Outcome of surgical treatment of 54 Periprosthetic femoral fractures after total hip arthroplasty at mid term follow-up.

PURPOSE: The aim of the present study was to review the outcome of the surgical treatment of 54 periprosthetic femoral fractures (PFF) after total hip arthroplasty at a mean follow-up of 45 months. At final follow-up, the clinical outcome was measured using the Harris Hip score (HHS), the Karnofsky score (KS), while, the radiographic results were evaluated using the Beals and Tower's criteria. RESULTS: There were 13 post-operative complications that occurred in 10 patients with an overall re-operation rate of 11%. At final follow-up the mean HHS was 64 (range 20-100) and the mean KS was 66 (range 30-100). The radiological results were excellent in 89%, good in 9% and poor 2% of patients. The mortality rate was 0% at 3 months and 3.7% at one year post-operatively. The mean last HHS and KS of patients older than 75 years or with comorbidities were lower than that of patients younger than 75 years or without comorbidities. CONCLUSIONS: Although this study have shown that the surgical treatment of PFF was associated with a low re-operative rate, a good to excellent radiological results and a low mortality rate at 3 months and 1 year postoperatively, there was a marked functional deterioration in many patients. This decline of function could be attributed to the advanced age of patients and the presence of comorbidities.

Hip fracture: effectiveness of early surgery to prevent 30-day mortality.

To estimate the effect of delay to surgery for hip fracture on 30-day mortality using a risk adjustment strategy to control for the effect of demographic and clinical confounders. This observational study was carried out on all patients admitted with a hip fracture and discharged between January 2004 and December 2007 from a teaching hospital. Gender, age, time to surgery, mortality and medical comorbidities were derived from hospital discharge records (SDO), while International Normalised Ratio (INR) and American Society of Anaesthesiologists (ASA) score were retrieved from clinical records. Backward stepwise logistic regression was used to identify potential confounders in the relationship between time to surgery and mortality. A final multivariate logistic regression analysis was carried out controlling for the effect of confounders. In the 1320 patients who underwent surgery (mean age = 83 years, % female = 76.8%), time to surgery was two days or less in 746 (56.5%) patients and 30-day mortality was 3.5%. The interventions included partial or total hip replacement (N=820, 62.1%) and reduction and internal fixation (N=500, 37.9%). Multivariate logistic regression analysis showed that patients with a time to surgery greater than two days had a 2-fold increase in 30-day mortality after adjusting for age, gender, and comorbidity (OR=1.992, 95% CI 1.065-3.725). In a second model also including ASA score the odd ratio decreased to 1.839 (95% CI 0.971-3.486). Patients with a hip fracture should have surgery within two days from admission in order to reduce 30-day mortality.

Satellite cell characterization from aging human muscle.

OBJECTIVES: Satellite cells (SCs) are skeletal muscle progenitor cells located between the basal lamina and the sarcolemma of muscle fibers. They are responsible for muscle growth and repair. In humans, aging results in the depletion of the SC population and in its proliferative activity, but not in its function. It has not yet been determined whether under conditions of massive muscle fiber death in vivo, the regenerative potential of SCs is totally or partially compromised in old muscle. No studies have yet tested whether advanced age is a factor that restrains the response of SCs to muscle denervation in humans; this is also due to difficulties in the isolation and in the culture of SCs from a small human surgery fragment. The aim of this study was to study in depth muscle regeneration analysing the SC ability of SCs to proliferate and differentiate in aging human patients. METHODS: In order to study in more detail the molecular mechanism, the proliferative and differentiative ability of aging SCs, we isolated SCs from aging human muscle biopsies and analysed their morphology by transmission electron microscopy and immunocytochemical analysis (antibodies against desmin, N-CAM and M-cadherin) and their capacity to grow and to expand in vitro. Moreover, in order to evaluate gene expression of myogenic regulatory factors Myf5, MyoD and myogenin (Myf4), RT-PCR was performed. RESULTS AND DISCUSSION: SCs isolated from aging human muscle biopsies and plated into favorable proliferation and differentiation conditions were able to proceed through the myogenic program and actively form myotubes, although taking longer than the young control sample. The RT-PCR analysis together with the ultrastructural SC features showed that the myogenic potential seemed to be compromised during the aging human muscle proliferation in vitro.