Anatomical Profile and Morphometric Evaluation of Human Sacral Hiatus in North Indians

Successful caudal epidural block (CEB) for various gynaecological and orthopaedic procedures requires an elaborate knowledge of anatomical profile of sacral hiatus. Varied morphology of sacral hiatus is likely to influence the success rate of CEB. Scanty literature is available on the morphometry of sacral hiatus in North Indian subjects. Therefore, sacral hiatus of 60 North Indian human sacra were evaluated using Vernier calipers. Sexing of the sacra was done by calculating the sacral index. Following parameters of sacral hiatus were observed and recorded: a) Shape, b) Level of apex, c) Maximum distance between the sacral cornua, d) Length of the sacral hiatus i.e. from its apex to midpoint of its base, e) Antero-Posterior diameter at the apex of sacral hiatus. The data obtained was analyzed using SPSS software (version 18). Various shapes of sacral hiatus were observed. It was irregularly shaped in both the sexes though inverted U shaped sacral hiatus was also seen frequently in females. In males, the apex of sacral hiatus was commonly seen at the level of spinous process of 3rd sacral vertebra in males and below the level of spinous process of 4th sacral vertebra in females. The mean distance between the sacral cornua was 1.1cm : 1.2cm in males and females, respectively. Mean length of the sacral hiatus was 2cm in both sexes. Antero-posterior depth at the apex the sacral hiatus was 6mm in both the genders. The dimensions of sacral hiatus obtained in this study were inconsistent with earlier studies. Knowledge of these dimensions may help the clinicians in precisely locating sacral hiatus for successful CEB in North Indians.

Clinical implications of additional heads of biceps brachii muscle

Biceps brachii is a superficial muscle of the flexor compartment of arm. It is a strong flexor and a supinator of forearm. It is one of the most variable muscles in terms of number of its heads of origin, so the present study proposes to dissect North Indian cadavers to see the frequency of occurrence of more than two heads of biceps brachii and discusses its clinical implications. To determine the prevalence of accessory heads of biceps brachii, their inervation and any anomalous course of neurovascular bundle in the front of arm. Number of heads of biceps brachii muscle were studied in 77 adult human cacdavers [n-154]. Presence of additional heads of biceps brachii and any variation in the course of neurovascular bundle in the front of arm were noted. It was observed that the left upper limb of only one middle aged male cadaver had four heads of origin of biceps brachii i.e. the long head from supraglenoid tubercle of scapula, short head from tip of coracoid process of scapula and the two accessory heads from the anteromedial surface of the humerus between the insertion of coracobrachialis and the origin of brachialis. The musculocutaneous nerve took origin from the lateral cord normally and pierced through coracobrachialis to enter the flexor compartment of forearm. Then it passed between the two accessory heads before supplying brachialis and continued as lateral cutaneous nerve of forearm. Each head of biceps brachii was individually innervated by fibers from musculocutaneous nerve. No other anomalies in the neurovascular bundle were observed. Awareness of the different course of musculocutaneous nerve and origin of supernumerary heads of biceps brachii is of importance to academicians, surgeons, traumatologists, orthopaedicians and plastic