Hip and Pelvis Imaging File Formats We Open
Hip and pelvis studies arrive in more shapes than almost any other joint: a coronal proton-density fat-saturated MRI series, a radial oblique stack angled around the femoral neck to inspect the acetabular labrum, an MR arthrogram with contrast, a standing pelvis X-ray series, or an isotropic CT built for 3D acetabular fracture planning. Our free hip viewer reads the DICOM files inside each of those studies directly in your browser, along with ZIP, TAR, and NIfTI packages — none of it is uploaded anywhere.
Archive formats
If your scan came as one big compressed file, drop it directly into the viewer — we unpack it in your browser.
- ZIP — the most common format on hospital CDs and patient-portal downloads
- TAR — common for research datasets
- .tar.gz and .tgz — TAR + GZIP compressed
DICOM transfer syntaxes
The technical format used to encode pixel data inside a DICOM file. Our viewer decodes every common transfer syntax used by clinical scanners.
- Implicit VR Little Endian (1.2.840.10008.1.2)
- Explicit VR Little Endian (1.2.840.10008.1.2.1)
- JPEG Lossless (1.2.840.10008.1.2.4.70)
- JPEG Extended 12-bit (used by i-CAT dental CBCT)
- RLE Lossless
- 8-bit, 12-bit, and 16-bit pixel data
- MONOCHROME1 and MONOCHROME2 photometric interpretations
NIfTI (research / converted scans)
NIfTI (Neuroimaging Informatics Technology Initiative) is the format used by most research and post-processing tools. If you ran your scan through a pipeline like FreeSurfer or fastMRI, you likely have a NIfTI file.
- .nii — uncompressed NIfTI volume
- .nii.gz — GZIP-compressed NIfTI (most common)
How your hip or pelvis study is usually packaged
Radiology departments frequently scan the pelvis once and report on both hips from the same series, so your folder may be labelled “pelvis” even though you were referred for one side. MR arthrograms often bundle a handful of fluoroscopy images from the contrast injection alongside the MRI series in the same export. Hospital CDs use a DICOMDIR index file to organize everything; patient-portal downloads are usually a flat ZIP; and gait-lab or hip-morphology research exports frequently arrive as NIfTI volumes instead of DICOM.
If your surgeon ordered a dedicated MR arthrogram to evaluate a suspected labral tear, expect the export to include the diagnostic MRI series plus a short run of fluoroscopic spot images from the needle placement and contrast injection — both belong in the same folder and the viewer treats each as its own series once loaded. Research cohorts studying acetabular morphology or hip impingement sometimes package a whole batch of subjects as individual NIfTI files rather than per-patient DICOM folders, so check the filename rather than the folder structure if you are working from a dataset export.
Compatibility at a glance
| Format | Opens in viewer | 3D / MPR | Notes |
|---|---|---|---|
| Coronal / sagittal hip MRI (parallel stack) | Yes | Yes (3D + MPR) | Standard slice spacing reconstructs cleanly |
| Radial oblique labral series | Yes | No (angled slices, not a stack) | Viewed slice by slice |
| Large-field-of-view pelvis MRI (both hips) | Yes | Limited (thick slices, coarse volume) | Often 3–4 mm spacing |
| Hip / pelvis CT with 3D reformats | Yes | Yes (3D + MPR) | Isotropic voxels, used for fracture and version planning |
| Standing AP pelvis / frog-leg / Dunn X-ray | Yes | N/A (2D projection) | Used for alpha-angle measurement |
Coronal / sagittal hip MRI
Reconstructs cleanly into 3D and MPR
Radial oblique labral series
Opens, but stays slice-by-slice, not a volume
Large-field pelvis MRI
Coarse 3D due to thicker slice spacing
Hip / pelvis CT
Isotropic voxels, ideal for surgical 3D models
Standing pelvis / Dunn-view X-ray
Flat 2D image, no volume to build
What slice thickness means for a hip 3D model
Whether a hip study reconstructs into a usable 3D model depends almost entirely on how it was acquired. A pelvis CT with isotropic voxels — the kind surgeons request before an acetabular fracture fixation or when measuring femoral version — reformats into any plane and produces a solid volume render. A large-field pelvis MRI shot at 3–4 mm slice spacing to save scan time trades that detail away, so the volume looks blocky. Radial oblique labral stacks are angled around the femoral neck on purpose and were never meant to be reformatted into a second plane at all. A single standing AP pelvis or Dunn-view X-ray has no depth information whatsoever, so it stays a flat image no matter how it is processed. If your only goal is measuring the alpha angle or checking acetabular coverage on a 2D film, that limitation does not matter; it only becomes relevant when a surgeon asks for a printable or navigable 3D model, which needs the CT-grade isotropic data rather than the radiograph or the wide-spacing MRI.
Reading guides for hip and pelvis imaging
When a hip or pelvis file won't open
Two situations come up specifically around the hip: after a total hip or hemiarthroplasty replacement, the metal implant scatters the beam and produces heavy streak artefact on CT and signal loss on MRI — the files still open, the image quality near the implant is simply degraded by the original acquisition. Metal-suppression MRI sequences reduce that artefact at the source but cannot remove it entirely, and our viewer displays whatever the scanner recorded rather than attempting its own correction. Separately, some cropped exports only capture half the pelvis, so if the hip you need is missing entirely, ask for a re-export that includes both sides rather than assuming the viewer dropped it. Encrypted discs and archives split across several volumes are the other two exceptions — a hospital release-of-records request or combining the pieces into a single ZIP resolves both.
Frequently Asked Questions
My pelvis MRI covers both hips in one folder — will it still open?
Yes. A bilateral pelvis study is still just a set of DICOM series, and the viewer groups them by series the same way it would for a single-hip scan. You can page through the left and right hip separately once the series are loaded.
Why won't my radial labral series build a 3D volume?
Radial oblique sequences around the femoral neck are acquired as individual angled slices, not as a parallel stack, so there is no consistent slice spacing to reconstruct into a volume. The viewer displays each radial slice on its own; MPR and 3D rendering need a standard parallel series such as the coronal or sagittal acquisition instead.
Can I view my standing pelvis X-ray next to the hip MRI?
Drop both studies into the viewer and it keeps them as separate series you can switch between — the AP pelvis or Dunn-view X-ray stays a flat 2D image, while the MRI series behaves as usual with windowing and, where the geometry allows, MPR.
How large is a typical hip MRI download?
A single-hip protocol is usually 60–300 MB. A bilateral pelvis MRI or an MR arthrogram with extra fluoroscopy images can run past 500 MB. The viewer handles these fine; just give it a moment to finish decoding before you start scrubbing through slices.
I had a total hip replacement — will the metal artefact break the viewer?
No. The DICOM files still load and display normally; the streaking around the implant is a property of the original acquisition, not something our decoder introduces. 3D rendering across the implant level will look distorted because the source data is distorted there, which is expected and not a loading failure.
The hospital only gave me a disc with a Windows program on it — now what?
Ignore that program. Browse the disc for a folder of numbered files with no extension, or named with .dcm — that is the actual pelvis or hip study. Drop that folder straight into our viewer and it will read the same images the vendor software was built to display.