In our latest study, we explored a simple methodological question: does the way we calculate Haversian canal-to-osteon ratios influence our interpretation of bone remodelling activity? As it turns out, the answer is yes. A small difference in analytical approach can produce noticeably different biological conclusions.

Why study Haversian canal-to-osteon ratios?
Bone is constantly being renewed through the activity of Basic Multicellular Units (BMUs), which remove old bone and replace it with new tissue. In cortical bone, this process creates secondary osteons surrounding central Haversian canals. The relative size of these structures provides valuable information about bone remodelling, bone quality, and conditions associated with ageing, disease, biomechanics, and lifestyle. Researchers often use the ratio of Haversian canal area to secondary osteon area as an indicator of the balance between bone resorption and bone formation. Higher ratios generally suggest proportionally larger canal space and less lamellar bone deposition, while lower ratios indicate relatively greater bone formation.

Two common ways to calculate the ratio
We compared two methods commonly used in histological research. Pooling involves measuring all Haversian canals and osteons separately, calculating the mean for each, and then deriving a ratio from those averages. Pairing involves measuring each Haversian canal together with its corresponding osteon, calculating an individual ratio for every remodelling event, and then averaging those ratios. Although both methods aim to describe the same biological process, they are mathematically distinct and do not necessarily yield the same result.

What we did
To investigate this issue, we analysed 551 secondary osteons from femoral midshaft histology slides representing 38 young and middle-aged women from a medieval English skeletal collection. We then calculated Haversian canal-to-osteon ratios using both pooling and pairing approaches and compared the outcomes statistically. 

What we found
Across the sample, the pooling method generally produced lower ratio values than the pairing method. This pattern was observed not only in the full sample but also across age and socioeconomic subgroups. Importantly, the differences between methods were statistically significant and were not explained by the number of osteons measured in each individual. These findings suggest that the choice of averaging technique can directly affect how we interpret bone remodelling. In many cases, pooling implied thicker lamellar bone and therefore greater bone formation during BMU activity, whereas pairing suggested relatively less bone formation per remodelling event.

Why does this matter?
The implications extend beyond statistics. Researchers use these ratios to investigate ageing, osteoporosis, menopause-related bone loss, activity patterns, biomechanics, and socioeconomic influences on skeletal health. If different calculation methods produce different ratio values, they may also lead to different biological interpretations. We found that pooling tends to place greater weight on larger osteons, which can skew the resulting ratio. By contrast, pairing treats each individual remodelling event equally and preserves information at the level of individual BMUs. This makes paired data more biologically informative and more flexible for future analyses that might incorporate additional variables such as osteocyte density or mineralisation patterns. 

Balancing efficiency and precision
There is, however, a practical trade-off. Pooling is generally faster and easier because it requires less data management and fewer calculations. This can be advantageous when dealing with large datasets or when only summary measurements are available. Pairing requires additional effort during data collection and analysis, but it provides greater analytical precision and richer biological information. 

Our take-home message
Our study demonstrates that pooling and pairing are not interchangeable approaches for calculating Haversian canal-to-osteon ratios. While pooling remains useful and efficient, pairing provides a more precise representation of individual bone remodelling events. We therefore encourage researchers to be explicit about which method they use and to consider how that choice may influence biological interpretations and comparisons between studies. Ultimately, methodological transparency is essential if we want bone histology to continue providing reliable insights into health, ageing, and skeletal adaptation in both modern and past populations.

Paper reference here and well done to our post-doc Karen Cooke for leading the study and Honours student Isabella Pearce for collecting part of the data!

Cooke, K. M., Pearce, I., R Claire, A., Louys, J., Mahoney, P., & Miszkiewicz, J. J. (2026). Evaluating Haversian canal-to-osteon ratios for reconstructing bone remodelling activity. Journal of Bone and Mineral Metabolism.

We are very happy to receive acceptance news for our recent mansucript titled "Evaluating Haversian canal-to-osteon ratios for reconstructing bone remodelling activity: balancing precision and efficiency in data collection" in the Journal of Bone and Mineral Metabolism.

In this paper, led by our postdoc Karen Cooke, we test whether simple ratios between Haversian canal size and secondary osteon size can reliably reconstruct bone remodelling activity, and whether these measurements can be streamlined without losing interpretive power. We evaluate how much biological signal is retained when using efficient, lower‑effort histological measurements versus more labour‑intensive ones.

We look forward to sharing our paper once it's published!

We are pleased to announce that our paper on Neanderthal perinatal development has now been accepted for publication. Using high-resolution microcomputed tomography, the study reconstructs fetal bone growth and deciduous tooth development in three Neanderthal juveniles from Sesselfelsgrotte, Germany.

The findings show that Neanderthal prenatal skeletal growth was broadly similar to that of modern humans, while also revealing areas of advanced long bone development and evidence of abnormal dentine mineralisation that may indicate developmental stress or systemic disorder.

Together, the study provides new insights into the evolution of human bone growth, skeletal health, and early development in our closest extinct relatives, Homo neanderthalensis.

Out soon in Royal Society Open Science!

