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Interpreting pathologies in extant and extinct archosaurs using micro-CT.

Anné J, Garwood RJ, Lowe T, Withers PJ, Manning PL - PeerJ (2015)

Bottom Line: Palaeopathology offers unique insight to the healing strategies of extinct organisms, permitting questions concerning bone physiology to be answered in greater depth.Furthermore, we show that the use of comparative species, both through direct analysis and from the literature, provides key information for diagnosing between vertebrate groups in the typical pathological conditions and physiological processes.Micro-CT imaging, combined with comparative observations of extant species, provides more detailed and reliable interpretation of palaeopathologies.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Earth, Atmospheric and Environmental Sciences, University of Manchester , Manchester , UK.

ABSTRACT
Palaeopathology offers unique insight to the healing strategies of extinct organisms, permitting questions concerning bone physiology to be answered in greater depth. Unfortunately, most palaeopathological studies are confined to external morphological interpretations due to the destructive nature of traditional methods of study. This limits the degree of reliable diagnosis and interpretation possible. X-ray MicroTomography (micro-CT, XMT) provides a non-destructive means of analysing the internal three-dimensional structure of pathologies in both extant and extinct individuals, at higher resolutions than possible with medical scanners. In this study, we present external and internal descriptions of pathologies in extant and extinct archosaurs using XMT. This work demonstrates that the combination of external/internal diagnosis that X-ray microtomography facilitates is crucial when differentiating between pathological conditions. Furthermore, we show that the use of comparative species, both through direct analysis and from the literature, provides key information for diagnosing between vertebrate groups in the typical pathological conditions and physiological processes. Micro-CT imaging, combined with comparative observations of extant species, provides more detailed and reliable interpretation of palaeopathologies. Micro-CT is an increasingly accessible tool, which will provide key insights for correctly interpreting vertebrate pathologies in the future.

No MeSH data available.


Related in: MedlinePlus

E. annectens (BHI 6191) metacarpal; photograph of the specimen in medial-lateral view (A) and XMT slices in medial-lateral (B), dorsal-ventral (C) and transverse (D) views.A fracture probably caused by crushing is seen in the centre of the element, with severe angular misalignment (B). Reactive bone persists throughout the entire metacarpal, with a large rough fracture callus (poorly remodelled). Several necrotic areas are seen throughout the specimen (red arrows B, C). The ends of the metacarpal are almost completely resorbed and replaced with reactive bone (C). Despite the extent of resorption and reactive bone growth, some of the original laminar features can still be seen (red circle D). Scale bar is 1 cm.
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fig-4: E. annectens (BHI 6191) metacarpal; photograph of the specimen in medial-lateral view (A) and XMT slices in medial-lateral (B), dorsal-ventral (C) and transverse (D) views.A fracture probably caused by crushing is seen in the centre of the element, with severe angular misalignment (B). Reactive bone persists throughout the entire metacarpal, with a large rough fracture callus (poorly remodelled). Several necrotic areas are seen throughout the specimen (red arrows B, C). The ends of the metacarpal are almost completely resorbed and replaced with reactive bone (C). Despite the extent of resorption and reactive bone growth, some of the original laminar features can still be seen (red circle D). Scale bar is 1 cm.

Mentions: BHI 6191: The E. annectens metacarpal displays a rough fracture callus (poorly remodelled) that surrounds a badly displaced fracture (Fig. 4). The pathological tissue is very porous and includes several large lesions continuing past the callus and through the metacarpal (Figs. 4B and 4C). The original morphology of the metacarpal can be seen in the transverse view (Fig. 4D) including some laminar histological features, though there is severe angular compaction and displacement (Figs. 4B and 4D). The metacarpal becomes increasingly hard to discriminate from the internal pathological growth moving distally from the apparent fracture plane, with the bone’s ends completely encompassed into the pathological mass (Figs. 4B and 4C). The diagnosis for this pathology is osteomyelitis caused by fracture complications based on the misalignment of the fractured pieces, internal necrosis and islands of ‘normal’ tissue (Rothschild & Martin, 2006; Stacy & Pessier, 2007; Gál, 2008; Waldron, 2009).


