Long-term outcome after revision of hip arthroplasty with the BioBall® adapter system in multimorbid patients.

INTRODUCTION: Long-term study evidence about the BioBall® adapter system is limited, especially in highly morbid elderly patients. Thus, we analysed the long-term outcome of revision hip arthroplasty using this system in highly morbid elderly patients. MATERIALS AND METHODS: We included 19 patients undergoing revision hip arthroplasty after primary or secondary total hip arthroplasty dislocations between July 2002 and August 2004 and followed up their long-term outcome until 2015. RESULTS: The patients achieved a median of 17 points in the Merle d'Aubigné hip score in 2004 and a median of 18 points in 2011, and the 4 surviving patients in 2015 achieved 18 points. For the four 12-year survivors, the Merle d'Aubigné score was virtually stable over the complete observation period. The Harris Hip Score showed comparable results. The patients had a median Barthel index of 90 in 2004 and 100 in 2011, and the 4 survivors in 2015 had Barthel indices of 65, 95, 100, and 100, respectively, in 2015. CONCLUSIONS: In multimorbid patients, using the BioBall® adapter system for total hip arthroplasty, revision due to dislocation results in good long-term outcome without impairment of quality of life. TRANSLATIONAL POTENTIAL: Our study provides long-term evidence in a vulnerable patient population. It shows how the therapeutic concept of revision hip replacement with an adapter device translates into long-term outcome and quality of life in these patients. Thus, it adds important information for evaluation of therapeutic options in this field.

Activity of the antiseptic polyhexanide against gram-negative bacteria.

The activity of the antiseptic polyhexanide was tested against 250 gram-negative clinical isolates, that is, 50 isolates each of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Moraxella catarrhalis, and Haemophilus influenzae. Minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) were determined by using a serial broth microdilution technique according to DIN 58940. Time-kill studies were performed for reference stains E. coli ATCC 25922, K. pneumoniae ATCC 4352, P. aeruginosa ATCC 15442, M. catarrhalis ATCC 43617, and H. influenzae ATCC 49247. All tested isolates had MICs and MBCs within a range of 1-32 mg/L and were regarded as susceptible to polyhexanide. The highest values were found for P. aeruginosa and H. influenzae with MICs and MBCs of 32 mg/L. Addition of up to 4% albumin to the test medium did not change MICs and MBCs. Time-kill studies of the reference strains showed reduction rates from 3 log10 colony forming units (CFU)/ml to more than 5 log10 CFU/ml for 200 and 400 mg/L polyhexanide within 5-30 min. Testing of polyhexanide in combination with antibiotics showed indifference with amoxicillin, cefotaxime, imipenem, gentamicin, and ciprofloxacin; no antagonism was found. As no resistance and no antagonism with antibiotics were detected, polyhexanide is regarded as suitable agent for topical eradication of gram-negative bacteria.

In-vitro analysis of the effect of gentamicin and polyhexanide on bone tissue.

PURPOSE: Though anti-infectives have been used for a long time in surgical procedures, the effect on bone tissue has not been determined for most antibiotics and antiseptics. METHODS: In our in vitro study, 4x4x8 mm(3) blocks of rabbit cancellous bone tissue were incubated with Ringer's solution, gentamicin and Lavasorb(®) each for time intervals of 15 minutes, 30 minutes, one hour, four hours and eight hours. Samples were examined double blinded through optical and electron microscopy. RESULTS: Tissue degeneration was observed in all samples. It was low in Ringer's solution. Samples with Lavasorb showed a moderate degeneration after 15 and 30 minutes, which was accelerated after one hour. Gentamicin led to a moderate degeneration of bone tissue after 15 and 30 minutes and to a more accelerated degeneration after one hour. The effect of gentamicin on bone tissue was more pronounced than the effect of Lavasorb. CONCLUSIONS: This investigation showed that local application of Lavasorb or gentamicin on bone tissue should be restricted to 30 minutes, while Lavasorb showed a better tissue tolerability. This finding could have clinical implications for the management of wounds with open osseous tissue and should be further investigated by in vivo studies.

