Dataset Information

Muscle function, dynamic loading, and femoral neck structure in pediatric females.

ABSTRACT: Muscle forces influence the development of bone mass and structure, but dynamic loading via impact exercise is considered particularly osteogenic. We hypothesized that indices of local muscle function and physical activity exposure would predict femoral neck (FN) structure in premenarcheal females.We tested this hypothesis in 76 healthy, premenarcheal girls (46 gymnasts and 30 nongymnasts). Height, weight, Tanner breast stage, and prior year nonaquatic, organized physical activity level (PAL) were recorded semiannually. Hologic dual-energy x-ray absorptiometry scans (whole body, left FN) yielded total body nonbone lean mass and bone outcomes, including narrow neck (NN) hip structural analysis data. Dynamometers assessed nondominant hand grip and left hip flexion/extension indices. Parsimonious regression models tested the following as predictors of bone outcomes: local muscle function, PAL, gymnast status, and lean mass, accounting for Tanner breast stage and height, as appropriate.Hip flexion indices were significantly correlated with indices of FN mass, density, structure, and strength (P < 0.05). However, the entry of PAL, gymnast status, and lean mass into regression models supplanted local muscle function explanatory value. In contrast, for many variables, the significant association of gymnast status persisted after accounting for physical maturity, body size/lean mass, and PAL. For all skeletal indices except FNArea, NNwidth, NN endosteal diameter, and NN buckling ratio, gymnast status was more strongly associated with bone outcomes than PAL.Greater activity doses and exposure to extreme dynamic loading provide independent benefits to FN structure during growth. Furthermore, weight-bearing activity and high-impact exercise exposure appear superior to local muscle force measures for prediction of FN structure.

SUBMITTER: Dowthwaite JN

PROVIDER: S-EPMC3992432 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Muscle function, dynamic loading, and femoral neck structure in pediatric females.

Dowthwaite Jodi N JN Rosenbaum Paula F PF Sames Carol A CA Scerpella Tamara A TA

Medicine and science in sports and exercise 20140101 5

<h4>Purpose</h4>Muscle forces influence the development of bone mass and structure, but dynamic loading via impact exercise is considered particularly osteogenic. We hypothesized that indices of local muscle function and physical activity exposure would predict femoral neck (FN) structure in premenarcheal females.<h4>Methods</h4>We tested this hypothesis in 76 healthy, premenarcheal girls (46 gymnasts and 30 nongymnasts). Height, weight, Tanner breast stage, and prior year nonaquatic, organized ...[more]

PMID: 24743106

Similar Datasets

Project description:Teriparatide (TPTD) reduces risk of both vertebral and nonvertebral fracture, but increases bone mineral density (BMD) much more at the spine than the hip. TPTD and mechanical loading may have a synergistic anabolic effect on BMD, which may help explain these site-specific differences. Under normal daily activity, the femoral neck (FN) is under bending, placing one side under tension and the other under compression. We sought to further understand the relationship between mechanical loading and TPTD at the hip by investigating the effect of tensile versus compressive loading on TPTD stimulated bone formation indices in the human FN. Thirty-eight patients receiving total hip replacements for osteoarthritis were randomized to receive placebo (PBO) or TPTD for a mean treatment duration of 6 weeks prior to surgery, and double tetracycline labeling was administered to allow assessment of bone formation. The FN was harvested during surgery and analyzed for dynamic bone formation indices in the compressive and tensile regions of the endocortical and periosteal envelopes. Regression models relating outcome measures to patient characteristics including sex, age, body weight, and FN geometry were also analyzed. Overall, bone formation was higher with TPTD versus placebo on the endocortical surface, but not the periosteal surface. The level of bone formation in both TPTD and placebo groups was greater on the tensile endocortical surface and the compressive periosteal surface. There was a trend toward decreased endocortical eroded surface with TPTD in the compressive but not the tensile region. Patient age and sex explained the greatest variability in endocortical bone formation, and patient body mass and sex explained the greatest variability in periosteal bone formation. Our data represent the first dynamic comparison of teriparatide treatment under two loading modalities in human FN samples. Future work could determine whether specific hip loading intervention could amplify the benefits of teriparatide on the hip in clinical settings.

