Hydroxyapatite Crystal Thickness and Buckling Phenomenon in Bone Nanostructure During Mechanical Tests.

An investigation of bone samples taken from the left ulna of New Zealand white rabbits, with and without stresses and hysteresis loop, was undertaken using Small Angle X-ray Scattering technique. The purpose of this study is to investigate the nanostructural changes in the mean size of hydroxyapatite crystals thickness (T) during different mechanical conditions. The experiments were performed using bone samples aged 2 and 4 weeks, with and without strontium ranelate treatment, after compressive load and hysteresis loop. We did not observe any clear effects of strontium ranelate on the bones since the MANOVA test for epiphysis and diaphysis were found. On the other hand, a significant difference appears in epiphysis between 2 and 4 weeks. Furthermore, a reduction in the mean size of hydroxyapatite crystal thickness was observed when the loading pressure force increased, due to the buckling phenomenon. A return of memory points in the elastic region of the bone was observed. The significance of these results lays on the development of nanoproducts, with properties that are closer to the actual bone structure.

Health-related quality of life (HRQoL) following transforaminal percutaneous endoscopic discectomy (TPED) for lumbar disc herniation: A prospective cohort study - early results.

BACKGROUND: Lumbar discectomy is among the most frequently performed procedures in spinal surgery. Transforaminal percutaneous endoscopic discectomy (TPED) is a minimally invasive technique that gains ground among surgeons in the recent years. TPED has been studied in terms of effectiveness, however little is known about its overall impact on health-related quality of life (HRQoL) of the patients. OBJECTIVE: To investigate the progress of HRQoL following TPED. PATIENTS AND METHODS: Seventy-six (76) patients were enrolled in the study. Mean age was 56.5 ±12.1 years with 38 (50%) males and 38 (50%) females. All patients underwent TPED at L3-L4 (27.6%), L4-L5 (52.6%) and L5-S1 (19.7%). SF-36 was used for the assessment of HRQoL preoperatively and at 6 weeks, at 3, 6 and 12 months after the procedure. RESULTS: All aspects of SF-36 questionnaire showed statistically significant improvement one year after the procedure (p< 0.001). Role limitations due to physical problems, bodily pain and role limitations due emotional problems showed the highest improvement, followed by physical functioning, vitality, social functioning, mental health and general health. CONCLUSIONS: TPED for lumbar disc herniation is associated with significant improvement in all aspects of health-related quality of life within 6 weeks postoperatively and the improvement remains significant one year after surgery, as measured by the SF-36 questionnaire.

Flexible memory-alloy instrumentation for unilateral transpedicular kyphoplasty and guided cement augmentation of the thoracic spine.

The purpose of this novel study was to investigate the feasibility of unilateral transpedicular balloon kyphoplasty particularly of the upper thoracic vertebrae using an 11- gauge balloon and cement inserter, and to study the morphological parameters of the thoracic spine pedicles. We used four fresh frozen cadaveric thoracic spines with intact rib cages and skin for kyphoplasty from T1 to T12 vertebrae under C-arm fluoroscopy. The most limiting width of the pedicles 2.46+/-0.32mm was in the middle levels (T5-T8). The absolute minimum height of the pedicles was at T1 (3.80-3.87mm). All regions of the vertebral body were effectively targeted for cement augmentation. The average cement load of all the vertebral bodies was 43,22%. Using the kyphoplasty technique in combination with the pre-bent 11mm memory-alloy cement inserter allowed targeting of the desired position of the vertebral body for effective vertebral body cement augmentation.

Silicone ring tourniquet versus pneumatic cuff tourniquet in carpal tunnel release: a randomized comparative study.

BACKGROUND: The aim of the present study was to compare the pain levels resulting from the use of a silicone ring tourniquet (SRT) to those resulting from the use of a classic pneumatic cuff tourniquet (PT) in patients undergoing carpal tunnel release under local anesthesia. MATERIALS AND METHODS: Fifty patients that underwent carpal tunnel release under local anesthesia were randomized using the technique of stratified randomization by minimization. A forearm tourniquet was applied: a standard PT was used in 25 patients, and an SRT was used in the other 25 patients (the model of SRT used was selected according to the standard systolic blood pressure). Patient demographics and complications were recorded. Pain levels were assessed with the visual analogue scale and were recorded (a) just after tourniquet application, (b) 5 min after tourniquet application, and (c) just before tourniquet removal. RESULTS: There was no statistical significant difference in patient demographics between the two groups. The mean tourniquet time was similar for both groups (p = 1.000). The difference between the mean final pain level and the mean initial pain level was statistically significant for the SRT group (p = 0.010) and highly statistically significant for the PT group (p < 0.001). The mean final pain level for the PT group was higher than that for the SRT group (p = 0.043). CONCLUSIONS: According to the findings of this study, in patients who underwent carpal tunnel release under local anesthesia, the pain levels at the end of the operation and those just before the removal of the tourniquet were higher in the PT group than in the SRT group of patients.

