• 1
    Johnell O, Kanis J 2005 Epidemiology of osteoporotic fractures. Osteoporos Int 16: S3S7.
  • 2
    Seeman E 2002 Pathogenesis of bone fragility in women and men. Lancet 359: 18411850.
  • 3
    Hui SL, Slemenda CW, Johnston CC Jr 1990 The contribution of bone loss to postmenopausal osteoporosis. Osteoporos Int 1: 3034.
  • 4
    Johnell O, Kanis JA, Oden A, Johansson H, De Laet C, Delmas P, Eisman JA, Fujiwara S, Kroger H, Mellström D, Meunier PJ, Melton LJ III , O'Neill T, Pols H, Reeve J, Silman A, Tenenhouse A 2005 Predictive value of BMD for hip and other fractures. J Bone Miner Res 20: 11851194.
  • 5
    Frost HM 1987 Bone “mass” and the “mechanostat”: A proposal. Anat Rec 219: 19.
  • 6
    Högström M, Nordström A, Alfredson H, Lorentzon R, Thorsen K, Nordström P 2007 Current physical activity is related to bone mineral density in males but not in females. Int J Sports Med 28: 431436.
  • 7
    Lorentzon M, Mellström D, Ohlsson C 2005 Association of amount of physical activity with cortical bone size and trabecular volumetric BMD in young adult men: The GOOD study. J Bone Miner Res 20: 19361943.
  • 8
    Schoenau E, Werhahn E, Schiedermaier U, Mokow E, Schiessl H, Scheidhauer K, Michalk D 1996 Influence of muscle strength on bone strength during childhood and adolescence. Horm Res 45 (Suppl 1): 6366.
  • 9
    Hasegawa Y, Schneider P, Reiners C 2001 Age, sex, and grip strength determine architectural bone parameters assessed by peripheral quantitative computed tomography (pQCT) at the human radius. J Biomech 34: 497503.
  • 10
    Kaji H, Kosaka R, Yamauchi M, Kuno K, Chihara K, Sugimoto T 2005 Effects of age, grip strength and smoking on forearm volumetric bone mineral density and bone geometry by peripheral quantitative computed tomography: Comparisons between female and male. Endocr J 52: 659666.
  • 11
    Ferretti JL, Capozza RF, Cointry GR, Garcia SL, Plotkin H, Alvarez Filgueira ML, Zanchetta JR 1998 Gender-related differences in the relationship between densitometric values of whole-body bone mineral content and lean body mass in humans between 2 and 87 years of age. Bone 22: 683690.
  • 12
    Rittweger J, Beller G, Ehrig J, Jung C, Koch U, Ramolla J, Schmidt F, Newitt D, Majumdar S, Schiessl H, Felsenberg D 2000 Bone-muscle strength indices for the human lower leg. Bone 27: 319326.
  • 13
    Schoenau E, Neu CM, Beck B, Manz F, Rauch F 2002 Bone mineral content per muscle cross-sectional area as an index of the functional muscle-bone unit. J Bone Miner Res 17: 10951101.
  • 14
    Sumnik Z, Land C, Coburger S, Neu CM, Manz F, Hrach K, Schoenau E 2006 The muscle-bone unit in adulthood: Influence of sex, height, age and gynecological history on the bone mineral content and muscle cross-sectional area. J Musculoskelet Neuronal Interact 6: 195200.
  • 15
    Bakker I, Twisk JWR, van Mechelen W, Roos JC, Kemper HCG 2003 Ten-year longitudinal relationship between physical activity and lumbar bone mass in (young) adults. J Bone Miner Res 18: 325332.
  • 16
    Nordström A, Olsson T, Nordström P 2006 Sustained benefits from previous physical activity on bone mineral density in males. J Clin Endocrinol Metab 91: 26002604.
  • 17
    Eser P, Frotzler A, Zehnder Y, Wick L, Knecht H, Denoth J, Schiessl H 2004 Relationship between the duration of paralysis and bone structure: A pQCT study of spinal cord injured individuals. Bone 34: 869880.
  • 18
    Goemaere S, Van Laere M, De Neve P, Kaufman JM 1994 Bone mineral status in paraplegic patients who do or do not perform standing. Osteoporos Int 4: 138143.
  • 19
    Orwoll ES, Klein RF 1995 Osteoporosis in men. Endocr Rev 16: 87116.
