Short- to mid-term results of metallic press-fit radial head arthroplasty in unstable injuries of the elbow.

We assessed the short- to mid-term survival of metallic press-fit radial head prostheses in patients with radial head fractures and acute traumatic instability of the elbow. The medical records of 42 patients (16 males, 26 females) with a mean age of 56 years (23 to 85) with acute unstable elbow injuries, including a fracture of the radial head requiring metallic replacement of the radial head, were reviewed retrospectively. Survival of the prosthesis was assessed from the radiographs of 37 patients after a mean follow-up of 50 months (12 to 107). The functional results of 31 patients were assessed using range-of-movement, Mayo elbow performance score (MEPS), Disabilities of the Arm, Shoulder and Hand (DASH) score and the RAND 36-item health survey. At the most recent follow-up 25 prostheses were still well fixed, nine had been removed because of loosening, and three remained implanted but were loose. The mean time from implantation to loosening was 11 months (2 to 24). Radiolucent lines that developed around the prosthesis before removal were mild in three patients, moderate in one and severe in five. Range of movement parameters and mass grip strength were significantly lower in the affected elbow than in the unaffected side. The mean MEPS score was 86 (40 to 100) and the mean DASH score was 23 (0 to 81). According to RAND-36 scores, patients had more pain and lower physical function scores than normal population values. Loosening of press-fit radial head prostheses is common, occurs early, often leads to severe osteolysis of the proximal radius, and commonly requires removal of the prosthesis.

Is the biofilm formation and slime producing ability of coagulase-negative staphylococci associated with the persistence and severity of intramammary infection?

Biofilm and slime formation assists bacteria in avoiding the host immune defence and antimicrobial therapy. It is suspected to affect the severity or persistence of mastitis caused by coagulase-negative staphylococci (CNS), which are a common cause of bovine mastitis. The phenotypic biofilm formation ability of 244 CNS isolates (199 isolates from bovine mastitis and 52 type and reference strains) was investigated with a tissue culture plate (TCP) assay and fluorescent in situ hybridization (FISH). Slime production of the strains was assessed using Congo red agar (CRA) plates. Additionally, genes encoding the adhesion proteins MSCRAMM (microbial surface components recognizing adhesive matrix molecules) and biofilm-associated proteins (bap) were detected. The severity of intramammary infection (IMI) in mastitis from which the isolates originated was measured with milk N-acetyl-ß-D-glucosaminidase (NAGase) activity. One-third of isolates from mastitis produced biofilm when analysed with TCP or FISH. The kappa test value, measuring the agreement between two tests, differed between CNS species. Slime production was less frequent for isolates of the common mastitis species Staphylococcus chromogenes (0.2% of isolates produced slime) and Staphylococcus simulans (3.5%) compared to Staphylococcus epidermidis (40%). No association was found between the phenotypic ability to form biofilm and the persistence of IMI or severity of mastitis. Slime production was rare in isolates originating from IMI. Only 12.7% of isolates from persistent IMI and 1.8% of isolates from spontaneously eliminated IMI produced slime. The eno gene encoding laminin-binding protein was most frequently detected among the isolates from mastitis, 75% of them having this gene. Only a few other MSCRAMM genes were detected.

Epidemiology and seasonal variation of distal radius fractures in Oulu, Finland.

UNLABELLED: The purpose of this study was to assess changes in epidemiology and reasons for wintertime excess of distal radius fractures in Oulu, Finland. Our results showed that age-specific incidence of distal radius fractures in elderly women in Finland has increased compared with a previous study. Slippery pavement surfaces assessed by a new meteorological model partly explained wintertime excess of fractures, but factors beyond weather are contributing to seasonality. INTRODUCTION: In this report, we describe the epidemiology and seasonal variation of distal radius fractures in Oulu, Finland, with a focus on the effect of weather and slippery pavement conditions. METHODS: Records of patients aged ≥16 years living in Oulu with a distal radius fracture during the year 2008 were reviewed. Demographic data and details of the injury were assessed from medical records, and fractures were classified according to AO classification. Population data for Oulu during the year 2008 were used to calculate crude incidence as well as sex- and age-specific incidence rates. The number of wintertime fractures was compared with those related to pavement surface slipperiness using a unique weather and pavement condition model of the Finnish Meteorological Institute. RESULTS: The crude incidence was 258/100,000 person-years. Sex- and age-specific incidence rates rose to 1,107/100,000 person-years for females and 466/100,000 person-years for males aged ≥80 years. Poisson regression analysis showed that the number of fractures was 2.5 (95% confidence interval (CI), 1.6 to 4.0; P < 0.001) times greater on slippery winter days compared with non-winter days whereas on normal winter days fractures were 1.4 (95% CI, 1.1 to 1.9; P = 0.01) times greater. Both low- and high-energy injuries resulted in similar fracture patterns by AO classification. CONCLUSIONS: Our results suggest that the epidemiology of distal radius fractures in elderly women in Finland has changed compared with a previous study. Weather analysis showed that the slipperiness of the pavement could partly explain the wintertime excess of distal radius fractures.

Bioactive glass S53P4 as bone graft substitute in treatment of osteomyelitis.

Bioactive glass (BAG)-S53P4 is an osteoconductive bone substitute with proven antibacterial and bone bonding properties. In a multicentre study 11 patients with verified chronic osteomyelitis in the lower extremity and the spine were treated with BAG-S53P4 as a bone substitute. The cavitary bone defect and the surrounding of a spinal implant were filled with BAG-S53P4. The most common pathogen causing the infection was Staphylococcus aureus. The mean follow-up was 24 months (range 10-38). BAG-S53P4 was well tolerated. Nine patients healed without complications. One patient who achieved good bone formation sustained a superficial wound infection due to vascular problems in the muscle flap, and one patient had an infection due to a deep haematoma. This study shows that BAG-S53P4 is a good and well-tolerated bone substitute, and can be used in treatment of osteomyelitis with good primary results.

Functional comparison of the dynamic hip screw and the Gamma locking nail in trochanteric hip fractures: a matched-pair study of 268 patients.

The aim of this prospective matched-pair (age, sex, fracture type, residential status, and walking ability at fracture) study was to analyse the short-term outcome after Gamma nail (GN) and dynamic hip screw (DHS) fixation, focusing especially on functional aspects (Standardised Audit of Hip Fractures in Europe [SAHFE] hip fracture follow-up forms), reoperations, and mortality. Both groups consisted of 134 patients. DHS and GN groups did not differ significantly with respect to location of residence at 4 months or returning to the prefracture dwelling (78% vs. 73%, P = 0.224). The change in walking ability at 4 months compared to prefracture situation was better in the DHS group (p = 0.042), although there was no difference in the change of use of walking aids. The frequency of reoperations during the first year was somewhat lower in the DHS group (8.2% vs. 12.7%, p = 0.318). Mortality was lower in the DHS group both at 4 months (6.0% vs. 13.4%, p = 0.061) and 12 months (14.9% vs. 23.9%, p = 0.044). Although walking ability was better and mortality lower in the DHS group, both methods are useful in the treatment of trochanteric femoral fractures.

RhBMP-7 accelerates the healing in distal tibial fractures treated by external fixation.

External fixation of distal tibial fractures is often associated with delayed union. We have investigated whether union can be enhanced by using recombinant bone morphogenetic protein-7 (rhBMP-7). Osteoinduction with rhBMP-7 and bovine collagen was used in 20 patients with distal tibial fractures which had been treated by external fixation (BMP group). Healing of the fracture was compared with that of 20 matched patients in whom treatment was similar except that rhBMP-7 was not used. Significantly more fractures had healed by 16 (p=0.039) and 20 weeks (p=0.022) in the BMP group compared with the matched group. The mean time to union (p=0.002), the duration of absence from work (p=0.018) and the time for which external fixation was required (p=0.037) were significantly shorter in the BMP group than in the matched group. Secondary intervention due to delayed healing was required in two patients in the BMP group and seven in the matched group. RhBMP-7 can enhance the union of distal tibial fractures treated by external fixation.

Transgenic cows that produce recombinant human lactoferrin in milk are not protected from experimental Escherichia coli intramammary infection.

This is the first study describing an experimental mastitis model using transgenic cows expressing recombinant human lactoferrin (rhLf) in their milk. The aim of the study was to investigate the concentrations in milk and protective effects of bovine and recombinant human lactoferrin in experimental Escherichia coli mastitis. Experimental intramammary infection was induced in one udder quarter of seven first-lactating rhLf-transgenic cows and six normal cows, using an E. coli strain isolated from cows with clinical mastitis and known to be susceptible to Lf in vitro. Clinical signs were recorded during the experimental period, concentrations of human and bovine Lf and indicators of inflammation and bacterial counts were determined for milk, and concentrations of acute-phase proteins and tumor necrosis factor alpha were determined for sera and milk. Serum cortisol and blood hematological and biochemical parameters were also determined. Expression levels of rhLf in the milk of transgenic cows remained constant throughout the experiment (mean, 2.9 mg/ml). The high Lf concentrations in the milk of transgenic cows did not protect them from intramammary infection. All cows became infected and developed clinical mastitis. The rhLf-transgenic cows showed milder systemic signs and lower serum cortisol and haptoglobin concentrations than did controls. This may be explained by lipopolysaccharide-neutralizing and immunomodulatory effects of the high Lf concentrations in their milk. However, Lf does not seem to be a very efficient protein for genetic engineering to enhance the mastitis resistance of dairy cows.

Survival, growth and persistence under farm conditions of a Lactobacillus plantarum strain inoculated into liquid pig feed.

AIMS: To investigate the survival and persistence of Lactobacillus plantarum REB1 in the fermentation process of liquid pig feed on a working farm in standard production conditions. METHODS AND RESULTS: Two feed types, a control diet [nonfermented liquid feed (NFLF)] and a fermented diet [fermented liquid feed (FLF)], were compared. A rifampicin-resistant mutant L. plantarum REB1-Rif was used to initiate the fermentation of the feed. Inoculation with the experimental strain was repeated one or two times per week throughout the three month growing period. Four microbial groups were followed using standard microbiological techniques, as well as pH. Lactic acid bacteria (LAB) counts were high already at the beginning in FLF, while it took nine days to reach the corresponding LAB levels in NFLF. Yeasts were stable in FLF, whereas in NFLF there were occasional high counts during the first week. The numbers of Enterobacteriaceae were low, although in NFLF they were variable. The average pH in NFLF was 4.5 and 4 in FLF. CONCLUSIONS: The inoculation of L. plantarum REB1-Rif provided a LAB population of log 9 colony forming units (CFU) ml(-1) from the first feeding day, stable numbers of yeast and pH, and a drastic reduction of Enterobacteriaceae. SIGNIFICANCE AND IMPACT OF THE STUDY: The inoculation by L. plantarum REB1-Rif offered a FLF microbiologically stable from the first week in actual production conditions.

Local pressures in the subacromial space.

We recorded pressures in the subacromial space with various degrees of humeral abduction. The recordings were made during open surgery and under general anaesthesia using a 2-mm-thick piezo-electric pressure transducer. The pressures were recorded in 14 patients with shoulder impingement syndrome (Neer's stage II) and in eight patients with acromioclavicular dislocation serving as controls. The pressures were higher in the impingement group than in the control group. In both groups the highest pressures were recorded antero-laterally under acromion. In patients with impingement syndrome, the pressures increased significantly with abduction.

Involvement of the subacromial bursa in impingement syndrome of the shoulder as judged by expression of tenascin-C and histopathology.

Our aim was to evaluate bursal involvement at different stages of the impingement syndrome as judged by conventional histopathological examination and expression of tenascin-C, which is known to reflect active reparative processes in different tissues and disorders. Samples of subacromial bursa were taken from 33 patients with tendinitis, 11 with a partial tear and 18 with a complete tear of the rotator cuff, and from 24 control shoulders. We assessed the expression of tenascin-C, the thickness of the bursa, and the occurrence and degree of fibrosis, vascularity, haemorrhage and inflammatory cells. The expression of tenascin-C was significantly more pronounced in the complete tear group (p < 0.001) than in the partial tear, tendinitis or control groups. It was more pronounced in the tendinitis group than in the control group (p = 0.06), and there was more fibrosis in all the study groups than in the control group. The changes in the other parameters were not equally distinctive. Expression of tenascin-C did not correlate with the conventional histopathological parameters, suggesting that these markers reflect different phases of the bursal reaction. Tenascin-C seems to be a general indicator of bursal reaction, being especially pronounced at the more advanced stages of impingement and this reaction seems to be an essential part of the pathology of impingement at all its stages.

Supraspinatus outlet view in the diagnosis of stages II and III impingement syndrome.

PURPOSE: To compare supraspinatus outlet view (SOV) findings at different stages of the impingement syndrome (IS) with findings in asymptomatic age- and sex-matched controls. MATERIAL AND METHODS: Pre-operative SOVs were obtained of 37 shoulders of patients scheduled for unilateral open repair of a full-thickness rotator cuff tear (stage III IS) and 74 shoulders of patients scheduled for open (n=46) or arthroscopic (n=28) acromioplasty for tendinitis (stage II IS). Each view of a patient's shoulder was paired with a control view obtained from an age- and sex-matched person with no shoulder problems (n=111). RESULTS: There were no significant differences in acromial morphology as evaluated on the scale devised by BIGLIANI et al. or in the tilt, slope or length of the acromion between the study groups and their controls. However, hooked acromion seemed to be more common in the patients. The thickness of the anterior part of the acromion at the tendinitis stage and the acromial angle at the tear stage of IS were the only parameters that showed significant differences between patients and controls. CONCLUSION: Variation of the morphology of the acromion as evaluated on a basis of the SOV is associated with IS, but the association is weak and its value in the diagnosis of IS is therefore only as an adjunctive to other diagnostic modalities.

Occurrence of Escherichia coli O157 in Finnish cattle.

Bovine faecal samples were collected during June-December 1997 at 14 major abattoirs slaughtering cattle in Finland. Escherichia coli O157 was isolated from 19 of the 1448 samples (1.31%) after enrichment and immunomagnetic separation (IMS). The positive faecal isolates originated from 16 farms and eight abattoirs. The occurrence of E. coli O157 was highest in July (8/204; 3.92%) and September (6/244; 2.46%). No E. coli O157 was detected in November and December, nor from the faecal samples from the northernmost region where cattle density is low. All of the isolates carried the eae gene and showed the enterohaemolytic phenotype. All except one were motile and had the flagella antigen H7. Seventeen of the isolates were positive for stx(2) gene and one carried both the stx(1) and stx(2) genes. Of the 17 isolates with stx genes, 16 were verocytotoxin-positive in a reversed passive latex agglutination test after polymyxin extraction but only eight without extraction. The isolates belonged to 10 different pulsed-field gel electrophoresis (PFGE) patterns. The most common PFGE pattern (1.42) was detected in eight isolates (42.1%). Four PFGE patterns (1.1; 1.6; 1.12; 1.14) were identical with those isolated from humans in Finland, suggesting that at least some human E. coli O157 infections may be of bovine origin.

Fish quality assessment with ion mobility based gas detector.

Measurement of the mixture of extractable volatile compounds of the gills of vendace was used in the fish freshness evaluation (Coregonus albula L.). MGD-1 gas detector was used for the detection of volatile compound profiles of hexane extracts of gills. The measuring principle of MGD-1 is ion mobility distribution and is based on IMCELL technique. A 2.5 microl sample of hexane extract was heated on a ceramic plate and the vapour was carried with a constant flow (2.5 I/min) of active carbon filtered air to the detector. The ion mobility distribution spectrum was measured every 1 second for 2 minutes. For reference, the microbial counts of gills, ATP-breakdown products (K-value) of fish flesh, electrical properties (Torrymeter scores) of fish skin and sensory evaluation scores were measured. The ion mobility distribution profiles of gills changed significantly during the 7 days storage period The findings related to freshness evaluation were supported by the reference methods. There is, however, a seasonal difference in the freshness probably due to seasonal variation of microbial flora. Besides the evaluation of fish quality, ion mobility distribution based technique provides a new analytical tool for food quality assessment.