Mechanical characterization of bone graft substitute ceramic cements.

The aim of this laboratory work was to study the compressive and flexural characteristics of various commercially available bone graft substitute (BGS) ceramic cements, in their initial as-mixed condition, and compare them to polymethylmethacrylate (PMMA). The tested biomaterials were two different calcium phosphate cements, two different calcium sulphate cements, one nanocrystalline hydroxyapatite and one PMMA cement. All biomaterials were prepared according to manufacturers instructions and the methodology described in ISO 5833 (2002) for acrylic bone cement was followed, as the one closest approaching in vivo requirements. All BGS cements had a brittle behaviour and when subjected to mechanical stress they all failed under sudden crack propagations in their bulk. Both in compression and bending, all BGS cements failed under loads lower than those of PMMA. In compression, the calcium sulphate extra strength cement showed a strength value of approximately 60% of PMMA, the other cements following at a distance. In bending, all BGS cements showed strengths below 22% of PMMA. However, due to limited number and fragility of specimens, calculated bending strengths can only be considered as indicative figures with limited comparative value. The results of this in vitro study showed a varying mechanical performance between tested BGS ceramic cements, whilst all of them exhibited lower compression and bending strength than the selected PMMA. These findings, of course, cannot be directly extrapolated to surgical or clinical implications, since the adopted in vitro context does not necessarily reflect the actual in vivo conditions met by such biomaterials.

Evaluation of improvement in quality of life and physical activity after total knee arthroplasty in greek elderly women.

BACKGROUND: The aim of this study was to evaluate the changes in quality of life of patients after total knee arthroplasty and to assess the changes in physical activity by using a self-reported questionnaire and by counting the number of steps 3-6 months after post-operatively. METHODS: Included were fifty two elderly women (age 72.6±65.9 years, mean±SD) with knee osteoarthritis undergoing primary knee arthroplasty. Health-related quality of life, physical activity, pain and function and the number of steps were assessed before, 3 and 6 months post-operatively. We used the Medical Outcomes Study Short Form (SF-36), the Physical Activity Scale for the Elderly (PASE) and the pedometer SW200 Digiwalker of Yamax. RESULTS: Patients showed a significant improvement (p< 0.01, η2 =0.22) in health-related quality of life, particularly in physical function, (p<0 .001) body pain (p< 0.001) and vitality scale (p< 0.001) of SF-36 at 3 and 6 months after the procedure. Physical activity (PASE score) increased at 3 and 6 months after arthroplasty (p< 0.001, η2 =0.74), and the number of steps increased 6 months after, compared to the assessment that took place 3 months after operation (p< 0.001). CONCLUSIONS: Our results suggest that total knee arthroplasty leads to a gradual improvement in quality of life of elderly patients over the first 6 post-operative months.

Homocysteine and its relationship to deep venous thrombosis in patients undergoing total knee or hip arthroplasty.

UNLABELLED: Backround: The role of hyperhomocysteinemia as an independent risk factor for venous thrombosis after lower limb arthroplasty remains questionable. The objective of this study is to determine the relationship between hyperhomocysteinemia and postoperative thromboembolic events in patients undergoing total hip or knee arthroplasty. METHOD: Between September 2004 and June 2006, we studied 172 patients (41 male and 131 female) with mean age 70.2 years (48-85). Total plasma homocysteine as well as other thrombophilic agents (proteinC, protein S, Antithrombin III, Lupus anticoagulants, APC-Resistance) were measured preoperatively. Duplex sonography was performed twice postoperatively, on the 7(th) day (+/-2) and on the 42th day (+/- 2). Spiral CT was performed when pulmonary embolism was suspected. RESULTS: Four patients developed deep venous thrombosis from which two developed pulmonary embolism. Only one of these four patients had high levels of total plasma homocysteine. CONCLUSIONS: Total plasma homocysteine does not seem to affect the development of deep venous thrombosis in patients undergoing total knee or hip arthroplasty and receive low molecular weight heparine.

Experimental study of tendon healing early phase: is IGF-1 expression influenced by platelet rich plasma gel?