1150 kyphoplasties over 7 years: indications, techniques, and intraoperative complications.

In our cohort of 555 patients with a total of 1150 vertebral fractures treated with kyphoplasty we performed a 30-day postoperative analysis of cement leakage, neurological symptoms, pulmonary embolism, and infections. In our department, 22% of kyphoplasties were performed with calcium phosphate cement and the remainder with polymethylmethacrylate. All patients were initially assessed by an interdisciplinary kyphoplasty colloquium, composed of consultants in traumatology, radiology, and endocrinology. Indications included fresh traumatic vertebral fractures; painful sintered osteoporotic vertebrae; osteolysis and painful vertebral body collapse caused by multiple myelomas; and lymphomas and pathological fractures due to metastases of malignant tumors (prostate cancer, breast cancer, ovarian cancer, and malignant melanoma) or benign vertebral tumors (hemangioma). Contraindications included patients with instability of the posterior wall and/or pedicles, an infection of the fractured vertebra, a severe hemorrhagic diathesis, known allergies to the cements, pregnancy, and ASA score of 4. The standard postoperative computed tomography scan of the kyphoplasty-treated vertebrae revealed a dorsal cement leakage in 38 vertebrae representing 3.3% of all levels. A permanent monoparesis of the left leg, 2 cases of temporary neurological deficits, 2 cases of hemorrhage, and 1 asymptomatic pulmonary embolism were observed as postoperative complications. We observed no complications relating to polymethylmethacrylate described in the literature. By careful interdisciplinary indication setting and a standardized treatment model, kyphoplasty presents a safe and effective procedure for the treatment of various vertebral fractures.

Cbfa-1 (Runx-2) and osteocalcin expression by human osteoblasts in heparin osteoporosis in vitro.

Heparin may cause adverse effects on bone formation following long-term application. The exact pathomechanism is unclear, but in vitro data suggest an impaired osteoblast function. The transcription axis of Cbfa-1 (Runx-2) and osteocalcin is crucial in maintaining an equilibrium of bone formation and resorption in vivo. We used a human osteoblast cell culture model to further investigate the effect of heparin (low-molecular-weight heparin, dalteparin) on the expression of these two regulators of osteoblast differentiation. At high doses, dalteparin caused a significant inhibition of both osteocalcin and Cbfa-1 expression in vitro. Our data support the hypothesis of a direct inhibition of osteoblast function underlying heparin osteoporosis.

The use of nanocrystalline hydroxyapatite for the reconstruction of calcaneal fractures: Preliminary results.

The purpose of this investigation was to evaluate the feasibility of a nanocrystalline hydroxyapatite compound in the treatment of calcaneal fractures with osseous defects after reduction. The study included 21 patients, representing 24 closed intraarticular calcaneus fractures with large defects remaining after operative reduction. All cases were supplemented with the hydroxyapatite bone substitute and stabilized with a calcaneal honeycomb plate. Radiographs were taken at 6 weeks, 12 weeks, 6 months, and 1 year postoperatively, with specific attention given to measurement of Gissane's angle, Böhler's angle, and calcaneal height. A postoperative subjective and objective evaluation of the fracture, using the Creighton Nebraska Health Foundation scale, was performed 1 year postoperatively. Böhler's angle improved from a mean 8.6 +/- 5.3 degrees preoperatively to an immediate postoperative mean result of 31.5 +/- 6.5 degrees and 27.7 +/- 8.6 1 year postoperatively. The mean Creighton-Nebraska functional score was 86 +/- 10 at the 1-year follow-up evaluation. These results suggest that open reduction with plate fixation combined with nanocrystalline hydroxyapatite augmentation presents a good and reliable surgical technique for treatment of calcaneus fractures.

Bacterial decontamination of surgical wounds treated with Lavasept.

