Pressure-Specified Sensory Device versus Electrodiagnostic Testing in Brachial Plexus Upper Trunk Injury

ABSTRACT

Brachial plexus upper trunk injury is associated with winged scapula owing to the close anatomical course of the long thoracic nerve and upper trunk. Needle electromyography is a common diagnostic test for this injury; however, it does not detect injury in most patients with upper trunk damage. The pressure-specified sensory device may be an alternative to needle electromyography. Thirty patients with winged scapula and upper trunk injury were evaluated with needle electromyography (EMG) and pressure-specified sensory device (PSSD) tests. EMG testing of the biceps muscle was compared with PSSD testing of the dorsal hand skin (C6 damage), and EMG testing of the deltoid and spinati muscles was compared with PSSD testing of the deltoid skin (C5 damage). PSSD pressure values were significantly higher on the affected arm. On the basis of published and calculated threshold values the PSSD was found to be significantly more sensitive than EMG. The PSSD tests consistently identified injuries that were not detected by needle EMG tests. These findings provide strong evidence that the PSSD is more effective than needle EMG in the detection of brachial plexus upper trunk injury.

KEYWORDS

Brachial plexus - quantitative sensory testing - pressure-specified sensory device - electromyography - winged scapula

REFERENCES

• 1 Sherman S C, O'Connor M. An unusual cause of shoulder pain: winged scapula.  J Emerg Med. 2005;  28 329-331
• 2 Disa J J, Wang B, Dellon A L. Correction of scapular winging by supraclavicular neurolysis of the long thoracic nerve.  J Reconstr Microsurg. 2001;  17 79-84
• 3 Nath R K, Lyons A B, Bietz G. Microneurolysis and decompression of long thoracic nerve injury are effective in reversing scapular winging: long-term results in 50 cases.  BMC Musculoskelet Disord. 2007;  8 25
• 4 Nath R K, Melcher S E. Rapid recovery of serratus anterior muscle function after microneurolysis of long thoracic nerve injury.  J Brachial Plex Peripher Nerve Inj. 2007;  2 4
• 5 Depalma M J, Pease W S, Johnson E W, Kadyan V. A novel technique for recording from the serratus anterior.  Arch Phys Med Rehabil. 2005;  86 17-20
• 6 Friedenberg S M, Zimprich T, Harper C M. The natural history of long thoracic and spinal accessory neuropathies.  Muscle Nerve. 2002;  25 535-539
• 7 Schwartzman R J, Grothusen J R. Brachial plexus traction injury: quantification of sensory abnormalities.  Pain Med. 2008;  9 950-957
• 8 Howard M, Lee C, Dellon A L. Documentation of brachial plexus compression (in the thoracic inlet) utilizing provocative neurosensory and muscular testing.  J Reconstr Microsurg. 2003;  19 303-312
• 9 Coert J H, Meek M F, Gibeault D, Dellon A L. Documentation of posttraumatic nerve compression in patients with normal electrodiagnostic studies.  J Trauma. 2004;  56 339-344
• 10 Perkins B A, Olaleye D, Bril V. Carpal tunnel syndrome in patients with diabetic polyneuropathy.  Diabetes Care. 2002;  25 565-569
• 11 Brown W F, Dellon A L, Campbell W W. Electrodiagnosis in the management of focal neuropathies: the “WOG” syndrome.  Muscle Nerve. 1994;  17 1336-1342
• 12 Tassler P L, Dellon A L. Correlation of measurements of pressure perception using the pressure-specified sensory device with electrodiagnostic testing.  J Occup Environ Med. 1995;  37 862-866
• 13 Coert J H, Dellon A L. Documenting neuropathy of the lateral femoral cutaneous nerve using the Pressure-Specified Sensory Testing device.  Ann Plast Surg. 2003;  50 373-377
• 14 Siemionow M, Zielinski M, Sari A. Comparison of clinical evaluation and neurosensory testing in the early diagnosis of superimposed entrapment neuropathy in diabetic patients.  Ann Plast Surg. 2006;  57 41-49
• 15 Weber R A, Schuchmann J A, Albers J H, Ortiz J. A prospective blinded evaluation of nerve conduction velocity versus Pressure-Specified Sensory Testing in carpal tunnel syndrome.  Ann Plast Surg. 2000;  45 252-257
• 16 Dellon A L. Management of peripheral nerve problems in the upper and lower extremity using quantitative sensory testing.  Hand Clin. 1999;  15 697-715, x
• 17 Trajman A, Luiz R R. McNemar chi2 test revisited: comparing sensitivity and specificity of diagnostic examinations.  Scand J Clin Lab Invest. 2008;  68 77-80
• 18 Bewick V, Cheek L, Ball J. Statistics review 8: Qualitative data – tests of association.  Crit Care. 2004;  8 46-53