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Strength of Occipital Hair as an Explanation for Pilonidal Sinus Disease Caused by Intruding Hair
Dietrich Doll1, Friederike D Bosche, Verena K Stauffer
11 Department of Procto-Surgery, St. Marienhospital Vechta, Academic Teaching Hospital of the Medizinische Hochschule Hannover, Vechta, Germany 2 Department of Surgery, Luzerner Kantonsspital Sursee, Sursee, Switzerland 3 Institute of Forensic Medicine, Technical University Munich, Munich, Germany 4 Marien-Krankenhaus Bergisch Gladbach, Bergisch Gladbach, Germany 5 Swiss Federal Office of Social Insurance, Bern, Switzerland 6 Department of Anesthesiology and Pain Therapy, Bern University Hospital Inselspital, University of Bern, Bern, Switzerland 7 Department of Surgery, Medical School, University of the Witwatersrand, Johannesburg, Soweto, South Africa.
Background:
Pilonidal sinus disease is thought to be caused by intrusion of hair into healthy skin; loose hair in the intergluteal fold is thought to promote disease. However, compelling evidence to support these postulates is lacking; the cause of pilonidal sinus disease remains uncertain.
Objective:
To determine whether particular properties of hair are associated with susceptibility to pilonidal sinus disease, we compared physical properties of hairs of patients with pilonidal sinus disease with hairs from control subjects who were matched for sex, BMI, and age.
Design:
This was an experimental study with establishment of a mechanical strength test for single hairs to quantify the maximum vertical force that a hair could exert, following tests of strength of occipital, lumbar, and intergluteal hair.
Settings:
Hair from patients with pilonidal sinus disease and matched control subjects were harvested from patients of the St. Marienhospital Vechta Department of Procto-Surgery.
Patients:
A total of 17 adult patients with pilonidal sinus disease and 217 control subjects were included.
Main Outcome Measures:
ANOVA and intraclass and interclass variations of data gained from mechanical strength tests of occipital, lumbar, and intergluteal hair were included.
Results:
Vertical hair strength was significantly greater in patients with pilonidal sinus disease. Occipital hair exhibited 20% greater, glabella sacralis 1.1 times greater, and intergluteal hair 2 times greater strength in patients with pilonidal sinus disease than in matched control subjects (all p = 0.0001). In addition, patients with pilonidal sinus disease presented with significantly more hair at the glabella sacralis and in the intergluteal fold.
Limitations:
The study was limited by its relatively small number of patients from a specific cohort of European patients.
Conclusions:
Occipital hair exhibited considerable vertical strength. Because occipital hair exerted the greatest force and cut hair fragments were found in the pilonidal nest in large quantities, these data suggest that pilonidal sinus disease is promoted by occipital hair. See Video Abstract at http://links.lww.com/DCR/A435.
Insights
Pilonidal sinus disease may be caused by stronger occipital hair penetrating the skin. This study found significantly greater hair strength in patients with pilonidal sinus disease, suggesting a new cause.
Area of Science:
- Dermatology and surgical pathology.
- Biomechanical analysis of biological materials.
Background:
- The etiology of pilonidal sinus disease (PSD) is debated, with hair intrusion being a leading hypothesis.
- Current evidence lacks robust support for the role of hair properties in PSD development.
Purpose of the Study:
- To investigate the association between specific hair physical properties and susceptibility to pilonidal sinus disease.
- To compare hair strength in patients with PSD against matched control subjects.
Main Methods:
- Experimental study employing a mechanical strength test for single hairs.
- Quantification of maximum vertical force exerted by occipital, lumbar, and intergluteal hair.
- Comparison of hair properties between 17 adult PSD patients and 217 control subjects.
Main Results:
- Patients with pilonidal sinus disease exhibited significantly greater vertical hair strength across multiple body regions.
- Occipital hair was 20% stronger, glabella sacralis hair 1.1 times stronger, and intergluteal hair 2 times stronger in PSD patients.
- Increased hair density was observed in the glabella sacralis and intergluteal fold of PSD patients.
Conclusions:
- Occipital hair possesses significant vertical strength, potentially contributing to PSD.
- The findings suggest that strong occipital hair, particularly fragments found in the pilonidal nest, may promote pilonidal sinus disease.
- Further research is warranted, acknowledging the study's limitations including a small, specific patient cohort.
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