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ligaments. This reduced his pain significantly and allowed him to
return to function.
Discussion:
Interspinous ligament injury is an under recognized eti-
ology of back pain. Cadaveric studies have demonstrated that
interspinous ligaments are the weakest of the spinal ligaments and
are subjected to the greatest strain during flexion and extension of
the spine. The diagnosis is largely clinical as imaging modalities such
as MRI have shown varying reliability. Prolotherapy, or proliferative
therapy, is gaining recognition as a treatment modality for tendin-
opathy as well as ligamentous laxity but its use for the treatment of
interspinous ligament injury is poorly described. Further studies are
warranted to explore the presentation and diagnosis of interspinous
ligament injury and the use of dextrose prolotherapy in its
treatment.
Conclusions:
Physiatrists should recognize interspinous ligament
injury as a potential source of chronic back pain in conjunction with or
separate from other diagnoses, such as degenerative disc disease or
radiculopathy. Prolotherapy injections may be beneficial as both an
adjuvant and primary treatment modality.
Level of Evidence:
Level V
Poster 449:
Resolution of Refractory, Cancer-Related Neuropathic
Pain with Tyrosine Kinase Inhibitor: A Case
Report
Paolo G. Jorge, MD (Loma Linda University Health, Rancho
Cucamonga, CA, United States), Colby Vongchaichinsri, MD,
Scott Strum, MD
Disclosures:
Paolo Jorge: I Have No Relevant Financial Relationships
To Disclose
Case/Program Description:
A 36-year-old man with worsening
chest discomfort was found to have left lung metastatic adeno-
carcinoma with malignant pleural effusion. He underwent a left
pneumonectomy, with partial resection of the left 6th rib, fol-
lowed by Intensity
e
Modulated Radiation for 30 days. Surgical pa-
thology showed Exon 19 EGFR deletion and TP53 mutation. Three
months post-radiation therapy he presented to chronic pain clinic
with burning, electrical, 7/10, neuropathic pain. Intercostal nerve
blocks and a pain regimen consisting of acetaminophen, gaba-
pentin, ibuprofen, oxycodone IR, and oxycodone ER provided only
minimal, temporary relief. CT chest shortly after pain clinic visit
revealed new lesions in the right lung. Afatinib, a tyrosine kinase
inhibitor (TKI), was started by oncology for its antineoplastic
effects.
Setting:
Chronic Pain Clinic.
Results:
At pain clinic follow up 2 months later, neuropathic pain was
completely resolved, with only mild left-sided stiffness and discomfort
rated 1/10. All narcotics and analgesics were self-discontinued prior to
the visit and he reported significant quality of life improvement.
Adverse effects of afatinib included diarrhea and paronychia, both
reportedly tolerable. He was referred to physical therapy and
continued on afatinib with the anticipation of long-term pain relief
before possible resistance.
Discussion:
Chronic, debilitating neuropathic pain is a common
sequela related to cancer that is associated with depression,
decreased function, and poor quality of life. Chest wall pain in the
setting of lung cancer is often refractory to traditional pain regi-
mens. Studies have shown upregulation of protein kinases HER2 and
MAPK, activated by EGFR, in neuropathic pain. Pilot studies, using
TKIs to inhibit EGFR and HER2, have shown clinically significant pain
relief and quality of life improvement in the setting of neuropathic
pain.
Conclusions:
This case demonstrates the efficacy of TKIs in providing
complete resolution of refractory, cancer-related neuropathic pain.
Further studies exploring this novel treatment for neuropathic pain
may be beneficial.
Level of Evidence:
Level V
Poster 450:
Unexpected Motor Responses with Motor Stimulus
Testing during Lumbar Radiofrequency Neurotomy: A
Case Series
Wilson J. Chang, MD MPH (Stanford Medical Center), Lisa Huynh, MD,
Matt Smuck, MD, Ashley S. Maybin, MD, Byron J. Schneider, MD,
FAAPMR
Disclosures:
Wilson Chang: I Have No Relevant Financial Relationships
To Disclose
Case/Program Description:
Three cases of unexpected motor stim-
ulus responses during lumbar radiofrequency neurotomy (RFN) despite
proper electrode placement at the expected location of the L5 dorsal
ramus were identified. All patients underwent bilateral lumbar medial
branch RFN after two successful medial branch blocks. All procedures
were performed by board certified PM&R physicians with fellowship
training in interventional spine and done in accordance with Spine
Intervention Society technique. In each case, proper lead placement
was confirmed at the expected location of the L5 dorsal ramus with
multiple fluoroscopic views. Unexpected muscle contraction of the
ipsilateral lower extremity was observed after routine motor stimu-
lation (2Hz, 0.5-2.0 V). In two cases, RFN was performed once no lower
extremity contractions but only multifidus contractions were observed
after the electrode was withdrawn. In one case, the RFN was not
performed due to a persistent motor response after multiple reposi-
tioning; only L3 and L4 medial branches were completed. Post-pro-
cedure, all cases demonstrated intact lower extremity motor strength
in all myotomes.
Setting:
Two academic outpatient clinic medical centers.
Results:
Two cases had post-procedure follow up at 2-5 weeks. Both
demonstrated intact lower extremity neurological exam and reported
60-70% improvement of their index axial low back pain. One reported
new unilateral radicular pain which resolved after one week. One had
known premorbid radicular pain that presented 2 weeks prior to RFN
and symptoms remained unchanged.
Discussion:
In theory, this unexpected motor response could be due to
anomalous innervations or atypical location of the ventral ramus.
Motor stimulus testing helped demonstrate the proximity of the
electrode to these innervations, ultimately preventing the neurotomy
involving the lower extremities.
Conclusions:
These cases highlight the importance of motor stimula-
tion during lumbar RFN as a safeguard to prevent unintended neuro-
tomy of nerves whose muscles are normally innervated by the L5
ventral ramus nerve.
Level of Evidence:
Level IV
PEDIATRICS POSTER HALL: CASE REPORTS
Poster 451:
Functional Gains After Sirolimus Treatment of
Congenital Lymphovascular Malformations
Jessica R. Pruente, MD (Univ of Colorado SOM, Chicago, IL, United
States), Shubra Mukherjee, MD
Disclosures:
Jessica Pruente: I Have No Relevant Financial Relation-
ships To Disclose
Case/Program Description:
Complex vascular malformations affect
0.8-1% of the general population. These can cause pain, delayed
milestones, and functional deficits in children. Sirolimus is used to
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Abstracts / PM R 9 (2017) S131-S290