Osteomyelitic Lesions Research Articles

Receptor Activator of Nuclear Factor kappa-B Ligand is Not Regulated During Chronic Osteomyelitis in Pigs

Bone loss is a major complication of osteomyelitis and from numerous in-vitro studies, it has been concluded that the bone lysis is caused by elevated expression of the receptor activator of nuclear factor κB ligand (RANKL), leading to increased osteoclast activity. However, we failed to find any relationship between bone loss and osseous RANKL expression in a porcine model of acute and chronic implant-associated osteomyelitis (IAO) due to Staphylococcus aureus or in chronic osteomyelitis lesions in slaughter pigs. Surprisingly, we found that the expression of RANKL was reduced during chronic bone infections. This is in line with the few studies conducted on human samples. A significant bone loss was observed in IAO lesions and in lesions from slaughter pigs, but with no indication of osteoclast involvement using histochemistry, immunohistochemistry for RANKL, receptor activator of nuclear factor kappa-B, osteoprotegerin and cathepsin K, and high-throughput quantitative real-time polymerase chain reaction on bone tissue from osteomyelitic lesions. A strong inflammatory response was seen in the infected animals and, therefore, we propose proteolytic enzymes induced by inflammation to be a major component of the bone loss. Furthermore, we found a significant upregulation of the IL26 gene in infected animals, which can inhibit RANKL-induced osteoclastogenesis, but has no homologue in mice. This finding emphasises that neither murine models nor in-vitro studies can mirror human disease development completely. The present study emphasises that the interactions between microorganisms, the immune system and bone cells in osteomyelitis are too complex to be accurately represented by an in-vitro model.

A comparison of ferumoxytol with gadolinium as contrast agents for the diagnostic magnetic resonance imaging of osteomyelitis

BackgroundFerumoxytol, an FDA-approved superparamagnetic iron oxide nanoparticle (SPION) preparation used for the treatment of iron deficiency anemia, is also known to be taken up by macrophages in areas of infection or inflammation, where it produces negative contrast changes on T2-weighted MR images. PurposeWe sought to compare Ferumoxytol-induced MRI contrast changes with those observed using standard-of-care Gadolinium in patients presenting with symptoms suggestive of osteomyelitis. SubjectsOut of eighteen enrolled patients, 15 had MR imaging with both ferumoxytol and gadolinium. Based on clinical and/or pathologic criteria, 7 patients were diagnosed with osteomyelitis, 5 patients had osteomyelitis ruled out, and in 3 patients a definitive diagnosis could not be made. Field strength1.5 Tesla. SequencesUsed included STIR, T1-weighted and T2-weighted spin echo. AssessmentThe mean contrast changes upon ferumoxytol and gadolinium administration were measured from lesion regions of interest and compared with control regions. Statistical testsStudent's t-test, propagation of errors. Data are reported as means ± S.E. ResultsThe mean contrast changes, ΔC, associated with a diagnosis of osteomyelitis were found to be ΔCFe = −2.7 ± 0.7 when Ferumoxytol and T2w imaging sequences were used and ΔCGd = +3.1 ± 1.1 (P < 0.001) when Gadolinium and a T1w imaging sequence was used. The MRI contrast changes for both agents correlated with systemic markers of inflammation, such as the erythrocyte sedimentation rate. In patients without osteomyelitis, no significant contrast changes were observed in T2-weighted, Ferumoxytol-contrasted MRI. The macrophages in osteomyelitic lesions were found to take up at least 16 times as much iron as benign bone marrow. Data conclusionWe conclude that in terms of its MRI diagnostic accuracy for osteomyelitis Ferumoxytol-contrasted MRI is a promising approach for diagnosing osteomyelitis that merits further study.

