Reproducibility of a peripheral quantitative computed tomography scan protocol to measure the material properties of the second metatarsal

Hormonal Control of Bone Architecture Throughout the Lifespan: Implications for Fracture Prediction and Prevention

BACKGROUND

Skeletal modeling in childhood and adolescence and continuous remodeling throughout the lifespan are designed to adapt to a changing environment and resist external forces and fractures. The flux of sex steroids in men and women, beginning from fetal development and evolving through infancy, childhood, puberty, young adulthood, peri/menopause transition, and postmenopause, is critical for bone size, peak bone mass, and fracture resistance.

OBJECTIVE

This review will highlight how changes in sex steroids throughout the lifespan affect bone cells and the consequence of these changes on bone architecture and strength.

METHODS

Literature review and discussion.

RESULTS

The contributions of estrogen and testosterone on skeletal development have been difficult to study due to the reciprocal and intertwining contributions of one on the other. Although orchiectomy in men renders circulating testosterone absent, circulating estrogen also declines due to testosterone being the substrate for estradiol. The discovery of men with absent estradiol or resistance to estrogen and the study of mouse models led to the understanding that estrogen has a larger direct role in skeletal development and maintenance in men and women. The mechanistic reason for larger bone size in men is incompletely understood but related to indirect effects of testosterone on the skeleton, such as higher muscle mass leading to larger mechanical loading. Declines in sex steroids during menopause in women and androgen deprivation therapies in men have profound and negative effects on the skeleton. Therapies to prevent such bone loss are available, but how such therapies can be tailored based on bone size and architecture remains an area of investigation.

CONCLUSION

In this review, the elegant interplay and contribution of sex steroids on bone architecture in men and women throughout the lifespan is described.

Methods for bone quality assessment in human bone tissue: a systematic review

Background

For biomechanical investigations on bone or bone implants, bone quality represents an important potential bias. Several techniques for assessing bone quality have been described in the literature. This study aims to systematically summarize the methods currently available for assessing bone quality in human bone tissue, and to discuss the advantages and limitations of these techniques.

Methods

A systematic review of the literature was carried out by searching the PubMed and Web of Science databases from January 2000 to April 2021. References will be screened and evaluated for eligibility by two independent reviewers as per PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies must apply to bone quality assessment with imaging techniques, mechanical testing modalities, and compositional characterization. The terms used for the systematic search were: “(bone quality”. Ti,ab.) AND “(human bone specimens)”.

Results

The systematic review identified 502 relevant articles in total. Sixty-eight articles met the inclusion criteria. Among them, forty-seven articles investigated several imaging modalities, including radiography, dual-energy X-ray absorptiometry (DEXA), CT-based techniques, and MRI-based methods. Nineteen articles dealt with mechanical testing approaches, including traditional testing modalities and novel indentation techniques. Nine articles reported the correlation between bone quality and compositional characterization, such as degree of bone mineralization (DBM) and organic composition. A total of 2898 human cadaveric bone specimens were included.

Conclusions

Advanced techniques are playing an increasingly important role due to their multiple advantages, focusing on the assessment of bone morphology and microarchitecture. Non-invasive imaging modalities and mechanical testing techniques, as well as the assessment of bone composition, need to complement each other to provide comprehensive and ideal information on the bone quality of human bone specimens.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03041-4.