BACKGROUND: It is well established that growth factors play a critical role in the healing process of connective tissues. To our knowledge, there are no studies in literature concerning the influence of PRP on growth factors expression. HYPOTHESIS: The aim of this study was to assess the effect of a single application of platelet rich plasma (PRP) gel in a patellar tendon defect on the spatial and temporal expression of Insulin-like Growth Factor 1 (IGF-1) during tendon healing. MATERIALS AND METHODS: Twenty-four animals were randomized to receive PRP (PRPFast, Bioteck) in a gel form (PRP group) and 24 to serve as untreated controls (Control group). A defect of 3 mm x 10 mm was surgically created on the tendon under general anaesthetic and in the PRP group, PRP gel was applied to fill the tendon defect whereas no treatment was applied in the control group. Six animals (12 limbs) from each treatment-group were sacrificed after one, two, three and four weeks following treatment. Histological and immunohistochemical staining were performed. RESULTS: Histology revealed a faster healing process in the tendons of PRP group in comparison with the controls. In the first 2 weeks of healing, IGF-1 was found intracellularly in various type cells, whereas in the last 2 weeks of healing, IGF-1 was detected mainly in tenocytes. Both cytoplasmic and nuclear expressions were present, whereas the larger amounts of immunoexpression were localized in both epitenon and endotenon. A superior expression of IGF-1 was seen in PRP group compared with controls (p<0.0001) in both the epitenon and endotenon at each time point except at 4th week of healing where a superior expression of IGF-1 was shown in the endotenon of control group, compared to the PRP group (p<0.0001). CONCLUSION: PRP may improve tendon defect healing by overexpression of IGF-1. LEVEL OF EVIDENCE: Laboratory control animal study.

Total Dislocation of the Talus without a Fracture. Open or Closed Treatment? Report of Two Cases and Review of the Literature.

Complete dislocation of the talus not accompanied by a fracture is a very rare injury. The injury is encountered as a closed one even more rarely. Reviewing the literature we found that proposed treatments for total talus dislocation varied from primary talectomy or arthodesis (to avoid complications) to closed reduction and an under knee cast. Most importantly, there was no agreement among authors about the method of reduction (open/closed). We report our experience with two cases of closed total talus dislocation not accompanied by a fracture, and review the literature to retrieve evidence on whether a closed or open treatment should be preferred for this type of injury.

Bilateral transient bone marrow edema or transient osteoporosis of the knee in pregnancy.

Transient osteoporosis or transient bone marrow edema is an uncommon self-limiting condition of unknown etiology. The most commonly affected joint is the hip, followed by the knee, ankle, and the foot. Simultaneous involvement of both hips has been reported exclusively in pregnant women. Bilateral knee involvement during pregnancy seems to be extremely rare. We present a case of bilateral transient bone marrow knee edema during pregnancy with complete resolution of symptoms and radiological findings after 10 months.

Polymorphisms of the vitamin D receptor gene and stress fractures.

Our aim was to evaluate the association between VDR polymorphisms and calcaneal Stiffness Index (SI) with stress fractures in a case control study including male military personnel. Thirty- two patients with stress fractures were matched with 32 uninjured healthy volunteers (controls), by gender, age, height, body weight, and level of physical activity. The two groups were genotyped for the FokI, BsmI, ApaI, and TaqI polymorphisms of the VDR gene with PCR-RFLP method. In addition, calcaneal SI was measured by heel quantitative ultrasound in both groups. Data were analyzed by chi-squared test and logistic regression analysis. The f allele was significantly more frequent in patients than in controls (p=0.013), while the B allele showed such a tendency without reaching statistical significance (p=0.052). Among the entire cohort, a 2.7-fold and a 2.0-fold increase in risk of stress fractures was associated with the f and B alleles (OR, 2.7, 95% CI, 1.2-5.9; p=0.014 and OR, 2.0, 95% CI, 1.0-4.1; p=0.053, respectively). No statistically significant association was found between the incidence of stress fractures and t or a alleles. Decreased T-scores were also associated with the presence of f and B alleles. Mean values of T-scores of SI were statistically significantly lower in patients than in controls (p=0.018). These results suggest that the FokI and BsmI polymorphisms of the VDR gene could be associated with increased risk of stress fractures among military personnel. Moreover, a low calcaneal SI could represent a measurable index of this increased risk.

Insulin sensitivity increase after calcium supplementation and change in intraplatelet calcium and sodium-hydrogen exchange in hypertensive patients with Type 2 diabetes.