Blood perfusion in osteomyelitis studied with [15O]water PET in a juvenile porcine model

BackgroundOsteomyelitis is a serious disease which can be difficult to treat despite properly instituted antibiotic therapy. This appears to be related at least partly to degraded vascularisation in the osteomyelitic (OM) lesions. Studies of perfusion in OM bones are, however, few and not quantitative. Quantitative assessment of perfusion could aid in the selection of therapy. A non-invasive, quantitative way to study perfusion is dynamic [15O]water positron emission tomography (PET). We aim to demonstrate that the method can be used for measuring perfusion in OM lesions and hypothesize that perfusion will be less elevated in OM lesions than in soft tissue (ST) infection. The study comprised 11 juvenile pigs with haematogenous osteomyelitis induced by injection of Staphylococcus aureus into the right femoral artery 1 week before scanning (in one pig, 2 weeks). The pigs were dynamically PET scanned with [15O]water to quantify blood perfusion. OM lesions (N = 17) in long bones were studied, using the left limb as reference. ST lesions (N = 8) were studied similarly.ResultsPerfusion was quantitatively determined. Perfusion was elevated by a factor 1.5 in OM lesions and by a factor 6 in ST lesions.ConclusionsBlood perfusion was successfully determined in pathological subacute OM lesions; average perfusion was increased compared to that in a healthy bone, but as hypothesized, the increase was less than in ST lesions, indicating that the infected bone has less perfusion reserve than the infected soft tissue.

Post Mortem Leukocyte Scintigraphy in Juvenile Pigs with Experimentally Induced Osteomyelitis.

We have previously demonstrated that 111In-labeled autologous leukocyte scintigraphy is able to detect osteomyelitis in living juvenile pigs. In animal research studies, it may well be an advantage if the animals could be scanned after euthanasia. Applying traditional scanning of living animals to euthanized animals will render anaesthesia unnecessary and be ideal for obtaining good and reliable scans for the correct interpretation of imaging afterwards, since the animals do not move. The autologous leukocytes of the pigs were collected, marked with 111In, and reinjected into the pigs and allowed for homing to the site of infections as usual while the pigs were alive. In this study, we demonstrate that it is possible to perform SPECT/CT with 111In-labelled autologous leukocytes almost 24 hrs after euthanasia with the same detectability of osteomyelitic lesions as in living pigs (78% versus 79%). The pigs in this study had exactly the same experimental conditions as the living pigs and were examined in parallel with the living pigs except for euthanasia prior to the leukocyte scan and that no PET/CT scans were performed.

Nonbacterial osteitis in children: data of a German Incidence Surveillance Study

To analyse the incidence, clinical presentation, laboratory and radiological findings, as well as diagnostic approaches and therapeutic procedures in paediatric patients suffering from nonbacterial osteitis. A nationwide incidence survey was conducted from 2006 to 2008 through monthly contacts with all German paediatric and paediatric-orthopaedic hospitals. Children with osteomyelitic bone lesions newly diagnosed as suffering from nonbacterial osteitis were identified. Cases were assessed using a questionnaire to be filled in by the treating physician containing information on time since first symptoms, associated diseases, diagnostic procedures, localization of lesions, complications, laboratory and histological results, and treatment. Nonbacterial osteitis was newly reported in 148 children. The annual incidence was estimated at 0.4 per 100,000 children. Mean manifestation age was 11.4 years (SD 3.2); 99 children (67%) were girls. Palmoplantar pustulosis was observed in 8 (6%). Unifocal manifestations were seen in 50 (34%) patients. Of all patients with vertebral involvement (15%), 9% suffered from vertebral fractures. Bone biopsies were taken in 79 (53%) patients. Nonbacterial osteitis is an auto-inflammatory disorder resulting in at least 60 new paediatric cases/year in Germany. Spinal lesions and complications are frequently observed, even at first diagnosis.

ＳＰＩＯ造影剤投与後の骨髄におけるＭＲ信号を捉えるための評価法

Super paramagnetic iron oxide (SPIO) is taken up in the bone marrow and lymph nodes, as well as by the liver. Focusing on the intervertebral disks, which are unaffected by contrast effects, we examined the relationship between magnetic resonance image (MRI) signal intensity after SPIO uptake in the vertebral body and intervertebral disks and investigated MRI signal intensity in bone marrow metastases and osteomyelitic (inflammatory) lesions after SPIO uptake by bone marrow. The lumbar spine was imaged in 5 healthy volunteers (age range, 26-48 years). A specified amount of SPIO was administered intravenously, and signal intensities before and after administration were measured. The signal intensity ratio with respect to the value before administration was calculated, and quantitative signal analysis was conducted. A similar investigation was performed in patients with bone metastasis and osteomyelitis. As a result of the metastasis, the signal intensity ratio showed a low value in comparison with normal marrow, and the osteomyelitis showed a high value in comparison with normal marrow. We report the usefulness of evaluations of changes in marrow signal intensity using SPIO in MRI.

