Brillouin micro-spectroscopy of subchondral, trabecular bone and articular cartilage of the human femoral head.

Brillouin micro-spectroscopy is applied for investigating the mechanical properties of bone and cartilage tissues of a human femoral head. Distinctive mechanical properties of the cartilage surface, subchondral and trabecular bone are reported, with marked heterogeneities at both micrometric and millimetric length scales. A ubiquitous soft component is reported for the first time, characterized by a longitudinal modulus of about 4.3 GPa, possibly related to the amorphous phase of the bone. This phase is mixed, at micrometric scales, with a harder component, ascribed to mineralized collagen fibrils, characterized by a longitudinal modulus ranging between 16 and 25 GPa.

Differences in telomere length between sporadic and familial cutaneous melanoma.

BACKGROUND: Several pieces of evidence indicate that a complex relationship exists between constitutional telomere length (TL) and the risk of cutaneous melanoma. Although the general perception is that longer telomeres increase melanoma risk, some studies do not support this association. We hypothesize that discordant data are due to the characteristics of the studied populations. OBJECTIVES: To evaluate the association of TL with familial and sporadic melanoma. MATERIALS AND METHODS: TL was measured by multiplex quantitative polymerase chain reaction in leukocytes from 310 patients with melanoma according to familial/sporadic and single/multiple cancers and 216 age-matched controls. RESULTS: Patients with sporadic melanoma were found to have shorter telomeres compared with those with familial melanoma. In addition, shorter telomeres, while tending to reduce the risk of familial melanoma regardless of single or multiple tumours, nearly trebled the risk of single sporadic melanoma. CONCLUSIONS: This is the first time that TL has been correlated to opposite effects on melanoma risk according to the presence or absence of familial predisposition. Individual susceptibility to melanoma should be taken into account when assessing the role of TL as a risk factor.

BIOPHYSICAL STIMULATION FOR NONUNIONS.

Nonunions account for 5-10% on the total number of fractures. Biophysical stimulation is a non-surgical, conservative, frequently used therapy in nonunions and a greater efficacy has been demonstrated for pulsed electromagnetic fields (PEMF). The mechanisms of action of PEMF at cellular and molecular levels are still under debate and no dose-response study is available. Moreover, the vast majority of in vitro studies were conducted on healthy cells. The primary aim of the research was to investigate the capacity of PEMF with different exposure times to stimulate the osteogenic process in cells from the callus of a nonunion patient. Another important objective was the characterization of nonunion cells in terms of clonogenicity, cluster of differentiation expression and the tri-lineage differentiation capacity. Overall, the results indicated the presence of osteochondroprogenitor cells in the callus of a nonunion, with an impairment in the osteogenic differentiation process. PEMF may enhance cell viability, the formation of osteoid matrix and accelerate the process of osteogenic differentiation. BMP-4 production, TIMP1 and TIMP2 expression were influenced, as well as VEGFA, whose early upregulation may account for a possible improvement in both the osteogenic and vasculogenic processes. In conclusion, even with some discussed limitations, these preliminary data showed the presence of a multipotent progenitor population and suggested some hints of the effect of PEMF on nonunion cells.

Enhanced tibial osteotomy healing with use of bone grafts supplemented with platelet gel or platelet gel and bone marrow stromal cells.

BACKGROUND: There is great interest in the use of bone substitutes to improve bone repair. We compared the osteogenic potential of lyophilized bone chips combined with platelet gel, or with platelet gel and bone marrow stromal cells, with that of lyophilized bone chips alone in the healing of a high tibial osteotomy. METHODS: A prospective, randomized, controlled study was performed, and a standardized clinical model was applied. Thirty-three patients undergoing high tibial osteotomy to treat genu varum were enrolled and assigned to three groups. During the osteotomy, lyophilized bone chips with platelet gel were implanted into eleven patients (Group A), lyophilized bone chips with platelet gel and bone marrow stromal cells were implanted in twelve patients (Group B), and lyophilized bone chips without gel were placed in ten patients as controls (Group C). Six weeks after surgery, computed tomography-guided biopsies of the grafted areas were performed and the specimens were analyzed by histomorphometry. Clinical and radiographic evaluation was performed at six weeks, twelve weeks, six months, and one year after surgery. RESULTS: Histomorphometry at six weeks showed significantly increased osteoblasts and osteoid areas in both Group A (p = 0.006 and p = 0.03, respectively) and Group B (p = 0.009 and p = 0.001) in comparison with controls, as well as increased bone apposition on the chips (p = 0.007 and p = 0.001, respectively), which was greater in Group B than in Group A (p < 0.05). Group B showed significantly higher revascularization than the controls (p = 0.004). Radiographs revealed a significantly higher rate of osseointegration in Groups A and B than in the controls at six weeks (p < 0.005 and p < 0.0001, respectively). At the final evaluation at one year, the osseointegration was still better in Groups A and B than in Group C; however, all patients had complete clinical and functional evidence of healing. CONCLUSIONS: Adding a platelet gel or a platelet gel combined with bone marrow stromal cells to lyophilized bone chips increases the osteogenetic potential of the lyophilized bone chips and may be a useful tool in the treatment of patients with massive bone loss.

