Correlation between thoracic kyphosis and dry needle length required to reach the pleural space needling the upper trapezius: A cadaveric fluoroscopic assessment.

BACKGROUND: It is unknown whether greater prone thoracic kyphosis increases pneumothorax risk during upper trapezius dry needling. OBJECTIVES: To fluoroscopically assess for a correlation between prone thoracic kyphosis and needle length required to reach the pleural space dry needling the upper trapezius in prone. DESIGN: Cadaveric study. METHODS: Prone thoracic kyphosis was assessed using dual bubble inclinometers. A 30 mm dry needle was inserted into the midsubstance of the upper trapezius perpendicular to the thoracic kyphosis. A single C-arm fluoroscopic image was obtained. This procedure was repeated with 40, 50, and 60 mm needles. Images were independently viewed by a radiologist to make a binary decision (yes vs. no) whether the needle had potentially broached the pleural space. RESULTS: Fifteen cadaveric specimens with a mean age of 74.9 ± 9.7 and mean kyphosis of 21.5° ±7.7 were used. A 30 mm needle never reached the pleural space. The pleural space was potentially broached on one, four and six occasions by the 40, 50, and 60 mm needle respectively. The correlation between needle depth penetration and kyphosis was not significant (r = 0.03, p = 0.93). Longer needles (50 and 60 mm) were significantly (p = 0.0049) more likely to reach the pleural space than shorter needles (30 and 40 mm). CONCLUSION: Thoracic kyphosis was not correlated with needle length required to reach the pleural space. Clinicians may consider selecting shorter needles (<40 mm) to mitigate potential risk while dry needling the upper trapezius in prone.

2015 Young Investigator Award Winner: Cervical Nerve Root Displacement and Strain During Upper Limb Neural Tension Testing: Part 1: A Minimally Invasive Assessment in Unembalmed Cadavers.

STUDY DESIGN: A cross-sectional cadaveric examination of displacement and strain measured at the level of the cervical nerve roots during upper limb neural tension testing (ULNTT) with median nerve bias. OBJECTIVE: To determine the displacement and strain of cervical nerve roots C5-C8 during ULNTT with minimal disruption of surrounding tissues. SUMMARY OF BACKGROUND DATA: Clinical examination of neural pathology involving cervical nerve roots is difficult because of the transient nature of pathologies, such as cervical radiculopathy, entrapment neuropathies, and thoracic outlet syndrome. Cadaveric studies have demonstrated significant displacement and strain in lumbosacral nerve roots during neurodynamic testing of the lower extremity. Examination into the biomechanical behaviors of cervical nerve roots during ULNTT has not been performed. METHODS: Eleven unembalmed cadavers were positioned supine as though undergoing ULNTT. Radiolucent markers were implanted into cervical nerve roots C5-C8. Posteroanterior fluoroscopic images were captured at resting and ULNTT positioning. Images were digitized and displacement and strain were calculated. RESULTS: ULNTT resulted in significant inferolateral displacement (average, 2.16 mm-4.32 mm, P < 0.001) of cervical nerve roots C5-C8. There was a significant difference in inferolateral displacement between the C5 and C6 nerve roots (3.15 mm vs. 4.32 mm, P = 0.009). ULNTT resulted in significant strain (average, 6.80%-11.87%, P < 0.001) of cervical nerve roots C5-C8. There was a significant difference in strain between the C5 and C6 nerve roots (6.60% vs. 11.87%, P = 0.03). CONCLUSION: ULNTT caused significant inferolateral displacement and strain in cervical nerve roots C5-C8. These results provide the mechanical foundation for the use of ULNTT in clinical evaluation of pathology in the cervical region, such as in cervical radiculopathy, entrapment neuropathies, and thoracic outlet syndrome. LEVEL OF EVIDENCE: 2.