Displaced intra-articular calcaneal fractures: is there a consensus on treatment in Germany?

INTRODUCTION: Open reduction in displaced intra-articular calcaneal fractures entails a high rate of wound healing deficits and infections as well as an uncertain outcome, which leads to remaining ambiguity in treatment preferences. METHODS: Between January and July 2011, we emailed 575 German chairpersons of trauma and/or orthopaedic departments, asking them to complete a 31-question web-based survey regarding three broad domains: fracture classification, surgical treatment algorithms and risk factors for wound healing deficits. RESULTS: The response rate was 47 %. With an incidence of 77 %, open reduction via an extended lateral approach and plate fixation was the main treatment option for displaced intra-articular fractures of the joint-depression-type (Sanders II or III). Percutaneous techniques were only preferred in individual cases, with mainly precarious wound situations (59 %) as well as in patients with a reduced general health condition (ASA 3 and 4; 41 %). The re-operation rate due to infections and wound healing deficits after an extended lateral approach was reported with a percentage of 0-5 % by 88 % of the respondents. Participants stated that especially a poor microcirculation of the foot, disregard of soft tissue conserving techniques, overall condition of the patient, smoking, long time-to-surgery and operation time are the main reasons for wound healing deficits. CONCLUSION: Given the extended lateral approach as the preferred treatment option, we found minimally invasive techniques and primary arthrodesis of the lower ankle joint play a minor role in treating intra-articular calcaneal fractures in Germany. Ninety percent of our respondents stated less than 5 % of patients required re-operations due to infections and wound healing deficits. Level of Evidence Level V, expert opinion.

Decision making in displaced fractures of the proximal humerus: fracture or surgeon based?

PURPOSE: The aim of this study was to analyse the factors that influence surgeon decision-making in the treatment of proximal humerus fractures that might be considered for arthroplasty or open reduction and internal fixation. METHODS: A total of 217 surgeons evaluated radiographs and clinical vignettes of ten patients with fractures of the proximal humerus. In addition to radiographs, we provided patient age, sex, trauma mechanism, activity level (sedentary-vigorously active), and physical status (normal healthy-moribund). Observers were asked to: (1) choose open reduction and internal fixation or hemiarthroplasty (closed question, one option) and (2) to briefly describe the factors that led to their decision (open-ended question). We assessed interobserver reliability using the Fleiss generalized kappa and analysed factors that influenced decision-making according to treatment choice. RESULTS: Internal fixation was the preferred treatment for the majority of fractures. The overall multirater agreement was fair (κ = 0.30), with a 75 % proportion of agreement. When asked to describe the factors that influenced decision-making, surgeons favouring internal fixation described patient-based factors in 52 %, fracture morphology in 51 %, surgeon factors in 42 %, and bone quality in 11 %. In contrast, fracture morphology was the most common factor (67 %) described by surgeons recommending replacement. Patient age, sex, activity level, physical status and the presence of angular displacement were associated with a recommendation for internal fixation. CONCLUSION: There is substantial variation in recommendations for internal fixation vs. arthroplasty for fractures of the proximal humerus that arises in large part from patient and surgeon factors.

Is percutaneous suturing superior to open fibrin gluing in acute Achilles tendon rupture?

PURPOSE: Open fibrin gluing is reported to enable anatomical reconstruction with less soft tissue compromise than suture repair. Our main objective was to compare the complication rate, function, pain and disability of the two operative approaches of percutaneous suture using the Paessler technique and open fibrin gluing. METHODS: Sixty-four patients (two centres, retrospective cohort study, 2000-2009) who had undergone acute Achilles tendon repair with either percutaneous suture (n = 27; 44 years) or open fibrin glue (n = 37; 45 years) took part in a follow-up examination after a median of 63 months (range, six to 180). Ankle range of motion, calf and ankle circumferences and return to work and sports activities were evaluated. Isokinetic und sonographic evaluation results were retrieved. RESULTS: Complications were noted in 22 patients (34 %). Delayed wound healing without evidence of surgical site infection was found in three patients in the fibrin group and two patients in the suture group. Postoperative scar tenderness described as pain at the rim of the shoe was significantly more frequent in the suture group (p = 0.03). Re-rupture requiring re-operation occurred in one patient. Transient paresthesia of the heel occurred in 12 patients. No sural nerve lesions were reported. There was no significant difference between groups regarding lower leg circumference, disability, or function. Ultrasound and isokinetic measurements did not reveal a significant difference between the two methods. CONCLUSIONS: The present study suggests that open fibrin gluing is a reasonable alternative to percutaneous repair of acute ruptures of the Achilles tendon and both techniques can yield reliably good results.