Interpreting pathologies in extant and extinct archosaurs using micro-CT.

Anné J, Garwood RJ, Lowe T, Withers PJ, Manning PL - PeerJ (2015)

E. annectens (BHI 6191) metacarpal; photograph of the specimen in medial-lateral view (A) and XMT slices in medial-lateral (B), dorsal-ventral (C) and transverse (D) views.A fracture probably caused by crushing is seen in the centre of the element, with severe angular misalignment (B). Reactive bone persists throughout the entire metacarpal, with a large rough fracture callus (poorly remodelled). Several necrotic areas are seen throughout the specimen (red arrows B, C). The ends of the metacarpal are almost completely resorbed and replaced with reactive bone (C). Despite the extent of resorption and reactive bone growth, some of the original laminar features can still be seen (red circle D). Scale bar is 1 cm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4525691&req=5

fig-4: E. annectens (BHI 6191) metacarpal; photograph of the specimen in medial-lateral view (A) and XMT slices in medial-lateral (B), dorsal-ventral (C) and transverse (D) views.A fracture probably caused by crushing is seen in the centre of the element, with severe angular misalignment (B). Reactive bone persists throughout the entire metacarpal, with a large rough fracture callus (poorly remodelled). Several necrotic areas are seen throughout the specimen (red arrows B, C). The ends of the metacarpal are almost completely resorbed and replaced with reactive bone (C). Despite the extent of resorption and reactive bone growth, some of the original laminar features can still be seen (red circle D). Scale bar is 1 cm.
Mentions: BHI 6191: The E. annectens metacarpal displays a rough fracture callus (poorly remodelled) that surrounds a badly displaced fracture (Fig. 4). The pathological tissue is very porous and includes several large lesions continuing past the callus and through the metacarpal (Figs. 4B and 4C). The original morphology of the metacarpal can be seen in the transverse view (Fig. 4D) including some laminar histological features, though there is severe angular compaction and displacement (Figs. 4B and 4D). The metacarpal becomes increasingly hard to discriminate from the internal pathological growth moving distally from the apparent fracture plane, with the bone’s ends completely encompassed into the pathological mass (Figs. 4B and 4C). The diagnosis for this pathology is osteomyelitis caused by fracture complications based on the misalignment of the fractured pieces, internal necrosis and islands of ‘normal’ tissue (Rothschild & Martin, 2006; Stacy & Pessier, 2007; Gál, 2008; Waldron, 2009).

Bottom Line: Palaeopathology offers unique insight to the healing strategies of extinct organisms, permitting questions concerning bone physiology to be answered in greater depth.Furthermore, we show that the use of comparative species, both through direct analysis and from the literature, provides key information for diagnosing between vertebrate groups in the typical pathological conditions and physiological processes.Micro-CT imaging, combined with comparative observations of extant species, provides more detailed and reliable interpretation of palaeopathologies.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Earth, Atmospheric and Environmental Sciences, University of Manchester , Manchester , UK.

ABSTRACT
Palaeopathology offers unique insight to the healing strategies of extinct organisms, permitting questions concerning bone physiology to be answered in greater depth. Unfortunately, most palaeopathological studies are confined to external morphological interpretations due to the destructive nature of traditional methods of study. This limits the degree of reliable diagnosis and interpretation possible. X-ray MicroTomography (micro-CT, XMT) provides a non-destructive means of analysing the internal three-dimensional structure of pathologies in both extant and extinct individuals, at higher resolutions than possible with medical scanners. In this study, we present external and internal descriptions of pathologies in extant and extinct archosaurs using XMT. This work demonstrates that the combination of external/internal diagnosis that X-ray microtomography facilitates is crucial when differentiating between pathological conditions. Furthermore, we show that the use of comparative species, both through direct analysis and from the literature, provides key information for diagnosing between vertebrate groups in the typical pathological conditions and physiological processes. Micro-CT imaging, combined with comparative observations of extant species, provides more detailed and reliable interpretation of palaeopathologies. Micro-CT is an increasingly accessible tool, which will provide key insights for correctly interpreting vertebrate pathologies in the future.

No MeSH data available.


Related in: MedlinePlus