Gertraud Gradl

Unstable Intertrochanteric Femur Fractures: Is There a Consensus on Definition and Treatment in Germany?

BackgroundExtramedullary 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/purposesWe 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.MethodsBetween 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%.ResultsThere 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.ConclusionsDespite 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.Level of EvidenceLevel V, expert opinion. See the Instructions for Authors for a complete description of levels of evidence.

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.

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.

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 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.

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.

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.

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.

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.

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.