[Geriatric Proximal Femoral Fracture and Urinary Tract Infection - Considerations for Perioperative Infection Prophylaxis]. / Geriatrische proximale Femurfraktur und Harnwegsinfekt ­ Überlegungen zur perioperativen Infektionsprophylaxe.

Background: Perioperative infection prophylaxis with cephalosporins is standard in surgical treatment of proximal femoral fractures (PFF). Geriatric patients (pat.) are at risk of chronic infections and the bacteria from these can lead to unknown hygienic problems in an early operation. We therefore characterised the colonisation of the urinary tract in pat. (≥ 65 years) with PFF and observed bacterial development in deep wound infections over a period of 10 years. The aim was to discover gaps in perioperative infection prophylaxis. Patients and Methods: Between September 2013 and November 2015, colonisation of the urinary tract and microbial resistance were investigated on admission of all pat. (≥ 65 years) with the diagnosis of PFF (n = 351; f/m 263/88; median age [∅] 83.57 [65-100] years). Between 2005 and 2014, 2161 pat. with a PFF were operated in our clinic (f/m 1623/538; ∅ 82.35 [65-101] years). 991 pat. (∅ 81.84 [65-101] years) with femoral neck fracture [FNF] were treated with endoprosthesis/osteosynthesis, 1170 pat. (∅ 82,78 [65-101] years) with per-/subtrochanteric fracture [PTF] were treated with osteosynthesis. In a retrospective data analysis, deep wound infections, microbiological composition and changes in microbial resistances over time were identified. Results: Bacteriuria (BU) was detected in the urine sediment of 35.61 % (n = 125) of our pat. In 47.2 % of these pat., BU was accompanied by laboratory signs of manifest urinary tract infection. In 10.4 % of these pat., colonisation of the urinary tract with multi-resistant pathogens was detected; 26.4 % were resistant to cefuroxime. The rate of deep infections in pat. with endoprosthesis/osteosynthesis in FNF was 2.8 % (n = 28; f/m 19/9; ∅ 81.35 [67-92] years), with osteosynthesis in PTF 1,1 % (n = 14; f/m 10/4; ∅ 81.0 [70-91] years). A comparison of the periods 2005-2009 and 2010-2014 showed a shift in the spectrum of pathogens from cephalosporin-sensitive to cephalosporin-resistant enterococci. Resistance of pathogens against cephalosporins increased from 43 to 81 %. Conclusion: We found an increasing risk in geriatric pat. from multiresistant pathogens in the urinary tract and from an increase in the cephalosporin resistance of pathogens in urinary tract infections and in deep wound infections. This indicates that perioperative infection prophylaxis with a cephalosporin is not effective. Especially in nursing homes, development of resistance to antibiotics is an increasing problem. Thus, concepts of perioperative infection prophylaxis in geriatric patients should be reconsidered.

[Intramedullary Stabilisation of Displaced Midshaft Clavicular Fractures in Heavy Workers and Complex Fracture Pattern]. / Intramedulläre Stabilisation von dislozierten Klavikulaschaftfrakturen bei Schwerarbeitern und komplexen Frakturen.

BACKGROUND: The medical literature recommends plate osteosynthesis (PO) for complex displaced midshaft clavicular fractures (DMCF) OTA type 15B3 and for heavy workers with displaced clavicular fractures. Recovery of DMCF treated with intramedullary stabilisation (IMS) will be examined and compared to published data for duration of inability to work (DIW) after conservative treatment as well as after PO, with respect to the DIW. PATIENTS AND METHODS: Between 09/2009 and 07/2015, the DIW of 58 patients (8 f, 50 m, mean age 38.4 [20-59] years) with DMCF treated with open reduction and IMS (Titanium Elastic Nail [TEN], Synthes, Umkirch, Germany) was determined. Inclusion criteria were the presence of closed unilateral DMCF and presence of a job with national insurance at the time of accident. DIW was counted in days, starting with the accident, and ending on the last day before resumption of full work. All patients were functionally treated for 6 weeks postoperatively without weights for the shoulder and with a maximum of 90° abduction/flexion. The workload was classified in accordance with REFA criteria: group 0-1 (low physical workload) and group 2-4 (high physical workload). Fracture patterns (simple vs. complex) and postoperative physiotherapy (yes vs. no) were investigated for both REFA groups, as these factors may influence DIW. Fracture classification was performed in accordance with the OTA classification, as simple fractures (OTA type 15B1 and 15B2), and complex fractures (OTA type 15B3). Effects were concerned significant if p ≤ 0.05. RESULTS: Median DIW was independent of physical workload, with 39.86 (3-150) days (n = 58). Patients with low physical workload (REFA 0-1; n = 33) had shorter duration of DIW, with an average of 32.48 (3-136) days than patients with higher physical workload (REFA 2-4; n = 25), with 49.6 (14-150) days (p = 0.02). The fracture type did not influence this significantly (simple fractures [n = 35]: average 40.54 [3-150] days; complex fractures [n = 23]: average 38.82 [14-136] days, p = 0.85). Within each REFA group, differences in DIW for each fracture type were greater, but did not attain statistical significance. Patients without postoperative PT (n = 30) had a shorter DIW, with an average of 30.5 (3-84) days, than patients with postoperative PT (n = 28), with an average of 49.89 (14-150) days (p = 0.021). Within both REFA groups, DIW changed similarly with postoperative PT, in some cases with statistical significance. CONCLUSION: DIW after IMS of DMCF does not depend on the complexity of the fracture. For heavy workers, DIW after IMS is significantly longer than for light physical workers. IMS of DMCF permits immediate pain-adapted movement of the shoulder, with a maximal abduction/flexion up to 90°, no matter what the fracture type. Patients given additional professional PT showed longer DIW than those without such treatment.

