Interdisciplinary consensus of virtual monochromatic dual-energy CT images: is there discrepancy in preferred photon energy between surgeons and radiologists for the assessment of non-unions?

AIM: To investigate possible differences between surgeons and radiologists in selecting optimal photon energy settings from a set of virtual monochromatic dual-energy computed tomography (CT) images for the assessment of bone union in patients with a suspected non-union of the appendicular skeleton. MATERIALS AND METHODS: Fifty patients suspected of having bone non-union after operative fracture treatment with a variety of fixation implants were included. Patients were scanned on a dual-source CT machine using 150/100-kVp. Monochromatic images were extracted at 70, 90, 110, 130, 150, and 190 keV. Images were reviewed by 159 orthopaedic trauma surgeons and 12 musculoskeletal radiologists in order to select the best and worst energy setting to assess bone union. Furthermore, a confidence score (1-4) was given in selecting the best and worst setting to assess bone union. RESULTS: Monochromatic 190 keV images were selected most frequently as the optimal energy in titanium (34.8%), stainless steel (40%), and combined implants of stainless steel and titanium (40.5%). Confidence scores and average optimal energies were higher and average worst energies were lower for radiologists compared to surgeons in all hardware (p<0.05). Differences in optimal energy were not statistically significant for different alloys or type of fixation implant in both groups. CONCLUSIONS: In both observer groups, 190 keV images were selected most frequently as the optimal energy to assess bone union in patients with a suspected non-union of the appendicular skeleton with hardware in situ. On average, musculoskeletal radiologists selected higher optimal and lower worst energy settings and were more confident in selecting both energy settings than orthopaedic trauma surgeons.

Correction to: Three­dimensional topography of scapular nutrient foramina.

Correction to: Surgical and Radiologic Anatomy.

Three-dimensional topography of scapular nutrient foramina.

PURPOSE: The aim of this study is to describe the number and location of the nutrient foramina in human scapulae which can minimize blood loss during surgery. METHODS: 30 cadaveric scapulae were macerated to denude the skeletal tissue. The nutrient foramina of 0.51 mm and larger were identified and labeled by adhering glass beads. CT scans of these scapulae were segmented resulting in a surface model of each scapula and the location of the labeled nutrient foramina. All scapulae were scaled to the same size projecting the nutrient foramina onto one representative scapular model. RESULTS: Average number of nutrient foramina per scapula was 5.3 (0-10). The most common location was in the supraspinous fossa (29.7%). On the costal surface of the scapula, most nutrient foramina were found directly inferior to the suprascapular notch. On the posterior surface, the nutrient foramina were identified under the spine of the scapula in a somewhat similar fashion as those on the costal surface. Nutrient foramina were least present in the peri-glenoid area. CONCLUSION: Ninety percent of scapulae have more than one nutrient foramen. They are located in specific areas, on both the posterior and costal surface.

The "coracoid tunnel view": a simulation study for finding the optimal screw trajectory in coracoid base fracture fixation.

PURPOSE: Coracoid fractures represent approximately 3-13% of all scapular fractures. Open reduction and internal fixation can be indicated for a coracoid base fracture. This procedure is challenging due to the nature of visualization of the coracoid with fluoroscopy. The aim of this study was to develop a fluoroscopic imaging protocol, which helps surgeons in finding the optimal insertion point and screw orientation for fixations of coracoid base fractures, and to assess its feasibility in a simulation study. METHODS: A novel imaging protocol was defined for screw fixation of coracoid base fractures under fluoroscopic guidance. The method is based on finding the optimal view for screw insertion perpendicular to the viewing plane. In a fluoroscopy simulation environment, eight orthopaedic surgeons were invited to place a screw down the coracoid stalk through the coracoid base and into the neck of 14 cadaveric scapulae using anatomical landmarks. The surgeons placed screws before and after they received an e-learning of the optimal view. Results of the two sessions were compared and inter-rater reliability was calculated. RESULTS: Screw placement was correct in 33 out of 56 (58.9%) before, and increased to 50 out of 56 (89.3%) after the coracoid tunnel view was explained to the surgeons, which was a significant improvement (p < 0.001). CONCLUSIONS: Our newly developed fluoroscopic view based on simple landmarks is a useful addendum in the orthopaedic surgeon's tool box to fixate fractures of the coracoid base.