AIMS/HYPOTHESIS: To investigate the effect of oral calcium (Ca(2+)) supplementation on insulin sensitivity measured by the euglycaemic hyperinsulinaemic clamp, intraplatelet cationic concentration of Ca(2+) ([Ca(2+)](i)) and the transmembrane sodium-hydrogen exchanger (NHE) activity in erythrocytes in subjects with Type 2 diabetes and hypertension. PATIENTS AND METHODS: In this parallel randomized controlled single-blinded trial, 31 patients were allocated to receive either 1500 mg of Ca(2+) orally, daily (n = 15) or no treatment (n = 16) for 8 weeks. At baseline and at the end of the 8-week period insulin sensitivity, [Ca(2+)](i) and the first isoform of NHE (NHE-1) activity were measured. RESULTS: At the end of the study, subjects who received Ca(2+) supplementation showed higher insulin sensitivity (Delta M-value 0.32 +/- 0.5 mmol/min P < 0.05) and lower [Ca(2+)](i) (125.0 +/- 24.7 to 80.4 +/- 10.6 nmol/l, P < 0.05, mean +/- sem) and NHE-1 activity (79.5 +/- 10.0 to 52.1 +/- 6.4 mmol Na/l red cell/h, P < 0.05). None of the above parameters were changed in the control group. Simple regression analysis demonstrated the change in [Ca(2+)](i) significantly determined insulin sensitivity change (beta = -0.36, P < 0.05). CONCLUSIONS/INTERPRETATION: Oral Ca(2+) supplementation improves insulin sensitivity in patients with Type 2 diabetes and hypertension. These changes are likely to be mediated by changes in intracellular ionic Ca(2+). NHE-1 activity was also reduced after Ca(2+) supplementation but its role in insulin sensitivity requires further investigation.

Anterior cruciate ligament reconstruction: outcome using a patellar tendon bone (PTB) autograft (one bone block technique).

OBJECTIVE: The aim of this study was to determine the outcome of anterior cruciate ligament (ACL) reconstruction using a patellar tendon bone autograft (one bone block technique). METHOD: We retrospectively evaluated a case series of patients who had received arthroscopic ACL reconstructions using patellar tendon bone autograft. Fifty-four (54) ACL reconstructions were evaluated at a mean of 38 months (range 25-62 months). Clinical assessment was made using a modified Lysholm score, documentation of International Kappanee Documentation Committee (lKappaDC), the anterior knee pain questionnaire of Shelbourne and Trumper, and by KappaTau-Rolimeter arthrometric analysis. Radiographic assessments were also performed. RESULTS: Arthrometric analysis showed that 51 knees (94%) were graded Alpha or Beta with a median laxity of 2 mm, postoperatively. The Lysholm score improved postoperatively from 70 to 89. The patellar position in terms of congruence angle did not show any significant change, and the final shortening of the patellar tendon using the Insall-Salvati ratio was 6.07%. Only three patients complained of moderate pain on kneeling, one patient was unable to participate in strenuous works and one patient complained of harvest-site tenderness. CONCLUSION: It is concluded that the use of patellar tendon autograft with a single tibial-tubercule bone block and a strip of patellar periosteum have the advantages of being available and comparable in terms of graft size and strength and shows satisfactory results with reduced anterior knee pain.

The use of autologous PRP gel as an aid in the management of acute trauma wounds.

Autologous platelet-rich plasma (PRP) gel is increasingly used in the treatment of a variety of soft and bony tissue defects, such as accelerating bone formation and in the management of chronic non-healing wounds. We performed this study to assess the benefits of using autologous PRP gel in the treatment of acute limb soft tissue wounds. 59 patients with acute wounds (open fractures, closed fractures with skin necrosis and friction burns) were randomised into two groups. Group A (32 patients) were treated with conventional dressings and Group B (27 patients) were managed with local application of PRP gel. Gustillo grade IIIb or IIIc open fractures were not included in this study, as these injuries required coverage with flap. The clinical endpoints were the healing rate and/or the time required to bring about adequate tissue regeneration in order to undergo reconstructive plastic surgery. The rate of wound healing rate was significantly faster in Group B at week 1, 2 and 3 (p=0.003, p<0.001 and p<0.001, respectively). The mean time to plastic reconstruction in Group B was 21.26 days, S.D.=1.35 vs 40.6 days in Group A, S.D.=5.27 (p<0.001). This study has shown that PRP gel treatment can be a valuable and effective aid in the management of acute trauma wounds.

