Screw-in-screw fixation of fragility sacrum fractures provides high stability without loosening-biomechanical evaluation of a new concept.

Surgical treatment of fragility sacrum fractures with percutaneous sacroiliac (SI) screw fixation is associated with high failure rates. Turn-out is detected in up to 20% of the patients. The aim of this study was to evaluate a new screw-in-screw implant prototype for fragility sacrum fracture fixation. Twenty-seven artificial hemipelvises were assigned to three groups (n = 9) for instrumentation of an SI screw, the new screw-in-screw implant prototype, ora transsacral screw. Before implantation, a vertical osteotomy was set in zone 1 after Denis. All specimens were biomechanically tested to failure in upright position. Validated setup and test protocol were used for complex axial and torsional loading applied through the S1 vertebral body to promote turn-out of the implants. Interfragmentary movements were captured via optical motion tracking. Screw motions were evaluated by means of triggered anteroposterior X-rays. Interfragmentary movements and implant motions were significantly higher for SI screw fixation compared to both transsacral and screw-in-screw fixations. In addition, transsacral screw and screw-in-screw fixations revealed similar construct stability. Moreover, screw-in-screw fixation successfully prevented turn-out of the implant that remained during testing at 0° rotation for all specimens. From biomechanical perspective, fragility sacrum fracture fixation with the new screw-in-screw implant prototype provides higher stability than an SI screw, being able to successfully prevent turn-out. Moreover, it combines the higher stability of transsacral screw fixation with the less risky operational procedure of SI screw fixation and can be considered as their alternative treatment option.

An excellent 5-year survival rate despite a high incidence of distal femoral cortical hypertrophy in a short hip stem.

BACKGROUND: Although reported results on short stems sound very promising, the occurrence of distal femoral cortical hypertrophy is often observed. The aim of the present study was to report 5-year survival data of a commercially available trochanter sparing short stem and investigate the clinical impact of distal femoral cortical hypertrophy on the outcome. METHODS: 123 total hip arthroplasties were performed on 120 patients from April 2008 to May 2010 (mean age 62, range 29-89 years; 71 hips from male patients, 58%). Clinical and radiological data were collected preoperative, at 6 weeks, 1, 2, 3, and 5 years postoperative to assess the outcome. Radiographs taken immediately postoperative as well as 1 and 5 years postoperative were used to identify and assess cortical hypertrophy. RESULTS: 1 stem had to be revised due to aseptic loosening, resulting in a Kaplan-Meier survival analysis with endpoint for stem revision of 99.2% (95% Confidence Interval 94.1-99.9) at 5 years. 96 radiological and 95 clinical follow-ups were analysed 5 years postoperative. 68 (71%) hips showed distal femoral cortical hypertrophy after 5 years. The average Harris Hip Score and Oxford Hip Score improved 33 (standard deviation (SD) 15.1, range 2-70), 18 (SD 12.1, range -10-43) points, respectively. Overall 16% of the patients reported thigh pain, unrelated to the presence of cortical hypertrophy. DISCUSSION: This short stem shows an excellent 5-year survival rate and good clinical outcome despite a high incidence of cortical hypertrophy. However, the question of the mechanism of load transfer arises.

Is suture comparable to wire for cerclage fixation? A biomechanical analysis.