Surgical accuracy in identifying the elbow rotation axis on fluoroscopic images.

PURPOSE: To assess the accuracy of surgeons in identifying elbow rotation axis (RA) on fluoroscopic images and to measure the interobserver variability. METHODS: Five healthy subjects underwent 3-dimensional computed tomography (CT) analysis of their nondominant elbow. Real-time rotation software enabled surgeons to approximate the elbow RA on CT-reconstructed fluoroscopy, which was repeated twice with different starting positions to increase the number of observations. The surgeons used anatomical landmarks of choice. Analysis of variance (ANOVA) was used to determine structural error differences between surgeons, and intraclass correlation coefficients (ICCs) were used to determine the corresponding interobserver variability. RESULTS: Eight subspecialty-trained trauma surgeons (P.K., N.W.L.S., V.M.d.J., P.J., G.M.K., R.W.P., T.S., B.A.v.D.) participated and attempted to identify the RA on reconstructed fluoroscopy. A total of 15 RA definitions on 5 elbows were recorded per surgeon. The surgeons had a mean rotational error of 5° (range, < 1°-13°) and mean translational error of 1 mm (range, < 1-8 mm), compared with the true elbow RA as measured by the 3-dimensional CT analysis. The ANOVA showed structural differences between surgeons in rotational and translational errors, indicating that some surgeons consistently had more accurately identified the elbow RA than others. The ICC was 0.12 for rotational error and 0.10 for translational error, indicating a large interobserver variability. CONCLUSIONS: We show in this in vivo study that identification of the elbow RA on fluoroscopy is associated with substantial rotational errors and large inconsistencies among surgeons. Implementation of standardized anatomical landmarks is required to improve surgeons' accuracy. These landmarks should preferably take into account both the coronal and the sagittal planes, using the orientation of the capitellum and trochlea as well as the posterior distal humeral cortex. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

Bacterial reservoir in deeper skin is a potential source for surgical site and biomaterial-associated infections.

BACKGROUND: The origin of surgical site and biomaterial-associated infection is still elusive. Micro-organisms contaminating the wound may come from the air in the operating theatre, the surgical team or the skin of the patient. The skin of patients is disinfected prior to surgery, but bacteria deeper in the skin (e.g. in sweat glands or sebaceous glands) may not be reached. METHODS: A preliminary cohort study was performed to study the origin of surgical site and biomaterial-associated infection between May 2020 and February 2021. In order to investigate whether cutaneous microbiota colonize the wound when released from the skin upon cutting, aerobic and anaerobic bacteria were isolated, quantified and identified from the skin of 99 patients undergoing trauma surgery, before and after skin disinfection, from knife blades and from the wound directly after the first cut. RESULTS: Ninety-nine percent of the patients were culture-positive before disinfection with chlorhexidine. Of these, 40% were still culture-positive after disinfection. Of these, 54% had a positive culture of the wound after cutting the skin. Twenty percent of the patients with a negative culture after disinfection had a positive wound culture after cutting the skin. Staphylococcus epidermidis and Cutibacterium acnes were the most commonly cultured bacterial species. In 9% of cases, more than 100 bacterial colonies were cultured from the wound; this may cause biomaterial-associated infection. CONCLUSION: Bacteria residing in the skin and not eradicated by disinfection may enter the surgical wound upon cutting, resulting in contamination which may cause biomaterial-associated infection.

Pelvic stress fracture in a Dutch U19 cricketer: a case report.

We report a case of a non-traumatic right-sided os ischium fracture and ramus inferior fracture in an 18-year-old cricket athlete of the national Dutch team. Occasionally, apophyseal avulsion fractures of the pelvis occur; however, non-traumatic isolated fractures of the os ischium are rare. This case highlights the treatment and result of an unusual cricket injury.

Locking plate constructs in subtrochanteric fixation: a biomechanical comparison of LCP screws and AO-nuts.