Unstable intertrochanteric femur fractures: is there a consensus on definition and treatment in Germany?

BACKGROUND: Extramedullary and intramedullary implants have improved in recent years, although consensus is lacking concerning the definition and classification of unstable intertrochanteric fractures, with uncertainties regarding treatment. QUESTIONS/PURPOSES: We conducted a national survey of practicing chairpersons of German institutions to determine current perspectives and perceptions of practice in the diagnosis, management, and surgical treatment of unstable intertrochanteric fractures. METHODS: Between January and February 2010, we emailed 575 German chairpersons of trauma and/or orthopaedic departments, asking them to complete a 26-question web-based survey regarding three broad domains: fracture classification and instability criteria, implants and surgical treatment algorithms, and timing of operations. Response rate was 42%. RESULTS: There was a clear preference for use of the AO/OTA fracture classification with geographic variations. Absence of medial support was considered the main criterion for fracture instability (84%), whereas a broken lateral wall and detached greater trochanter were considered by 4% and 5% of the respondents, respectively, to determine instability. Two percent routinely fixed unstable intertrochanteric fractures with extramedullary devices. Ninety-eight percent of German hospitals reportedly perform surgery within 24 hours after admission. Time to surgery was dependent on hospital level, with more direct surgeries in Level I hospitals. CONCLUSIONS: Despite varying opinions in the literature in recent years, we found some instability criteria (lateral wall breach, a detached greater trochanter) played a minor role in defining an unstable intertrochanteric fracture pattern. Despite recent meta-analyses suggesting clinical equivalence of intra- and extramedullary implants, few respondents routinely treat unstable intertrochanteric fractures with extramedullary plates. Additional studies are required to specify the influence of fracture characteristics on complication rate and function and to establish a classification system with clear treatment recommendations for unstable intertrochanteric fractures.

Radiographic diagnosis of scapholunate dissociation among intra-articular fractures of the distal radius: interobserver reliability.

PURPOSE: To evaluate the reliability and accuracy of diagnosis of scapholunate dissociation (SLD) among AO type C (compression articular) fractures of the distal radius. METHODS: A total of 217 surgeons evaluated 21 sets of radiographs with type C fractures of the distal radius for which the status of the scapholunate interosseous ligament was established by preoperative 3-compartment computed tomographic arthrography with direct operative visualization of diagnosed SLD (reference standard). Observers were asked whether SLD was present, and if yes, whether they would recommend operative treatment. Diagnostic performance characteristics were calculated with respect to the reference standard. We assessed interobserver reliability using the Fleiss generalized kappa. RESULTS: The interobserver agreement for radiographic diagnosis of SLD was moderate (κ = 0.44). Correct diagnosis for a given set of radiographs ranged from 8% to 98% (average, 79%) of observers. Diagnostic performance characteristics were: 69% sensitivity, 84% specificity, 84% accuracy, 68% positive predictive value, and 84% negative predictive value. Based on a prevalence of 5%, Bayes adjusted positive and negative predictive values were 18% and 98%, respectively. Raters recommended operative treatment in 74% to 100% of patients diagnosed with SLD. CONCLUSIONS: Radiographs are moderately reliable and are better at ruling out than ruling in SLD associated with type C fracture of the distal radius.

Corrective osteotomy of the distal radius following failed internal fixation.