BACKGROUND: Cerclage wire is the current standard for circumferential bone fixation. Advances in technology have improved modern sutures, allowing for expanded utility and broader application. The present study compared the strength and durability of cerclage fixation between modern suture materials and monofilament wire. METHODS: The Surgeon's Knot, the Nice Knot and the Modified Nice Knot, were each tied using three separate suture materials: no. 2 FiberWire (Arthrex, Naples, FL, USA), no. 2 Ultrabraid (Smith & Nephew, Andover, MA, USA) and no. 5 Ethibond (Johnson & Johnson, Somerville, NJ, USA). These sutures were compared with monofilament wire. Sutures were secured around a fixed diameter using three additional half hitches, whereas a 1.2-mm (18 gauge) stainless steel monofilament wire was used for comparison. One fellow and one orthopaedic surgery resident each tied five trials with every knot/material combination. Samples were subjected to cyclic loading and quasi-static load testing. Respectively, cyclic displacement over time and load to failure were analyzed. Clinical failure (3 mm of cyclic displacement) and absolute failure (opening of the knot or material failure) were the outcomes of interest. RESULTS: During cyclic loading, Ethibond displaced significantly less over time compared to monofilament wire (p < 0.003), whereas FiberWire showed no significant difference. Ultrabraid also behaved similar to wire, except displacing significantly more than wire only with the Surgeon's Knot (p = 0.02). During load to failure, Ethibond and FiberWire failed at significantly greater loads than monofilament wire (p < 0.001), whereas Ultrabraid performed similar to wire. Knot types did not appear to impact the results. CONCLUSIONS: High-performance sutures achieve superior results in biomechanical testing under cyclic and quasi-static load compared to monofilament wire, suggesting that they provide an alternative to wire for cerclage fixation with select clinical application. Biomechanical security of suture cerclage is dependent on suture material, although it is not altered significantly by choice of knot. An ex-vivo study with clinical application would further reinforce whether suture cerclage offers a valid alternative to wire cerclage.

Decrease surgery time by using an alternative lateral parapatellar approach for tibia shaft fracture nailing.

INTRODUCTION: Medial parapatellar or transpatellar ligament approaches are commonly used for nail osteosynthesis in tibia shaft fractures. The lower leg is normally in a hanging position to allow guide wire insertion and reaming of the tibia. However, this position complicates fracture reduction and retention, as well as image intensification throughout the procedure. A lateral parapatellar approach with the lower leg in a semi-extended, horizontal position has been previously described for proximal tibial fracture fixation. The purpose of the presented study was to share the lateral parapatellar approach technique used in our institution and to analyse its feasibility for tibia shaft fracture fixation when compared to a medial parapatellar and transpatellar incision technique. MATERIALS AND METHODS: All patients with tibial shaft fractures treated at our institution between 2009 and 2012 by intramedullary nailing through either a transpatellar, a medial parapatellar or a lateral parapatellar approach were reviewed. Demographics, injury pattern and the operative procedure, especially operation and fluoroscopy time, were analysed. RESULTS: 73 patients were enrolled into the study. Twenty-six patients were treated by use of a lateral parapatellar approach, whilst a transpatellar or a medial parapatellar approach was chosen in 29 and 18 cases, respectively. Patients' characteristics were similar regarding gender and body mass index. When compared to the transpatellar (126 ± 30 min) or the medial parapatellar approach (105 ± 29 min), surgical time was significantly shorter in the lateral parapatellar approach group (96 ± 29 min). Likewise, shorter image intensifier time was documented when a lateral parapatellar approach was chosen (211 ± 189 s) compared to the transpatellar (347 ± 204 s) or the medial parapatellar approach (241 ± 222 s). CONCLUSION: The extra-articular semi-extended tibial nailing technique using a lateral parapatellar approach was associated with a significant decrease in time of surgery, while fluoroscopy time was shorter but not significantly different between the three groups.

Clinical application of a minimally invasive cement-augmentable Schanz screw rod system to treat pelvic ring fractures.

PURPOSE: The purpose of this study is to analyze the results using the USS fracture MIS system (DePuy Synthes) to treat instable pelvic ring fractures. As its outstanding feature, it is the only Schanz screw and rod system at present that combines angular stability, perforation/fenestration of the screws for cement-augmentation, a variable screw length, and a large screw diameter. MATERIALS AND METHODS: Retrospective investigation of 134 pelvic ring fractures treated in 2012-2013. Twenty-five patients obtained the abovementioned implant. Besides baseline characteristics of the included patients and the surgical procedure, a clinical/radiological follow-up of six months was analyzed. RESULTS: Dividing the collective into two groups, I high-energy trauma and II fragility fracture of the pelvis, the following results were recorded: group I: ten patients, six male, age 48.4 ± 19.7 years. Mean ISS 41 ± 22.5, fracture classification: AO/OTA type 61 B1/C1/C3 = 1/5/4. Operative treatment: three transiliac internal fixator, seven iliolumbar fixation, one implant was cement-augmented. Group II: 15 patients, 14 female, age 77.5 ± 10.1 years. Fracture classification according to Rommens: FFPII/III/IV = 6/1/8. Operative treatment: eight transiliac internal fixator, seven iliolumbar fixation, 14 implants were cement-augmented. Overall surgical side complications: 16%. Radiological examination: correct positioning of all ilium screws. Follow-up after six month (16 patients): all showed fracture consolidation. One ilium screw was broken close to the connecting clamp. CONCLUSION: The investigated Schanz screw rod system is a suitable implant to broaden the established procedures to stabilize dorsal pelvic ring fractures. TRIAL REGISTRATION: The study is registered at the Clinical Trial Registry University of Regensburg (Number Z-2017-0878-3).

