Influence of defective bone marrow osteogenesis on fracture repair in an experimental model of senile osteoporosis

http://www.ncbi.nlm.nih.gov/pubmed/20014309

Trochanteric flip osteotomy for cranial extension and muscle protection in acetabular fracture fixation using a Kocher-Langenbeck approach

OBJECTIVE: To describe the advantages and surgical technique of a trochanteric flip osteotomy in combination with a Kocher-Langenbeck approach for the treatment of selected acetabular fractures. DESIGN: Consecutive series, teaching hospital. METHODS: Through mobilization of the vastus lateralis muscle, a slice of the greater trochanter with the attached gluteus medius muscle can be flipped anteriorly. The gluteus minimus muscle can then be easily mobilized, giving free access to the posterosuperior and superior acetabular wall area. Damage to the abductor muscles by vigorous retraction can be avoided, potentially resulting in less ectopic ossification. Ten consecutive cases of acetabular fractures treated with this approach are reported. In eight cases, an anatomic reduction was achieved; in the remaining two cases with severe comminution, the reduction was within one to three millimeters. The trochanteric fragment was fixed with two 3.5-millimeter cortical screws. RESULTS: All osteotomies healed in anatomic position within six to eight weeks postoperatively. Abductor strength was symmetric in eight patients and mildly reduced in two patients. Heterotopic ossification was limited to Brooker classes 1 and 2 without functional impairment at an average follow-up of twenty months. No femoral head necrosis was observed. CONCLUSION: This technique allows better visualization, more accurate reduction, and easier fixation of cranial acetabular fragments. Cranial migration of the greater trochanter after fixation with two screws is unlikely to occur because of the distal pull of the vastus lateralis muscle, balancing the cranial pull of the gluteus medius muscle.

[TGF-beta1 as a pathophysiological factor in fracture healing]

AIM: TGF-beta1 is an important local and systemic regulatory molecule during fracture healing. Various authors have shown differences in the systemic levels of TGF-beta1 over the time taken for bone healing in distraction osteogenesis and osteotomies. Previous studies have shown characteristic differences in the physiological levels of growth factors between normal fracture healing and delayed fracture union. The aim of the present study was to evaluate possible differences in sera levels of patients with normal and delayed union fracture healing. METHODS: Patients with long bone shaft fractures were recruited prospectively. Peripheral blood samples were collected over a period of 1 year using a standardized time schedule. At the end of the individual's investigation period, TGF-beta1 levels were determined. To achieve a homogeneous collective of patients, only those with a maximum of two fractures were included in the study. After matching for four criteria, we compared patients with normal fracture healing to patients with delayed unions. The fact of delayed union was accepted in case of failed consolidation 4 months after trauma. RESULTS: During a prospective study period of 1 year, 15 patients with normal fracture healing could be compared to 15 patients suffering from delayed union. By determining the absolute sera levels we found a typical increase of TGF-beta1 up to 2 weeks after fracture in both groups, with a subsequent decrease up to the sixth week after fracture. However, a decline in serum concentration occurred earlier in patients with delayed union, causing significantly lower TGF-beta1 levels in the non-union group 4 weeks after trauma (P=0.00006). CONCLUSION: Even with a relatively small number of patients, we could show a significant difference in serum concentrations of TGF-beta1 between the investigated groups. If these results can be verified within a larger collective, TGF-beta1 could be used as a predictive cytokine for delayed fracture healing.

Further reductions in nonvertebral fracture rate with long-term denosumab treatment in the FREEDOM open-label extension and influence of hip bone mineral density after 3 years

Limited data exist on the efficacy of long-term therapies for osteoporosis. In osteoporotic postmenopausal women receiving denosumab for 7 years, nonvertebral fracture rates significantly decreased in years 4-7 versus years 1-3. This is the first demonstration of a further benefit on fracture outcomes with long-term therapy for osteoporosis. INTRODUCTION This study aimed to evaluate whether denosumab treatment continued beyond 3 years is associated with a further reduction in nonvertebral fracture rates. METHODS Participants who completed the 3-year placebo-controlled Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months (FREEDOM) study were invited to participate in an open-label extension. The present analysis includes 4,074 postmenopausal women with osteoporosis (n = 2,343 long-term; n = 1,731 cross-over) who enrolled in the extension, missed ≤1 dose during their first 3 years of denosumab treatment, and continued into the fourth year of treatment. Comparison of nonvertebral fracture rates during years 1-3 of denosumab with that of the fourth year and with the rate during years 4-7 was evaluated. RESULTS For the combined group, the nonvertebral fracture rate per 100 participant-years was 2.15 for the first 3 years of denosumab treatment (referent) and 1.36 in the fourth year (rate ratio [RR] = 0.64; 95 % confidence interval (CI) = 0.48 to 0.85, p = 0.003). Comparable findings were observed in the groups separately and when nonvertebral fracture rates during years 1-3 were compared to years 4-7 in the long-term group (RR = 0.79; 95 % CI = 0.62 to 1.00, p = 0.046). Fracture rate reductions in year 4 were most prominent in subjects with persisting low hip bone mineral density (BMD). CONCLUSIONS Denosumab treatment beyond 3 years was associated with a further reduction in nonvertebral fracture rate that persisted through 7 years of continuous denosumab administration. The degree to which denosumab further reduces nonvertebral fracture risk appears influenced by the hip bone density achieved with initial therapy.