INTRODUCTION: The purpose of this study was to quantify the clinical and radiographic outcomes after corrective osteotomy for malunions of the distal radius following failed internal fixation. MATERIALS AND METHODS: Results of 18 patients (8 women, 10 men; mean age 41 years) are presented an average of 7 years after osteotomy of a malunited distal radius fracture. We assessed active range of motion, grip strength, radiographic alignment, pain and disability. Subjective and objective data were summarized using the modified Mayo Wrist Score and the point-score system of Fernandez. RESULTS: Wrist motion, pain and deformity improved with the operation in all cases. The modified Mayo Wrist Score averaged 79 points. The scale of Fernandez indicated ten good, two fair and six poor results. CONCLUSIONS: The results of this study suggest that the operative correction of a distal radius malunion following an unsuccessful internal fixation can be achieved with outcomes comparable to those reported after initial nonoperative treatment.

Non-bridging external fixation employing multiplanar K-wires versus volar locked plating for dorsally displaced fractures of the distal radius.

BACKGROUND: The aim of this study was to compare non-bridging external fixation to palmar angular stable plating with respect to radiological outcome, wrist function, and quality of life. METHODS: One hundred and two consecutive patients (mean age: 63 years) were enrolled in the study. Fifty-two patients were randomized for plate osteosynthesis (2.4 mm, Synthes), 50 patients received non-bridging external fixation (AO small fixator). Objective (range of motion, grip strength), patient rated outcomes (quality of life, pain), and radiological outcome were assessed 8 weeks, 6 months, and 1 year after surgery. RESULTS: Loss of radial length of more than 3 mm was not detected in any group. Volar tilt was better restored by external fixation (7.2°) than by volar plating (0.1°). Wrist function was good in both groups. The external fixator was tolerated very well, and the quality of life assessment revealed comparable results in both groups. Osteoporosis was found in 54 % of patients and had no influence on radiological and functional outcome. CONCLUSION: Non-bridging external fixation employing multiplanar K-wires is a suitable treatment option in intra- and extra-articular fractures of the distal radius even in osteoporotic bone.

The functional outcome of acute scapholunate ligament repair in patients with intraarticular distal radius fractures treated by internal fixation.

BACKGROUND: Intra-articular fractures of the distal radius (DRF) are associated with a twofold increase in the risk of scapholunate ligament injury (SLI). The aim of this study was to compare functional outcome, pain, and disability between patients with operatively treated DRF and either an acute, repaired scapholunate ligament injury or no ligament injury. METHODS: We retrospectively analyzed 18 patients with an intraarticular DRF and SLI that was diagnosed and treated (Group I) and compared them with 20 patients with DRF without associated ligament injury (Group II) (20 women, 18 men; average age 55 years, range 19-72). The two cohorts were analyzed for differences in motion, grip strength, pain, Mayo wrist score, and Quick Disabilities of the Arm, Shoulder, and Hand (DASH) score an average of 43 months (range 12-73) after surgery. Radiographic assessment included fracture union, palmar tilt, radial inclination, ulnar variance, intercarpal angles, and arthrosis (according to Knirk and Jupiter). We used T-tests to compare range of motion, grip strength, pain (visual analog scale), DASH scores, and radiographic alignment between cohorts. A Chi-squared analysis was used to determine radiographic differences of arthritis. RESULTS: There were no significant differences in mean range of motion, grip strength, Quick DASH score, Mayo wrist score, pain level, or radiographic arthrosis between cohorts. There was no correlation between radiographic signs of osteoarthritis and the QuickDASH score, and pain level. CONCLUSION: The outcomes of intraarticular fractures of the distal radius with operatively treated associated SLI are comparable with the outcomes of intraarticular fractures of the distal radius without associated SLI.

Radiographic changes in the operative treatment of acute acromioclavicular joint dislocation - tight rope technique vs. K-wire fixation.

