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Diaphragmatic Height Index: the New Diagnostic Test for Phrenic Nerve Dysfunction

This study has been completed.
Information provided by (Responsible Party):
Mahidol University Identifier:
First received: October 7, 2011
Last updated: October 10, 2011
Last verified: October 2011

Diaphragmatic contraction is controlled by phrenic nerve which consists of anterior rami of 3rd- 5th cervical nerve roots. Usually, It can't be evaluated from history taking and physical examination. Thus the diaphragmatic elevation on chest radiograph is assumed to identify the phrenic nerve dysfunction. Normally, the right diaphragm is higher than the left side about 1.5 ± 0.9 centimeters or 0.5 ± 0.3 time of vertebral height. Although there are several methods to determine the diaphragmatic elevation from previous studies, the accuracy, reliability, intra and inter-observer variation are problem.

Neurotization is the effective procedure to restore upper extremity function in root avulsion type. Phrenic nerve is one of the common donor nerves which used for this procedure. But sometimes, concomitant injury of this nerve can occur. Therefore, the investigators established "Diaphragmatic height index (DHI)" from chest radiograph to use as the diagnostic test for phrenic nerve dysfunction.

Respiratory Paralysis

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Retrospective
Official Title: Diaphragmatic Height Index: the New Diagnostic Test for Phrenic Nerve Dysfunction

Further study details as provided by Mahidol University:

Primary Outcome Measures:
  • The cut-off point of DHI for diagnosis of phrenic nerve dysfunction [ Time Frame: upto 3 years ]

Enrollment: 245
Study Start Date: September 2009
Study Completion Date: October 2009
Primary Completion Date: October 2009 (Final data collection date for primary outcome measure)
Group A
Brachial plexus injured patients with phrenic nerve dysfunction
Group B
Brachial plexus injured patients without phrenic nerve dysfunction
Group C
Non brachial plexus injured patients


Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
220 brachial plexus injured patients who underwent the neurotization and 80 non-brachial plexus injury patients who underwent the orthopaedic operation were retrospectively reviewed. With using nerve electrical stimulator (Aesculap Nerve Stimulator GN 24, Tuttlingen, Germany), in neurotization procedures, phrenic nerve dysfunction is defined by no any diaphragmatic contraction was observed intraoperatively. The enrolled patients were classified into three main groups: (A) BPI patients with phrenic nerve dysfunction group, (B) BPI patients with normal phrenic nerve function group and (C) non-BPI patients group. In group A and B, we further subgroubed into: (1) for the right and (2) for the left side.

Inclusion Criteria:

  • Brachial plexus injured patients who underwent the neurotization in our institute between 2005-2008
  • Non brachial plexus injured patients who underwent the other orthopedic operation in our institute between April-June 2009

Exclusion Criteria:

  • Concomitant pneumothorax and/or hemothorax
  • Concomitant pulmonary contusion
  • Previous pulmonary disease
  • Chest wall deformity
  • Thoracic or thoracolumbar scoliosis (>10 degrees)
  • Hepatomegaly
  • Incomplete data
  Contacts and Locations
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Please refer to this study by its identifier: NCT01450917

Sponsors and Collaborators
Mahidol University
Principal Investigator: Saichol Wongtrakul, MD Mahidol University
  More Information

Responsible Party: Mahidol University Identifier: NCT01450917     History of Changes
Other Study ID Numbers: Si442/2552(EC2)
Study First Received: October 7, 2011
Last Updated: October 10, 2011

Additional relevant MeSH terms:
Respiratory Paralysis
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Respiratory Insufficiency
Respiration Disorders
Respiratory Tract Diseases processed this record on August 23, 2017