  • 20
    Vanderschueren D, Venken K, Ophoff J, Bouillon R, Boonen S 2006 Sex steroids and the periosteum—reconsidering the roles of androgens and estrogens in periosteal expansion. J Clin Endocrinol Metab 91: 378382.
  • 21
    Rochira V, Balestrieri A, Madeo B, Zirilli L, Granata ARM, Carani C 2006 Osteoporosis and male age-related hypogonadism: Role of sex steroids on bone (patho)physiology. Eur J Endocrinol 154: 175185.
  • 22
    Szulc P, Uusi-Rasi K, Claustrat B, Marchand F, Beck TJ, Delmas PD 2004 Role of sex steroids in the regulation of bone morphology in men. The MINOS study. Osteoporos Int 15: 909917.
  • 23
    Van Pottelbergh I, Goemaere S, Kaufman JM 2003 Bioavailable estradiol and an aromatase gene polymorphism are determinants of bone mineral density changes in men over 70 years of age. J Clin Endocrinol Metab 88: 30753081.
  • 24
    Gennari L, Merlotti D, Martini G, Gonnelli S, Franci B, Campagna S, Lucani B, Dal Canto N, Valenti R, Gennari C, Nuti R 2003 Longitudinal association between sex hormone levels, bone loss, and bone turnover in elderly men. J Clin Endocrinol Metab 88: 53275333.
  • 25
    Fink HA, Ewing SK, Ensrud KE, Barrett-Connor E, Taylor BC, Cauley JA, Orwoll ES for the Osteoporotic Fractures in Men Study Group 2006 Association of testosterone and estradiol deficiency with osteoporosis and rapid bone loss in older men. J Clin Endocrinol Metab 91: 39083915.
  • 26
    Khosla S, Melton LJ III , Robb RA, Camp JJ, Atkinson EJ, Oberg AL, Rouleau PA, Riggs BL 2005 Relationship of volumetric BMD and structural parameters at different skeletal sites to sex steroid levels in men. J Bone Miner Res 20: 730740.
  • 27
    Lorentzon M, Swanson C, Andersson N, Mellström D, Ohlsson C 2005 Free testosterone is a positive, whereas free estradiol is a negative, predictor of cortical bone size in young Swedish men: The GOOD study. J Bone Miner Res 20: 13341341.
  • 28
    Mellström D, Johnell O, Ljunggren O, Eriksson AL, Lorentzon M, Mallmin H, Holmberg A, Redlund-Johnell I, Orwoll ES, Ohlsson C 2006 Free testosterone is an independent predictor of BMD and prevalent fractures in elderly men: MrOS Sweden. J Bone Miner Res 21: 529535.
  • 29
    Napoli N, Faccio R, Shrestha V, Bucchieri S, Rini G, Armamento-Villareal R 2007 Estrogen metabolism modulates bone density in men. Calcif Tissue Int 80: 227232.
  • 30
    van den Beld AW, de Jong FH, Grobbee DE, Pols H, Lamberts SWJ 2000 Measures of bioavailable serum testosterone and estradiol and their relationships with muscle strength, bone density, and body composition in elderly men. J Clin Endocrinol Metab 85: 32763282.
  • 31
    Bjornerem A, Emaus N, Berntsen GKR, Joakimsen R, Fonnebo V, Wilsgaard T, Oian P, Seeman E, Straume B 2007 Circulating sex steroids, sex hormone-binding globulin, and longitudinal changes in forearm bone mineral density in postmenopausal women and men: The Tromsø study. Calcif Tissue Int 81: 6572.
  • 32
    Zarrabeitia MT, Hernandez JL, Valero C, Zarrabeitia A, Amado JA, Gonzalez-Macias J, Riancho JA 2007 Adiposity, estradiol, and genetic variants of steroid-metabolizing enzymes as determinants of bone mineral density. Eur J Endocrinol 156: 117122.
  • 33
    Khosla S, Melton LJ III , Atkinson EJ, O'Fallon WM 2001 Relationship of serum sex steroid levels to longitudinal changes in bone density in young versus elderly men. J Clin Endocrinol Metab 86: 35553561.