OBJECTIVES: Various studies have reported the use of the 95-degree condylar blade plate in the treatment of a subtrochanteric fracture or non-union. However, the holding power of standard screws in the metaphyseal and diaphyseal area is often diminished due to osteopenia. The alternative in this area is the use of locking plates, Schühlis or AO-nuts. With the latter two, non-locking screws in the blade plate can be converted to a fixed angle fixation. The objective of this study was to compare the stiffness and strength of the AO-nut augmented 95-degree condylar blade plate construct with that of a locking plate construct. In addition, a clinical series of eight patients treated with the AO-nut augmented 95-degree condylar blade plate construct is presented. METHODS: Single screw-plate constructs of a 5.0 mm locking screw/locking compression plate (LCP) and a 4.5 mm non-locking screw/4.5 mm dynamic compression plate (DCP), converted to a fixed-angle screw construct using AO-nuts, were tested by cantilever bending. During loading, force and displacement were recorded, from which the bending stiffness (N/mm) and the yield strength (N) were determined. Secondarily, all patients that underwent surgical treatment for subtrochanteric fracture, malunion or non-union by the senior author using this technique, underwent chart review. RESULTS: The stiffness of the locking screws was about four times higher compared to the AO-nut augmented construct. The yield strength was 2.3 times higher for the locking screw construct. In none of the eight patients treated with the fixed-angle blade plate, failure of the AO-nut augmented construct occurred. CONCLUSIONS: Although the stiffness and strength of the AO-nut augmented construct is less than of the locking screw, excellent clinical outcomes can be achieved utilizing this construct.

Treatment of midshaft clavicular delayed and non-unions with anteroinferior locking compression plating.

INTRODUCTION: Pain and impaired shoulder function are the predominant symptoms of midshaft clavicle non-unions. Obtaining consolidation and improvement of shoulder function is often successfully achieved with osteosynthesis and bone grafting. Most data in the literature pertain to plate osteosynthesis, placing the plate on the subcutaneous superior aspect of the clavicle. Although union rates are generally high, most patients require hardware removal as the plate is prominent under the skin causing pain and cosmetic problems. MATERIALS AND METHODS: In the current retrospective study, we followed a cohort of 21 consecutive cases (20 patients) with a midshaft clavicular delayed or non-union, treated with anteroinferior plating using a 3.5 mm locking compression plate (LCP) for a mean of 30 months. RESULTS: We operated on 10 males and 10 females with a mean age of 48.2 years (range 16-65). There was one early plate failure that needed revision. Two patients required hardware removal because of prominence of the plate. All but two patients were satisfied with the final cosmetic result. The average DASH score at follow up was 22.8. DISCUSSION AND CONCLUSIONS: Anteroinferior plating with a 3.5 mm LCP is a reliable and reproducible treatment of midshaft clavicular delayed and non-union regarding consolidation, function, cosmesis and reduction of second surgery.

Improved diagnostic confidence in evaluating bone non-union using virtual monochromatic dual-energy CT.

PURPOSE: The aim of this study was to determine whether virtual monochromatic dual-energy CT imaging improves the evaluation of suspected non-union of the appendicular skeleton treated with titanium or stainless steel intramedullary nails and plates. METHOD: Forty-one patients with a clinical suspected non-union with hardware in place were included and scanned on a dual-source CT-scanner using 100/Sn150kVp. Images including titanium hardware were extracted at 130 keV. Images including stainless steel hardware were extracted at 150 keV. Monochromatic 70 keV images served as reference. Non-union confirmed during revision surgery was used as gold standard. A musculoskeletal radiologist and orthopedic trauma surgeon evaluated images on image quality, degree and location of consolidation, non-union type and diagnostic confidence. RESULTS: Likert scores with respect to image quality improved from 0.88 to 1.83 (p < 0.001) in high (130 and 150) keV images. High keV images reduced the number of false negative non-unions based on consolidation grade with 5% (p = 0.283). Agreement between observers regarding location of consolidation and non-union type did not improve in 130 and 150 keV images. Diagnostic confidence improved from 1.43 to 2.37 in high keV images compared to 70 keV images (p < 0.001). Overall diagnostic confidence was higher in intramedullary nails than plates (p < 0.05). CONCLUSIONS: Use of virtual monochromatic 130 and 150 keV dual-energy CT compared to 70 keV images improves the evaluation of suspected non-union of the appendicular skeleton treated with titanium or stainless steel intramedullary nails and plates.

Computer-assisted oblique single-cut rotation osteotomy to reduce a multidirectional tibia deformity: case report.

The correction of multiplanar deformity is challenging. We describe preoperative 3-D planning and treatment of a complex tibia malunion using an oblique single-cut rotation osteotomy to correct deformity parameters in the sagittal, coronal and transverse plane. At 5 years postoperatively, the patient ambulates without pain with a well-aligned leg.

Can experienced surgeons predict the additional value of a CT scan in patients with displaced intra-articular distal radius fractures?

There are no clear guidelines when an additional CT scan should be obtained for the treatment of displaced intra-articular distal radius fractures (DRF). This study aimed to investigate whether surgeons can predict the usefulness of CT scans to facilitate choice of treatment plan and/or pre-operative planning for DRF. Four surgeons evaluated 51 patients with displaced DRF. The choice of treatment (operative or nonoperative) was based on conventional radiographs. Subsequently, the surgeons were asked whether they would have requested an additional CT scan to determine this treatment choice, and also whether they required a CT scan for pre-operative planning. After 4 weeks, the additional CT scan was provided and the cases were assessed again. Based on these data, we calculated the number needed to scan (NNS) and number needed to harm (NNH) for two decision models. Model 1: Only provide a CT scan if the surgeon requested one based on their judgment of the X-rays. Model 2: CT scans for all displaced intra-articular DRF. For choice of treatment, the NNS was lower for model 1 than for model 2 (2.6 vs. 4.3) and the NNH is higher for model 1 (3.1 vs. 1.3). For pre-operative planning, the NNS (1.3 vs. 1.4) and NNH (3.7 vs. 3.4) were comparable for both models. Surgeons are able to predict the usefulness of an additional CT scan for intra-articular displaced DRF for OR indication. However, for pre-operative planning the usefulness of a CT scan is much harder to predict.

CRIPTO and its signaling partner GRP78 drive the metastatic phenotype in human osteotropic prostate cancer.

CRIPTO (CR-1, TDGF1) is a cell surface/secreted oncoprotein actively involved in development and cancer. Here, we report that high expression of CRIPTO correlates with poor survival in stratified risk groups of prostate cancer (PCa) patients. CRIPTO and its signaling partner glucose-regulated protein 78 (GRP78) are highly expressed in PCa metastases and display higher levels in the metastatic ALDHhigh sub-population of PC-3M-Pro4Luc2 PCa cells compared with non-metastatic ALDHlow. Coculture of the osteotropic PC-3M-Pro4Luc2 PCa cells with differentiated primary human osteoblasts induced CRIPTO and GRP78 expression in cancer cells and increases the size of the ALDHhigh sub-population. Additionally, CRIPTO or GRP78 knockdown decreases proliferation, migration, clonogenicity and the size of the metastasis-initiating ALDHhigh sub-population. CRIPTO knockdown reduces the invasion of PC-3M-Pro4Luc2 cells in zebrafish and inhibits bone metastasis in a preclinical mouse model. These results highlight a functional role for CRIPTO and GRP78 in PCa metastasis and suggest that targeting CRIPTO/GRP78 signaling may have significant therapeutic potential.

Connective Tissue Degeneration: Mechanisms of Palmar Fascia Degeneration (Dupuytren's Disease).

Dupuytren's disease is a connective tissue disorder of the hand causing excessive palmar fascial fibrosis with associated finger contracture and disability. The aetiology of the disease is heterogeneous, with both genetic and environmental components. The connective tissue is abnormally infiltrated by myofibroblasts that deposit collagen and other extracellular matrix proteins. We describe the clinical profile of Dupuytren's disease along with current therapeutic schemes. Recent findings on molecular and cellular parameters that are dysregulated in Dupuytren's disease, which may contribute to the onset of the disease, and the role of resident inflammation promoting fibrosis, are highlighted. We review recent literature focusing on non-myofibroblast cell types (stem cell-like cells), their pro-inflammatory and pro-fibrotic role that may account for abnormal wound healing response.

Computer-assisted 3D planned corrective osteotomies in eight malunited radius fractures.

