The glenohumeral joint - a mismatching system? A morphological analysis of the cartilaginous and osseous curvature of the humeral head and the glenoid cavity

Abstract

BackgroundRadial mismatch, glenohumeral conformity ratios and differences between cartilaginous and osseous radii highly depend on the measured plane. The comparison of cartilaginous radii between humeral head and glenoid in different planes provides new information to understand the degree of conformity during abduction of the upper limb.MethodsTo investigate the radii, CT-images in soft-tissue kernel of 9 specimen were analysed using an image visualization software. Statistical analysis of the obtained data was performed using the t-test.ResultsMeasurements of the radii in the glenoid revealed a significantly larger radius for bone than cartilage, whereas for the humeral head the opposite was the case. Highest ratios for cartilage in the transverse plane were found in the inferior and central areas of the joint surface, whereas the smallest ratios were found in the superior area. The radial mismatch varied between 0.1 mm and 13.6 mm, depending on the measured plane.ConclusionsThe results suggest that in abduction, the cartilaginous guidance of the humeral head decreases. This might permit the humeral head an anterior-posterior shifting as well as superior-inferior translation. Surgical reconstruction of the normal glenohumeral relationships necessitates precise information about the glenohumeral morphology to ensure proper sizing and correct placement of prosthetic components and osteochondral allografts.

Glenoid morphology in light of anatomical and reverse total shoulder arthroplasty: a dissection- and 3D-CT-based study in male and female body donors

“…3D-imaging and patient specific instrumentation will have to be based on a profound knowledge of glenoid morphology [8, 61]. We hereby add a new systematic dataset regarding glenoid size, version and inclination angles and scapular distances to the literature.…”

“…Thus, orthopaedic surgeons emphasize a need for better understanding of the glenoid morphology to ensure proper sizing and correct placement of prosthetic components [8]. In particular, the consideration of glenoid size is of high relevance for long-term osseous integration [2, 9, 10].…”

Morphometry of the glenoid cavity and its correlation with selected geometric measurements of the scapula

“…In spite of the glenoid cavity's lack of a deep socket or isometric ligaments, the normal shoulder accurately constrains the humeral head to the center of the glenoid cavity throughout most of the arc of movement [3][4][5][6] . However, its small articulating surface areas correlate with greater probability of dislocation 7,8 . The morphological implication of the glenoid cavity in shoulder stability has been extensively researched 3,9,10 .There have also been various findings about the scapular anthropometry, kinanthroplogy and kinematics [11][12][13] .…”

Avaliação da trilha da glenoide no ombro

“…comparáveis às medidas encontradas nos estudos anatômicos da literatura60,61,[111][112][113][114][115]127 . Como ponto de partida, verificou-se se as superfícies ósseas e cartilaginosas obtidas pelos exames de imagem que poderiam ser representadas como superfícies esféricas, para isso foi feita uma análise de desvio padrão dos seus raios de curvatura utilizados pela técnica de sphere fitting.…”

“…O resultado do raio da face articular da cartilagem da cavidade glenoidalde 27,45mm, apresentado na Tabela 3, foi semelhante ao de Soslowsky et al111 , que encontrou valor de 26,37±2,42mm, o que demonstra ser possível a posterior representação dessas superfícies de forma esférica, com desvios padrão menores que 2%, como defendido por Soslowsky et al111 .Seguiu-se o ajuste da morfologia da escápula, especialmente a cavidade glenoidal, principal região de interesse para o estudo, realizada pelo sphere fitting da fossa glenoidal. De acordo com Zumstein et al112 , a fossa glenoidal A área superficial dessa cartilagem, de 606 mm 2 , e a espessura média de 2,3mm, determinada juntamente com a da cartilagem da cabeça do úmero, apresentam valores condizentes com os da literatura111,113 . Essa escolha foi feita pois os resultados de contato entre as superfícies articulares demonstraram ser mais homogêneos do que sua representação por uma superfície esférica, além da vantagem de representarse de forma mais fidedigna a não conformidade da articulação glenoumeral112,127 .…”