  • 34
    Barrett-Connor E, Mueller JE, von Muhlen DG, Laughlin GA, Schneider DL, Sartoris DJ 2000 Low levels of estradiol are associated with vertebral fractures in older men, but not women: The Rancho Bernardo study. J Clin Endocrinol Metab 85: 219223.
  • 35
    Schiessl H, Frost HM, Jee WSS 1998 Estrogen and bone-muscle strength and mass relationships. Bone 22: 16.
  • 36
    Frost HM 1999 On the estrogen-bone relationship and postmenopausal bone loss: A new model. J Bone Miner Res 14: 14731477.
  • 37
    Van Pottelbergh I, Goemaere S, Zmierczak H, De Bacquer D, Kaufman JM 2003 Deficient acquisition of bone during maturation underlies idiopathic osteoporosis in men: Evidence from a three-generation family study. J Bone Miner Res 18: 303311.
  • 38
    Van Pottelbergh I, Goemaere S, Zmierczak H, Kaufman JM 2004 Perturbed sex steroid status in men with idiopathic osteoporosis and their sons. J Clin Endocrinol Metab 89: 49494953.
  • 39
    Baecke JA, Burema J, Frijters JE 1982 A short questionnaire for the measurement of habitual physical activity in epidemiological studies. Am J Clin Nutr 36: 936942.
  • 40
    Crabbe P, Bogaert V, De Bacquer D, Goemaere S, Zmierczak H, Kaufman JM 2007 Part of the interindividual variation in serum testosterone levels in healthy men reflects differences in androgen sensitivity and feedback set point: Contribution of the androgen receptor polyglutamine tract polymorphism. J Clin Endocrinol Metab 92: 36043610.
  • 41
    Bogaert V, Taes Y, Konings P, Van Steen K, De Bacquer D, Goemaere S, Zmierczak H, Crabbe P, Kaufman JM 2008 Heritability of blood concentrations of sex-steroids in relation to body composition in young adult male siblings. Clin Endocrinol (Oxf) 69: 129135.
  • 42
    Schiessl H, Ferretti JL, Tysarczyk-Niemeyer G, Willnecker J 1996 Noninvasive bone strength index as analysed by peripheral quantitative computed tomography. In: SchoenauE (ed.) Paediatric Osteology: New Developments in Diagnostics and Therapy. Elsevier Science, Amsterdam, The Netherlands, 141145.
  • 43
    Vermeulen A, Verdonck L, Kaufman JM 1999 A critical evaluation of simple methods for the estimation of free testosterone in serum. J Clin Endocrinol Metab 84: 36663672.
  • 44
    Szulc P, Claustrat B, Munoz F, Marchand F, Delmas PD 2004 Assessment of the role of 17beta-oestradiol in bone metabolism in men: Does the assay technique matter? The MINOS study. Clin Endocrinol (Oxf) 61: 447457.
  • 45
    Goetgeluk S, Vansteelandt S 2007 Conditional generalized estimating equations for the analysis of clustered and longitudinal data. Biometrics 64: 772780.
  • 46
    Kramer M 2005 R2 statistics for mixed models. Proceedings of the Conference on Applied Statistics in Agriculture, April 2005, Kansas State University, Manhattan, KS, USA.
  • 47
    Schoenau E, Neu CM, Rauch F, Manz F 2002 Gender-specific pubertal changes in volumetric cortical bone mineral density at the proximal radius. Bone 31: 110113.
  • 48
    Lorentzon M, Mellström D, Ohlsson C 2005 Age of attainment of peak bone mass is site specific in Swedish men: The GOOD study. J Bone Miner Res 20: 12231227.
  • 49
    Lorentzon M, Eriksson AL, Nilsson S, Mellström D, Ohlsson C 2007 Association between physical activity and BMD in young men is modulated by catechol-o-methyltransferase (COMT) genotype: The GOOD study. J Bone Miner Res 22: 11651172.
  • 50
    Lee KC, Jessop H, Suswillo R, Zaman G, Lanyon LE 2004 The adaptive response of bone to mechanical loading in female transgenic mice is deficient in the absence of oestrogen receptor-alpha and -beta. J Endocrinol 182: 193201.
  • 51
    Neu CM, Rauch F, Manz F, Schoenau E 2001 Modeling of cross-sectional bone size, mass and geometry at the proximal radius: A study of normal bone development using peripheral quantitative computed tomography. Osteoporos Int 12: 538547.