Early recovery of isometric shoulder muscle strength after open acromioplasty in stage II impingement syndrome.

The recovery of shoulder muscle strength after open acromioplasty was evaluated in 48 patients (27 male, 21 female, mean age 44.3 years) who had undergone open acromioplasty because of stage II impingement syndrome. The isometric strengths of flexion, abduction and external rotation were measured before the operation and at 3, 6 and 12 months postoperatively. The mean preoperative flexion strength of the involved shoulder was 72.6% of that of the uninvolved shoulder, and this increased to 77.1% by 3 months post operation, to 88.3% at 6 and to 88.3% at 12 months. Corresponding abduction strengths were 68.4%, 80.4%, 88.7% and 91.0% and the external rotation strengths were 75.1%, 77.4%, 95.1% and 93.5%, respectively. These recoveries were markedly improved when the cases with poor subjective results at 1 year were not considered. The low preoperative strengths were more pronounced in women than in men, but recovery was better in women. It is concluded that shoulder muscle strengths recover to near normal in 1 year after open acromioplasty.

Longitudinal split of peroneus brevis tendon. A report on two cases.

BACKGROUND AND AIMS: To describe the clinical findings and surgical treatment of peroneus brevis split. MATERIAL AND METHODS: Two cases of longitudinal split of the peroneus brevis tendon are reported. One of the patients was a healthy middle-aged woman, who had fallen out of a car in a traffic accident and sprained her right ankle. Lateral ankle sprain was diagnosed and treated with a compression bandage. Lateral ankle pain persisted, however, with some swelling in the peroneal tendon region. MRI revealed a longitudinal partial rupture of the peroneus brevis tendon, which was treated surgically 12 months after the trauma. The second case was a 53-year-old woman, who had been suffering from rheumatoid arthritis for 2 years. Chronic pain and swelling in the peroneal tendon region were treated with 6 local corticosteroid injections without significant relief. Preoperative ultrasonography showed effusion of the peroneal tenosynovium, but the operation revealed a longitudinal split in the peroneus brevis tendon. RESULTS: In the first case, a single central peroneus brevis split was repaired with side-to-side suturation. After four weeks with a below-knee cast the patient was allowed to walk freely. At follow-up 12 months postoperatively, she was satisfied, although she still had some exertion pain in her ankle. In the second case, the torn fragment of the peroneus brevis tendon was excised and the ankle was mobilized early. Healing was complicated by a wound fistula, which was treated with antibiotics. Subluxation of the peroneus longus tendon necessitated a reoperation, which revealed a rerupture and a defect of the peroneus brevis tendon. The subluxation was repaired and the ruptured tendon ends were revised, followed by four weeks of below-knee cast immobilization, after which the patient was allowed to walk freely. The outcome was good. CONCLUSION: Peroneus brevis split easily goes unrecognised or misdiagnosed. It must be considered in patients with a history of single or recurrent ankle sprain or a chronic inflammatory disease. Lateral ankle pain, diffuse or local swelling in the peroneal tendon region, and a stable or instable ankle with no peroneal weakness are the main symptoms and findings. MRI is the most exact method for diagnosing tendon split. Surgical treatment usually gives good results.

Intramedullary nailing of humeral shaft fractures. A retrospective study of 126 cases.