BACKGROUND: Operative treatment of higher degree acromioclavicular joint luxation is common. A new option is made available by the tight rope technique. It claims to provide adequate outcome with the use of a minimally invasive technique. First clinical studies justified its medical use, but the equivalence to established surgical methods remains unclear. We therefore analyzed radiographic data from patients that were treated with the tight rope system (TR) and compared them to those treated with K-wires (KW) fixation. MATERIAL/METHODS: RETROSPECTIVE STUDY WITH INCLUSION CRITERIA: surgery for acromioclavicular joint luxation between 2004 and 2011, classified as Rockwood type III, no concomitant injury, first event injury. We compared pre- and post-operative X-rays with those taken at the end of treatment. Clinical data from follow-ups and radiographic data were evaluated. The main outcome variable was the remaining distance between the acromion and clavicle (ACD), as well as the coracoid process and clavicle (CCD). RESULTS: 27 patients (TR: n=16; KW: n=11) with comparable demographics and injury severity were included. Surgery reduced ACD (TR: p=0.002; KW: p<0.001) and CCD (TR: p=0.001; KW: p=0.003). Heterotopic ossification or postoperative osteolysis was not significantly associated with either one of the procedures. Three patients (18.75%) in the TR group showed impaired wound healing, migrating K-wires were recorded in 2 patients (18.2%) and impingement syndrome occurred in 1 patient (9.1%) with K-wires. Posttraumatic arthritis was not seen. There was a loss of reduction in 2 cases within the TR-group (12.51%) and 1 in the KW-group (9.1%). At last follow up, ACD and CCD were wider in both groups compared to the healthy side. CONCLUSIONS: This study shows that the Tight rope system is an effective alternative in the treatment of higher degree acromioclavicular luxation and comparable to the established methods.

Microcirculation After Trochanteric Femur Fractures: A Prospective Cohort Study Using Non-invasive Laser-Doppler Spectrophotometry.

Proximal femur fractures represent a major healthcare problem in the aging society. High rates of post-operative infections are linked to risk factors that seem to affect local microcirculation. Patterns and time courses of alterations in microcirculation have, however, not been previously investigated. The aim of this prospective cohort study was to evaluate perioperative changes in microcirculation after trochanteric femur fractures using non-invasive laser-Doppler spectrophotometry to analyze how oxygen saturation (SO2), hemoglobin content (Hb) and blood flow changed before and after surgery, and how these parameters were altered by implant type, gender, smoking, diabetes and age. Measurements were separately recorded for nine locations around the greater trochanter in 2, 8, and 15 mm depths, before surgery and 8, 24, 48 h, 4, 7, and 12 days after surgery in 48 patients. Three implants were compared: Dynamic Hip Screw, Gamma3 Nail, and Percutaneous Compression Plate. Surgery resulted in significant differences between the healthy and injured leg in SO2, Hb and flow. Each parameter showed comparable values for both legs prior to surgery. Significantly higher values in SO2 and flow were registered in women compared to men before and after surgery. Smoking caused significant increases in SO2, Hb, and flow only in the superficial layer of the skin after surgery. Diabetes decreased blood flow at 2 and 8 mm depth and increased SO2 at 8 and 15 mm depth after surgery. Age revealed a significant negative correlation with flow. The ability to increase the flow rate after surgery decreased with age. Comparison of implants indicated the minimally invasive implant PCCP altered microcirculation less than the DHS or the Gamma3 nail. Overall, the proximal femur fracture alone did not alter local skin microcirculation significantly in a way comparable to the effect caused by surgery. In conclusion, microcirculation after proximal femur fractures is highly affected by surgery, gender, smoking, diabetes, age and implant in ways specified in this study.

Extra-articular scapular fractures: comparison of theoretical and actual treatment.

BACKGROUND: Discrete radiographic thresholds of scapular fracture deformity proposed as a guide for when to utilize operative treatment are a matter of debate. The purpose of the present study was to determine how many patients would have received operative treatment according to these criteria and how many actually received operative treatment. METHODS: Three hundred and thirty patients with an extra-articular fracture of the scapula at two level 1 trauma centers were retrospectively analyzed. Glenopolar angle, translation, angulation and medial/lateral displacement were measured on computed tomogaphy scans or radiographs to determine the theoretical operative treatment recommendation according to Cole's criteria. RESULTS: Sixty-two patients (19%) had one or more radiographic indications for operative treatment, half of them had more than 20 mm of lateral displacement, and one fourth of them had substantial translation. No patients had operative treatment of the scapular body. Two patients had operative treatment of an acromion fracture, neither of which met radiographic criteria for surgery. CONCLUSIONS: At least in our centres, there is a striking discrepancy between theoretical and actual recommendations for surgery. There is clearly a need for more research to determine whether patients are being undertreated or whether the guidelines are too stringent.

Fixation of intra-articular fractures of the distal radius using intramedullary nailing: a randomized trial versus palmar locking plates.

BACKGROUND: Proposed benefits of intramedullary techniques include limited soft tissue dissection while affording sufficient stability to allow early wrist motion. The primary null hypothesis of this randomized trial was that there is no significant difference with respect to functional outcome, pain and disability between patients treated with either 2.4-mm volar locking plate fixation or intramedullary nail fixation of intra-articular fractures of the distal radius. METHODS: We conducted a single-centre, prospective randomized matched-pairs trial. Patients with intraarticular distal radius fractures with metaphyseal comminution and a sagittal fracture line (AO 23 C2.1) were randomized to receive volar locking plate fixation (n = 14) or intramedullary nailing (n = 14). The outcome was measured on the basis of the Gartland and Werley and Castaing score; the pain level; the range of wrist motion; the rate of complications; and radiographic measurements including volar tilt and ulnar variance. Clinical and radiographic assessment was performed at 8 weeks and 2 years after the operation. RESULTS: There were no significant differences between groups in terms of range of motion, grip strength or the level of pain at eight weeks. At the final follow up, patients in the nail group had regained more extension than in the plate group (98% of the unaffected side vs. 94%, this however, did not reach significance). Reduction was maintained in both groups; however volar tilt and ulnar variance were significantly better in the plate group. There was no significant difference in the complication rate between groups. CONCLUSION: The present study suggests that intramedullary nail fixation is a reasonable alternative to volar plate fixation for the treatment of intra-articular distal radius fractures and both techniques can yield reliably good results.

Rotationally Stable Screw-Anchor With Locked Trochanteric Stabilizing Plate Versus Proximal Femoral Nail Antirotation in the Treatment of AO/OTA 31A2.2 Fracture: A Biomechanical Evaluation.

OBJECTIVES: Third-generation cephalomedullary nails currently represent the gold standard in the treatment of unstable trochanteric femur fractures. Recently, an extramedullary rotationally stable screw-anchor system (RoSA) has been developed. It was designed to combine the benefits of screw and blade and to improve stability using a locked trochanteric stabilizing plate (TSP). The purpose of this study was to compare the biomechanical behavior of RoSA/TSP and the proximal femoral nail antirotation (PFNA). METHODS: Standardized AO/OTA 31A2.2 fractures were induced by an oscillating saw in 10 paired human specimens (n = 20; mean age = 85 years; range: 71-96 years). The fractures were stabilized by either the RoSA/TSP (Koenigsee Implants, Allendorf, Germany) or the PFNA (DePuy Synthes, Zuchwil, Switzerland). Femurs were positioned in 25 degrees of adduction and 10 degrees of posterior flexion and were cyclically loaded with axial sinusoidal pattern at 0.5 Hz, starting at 300 N, with stepwise increase by 300 N every 500 cycles until bone-implant failure occurred. After every load step, the samples were measured visually and radiographically. Femoral head migration was assessed. RESULTS: The stiffness at the load up to the clinically relevant load step of 1800 N (639 ± 378 N/mm (RoSA/TSP) vs. 673 ± 227 N/mm (PFNA); P = 0.542) was comparable, as was the failure load (3000 ± 787 N vs. 3780 ± 874 N; P = 0.059). Up to 1800 N, no femoral head rotation, head migration, or femoral neck shortening were observed either for RoSA/TSP or PFNA. Whereas failure of the PFNA subsumed fractures of the greater trochanter and the lateral wall, a posterior femoral neck fracture with a significantly increased femoral neck shortening (1.7 mm vs. 0 mm; P = 0.012) was the cause of failure with RoSA/TSP. This specific kind of failure was induced by a femoral neck weakening caused by the posterior TSP stabilizing screw. CONCLUSIONS: There was no significant difference in biomechanical properties between the RoSA/TSP and the PFNA for the fracture pattern tested. However, failure modes differed between the 2 implants with greater femoral neck shortening observed in the RoSA/TSP group.

