Summary Statement

Mesenchymal stem cells from minced umbilical cord fragments may represent a valuable cell population for cartilage and bone tissue engineering

Summary Statement

Preoperative bone-marrow-derived cell mobilization by G-CSF is a safe orthopaedic procedure and allows circulation in the blood of high numbers of CD34+ve cells, promoting osseointegration of a bone substitute.

Aim: Evaluate the incidence of complications related to timing (time between admission ad operation) and oral antiplatelet/anticoagulant therapy in patients treated for a hip fracture.

Materials and Methods: We prospectively evaluated 5 groups of 30 patients each, selected out of 875 consecutive patients admitted at the First Aid Unit of our Hospital with a proximal femoral fracture: group A – patients on Warfarin therapy, treated more than 5 days after admission (in order to allow the wash-out of Warfarin, as advised by many Anaesthesiologist Associations); B – patients treated more than 5 days after admission, not on Warfarin therapy; C – patients treated less than 48 hours after admission, not on Warfarin therapy; D – patients on Aspirin/NSAIDS therapy, treated more than 5 days after admission; E – patients on Ticlopidine/Clopidogrel therapy, treated more than 5 days after admission. The groups were comparable regarding age, gender, pre-trauma walking ability, mental state, fracture type and treatment. Blood loss, number of RBC transfusions, complications during hospitalization and up to 6 months after discharge, duration of hospitalization, degree of functional recovery and 2 years mortality were recorded. Statistical analysis included Kruskall-Wallis, U-Mann-Whitney and Logistic Regression Tests (SPSS 13.0 software).

Results: Group A showed higher preoperative blood loss (p=0.002), and longer hospitalization (p< 0.001), compared to all other groups. Groups D and E showed no higher complication and mortality rate in comparison to group B and C, while group A showed higher complication and mortality rate. Standing alone, timing and Warfarin appear not to be significant risk factors, while taken together they represent a high risk factor for complications ad mortality (p=0.009).

Conclusion: Patients on Warfarin therapy, affected by hip fracture, are at high risk of complications and mortality, if the recommendation of postponing treatment until drug wash-out is accepted. Reversal of anticoagulation using vitamin K and straight-forward treatment should be considered. Antiplatelet therapy appears not to have the same adverse effect as anticoagulant therapy.

Introduction: This paper presents the short term results of 56 (28 males and 28 females) consecutive Unicompartimental Knee Arthroplasties (UKAs) and 54 (29 males and 25 females) High Tibial Opening Wedge Osteotomies (HTOs), performed in two centres (Toronto-Canada and Torino-Italy), between 2001 and 2004.

The aim of this prospective study was to compare UKAs to HTOs, in terms of clinical and functional Results: Materials and Methods:

In all UKAs we implanted an Accuris prosthesis (Smith& Nephew, Memphis TN), in all HTOs we performed a medial opening wedge osteotomy, according to the surgical technique and syntesized with a Puddu Plate (Arthrex, Naples FL).

We evaluated all patients preoperatively and at 6 months postoperatively, at 1 year, 2 years and at the last follow-up visit (mean 3,5 years for UKAs and 2,5 years for HTOs), using the Knee Society Score (KSS) and the WOMAC (Western Ontario and McMaster Universities) Score.

Results: The mean age at operation was 55 years for the HTO group and 65 years for the UKA group.

Postoperative program for the HTO group was: 4 weeks of CPM (continuous passive movement), partial weight-bearing al 4 weeks (30–50% of body weight) and then full weight-bearing at 8 weeks postoperatively.

In the UKA group, full weight bearing was allowed immediately after operation.

We observed only one significant complication postoperatively: an early infection in an HTO patient. We thought this complication was not related to the treatment chosen, but to external factors, so we decided to exclude this patient from our study.

In the HTOs group, the KSS knee score (KS) and function score (FS) improved from respectively 38 and 55 preopertively to 76 and 91 at the final follow-up evaluation, while in the UKA group KS increased from 43 to 93 and FS increased from 50 to 84.