Mycobacterium arosiense sp. nov., a slowly growing, scotochromogenic species causing osteomyelitis in an immunocompromised child

A yellow-pigmented, scotochromogenic, slowly growing mycobacterial strain, designated T1921(T), was isolated from the disseminated osteomyelitic lesions of a 7-year-old child with an underlying partial gamma interferon receptor alpha-1 deficiency. Hybridization by the line probe assay indicated the presence of a Mycobacterium species. Sequencing of the 16S rRNA gene, the internally transcribed spacer (ITS) region and the hsp65 and rpoB genes revealed that strain T1921(T) could be differentiated from all recognized species of the genus Mycobacterium. Phylogenetic analysis based on the 16S rRNA gene indicated that strain T1921(T) was related most closely to Mycobacterium intracellulare, whereas analysis based on the ITS and hsp65 and rpoB genes indicated that it was most closely related to Mycobacterium avium. Phenotypic tests were not able to differentiate strain T1921(T) from similar slowly growing mycobacteria. Strain T1921(T) is considered to represent a novel species of the genus Mycobacterium, for which the name Mycobacterium arosiense sp. nov. is proposed. The type strain is T1921(T) (=DSM 45069(T) =ATCC BAA-1401(T)).

Poster 2, Acne fulminans: part of the spectrum of SAPHO

A 13‐year‐old boy was admitted to hospital with severe back pain and systemic upset. He had commenced isotretinoin 25 mg (0·5 mg kg–1) daily 17 days previously for severe acne unresponsive to oral erythromycin. Isotretinoin was stopped after 4 days due to severe lower back pain. On admission, he was unable to mobilize and the pain was uncontrolled with oral morphine sulphate. Investigations showed leucocytosis and neutrophilia. Magnetic resonance imaging of the vertebrae showed multiple areas of high signal consistent with an inflammatory process such as osteomyelitis. Oral prednisolone 40 mg daily and ibuprofen controlled the pain within 2 days. Sulfasalazine (1 g twice daily) was commenced 10 days later. The re‐introduction of isotretinoin 5 mg daily 12 days after admission precipitated severe back pain, necessitating 3 days of intravenous methylprednisolone. The oral prednisolone dose has been reduced over 6 weeks and stopped. The acne is currently controlled with clindamycin, although there is marked scarring. Acne fulminans is a rare condition characterized by sudden onset of severe acne and systemic features such as fever, leucocytosis and arthralgia.1 Osteomyelitic lesions are a recognized feature. In 1987, the term SAPHO (synovitis, acne, pustulosis, hyperostosis, osteitis) syndrome was proposed to describe a clinical entity with skin, joint and bone manifestations. Associated skin conditions include severe acne, psoriasis and palmoplantar pustulosis. Reported sites of osteoarticular involvement include the anterior chest wall, vertebrae, pelvis and mandible.2 Our patient clearly has acne fulminans and fulfils the criteria for SAPHO syndrome. We believe this condition will be increasingly recognized by dermatologists. 1 Karvonen S. Acne fulminans: report of clinical findings and treatment of twenty‐four patients. J Am Acad Dermatol 1993; 28:572–9. 2 Hayem G, Bouchaud‐Chabot A, Benali K et al. SAPHO syndrome: a long‐term follow‐up study of 120 cases. Semin Arthritis Rheum 1999; 29:159–71.

Comparison between Leukoscan® (Sulesomab) and Gallium-67 for the diagnosis of osteomyelitis in the diabetic foot