Benefits of hardware removal after plating.

Routine implant removal is frequently performed although evidence-based guidelines are lacking. But routinely planned implant removal has significant economic implications and shows considerable complication rates. In general, clinical outcome seems to improve but pain relief after operation is often unpredictable. Even in patients reporting implant-related pain, implant removal does not guarantee relief and may be associated with further complications. The intra- and postoperative complication rate remains very high. Implant removal demonstrates a significant learning curve and unsupervised junior surgeons tend to cause more complications. The need for implant removal may be questioned. Even with the implant in place, contact activities can be resumed. However, a new adequate trauma can create a new fracture independently if there is an implant in-situ or not. It is important to understand the complications and outcomes to be expected with hardware removal to carefully evaluate its indication.

Biomechanical investigation of four different fixation techniques in sacrum Denis type II fracture with low bone mineral density.

With increasing life expectancy, fragility fractures of the pelvic ring are seen more frequently. Although their osteosynthesis can be very challenging, specific biomechanical studies for investigation of the fixation stability are still lacking. The aim of this study was to biomechanically evaluate four different fixation methods for sacrum Denis type II fractures in osteoporotic bone. Unstable Denis type II vertical sacrum fractures were created in 16 human pelves. Their osteosynthesis was performed with one sacro-iliac screw, posterior sacral plating, triangular fixation, or spino-pelvic fixation. For that purpose, each pelvis was randomly assigned to two paired groups for treatment with either SI-screw/posterior sacral plating or triangular fixation/spino-pelvic fixation. Each hemi-pelvis was cyclically tested under progressively increasing axial compression. Relative interfragmentary movements were investigated via optical motion tracking analysis. Axial stiffness of triangular fixation was significantly higher versus posterior sacral plating and spino-pelvic fixation (p ≤ 0.022), but not significantly different in comparison to SI-screw fixation (p = 0.337). Cycles to 2, 3, 5, and 8 mm fracture displacement, as well as to 3°, 5°, and 8° gap angle at the fracture site were significantly higher for triangular fixation compared to all other groups (p ≤ 0.041). Main failure mode for all osteosynthesis techniques was screw cutting through the bone, leading loss of fixation stability. From a biomechanical point of view, triangular fixation in sacrum Denis type II fractures demonstrated less interfragmentary movements and should be considered in unstable fragility fractures of the sacrum. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1624-1629, 2018.

Knee joint kinematics with dynamic augmentation of primary anterior cruciate ligament repair - a biomechanical study.

BACKGROUND: Dynamic augmentation of anterior cruciate ligament tears seems to reduce anteroposterior knee translation close to the pre-injury level. The aim of the present study is to biomechanically investigate the course of translation during a simulated early post-operative phase. It is hypothesized that anteroposterior translation is maintained at the immediate post-operative level over a simulated rehabilitation period of 50'000 gait cycles. METHODS: Eight fresh-frozen human cadaveric knee joints from donors with a mean age of 35.5 (range 25-40) years were subjected to 50'000 cycles of 0°-70°-0° flexion-extension movements in a custom-made test setup. Anteroposterior translation was assessed with simulated Lachman/KT-1000 testing in 0°, 15°, 30°, 60° and 90° of flexion in knee joints treated with the novel technique initially and after 50'000 cycles testing. Statistical analysis was performed using the Wilcoxon Signed-Rank Test. The level of significance was set at p = 0.05. RESULTS: Anteroposterior translation changed non-significantly for all flexion angles between cycle 0 and 50'000 (p = 0.39 to p = 0.89), except for 30° flexion, where a significant increase by 1.4 mm was found (p = 0.03). CONCLUSION: Increase in anteroposterior translation of knees treated with this dynamic augmentation procedure is low. The procedure maintains translation close to the immediate post-operative level over a simulated rehabilitation period of 50'000 gait cycles and therefore supports anterior cruciate ligament repair during biological healing.

