Modern osteosynthesis of periarticular fractures: The role of provisional fixation revisited.

Periarticular fractures are complex injuries affecting the joint articular surface, the subchondral area, the metaphyseal region, the surrounding soft tissue envelope and not infrequently the ligamentous structures. The management of these injuries has evolved over the years, from one stage to two stage procedures thus facilitating soft tissue resuscitation, adequate pre-operative planning and the use of biologics optimizing the conditions for definitive fixation for a successful long-term outcome. Provisional fixation constitutes an essential step in the surgical treatment of these fractures. Herein, the role of provisional fixation as well as strategies on how they should be applied are discussed. The aim is to revisit this important step of provisional fracture fixation since its introduction by Albin Lambotte, in the early 1900's.

No Difference in Conversion Rate to Hip Arthroplasty After Intramedullary Nail or Sliding Hip Screw for Extracapsular Hip Fractures: An Observational Cohort Study of 19,604 Individuals.

BACKGROUND: The widespread use of intramedullary nails (IMNs) compared with sliding hip screws (SHSs) in extracapsular hip fractures (AO/OTA 31-A1, 31-A2, 31-A3) has been questioned because of a higher complication rate, although the outcome might have improved through more recent implant designs and the learning curve. This study aimed to investigate if there is a difference with regard to the cumulative incidence of conversion to arthroplasty or any reoperation during the first 5 years after IMN or SHS fixation of extracapsular hip fractures. METHODS: In this nationwide, observational cohort study, individuals who were ≥60 years of age and were registered in the Swedish Fracture Register (SFR) from 2012 to 2018 due to extracapsular fracture and were primarily treated with an IMN or SHS were followed in the SFR and the Swedish Arthroplasty Register (SAR) for a minimum of 1 year. The primary outcome was the cumulative incidence of conversion to arthroplasty (conversion rate). The secondary outcome was the cumulative incidence of all reoperations (reoperation rate). Both were calculated in a competing risk analysis during the first 5 years. RESULTS: We included 19,604 individuals (70% women), with a median age of 85 years (range, 60 to 107 years). The 31-A2 fracture was most prevalent (52%), followed by the 31-A1 fracture (28%). No significant differences were seen in the 1-year conversion rate after IMN or SHS use (1.0% compared with 0.9% in the 31-A1 fractures, 1.7% compared with 1.3% in the 31-A2 fractures, and 1.3% compared with 1.5% in the 31-A3 fractures) or in the 1-year reoperation rate (1.9% compared with 1.9% in the type-A1 fractures, 3.4% compared with 2.5% in the type-A2 fractures, and 4.0% compared with 5.2% in the type-A3 fractures). Only in 31-A2 fractures were more reoperations seen after IMN use at 2 and 5 years (p < 0.05). The crude 1-year-mortality was 26.4% (5,178 of 19,604), without significant differences between implants. CONCLUSIONS: Considering conversion arthroplasty, IMNs and SHSs performed equally well in general. IMN use was associated with more reoperations than SHS use in 31-A2 fractures at 2 years. However, from a clinical perspective, the differences between the implants were small, in particular when considering the competing risk of dying. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

A new bone adhesive candidate- does it work in human bone? An ex-vivo preclinical evaluation in fresh human osteoporotic femoral head bone.

INTRODUCTION: The fixation of small intraarticular bone fragments is clinically challenging and an obvious first orthopaedic indication for an effective bone adhesive. In the present study the feasibility of bonding freshly harvested human trabecular bone with OsSticR, a novel phosphoserine modified cement, was evaluated using a bone cylinder model pull-out test and compared with a commercial fibrin tissue adhesive. METHODS: Femoral heads (n=13) were collected from hip fracture patients undergoing arthroplasty and stored refrigerated overnight in saline medium prior to testing. Cylindrical bone cores with a pre-inserted bone screw, were prepared using a coring tool. Each core was removed and glued back in place with either the bone adhesive (α-tricalcium phosphate, phosphoserine and 20% trisodium citrate solution) or the fibrin glue. All glued bones were stored in bone medium at 37°C. Tensile loading, using a universal testing machine (5 kN load cell), was applied to each core/head. For the bone adhesive, bone cores were tested at 2 (n=13) and 24 (n=11) hours. For the fibrin tissue adhesive control group (n=9), bone cores were tested exclusively at 2 hours. The femoral bone quality was evaluated with micro-CT. RESULTS: The ultimate pull-out load for the bone adhesive at 2 hours ranged from 36 to 171 N (mean 94 N, SD 42 N). At 24 hours the pull-out strength was similar, 47 to 198 N (mean 123 N, SD 43 N). The adhesive failure usually occurred through the adhesive layer, however in two samples, at 167 N and 198 N the screw pulled out of the bone core. The fibrin tissue adhesive group reached a peak force of 8 N maximally at 2 hours (range 2.8-8 N, mean 5.4 N, SD 1.6 N). The mean BV/TV for femoral heads was 0.15 and indicates poor bone quality. CONCLUSION: The bone adhesive successfully glued wet and fatty tissue of osteoporotic human bone cores. The mean ultimate pull-out force of 123 N at 24 hours corresponds to ∼ 300 kPa shear stress acting on the bone core. These first ex-vivo results in human bone are a promising step toward potential clinical application in osteochondral fragment fixation.