Project description:BackgroundComplex proximal femoral deformities, including an elevated greater trochanter, short femoral neck, and aspherical head-neck junction, often result in pain and impaired hip function resulting from intra-/extraarticular impingement. Relative femoral neck lengthening may address these deformities, but mid-term results of this approach have not been widely reported.Questions/purposesDo patients who have undergone relative femoral neck lengthening show (1) less hip pain and greater function; (2) improved radiographic parameters; (3) significant complications requiring subsequent surgery; and (4) progression of osteoarthrosis (OA) or conversion to total hip arthroplasty (THA) at mid-term followup?MethodsWe retrospectively reviewed 40 patients (41 hips) with isolated relative femoral neck lengthening between 1998 and 2006 with sequelae of Legg-Calvé-Perthes disease (38 hips [93%]), slipped capital femoral epiphysis (two hips [5%]), and postseptic arthritis (one hip [2%]). During this time, the general indications for this procedure included a high-riding greater trochanter with a short femoral neck with abductor weakness and symptomatic intra-/extraarticular impingement. Mean patient followup was 8 years (range, 5-13 years), and complete followup was available in 38 patients (39 hips [95%]). We evaluated pain and function with the impingement test, limp, abductor force, Merle d'Aubigné-Postel score, and range of motion. Radiographic parameters included trochanteric height, alpha angle, and progression of OA. Subsequent surgeries, complications, and conversion to THA were summarized.ResultsThe proportion of positive anterior impingement tests decreased from 93% (38 of 41 hips) preoperatively to 49% (17 of 35 hips) at latest followup (p = 0.002); the proportion of limp decreased from 76% (31 of 41 hips) to 9% (three of 35 hips; p < 0.001); the proportion of normal abductor strength increased from 17% (seven of 41 hips) to 91% (32 of 35 hips; p < 0.001); mean Merle d'Aubigné-Postel score increased from 14 ± 1.7 (range, 9-17) to 17 ± 1.5 (range, 13-18; p < 0.001); mean internal rotation increased to 25° ± 15° (range, 0°-60°; p = 0.045), external rotation to 32° ± 14° (range, 5°-70°; p = 0.013), and abduction to 37° ± 13° (range, 10°-50°; p = 0.004). Eighty percent of hips (33 of 41 hips) showed normal trochanteric height; alpha angle improved to 42° ± 10° (range, 27°-90°). Two hips (5%) had subsequent surgeries as a result of lack of containment; four of 41 hips (10%) had complications resulting in reoperation. Fourteen of 35 hips (40%) showed progression of OA; four of 40 hips (10%) converted to THA.ConclusionsRelative femoral neck lengthening in hips with combined intra- and extraarticular impingement results in reduced pain, improved function, and improved radiographic parameters of the proximal femur. Although lack of long-term complications is gratifying, progression of OA was not prevented and remains an area for future research.