We had a fantastic time in Prague for WCO, presenting our research and seeing the newest research into osteoporosis. Highlights included a keynote by Kirsten Bos, trends in the use of AI in the diagnosis of bone disease and disorders, bone microarchitecture and its impact on BMD, and new methods in the measurement of BMD.

It was an incredible opportunity to share our research into mortality and bone health in a low SES Medieval population on such a massive international stage, and speak to other ECRs presenting their own bone research. 
​
After a conference that provided so much food for thought, in a city as absolutely stunning as Prague, it was difficult to come home again.

The team will be presenting multiple papers at in-person and online conferences all over the globe in the next few months.

First up is the World Congress on Osteoporosis, Osteoarthritis and Musculoskeletal Diseases in Prague (16-19th of April). Our paper is titled "Lower Bone Remodelling and Earlier Mortality in Females: A Historical Example" and was completed in collaboration with Dr Clare McFadden (UQ) and Patrick Mahoney (Uni Kent).

In June, Karen will be presenting a small side project she has been working on with Dr Stacey Ward (ANU) (see our earlier post "On the Road") at the online BeFrail webinar series. The presentation is entitled " Quantification of Periostitis through Confocal Laser Scanning Microscopy and Roughness Analysis". You can register for this talk and others in the BeFrail webinar series here.

And finally, multiple of our lab members have been accepted to present at the Congress of the International Federation of Associations of Anatomists in Melbourne over the 13-16th of August. Our presentations include:

Michelman L, Domett K, Anscomb H, Trollope A, Miszkiewicz J. A Bone to Teach: A novel application of the Oxford Histological Index and collagen birefringence qualitative analysis across three preparation stages of skeletal material from human donors. ​

Cooke KC, Miszkiewicz JJ. Systemic bone remodelling assessment and cancer (differential) diagnosis in ancient human remains. ​

Stewart TJ, Schotsmans EMJ, McFarlane G, Mahoney P, Miszkiewicz JJ.  Intra-skeletal variation in cortical bone microstructure: A comparative study of the rib and femur. 

Stewart TJ, Schotsmans EMJ, McFarlane G, Mahoney P, Miszkiewicz JJ. Assessing variation in bone histological parameters between serial human rib midshaft cross-sections. 

Miszkiewicz JJ.  Persistent challenges with age-at-death estimation using human cortical bone histology. 

Miszkiewicz JJ. Ethical stewardship of ancient bone histology collections. Invited talk for symposium by Aland C, Woods S: Praxis and practice: Stewardship of human tissue originating outside body donor programs. 

We’re excited to share our new study published in the Journal of Anatomy, where we explored how microscopic structures of human bone scale with femoral cross-sectional size. Using midshaft femur microradiographs from 73 individuals in the Melbourne Femur Research Collection, we set out to test whether cortical thickness and biomechanical properties influence the size and density of secondary osteons produced during remodelling.

In our analysis, we measured cortical‑to‑total area (CA/TA), femoral rigidity (Imax/Imin), osteon area, the ratio of Haversian canal to osteon area (H.Ar/On.Ar), and osteon population density across the anterior, posterior, medial and lateral quadrants. We found strong negative correlations between CA/TA and H.Ar/On.Ar in the full sample, in males, and in a subgroup of sedentary but well‑nourished individuals. In these groups, thicker cortices were associated with less porous osteons, meaning smaller Haversian canals relative to surrounding lamellar bone. Notably, this pattern did not appear in females or in other age and lifestyle categories.

Our findings highlight that bone microstructure does not vary independently of bone size. We argue that allometric effects, particularly cortical thickness, should be incorporated into future assessments of bone remodelling and lifestyle reconstruction to avoid confounding histological interpretations.

Link to our paper: ​https://onlinelibrary.wiley.com/doi/10.1111/joa.70143 

A paper Justyna co-authord, led by Chloe Boucher, recently published in the International Journal of Osteoarchaeology, received international attention, with major outlets highlighting its significance for understanding disease, disability, and caregiving in early Philippine societies. 

Medium profiled the study as a window into disease and disability during the Metal Period, emphasising how the skeletal evidence reveals the lived experience of impairment in early Philippine communities. 

PhilStar Global News focused on the discovery as rare evidence of prehistoric caregiving, noting that the individual’s long-term survival with severe impairment suggests strong community support and social care practices 2,000 years ago. 

Archaeology Magazine highlighted the identification of scurvy in the remains, underscoring the study’s contribution to understanding micronutrient deficiency, health stress, and the interplay between diet and disability in ancient Luzon.

Link to paper:
Boucher C, Hussin D, Miszkiewicz JJ, Bolunia MJLA, De Leon AS, Peñalosa AL, Pagulayan PS, Soranio V, Oxenam M, Vlok M. 2026. Nutritional deficiency contributing to physical impairment of an individual in the Metal Period Philippines (~2000-1800BP). International Journal of Osteoarchaeology 

Links to the news sites:
What a 2,000-Year-Old Philippine Skeleton Reveals About Disease and Disability During the Metal Period Medium
What prehistoric bones bare about early Filipino caregiving PhilStar Global News
Scurvy detected on 2,000-year-old remains from the Philippines. Archaeology Magazine

​