[A Problematic Case: Removal of a Broken Cannulated Tibial Nail]. / Problemfall: Entfernung eines gebrochenen kanülierten Tibiamarknagels.

We present a case illustrating a simple and safe technique for the removal of a broken cannulated tibial nail after a pseudarthrosis of a lower leg shaft fracture. A 3 mm Ball-Tip guide wire was inserted into the proximal and the distal segment of the nail. A 2.5 mm tip-flattened second wire was forwarded into the distal segment pushing the Ball-Tip guide wire out of the axis and blocking it. This way the Ball-Tip could act as a hook and consecutively could be knocked back with an impactor forceps removing the complete nail. An exchange nailing was performed with a reamed AO standard nail and the further course was uneventful with a healed fracture after 12 months.

[Intramedullary stabilisation of displaced midshaft clavicular fractures: does the fracture pattern (simple vs. complex) influence the anatomic and functional result]. / Intramedulläre Stabilisation von dislozierten Klavikulaschaftfrakturen - Hat die Frakturform (einfach vs. komplex) Einfluss auf das anatomische und funktionelle Ergebnis?

BACKGROUND: Displaced midshaft clavicular fractures are often treated operatively. The most common way of treatment is plating. Elastic stable intramedullary nailing (ESIN) is an alternative, but seldom used. Studies showed comparable or even better results for intramedullary nailing than for plating in simple 2- or 3-fragment midshaft fractures. The indication of ESIN for multifragmentary clavicular fractures is discussed critically in the literature because of reduced primary stability and danger of secondary shortening. Until now only few studies report functional results after fracture healing depending on the fracture type. To the best of our knowledge there is no study showing significantly worse functional scores for ESIN in complex displaced midshaft fractures. The objective of this study was to examine anatomic and functional results of simple (2 or 3 fragments, OTA type 15B1 and 15B2) and complex (multifragmentary, OTA type 15B3) displaced midshaft clavicula fractures after internal fixation. PATIENTS AND METHODS: Between 2009 and 2012, 40 patients (female/male 10/30; mean age 33 [16-60] years) with closed displaced midshaft clavicular fractures were treated by open reduction and ESIN (Titanium Elastic Nail [TEN], Synthes, Umkirch, Germany). Thirty-seven patients were retrospectively analysed after a mean of 27 (12-43) months. Twenty patients (group A) had simple fractures (OTA type 15B1 and 15B2), 17 patients (group B) had complex fractures (OTA type 15B3). All shoulder joints were postoperatively treated functionally for six weeks without weight limited to 90° abduction/flexion. Both groups were comparable in gender, age, body mass index, months until metal removal, number of physiotherapy sessions and time until follow-up examination. Joint function (neutral zero method) and strength (standing patient with arm in 90° abduction, holding 1-12 kg for 5 sec) in both shoulders were documented. The distance between the centre of the jugulum and the lateral acromial border was measured for both sides. The DASH, Constant-Murley, Oxford shoulder and clavicular scores (Jubel) were calculated. Patients documented contentedness of outcome by VAS between 0 (absolute discontented) and 10 (very contented). Complications were recorded. RESULTS: Operatively treated displaced midshaft clavicular fractures. in comparison to the healthy side in group A had an average shortening of 5 (0-20) mm and in group B of 10 (3-25) mm, with a statistical significance between both groups. Patients of both groups were very contented with the results (VAS group A: 9.6; B: 9.5). DASH score (group A: 28; B: 3.1), Constant-Murley score (group A: 95.0; B: 93.8), Oxford shoulder score (group A: 46.2; B: 45.9) and the clavicula score (Jubel) (group A: 1.2; B: 2.1) were comparable between both groups without significance. In 4 patients (11%) complications occurred. Once (group B) an infection was seen, three times (group B) the ESIN had to be shortened on the medial side because of telescoping. CONCLUSION: Open ESIN of simple and complex displaced midshaft clavicular fractures leads after an average of 27 months to good or even excellent results. Healing of the clavicle in a modestly shortened position does not impair the patient.