A comparison of actual and theoretical treatments of glenoid fractures.

BACKGROUND: There is no consensus on the operative treatment of glenoid fractures. The purpose of this study was to see whether there was a difference between how patients with a glenoid fracture would receive treatment according to theoretical operative indications based on the measurement of computed tomography (CT) scans and radiographs and the treatment they actually received in our institutions. METHODS: A total of 457 patients with a scapular fracture were treated in two level 1 trauma centres between January 2002 and August 2011. Ninety-eight patients with a glenoid fracture were retrospectively analyzed. Intra-articular gap, medial or lateral (M/L) displacement, angular deformity, and glenopolar angle (GPA) were measured on CT scans or radiographs to determine theoretical indications for operative treatment. RESULTS: Twenty-four patients (25%) actually had operative treatment, while 35 patients (36%) fulfilled at least one theoretical criterion to proceed with operative treatment with a medium correlation between theoretical indications for surgery and the actual operative treatment. All the patients with a theoretical indication for surgery had an intra-articular gap with a step-off of >4 mm. A bony Bankart lesion with shoulder dislocation and injury in sports was retained in the best multivariable model as indications for the actual surgery. CONCLUSION: Theoretical guidelines for surgery on glenoid fractures may not have much influence on the current treatment. LEVEL OF EVIDENCE: Therapeutic, level III.

Locked minimally invasive plating versus fourth generation nailing in the treatment of AO/OTA 31A2.2 fractures: A biomechanical comparison of PCCP(®) and Intertan nail(®).

INTRODUCTION: Locked minimally invasive plating and fourth generation nailing potentially could reduce the complication rate in the treatment of trochanteric femur fractures by its rotational stability and providing better lateral cortical support. The purpose of this study was (1) to compare the biomechanical properties of the Percutaneous compression plate (PCCP) and the Intertan nail (IT) with regards to implant failure and (2) to assess dynamic stability coefficients in an unstable AO/OTA 31A2.2 fracture model. METHODS: In paired femurs, a standardised unstable trochanteric femur fracture was induced by an oscillating saw. The fractures were stabilised by either the PCCP (Orthofix, McKinney, TX, USA) or the IT (Smith & Nephew, Memphis, TN, USA). All femurs were loaded with 300N, followed by an increase in load until failure using 300N each time (2000 cycles each, 0.5Hz). After every load step the samples were assessed visually and radiographically. We measured migration and performed a survival analysis. RESULTS: 16 fractures were induced in 8 paired human specimens (mean age: 84 years, 61-100 years). The mean stiffness (PCCP vs. IT: 249±124N/mm vs. 273±153N/mm; p=0.737) was comparable. The IT proved superior to the PCCP with regard to the number of cycles reached before failure occurred (PCCP vs. IT: 12,691±4733 vs. 15,313±4875 cycles; p=0.023). Except for a higher axial migration of the IT at failure point (PCCP vs. IT: 1.3mm vs. 4.3mm; p=0.028) there were no differences between the intra- and extramedullary implants, not even in terms of rotational stability along the femoral neck axis. A fracture of the femoral neck caused test abortion in both implants in most cases. CONCLUSION: This study showed a superiority of the IT compared with the PCCP with regards to number of cycles achieved under sequential load increases for unstable trochanteric femur fractures. The stiffness was comparable. Both implants showed a high rotational stability and a support of the lateral wall. STUDY TYPE: Biomechanical study.

Intramedullary nail versus volar plate fixation of extra-articular distal radius fractures. Two year results of a prospective randomized trial.

