AIM:The objectives were to study the morphology of the foramen magnum in dry skulls and to evaluate its antero-posterior diameter, transverse diameter and the foramen magnum index. MATeRIAL and MeTHods:The foramen magna of 53 dry human cadaver skulls that were obtained from the neuroanatomy laboratory were examined. Different shapes of the foramen magnum were macroscopically noted and classified. The antero-posterior and transverse diameters were measured and the average foraminal index was calculated. ResULTs:The foramen magnum shapes were determined as a round shape in 22.6% of cases, egg shape in 18.9%, tetragonal in 18.9%, oval in 15.1%, irregular in 15.1%, hexagonal in 5.6% and pentagonal in 3.8% of the cases. In 20.7% of skulls, the occipital condyle was observed to protrude into the foramen. The mean antero-posterior and transverse diameter of the foramen magnum was determined as 31 ± 2.4 mm and 25.2 ± 2.4 mm respectively. The average foramen magnum index was 1.2 ± 0.1. CoNCLUsIoN:The present study has determined the various shapes of foramen magnum and its morphometry. The data obtained may be of useful to the neurosurgeon in analyzing the morphological anatomy of craniovertebral junction. The findings are also enlightening for the anthropologists, morphologists and clinical anatomists. BULGULAR:Foramen magnum şekilleri vakaların %22,6'sında yuvarlak, %18,9'unda yumurta şekilli, %18,9'unda tetragonal, %15,1'inde oval, %15,1'inde düzensiz, %5,6'sında ekstragonal ve %3,8'inde pentagonaldi. Kafataslarının %20,7'sinde oksipital kondilin foramene doğru çıkıntı yaptığı gözlendi. Foramen magnumun ortalama anteroposterior ve transvers çapı sırasıyla 31±2,4 mm ve 25,2±2,4 mm olarak belirlendi. Ortalama foramen magnum indeksi 1,2±0,1 bulundu. soNUÇ: Mevcut çalışma foramen magnumun çeşitli şekilleri ve morfometrisini belirlemiştir. Elde edilen veriler nörocerraha kraniyovertebral bileşke morfolojik anatomisini analiz etmek açısından faydalı olabilir. Bulgular ayrıca antropologlar, morfologlar ve klinik anatomistler için faydalıdır.ANAHTAR sÖZCÜKLeR: Foramen magnum, Morfoloji, Morfometri, Şekil, Kafatası

The study provides information on the morphology and topography of nutrient foramina in lower limb long bones. The double foramina were more common in femur and rare in the tibia and fibula. The foramina of the femur and tibia were commonly observed at their upper part, whereas in the fibula they were present on the lower part. This knowledge of the nutrient foramina has to be kept in mind during surgical procedures.

The present study observed that the foramina were more common on the posterior surface and were often multiple, directed toward the acromial end. Knowledge of the localization of nutrient foramina can be useful in certain surgical procedures to preserve circulation. We believe that the data obtained from the present study would be of interest to clinicians who are involved in procedures such as bone grafting, surgical approach for internal fixation and coracoclavicular ligament repair.

Background: Since morphometric data on the upper end of the humerus from Indian anatomical samples are scarce, this study was undertaken with reference to orthopedic surgery. The aim was to determine the length, width and depth of the bicipital groove and to find the incidence of a supratubercular ridge of Meyer in an Indian population. Methods:The study included 104 unpaired dry humeri (48 right side and 56 left) which belonged to the anatomy laboratory of our institution. The length, width and depth of the bicipital groove were measured with a digital vernier caliper. The data were tabulated as mean SD and statistically compared between the right and left sides. Results:The mean length, width and depth of the bicipital groove were 84.6 10.9 mm, 8.5 2.3 mm and 4.4 1.8 mm, respectively, which corresponded to 27.8% of the total length, 32.2% of the transverse width and 17% of the anteroposterior widh of the humerus, respectively. There was no statistically significant difference in these parameters between the left and right sides (p > 0.05). A supratubercular ridge of Meyer was seen in 24 (23.1%) of the humeri. Conclusion:The study determined the morphometric parameters of the bicipital groove in an Indian population. We believe that this study will be an important reference for scientific research, and the details are also important for anthropologists and clinical anatomists. (Chang Gung Med J 2012;35:155-9)