Maggot infestation (myiasis) of external fixation pin sites in diabetic patients.

Diabetic patients, and especially elderly patients in a low-nutritional or immunocompromised state, are prone to a variety of opportunistic infections. 'Myiasis' is a term that refers to non-iatrogenic infestation of tissues by larvae, commonly known as maggots, of dipterous flies. Myiasis as a complication of fracture treatment by means of external fixation of long bones has not been reported. We present three diabetic patients, who suffered maggot infestation of their external fixation pin holes, and their outcome. Diabetes, immobilization, poor hygiene and low immune status are predisposing factors for developing myiasis, an extremely rare complication for external fixation of fractures.

Stress fractures in military men and bone quality related factors.

The aetiology of stress fractures is multifactorial, and many risk factors have been implicated. The aim of this study was to explore the relationship between stress fractures, factors and biochemical markers related to bone metabolism, and calcaneal stiffness index measured by quantitative ultrasound in a case control study including male military personnel beyond basic training. Thirty-two male patients with stress fractures were matched with 32 uninjured-healthy volunteers by age, height, body weight and level of physical performance. A questionnaire concerning the calcium intake, alcohol consumption and smoking was completed, the values of several biochemical markers were measured from blood samples, and calcaneal quantitative ultrasound was measured by heel ultrasound for all participants. Statistically significant higher levels of albumin (4.59 +/- 0.28 vs. 4.40 +/- 0.25, p = 0.006) and lower levels of serum osteocalcin (6.26 +/- 1.74 vs. 7.40 +/- 1.80, p = 0.012), mean values of T-scores (- 0.21 +/- 0.95 vs. 0.33 +/- 0.82, p = 0.018) and Z-scores (- 0.14 +/- 0.81 vs. 0.33 +/- 0.71, p = 0.016) were found among patients compared to controls. Based on the results, it seems that a decreased bone turnover and a low calcaneal stiffness index may be related to the incidence of stress fractures amongst male military personnel.

Post-operative pain after knee arthroscopy and related factors.

The aim of this study was to explore the intensity of post-arthroscopy knee pain during the first 24 hours, and to study the influence of pre-operative pain, tourniquet time and amount of surgical trauma on post-arthroscopy pain. In 78 male patients that underwent elective arthroscopic menisectomy or diagnostic arthroscopy of the knee, preoperative and post-operative pain were registered using the Visual Analogue Scale. Variance for repeated measures and for independent observations was analysed. Supplementary analgesia was required for 23% of the patients, more often in the recovery room and between 2 and 8 hours postoperatively. Of all factors analyzed, only time was statistically significant in determining the level of post-operative pain. Supplementary analgesia was required only in patients that underwent operative arthroscopy, and more often in patients with tourniquet time of more than 40 minutes. In conclusions, post-operative time is the most significant factor related to the post-arthroscopy knee pain.

Multifocal infection after hip fracture fixation: a case report.

We present the case of a seventy five year old female diabetic patient, who sustained an inter-trochanteric fracture of her left hip and was treated by dynamic hip screw fixation on the same day. The patient developed multifocal infection with three different and unusual types of bacteria isolated in blood and wound cultures. In spite of aggressive and repeated wound debridement, infection and blood sugar levels were impossible to control until metal removal, which led to fracture malunion. The patient denied further hip reconstruction surgery and ended up mobilizing with a walker and a limp.Multifocal infection is possible even after a routine Orthopaedic procedure on a patient with precipitating factors no more than diabetes mellitus. It is important to be aware of the possibility of simultaneous wound infection and septicemia by different agents.

Intramuscular haemangioma of the extensor pollicis brevis muscle with periosteal reaction of the radius: a case report and review of the literature.

We report the rare case of a histologically proven mixed-type intramuscular haemangioma, adjacent to the periosteum of the radius, that caused a periosteal reaction. We also carried out a review of the literature relevant to this case. A 28-year-old male professional drummer presented with an 8-month history of pain and swelling of the dorsal aspect of the right radius. Diagnosis was established on the basis of plain radiographs and magnetic resonance imaging, and was confirmed by histology. The lesion was treated solely by resection of the soft-tissue mass. The patient remained asymptomatic 4 years post-operatively, with no radiographic signs of recurrence. From a review of the literature, it is evident that the terminology for haemangiomas causing regional bone changes is unclear. A new classification of the intramuscular haemangiomas is proposed in order to distinguish between lesions that, according to current knowledge, exhibit radiological and clinical areas of overlap.