In a prospective randomized controlled double-blind study in 50 acutely injured patients, bacterially contaminated type 2-4 soft tissue wounds were treated with moist dressings of 0.2% Lavasept (fractionated polyhexamethylenbiguanide and macrogolum 4000) solution (n=28) in comparison with Ringer solution (n=22). Standardized swabs were taken on days 0, 2, 8 and 15 and investigated for microorganisms. For a quantitative evaluation, the number of colony forming units (CFU) was determined by a serial dilution technique. The tissue compatibility and anti-inflammatory effect were rated on a scale of 0 (=bad) to 3 (=very good). The most frequently found microorganism was Staphylococcus aureus, which was isolated from 13 wounds. Use of Lavasept led to a faster and significant reduction in microorganisms on the wound surfaces. The number of CFU per wound remained constant or decreased, in contrast to the wounds treated with Ringer solution. This was true for both Gram-positive and Gram-negative bacteria. There was no evidence of impaired wound healing in either group. The anti-inflammatory effect and the tissue compatibility of Lavasept were rated significantly better than that of Ringer solution. It is concluded that Lavasept combines antiseptic action with good tissue compatibility.

Void filling of tibia compression fracture zones using a novel resorbable nanocrystalline hydroxyapatite paste in combination with a hydroxyapatite ceramic core: first clinical results.

INTRODUCTION: It is a generally accepted standard surgical practice to fill-in the metaphyseal defect zones resulting from the reduction of tibia compression fractures. The development of various innovative bone substitutes is also currently on the increase. MATERIALS AND METHODS: In our prospective study, we used Ostim, a novel resorbable nanocrystalline hydroxyapatite paste, together with Cerabone, a solid hydroxyapatite ceramic, in combination with angularly stable osteosynthesis to treat 24 tibia compression fractures. Types B2 and B3, as well as types C2 and C3 fractures, according to the AO classification, were included in the study. RESULTS: The mean total range of joint motion in terms of flexion and extension was improved from the immediate postoperative value of 79 +/- 14 degrees to 97 +/- 13 degrees at 6 weeks after surgery, to 109 +/- 16 degrees at 3 months, and finally to 118 +/- 17 degrees at 1 year. In three patients, a delayed wound healing was observed as a local complication. CONCLUSION: The use of the Ostim and Cerabone combination is an effective method in treating tibia compression fractures with large defect zones left after reduction.

Surgical treatment of fractures of the distal radius with plates: a comparison of palmar and dorsal plate position.

INTRODUCTION: While most fractures of the distal radius can be treated successfully by conservative means, some fractures-especially the more complicated fracture types-require surgical fixation. One of the operative techniques is plate osteosynthesis, which can be performed in either a dorsal or a palmar plate position. MATERIALS AND METHODS: This study reports on 122 fractures of the distal radius treated by open reduction and internal fixation with the T-plate, investigating the long-term outcome after an average period of 42.4 months. The follow-up examination contained a subjective, a clinical and a radiological part, and the results were evaluated according to the scores of Stewart and of Castaing with special emphasis on the question of whether palmar or dorsal plating showed any differences in outcome, and if so, what they were. RESULTS: The radiological results (Stewart 1 score; i.e. the anatomical reduction) were "excellent" or "good" in 87.7% of cases. There were significant differences with respect to age, gender and plate position: patients older than 80 years and women had significantly worse results, and dorsal plating was significantly better than palmar plating. The functional outcome (Stewart 2 score) was"excellent" and 'good' in 90.2% of cases. These functional results showed a tendency for dorsal plating to be better, but the differences were not significant. There was a close correlation between the radiological and the clinical findings. With the Castaing score, which combines both functional and radiological outcomes, there were 73.8% perfect and good results. CONCLUSION: This study shows that the majority of patients with problem fractures of the distal radius can be successfully treated by internal fixation using the T-plate. The dorsal approach to the distal radius--in cases where dorsal plating is appropriate--will result in a better anatomical reduction and clinical outcome.