Effect of changes in serum levels of endogenous hydrogen sulfide on fracture healing: Study protocol clinical trial (SPIRIT compliant)

BACKGROUND

Fracture is a common disease; many factors affect fracture healing. Recent studies have confirmed that hydrogen sulfide (H2S) plays an essential role in bone formation, but most of these studies are drawing conclusions based on animal experiment; whether H2S could promote fracture healing in patients is still unclear. We aim to investigate the change of serum H2S in fracture patients, and analyze its effort on fracture healing.

METHODS

This is a single-center, prospective cohort study. Patients with spinal or limb fracture will be recruited. Patient's serum and urine will be collected at baseline for examination (serum H2S, β-CTX, OC, PINP, 25-OH-VitD3, S-CTX, urinary calcium, and urinary creatinine). All patients will be followed-up for 24 months in outpatients settings, the image of X-ray or CT will be reviewed and fracture healing will be judged by 2 experienced orthopedic physicians. The difference in serum parameters especially H2S will be compared between patients with fracture healed within 9 months and those with fracture unhealed at 9 months.

DISCUSSION

Results of the trial could provide insight into influence of H2S on fracture healing.

ETHICS AND DISSEMINATION

The study was approved by the ethics committee of School of Medicine UESTC & Sichuan Provincial People's Hospital Ethics Committee. All the participants will be asked to provide written informed consent before data collection. The findings of the study will be published in peer-reviewed journals and will be presented at national or international conferences.

Canine model of crush syndrome established by a digital crush injury device platform

OBJECTIVE

To establish a canine model of crush syndrome (CS).

METHODS

A total of 16 healthy adult female Beagle dogs were randomly divided into the control group (n=8) and the experimental group (n=8). The crush injury was created in the left hind leg of each dog in the experimental group.

RESULTS

The biochemical indexes in the experimental group changed significantly compared to the values before extrusion. And they were also significantly different from the values of the control group. The glomerular capillary dilation, renal tubular epithelial cell degeneration, and renal interstitial lymphocytic infiltration were found in the kidneys.

CONCLUSION

The canine CS model established by the digital crush injury device platform was successful according with the diagnosis of CS. It is good for the investigation of the CS mechanism and treatment using this model.

D-dimer as an applicable test for detection of posttraumatic deep vein thrombosis in lower limb fracture

Measuring the plasma levels of D-dimer is an accurate and easy modality to detect deep vein thrombosis (DVT) in nontraumatic settings. However, the diagnostic reliability of D-dimer assays in detecting posttraumatic DVT among patients with lower limb fracture undergoing orthopedic surgery is not validated. In this study, 141 patients with lower limb fracture admitted through the emergency department and undergoing orthopedic surgery were enrolled. Postoperative venous blood samples for D-dimer assay were taken on the 1st, 7th, and 28th postoperative days. Color Doppler sonography examination of both lower limbs was performed at the same time as a standard test. Eight out of the 141 patients (6%) had acute DVT based on Color Doppler sonography. Mean D-dimer was 2160 ng/mL in DVT positive patients and 864 in DVT negative patients. D-dimer levels greater than 1000 ng/mL were 100% sensitive and 71% specific for detecting postoperative DVT. D-dimer assay is a useful and sensitive test for detecting posttraumatic DVT.

Changes in Biochemical Markers after Lower Limb Fractures

Background: The bone remodeling sequence after bone fracture changes the concentrations of biochemical bone markers, but the relationships of fracture size and of healing time to changes in biomarkers are unclear. The present pilot study was undertaken to determine the changes found in serum bone markers after plate osteosynthesis of closed distal tibial and malleolar fractures during a study period of 24 weeks.

Methods: We measured tatrate-resistant acid phosphatase (TRACP 5b), collagen type I C-terminal telopeptide (ICTP), bone-specific alkaline phosphatase (bone ALP), osteocalcin (OC), procollagen type I C-terminal propeptide (PICP), procollagen type III N-terminal propeptide (PIIINP), and human cartilage glycoprotein 39 (YKL-40) in 20 patients with lower limb fractures (10 malleolar, 10 tibia). A physical examination and radiographs were completed to assess evidence of union.