Project description:ObjectiveTo investigate the effects of postoperative femoral neck shortening in patients with femoral neck fractures fixed with femoral neck system screws (FNS) and to explore the factors influencing femoral neck shortening.MethodTo retrospectively analyze the data of 113 patients with femoral neck fractures admitted to the Second Hospital of Fuzhou City, affiliated with Xiamen University, between December 2019 and January 2022. Of these, 87 patients were followed up for more than 12 months, 49 men and 38 women: 36 cases of Garden I and II fractures and 51 cases of Garden III and IV fractures, to record the patient's hip Harris score at 12 months postoperatively. Patients were divided into femoral neck shortening group and femoral neck no shortening group according to their regular postoperative follow-up radiographic measurements. To count the incidence of femoral neck shortening, a comparison of postoperative complication rates and hip Harris scores between the two groups was made. Statistical comparison of the two groups and a multifactorial logistic regression analysis were also performed to analyze the factors affecting femoral neck shortening.ResultsAll 87 patients were followed up for more than 12 months after surgery. In 34 of these cases, neck shortening occurred, and the incidence rate was 39.1%. 15 cases of severe shortening, incidence of 17.2%; fracture healing 84 cases, fracture healing rate of 96.5%. The hip Harris score was 83.99 (81.95, 89.20) in the neck shortening group at 12 months postoperatively, 90.87 (87.95, 94.80) for the group without neck shortening; the difference between the two groups was statistically significant (P < 0.01). 32 cases of fracture healing in the neck shortening group at 12 months after surgery, fracture healing rate of 94.1%; 52 cases healed without neck shortening group, fracture healing rate of 98.1%. The difference between the two groups was not statistically significant (P = 0.337). High incidence of neck shortening after FNS fixation of femoral neck fractures, cortical comminution of the severed end, fracture fractionation and quality of reduction were significantly correlated with neck shortening.ConclusionHigh incidence of postoperative neck shortening after internal fixation of femoral neck fractures with the femoral neck system, the cortical comminution, the type of fracture, and the quality of fracture reduction are the influencing factors; femoral neck shortening can affect postoperative hip function, but does not affect fracture healing.

Project description:ObjectiveThis meta-analysis aimed to compare the relative safety and efficacy of cannulated compression screw (CCS) and femoral neck system (FNS) in treating patients with femoral neck fractures and to provide evidence-based medical evidence for FNS in treating femoral neck fractures.MethodsPubMed, Embase, Cochrane, and China National Knowledge Infrastructure databases were searched to collect outcomes related to femoral neck fractures treated with FNS and CCS, including time to fracture healing, incidence of non-union, incidence of osteonecrosis of the femoral head, incidence of failure of internal fixation, rate of femoral neck shortening, Harris hip score, Barthel index, operative time, intraoperative blood loss, fluoroscopy frequency, and complications. A meta-analysis was performed using RevManv5.4 (The Cochrane Collaboration) and Stata v14.0 software.ResultsThis analysis included 21 studies involving 1,347 patients. The results showed that FNS was superior to CCS in terms of fracture healing time [mean difference (MD) = -0.75, 95% CI = (-1.04, -0.46), P < 0.05], incidence of bone non-union [odds ratio (OR) = 0.53, 95% CI = (0.29, 0.98), P = 0.04], incidence of osteonecrosis of the femoral head [OR = 0.49, 95% CI = (0.28, 0.86), P = 0.01], incidence of internal fixation failure [OR = 0.30, 95% CI = (0.18, 0.52), P < 0.05], rate of femoral neck shortening [OR = 0.38, 95% CI = (0.27, 0.54), P > 0.05], Harris hip score [MD = 3.31, 95% CI = (1.99, 4.63), P < 0.001], Barthel index [MD = 4.31, 95% CI = (3.02, 5.61), P < 0.05], intraoperative bleeding [MD = 14.72, 95% CI = (8.52, 20.92), P < 0.05], fluoroscopy frequency [OR = 0.53, 95% CI = (0.29, 0.98), P = 0.04], and complications [OR = 0.31, 95% CI = (0.22, 0.45), P < 0.05]. The difference between FNS and CCS in operative time was not statistically significant [MD = -2.41, 95% CI = (-6.88, 2.05), P = 0.29].ConclusionFNS treatment of femoral neck fracture can shorten the fracture healing time; reduce the incidence and translucent rate of bone non-union, osteonecrosis of the femoral head, and internal fixation failure; reduce intraoperative blood loss and postoperative complications; and improve hip joint function and activity. We are confident in the findings that FNS, an effective and safe procedure for internal fixation of femoral neck fractures, is superior to CCS.

Dataset Information

Muscle function, dynamic loading, and femoral neck structure in pediatric females.

Publications

Muscle function, dynamic loading, and femoral neck structure in pediatric females.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets