A lack of consensus in the assessment of fracture healing among orthopaedic surgeons

Definition of long-bone nonunion: A scoping review of prospective clinical trials to evaluate current practice

AIM

Although nonunions are among the most common complications after long-bone fracture fixation, the definition of fracture nonunion remains controversial and varies widely. The aim of this study was to identify the definitions and diagnostic criteria used in the scientific literature to describe nonunions after long-bone fractures.

METHODS

A comprehensive literature search was performed in PubMed, Cochrane Library, Web of Science, and Embase. Prospective clinical studies, in which adult long-bone fracture nonunions were investigated as main subject, were included in this analysis. Data on nonunion definitions described in each study were extracted and collected in a database.

RESULTS

Although 148 studies met the inclusion criteria, only 50% (74/148) provided a definition for their main study subject. Nonunion was defined in these studies based on time-related criteria in 85% (63/74), on radiographic criteria in 62% (46/74), and on clinical criteria in 45% (33/74). A combination of clinical, radiographic and time-related criteria for definition was found in 38% (28/74). The time interval between fracture and the time point when authors defined an unhealed fracture as a nonunion showed considerable heterogeneity, ranging from three to twelve months.

CONCLUSION

In the current orthopaedic literature, we found a lack of consensus with regard to the definition of long-bone nonunions. Without valid and reliable definition criteria for nonunion, standardization of diagnostic and treatment algorithms as well as the comparison of clinical studies remains problematic. The lack of a clear definition emphasizes the need for a consensus-based approach to the diagnosis of fracture nonunion centred on clinical, radiographical and time-related criteria.

Contrast-Enhanced Ultrasound: A Viable Diagnostic Tool in Predicting Treatment Failure after Non-union Revision Surgery for Upper- and Lower-Limb Non-unions

Non-unions remain a major complication in the treatment of long-bone fractures and affect quality of life considerably. Both early detection and treatment of non-unions are essential to secure subsequent fracture union. Sufficient vascularization plays a key role in the healing process. The aim of this prospective study was to quantify the microperfusion within non-unions by means of contrast-enhanced ultrasound (CEUS) as early as 12 wk after non-union surgery and to examine the prognostic capability of CEUS in predicting treatment failure. Among 112 patients who had undergone non-union surgery, consolidation within 36 mo was achieved in 89 patients ("responders"), whereas 23 patients showed persistent non-unions ("non-responders") and required further surgery. CEUS quantification parameters such as peak enhancement, wash-in area under the curve and wash-in perfusion index revealed significantly higher perfusion levels in "responders" compared with "non-responders" (p < 0.05). Receiver operator characteristic curve analysis revealed that persistent fracture non-unions could be predicted with a sensitivity/specificity of 88.7%/72.2% in lower-limb non-unions and a sensitivity/specificity of 66.7%/100.0% in upper-limb non-unions. CEUS is a suitable diagnostic tool in predicting treatment failure as early as 12 wk after non-union surgery and should be integrated into the clinical routine when deciding on revision surgery at an early stage.

Pilot study of micromotion nailing for mechanical stimulation of tibial fracture healing

Aims

The study objective was to prospectively assess clinical outcomes for a pilot cohort of tibial shaft fractures treated with a new tibial nailing system that produces controlled axial interfragmentary micromotion. The hypothesis was that axial micromotion enhances fracture healing compared to static interlocking.

Methods

Patients were treated in a single level I trauma centre over a 2.5-year period. Group allocation was not randomized; both the micromotion nail and standard-of-care static locking nails (control group) were commercially available and selected at the discretion of the treating surgeons. Injury risk levels were quantified using the Nonunion Risk Determination (NURD) score. Radiological healing was assessed until 24 weeks or clinical union. Low-dose CT scans were acquired at 12 weeks and virtual mechanical testing was performed to objectively assess structural bone healing.

Results

A total of 37 micromotion patients and 46 control patients were evaluated. There were no significant differences between groups in terms of age, sex, the proportion of open fractures, or NURD score. There were no nonunions (0%) in the micromotion group versus five (11%) in the control group. The proportion of fractures united was significantly higher in the micromotion group compared to control at 12 weeks (54% vs 30% united; p = 0.043), 18 weeks (81% vs 59%; p = 0.034), and 24 weeks (97% vs 74%; p = 0.005). Structural bone healing scores as assessed by CT scans tended to be higher with micromotion compared to control and this difference reached significance in patients who had biological comorbidities such as smoking.