Biomechanical comparison of plate and screw fixation in anterior pelvic ring fractures with low bone mineral density.

INTRODUCTION: Osteosynthesis of anterior pubic ramus fractures can be challenging, especially in poor bone quality. The aim of the present study was to compare plate and retrograde endomedullary screw fixation of the superior pubic ramus with low bone mineral density (BMD). MATERIALS AND METHODS: Twelve human cadaveric hemi-pelvises were analyzed in a matched pair study design. BMD of the specimens was 35±30mgHA/cm(3), as measured in the fifth lumbar vertebra. A simulated two-fragment superior pubic ramus fracture model was fixed with either a 7.3-mm cannulated retrograde screw (Group 1) or a 10-hole 3.5-mm reconstruction plate (Group 2). Cyclic progressively increasing axial loading was applied through the acetabulum. Relative interfragmentary movements were captured using an optical motion tracking system. RESULTS: Initial axial construct stiffness was 424±116.1N/mm in Group 1 and 464±69.7N/mm in Group 2, with no significant difference (p=0.345). Displacement and gap angle at the fracture site during cyclic loading were significantly higher in Group 1 compared to Group 2. Cycles to failure, based on clinically relevant criteria, were significantly lower in Group 1 (3469±1837) compared to Group 2 (10,226±3295) (p=0.028). Failure mode in Group 1 was characterized by screw cutting through the cancellous bone. In Group 2 the specimens exclusively failed by plate bending. CONCLUSIONS: From biomechanical point of view, pubic ramus stabilization with plate osteosynthesis is superior compared to a single retrograde screw fixation in osteoporotic bone. However, the extensive surgical approach needed for plating must be considered.

Elective implant removal in symptomatic patients after internal fixation of proximal humerus fractures improves clinical outcome.

BACKGROUND: Operative treatment is the standard for severely displaced proximal humerus fractures, but functional impairment can persist. Retaining of the implant can be a reason and in other fracture situations has proved to ameliorate patient satisfaction. The aim of this study was to analyse the functional outcome after locking plate removal in proximal humerus fractures. METHODS: In a two-year period, all symptomatic patients with plate osteosynthesis for proximal humerus fracture and hardware removal were retrospectively evaluated clinically and radiologically pre- and post-implant removal. Evaluation included Constant score, height of plate position and possible impingement, as well as intraoperative complications. RESULTS: Twenty patients met the inclusion criteria. The mean age was 56 ± 12 years. The plates were placed 6.9 ± 3 mm distal to the greater tubercle. The operation was performed in 35 ± 10 min and no intraoperative complications were reported. The Constant score improved significantly after implant removal from 71 to 76 (p = 0.008). CONCLUSION: Symptomatic patients after locked plate osteosynthesis for proximal humerus fractures showed statistically significant improvement of the Constant score after implant removal.

Prospective clinical and radiostereometric analysis of the Fitmore short-stem total hip arthroplasty.

INTRODUCTION: Uncemented short, curved femoral stems may help save proximal bone stock during total hip arthroplasty (THA) and facilitate insertion in minimal invasive surgery. The aim of this 2 year, prospective, single-center study was to examine the stability and migration of the Fitmore (®) stem in THA using model-based radiostereometric analysis (RSA), and thus predict the implant's long-term survival. In addition, we evaluated the stem's clinical performance using standard clinical measures. PATIENTS AND METHODS: We conducted a prospective cohort study of 34 THA patients who received the short Fitmore Hip Stem (Zimmer, Winterthur, Switzerland). At 3, 6, 12 and 24 months postoperatively, the patients underwent clinical evaluation and radiostereometric analysis (RSA) to measure stem migration. RESULTS: RSA analysis revealed a mean subsidence of -0.39 mm (95 % CI -0.60 to -0.18) at 3 months with no further migration after 2 years. Mean internal rotation along the longitudinal axis was 1.09° (95 % CI 0.52-1.66) at 2 years, versus 0.85° (95 % CI 0.44-1.26) at 3 months. The Harris hip score improved from 60 (range 30-80) preoperatively to 99 (range 83-100) after 2 years. Three patients underwent revision due to deep infection, non-specific thigh pain and aseptic loosening in one case. CONCLUSION: We conclude that the Fitmore Hip Stem stabilizes after 3 months and achieves good short-term clinical results in most cases.

