The underused hip in ipsilaterally orthotics-dependent children

Testing the Digital Atlas of Ancient Rare Diseases (DAARD) using a new case of Legg-Calvé-Perthes disease from Early Byzantine (500-700 CE) Olympia, Greece

OBJECTIVE

The first case of Legg-Calvé-Perthes disease (LCPD) in Greece is presented. LCPD, a rare disease, is discussed using the Digital Atlas of Ancient Rare Diseases (DAARD), which tests the benefits of the database for diagnosing and contextualizing the new case with 42 archaeological cases of LCPD recorded in the DAARD.

MATERIALS

A 30-40-year-old, probable male individual was found at the archaeological site of Olympia, Greece, dating to 500-700 CE.

METHODS

Biological sex, age-at-death and pathological changes were investigated using macroscopic and osteometric methods. The DAARD provided the typical characteristics of LCPD.

RESULTS

Pathological changes in both hip joints without any other related changes in the skeleton corresponded to the skeletal features of LCPD. The DAARD produced 42 cases of LCPD, most of which from Europe, with a preference for male sex and unilateral involvement of the hip joint.

CONCLUSIONS

The DAARD aids in diagnosing rare diseases and interpreting new cases in the context of already known studies.

SIGNIFICANCE

This study shows that the DAARD has the potential to help researchers move beyond the level of single case studies and create a broader picture of the history of rare diseases.

LIMITATIONS

This paper focuses on the benefits of the DAARD in relation to LCPD but not all rare diseases have been included in the database.

SUGGESTIONS FOR FURTHER RESEARCH

More rare diseases from archaeological contexts should be added to the DAARD to create a base for the interpretation of their history and expand our understanding of rare diseases in the past.

Muscle forces acting on the greater trochanter lead to a dorsal warping of the apophyseal growth plate

The apophyseal growth plate of the greater trochanter, unlike most other growth plates of the human body, exhibits a curved morphology that results in a divergent pattern resembling an open crocodile mouth on plain antero-posterior radiographs. To quantify the angular alignment of the growth plate and to draw conclusions about the function of the muscles surrounding it, we analyzed 57 MRI images of 51 children and adolescents aged 3-17 years and of six adults aged 18-52 years. We measured the angulation of the plate relative to the horizontal plane (AY angle) and the trajectories of the muscles attaching to the greater trochanter of the proximal femur. From anterior to posterior, the AY angle shows a decrease of 33.44°. In the anterior third, the cartilage is angled at a mean of 51.64°, and in the posterior third, the mean angulation is 18.6°. This indicates that the cartilage in the anterior region of the greater trochanteric apophysis is subject to more vertically oriented force vectors compared to the posterior region, as the growth plates align perpendicular to the force vectors acting on them. Combining the measured muscle trajectories with the physiological cross-sectional areas (PCSA) available from the literature revealed that, in addition to the known internal and external lateral traction ligament systems, a third, dorsally located traction ligament system exists that may be responsible for the dorsal deformation of the AY angle.

[The great apophyses: Functional strain and relevance]

BACKGROUND

The structure of apophyses and apophyseal growth plates is not substantially different from those of epiphyses and epiphyseal growth plates. In contrast to epiphyseal growth plates, apophyses and apophyseal growth plates do not contribute to the longitudinal growth of the extremity. They are associated with their adjacent joints, triggering the lengths of their lever arms and influencing their external shape and internal architecture. The formative stimulus on apophyses is given by muscles and tendons inserting at the apophysis or canopying the apophsis.

APOPHYSIS OF THE GREATER TROCHANTER

The apophysis of the greater trochanter significantly contributes to the lever arm length of the hip joint. Its growth activity triggers the neck-shaft angle and finally the centration of the hip joint.

TIBIAL APOPHYSIS

The tibial apophysis interacts with the slope of the proximal tibia and hereby influences the sagittal stability of the knee joint. A damage to the growth plate of the tibial tubercle leads to an anteverted tibial slope and a genu recurvatum difficult to treat.

CALCANEAL APOPHYSIS

The calcaneal apophysis determines the length and position of the calcaneus and herewith influences the torque of the ankle joint. In a nutshell you may regard the apophyses as adjusting screws acting on their adjacent joints and influencing their growth, form and structure.