The diagnosis of osteomyelitis in patients with diabetic foot is difficult both clinically and radiologically. An early diagnosis is crucial to optimize therapeutic strategy. Among the diagnostic methods currently used, scintigraphy with ex-vivo labelled white blood cells is the gold standard, but cannot be performed in all centers; therefore 67Gallium citrate (67Ga) imaging in combination with a bone scintigraphy is still widely used. The results of imaging 24 diabetic patients with 31 suspected osteomyelitic lesions using the antigranulocyte Fab' fragment (Sulesomab or LeukoScan or immunoscintigraphy) were prospectively compared with results from the bone scan coupled with 67Ga. The diagnosis of osteomyelitis was confirmed by either biopsy or follow-up, radiological imaging and clinical outcome. Sulesomab correctly identified 12 of 18 osteomyelitic lesions while 67Ga was able to detect only 8 of 18. Therefore the sensitivity is 67% for Sulesomab and 44% for 67Ga. Among the 13 non-osteomyelitic lesions imaging with Sulesomab was able to rule out infection in 11 cases and 67Ga in 10 cases. The specificity is therefore 85% for Sulesomab and 77% for 67Ga. Image interpretation for Sulesomab in this group of patients is occasionally suboptimal when imaging is performed at 3 hours post injection. High vascular background in the early images may obscure infection especially in small bones. Practically, scintigraphy with Sulesomab is fast and simple due to ease of labeling, no ex-vivo handling of blood, low radiation and provides rapid diagnosis. The diagnosis of osteomyelitis obtained by the antibody fragment scintigraphy influences the management (guided biopsy) and therapy. In several patients, imaging with Sulesomab was able to rule out osteomyelitis, helping to avoid useless antibiotic therapy and its associated side effects.

Establishment of rat model of acute staphylococcal osteomyelitis: relationship between inoculation dose and development of osteomyelitis

Many animal models of acute and chronic osteomyelitis have been developed. In these models, osteomyelitic lesions are induced using sclerosing agents and foreign bodies with bacterial strains. In the present rat model, these sclerosing agents were not used. We assessed the relationship between inoculation dose and histological, radiological, and microbiological changes in the acute phase (1 week after inoculation) using this rat osteomyelitis model. An experimental rat model of acute osteomyelitis was developed by direct inoculation of the virulent strain BB of Staphylococcus aureus into tibial bone without sclerosants. To examine the relationship between the inoculation dose of the bacteria and the progression of the osteomyelitis, the inoculated lesions were assessed for changes in histological, radiological, and bacteriological parameters at 1 week after infection. Serial dilutions of the bacteria [6 x 10(1) to 6 x 10(5) colony-forming units (CFU)/5 microl] suspended in saline or saline alone were inoculated into the proximal metaphysis of the tibia. Development of significant histological and radiological signs of osteomyelitis required an inoculum of at least 6 x 10(3) CFU/5 microl. The number of viable bacteria at the lesion reached a maximum of 6 x 10(3) CFU/5 microl. These results suggest that strain BB induces the development of acute staphylococcal osteomyelitis with clear infective destruction in the tibia, and that our model may be applied to the identification of virulence factors in studies of posttraumatic osteomyelitis.

Hematogenous osteomyelitis in adults

Hematogenous osteomyelitis (HOM) in adults is a very rare event in industrialised countries. However, in tropical regions the morbidity of HOM is more important, primarily due to the impact of sickle cell disease, thalassemia, HIV-infection and tuberculosis. HOM is most commonly caused by pyogenic bacteria and mycobacteria, but infections by fungi, viruses and parasites must also be considered. In spite of modern diagnostic procedures such as nuclear and magnetic resonance imaging, the histopathologic and microbiologic examination of bone remains the gold standard for diagnosing OM. Other diagnoses should also be considered. Nonbacterial osteomyelitic lesions (plasmacellular OM, sclerosing OM, SAPHO syndrome) as well as acute leukemia, malignant bone tumors (i.e., Ewing's sarcoma, osteosarcoma) are conditions with similar presentations. Acute HOM is best managed by appropriate antibiotic therapy. In case of failure and in chronic HOM, surgical debridement is mandatory.

(99m)Tc-E-selectin binding peptide for imaging acute osteomyelitis in a novel rat model.