Refixation of osteochondral fractures by ultrasound-activated, resorbable pins: An ovine in vivo study.

OBJECTIVES: Osteochondral injuries, if not treated adequately, often lead to severe osteoarthritis. Possible treatment options include refixation of the fragment or replacement therapies such as Pridie drilling, microfracture or osteochondral grafts, all of which have certain disadvantages. Only refixation of the fragment can produce a smooth and resilient joint surface. The aim of this study was the evaluation of an ultrasound-activated bioresorbable pin for the refixation of osteochondral fragments under physiological conditions. METHODS: In 16 Merino sheep, specific osteochondral fragments of the medial femoral condyle were produced and refixed with one of conventional bioresorbable pins, titanium screws or ultrasound-activated pins. Macro- and microscopic scoring was undertaken after three months. RESULTS: The healing ratio with ultrasound-activated pins was higher than with conventional pins. No negative heat effect on cartilage has been shown. CONCLUSION: As the material is bioresorbable, no further surgery is required to remove the implant. MRI imaging is not compromised, as it is with implanted screws. The use of bioresorbable pins using ultrasound is a promising technology for the refixation of osteochondral fractures.

Biomechanics of femoral interlocking nails.

Today there is a variety of different interlocking intramedullary nail designs available for the femur. We compared different nail types in the bone implant complex (BIC) of four unreamed solid nails and a slotted reamed nail with simulated comminuted mid shaft fractures to see if there are major differences in stiffness for axial load, bending and torsion. The fractures were simulated by a 2 cm defect osteotomy in paired human cadaver femora. Each bone was tested intact in a universal testing machine, osteotomy and osteosynthesis were performed, and the BIC was tested. Relative stiffness was calculated. In torque testing the unslotted solid nail showed significantly more stiffness (0.6-1.8 Nm/degrees) compared to the slotted nail (0.2 Nm/degrees). Compared to intact bone (6.9 Nm/degrees), both groups of nails were significantly less stiff (relative stiffness 2-20%). In axial load and bending testing the large diameter unreamed nail showed significantly higher stiffness (32-68%). This study shows that stiffness of bone implant complex in interlocking femoral nails is more dependent on nail profile than on the pressfit of nails in the medullary canal.

[Pre-bending and and tension adjustment of narrow 4.5 mm AO titanium LC-DCP (limited contact dynamic compression plate)]. / Vorbiegung und Vorspannung bei der schmalen 4,5-mm-AO-Titan-LC-DCP.

UNLABELLED: To assess the behavior of the LC-DCP with prebending and pretensioning we tested: gap angle vs. tensioning force without prebending; Bending moment for different prebending angles; In a model using a fiber tube to simulate the bone for different prebending angles and pretensioning forces of the LC-DCP the deformation in 4 point bending open was tested. Maximum prebending angle was 24 degrees, maximum pretensioning force was 2400 N; in human cadaver tibiae angles of 3 degrees, 9 degrees, 24 degrees and forces of 300 N, 1000 N and 1500 N, were tested to look for the difference in a less idealized model. RESULTS: 1. A near linear curve for gap angle vs. force with an angle of 0.45 degree/100 N was found between 100 N and 1500 N; 2. We did not find a near linear bending moment/bending angle curve up to 8 degrees like in the DCP but an exponential curve development as it had to be expected by the lower modulus of elasticity of titanium; 3. the maximum mechanical stability was found for a angle of 24 degrees and a force of 1500 N. The titanium LC-DCP shows a different mechanical reaction to prebending and pretensioning in the bone implant complex compared to stul DCP. Optimum prebending and pretensioning for axial compression and mechanical stability in the LC-DCP are by far greater than clinically possible. From our mechanical testing a prebending angle of 24 degrees and a pretensioning force of 1500 N would allow the largest axial compression and show the most resistance against deformation in bending open. In the clinical setting this would result in difficult reduction and therefore, we recommend a prebending angle of 9 degrees and a pretensioning force of 1000 N.