Results: All malleolar fractures healed within 6 weeks, whereas 2 tibial fractures did not show complete bone healing after 24 weeks. Changes were comparable but more pronounced in the tibia group, and marker concentrations remained increased at the end of study (bone ALP, 86 vs 74 U/L; OC, 14.9 vs 7.7 μg/L; ICTP: 5.6 vs 3.3 μg/L at day 84 after osteosynthesis, P <0.05 in tibia; 80 vs 70 U/L, 8 vs 5.2 μg/L, and 3.5 vs 3.2 μg/L, respectively, in the malleolar fracture group).

Conclusions: In normal bone healing, changes in bone turnover markers were primarily dependent on the fracture size. Delayed tibia fracture healing may involve a disturbance in bone remodeling.

[Comparative characteristic of serpin--alpha-1 proteinase inhibitor in human and mice serum]

Serpin alpha-1-proteinase inhibitor have been studied in human subjects and in mice of different lines as acute phase reactant and during tumor development. In humans, there was no difference of serpin activity between men and women. Increased activity was noted in men with acute trauma (acute phase reaction). Comparatively to male, in female mice of different lines decreased activity of serum alpha-1-proteinase inhibitor, was shown. There was no increase of alpha-1-proteinase inhibitor activity during inflammation induced by zymosan administration in mice. alpha-1-proteinase inhibitor belongs to acute phase reactants in humans but not in mice; for mice alpha-2-macroglobulin is a more typical acute phase reactant as compared to alpha-1-proteinase inhibitor. Murine tumor development (hepatoma HA-1, lymphosarcoma LS, Lewis lung adenocarcinoma) was followed by a decreased activity of serum alpha-1-proteinase inhibitor both in successfully treated and untreated groups. According to data of literature, similar dated were obtained in humans with tumors. It was suggested that changes of expressiln of alpha-1-proteinase inhibitor by tumors and its secretion were involved in decreased activity of alpha-1-proteinase inhibitor.

C-reactive protein to transthyretin ratio for the early diagnosis and follow-up of postoperative infection

The clinical usefulness of C-reactive protein (CRP) and of transthyretin (TTR) for the early diagnosis and follow-up of infection after an open fracture was prospectively investigated (cohort A). It was complemented by a retrospective study of trauma patients admitted to an intensive care unit (cohort B). Serial determinations of serum CRP and TTR concentrations were first performed in uninfected patients from cohort A to define a reference profile during the early postoperative period. It showed a concomitant increase in CRP and decrease in TTR concentrations, followed by progressive return to initial values in patients free from bacterial infection. Variations of the CRP/TTR ratio were analyzed. Recovery phase was defined by an exponential evolution of the two plasma proteins and of their ratio value. The CRP and TTR concentrations were independent of sex and severity of the trauma. In the case of postoperative infection, patients of cohort A revealed amplified CRP and TTR responses usually preceding the occurrence of clinical signs. During successful antibiotic therapy, their recovery response became superimposable to that of the reference group. The same profiles were recorded in cohort B patients admitted with lower limb fractures or various types of trauma. This suggests that observations made on cohort A can be extrapolated to othertrauma patients. We recommend that serial measurements of CRP and TTR and of their ratio should be performed every 2 days to appropriately follow-up these patients.

Seronegative spondyloarthropathy initiated by physical trauma

We undertook this study to demonstrate the pattern of onset and the course of arthritis on the traumatised joint in spondyloarthropathy (SpA) initiated by physical trauma. Among 288 patients with SpA, 12 (4.2%) whose arthropathies were associated with trauma were reviewed retrospectively. There were seven patients with ankylosing spondylitis (AS), three with juvenile onset AS and two undifferentiated SpA. The type of trauma was direct injury to the joint and injuries at other sites, except in spinal surgery, for example. In eight cases the initial evidence of disease was peripheral arthritis. The disease first occurred in traumatised joints in five cases. Only three cases showed recurrent inflammatory episodes in the traumatised joints throughout the disease course. SpA initiated by trauma initially manifested as peripheral arthritis at the traumatised joints in about half of the cases. Inflammatory episodes preferentially involved other joints apart from the traumatised joints throughout the whole course of the disease.

