Cross-Table Lateral Radiographs Accurately Predict Displacement in Valgus-Impacted Femoral Neck Fractures.

BACKGROUND: Femoral neck fractures are classified as nondisplaced (Garden types I and II) or displaced (Garden types III and IV) on the basis of anteroposterior radiographs. Cross-table lateral radiographs are important in the assessment of Garden type-I and II fractures as posterior tilt of the femoral head may influence treatment results. A posterior tilt of >20° has been associated with an increased risk of treatment failure after internal fixation, although the precision of these measurements has not been validated. Therefore, the purpose of the present study was to compare cross-table lateral radiographs with 3-dimensional computed tomographic (3D-CT) reconstructions of Garden type-I and II femoral neck fractures. METHODS: Twenty-three patients presenting with Garden type-I and II femoral neck fractures that were verified on anteroposterior radiographs underwent CT scanning immediately after radiographic examination. 3D models of the fractured and uninjured femora were reconstructed from the CT images, and displacement of the 3D models was determined by superimposing the fractured and uninjured femora. We defined a coordinate system with its origin at the center of the uninjured femoral head with the x axis oriented medially; the y axis, posteriorly; and the z axis, cranially. Correlations between lateral radiographs and 3D models were assessed with the Spearman rank coefficient, mean difference, and limits of agreement. RESULTS: Posterior tilt of the femoral head on lateral radiographs was strongly correlated with displacement of the femoral head along the y axis of the 3D models, with a correlation coefficient of 0.86 (p < 0.001). Correlations between the findings on lateral radiographs and displacements along the x or z axis were weak, with coefficients of -0.30 (p = 0.18) and 0.21 (p = 0.34), respectively. The mean difference between displacement on lateral radiographs and displacement along the y axis of the 3D models was smaller, and demonstrated a smaller limits-of-agreement interval, compared with the x or z axis. CONCLUSIONS: Our results demonstrated a strong correlation between posterior displacement of the femoral head on lateral radiographs and displacement along the y axis in 3D models of Garden type-I and II femoral neck fractures. This finding indicates that lateral radiographs provide an accurate assessment of posterior tilt.

Screw Fixation Versus Hemiarthroplasty for Nondisplaced Femoral Neck Fractures in Elderly Patients: A Multicenter Randomized Controlled Trial.

BACKGROUND: Elderly patients with a displaced femoral neck fracture treated with hip arthroplasty may have better function than those treated with internal fixation. We hypothesized that hemiarthroplasty would be superior to screw fixation with regard to hip function, mobility, pain, quality of life, and the risk of a reoperation in elderly patients with a nondisplaced femoral neck fracture. METHODS: In a multicenter randomized controlled trial (RCT), Norwegian patients ≥70 years of age with a nondisplaced (valgus impacted or truly nondisplaced) femoral neck fracture were allocated to screw fixation or hemiarthroplasty. Assessors blinded to the type of treatment evaluated hip function with the Harris hip score (HHS) as the primary outcome as well as on the basis of mobility assessed with the timed "Up & Go" (TUG) test, pain as assessed on a numerical rating scale, and quality of life as assessed with the EuroQol-5 Dimension-3 Level (EQ-5D) at 3, 12, and 24 months postsurgery. Results, including reoperations, were assessed with intention-to-treat analysis. RESULTS: Between February 6, 2012, and February 6, 2015, 111 patients were allocated to screw fixation and 108, to hemiarthroplasty. At the time of follow-up, there was no significant difference in hip function between the screw fixation and hemiarthroplasty groups, with a 24-month HHS (and standard deviation) of 74 ± 19 and 76 ± 17, respectively, and an adjusted mean difference of -2 (95% confidence interval [CI] = -6 to 3; p = 0.499). Patients allocated to hemiarthroplasty were more mobile than those allocated to screw fixation (24-month TUG = 16.6 ± 9.5 versus 20.4 ± 12.8 seconds; adjusted mean difference = 6.2 seconds [95% CI = 1.9 to 10.5 seconds]; p = 0.004). Furthermore, screw fixation was a risk factor for a major reoperation, which was performed in 20% (22) of 110 patients who underwent screw fixation versus 5% (5) of 108 who underwent hemiarthroplasty (relative risk reduction [RRR] = 3.3 [95% CI = 0.7 to 10.0]; number needed to harm [NNH] = 6.5; p = 0.002). The 24-month mortality rate was 36% (40 of 111) for patients allocated to internal fixation and 26% (28 of 108) for those allocated to hemiarthroplasty (RRR = 0.4 [95% CI = -0.1 to 1.1]; p = 0.11). Two patients were lost to follow-up. CONCLUSIONS: In this multicenter RCT, hemiarthroplasty was not found to be superior to screw fixation in reestablishing hip function as measured by the HHS (the primary outcome). However, hemiarthroplasty led to improved mobility and fewer major reoperations. The findings suggest that certain elderly patients with a nondisplaced femoral neck fracture may benefit from being treated with a latest-generation hemiarthroplasty rather than screw fixation. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Bilateral symmetrical comparison of the proximal femur using 3D-CT models.

PURPOSE: Superimposed three-dimensional (3D)-models obtained from CT-images have been used to evaluate displacement of femoral neck fractures, but this method assumes symmetrical anatomy of normal femurs. The present study aimed to compare the spatial orientation of the left and right proximal femur, thus establishing if 3D models can be used as a reference standard for the evaluation of fracture displacement. METHODS: We generated 3D-CT-models of 20 patients with no skeletal pathology of the proximal femurs. Three observers independently determined the positions of the fovea and the femoral head, and a vector intersecting the centre points of the fovea and the femoral head defined the rotation. Differences in positions and rotations were determined by superimposing the 3D-CT-models of both femurs. RESULTS: The mean distance (95% CI) between positions of the left and right fovea was 3.1 mm (2.7-3.4) and between the left and right femoral head 2.8 mm (2.6-3.0). The minimal detectable change was 2.8 for the fovea and 2.3 for the femoral head, and the repeatability coefficients between 2.1-2.7 and 1.0-2.9, respectively. Mean difference in rotation of the femoral head was 6° (5.3-6.6) with a minimal detectable change of 8.8 and repeatability coefficients ranging from 5.8 to 10.0. CONCLUSIONS: Distances between the left and right femoral heads were larger than what could be explained by measurement error alone, suggesting that there may be minor side-to-side differences. However, these differences are small, and 3D-CT-models can be used as a reference standard to evaluate displacement of femoral neck fractures.

Validity and reliability of the Norwegian translation of the Achilles tendon Total Rupture Score.

PURPOSE: Patient reported outcome measures (PROMs) are increasingly being used in clinical research. The Achilles tendon Total Rupture Score (ATRS) is a PROM designed to assess outcomes in patients with ruptures of the Achilles tendon. The aim of this study was to develop a Norwegian adaption of the ATRS and evaluate its validity and reliability. METHODS: The ATRS was translated into Norwegian in accordance with recommended guidelines. The study included 94 patients treated for Achilles tendon ruptures from January 2010 until February 2013, and the web-based questionnaires were administered twice. Reliability was assessed by Cronbach's alpha, the intraclass correlation coefficient (ICC) and minimal detectable change (MDC). Construct validity was evaluated by calculating the Spearman's correlation coefficient with the five subclasses of the Foot and Ankle Outcome Score (FAOS), the SF-36 subclass physical function and the SF-36 physical and mental summary scores. RESULTS: Both internal consistency (Cronbach's alpha = 0.96) and test-retest reliability (ICC = 0.90) were excellent, and the MDC was 2.12 at the group level and 16.98 at the individual level. Construct validity was supported by Spearman's correlation coefficients above 0.7 with the SF-36 subclass physical function and the SF-36 physical summary score as well as the FAOS subclasses Sport/Rec and quality of life. There was no floor effect, and 6 patients (6.4%) achieved a maximum score of 100. CONCLUSIONS: The Norwegian adaption of the ATRS demonstrates acceptable validity and reliability for use in the Norwegian population to assess clinical outcomes in patients with Achilles tendon ruptures.

Ultrasound measurements of Achilles tendon length using skin markings are more reliable than extended-field-of-view imaging.

PURPOSE: Elongation of the Achilles tendon has been associated with poorer function in patients treated for ruptures. This has led to the development of various ultrasound-based measurements, and the purpose of the present study was to compare the reliability of three ultrasound-based measuring procedures. METHODS: Twenty healthy individuals (40 tendons) were assessed by two testers at two occasions, 12 weeks apart. The tendon length was measured from the calcaneal insertion to the mid-sagittal muscle tendon junction (MTJ) using skin markings or extended-field-of-view (EFOV) imaging, or from the calcaneal insertion to the distal medial MTJ using skin markings. Test-retest and inter-tester reliability as well as side-to-side length differences were assessed for all three procedures. RESULTS: Test-retest intraclass correlation coefficients (ICCs) for measurements from the mid-sagittal MTJ using EFOV imaging and skin markings, and from the distal medial MTJ using skin markings were 0.83, 0.90 and 0.96 for tester 1 and 0.87, 0.91 and 0.96 for tester 2, respectively. The corresponding inter-tester ICCs were 0.85, 0.91 and 0.96. Side-to-side lengths were significantly different for measurements from the mid-sagittal MTJ and the distal medial MTJ using skin markings, with mean differences of 0.3 and 0.4 cm, respectively. CONCLUSIONS: Test-retest and inter-tester ICCs were excellent for all three measuring procedures, however, the use of skin markings provided consistently better agreement and reliability compared to EFOV images. The best agreement and highest ICCs were achieved for measurements from the distal medial MTJ, but side-to-side length differences warrant caution when contralateral measurements are used to evaluate tendon elongation. LEVEL OF EVIDENCE: III.

Eight orthopedic surgeons achieved moderate to excellent reliability measuring the preoperative posterior tilt angle in 50 Garden-I and Garden-II femoral neck fractures.

BACKGROUND: Studies of elderly patients with Garden-I and Garden-II femoral neck fractures (FNFs) suggest that a preoperative posterior tilt of the femoral head of at least 20° increases the risk of fixation failure. A recently published treatment algorithm recommended hemiarthroplasty over internal fixation for elderly patients with Garden-I and Garden-II FNFs and a preoperative posterior tilt of at least 20°. However, the reliability of the method used to measure the posterior tilt has not been assessed according to recommended standards for reliability trials. METHODS: Four orthopedic registrars and four consultants measured the posterior tilt angle in 50 preoperative lateral radiographs at two occasions six weeks apart. We estimated inter- and intrarater reliability by intraclass correlation coefficient (ICC). We also assessed repeatability by the repeatability coefficient (RC) and agreement by the minimal detectable change (MDC). Based on the suggested cutoff value of 20°, we reported the overall percentage and specific agreement for the choice of implant. RESULTS: Inter- and intrarater reliability for all raters was excellent with an ICC (95% CI) of 0.77 (0.69-0.85) and 0.77 (0.67-0.86), respectively. The RC was 13.9 and the MDC 14.1. Specific agreement for choosing arthroplasty was 61.3 and 54.6% for the first and second test occasion, respectively. CONCLUSIONS: Eight orthopedic surgeons measured the posterior tilt in 50 Garden-I and Garden-II FNFs and achieved excellent inter- and intrarater reliability. However, variations in repeated measurements and variations in measurements made by different raters, as assessed by the RC and the MDC respectively, ranged from 13.9° to 14.1°. The variations in posterior tilt measurements should be taken into account when choosing the type of implant for elderly patients with Garden-I and Garden-II femoral neck fractures.