Controlled dynamic stability as the next step in "biologic plate osteosynthesis" - a pilot prospective observational cohort study in 34 patients with distal tibia fractures.

INTRODUCTION: Delayed bone healing is an eminent problem in the operative treatment of distal tibia fractures. To address this problem from a biomechanical perspective, the DLS 3.7 (Dynamic Locking Screw 3.7 mm) as a new generation of locking screws has been developed. This screw enables the surgeon to control the rigidity of the plate osteosynthesis and thereby to expand clinical options in cases where the bridge plating is chosen for fracture treatment. PURPOSE: The purpose of the present prospective study was to evaluate the safety use of the DLS 3.7 in distal tibia fractures where bridge plating osteosynthesis is recommended. METHODS: In a prospective non-controlled cohort study, 34 patients with acute distal tibia fractures (AO 43 A-C) were treated with an angular stable plate fixation using DLS 3.7 or LHS 3.5. Follow-up examinations were performed three, six, twelve, and twenty-four weeks postoperatively and all registered complications were carefully collected. RESULTS: A total of 34 patients were prospectively enrolled in this study with a minimum follow-up of 6 months or obvious osseous consolidation at an earlier stage. No complications directly related to the DLS 3.7 were recorded and no infections were observed. CONCLUSIONS: This observational study could show that the DLS 3.7 in combination with locking compression plates provides a secure and easy application. According to the recent literature inter-fragmentary micro-motion is one evident goal to increase the reliability in fracture healing. The new DLS 3.7 with a maximum micro-motion of 0.2 mm combines the advantage of micro-motion with the well-known advantages of angular stable plate fixation.

[Pediatric supracondylar fractures of the humerus]. / Suprakondyläre Humerusfrakturen im Kindesalter.

Supracondylar fractures are on the of the most common injuries in paediatric patients. Therapeutic consequences depend on the one hand on the degree of the osseous displacement according to the Gartland classification. On the other hand, the diagnosis of concomitant neuro-vascular injuries is crucial to prevent long term impairment. Never the less, clinical diagnosis can be challenging. In-depth knowledge of pediatric supracondylar humerus fractures is a prerequisite to achieve a functionally and cosmetically satisfactory long-term outcome.

A prospective analysis of the functional and radiological outcomes of minimally invasive plating in proximal humerus fractures.

BACKGROUND: Locking-plate osteosynthesis is a well-established treatment option for proximal humerus fractures. The standard approach is delta-pectoral, but few data using the minimally invasive antero-lateral delta-split approach exist. The aim of the study was to prospectively evaluate shoulder function and radiological outcome after a minimally invasive antero-lateral delta-split approach. MATERIALS AND METHODS: From December 2007 to October 2010, 124 patients with proximal humerus fractures were treated with locking-plate osteosynthesis using a minimally invasive antero-lateral delta-split approach. Complete prospective clinical and radiographic data were available for 97 patients for a minimum 1-year follow-up period. RESULTS: After a follow-up period of 18 ± 6 months, the patients achieved a mean absolute Constant score of the injured shoulder of 75 ± 11, equalling 91% of the contralateral shoulder Constant score (p < 0.01). Implant-related complications (e.g., screw perforation) were observed in seven patients (7.2%), and avascular necrosis occurred in eight patients (8.2%). Damage to the ventral branch of the axillary nerve was recorded in four cases (4%) without any clinical consequences. The mean delay between trauma and surgery was 0.5 days. The procedures were performed by a total of 16 surgeons who required an average of 73 ± 27 min of OR time and 108 ± 121 s of fluoroscopy time. CONCLUSIONS: Minimally invasive osteosynthesis using angle-stable implants for proximal humerus fractures demonstrated good functional results. Compared to the literature, this minimally invasive procedure resulted in a shorter operation time and may have reduced the avascular necrosis rate. LEVEL OF EVIDENCE: Level IIb, monocentric prospective cohort study.