[The dynamic of biochemical stress reaction inductors in various tactics for surgical treatment of patients with a combined trauma of cranium and lower limbs ]

In 31 patients after a craniocerebral trauma combined with a trauma of locomotor system (CCCT), and in 28 patients with only a limb fractures a time course (1, 3, 7, and 14 days) of biochemical stress reaction inductors (cortisol, serotonin, histamine, lipid peroxidation products) in various tactics of surgical treatment was studied. It was established that CCCT in a significantly stronger degree increases cortisol and lipid peroxidation products' levels than an isolated locomotor system trauma. An early postponed surgical intervention in lower extremities in CCCT results in the same increase in the biochemical stress reaction inductors as a late postpone surgical intervention in the lower extremities. In an early postponed osteosynthesis in CCCT patients, a mean term of hospital stay was 67 days, and in a late postponed one 117 days. The disability period was correspondingly 200 vs 315 days.

Humorally mediated thrombocytosis in major lower extremity trauma

Thrombocytosis in patients undergoing free tissue transfer for coverage of posttraumatic lower extremity defects may be associated with an increased incidence of microvascular thrombosis. Patients with isolated lower extremity trauma have an elevated platelet count that peaks approximately 2 weeks after injury. It is our theory that a humoral component of trauma sera is responsible for the induction of this thrombocytosis. Eight patients with isolated soft-tissue and bony trauma were included in the study. Serum was collected at baseline and throughout the study period. Platelet count, leukocyte count, hemoglobin concentration, and hematocrit were determined. Immunoassay for human interleukin-3 (IL-3), IL-6, and IL-11 as well as granulocyte macrophage colony stimulating factor (GM-CSF) were performed by solid-phase enzyme-linked immunosorbent assay. Balb-C mice were then injected intraperitoneally with the human trauma sera from all time points. Blood was collected at baseline and throughout the study period for determination of platelet count, hemoglobin, and hematocrit. Mean initial platelet count in the 8 human subjects was 152,000 per cubic millimeter with an average peak to 642,000 per cubic millimeter. IL-3, IL-11, and GM-CSF were not detectable in the serum of any patient. Elevated levels of IL-6 were detected in all patients in a nonspecific pattern. In the murine model, an early and late thrombocytosis was elicited. The early peak averaged 78.6% over baseline whereas the late peak average 81.0% over baseline. The induction by human trauma sera of an early and late thrombocytosis in this mouse bioassay supports the theory of humoral mediators. The humoral mediators are yet to be determined but may include IL-6.

[The characteristics of the blood lipid transport system in the disabled with lost lower extremities]

A comparative analysis of major blood lipoprotein values in 108 males aged 16-65 years with lower limbs amputations has shown a higher level of triglycerides (TG) and a reduced level of high density lipoprotein cholesterol (HDL C) in them than in control males with normal limbs. In the subgroup of patients who had undergone the amputation as a result of obliterative arterial disease, the TG level was the highest while HDL C the lowest; moreover, these values appeared to be the same as in the age-matched subgroup of patients with manifestations of atherosclerosis. In the subgroup of older men with posttraumatic lower limb amputations (aged 40-59 years) the TG and HDL C levels did not differ from the corresponding parameters in age-matched subgroup of healthy subjects, whereas young amputees (17-39 years) had the increased blood TG concentration and reduced level of HDL C and apolipoprotein AI. The conclusion is made: disability following limb amputation accompanied by restricted mobility, inadequate physical static efforts as well as by chronic psychological stress seem especially dangerous for young invalids because of associated lipoprotein profile changes which can be regarded as highly atherogenic.

[Experience with physiotherapy in a posttraumatic neurodystrophic syndrome of the extremities]

Combined pathogenetic treatment including physiotherapy, drugs, massage, exercise was tested in 98 patients with posttraumatic neurodystrophic syndrome in phase II and III. The responses achieved made it possible to recommend the above regimen for wide application in rehabilitation centers and clinics.

[Effects of combined therapy of traditional Chinese and Western medicine on C-reactive protein in post-debridement patients]

Closely monitoring whether the secondary infection in the patients of post-debridement occurred or not and appropriately treating these patients were the important ways to reduce the incidence of infection. Through estimating the level of the serum C-reactive protein (CRP) as the monitoring index of infection, dynamically observed the effect of the combined traditional Chinese and Western medicine therapy (TCM-WM) on CRP after debridement, as was compared with the effect of the Western medicine therapy (WM) group in which only the WM was administrated. The result showed that the levels of CRP decreased in both TCM-WM and WM group on 4th day after the operation, but the level of CRP in former group was lower than that in latter one, the difference was very significant (P < 0.001). So that, it was assumed that TCM-WM significantly excelled the WM on affecting the level of CRP and reducing the incidence of infection. It was suggested that CRP could be used as an effective and objective index to determine whether the secondary infection has happened and to assess the efficacy of some drugs.