The influence of the hips position on measurements of posterior tilt in a valgus-impacted femoral neck fracture.

INTRODUCTION: Lateral radiographs are important for the evaluation of Garden I and II femoral neck fractures. These fractures appear undisplaced in the anteroposterior view, but posterior tilt of the femoral head may still be present in the lateral view. The influence of posterior tilt is, however, debated, which could be caused by the use of non-standardized cross-table radiographs in the conflicting reports. The aim of this bone-model study was therefore to evaluate the influence of the hips position on measurements of posterior tilt. MATERIALS AND METHODS: We generated models of a Garden I-II femoral neck fracture and the non-injured contralateral femur from CT reconstructions with a 3D-printer. Lateral radiographs of the models were obtained in positions ranging from 90° internal rotation (IR) to 90° external rotation (ER) and 0-80° flexion. Two investigators independently measured posterior tilt on 27 lateral radiographs obtained from each model. RESULTS: The inter-tester ICC was 0.91 (0.84-0.94), standard error of measurement (SEM) 2.6, and minimal detectable change (MDC) 7.2. The median (range) posterior tilt for the fracture model was 21.9° (5.0, 33.8) and 23.6° (2.2, 28.6) for observer 1 and observer 2, respectively. The corresponding posterior tilt within the range of 10° IR to 40° ER and 0 to 30° flexion of the fracture model, was 27.3° (24.0, 33.8) and 26.3° (24.8, 28.6). DISCUSSION: The range of posterior tilt measurements for positions of the proximal femur restricted from 10° IR to 40° ER and 0 to 30° flexion, was above the MDC for observer 1, and below the MDC for observer 2. These findings indicate that rotation and flexion affect measurements of posterior tilt, but the influence may be negligible for positions of the injured extremity that are clinically relevant during cross-table lateral radiographs. A larger study that accounts for variations in anatomy and fracture displacement is required to confirm these findings.

Preoperative posterior tilt of at least 20° increased the risk of fixation failure in Garden-I and -II femoral neck fractures.

Background and purpose - It has been suggested that preoperative posterior tilt of the femoral head may increase the risk of fixation failure in Garden-I and -II femoral neck fractures. To investigate this association, we studied a cohort of 322 such patients. Patients and methods - Patients treated with internal fixation between 2005 and 2012 were retrospectively identified using hospital records and the digital image bank. 2 raters measured the preoperative posterior tilt angle and categorized it into 3 groups: < 10°, 10-20°, and ≥ 20°. The inter-rater reliability (IRR) was determined. Patients were observed until September 2013 (with a minimum follow-up of 18 months) or until failure of fixation necessitating salvage arthroplasty. The risk of fixation failure was assessed using competing-risk regression analysis, adjusting for time to surgery. Results - Patients with a posterior tilt of ≥ 20° had a higher risk of fixation failure: 19% (8/43) as compared to 11% (14/127) in the 10-20° category and 6% (9/152) in the < 10° category (p = 0.03). Posterior tilt of ≥ 20° increased the risk of fixation failure, with an adjusted hazard ratio of 3.4 (95% CI: 1.3-8.9; p = 0.01). The interclass correlation coefficient for angular measurements of posterior tilt was 0.90 (95% CI: 0.87-0.92), and the IRR for the categorization of posterior tilt into 3 groups was 0.76 (95% CI: 0.69-0.81). Interpretation - Preoperative posterior tilt of ≥ 20° in Garden-I and -II femoral neck fractures increased the risk of fixation failure necessitating salvage arthroplasty. The reliability of the methods that we used to measure posterior tilt ranged from good to excellent.

Nonoperative treatment of the medial malleolus in bimalleolar and trimalleolar ankle fractures: a randomized controlled trial.