Treatment of Fractures of Metatarsal Shaft Using a Cemented K-wire Frame

The purpose of this retrospective study was to report on percutaneous reduction and fixation for the treatment of fractures of metatarsal shaft. Between March 2015 and October 2017, 29 patients (37 fractures of metatarsal shaft) were treated using a cemented Kirschner wire (K-wire) frame. The accuracy of reduction of the fragments was assessed as anatomic (0 to 8 points), good (9 to 11 points), fair (12 to 15 points), or poor (>15 points). The Maryland foot score was used to assess pain and functional outcomes. All fractures were reduced using percutaneous techniques. Anatomic reduction was achieved in 31 metatarsal fractures (84%), and good reduction was achieved in 6 (16%). The average bone healing time was 7 weeks (range, 4 to 16). Pin tract infection was noted in 2 metatarsal bones, which healed with pin site care. The mean cost of the cemented K-wire frame was US$335 (range, $283 to $385) per patient. Based on the Maryland foot score, there were 26 excellent results (90%) and 3 good results (10%). The cemented K-wire frame is a useful external fixator and can be an alternative for treating fractures of metatarsal shaft, especially when open surgeries are a major concern owing to severely damaged soft-tissue envelope. The system is cheap and easy to apply and provides rigid fixation, resulting in good function of the foot.

A Narrative Review of Metatarsal Bone Stress Injury in Athletic Populations: Etiology, Biomechanics, and Management

Metatarsal bone stress injuries (BSIs) are common in athletic populations. BSIs are overuse injuries that result from an accumulation of microdamage that exceeds bone remodeling. Risk for metatarsal BSI is multifactorial and includes factors related to anatomy, biology, and biomechanics. In this article, anatomic factors including foot type, metatarsal length, bone density, bone geometry, and intrinsic muscle strength, which each influence how the foot responds to load, are discussed. Biologic factors such as low energy availability and impaired bone metabolism influence the quality of the bone. Finally, the influence of biomechanical loads to bone such as peak forces, load rates, and loading cycles are reviewed. General management of metatarsal BSI is discussed, including acute care, rehabilitation, treatment of refractory metatarsal BSI, and evaluation of healing/return to sport. Finally, we identify future research priorities and emerging treatments for metatarsal BSI.

Bone density of the calcaneus correlates with radiologic and clinical outcomes after calcaneal fracture fixation

BACKGROUND

This study aimed to determine whether bone density correlates with radiologic and clinical outcomes after screw fixation of displaced intra-articular calcaneal fractures (DIACF) with the sinus tarsi approach.

MATERIALS AND METHODS

We retrospectively evaluated 43 consecutive cases of unilateral DIACF between March 2015 and December 2017. Radiologic evaluations were performed using preoperative, postoperative, and last follow-up calcaneal lateral and axial radiographs. In all patients, preoperative CT scanning of both injured and uninjured calcaneus were performed at one scanning and dual x-ray absorptiometry (DXA) scans were obtained. Hounsfield unit (HU) measurement values were determined by placing an elliptical region of interest confined to the cancellous region of the uninjured calcaneus. Clinical outcomes were assessed at a minimum of 12 months postoperatively using Foot and Ankle Outcome Scores (FAOS).

RESULTS

Mean HU values of the uninjured calcaneus significantly correlated with bone mineral density scores obtained from DXA scans of the lumbar and femur (Spearman ρ = 0.656 - 0.748; p < 0.001 for both). Decreased HU values of the uninjured calcaneus significantly correlated with decreased Böhler's angle and widening of calcaneal width from postoperative to last follow-up. (Pearson r = 0.348, p = 0.022; Pearson r = -0.582, p < 0.001, respectively). Increased HU values of the uninjured calcaneus significantly correlated with improved clinical outcomes in three of five FAOS domains, including activities of daily living, sports, and quality of life (beta = 0.283 - 0.322; p < 0.05 for all).

CONCLUSION

Decreased preoperative bone density significantly correlated with decreased Böhler's angle, widening of calcaneal width, and inferior short-term clinical outcomes after screw fixation of DIACF. By quantifying bone density using HU value in area where DXA cannot be performed, such foot bones, determining whether different fixation methods or systemic treatments can be tailored to bone density could help in optimizing clinical outcomes.

LEVEL OF EVIDENCE

Level III, Retrospective case series.

Detection and quantification of renal fibrosis by computerized tomography

Objectives

Reliable biomarkers for renal fibrosis are needed for clinical care and for research. Existing non-invasive biomarkers are imprecise, which has limited their utility.

