Tonsillar Ectopia

Determining if a Relationship Exists Between Tonsillar Ectopia and Symptom Presentation in Chiari Malformation Patients

Author: Julia R. Saling, B.S.1, Paige Marty, B.S.2, Rebecca Fischbein, Ph.D3, Michelle Chyatte, Dr.PH., MPH4

Author Affiliations:

1 Student Research Fellow, Northeast Ohio Medical University

2 Student Research Fellow, Northeast Ohio Medical University

Research Coordinator and Assistant Professor of Family and Community Medicine, Northeast Ohio Medical University

4 Assistant Professor of Family and Community Medicine, Northeast Ohio Medical University

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Corresponding Author: Julia R. Saling,

Key Words: Chiari Malformation Type I, Tonsillar Ectopia, Symptom Presentation




Chiari Malformation Type I (CM I) is characterized by cerebellar tonsil ectopia and has varying symptomatology . Previous research has shown a relationship between tonsillar dominance and related conditions but few examined association with symptomatology. This study attempts to elucidate a relationship between cerebellar tonsil dominance, age, and symptomatology.


Data from CM I patients were extracted from the Conquer Chiari Patient Registry. Tonsillar dominance was determined using a ratio of right-to-left herniation length. Pearson’s correlation and one-tailed Student’s T-test were used for analysis.


Length of tonsillar descent appears to be negatively correlated to age of onset (r = -0.266; p < 0.001; n = 113) and diagnosis (r = -0.323; p < 0.001; n = 113). No correlation was found between tonsillar dominance and symptom location, nor between tonsillar dominance and symptom severity bilaterally (p > 0.05).  Symptom location and severity ratios appear to be correlated (r = 0.666; p < 0.001). Tonsillar descent length appears to be strongly correlated bilaterally (r = 0.972; p < 0.001; n = 50).

Inconsistency between tonsillar dominance as related to symptomatology suggests a multifactorial contribution to clinical presentation. The inverse relationship between tonsillar herniation length and age of symptom onset and diagnosis suggests herniation length may be an important predictor for clinical outcomes. Further research is needed to elucidate additional contributing factors and tonsillar dominance and symptomatology association.


Published on date: August, 2016


DOI: 10.15404/msrj/08.2016.0007

Citation: Saling et al. Determining if a Relationship Exists Between Tonsillar Ectopia and Symptom Presentation in Chiari Malformation Patients Medical Student Research Journal (2016). doi:10.15404/msrj/08.2016.0007


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Wallis Implant

Pain Relief and Intervertebral Disc Rehydration Following Wallis® Interspinous Device Implantation: a Case Report.

Author: Carter R. Mohnssen, B.S.1,2, Kenneth Pettine, MD2, and Nicole Rittenhouse, MA, CCRC2

Author Affiliations:

1 Creighton University School of Medicine, Omaha, Nebraska, USA.

2 The Spine Institute, Loveland, Colorado, USA.

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Corresponding Author: Carter Mohnssen,

Key Words: intervertebral disc degeneration, case reports, orthopedics, therapeutics, biologics



Introduction: Degeneration of the lumbar motion segment is the primary cause of low back pain in many individuals. Therefore, new minimally invasive treatments are being sought.

Patient Profile: A 47-year old man presented with severe low back pain and radicular symptoms of several years duration. Lumbar MRI revealed severe desiccation, loss of disc height, and an annular tear with right lateral disc protrusion at L4-5.

Interventions/Outcomes: After conservative treatment failed, the patient received a Wallis® interspinous spacer at the affected level. 100% subjective pain relief was obtained at 3 months post-op. Nucleus pulposus rehydration on MRI was observed.

Discussion: Controversy exists over whether disc dehydration is a reliable indicator of low back pain; however, interspinous spacers seem to alter abnormal motion segment’s biomechanics in a way that results in alleviation of low back pain and increased range of motion. With the advent of biologic therapy, this may provide an intriguing minimally invasive treatment modality, although further research is needed.


Published on date: August, 2016


DOI: 10.15404/msrj/04.2016.0006

Citation: Mohnssen, C. Pain relief and intervertebral disc rehydration following Wallis interspinous device implantation: a case report. Medical Student Research Journal (2016). doi: 10.15404/msrj/04.2016.0006


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