In vivo study on the healing of bone defects treated with bone marrow stromal cells, platelet-rich plasma, and freeze-dried bone allografts, alone and in combination.

The repair of confined trabecular bone defects in rabbits treated by autologous bone marrow stromal cells (BMSC), platelet-rich plasma (PRP), freeze-dried bone allografts (FDBA) alone and in combination (BMSC + PRP; FDBA + BMSC; FDBA + PRP; FDBA + PRP + BMSC) was compared. A critical size defect was created in the distal part of the femurs of 48 adult rabbits. Histology and histomorphometry were used in the evaluation of healing at 2, 4, and 12 weeks after surgery. The healing rate (%) was calculated by measuring the residual bone defect area. Architecture of the newly formed bone was compared with that of bone at the same distal femur area of healthy rabbits. The defect healing rate was higher in PRP + BMSC, FDBA + PRP, FDBA + BMSC, and FDBA + PRP + BMSC treatments, while lower values were achieved with PRP treatment at all experimental times. The highest bone-healing rate at 2 weeks was achieved with FDBA + PRP + BMSC treatment, which resulted significantly different from PRP (p < 0.05) and BMSC (p < 0.05) treatments. At 4 weeks, the bone-healing rate increased except for PRP treatment. Finally, the bone-healing rate of FDBA + PRP, FDBA + BMSC, and FDBA + PRP + BMSC was significantly higher than that of PRP at 12 weeks (p < 0.05). At 12 weeks, significant differences still existed between PRP, BMSC, and FDBA groups and normal bone (p < 0.05). These results showed that the combination of FDBA, BMSC and PRP permitted an acceleration in bone healing and bone remodeling processes.

Evaluation of bone healing enhancement by lyophilized bone grafts supplemented with platelet gel: a standardized methodology in patients with tibial osteotomy for genu varus.

Orthopedic practice may be adversely affected by an inadequate bone repair that might compromise the success of surgery. In recent years, new approaches have been sought to improve bone healing by accelerating the rate of new bone formation and the maturation of the matrix. There is currently great interest in procedures involving the use of platelet gel (PG) to improve tissue healing, with satisfactory results both in vitro and in maxillofacial surgery. Otherwise, to our knowledge, only a preliminary clinical study was undertaken in the orthopedic field [Kitoh et al., Bone 2004;35:892-898] and the efficacy of PG is still controversial. Our paper focuses on the effect on bone regeneration by adding PG to lyophilized bone chips used for orthopedic applications. The clinical model and the laboratory methodology were standardized. As a clinical model, we employed the first series of patients of a randomized case-control study undergoing high tibial osteotomy (HTO) for genu varus. Ten subjects were enrolled: in 5 patients lyophilized bone chips supplemented with PG were inserted during tibial osteotomy (group A); 5 patients were used as a control (group B) and lyophilized bone chips without gel were applied. Forty-five days after surgery, computed tomography scan guided biopsies of grafted areas were obtained and the bone maturation was evaluated by a standardized methodology: the osteogenic and angiogenic processes were semi-quantitatively characterized by using histomorphometry, and the mineral component of the lyophilized and host bone was analyzed by using X-ray diffraction technique with sample microfocusing and microradiography. Lyophilized bone with PG seems to accelerate the healing process, as shown by new vessel formation and deposition of newly formed bone, with no evidence of inflammatory cell infiltrate, when compared with lyophilized bone without gel. On the contrary, lyophilized bone undergo a resorption process, and a fibrous tissue often fills the spaces between chips. A histiocytic/giant-cell reaction is sometimes present. Otherwise, no differences have been found concerning microstructure. Our findings show the reliability of the methodology used to monitor early bone repair. The completion of the study and the evaluation of the ultimate clinical outcome are necessary in order to verify PG in vivo effects in orthopedic surgery.

Interlocking nail for femoral shaft fractures: is dynamization always necessary?

A series of 179 closed femoral fractures treated by static interlocking nailing (Grosse-Kempf nail) was reviewed to evaluate the effect of dynamization on the time to bony union. In 75 patients, dynamization was performed whereas in 104 the implant was left static. Union occurred in 178 patients. We observed one infection. Time to union was significantly shorter in the static group (103 days) compared to the dynamized group (126 days).

DNA detection by integrable electronics.

This paper presents a new electronic methodology to detect DNA hybridization for rapid identification of diseases, as well as food and environmental monitoring on a genetic base. The proposed solution exploits a new (electrical) capacitive measurement circuit, not requiring any prior labeling of the DNA (as it is often the case with the commonly employed optical detection). The sensitivity, the reliability, and the reproducibility of this device have been evaluated by experiments performed with a (non-integrated) prototype implementation, easily integrable in IC and/or micro-fabricated lab-on-a-chip.