In the present study, (99m)Tc-radiolabelled E-selectin binding peptide ((99m)Tc-IMP-178) was investigated for its potential to image acute pyogenic osteomyelitis in a new animal model. Intraindividual comparisons were performed using an irrelevant peptide ((99m)Tc-IMP-100) to demonstrate specificity. An acute pyogenic osteomyelitis was induced by injecting 0.05 ml of 5% sodium morrhuate and 5x10(8) CFU of Staphylococcus aureus into the medullary cavity of the right tibia in 16 rats. Sixteen additional rats served as untreated controls. Whole-body imaging of pyogenic (n=4) and untreated (n=4) animals was performed continuously during the first 8 h (12 MBq i.v. of (99m)Tc-IMP-178 and (99m)Tc-IMP-100 for control), and one further single image was acquired after 16 h p.i. Tissue biodistribution studies were performed in 12 rats with an acute pyogenic osteomyelitis and in 12 untreated rats 1, 4 and 24 h after injection. Data of the histological/radiological and haematological investigations were obtained in all animals. Histopathologically, 15 of 16 treated rats (93%) developed an acute pyogenic osteomyelitis showing a major infiltration of the bone marrow by polymorphonuclear leukocytes as well as the formation of sequestra. Haematologically, the number of leukocytes increased by 100%, the lymphocytes by 11% and the granulocytes decreased by 39%. After i.v. injection, (99m)Tc-IMP-178 rapidly cleared from the body resulting in good scintigraphic target-to-background (T/B) ratios. The highest uptake of the tracer in the pyogenic bone was observed at 60 min p.i. (0.43+/-0.02% ID.g-1 for (99m)Tc-IMP-178 and 0.30+/-0.02% ID.g-1 for (99m)Tc-IMP-100), resulting in a higher osteomyelitis-to-healthy collateral ratio with T/B of 2.40+/-0.65 ((99m)Tc-IMP-178) compared with 1.85+/-0.48 ((99m)Tc-IMP-100). No adverse reactions were seen after injection of (99m)Tc-IMP-178. (99m)Tc-IMP-178 allows imaging of an acute osteomyelitic lesions, presumably by interaction of (99m)Tc-IMP-178 with activated upregulated vascular endothelium.

99Tcm-citrate

99Tcm-citrate has been shown to incorporate irreversibly in the skeleton with a biodistribution different to that on a conventional bone scan. The aims of this study were to confirm the bone-imaging properties of 99Tcm-citrate, to identify the variabilities influencing its skeletal uptake, to compare its uptake in bone with that of 99Tcm-MDP and to assess its possible role in bone scintigraphy. Appropriate animal and human studies (n = 45) were conducted. The 3 h lesion-to-bone ratio of 99Tcm-citrate was compared with that of 99Tcm-MDP in more than 150 lesions, including osteoblastic sites (Group A), lesions undergoing treatment or healing (Group B), and degenerative or old healed lesions (Group C). The uptake ratio was classified as concordant (< 20% variation), mildly discordant (20-50% variation) or significantly discordant (> 50% variation). Animal experiments showed most bone uptake of 99Tcm-citrate when prepared at a pH of 6.0-6.5. The two radiopharmaceuticals appeared to compete for bone uptake, suggesting related but different sites of bone accumulation. The 99Tcm-citrate/99Tcm-MDP uptake ratio in Group A was concordant (mean +/- S.D. = 0.92 +/- 0.15), while Group C lesions had a significantly lower 99Tcm-citrate/99Tcm-MDP uptake ratio (0.34 +/- 0.24, P < 0.01). A comparison of Group B lesions showed wide variation in intensity and area of involvement in many lesions (uptake ratio < 0.5 or > 1.5 in 13 of 30 sites). We conclude that 99Tcm-citrate has a different site of bone localization than phosphonates, possibly in the organic matrix. Although its skeletal uptake is lower than that of 99Tcm-MDP, it may have better specificity in differentiating osteoblastic from degenerated or healed bony lesions, and therefore be useful in predicting healing of bone secondaries, fractures or osteomyelitic lesions.

Subacute Multiple-Site Osteomyelitis Caused by Borrelia burgdorferi

In a pediatric case of severe multiple-site osteomyelitis caused by Borrelia burgdorferi, the presence of spirochetes in a bone lesion was documented both by culture and by the polymerase chain reaction (PCR). Positive PCR results were also obtained with culture fluid yielding spirochetal growth and with acute-phase serum. Although the disease evidently was a late manifestation of Lyme borreliosis, antibodies to B. burgdorferi were low in titer and were restricted to the IgM class. The distribution of osteomyelitic lesions in multiple bones and the positive PCR results obtained with serum argue for hematogenous spread of the spirochetes. Before the specific diagnosis was established, the patient received several potent antimicrobial drugs, without a favorable outcome. In contrast, therapy with ceftriaxone led to a rapid cure that persisted thereafter. We conclude that infection due to B. burgdorferi must be considered a possible cause of subacute pediatric osteomyelitis.