The WOMAC Score improved from respectively 48 (HTO Group) and 45 (UKA Group) preoperatively to 15 (HTO Group) and 14 (UKA Group) at the final follow-up evaluation.

Discussion and conclusion: According to both scores (Womac and KSS), the two groups did not differ significantly at 1 year, 2 year and last followup evaluation, considering the different ages of the patients (55 years of the HTO Group versus 64 years of the UKA group).

Comparison of study groups shows good outcome at early and mid-term follow-up. All patients had scores rated good to excellent (both KSS and WOMAC).

However, we found a little difference in KSS between the two groups: UKAs have a higher Knee Score (better knee assessment), while HTOs have a significantly higher Functional Score (better performances, maybe due to a more “anatomic saving” procedure).

This data suggests that the UKAs have better knee assessment, meanwhile the HTOs have better function. Given that, both treatments lead to a good to excellent outcome at early followup.

The failure rate of peritrochanteric fracture implants ranges from 5 to 20 % The aim of the present preliminary study is to evaluate the relationship between Singh index (SI), and failure of internal fixation (cut-out), examining bone mechanical properties from ex-vivo human femoral heads.

The failure rate of peritrochanteric fracture implants ranges from 5 to 20 % The aim of the present preliminary study is to evaluate the relationship between Singh index (SI), and failure of internal fixation (cut-out), examining bone mechanical properties from ex-vivo human femoral heads.

From a methodological point of view we decided to use SI on the basis of previous literature,, our data seems not to be influenced by the use of this methodological approach. > Three load speeds were set: 3, 10, 500 mm/min resulting values of BW/s were compared with Davy and Bergmann ones (obtained with instrumented prosthesis), and test validity was confirmed. In conclusion our data demonstrated that: cut out phenomenon occurs for lower mechanical load in femoral heads of patients with lower SI.

Aims: evaluate the relationship between Singh index (SI), bone mineral density (BMD) examining bone mechanical properties from ex-vivo human femoral heads.

Methods: we collected the femoral heads of 22 patients that underwent arthroplastic for fracture of femoral head under low energy trauma. 5 patients were male while 17 were female. In each patient a pelvis X-ray was performed to estimate Singh Index. From 2 to 3 bone cylinders of cancellous bone were obtained from each femoral head. 52 bone cylinders (7x10mm) were obtained. In each specimen densitometric scans were performed by means of a Hologic QDR 4500 X-ray densitometer, using a small animal software. The coefficient of variation (CV) was calculated by repositioning a sample for 5 scans by different operators. The data obtained were expressed as bone mineral content (BMC) and bone mineral density (BMD). Compression tests with a JJ Instruments T5K machine were conducted on 52 spongy bone cylinders. Each specimen was loaded in movement control; maximum failure load and Young modulus were recorded.

Results The CV for the precision was 1.8% for BMC and 2.7% for BMD. There are no differences between males and females in age, BMC, BMD and Young modulus, while there is a significant difference in maximum load and SI. As regards SI values, there are significant differences among different categories of SI for age, sex, BMC, BMD, Young modulus and maximum failure load. Considering each sample position, namely 1, 2 or 3, there was no significant difference in densitometric parameters and in mechanical properties Statistical analyses of correlations by Pearson’s coefficient showed significant inverse correlations between age and mechanical bone properties (Young modulus and maximum failure load), while the correlations between BMC, BMD and biomechanical bone behaviour were strictly direct Linear regression model demonstrated only maximum load predictors are Young modulus and BMD

Conclusions The maximum failure load is lower in females than in males with similar BMD but lower SI for different SI categories there are significant differences both in biomechanical behaviour both in densitometric parameters.The age is inversely correlated with bone densitometric features and bone biomechanical behaviour, while bone density is directly correlated with bone strength and elastic modulus.The bone strength is predicted with 93% accuracy by Young modulus and BMD.