Compartment syndrome in dislocation and non-dislocation type proximal tibia fractures: analysis of 356 consecutive cases.

INTRODUCTION: Dislocation type proximal tibia fractures are associated with the major soft tissue injuries. The main purpose of this study was to analyze the incidence of compartment syndrome (CS) in proximal tibia fractures in relation to the fracture type, i.e., dislocation versus non-dislocation type. We further analyzed CS within the non-dislocation type injuries, initial treatment modality as well as infection rate relative to the treatment policies (one- or two-staged procedures). PATIENTS AND METHODS: Over an 8.5-year period, prospectively, acquired data of 356 proximal tibia fractures were evaluated. All fractures were classified either according to the AO/OTA or to the Moore (fracture dislocation type) classification system respectively. The appearance of CS in dislocation and non-dislocation type injuries as well as treatment modality, i.e., one- or two-staged procedures was analyzed. RESULTS: 307 (86%) fractures were classified as non-dislocation type and 49 (14%) as fracture dislocation type injuries. Overall 31 (8.7%) CS occurred. All were diagnosed and treated within the initial surgical management. CS was equally distributed in non-dislocation type fractures (24/307) and Moore type fractures (7/49) (Chi-square test, p = 0.4). But a significant difference in the non-dislocation type injuries was observed between AO/OTA B-type (0/166) and non-B type fractures (24/117) (Chi-square test, p < 0.001). 104 fractures were treated in a two-staged procedure with definitive reconstruction after an average of 6.0 days. Initial postoperative surgical site infection remained very low with 0.5%, and did not seem to be related to operative treatment variables including single-stage versus two-stage reconstruction, temporary external fixation and/or compartment fasciotomies. CONCLUSION: The incidence for CS did not differ between the dislocation and non-dislocation type group, but a significant difference was found comparing the incidence for CS only in the non-dislocation type group.

Operative strategy in postero-medial fracture-dislocation of the proximal tibia.

OBJECTIVE: In 1981, Moore introduced a new classification for dislocation-type fractures caused by high-energy mechanisms. The most common medial Moore-type fractures are entire condyle fractures with the avulsion of the median eminence (tibial anterior cruciate ligament (ACL) insertion). They are usually associated with a posterolateral depression of the tibial plateau and an injury of the lateral menisco-tibial capsule. This uniform injury of the knee is increasingly observed in the recent years after skiing injuries due to the high-speed carving technique. This uprising technique uses shorter skis with more sidecut allowing much higher curve speeds and increases the forces on the knee joint. The aim of this study was to describe the injury pattern, our developed operative approach for reconstruction and outcome. METHODS: A total of 28 patients with 29 postero-medial fracture dislocation of the proximal tibia from 2001 until 2009 were analysed. Clinical and radiological follow-up was performed after 4 years on average (1 year in minimum). Evaluation criteria included the Lysholm score for everyday knee function and the Tegner score evaluating the activity level. All fractures were stabilised post primarily. The surgical main approach was medial. First, the exposure of the entire medial condyle fracture was performed following the fracture line to the articular border. The posterolateral impaction was addressed directly through the main fracture gap from anteromedial to posterolateral. Small plateau fragments were removed, larger fragments reduced and preliminarily fixed with separate K-wire(s). The postero-medial part of the condyle was then prepared for main reduction and application of a buttress T-plate in a postero-medial position, preserving the pes anserinus and medial collateral ligament. In addition, a parapatellar medial mini-arthrotomy through the same main medial approach was performed. Through this mini-arthrotomy, the avulsed anterior eminence with attached distal ACL is retained by a transosseous suture back to the tibia. RESULTS: We could evaluate 26 patients (93%); two patients were lost to follow-up due to foreign residence. Median age was 51 years (20-77 years). The fractures were treated post primarily at an average of 4 days; in 18 cases a two-staged procedure with initial knee-spanning external fixator was used. All fractures healed without secondary displacement or infection. As many as 25 patients showed none to moderate osteoarthritis after a median of 4 years. One patient showed a severe osteoarthritis after 8 years. All patients judge the clinical result as good to excellent. The Lysholm score reached 95 (75-100) of maximal 100 points and the Tegner activity score 5 (3-7) of maximal 10 points (competitive sports). The patients achieved a median flexion of 135° (100-145°). CONCLUSION: In our view, it is crucial to recognise the different components of the injury in the typical postero-medial fracture dislocation of the proximal tibia. The described larger medial approach for this type of medial fracture dislocation allows repairing most of the injured aspects of the tibial head, namely the medial condyle with postero-medial buttressing, the distal insertion of the ACL and the posterolateral impaction of the plateau.