Antegrade intramedullary nailing with four different implants was used in 126 humeral shaft fractures. There were 74 acute fractures, 17 pathologic fractures, 16 fractures malaligned in a hanging cast or brace, 15 fractures with delayed union and 4 fractures that were nailed after failed open reduction and internal fixation. The nonunion rate was 21/95 after primary operation, and after reoperations 14/95. Distraction of the fracture was a significant cause of nonunion, but not type of fracture, localization, implant, and delay between injury and surgery. Shoulder joint function was significantly impaired in 25/67 patients. The patients regarded the result as good or satisfactory in 41/67 of the cases who were followed mean 3 (0.5-10) years. We conclude that antegrade intramedullary nailing of humeral shaft fractures leads to a substantial risk of non-union and impairment of shoulder function. It can be recommended as primary treatment only when nonoperative treatment is likely to fail.

Open acromioplasty does not prevent the progression of an impingement syndrome to a tear. Nine-year follow-up of 96 cases.

We performed open acromioplasty for intractable impingement syndrome on 96 shoulders (93 patients) with an intact rotator cuff. All the shoulders were examined by ultrasound after a mean interval of nine years. Those showing pathological findings, a poor or fair subjective result, or deterioration of the primary excellent outcome had MRI and/or arthrography. The mean Constant score for the affected shoulders was 70 points and that for 48 non-involved, symptom-free shoulders, 84 points. The subjective outcome was excellent in 45, good in 24, fair in 18 and poor in 9 shoulders. Complete tears were found in 12 shoulders and partial tears in seven. A total of 14 shoulders was symptom-free after acromioplasty, but after an average of five years became painful again and showed deterioration. Of these, six had complete tears and four partial tears of the cuff. The tear rate was 4% in shoulders initially judged to be excellent, 25% in good, 33% in fair and 55% in poor shoulders. The tear rate was 71% in shoulders which subsequently deteriorated. The incidence was higher in men (25%) than in women (11%). We conclude that a tear of the rotator cuff may appear after acromioplasty, although there was no evidence of a tear at the time of operation. This is usually the reason for deterioration in a shoulder with an initially good operative outcome.

Dose-dependent suppression of the neutrophil respiratory burst by lidocaine.

BACKGROUND: Oxygen radical production is thought to be fundamental to the pathogenesis of post-ischaemic reperfusion injury which is routinely managed with lidocaine. Attention has, therefore, focused on the suppression of the neutrophil respiratory burst with a therapeutic endpoint. The widest application of lidocaine remains in local analgesia. METHODS: A standard chemiluminescence technique was used to assess the human neutrophil leukocyte response to increasing doses of lidocaine in the presence or absence of particulate hydroxyapatite. RESULTS: No reduction of oxygen radical production was seen at the drug concentration of 1 mg/ml. A clear, concentration-dependent inhibition was seen at 2 mg/ml, 3 mg/ml, 4 mg/ml and 8 mg/ml concentrations. These drug concentrations may be reached at or near the site of injection in local anaesthetic use. CONCLUSION: Lidocaine showed profound anti-inflammatory action in this experimental system. Controlled studies in the clinical setting would identify the optimal analgesic and anti-inflammatory dosage, whilst preserving host defence without compromising tissue repair.

Pathological fractures of the humeral shaft.

BACKGROUND AND AIMS: To evaluate the results, complications and survival after intramedullary (IM) nailing of pathological humeral shaft fractures associated with metastatic disease. MATERIAL AND METHODS: Sixteen patients (mean age 64 years) with 18 pathological fractures of the humeral shaft were treated by IM nailing in Oulu University Hospital from 1987 to 1997. Retrospective evaluation of charts and radiographs was carried out. Breast carcinoma and multiple myeloma were the most common diagnoses. The mean interval from diagnosis of malignancy to fracture was 47 (1-168) months. RESULTS: Mean duration of the operation was 62 (25-95) minutes and mean intraoperative blood loss was 200 (50-600) ml. Complications were rare. Survival after the fracture averaged 160 (39-511) days. Two patients (3 fractures) were alive at the time of the evaluation, with satisfactory or good pain relief. CONCLUSIONS: Pathological fracture of the humeral shaft occurs late in the course of malignant disease. IM nailing is a safe, rapid and effective procedure for treating pathological fractures of the humeral shaft.