BACKGROUND: Osteopetrosis is a collective term used for a pathological condition with defective function of osteoclasts presented with range of sclerosing bone diseases along with skeletal, renal, haematological & neurological manifestation. It may be autosomal recessive (ARO), autosomal dominant (ADO) and X-linked. It presents with hydrocephalus, short stature and anaemia, involvement of ocular nerve or facial nerve. Hypocalcemia, tetany, seizures & secondary hypoparathyroidism is known to occur. CASE REPORT: Two patients of osteopetrosis were posted for orthopaedic surgery. Both patients were operated under combined spinal epidural anaesthesia. 2ml of 0.5%Bupivacaine+30mcg clonidine was given intrathecally & epidural supplementation was given with Bupivacaine 3 cc increments after two segment regression of sensory level. Postoperative analgesia was provided by epidural Bupivacaine 0.125% along with Inj. Tramadol 50 mg on patient's request. CONCLUSION: Even if administration of anesthesia is a challenge in patients of Osteopetrosis, regional anaesthesia can be given safely with proper preoperative preparation & intraoperative care. KEY WORDS: osteopetrosis, femur fracture, combined spinal & epidural anaesthesia INTRODUCTION: Osteopetrosis is a collective term used for a pathological condition with defective function of osteoclasts presented with range of sclerosing bone diseases along with skeletal, renal, haematological & neurological manifestation. It is classified as Infantile malignant or (ARO), Intermediate type or (ARO) , Adult onset or (ADO)&X-linked Osteopetrosis. ARO is a life threatening condition manifests in first few months with life span of 6 to 10 yrs present with seizures with normal Calcium levels, renal tubular acidosis, cerebral calcification, developmental delay, hypotonia, retinal atrophy & sensorineural deafness. ADO is type I and type II. Type I is associated with reduced number & size of osteoclasts & involvement of ocular nerve while type II is associated with proliferation of large & multinucleated osteoclasts, involvement of facial nerve , bony sclerosis, renal tubular acidosis & cerebral calcification. In X-linked Osteopetrosis severe immunodeficiency is observed with ectodermal changes. The difficulties faced by Anaesthetists are difficult intubation due to facial deformities, head & mandibular involvement cervicomedullery stenosis may lead to cord trauma during intubation difficult spinal & epidural anaesthesia due to scoliosis and short stature. Leucoerythroblastic anaemia, pancytopenia, thrombocytopenia leading to excessive bleeding