In corrective osteotomy of the radius, detailed preoperative planning is essential to optimising functional outcome. However, complex malunions are not completely addressed with conventional preoperative planning. Computer-assisted preoperative planning may optimise the results of corrective osteotomy of the radius. We analysed the pre- and postoperative radiological result of computer-assisted 3D planned corrective osteotomy in a series of patients with a malunited radius and assessed postoperative function. We included eight patients aged 13-64 who underwent a computer-assisted 3D planned corrective osteotomy of the radius for the treatment of a symptomatic radius malunion. We evaluated pre- and postoperative residual malpositioning on 3D reconstructions as expressed in six positioning parameters (three displacements along and three rotations about the axes of a 3D anatomical coordinate system) and assessed postoperative wrist range of motion. In this small case series, dorsopalmar tilt was significantly improved (p = 0.05). Ulnoradial shift, however, increased by the correction osteotomy (6 of 8 cases, 75 %). Postoperative 3D evaluation revealed improved positioning parameters for patients in axial rotational alignment (62.5 %), radial inclination (75 %), proximodistal shift (83 %) and volodorsal shift (88 %), although the cohort was not large enough to confirm this by statistical significance. All but one patient experienced improved range of motion (88 %). Computer-assisted 3D planning ameliorates alignment of radial malunions and improves functional results in patients with a symptomatic malunion of the radius. Further development is required to improve transfer of the planned position to the intra-operative bone. Level of evidence IV.

Spectrum bias, a common unrecognised issue in orthopaedic agreement studies: do CT scans really influence the agreement on treatment plans in fractures of the distal radius?

OBJECTIVES: Current studies on the additional benefit of using computed tomography (CT) in order to evaluate the surgeons' agreement on treatment plans for fracture are inconsistent. This inconsistency can be explained by a methodological phenomenon called 'spectrum bias', defined as the bias inherent when investigators choose a population lacking therapeutic uncertainty for evaluation. The aim of the study is to determine the influence of spectrum bias on the intra-observer agreement of treatment plans for fractures of the distal radius. METHODS: Four surgeons evaluated 51 patients with displaced fractures of the distal radius at four time points: T1 and T2: conventional radiographs; T3 and T4: radiographs and additional CT scan (radiograph and CT). Choice of treatment plan (operative or non-operative) and therapeutic certainty (five-point scale: very uncertain to very certain) were rated. To determine the influence of spectrum bias, the intra-observer agreement was analysed, using Kappa statistics, for each degree of therapeutic certainty. RESULTS: In cases with high therapeutic certainty, intra-observer agreement based on radiograph was almost perfect (0.86 to 0.90), but decreased to moderate based on a radiograph and CT (0.47 to 0.60). In cases with high therapeutic uncertainty, intra-observer agreement was slight at best (-0.12 to 0.19), but increased to moderate based on the radiograph and CT (0.56 to 0.57). CONCLUSION: Spectrum bias influenced the outcome of this agreement study on treatment plans. An additional CT scan improves the intra-observer agreement on treatment plans for a fracture of the distal radius only when there is therapeutic uncertainty. Reporting and analysing intra-observer agreement based on the surgeon's level of certainty is an appropriate method to minimise spectrum bias. Cite this article: Bone Joint Res 2015;4:190-194.

BMP signaling components are expressed in human fracture callus.

Of the various growth factors involved in the healing response after a fracture, bone morphogenetic proteins (BMPs) are emerging as key modulators. BMPs exert their effects by binding to a complex of type I and type II receptors leading to the phosphorylation of specific downstream effector proteins called Smads. The current study examined the presence of BMP signaling components in human callus obtained from five nascent malunions undergoing fracture fixation. These callus samples represented various stages of bone healing and a mixture of endochondral and intramembraneous bone healing. We performed immunohistochemistry on the callus, using antibodies for BMP (BMP-2,-3,-4,-7), their receptors (BMPR-IA, -IB, -II), and phosphorylated BMP receptor-regulated Smads (pBMP-R-Smads). Active osteoblasts showed fairly consistent positive staining for all BMPs that were examined, with the immunoreactivity most intense for BMP-7 and BMP-3. Immunostaining for BMPs in osteoblasts appeared to colocalize with the expression of BMPR-IA, -IB, and -II. Positive immunostaining for pBMP-R-Smads suggests that the BMP receptors expressed in these cells are activated. Staining for BMPs in cartilage cells was variable. The immunostaining appeared stronger in more mature cells, whereas staining for BMP receptors in cartilage cells was less ubiquitous. However, the expression of pBMP-R-Smads in cartilage cells suggests active signal transduction. Fibroblast-like cells also had a variable staining pattern. Overall, our findings indicate the presence of BMPs, their various receptors, and activated forms of receptor-regulated Smads in human fracture callus. To the best of our knowledge, this is the first study that documents the expression of these proteins in human fracture tissue. Complete elucidation of the roles of BMP in bone formation will hopefully lead to improved fracture healing care.