MRI in diagnosis of osteoid osteoma of the proximal femur: a potentially deviating aspect. Description of a clinical case.

Osteoid osteoma constitutes 10-12% of all benign neoplasms of the bone. The tumor more frequently involves the male sex (male to female ratio 2.1:1) and it may be observed in all age groups, with evident predilection for the second decade of life. All of the skeletal segments may be affected, but the most frequent site is the long bones, in the diaphyseal, metaphyseal and more rarely epiphyseal regions. The lesion is characterized by an osteolytic area, the nidus, which is at times partially calcified, surrounded by an osteosclerotic zone that is more or less accentuated. Clinical suspicion and traditional radiography are essential in diagnostic orientation; usually, further imaging methods are also recommended, such as bone scan with Tc99, CT scan and MRI. This last method allows for easy localization of the lesion, although with a sensitivity that is less than that of the CT scan. Nonetheless, the finding, if not supported by clinical suspicion, may be dangerously deviating and it may orient diagnosis towards a more aggressive disease.

Traumatic injuries of the pelvis. SIOT paper 1967.

The paper that Prof. Campanacci read at the Annual Meeting of the Italian Society of Orthopaedics and Traumatology in 1967 was the product of vast research aimed at clarifying and classifying traumatic injuries of the pelvic girdle. The basic idea behind the study was that correct therapeutic conduct cannot neglect an in-depth knowledge of the pathologic anatomy and pathogenesis of the injury. What emerges, in addition to the knowledge of anatomopathology, is the continuing validity of the scientific method with which the problem was dealt with.

Ceramic-ceramic coupling. Total hip arthroplasty in young patients.

Between 1994 and 2000 at the 7th Division of the Rizzoli Orthopaedic Institute a total of 123 total hip arthroplasties were implanted in 105 patients aged under 40 years (mean age 32 years). In most of the cases the patient was affected with osteoarthrosis secondary to congenital hip dysplasia (35%) or osteonecrosis (29%). In all of the cases the same type of cup was press-fitted with alumina on alumina bearing surfaces. The stem was cemented in 4 cases. Six of the patients were submitted to prosthetic revision surgery: 1 as a result of deep infection, 2 recurring dislocation, 3 aseptic loosening of one of the components. Radiographic evaluation did not reveal signs of periprosthetic osteolysis. We did not observe any cases of rupture of the alumina head or any problems related to the modularity of the implant. The authors wish to stress the reliability of using alumina on alumina in a population with high functional demand.

Trochanteric arthroplasty in the treatment of sequelae after septic arthritis of the hip in infancy.

The authors describe 17 patients submitted to trochanteric arthroplasty between 1979 and 1999 at the Division of Pediatric Orthopaedics and Traumatology of the Rizzoli Orthopaedic Institute. There were 9 females and 8 males aged from 1 to 8 years (mean of 4) affected with the sequelae of septic arthritis of the hip with complete destruction of the epiphysis and of the femoral neck (types IVB and V according to the Hunka classification system). Mean follow-up was 9 years (minimum 1, maximum 23). Surgery is described and indications are discussed: this is the only type of treatment that may be offered in place of conservative treatment.

Primary osteogenic sarcoma of the clavicle. Case report.

The clavicle is an unusual site for any primary bone tumor, including osteogenic sarcoma. The authors report the case of a young girl aged 13 years who was affected with primary osteogenic sarcoma of the right clavicle, and who was treated by preoperative and postoperative chemotherapy and radical clavicle excision, including the acromioclavicular and the sternoclavicular joints.

Infected nonunion of the femur.

From 1988 to 2000, 21 patients with infected nonunion were treated by wide resection of the nonunion site and fixation with Ilizarov's external ring fixator. Of the 21 cases, 2 are still under treatment. 18 cases resolved. In two cases iterative fracture occurred, which was successfully treated by internal fixation. One case treated by external fixator failed; any further attempts at surgery were abandoned, and the patient was put in a brace. The ring fixator enabled a sufficiently wide resection to remove the infection. It also provided stability for long periods of time, unrestricted weight bearing, and, after resolution, the same set up was used to restore the femur to its original length by corticotomy and distraction according to Ilizarov.

Infected nonunion of the humerus.

Eight patients with infected nonunion of the humerus were treated surgically by removal of the instrumentation, surgical debridement or wide resection of the fracture site and stabilization in compression with an external fixator. A monoaxial external fixator was used in 5 patients, a circular external one in 3. The amount of time between trauma and treatment described was a mean of 13 months. Consolidation occurred in all of the patients after an average of 5.5 months. Long-term follow-up was obtained after a mean of 18 months (minimum 14, maximum 35). There was postoperative paralysis of the radial nerve in 2 of the cases, with complete recovery after 3 months. One case consolidated despite the persistence of a fistula.