Methods

We developed a method to quantify fibrosis by subject size-adjusted CT Hounsfield units. This was accomplished using CT measurements of renal cortex in previously irradiated non-human primates.

Results

Renal cortex mean CT Hounsfield units that were adjusted for body size had a very good direct correlation with renal parenchymal fibrosis, with an area under the curve of 0.93.

Conclusions

This metric is a promising and simple non-invasive biomarker for renal fibrosis.

Ten percent re-dislocation rate 13 years after the arthroscopic Bankart procedure

PURPOSE

The aim of the present study was to determine the long-term outcome after the arthroscopic Bankart procedure, in terms of recurrent instability, shoulder function, glenohumeral arthropathy and patient satisfaction.

METHODS

Patients who underwent the arthroscopic Bankart procedure between January 1999 and the end of December 2005 were invited to complete a set of Patient Reported Outcome Measures (PROMs) and visit the hospital for clinical and radiological assessment. PROMs included the Western Ontario Shoulder Instability Index (WOSI), the Oxford Shoulder Instability Score (OSIS) and additional questions on shoulder instability and patient satisfaction. Clinical assessment included the apprehension test and the Constant-Murley score. The Samilson-Prieto classification was used to assess arthropathy on standard radiographs. The primary outcome was a re-dislocation that needed reduction. Secondary outcomes in terms of recurrent instability included patient-reported subluxation and a positive apprehension test.

RESULTS

Of 104 consecutive patients, 71 patients with a mean follow-up of 13.1 years completed the PROMs, of which 53 patients (55 shoulders) were also available for clinical and radiological assessment. Re-dislocations had occurred in 7 shoulders (9.6%). Subluxations occurred in 23 patients (31.5%) and the apprehension test was positive in 30 (54.5%) of the 55 shoulders examined. Median functional outcomes were 236 for WOSI, 45 for OSIS, and 103 for the normalized Constant-Murley score. Of all 71 patients (73 shoulders), 29 (39.7%) reported being completely satisfied, 33 (45.2%) reported being mostly satisfied and 8 (11%) reported being somewhat satisfied. Glenohumeral arthropathy was observed in 33 (60%) of the shoulders.

CONCLUSION

Despite 10% re-dislocations and frequent other signs of recurrent instability, shoulder function and patient satisfaction at 13 years after arthroscopic Bankart repair were good.

LEVEL OF EVIDENCE

Level IV.

A novel method for estimating nail-tract bone density for intertrochanteric fractures

SUMMARY

A novel method based on voxel-based morphometry was proposed to investigate the average volumetric bone mineral density (vBMD) of femoral head nail tract in patients treated with intramedullary nails-proximal femoral nail antirotation (PFNA) and gamma nail (GN). The results showed that there was no significant difference in average vBMD between the two groups.

BACKGROUND

For unstable intertrochanteric fractures, poor bone quality might be one of the most important causes of cut-out complications in the femoral head during surgical treatment. Bone quality is generally regarded as an equivalent of BMD. Thus, we develop a novel voxel-based morphometry-based method to quantify vBMD of the femoral head nail tract.

METHODS

Automatic calculation of average vBMD of nail tracts requires three main steps. First, we built a standard nail tract in a proximal femur template. Then, we mapped the proximal femur structure of each patient to the template by B-spline and Demons registration so that the anatomical positions of the proximal femur of all patients spatially corresponded to the standard template. Finally, we calculated and visualized the average vBMD distribution of the nail tract of all patients. To verify the feasibility of the method, we enrolled 75 patients (52 women and 23 men) with hip fractures to our study to compare measurements. The root mean square of the standard deviation (RMSSD) was calculated, and the coefficient of variation (CV) of the RMSSD (CV-RMSSD) was used to evaluate the reproducibility of intraoperator and interscan measurements. The Mann-Whitney U test was used to compare the average vBMD of nail tracts for the PFNA and GN.