BACKGROUND: Intramedullary techniques for stabilization of displaced distal radius fractures are now available. Purported benefits include limited soft tissue dissection while affording sufficient stability to allow early wrist motion. The primary null hypothesis of this randomized trial is that there is no significant difference with respect to functional outcome, pain and disability between patients treated with either 2.4-mm volar locking plate fixation or intramedullary nail fixation of unstable dorsally displaced extra-articular fractures of the distal radius. METHODS: We conducted a single-centre, parallel-group trial, with unrestricted randomization. Patients with dorsally displaced extra-articular distal radius fractures were randomized to receive volar locking plate (n=72) fixation or intramedullary nailing (n=80). The outcome was measured on the basis of the Gartland and Werley and Castaing score; the pain level; the range of wrist motion; the rate of complications; and radiographic measurements including volar tilt and ulnar variance. Clinical and radiographic assessment was performed at 8 weeks, 6 months, 1 year and 2 years after the operation. RESULTS: There were no significant differences between groups in terms of range of motion, grip strength or the level of pain during the entire follow-up period (p>0.05). There was no significant difference between treatment groups with respect to volar tilt or ulnar variance (p>0.05). There was no significant difference in the complication rate between groups (p>0.05). CONCLUSIONS: The present study supports the view that intramedullary nail fixation and volar plate fixation for the treatment of displaced extra-articular distal radius fractures have equivalent radiographic and functional outcomes. LEVEL OF EVIDENCE: Level I therapeutic study.

Surgical site infection in orthopaedic oncology.

BACKGROUND: This study addressed risk factors for surgical site infection in patients who had undergone orthopaedic oncology surgical procedures. METHODS: We retrospectively reviewed data on 1521 orthopaedic oncologic surgical procedures in 1304 patients. We assessed patient demographics, updated Charlson comorbidity index, surgery-specific data, and treatment-related data and attempted to identify predictors of surgical site infection with bivariate and multivariable analysis. RESULTS: Eight factors independently predicted surgical site infection: body mass index (odds ratio [OR]:, 1.03, 95% confidence interval [CI]: 1.00 to 1.07), age (OR: 1.18, 95% CI: 1.05 to 1.33), total number of preceding procedures (OR: 1.19, 95% CI: 1.07 to 1.34), preexisting implants (OR: 1.94, 95% CI: 1.17 to 3.21), infection at another site on the date of the surgery (OR: 4.13, 95% CI: 1.57 to 10.85), malignant disease (OR: 1.46, 95% CI: 0.94 to 2.26), hip region affected (OR: 1.96, 95% CI: 1.35 to 2.84), and duration of the procedure (OR: 1.16, 95% CI: 1.07 to 1.25). CONCLUSIONS: These factors can inform patients and surgeons of the probability of surgical site infection after orthopaedic oncologic surgery. While most risk factors are unmodifiable or related to the complexity of the case, infection at another site on the date of the surgery is one factor amenable to intervention.

Biomechanical evaluation of locking plate fixation of proximal humeral fractures augmented with calcium phosphate cement.

OBJECTIVES: To evaluate the influence of calcium phosphate cement augmentation on failure of locking plate fixation of proximal humeral fracture fixation in a cadaveric fracture model. METHODS: A 5-mm wedge osteotomy was created in each of 11 paired fresh-frozen human cadaveric humeri (age > 65 years). Specimens were randomly assigned to receive either locked plate fixation (group 1) or locked plate fixation with cement augmentation (group 2). Constructs were tested for axial stiffness, load to failure, and failure mode using a material testing machine. RESULTS: Cement-augmented specimens resisted higher loads (1936 ± 609 N) in comparison to nonaugmented specimens (1373 ± 590 N) (P = 0.01). In group 1, varus displacement and glenohumeral screw perforation occurred in all cases. Varus displacement occurred in 2 cases in group 2, whereas glenohumeral screw perforation did not occur in any of the cases. Cement augmentation led to a significant increase in axial stiffness (P = 0.04). CONCLUSIONS: Calcium phosphate cement-augmented locking plates enhanced fixation stability in proximal humeral fractures and reduced glenohumeral screw perforation in this 2-part cadaveric model. The ultimate advantage of this method remains to be determined in vivo.

Rotationally stable screw-anchor versus sliding hip screw plate systems in stable trochanteric femur fractures: a biomechanical evaluation.

