Detailed Morphometry and Morphology of Bicipital Groove of Humerus among North Indian Population

Abstract

Introduction: Bicipital Groove (BG) represents an indentation on the proximal humerus which lodges tendon of Long Head of Biceps (LHB) brachii with synovial sheath. It’s medial and lateral walls are formed by lesser and greater tubercles respectively and the transverse humeral ligament converts it into a tunnel. Aim: To find a detailed morphometry attributing to morphological classification of BG among North Indian population. Materials and Methods: The present observational study was conducted over a period of one year on 100 adult intact dry humerii of unknown sexes obtained from Osteology Museum, Department of Anatomy, Shree Guru Gobind Singh Tricentenary (SGT) University, Gurugram, Haryana, India for several morphometric parameters like length, width, depth, length of medial and lateral walls as per descriptive statistics using Statistical Package for the Social Sciences (SPSS) version 21.0. The BG was classified according to the depth, opening angle and medial wall angles. Morphological features like Supratubercular Ridge (STR) of Meyer’s, bony spur on the floor of the groove or thickening of the walls were also observed and the frequency distribution was presented and Independent t-test was applied to compare the parameters on both sides. Results: Out of 100 sample, the mean of each parameter was length 72.98±7.54 mm, width 9.12±2.18.mm, depth 5.49±1.56 mm, medial wall and lateral wall length 54.83±8.62 mm and 60.82±8.01 mm respectively, opening angle 72.27±18.12º and medial angle 65.27±10.71º. Mostly BG had a depth of 4-6 mm with an incidence of 48%. Opening angle of BG was small (<95º) in 84% of humerus and maximum belonged to type 1 (90º to 75º) variety. Around 34% bones were showing morphological changes, out of which STR was 47.05%, bony spur on the floor of BG was 20.58% with wall thickening in 32.35% of total humerus. Conclusion: The detailed morphometry and classification of BG will serve as a reference base for North Indian population. It will be also useful for the clinicians as they should be well verged with the various morphological appearances of BG among dry bones and radiographs for proper diagnosis and treatment.