RESULTS

The CV-RMSSD of intraoperator measurements ranged from 1.0% to 2.0%, and the CV-RMSSD of interscan measurements ranged from 3.6% to 4.5%. There was no significant difference in the average vBMD between patients with PFNAs and those with GNs (p > 0.05).

CONCLUSIONS

The proposed method is reproducible for determining the average vBMD, which may provide a reference index for selection of appropriate intramedullary nails for individual patients. The current choice of intramedullary nail based on the experience of a surgeon may be biased.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

A novel method was proposed to measure the spatial average vBMD of nail tracts, which has good potential to provide a reference index for surgeons to choose appropriate implants.

Reliability of upper-limb diaphyseal mineral and soft-tissue measurements using peripheral Quantitative Computed Tomography (pQCT)

OBJECTIVES

To quantify between-day reliability of upper-body diaphyseal measurements (radius, ulna, humerus) using peripheral Quantitative Computed Tomography (pQCT).

METHODS

Fourteen males (age: 25.8±2.3 years,) underwent repeat pQCT scans (one to two days apart) at mid-shaft ulna (60%), mid-shaft radius (60%) and mid-shaft humerus (50%) cross-sections of the non-dominant limb. Intraclass correlation coefficients (ICC) and coefficients of variation (CV) were determined for musculoskeletal morphology variables.

RESULTS

Reliability was excellent (ICC: 0.76-0.99; CV: 1.3-7.3) at all sites for bone mass, stress-strain index, endocortical and pericortical radius, endocortical volumetric bone mineral density (vBMD), muscle area, total area, non-cortical area, and cortical area. Reliability was good to excellent (ICC: 0.58-0.80; CV: 0.6-3.7) for polar vBMD and mid-cortical vBMD; fair to excellent (ICC: 0.30-0.88; CV: 0.5-8.0) for muscle density and cortical density; and fair to good (ICC: 0.25-0.60; CV: 3.4-7.6) for pericortical vBMD. Average reliability across the three sites was excellent (ICC ≥0.77; CV ≤8.0).

CONCLUSIONS

Overall between-day reliability of pQCT was excellent for the mid-shaft ulna, radius and humerus. pQCT provides a reliable and feasible body composition and skeletal morphology assessment tool for upper limb longitudinal investigations in scientific and clinic settings.

Computed tomography derived bone density measurement in the diabetic foot

Background

The accurate and reliable measurement of foot bone density is challenging and there is currently no gold standard technique. Such measurement is particularly valuable in populations at risk of foot bone pathology such as in those with long term diabetes. With research and development, computed tomography may prove to be a useful tool for this assessment. The aim of this study was to establish the reliability of a novel method of foot bone density measurement in people with diabetes using computed tomography.

Methods

Ten feet in people with diabetes were scanned with computed tomography twice with repositioning. Bone density (in Hounsfield units) was assessed in the trabecular and cortical bone in all tarsals and metatarsals. Reliability was assessed with intra-class correlation coefficients (95% confidence intervals), limits of agreement and standard error of measurement.

Results

The reliability of the trabecular density of most bones was excellent with intra-class correlation coefficients ranging from 0.68 to 0.91. Additionally, cortical bone density showed fair to good reliability at the talus (0.52), calcaneus (0.59), navicular (0.70), cuboid (0.69), intermediate cuneiform (0.46) and first metatarsal (0.61).

Conclusions

The study established the reliability of a practical method of assessing the trabecular and cortical foot bone density using computed tomography scanning. This methodology may be useful in the investigation of foot bone disease occurring in diabetes and its early diagnosis, intervention and assessment of treatment efficacy. Further development of this method is warranted.

Electronic supplementary material

The online version of this article (doi:10.1186/s13047-017-0192-7) contains supplementary material, which is available to authorized users.