DOI: 10.5061/dryad.ghx3ffbxw
title: Data from: A case-control study evaluating CT signs of xiphoid process associated with xiphodynia

description: Objectives：To investigate whether CT signs of the xiphoid process, such as
 xiphisternal angle and evidence of soft tissue compression, are useful for
 diagnosing xiphodynia. Design：A case-control study within a cohort.
 Setting/Participants：Participants included 1560 individuals who visited a
 small urban hospital in Japan for chest or abdominal pain between January
 2021 and September 2023. Those who underwent CT examinations including the
 xiphoid process were selected. Nine individuals diagnosed with xiphodynia
 were assigned to the study group, while 321 individuals diagnosed with
 other causes of pain were assigned to the control group. Interventions：The
 xiphisternal angle, evidence of soft tissue compression anterior to the
 xiphoid process, anatomical features at the tip of the xiphoid process,
 and anatomical morphology of the xiphoid process were compared between the
 two groups. Results：There was no significant difference in the
 xiphisternal angle between the two groups. No significant differences were
 observed in evidence of soft tissue compression anterior to the xiphoid
 process or anatomical features at the tip of the xiphoid process. New
 anatomical signs reveal that in approximately 70% of cases, the xiphoid
 process curves forward and then backward.Xi Conclusions：The xiphoid
 process sternal angle is not useful for diagnosing xiphodynia. The
 curvature of the xiphoid process is frequently observed regardless of the
 presence of xiphodynia.
description: <strong>Population </strong>
   This study targeted patients who
 visited the internal medicine outpatient department of Kameyama Municipal
 Medical Center between January 2021 and September 2023 with complaints of
 chest pain or abdominal pain. Case group were defined as patients
 diagnosed with xiphodynia who underwent CT scans including the xiphoid
 process. Diagnosis of xiphodynia was defined as meeting all of the
 following criteria: (1) presence of chest or upper abdominal pain, (2)
 reproducible tenderness upon palpation of the xiphoid process, (3) absence
 of other conditions more likely than xiphodynia as the cause of pain, and
 (4) improvement of pain with local injection of anesthetic agents onto the
 xiphoid process or xiphoid process excision surgery. Control groups were
 defined as patients who underwent CT scans including the xiphoid process
 and were diagnosed with other conditions than xiphodynia as the cause of
 pain. Patients with unknown causes of pain were excluded from the control
 group.   <strong>Data
 collection</strong>  
 Patient data were accessed for research purposes from
 01/10/2023 to 31/03/2024.　Medical records were reviewed to extract
 demographic information including age, gender, site of pain, and
 underlying cause of pain.  
 <strong>Measurement of CT
 signs</strong>   CT
 examinations were utilized to measure signs of interest. Sagittal images
 were created, incorporating the xiphoid process from the thinnest axial
 section.   The xiphisternal
 angle was measured using a method that we defined due to its absence in
 previous literature. We identified two patterns for measurement: one
 between the xiphoid process and the sternal body angle, and the other
 between the xiphoid process and the base of the xiphoid process.
 Additionally, variations in the xiphoid process, such as bending midway or
 inversion, were considered, leading to the definition and measurement of
 four angles: the xiphoid-sternal body angle (XSBA), xiphoid to xiphoid
 base angle (XXBA), xiphoid tip to sternal body angle (XTSBA), and tip to
 base angle of the xiphoid process (TBAXP), as illustrated in
 Fig2.   The definition of
 the xiphisternal angle.   A:
 A line connecting the midpoint of the cranial end and the midpoint of the
 caudal end of the sternal body.  
 B: A tangent line to the midline of the base of the xiphoid
 process (excluding the xiphisternal joint).
   C: A tangent line to the midline at
 the maximum ventral curvature of the xiphoid process.
   D: A tangent line at the tip of the
 xiphoid process.   XSBA: The
 angle between line A and line C, with line A as the baseline.
   XXBA: The angle between line B and
 line C, with line B as the baseline.  
 XTSBA: The angle between line A and line D, with line A as the
 baseline.   TBAXP: The angle
 between line B and line D, with line B as the baseline.
   Regarding compression signs caused by
 the xiphoid process, we assumed and measured the anterior shift of the
 rectus abdominis (ASRA), anterior shift of the skin surface (ASSS), and
 thinness of the subcutaneous tissue (TST) as useful indicators. As for
 anatomical signs at the tip of the xiphoid process, we measured the
 penetration of the xiphoid tip into the rectus abdominis (PXTRA),
 calcification of the xiphoid tip (CXT), and hypertrophy of the rectus
 abdominis (HRA) in contact with the tip of the xiphoid process. The
 definitions for each sign are as follows:　(1) ASRA: At the most ventral
 projection of the xiphoid process, the rectus abdominis shifts anteriorly.
 (2) ASSS: At the most ventral projection of the xiphoid process, the skin
 surface line shifts anteriorly. (3) TST: Subcutaneous tissue compressed by
 the xiphoid process is thinner than surrounding tissue. (4) PXTRA: The tip
 of the xiphoid process contacts the rectus abdominis, and the tip and
 rectus abdominis are not parallel. (5) CXT: In CT abdominal conditions,
 there is calcification at the tip of the xiphoid process. (6) HRA: At the
 point of contact with the xiphoid process, the rectus abdominis is thicker
 than the surrounding rectus abdominis. For cases with multiple tips of the
 xiphoid process, measurements for each sign were taken at the tip with a
 positive PXTRA. In cases where this criterion was not applicable,
 measurements were taken at the longest tip.
