Moderator: Mark C. Gebhardt, MD
Thesis Presenter: Julius A. Bishop, MD
Topic: Optimizing Management of Radial nerve Palsy Associated with Humeral Shaft Fractures
Advisor: David C Ring, MD
Discussant: George S. Dyer, MD
The decision to undergo an invasive surgical procedure when faced with
an acute radial nerve palsy associated with a humerus fracture is a difficult
decision between the surgeon and the patient that must carefully weigh the
risks and benefits. Dr. Bishop investigated the determinants of the optimal
management strategy using an expected-value decision analysis. He performed
a systematic review of the literature and studied the probabilities of
potential outcomes after initial observation versus early surgery. Measure of
utility was obtained from 82 subjects, without histories of humerus fractures
or radial nerve palsies, who gave scores for these outcomes in a questionnaire.
Using these data, he constructed a decision tree and performed fold back
analysis to determine optimal treatment. Sensitivity analyses were also used
to determine the effect on decision-making of varying outcome probabilities
and utilities. Dr. Bishop demonstrated that given the outcome probabilities
and utilities studied in this model, observation as the optimal management
of acute radial nerve palsy associated with humerus fracture (value of 8.4 for
observation and 6.7 for early surgery). By varying parameters in sensitivity
analysis, he noted that when the rate of recovery following initial observation
falls below 40% or when the utility value for successful early surgery rises
above 9.4, early surgery is the preferred management strategy. In summary,
Dr. Bishops model delineated that initial observation is the preferred strategy
for optimal management of radial nerve palsy associated with humeral shaft
fractures. Moreover, he noted that in clinical setting where the likelihood of
spontaneous recovery of nerve function is low or when an informed patient
has a strong preference for surgery, early surgery may optimize outcomes.
Dr. Dyer commented that this was a thoroughly planned and executed
project. He found the results to be very real and relevant findings. He pondered
what the outcomes and differences would be if both naive patients and
patients with previous history of injury were used to determine utility.
Thesis Presenter: Jamie Monica, MD
Topic: Correlation of Radiographic Muscle Cross Sectional Area with Glenohumeral Deformity in Children with Brachial Plexus Birth Palsy
Advisor: Peter M Waters, MD
Discussant: George S. Dyer, MD
Muscle imbalance about the shoulder in children with persistent brachial
plexus birth palsy is thought to contribute to glenohumeral joint deformity.
Dr. Monica investigated correlation of glenohumeral joint deformity with
shoulder internal/external rotator cuff muscle cross-sectional areas as well as
clinical scores. He did this by taking a cohort of 74 patients with chronic
neuropathic changes about the shoulder from brachial plexus birth palsy and
dividing them into 5 classified subtypes based on severity of the glenohumeral
joint deformities. In addition to quantifying passive range of motion, Mallet
and Toronto clinical scores and Narakas type, he took cross-sectional measurement
in MRI for pectoralis major (PM), teres minor/infraspinatus (ER)
and subscapularis (SS). Ratios of these different muscle cross-sectional areas
were significantly correlated with glenohumeral deformity type. He showed
that PM/ER values in affected shoulders were significantly higher than PM/
ER values in unaffected shoulders in all deformity types by 30% (p<0.001), SS+PM/ER by 19% (p="0.015)," and SS/ER by 10% (p="0.008)." Moreover, higher PM/ER muscle cross-sectional area ratios indicated more severe deformity types. In contrast, the clinical scores did not correlate with the amount of deformity. In conclusion, Dr. Monica’s study may provide useful information to guide timing and choice of operative intervention in children with muscle imbalance to prevent glenohumeral joint deformity.
Dr. Dyer applauded Dr. Monica for a wonderful project that is simple in
methodology but extremely valuable in potential applications. He questioned
why the clinical scores did not correlate with the severity of the glenohumeral
joint deformity but both he and Dr. Monica reiterated why this would be such
a useful tool to dictate operative treatment.
Thesis Presenter: Josef B. Simon, MD
Topic: Are Normal CT Scans Sufficient to Clear the Cervical Spine?
Advisor: Mitchel B Harris, MD
Discussant: Kevin McGuire, MD
When it comes to clearing the cervical spine, much controversies exist as
to defining the most safe and reliable method. This is especially difficult in a
trauma patient who is rendered unable to participate in a clinical examination.
Recent studies have advocated the sole use of multi-detector CT (MDCT) scan
of the cervical spine to decide if cervical collar immobilization can be discontinued.
Dr. Simon retrospectively reviewed series of trauma patients consecutively
admitted to the Emergency Department between June 2001 and
July 2006 that underwent CT scans of their C-spine after an acute traumatic
event that were used to direct treatment. Out of 708 patients, he identified 91
patients with MDCT scans that were officially recorded as adequate and negative
by an attending ED radiologist who also underwent an MRI during the
same trauma admission period. Retrospectively, two fellowship-trained spine
surgeons re-examined these MDCT scans and deemed 8/91 scans inadequate
scans and three of the adequate scans had fractures that were identified by
both of the spine surgeons; 4 additional fractures and 15 findings suspicious
for instability were identified by at least one of the surgeons. In conclusion,
his data highlighted that reliance on a single imaging modality may lead to
missed diagnosis of cervical spine injuries and emphasized the need for early
involvement of the spine service for radiographic clearance to help identify
occult injuries or suspicious findings necessitating further evaluation.
Dr. Kevin McGuire commended Dr. Simon in tackling such a big project.
He believed that this is critical information for all level I trauma centers. This
study highlights the importance of communication among different providers
in these centers. Moreover, many among the audience agreed that it is absolutely
necessary as orthopaedic surgeons to look at our own films critically
before being biased by radiologists readings