Unexpectedly increased rate of surgical site infections following implant surgery for hip fractures: problem solution with the bundle approach.

INTRODUCTION: Surgical site infections (SSIs) are the most common nosocomial infections after surgery.However, clinical guidance on how to handle any suspicious clusters of SSI in orthopaedic surgery is missing. We report on problem analysis and solution finding following the observation of an increased rate of SSI in trauma implant surgery. SETTING: Trauma unit of a university hospital. METHODS: Over a 2-year observation period, all patients (n = 370) following surgical stabilisation of proximal femur fractures in a trauma unit of a university hospital were consecutively followed using a standardised case report form. First, a retrospective cohort of 217 patients was collected for whom an increased SSI rate was detected. Based on risk analysis, new standard perioperative procedures were developed and implemented. The impact was evaluated in a prospective cohort of 153 comparable patients. Uni- and multivariable analysis of factors associated with the risk for SSI was undertaken. RESULTS: The intervention bundle resulted in a significant reduction of an initially increased SSI incidence of 6.9 (down) to 2.0% (p = 0.029). Multivariable analysis revealed four risk factors significantly associated with a higher risk of SSI caused by different bacteria: duration of surgery (p = 0.002), hemiarthroplasty(p = 0.002), haematoma (p = 0.004) and the presence of two operating room staff members (p < 0.001 and 0.035). CONCLUSIONS: A standardised prospective SSI protocol and detection system offering the simultaneous use of data should guarantee every institution immediate alarm registration to avoid comparable problem situations. Detailed interdisciplinary analysis followed by the implementation of coherent interventions, based on a best-evidence structured bundle approach, may adequately resolve similar critical incidence episodes.

Minimal Invasive PHILOS(®)-Plate Osteosynthesis in Proximal Humeral Fractures.

INTRODUCTION: The anterior delto-pectoral approach is the standard approach for the fixation of proximal humeral fractures with the PHILOS(®)-Plate system. However, this approach can impair the vascular supply and can increase avascular necrosis. The objective of this study was to evaluate the results and complexity of surgery of proximal humeral fractures with a minimal invasive (MIPO) approach. METHODS: All PHILOS(®)-plate osteosynthesis operated between Januray 2003 and June 2006 were evaluated prospectively. A minimal invasive antero-lateral deltasplit-approach was performed in all two to four fragment instable fractures meeting the indication for osteosynthesis according to Neer. An open approach (ORIF) was chosen in all other fractures mainly dislocated fractures and particularly in fractures with major subcapital displacement. RESULTS: A cohort of 68 patients suffered a proximal humerus fracture and qualified for a minimal invasive approach with a PHILOS(®)-plate osteosynthesis. Of these 68 patients, 41 were locally resident. Eight patients refused a follow-up, two patients were in constant care, and two patients died; 29 patients (71%) (20 females, 9 males) could be documented entirely with a median age of 64 years. The median operation time amounted to 75 min with a fluoroscopic time of 160 s. The median Constant score was 78 after 12 months. All fractures healed in adequate time. One patient showed a lesion of the ventral part of the axillary nerve. No patient suffered an avascular necrosis. DISCUSSION: The minimal invasive PHILOS(®) plate osteosynthesis through an antero-lateral delta-split approach proved to be an elegant procedure for selected fractures of the proximal humerus with a low morbidity and good functional outcome.