Asymmetric midshaft femur remodeling in an adult male with left sided hip joint ankylosis, Metal Period Nagsabaran, Philippines

Abstract

Objective: This study investigated microstructural changes of the right and left midshaft femur in an archaeological individual afflicted with left-sided hip joint ankylosis to assess whether increased cortical porosity was present as a result of leg disuse.

Materials: The individual is a middle-aged adult male excavated from the Metal Period (∼2000 BP) Nagsabaran, Luzon Island, Philippines.

Methods: Following standard examination of femur gross anatomy and differential diagnosis of the hip joint fusion, ∼1 cm thick posterior midshaft femur samples were removed for microstructural examination. Using static histomorphometry, bone multi-cellular unit activity from Haversian canal (vascular pore) density, area, and circularity was reconstructed. Spatial positioning of Haversian canals was mapped using Geographic Information Systems software. Phosphate, carbonate, and carbonate:phosphate ratios were obtained using synchrotron-sourced Fourier transform infrared microspectroscopy.

Results: The left femur had greater cortical pore density, with smaller and rounder vascular canals, in addition to lower matrix levels of phosphate and carbonate, when compared to the right femur.

Conclusions: Our data indicate compromised bone tissue in the left femur, and conform to expected bone functional adaptation paradigms of remodeling responses to pathological and biomechanical changes.

Significance: The preservation of this individual's hip abnormality created a unique opportunity to evaluate intra-skeletal bone health asymmetry, which may help other researchers evaluate the presence of limb disuse in archaeological samples.

Limitations: A lack of lower limb data limits our interpretations to femur remodeling only.

Suggestions for further research: Future research efforts should aim to examine the presence of remodeling changes in all bones of the lower limb.

Layunin: Gamit ang buto ng magkabilang pemur ng isang taong natagpuan sa isang archaeological site na may sakit na ankylosis sa kaliwang balakang, pinag-aralan ang iba't-ibang microstructures galing sa gitnang bahagi o midshaft ng pemur upang malaman kung may makikitang mataas na cortical porosity ang buto dahil hindi ito malimit gamitin.

Gamit: Ang pinag-aaralang buto ay galing sa isang indibidwal na tinatayang middle-age na lalaki na namuhay noong Panahon ng Metal (∼2000 BP) sa Nagsabaran, Cagayan, Republika ng Pilipinas.

Pamamaraan: Matapos ang unang pagkilatis sa femur at ang pagkilala ng sakit sa balakang, kumuha ng ∼1 sentimetro ng buto galing sa midshaft ng pemur upang lalong mapag-aralan ang kanyang microstructure. Gamit ang static histomorphometry, napag-aralan ang mga naiwang bakas ng multi-cellular unit activity ayon sa kapal, laki at pagkakabilog ng Haversian canal (vascular pore). Gumamit din ng Geographic Information Systems (GIS) software upang mapag-aralan ang kaugnayan ng posisyon ng Haversian canal. Panghuli, gumamit din ng synchroton-sourced Fourier transform infrared (sFTIR) microspectroscopy upang makuha ang bilang ng phosphate, carbonate, at carbonate:phosphate ratio.

Resulta: Napag-alaman na ang kaliwang pemur ay mayroong higit na maraming cortical pores, maliit at mabilog na vascular canals, at mababang bilang ng phosphate, carbonate kung ihahambing sa kanang pemur.

Konklusyon: Ayon sa aming datos, ang kaliwang pemur ay umaayon sa mga katangian ng isang butong may sakit. Sumunod din ito sa inaasahang bone functional adaptation paradigms of remodeling ng buto dahil may sakit at hindi nagamit.

Kahalagahan: Dahil maganda ang pagkakalibing ng buto ng balakang, nagkaroon ng pagkakataong makilatis ang kalusugan ng sinaunang-tao sa pamamagitan ng pag-aaral ng kalusugan ng buto. Dagdag pa, makakatulong din ito upang malaman kung ibang mananaliksik ang pag-aaral ng ibang butong hindi nagagamit mula sa archaeological site.

Limitasyon: Dahil walang nakuhang ibang buto mula sa binti at paa, ang pemur lang ang naimbestigahan.

Mungkahi para sa mga susunod na pag-aaral: Kung magkakaroon ng pagkakataon sa susunod, dapat maimbistigahan ang lahat ng buto ng binti (lower limb).

Keywords: Carbonate; Histology; Joint stiffness; Phosphate.