The effect of two types of resorbable augmentation materials - a cement and an adhesive - on the screw pullout pullout resistance in human trabecular bone.

Augmentation materials, such as ceramic and polymeric bone cements, have been frequently used to improve the physical engagement of screws inserted into bone. While ceramic, degradable cements may ultimately improve fixation stability, reports regarding their effect on early fixation stability have been inconsistent. On the other hand, a newly developed degradable ceramic adhesive that can bond with tissues surrounding the screw, may improve the pullout performance, ensure early stability, and subsequent bony integration. The aim of this study was to investigate failure mechanisms of screw/trabecular bone constructs by comparing non-augmented screws with screws augmented with a calcium phosphate cement or an adhesive, i.e. a phosphoserine-modified calcium phosphate. Pullout tests were performed on screws inserted into trabecular cylinders extracted from human femoral bone. Continuous and stepwise pullout loading was applied with and without real-time imaging in a synchrotron radiation micro-computed tomograph, respectively. Statistical analysis that took the bone morphology into account confirmed that augmentation with the adhesive supported significantly higher pullout loads compared to cement-augmented, or non-augmented screws. However, the adhesive also allowed for a higher injection volume compared to the cement. In-situ imaging showed cracks in the vicinity of the screw threads in all groups, and detachment of the augmentation materials from the trabecular bone in the augmented specimens. Additional cracks at the periphery of the augmentation and the bone-material interfaces were only observed in the adhesive-augmented specimen, indicating a contribution of surface bonding to the pullout resistance. An adhesive that has potential for bonding with tissues, displayed superior pullout resistance, compared to a brushite cement, and may be a promising material for cementation or augmentation of implants.

Epidemiology, classification, treatment and mortality of distal radius fractures in adults: an observational study of 23,394 fractures from the national Swedish fracture register.

BACKGROUND: Distal radius fractures are the most common of all fractures. Optimal treatment is still debated. Previous studies report substantial changes in treatment trends in recent decades. Few nation-wide studies on distal radius fracture epidemiology and treatment exist, none of which provide detailed data on patient and injury characteristics, fracture pattern and mortality. The aim of this study was to describe the epidemiology, fracture classification, current treatment regimens and mortality of distal radius fractures in adults within the context of a large national register study. METHODS: We performed a descriptive study using prospectively registered data from the Swedish fracture register. Included were all non-pathological distal radius fractures registered between January 1st 2015 and December 31st 2017 in patients aged 18 years and above. Nominal variables were presented as proportions of all registered fractures. RESULTS: A total of 23,394 distal radius fractures in 22,962 patients were identified. The mean age was 62.7 ± 17.6 years for all, 65.4 ± 16.0 for women and 53.6 ± 20.0 for men. A simple fall was the most common cause of injury (75%, n = 17,643/23,394). One third (33%, n = 7783/21,723) of all fractures occurred at the patients' residence. 65% (n = 15,178/23,394) of all fractures were classified as extra-articular AO-23-A, 12% (n = 2770/23,394) as partially intra-articular AO-23-B and 23% (n = 5446/23,394) as intra-articular AO-23-C. The primary treatment was non-surgical for 74% (n = 17,358/23,369) and surgical for 26% (n = 6011/23,369) of all fractures. Only 18% of the AO-23-A fractures were treated surgically, compared to 48% of the AO-23-C fractures. The most frequently used surgical method was plate fixation (82%, n = 4954/5972), followed by pin/wire fixation (8.2%, n = 490/5972), external fixation (4.8%, n = 289/5972) and other methods (4.0%, n = 239/5972). The overall 30-day mortality was 0.4% (n = 98/23,394) and the 1-year mortality 2.9% (n = 679/23,394). CONCLUSION: This nation-wide observational study provides comprehensive data on the epidemiology, fracture classification and current treatment regimens of distal radius fractures in a western European setting. The most common patient was an eldery woman who sustained a distal radius fracture through a simple fall in her own residence, and whose fracture was extra-articluar and treated non-surgically.

Femoral fracture classification in the Swedish Fracture Register - a validity study.