OBJECTIVES: To compare internal fixation with no fixation of the medial malleolus after open reduction and internal fixation of the lateral malleolus and if needed, the posterior malleolus. DESIGN: Randomized prospective trial. SETTING: Level III trauma center in a metropolitan area. PATIENTS: One hundred patients with bimalleolar or trimalleolar Orthopaedic Trauma Association type 44 ankle fractures and displacement of the medial malleolus less than 2 mm after open reduction and internal fixation of the lateral component. INTERVENTION: Internal fixation or nonoperative treatment of the medial malleolus. MAIN OUTCOME MEASUREMENTS: American Orthopaedic Foot and Ankle Society ankle hind foot score (AOFAS), The Olerud Molander Ankle (OMA) score, and visual analogue pain scale (VAS). RESULTS: Median follow-up time was 39 months (range: 24-72). There were no significant differences between the 2 groups with respect to OMA (P = 0.91), AOFAS (P = 0.85), VAS (P = 0.85), or development of osteoarthritis (P = 0.22). Reoperation and complication rates were also comparable, but 4 patients treated nonoperatively developed nonunion of the medial malleolus. These patients reported no functional disabilities and presented OMA, AOFAS, and VAS scores better than average. CONCLUSIONS: Our data indicate that nonoperative treatment of minimally displaced fractures of the medial malleolus after operative fixation of the fibula yields satisfactory results. However, long-term follow-up is needed due to increased risk of nonunion and uncertainty regarding the development of posttraumatic arthritis. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Failed internal fixation of femoral neck fractures.

BACKGROUND: There are two types of surgical treatment for fractures of the femoral neck; internal fixation and arthroplasty. Internal fixation is associated with a higher risk of complications such as secondary displacement, non-union and avascular necrosis. To improve treatment results of internal fixation, we have tried to identify procedure related risk-factors associated with fixation failure. MATERIAL AND METHOD: A retrospective study was conducted based on the medical records and X-ray images of 337 patients sustaining intracapsular fractures of the hip during the period 1999-2000. The patients were treated with closed reduction and internal fixation at Oslo University Hospital, Aker. The reduction of the fracture and the placement of the fixation implants were evaluated and scored (six points representing best achievable result). RESULTS: Fixation failed in 23 (18,3 %) out of 126 patients with displaced fractures awarded six points for the reduction. In contrast, fixation failed in five (50 %) out of ten patients given a score of three points or less (p = 0.017). The risk of non-union increased when patients were treated more than 48 hours after the initial injury. In this group, 5 (25 %) out of 20 patients developed non-union compared to 16 (8 %) out of 200 patients treated within 48 hours (p = 0.014). INTERPRETATION: Our findings emphasize the importance of achieving anatomical reduction of displaced femoral neck fractures, and to perform surgery within 48 hours unless an acute medical condition needs to be stabilized.

Molecular cloning of LILRC1 and LILRC2 in the mouse and the rat, two novel immunoglobulin-like receptors encoded by the leukocyte receptor gene complex.

We report the molecular cloning of two novel single-member receptor families with homology to LILR/CD85, PIR, and gp49: LILRC1 in the rat and the mouse, and LILRC2 in the rat. LILRC1 and LILRC2 both have two extracellular Ig-like domains and a cytoplasmic tail devoid of any known signaling motifs. The transmembrane regions of LILRC1 and LILRC2 contain an arginine residue, a common feature in receptors that associate with activating adaptor proteins. Rat and mouse LILRC1 are orthologs sharing 81.5% amino acid identity. LILRC2 represents a distinct receptor family, 47.9% identical to LILRC1. No murine LILRC2 ortholog was detected in genome or expressed sequence tag sequence databases. By radiation hybrid mapping, the rat Lilrc1 and Lilrc2 loci were localized to the leukocyte receptor gene complex (LRC) on chromosome 1, and the mouse Lilrc1 locus was mapped to the LRC on chromosome 7. Moreover, the mouse and rat Lilrc1 loci were localized to similar positions within the LRC. As shown by RT-PCR, rat LILRC1 was expressed by B cells, neutrophils, and a macrophage cell line. Transcription of LILRC2 was detected in T cells, B cells, neutrophils, and macrophages.