Patients and methods Subjects We performed a vastus lateralis muscle biopsy in 15 women with OP undergoing surgery for fragility hip fracture and in 15 age-matched women (age range, 60–85 years) undergoing arthroplasty for hip osteoarthritis. The patients were informed about the experimental procedures and signed an informed consent form before participating in the study. The study was approved by the Ethical Committee of Tor Vergata University Hospital (protocol number 120/06). Bone mineral density evaluation DXA was performed with a Lunar iDXA apparatus (GE Healthcare, Madison, WI, USA). Lumbar spine (L1–L4) and femoral (neck and total) scans were performed, and BMD was analyzed

as previously described [13]. Dual-energy X-ray absorptiometry measures BMD (in grams per square centimeter) with a coefficient of variation of 0.7 %. In the OA group, all measurements were performed on the non-dominant side, DAPT in vivo while participants lay supine on an examination table with their limbs abducted away from PRIMA-1MET price the trunk. For the OP group, BMD was measured on the limb opposite the fracture side. Results are expressed as absolute values and as T-scores. Women with fragility hip fracture, a T-score ≤−2.5 SD, and a negative radiographic framework for hip OA were included in the OP group (BMD femoral neck range values, 0.454–0.645 g/cm2). Women with a positive radiogram for hip OA and T-score ≥−2.5 SD were

included in the OA group (BMD femoral neck range values, 0.845–1.197 g/cm2). Patients with neuromuscular diseases, Thalidomide diabetes mellitus, HBV, HCV, HIV infections, smoke or alcohol dependence, or treated with corticosteroids or hormonal drugs for a period exceeding 1 month were excluded from the study. The Harris Hip Score (HHS) of the affected side was calculated in all OA patients. HHS is a scale used to evaluate the degree of pain and functional impairment of the hip joint; it is based on a total of 100 (possible) points, and higher scores indicate better hip function [14]. No significant differences were found in BMI values between the two

groups (BMI mean values: OP, 24.4 kg/m2; OA, 23.8 kg/m2). Morphometric analysis Muscle biopsies were taken from the upper portion of the vastus lateralis during open surgery for hip arthroplasty or for synthesis with intramedullary nail. This muscle was chosen because it is hardly influenced by the fracture event, and it is a good indicator of systemic muscle atrophy related to the disease. Muscle specimens were frozen in melting isopentane and stored at −80 ° until use. Histological evaluations were performed on transverse cryostat sections (7 μm thick) stained with hematoxylin–eosin, Gomori trichrome, ATPase after preincubation at pH 4.2, NADH-dehydrogenase, and cytochrome c NVP-BGJ398 price oxidase. The presence of other myopathies was ruled out by routine histopathological survey.