BACKGROUND: A total of more than 270,000 fractures are registered in the Swedish Fracture Register (SFR), a national quality register. Fractures are classified following the AO/OTA classification, commonly by a junior doctor. As a step in the process of validating the data in the SFR, several studies of the accuracy of the fracture classification have already been published. The aim of this study was to evaluate the accuracy of femoral fracture classification in the SFR. METHODS: One hundred and eighteen femur fractures were randomly selected from the SFR. Three experienced orthopaedic surgeons individually classified these fractures on two separate occasions and a gold standard classification was established. This classification was compared with the original classification in the SFR. Inter- and intraobserver agreement was calculated. RESULTS: The agreement between the classification in the SFR and the gold standard classification was kappa = 0.65 for the AO/OTA group and kappa = 0.83 for the AO/OTA type. This corresponds to substantial and almost perfect agreement, according to Landis and Koch. The kappa values for interobserver agreement ranged from 0.64-0.76 for the AO/OTA group and 0.76-0.85 for the AO/OTA type. The kappa values for intraobserver agreement ranged from 0.79-0.81 for the AO/OTA group and 0.91-0.93 for the AO/OTA type. CONCLUSIONS: The classification of femoral fractures in the Swedish Fracture Register is substantial (AO/OTA group) to almost perfect (AO/OTA type) and as accurate as in previous studies. The present study also shows that the agreement between the SFR classification and a gold standard classification is in the same range of agreement as between experienced raters. In contrast to previous studies, the classifications in the SFR are made by an unselected group of mostly inexperienced classifiers. The results indicate that the fracture classification in a national quality register can be accurate enough to permit the evaluation of fracture treatment in specific groups of fractures.

Epidemiology, treatment and mortality of trochanteric and subtrochanteric hip fractures: data from the Swedish fracture register.

BACKGROUND: Hip fractures are a major worldwide public health problem and includes two main types of fractures: the intracapsular (cervical) and the extracapsular (trochanteric and subtrochanteric) fractures. The aim of this study on patients with trochanteric and subtrochanteric hip fractures was to describe the epidemiology, treatment and outcome in terms of mortality within the context of a large register study. METHODS: A descriptive epidemiological register study including patients registered in the national Swedish Fracture Register from January 2014 to December 2016. Inclusion criteria were all primary surgically treated traumatic non-pathological trochanteric and subtrochanteric femoral fractures in patients aged 18 years and above. Individual patient data (age, gender, injury location, injury cause, fracture type, treatment and timing of surgery) were retrieved from the register database. Mortality data was obtained via linkage to the Swedish Death Register. RESULTS: A total of 10,548 consecutive patients were identified and included in the study. The mean (±SD) age for all patients was 82 ± 11 years and the majority of the patients were females (69%). Most of the fractures were caused by a fall at the same level (83%) at the patients' accommodation (75%). Fractures were classified using the AO/OTA classification as 31-A1 in 29%, as 31-A2 in 49% and as 31-A3 in 22% of the cases. The most commonly used implant was a short antegrade intramedullary nail (42%), followed by a plate with sliding hip screw (37%). With increasing fracture complexity, the proportion of intramedullary nails was increasing, and also the use of long versus short nails. The majority of the patients were operated within 36 h (90%). There was a higher mortality at 30 days and 1 year for males, and for all those who were delayed to surgery > 36 h. CONCLUSION: Safety measures to prevent fall at elderly patient's accommodation might be a way to reduce the number of trochanteric and subtrochanteric hip fractures. Surgery as soon as possible without delay should be considered to reduce the mortality rate. The selection of surgical methods depends on the fracture complexity.

Trochanteric fracture-implant motion during healing - A radiostereometry (RSA) study.

Cut-out complication remains a major unsolved problem in the treatment of trochanteric hip fractures. A better understanding of the three-dimensional fracture-implant motions is needed to enable further development of clinical strategies and countermeasures. The aim of this clinical study was to characterise and quantify three-dimensional motions between the implant and the bone and between the lag screw and nail of the Gamma nail. Radiostereometry Analysis (RSA) analysis was applied in 20 patients with trochanteric hip fractures treated with an intramedullary nail. The following three-dimensional motions were measured postoperatively, at 1 week, 3, 6 and 12 months: translations of the tip of the lag screw in the femoral head, motions of the lag screw in the nail, femoral head motions relative to the nail and nail movements in the femoral shaft. Cranial migration of the tip of the lag screw dominated over the other two translation components in the femoral head. In all fractures the lag screw slid laterally in the nail and the femoral head moved both laterally and inferiorly towards the nail. All femoral heads translated posteriorly relative to the nail, and rotations occurred in both directions with median values close to zero. The nail tended to retrovert in the femoral shaft. Adverse fracture-implant motions were detected in stable trochanteric hip fractures treated with intramedullary nails with high resolution. Therefore, RSA method can be used to evaluate new implant designs and clinical strategies, which aim to reduce cut-out complications. Future RSA studies should aim at more unstable fractures as these are more likely to fail with cut-out.

Three-dimensional bone-implant movements in trochanteric hip fractures: Precision and accuracy of radiostereometric analysis in a phantom model.