   As additional items for CT signs, we
 recorded the imaging range of the CT, the slice thickness of the original
 CT images, and anatomical features of the xiphoid process (shape, number
 of tips, xiphoid foramen, fractures). Regarding the shape of the xiphoid
 process, forward curvature was denoted as "F", backward
 curvature as "B", and the curvature sequence from the base of
 the xiphoid process was represented (e.g., if the sequence is F→B→F, it is
 labeled as "FBF type"), defining it based on the number and
 direction of curvatures. All observations were assessed by the same
 evaluator.
description: # A case-control study evaluating CT signs of xiphoid process associated
 with xiphodynia
 [https://doi.org/10.5061/dryad.ghx3ffbxw](https://doi.org/10.5061/dryad.ghx3ffbxw) This is a dataset from a case-control study that evaluated CT sings of xiphoid process associated with xiphodynia. Participants included 1560 individuals who visited a small urban hospital in Japan for chest or abdominal pain between January 2021 and September 2023. Those who underwent CT examinations including the xiphoid process were selected. Data collected from the medical records and CT images. CT examinations were utilized to measure signs of interest. Sagittal images were created, incorporating the xiphoid process from the thinnest axial section.  ## Description of the data and file structure 1. Columns on yellow background ・Xiphodynia: 0 means none, 1 means present. ・Age [year] ・Sex: 0 means male, 1 means female. ・Location of pain: 0 means chest, 1 means abdomen, 2 means both locations. ・Pain-causing condition: The disease diagnosed as the cause of the pain. Patients for whom the cause of the pain was not identified were excluded. ・CT scan imaging site: 0 means chest and abdomen, 1 means chest, 2 means abdomen. ・CT slice thickness [mm]: The minimum slice thickness of the CT scan. 2. Columns on red background: The four xiphisternal angles uniquely defined in this study. Defined by the following four baselines. A: A line connecting the midpoint of the cranial end and the midpoint of the caudal end of the sternal body. B: A tangent line to the midline of the base of the xiphoid process (excluding the xiphisternal joint). C: A tangent line to the midline at the maximum ventral curvature of the xiphoid process. D: A tangent line at the tip of the xiphoid process. ・XSBA (xiphoid-sternal body angle) [°]: The angle between line A and line C, with line A as the baseline. ・XXBA (xiphoid to xiphoid base angle) [°]: The angle between line B and line C, with line B as the baseline. ・XTSBA (xiphoid tip to sternal body angle) [°]: The angle between line A and line D, with line A as the baseline. ・TBAXP (tip to base angle of the xiphoid process) [°]: The angle between line B and line D, with line B as the baseline. 3. Columns on green background: Compression signs caused by the xiphoid process and anatomical signs at the tip of the xiphoid process uniquely defined in this study. For cases with multiple tips of the xiphoid process, measurements for each sign were taken at the tip with a positive PXTRA. In cases where this criterion was not applicable, measurements were taken at the longest tip. 0 means none, 1 means present. ・ASRA (anterior shift of the rectus abdominis): At the most ventral projection of the xiphoid process, the rectus abdominis shifts anteriorly. ・ASSS (anterior shift of the skin surface): At the most ventral projection of the xiphoid process, the skin surface line shifts anteriorly. ・TST (thinness of the subcutaneous tissue): Subcutaneous tissue compressed by the xiphoid process is thinner than surrounding tissue. ・PXTRA (penetration of the xiphoid tip into the rectus abdominis): The tip of the xiphoid process contacts the rectus abdominis, and the tip and rectus abdominis are not parallel. ・CXT (calcification of the xiphoid tip): In CT abdominal conditions, there is calcification at the tip of the xiphoid process. ・HRA (hypertrophy of the rectus abdominis): At the point of contact with the xiphoid process, the rectus abdominis is thicker than the surrounding rectus abdominis. 4. Columns on blue background: Anatomical features of the xiphoid process. ・Shape of xiphoid process: Forward curvature was denoted as "F", backward curvature as "B", and the curvature sequence from the base of the xiphoid process was represented (e.g., if the sequence is F→B→F, it is labeled as "FBF type"), defining it based on the number and direction of curvatures. ・Xiphoid length [mm]  ・Number of xiphoid tips (count)  ・Xiphoid foramen (count) ・Xiphoid fractures: 0 means none, 1 means present. missing values：NA ## Code/Software Data compilation was performed using Microsoft Excel®. ## SHARING/ACCESS INFORMATION 1. Licenses/restrictions placed on the data: No copyright - non-commercial use only 2. Links to other publicly accessible locations of the data: None 3. Links/relationships to ancillary data sets: None 4. Was data derived from another source? No A. If yes, list source(s): NA 5. Recommended citation for this dataset: R Ono, K Horibata. Data from: A case-control study evaluating CT signs of xiphoid process associated with xiphodynia. Dryad Digital Repository. [https://datadryad.org/stash/dataset/doi:10.5061/dryad.ghx3ffbxw](https://datadryad.org/stash/dataset/doi:10.5061/dryad.6wwpzgn59) ## Author Information A. Principal Investigator Contact Information Name: Ryosuke Ono Institution: Department of Community Medicine, Kameyama, Mie University School of Medicine Address: 2-174 Edobashi, Tsu City, Mie Prefecture, Japan Email: [rikusan2005@yahoo.co.jp](mailto:rikusan2005@yahoo.co.jp) B. Co-investigator Contact Information Name: Ken Horibata Institution: Department of Community Medicine, Kameyama, Mie University School of Medicine Address: 2-174 Edobashi, Tsu City, Mie Prefecture, Japan