17 Gaziantep Medical Journal Gaziantep Med J 2015;21(1):17-20 Research Article Received:10.08.2015 Accepted: 12.12.2015 ISSN 2148-3132 (print) ISSN 2148-2926 (online) www.gaziantepmedicaljournal.com DOI: 10.5455/GMJ-30-166016 Anatomical variations of the lumbar plexus in fetus Fetuslarda plexus lumbalis’in anatomik varyasyonları Sushma R Kotian 1 , Antony Sylvan D Souza 1 ,Biswabina Ray 2 , Suhani Sumalatha 1 1 Department of Anatomy, Kasturba Medical College, Manipal University, Manipal, India 2 Department of Anatomy, ESIC Medical College- PGIMSR, Bengaluru, India Abstract The lumbar plexus is formed within the psoas major muscle and is one of the main nervous pathways supplying the lower limb. Although we came across literature concerning the variations in lumbar plexus in adults, there is dearth of the same in foetuses. Aim of the study was to study the variations in lumbar plexus in foetus. The study was done bilaterally in 25 formalin-fixed fetuses (10 females, 15 males), age ranging from 20 to 37 weeks of gestation. The formation of lumbar plexus and their branching pattern were observed. The findings were noted and tabulated. Multiple variations were observed in the formation and branching pattern of lumbar plexus. Anatomical variations found in the present case may be injured during certain surgical procedures in infants and children, particularly in the lower abdominal region, e.g. appendectomy, inguinal hernia repair, iliac crest bone graft harvesting etc. As a consequence to such operations, several clinical conditions may be encountered such as meralgia paresthetica, groin pain and testicular pain in which the lateral femoral cutaneous, ilioinguinal and the genitofemoral nerves are mostly involved. Thus, awareness about the regional anatomy and its variations is essential for preventing intra-operative complications. Keywords: Lumbar plexus; fetus; variations Özet Pleksus lumbalis, psoas majör kasının içinde oluşan ve alt ekstremitenin inervasyonunu sağlayan ana sinir yollarından biridir. Pleksus lumbalis varyasyonları ile ilgili literatürlere baktığımızda erişkinlerde yapılanlar ile karşılaşmamıza rağmen, aynı konuda fetuslarda yapılanlarda çok eksiklik vardır. Çalışmanın amacı fetuslarda pleksus lumbalis varyasyonlarını incelemektir. Çalışma gestasyonel yaşı 20 ile 37 hafta arasında değişen, 25 adet formalin ile fiske edilmiş fetüste (10 kadın, 15 erkek) bilateral olarak yapıldı. Pleksus lumbalis’in oluşumu ve dallanma paterni incelendi. Bulgular kaydedildi ve tablo haline getirildi. Pleksus lumbalis’in oluşumu ve dallanma paterni ile ilgili çok sayıda varyasyonlar gözlemlendi. Bu çalışmada bulunan anatomik varyasyonlar özellikle alt karın bölgesinde, bebeklerde ve çocuklarda uygulanan bazı cerrahi işlemler sırasında yaralanabilir, örneğin apendektomi, kasık fıtığı onarımı, crista iliaca’dan kemik grefti alma gibi. Bu tür operasyonların bir sonucu olarak, çoğunlukla lateral kutanöz femoral, ilioinguinal ve genitofemoral sinirlerin etkilendiği meralgia paresthetica, kasık ağrısı ve testis ağrısı gibi çeşitli klinik durumlarla karşılaşılabilir. Bu nedenle, bölgesel anatomi ve varyasyonları hakkında bilinçli olmak intra-operatif komplikasyonların önlenmesi için gereklidir. Anahtar kelimeler: Pleksus lumbalis; fetus; varyasyonlar Introduction The lumbar plexus is formed within the substance of psoas major muscle by the union of ventral rami of the first three lumbar, most of the ventral ramus of the 4th lumbar and a slender branch arising from the 12th thoracic nerve. Although we came across literature concerning the variations in lumbar plexus in adults (1-3), there is dearth of the same in fetuses. Surgical procedures like inguinal hernia repair, colostomy, appendectomy frequently done in infants and children may accidently involve these varied branches of the lumbar plexus and cause obvious damage. As it is difficult to get cadavers of that age group, the present study was conducted on dead fetuses. Materials and Methods The present study was conducted in the department of Anatomy, Kasturba Medical College, Manipal. The study was done bilaterally in 25 formalin-fixed fetuses (15 males, 10 females) of age ranging from 20 to 37 weeks of gestation. The spontaneously aborted and stillborn fetuses were procured from the department of Obstetrics and Gynaecology, Kasturba Hospital Manipal. Fetuses with any external deformity were excluded from the study. The fetuses were meticulously dissected and the formation of lumbar plexus and their branching pattern were observed. The findings were noted and tabulated. Results Multiple variations were observed in the formation and branching pattern of lumbar plexus (Table 1). Absence of the ilioinguinal nerve (IIN) was common and was reported in four cases (Figure 1). A double IIN was also observed in one case. The nerve was initially single close to its origin but later Correspondence: Dr.Suhani Sumalatha, Senior Grade Lecturer Dept. of Anatomy, Kasturba Medical Collage Manipal University, Manipal-576104, India Tel+91-820-2922327 suhani.s@manipal.edu