The accuracy and precision of RSA were evaluated in the experimental study of screw cut-out complication after fixation of trochanteric fractures. A plastic bone model of a two-part trochanteric fracture was constructed with a Gamma nail implant incorporating RSA markers. The femoral head fragment was attached to a separate rotational table and the femoral shaft was mounted on the micrometer. Three main motions were simulated: Femoral head translation and rotation along the axis of the lag screw and fracture fragment translation along anatomical axes. Accuracy and precision were determined according to ISO 16,087 and ASTM standard F2385-04. Translations along the lag screw axis were measured with a precision within ±0.14 mm and an accuracy within ±0.03 mm. With simultaneous translations along all three anatomical axes, lowest precision was measured for the x-axis (±0.29, 0.07 mm, respectively), but improved when analyzed as a vector (±0.08, 0.03 mm). The precision and accuracy of femoral head rotations were within 0.5° and 0.18°, respectively. The resolution of the RSA method tested in this model was high, though it varied depending on the type of analyzed motion. This information is valuable when selecting and interpreting outcome parameters evaluating implant migration and osteosynthesis stability in future clinical RSA studies.

Critical factors in cut-out complication after Gamma Nail treatment of proximal femoral fractures.

BACKGROUND: The most common mechanical failure in the internal fixation of trochanteric hip fractures is the cut-out of the sliding screw through the femoral head. Several factors that influence this complication have been suggested, but there is no consensus as to the relative importance of each factor. The purpose of this study was to analyse the cut-out complication with respect to the following variables: patients' age, fracture type, fracture reduction, implant positioning and implant design. METHODS: 3066 consecutive patients were treated for trochanteric fractures with Gamma Nails between 1990 and 2002 at the Centre de Traumatologie et de l'Orthopedie (CTO), Strasbourg, France. Cut-out complications were identified by reviewing all available case notes and radiographs. Subsequently, the data were analysed by a single reviewer (AJB) with focus on the studied factors. RESULTS: Seventy-one cut-out complications were found (2.3%) of the 3066 trochanteric fractures. Cut-out failure associated with avascular head necrosis, pathologic fracture, deep infection or secondary to prior failure of other implants were excluded from the study (14 cases). The remaining 57 cases (1.85%, median age 82.6, 79% females) were believed to have a biomechanical explanation for the cut-out failure. 41 patients had a basicervical or complex fracture type. A majority of cut-outs (43 hips, 75%) had a combination of the critical factors studied; non-anatomical reduction, non-optimal lag screw position and the characteristic fracture pattern found. CONCLUSIONS: The primary cut-out rate of 1.85% was low compared with the literature. A typical cut-out complication in our study is represented by an unstable fracture involving the trochanteric and cervical regions or the combination of both, non-anatomical reduction and non-optimal screw position. Surgeons confronted with proximal femoral fractures should carefully scrutinize preoperative radiographs to assess the primary fracture geometry and fracture classification. To reduce the risk of a cut-out it is important to achieve both anatomical reduction and optimal lag screw position as these are the only two factors that can be controlled by the surgeon.

3066 consecutive Gamma Nails. 12 years experience at a single centre.

BACKGROUND: Fixation of trochanteric hip fractures using the Gamma Nail has been performed since 1988 and is today well established and wide-spread. However, a number of reports have raised serious concerns about the implant's complication rate. The main focus has been the increased risk of a subsequent femoral shaft fracture and some authors have argued against its use despite other obvious advantages, when this implant is employed. Through access to a uniquely large patient data base available, which is available for analysis of trochanteric fractures; we have been able to evaluate the performance of the Gamma Nail over a twelve year period. METHODS: 3066 consecutive patients were treated for trochanteric fractures using Gamma Nails between 1990 and 2002 at the Centre de Traumatologie et de l'Orthopedie (CTO), Strasbourg, France. These patients were retrospectively analysed. Information on epidemiological data, intra- and postoperative complications and patients' outcome was retrieved from patient notes. All available radiographs were assessed by a single reviewer (AJB). RESULTS: The results showed a low complication rate with the use of the Gamma Nail. There were 137 (4.5%) intraoperative fracture-related complications. Moreover 189 (6.2%) complications were detected postoperatively and during follow-up. Cut-out of the lag screw from the femoral head was the most frequent mechanical complication (57 patients, 1.85%), whereas a postoperative femoral shaft fracture occurred in 19 patients (0.6%). Other complications, such as infection, delayed healing/non-union, avascular femoral head necrosis and distal locking problems occurred in 113 patients (3.7%). CONCLUSIONS: The use of the Gamma Nail in trochanteric hip fractures is a safe method with a low complication rate. In particular, a low rate of femoral shaft fractures was reported. The low complication rate reported in this series can probably be explained by strict adherence to a proper surgical technique.