Chronic staphylococcal osteomyelitis: a new experimental rat model

A rat model of chronic staphylococcal osteomyelitis was developed. Fibrin glue (5 microliters) and Staphylococcus aureus (2 x 10(6) CFU/5 microliters) were inoculated into the proximal metaphysis of the tibia. The rats were killed at intervals of between 1 and 6 months, and the tibias were removed. Induced lesions were evaluated by radiographic, macroscopic, and histological examinations and bacterial counts. Roentgenograms revealed osteomyelitis in more than 90% of the tibias. Gross bone pathology revealed skeletal deformation, new bone formation, abscesses, and draining skin fistulas in more than 80% of cases. Histological examination revealed osteomyelitis in more than 90% of cases, and bacterial counts were positive in 86% of cases. Only fibrin glue (5 microliters) was inoculated into controls. Controls showed no osteomyelitic lesions, and counts were negative in seven of eight control tibias. The main feature of this model is the use of fibrin glue instead of the sclerosing agents and foreign bodies used in other models. The model reproduces lesions similar to those of human posttraumatic osteomyelitis and can be reliably used in pathophysiological and therapeutic studies.

Postextraction osteomyelitis in a bone marrow transplant recipient

This report describes a case of mandibular osteomyelitis after a dental extraction in a patient who subsequently underwent bone marrow transplantation (BMT) for lymphoblastic lymphoma. Surgical guidelines consistent with National Cancer Institute recommendations were followed for the extraction, which was performed before initiation of the myelosuppressive conditioning regimen. However, moderate tenderness developed at the extraction site beginning 10 days after marrow infusion. On day 26 the patient became febrile and blood culture-positive for Staphylococcus epidermidis. Radiographs exposed on day 28 demonstrated changes consistent with low-grade osteomyelitis, including diffuse loss of lamina dura and an irregular osseous rarefaction extending 1 cm posterior to the extraction site. Although the indwelling Hickman catheter was the presumed source for bacteremia, clinical and radiographic data led to consideration of mandibular osteomyelitis as an alternative cause. Characteristics of this infection in BMT recipients are reviewed. Recommendations for dental extractions and prophylactic antibiotic regimens for catheterized BMT recipients are also discussed. Although mandibular osteomyelitic lesions are not common in profoundly immunosuppressed BMT recipients, prompt recognition and treatment are essential when the disease occurs.

A comparison of exotoxin patterns of Staphylococcus aureus strains isolated from osteomyelitic lesions with those from topical infections

A comparison of exotoxin patterns of <i>Staphylococcus aureus</i> strains isolated from osteomyelitic lesions with those from topical infections

Treatment of infected nonunion of the tibia with electrical stimulation combined with local muscle flaps

The widely documented treatment of nonunion with various clinical applications of electrical stimulation has met with an excellent success rate (70–93.6%). Local muscle flaps are widely accepted in the treatment of osteomyelitic lesions, and in our departments a combined, one-stage application of electrical stimulation with local muscle flap has been used on six cases of infected nonunion of the tibia with excellent results.

Scintigraphic Imaging of Osteomyelitic Lesions in Four Dogs

Scintigraphic Imaging of Osteomyelitic Lesions in Four Dogs

Osteomyelitis after operative fracture treatment. A report of 62 cases treated with radical surgery and lincomycin (Lincocin).

During the years 1967--1975 a total of 62 patients were treated for postoperative osteomyelitis. The lower extremities had been fractured in 89 per cent of the cases and 54 per cent were closed injuries. The fractures, mostly caused by traffic accidents and falls, had been immobilized by plates in 30 and by intramedullary nails or pins in 25 patients. Staphylococcus aureus was cultured in 80 per cent, 68 per cent of them were resistant to penicillin, but in 84 per cent the organisms were highly lincomycin sensitive and only three patients with four osteomyelitic lesions presented lincomycin resistance. The treatment consisted chiefly of sequestrectomies and saucerizations supported by 3--12 months of lincomycin treatment. In 30 operations a closed irrigation-suction technique was used, perfusing the wound with lincomycin solution. Stable implants should be left in place until the fracture is clinically solid whereas unstable osteosyntheses should be replaced by rigid internal or extraskeletal fixation. At follow-up, the results were judged as good in 74 per cent, fair 8 per cent and poor 18 per cent. The amputation rate was 13 per cent. Plates should not be used in the treatment of comminuted tibial fractures with considerable soft tissue damage.