20 out of 24 patients, supplying all three parts of the muscle in 16. CONCLUSION: This study demonstrated that the spinal accessory nerve provided the most important and consistent motor input to the trapezius muscle. Although C2, C3, and C4 provided motor input to the trapezius muscle, they were not consistently present and if present, did not consistently innervate all three parts of the trapezius. Compared with other studies, it was interesting to note that C4 gave more consistent motor input to the trapezius than other cervical branches.

Alteration of Sensory Nerve Action Potentials According to the Interelectrode Separation

OBJECTIVE: Distance between the active and reference electrodes can affect the waveform configuration and amplitude of sensory nerve action potential (SNAP). This study was purposed to determine the change of SNAP parameters with varying interelectrode distance. METHOD: Median sensory nerve conduction study was performed in the middle finger of 40 young healthy subjects by antidromic method. To ensure firm contact with skin, strip adhesive electrode was used for recording responses. The active electrode was fixed on 1 cm distal to the proximal flexion crease of middle finger and interelectrode separation was increased from 1 to 5 cm by 1.0 cm increments. Bar electrode was fixed 14 cm proximal from active electrode for stimulation in the wrist area. RESULTS: As the interelectrode distance increased from 1 cm to 5 cm, onset latency remained unchanged. The peak latency increased with increasing the distance up to 3 cm but didn't change beyond 3 cm (1 cm: 2.89 0.89 msec, 2 cm: 2.97 0.89 msec, 3 cm: 3.02 0.19 msec, 4 cm: 3.02 0.19 msec, 5 cm: 3.02 0.20 msec). Base-to-peak amplitude significantly increased only up to 3 cm (1 cm: 30.3 6.7 microvolt, 2 cm: 43.7 8.6 microvolt, 3 cm: 50.8 10.4 microvolt, 4 cm: 51.1 10.9 microvolt, 5c m: 51.3 11.4 microvolt) but peak-to-peak amplitude sequentially increased to 5 cm (1 cm: 49.6 12.1 microvolt, 2 cm: 72.8 14.4 microvolt, 3 cm: 83.6 19.4 microvolt, 4 cm: 91.3 22.5 microvolt, 5 cm: 93.4 23.9 microvolt)(p<.05). CONCLUSION: This study showed that changing interelectrode distance altered some parameters of SNAP, especially the peak-to peak amplitude.

The Relation between Nocturnal Polyuria and Diurnal Variation of the ADH in Patients with Cervical Cord Injury

OBJECTIVE: It was reported that nocturnal polyuria in cervical cord injured patients may be due to attenuation of diurnal variation of antidiuretic hormone (ADH) level. However, it has been unclear whether the attenuation of diurnal variation of ADH level caused nocturnal polyuria and bladder overdistension. To improve the management of neurogenic bladder with overdistension during the night, we investigated whether the attenuation of diurnal variation of ADH level is the cause of nocturnal polyuria or bladder overdistens-ion in patients with cervical cord injury. METHOD: The subjects consisted of 17 patients with cervical cord injury. The age distribution ranged from 31 to 63 years with an average of 41.5 years. The duration of illness ranged from 5 months to 4 years. Oral intake was restricted below 2,000 ml per day. We measured urine volume and urine osmolarity during the day (8 AM~8 PM) and night period (8 PM~8 AM) and the level of plasma ADH and serum osmolarity at 2 PM and 2 AM. RESULTS: Plasma ADH level was 0.81+/-0.51 pg/ml during the day and 1.04+/-0.65 pg/ml during the night (p=0.17). Urine volume was 1050+/-410 ml during the day and 970+/-550 ml during the night (p=0.92). The average of urine osmolarity was 450.4+/-182.8 mosm during the day and 558.4+/-359 mosm during the night (p=0.25). The average of serum osmolarity was 292.4+/-14.5 mosm during the day and 290.4+/-9.3 mosm during the night (p=0.53). CONCLUSION: This study showed that there was no significant difference in each parameter for two periods and urine volume was not increased in spite of attenuation of diurnal variation of ADH level. Therefore this indicated that attenuation of diurnal varia-tion of ADH was less likely responsible for nocturnal polyuria in patients with cervical cord injury.

A Clinical Study of the Ocular Injuries

The 522 ocular injuries among the 23,249 out and in patients who visited to Dept. of Ophthalmology from 1 Jan., 1980 to 31 July, 1986 were clinically evaluated. 1. The incidence of ocular injuries was 2.2% of all patients. 2. The incidence was more common in male (82.8%) and in the age of second and third decade(57.9%). 3. The ocular injuries were brought regardless of the season. 4. Small iron particles were the most common causative agent and the majority of ocular injuries. 5. Perforating injury was the most common nature of ocular injuries. 6. Primary operations included the sutures of cornea or sclera(49.7%), repair of lid(28.7%), or enucleation or evisceration(7.4%), and secondary operations included most commonly cataract operations, and others. 7. The final visual acuity of 20.7% was 0.1 or less, and 57.1 % was 0.9 or more.

A Case of Intraorbital Meningioma

A clinically rare case of recurrent meningioma of the orbit of 30 years old male is reported. The right eye invaded with fibroblastic meningioma was enucleated in association of resection of tumor mass ten years ago. The second surgery of socket reconstruction for the palpebral and conjunctival atrophy was performed eight years later. An experience of orbital exenteration to a complete removal of walnut sized firm and palpable mass recurred in the orbital socket with successful result after the histo-pathological examination was described.