Suramin inhibits growth and transforming growth factor-beta 1 (TGF-beta 1) binding in osteosarcoma cell lines.

Autocrine production of growth factors has been shown to be involved in the multistep process of tumorigenesis. The ability of suramin, a polyanionic anti-parasitic drug, to block growth factor-induced cell proliferation makes it a potential antineoplastic drug. We studied the effects of suramin on seven osteosarcoma cell lines. Using clinically achievable concentrations of suramin (50-400 micrograms/ml), we found a time- and dose-dependent inhibition of [3H]thymidine incorporation. We also showed that suramin is able, dose-dependently, to prevent binding of transforming growth factor (TGF)-beta 1 to its receptors. DNA synthesis inhibition by suramin was attenuated by TGF-beta 1 in some cell lines. Two cell lines that were inhibited by TGF-beta 1 were affected similarly by suramin as cell lines that were stimulated by TGF-beta 1. In conclusion, in five out of seven osteosarcoma cell lines, we showed a correlation between inhibition of growth factor-stimulated mitogenesis and binding of TGF-beta 1 to its receptor. Similar effects in TGF-beta 1-inhibited osteosarcoma cell lines suggest involvement of other mechanisms and/or growth factors. However, suramin proves to be a potent inhibitor of osteosarcoma cell proliferation in vitro.

Stress urinary incontinence: effect of pelvic muscle exercise.

Twenty women with stress urinary incontinence diagnosed by urodynamic testing participated in a 6-week pelvic muscle exercise program. The aim of the study was to evaluate the effectiveness of the exercise program, with or without an intravaginal balloon, on urinary leakage as determined by a 30-minute and a 24-hour pad test. Relative strength of the pelvic muscles was evaluated using an intravaginal device that measures the pressure generated during a muscle contraction. After completion of the exercise program, 18 of the 20 subjects had an increase in strength of the pelvic floor muscles, as demonstrated by increased intravaginal pressure or a decrease in urinary loss on the 24-hour pad test. The use of an intravaginal balloon did not improve performance of the pelvic muscles or decrease urinary loss as compared with the subjects who exercised without an intravaginal balloon. Twelve months after the completion of the exercise program, 19 of the participants responded to a questionnaire about their urinary loss and performance of pelvic muscle exercises. None of the subjects stated that her urinary loss was worse, three had undergone surgical intervention, and ten had not continued to exercise. Seven subjects still exercised, with subjective improvement of urinary loss. It appears that pelvic muscle exercises may be successful in improving the condition of stress urinary incontinence; however, half of the subjects did not continue to exercise independently.

Early lesions of the labrum and acetabular cartilage in osteonecrosis of the femoral head.

Osteonecrosis of the femoral head can be caused by a variety of disorders and affects the relatively young patient. Most studies have concentrated on the femoral changes; the sites of early lesions of the labrum and acetabular cartilage have not been recorded. We studied 17 hips with osteonecrosis and a wide congruent joint space on radiographs and by direct inspection of the femoral head, labrum and acetabular cartilage during surgery. All of the femoral heads had some anterosuperior flattening which reduced the head-neck ratio in this area. A consistent pattern of damage to the labrum and the acetabular cartilage was seen in all hips. Intraoperatively, impingement and the cam-effect with its spatial correlation with lesions of the labrum and acetabular cartilage were observed. These findings could be helpful when undertaking conservative surgery for osteonecrosis, since the recognition of early radiologically undetectable acetabular lesions may require modification of the surgical technique.