Pulse oximetry in closed limb fractures

Recent sporadic reports have described the role pulse oximetry might play in monitoring trauma victims, and specifically in the assessment of patients with limb fractures where doubt exists concerning the adequacy of limb blood flow distal to the fracture after manipulation. The results of a prospective study to determine the changes in arterial oxygen saturation as shown by pulse oximetry before and after manipulation are presented. The results suggest that the pulse oximeter may be of use in confirming the presence or absence of adequate blood flow distal to a fracture, but that this information should be considered in the light of the clinical findings. The role of pulse oximetry in the early detection of a compartment syndrome complicating a closed limb fracture has yet to be determined.

Rhabdomyolysis following total hip arthroplasty

We report six cases of contralateral limb involvement during total hip arthroplasty including swelling of the gluteal muscle compartments, rhabdomyolysis, myoglobinuria, and sciatic nerve palsy. The risk factors for such complications include obesity, prolonged operative time, and positioning in the lateral decubitus position. The laboratory and clinical findings are consistent with a gluteal muscle crush-injury with consequent compartment syndrome. The patients should be treated conservatively as symptoms can be expected to resolve.

[Hemostatic changes after local exposure to low temperatures (frostbite)]

Hemostatic blood potential was studied in experiments on 400 rats, 25 dogs and in 120 patients, during changes of CNS reactivity after intraventricular injection of reserpine, adrenaline, and irritation of the thalamus ventromedial nucleus (VMN) or its destruction. CNS reactivity in dogs changed after intraarterial injections of acetylcholine, reserpine, heparin and fibrinolysin solutions. It was shown that activation of adrenergic structures of the hypothalamus by intraventricular adrenaline injections, or the hypothalamus VMN irritation, stimulated coagulation and depressed anticoagulation mechanisms of the blood, and increased hemostatic blood potential, that led to rejection of frostbitten tissues. Activation of the hypothalamus cholinergic structures by intraventricular injections of reserpine, destruction of the hypothalamus VMN, and intraarterial injections of acetylcholine, reserpine, heparin, fibrilysin and contrycal mixtures stimulated the blood anticoagulation mechanisms, decreased the hemostatic potential, led to retention of cryodestructed tissues.

[Importance of determining the blood sulfhydryl groups in fractures of the long tubular bones complicated by infection]

The work presents results of the investigation of the content of sulfhydryl groups in the blood of patients with fractures of long tubular bones. The content of sulfhydryl groups of blood was studied in 168 patients with open fractures. The author comes to a conclusion that the investigation of sulfhydryl groups of blood allows not only facilitating the evaluation of severity of patients in the pre- and postoperative period and detecting complications at early terms but also enables a timely correction of the disorders to be fulfilled.

Post-traumatic blood lipid changes and fat embolism. Relation of post-traumatic blood lipid changes and fat embolism syndrome

Serum cholesterol, triglycerides, phospholipids, and lipoprotein levels were studied by electrophoresis in 43 trauma patients with multiple fractures of the lower extremities and pelvis. Ten healthy volunteers were used for control studies. The fat embolism syndrome was diagnosed in eight of the 43 patients. The lipid values of all the trauma patients were lower than the control values. A decrease in cholesterol and phospholipids was observed in the fat embolism patients during 4 days; these changes were not observed in the other trauma patients. The triglycerides of all the trauma patients increased slowly over a period of 4 days. Changes in the lipoprotein fractions after the trauma were minor. An early increase in the alpha1 lipbrotein fraction was noted in the fat embolism patients simultaneously with a decrease in the pre-beta lipoprotein fraction; the values of the other trauma patients were at the control levels. Normalization was observed in 6 hours. The lipid concentrations of plasma and serum did not change with filtration with 1.2, 5, and 8mum Millipore filters. No differences were noted between the femoral and cubital vein samples.