OBJECTIVES: The rotationally stable screw-anchor plate system (RoSA) is unique in using a novel screw-blade combination. This investigation tested the hypothesis whether RoSA is advantageous over the sliding hip screw plate system (SHS) with regard to stiffness, failure load, displacement, and migration in stable trochanteric femur fractures (OTA 31A1.1). METHODS: Thirteen femur pairs (mean age = 79 years; range, 64-92 years) received implants of either the RoSA or SHS (Koenigsee Implants, Allendorf, Germany). Beginning with 300 N and under consecutive 300 N load-increase steps (2000 cycles, 0.5 Hz) the femurs were cycled until failure. Specimens were evaluated for fragment displacement in both frontal and rotational planes and for migration. A survival analysis was carried out. RESULTS: With regard to stiffness (526 ± 195 N/mm vs 358 ± 143 N/mm; P = 0.006) and the failure load (2838 ± 781 N vs 2262 ± 863 N; P = 0.012), the RoSA proved superior to the SHS. Furthermore, RoSA demonstrated higher rotational stability in comparison to the SHS (1800 N: 0 ± 0 degrees vs 1.1 ± 1.3 degrees; P = 0.015; failure point: 0 ± 0 degrees vs 2.3 ± 2.6 degrees; P = 0.008), measuring rotation about femoral neck axis over time. Whereas cutout occurred only in the RoSA system (n = 3; P = 0.110), the SHS underwent plastic deformation in 7 cases (n = 7; P = 0.003). In one case (7%), the insertion of the RoSA blade resulted in iatrogenic cut-through caused by a jamming of the screw and the blade. CONCLUSIONS: The fixation of stable trochanteric femur fractures with RoSA in cadavers led to greater primary stability under cyclic load, with significant advantages with regard to stiffness, failure load, and rotational stability, compared with the SHS. A detrimental effect was its migration tendency, which began at 1800 N and occurred in the cranial direction. A meticulous insertion technique was a prerequisite to avoid iatrogenic perforation of the femoral head. Our results will have to be substantiated by further biomechanical and clinical trials using an optimized RoSA system.

Locking plate fixation of humeral head fractures with a telescoping screw. A comparative biomechanical study versus a standard plate.

OBJECTIVES: Locking plate fixation of humeral head fractures bares the risk of glenohumeral screw penetration. In order to circumvent this problem it is recommended to insert shorter locking screws having at least a 6mm distance to the humeral head cortex. This in turn may reduce fixation stability and may lead to early varus displacement. One second frequent failure mechanism is cranial displacement of the greater tubercle. The study evaluates the biomechanical properties of a locking plate employing an additional telescoping screw that may enhance resistance to varus displacement. Screw in screw fixation of the greater tubercle may reduce the rate of cranial displacement. METHODS: In four paired fresh-frozen human cadaver humeri (age>70 years) a Neer IV/3 fracture was created with a 5mm osteotomy gap simulating metaphyseal comminution. Limbs were randomly assigned to receive plate fixation with an additional telescoping screw (Humerus Tele Screw: HTS) and on the contralateral limb Philos plate fixation before biomechanical evaluation (MTS-Bionix 858.2). Standard locking screws were placed in both groups 6mm below the radiological head circumference; the telescoping screw was placed in the subchondral layer. The greater tubercle was fixed with an additional screw in both techniques, in the HTS group the screw was anchored in the sleeve of the telescrew (screw in screw fixation). FINDINGS: Fixation stability with a mean stiffness of 300.9±28.8 N/mm in the HTS plate group proved to be significantly higher than in the Philos plate group (184.2±23.4 N/mm; p=0.006). The HTS plate also resisted higher loads in terms of fixation failure with loss of reduction at 290±58.6 N in comparison to 205±8.6 N for the Philos plate (p=0.2). Displacement of the greater tubercle occurred in no case of the HTS plate group and in two out of four cases in the Philos plate group. INTERPRETATION: The HTS plate provides high fixation stability in an in vitro humeral head fracture model and securely prevents displacement of the greater tubercle.