CONTEXT: We recently found that patients with X-linked hypophosphatemic rickets (XLH) have a muscle function deficit in the lower extremities. As muscle force and bone mass are usually closely related, we hypothesized that patients with XLH could also have a bone mass deficit in the lower extremities. OBJECTIVE: The study objective was to assess the muscle-bone relationship in the lower extremities of patients with XLH. SETTING: The study was carried out in the outpatients department of a pediatric orthopedic hospital. PATIENTS AND OTHER PARTICIPANTS: Thirty individuals with XLH (6 to 60 y; 9 male patients) and 30 age- and gender-matched controls participated. MAIN OUTCOME MEASURES: Calf muscle size and density as well as tibia bone mass and geometry were assessed by peripheral quantitative computed tomography. Muscle function was evaluated as peak force in the multiple 2-legged hopping test. RESULTS: Muscle force was significantly lower in XLH patients than in controls but muscle cross-sectional area did not differ (after adjustment for tibia length). External bone size, expressed as total bone cross-sectional area, was higher in the XLH group than in controls. The XLH cohort also had statistically significantly higher bone mineral content. CONCLUSIONS: Patients with XLH have increased bone mass and size at the distal tibia despite muscle function deficits.
CONTEXT: We recently found that patients with X-linked hypophosphatemic rickets (XLH) have a muscle function deficit in the lower extremities. As muscle force and bone mass are usually closely related, we hypothesized that patients with XLH could also have a bone mass deficit in the lower extremities. OBJECTIVE: The study objective was to assess the muscle-bone relationship in the lower extremities of patients with XLH. SETTING: The study was carried out in the outpatients department of a pediatric orthopedic hospital. PATIENTS AND OTHER PARTICIPANTS: Thirty individuals with XLH (6 to 60 y; 9 male patients) and 30 age- and gender-matched controls participated. MAIN OUTCOME MEASURES: Calf muscle size and density as well as tibia bone mass and geometry were assessed by peripheral quantitative computed tomography. Muscle function was evaluated as peak force in the multiple 2-legged hopping test. RESULTS: Muscle force was significantly lower in XLH patients than in controls but muscle cross-sectional area did not differ (after adjustment for tibia length). External bone size, expressed as total bone cross-sectional area, was higher in the XLH group than in controls. The XLH cohort also had statistically significantly higher bone mineral content. CONCLUSIONS:Patients with XLH have increased bone mass and size at the distal tibia despite muscle function deficits.
Authors: G P Colares Neto; R M R Pereira; J C Alvarenga; L Takayama; M F A Funari; R M Martin Journal: Osteoporos Int Date: 2017-02-13 Impact factor: 4.507
Authors: Dale Y Lee; Rachel J Wetzsteon; Babette S Zemel; Justine Shults; Jason M Organ; Bethany J Foster; Rita M Herskovitz; Debbie L Foerster; Mary B Leonard Journal: J Bone Miner Res Date: 2015-03 Impact factor: 6.741
Authors: Keith G Avin; Julian A Vallejo; Neal X Chen; Kun Wang; Chad D Touchberry; Marco Brotto; Sarah L Dallas; Sharon M Moe; Michael J Wacker Journal: Am J Physiol Endocrinol Metab Date: 2018-03-20 Impact factor: 4.310
Authors: Michael J Wacker; Chad D Touchberry; Neerupma Silswal; Leticia Brotto; Chris J Elmore; Lynda F Bonewald; Jon Andresen; Marco Brotto Journal: Front Physiol Date: 2016-05-13 Impact factor: 4.566
Authors: Mary D Ruppe; Xiaoping Zhang; Erik A Imel; Thomas J Weber; Mark A Klausner; Takahiro Ito; Maria Vergeire; Jeffrey S Humphrey; Francis H Glorieux; Anthony A Portale; Karl Insogna; Munro Peacock; Thomas O Carpenter Journal: Bone Rep Date: 2016-05-13