Conclusion

In this pilot study, micromotion fixation was associated with improved healing compared to standard tibial nailing. Further prospective clinical studies will be needed to assess the strength and generalizability of any potential benefits of micromotion fixation.

Cite this article: Bone Jt Open 2021;2(10):825–833.

Effect of Bone Morphogenetic Protein-2 in the Treatment of Long Bone Non-Unions

Background: Delayed fracture healing continues to cause significant patient morbidity and an economic burden to society. Biological stimulation of non-unions includes application of recombinant bone morphogenetic protein-2 (rhBMP-2). However, rhBMP-2 use continues to be a matter of controversy as literature shows scarce evidence for treatment effectiveness. Questions: The objective of this study was to evaluate the effectiveness of rhBMP-2 treatment on long bone non-unions measuring union rate and time to union. Furthermore, we assess risk factors for treatment failure. Methods and patients: A total of 91 patients with non-unions of long bones were treated with rhBMP-2 (n = 72) or standard care without BMP (n = 19) at our institution. Patient characteristics, comorbidities, nicotine consumption, and complications were recorded. Bone healing was assessed by plane X-rays and clinical examination. Patients were followed up with for 24 months. Results: Overall, there was significantly faster bone healing after rhBMP-2 application compared to the no-BMP group (p < 0.001; HR = 2.78; 95% CI 1.4–5.6). Union rates differed significantly between rhBMP-2 compared to the no-BMP group (89% vs. 47%; p < 0.001). At the humerus, there was neither a significantly higher union rate in the rhBMP-2 (83%) compared to the no-BMP group (50%) (p = 0.26; n = 12) nor a faster bone healing with a median time of 9 months in both groups (HR = 2.01; 95% CI 0.49–8.61; p = 0.315). The 33 femora treated using rhBMP-2 healed significantly faster than 9 femora in the no-BMP group (HR = 2.93; 95% CI 1.00–8.4; p = 0.023) with significant differences in union rate with 85% and 44%, respectively (p = 0.022). Regarding tibia non-unions, 25 out of 27 (93%) healed with a median of 9 months after rhBMP-2 application with no significant difference in the no-BMP group (33%) in time to union (p = 0.097) but a significantly higher union rate (p = 0.039). There was no effect of comorbidities, age, sex, soft tissue damage, or nicotine use on time to union, union rate, or secondary interventions. Conclusion: Consistent with the literature, overall, significantly higher union rates with reduced time to union were achieved after rhBMP-2 application. Femoral and tibial non-unions in particular seem to profit from rhBMP-2 application.

Sensitivity and specificity of modified RUST score using clinical and radiographic findings as a gold standard

Aims

The modified Radiological Union Scale for Tibia (mRUST) fractures score was developed in order to assess progress to union and define a numerical assessment of fracture healing of metadiaphyseal fractures. This score has been shown to be valuable in predicting radiological union; however, there is no information on the sensitivity, specificity, and accuracy of this index for various cut-off scores. The aim of this study is to evaluate sensitivity, specificity, accuracy, and cut-off points of the mRUST score for the diagnosis of metadiaphyseal fractures healing.

Methods

A cohort of 146 distal femur fractures were retrospectively identified at our institution. After excluding AO/OTA type B fractures, nonunions, follow-up less than 12 weeks, and patients aged less than 16 years, 104 sets of radiographs were included for analysis. Anteroposterior and lateral femur radiographs at six weeks, 12 weeks, 24 weeks, and final follow-up were separately scored by three surgeons using the mRUST score. The sensitivity and specificity of mean mRUST score were calculated using clinical and further radiological findings as a gold standard for ultimate fracture healing. A receiver operating characteristic curve was also performed to determine the cut-off points at each time point.

Results

The mean mRUST score of ten at 24 weeks revealed a 91.9% sensitivity, 100% specificity, and 92.6% accuracy of predicting ultimate fracture healing. A cut-off point of 13 points revealed 41.9% sensitivity, 100% specificity, and 46.9% accuracy at the same time point.

Conclusion

The mRUST score of ten points at 24 weeks can be used as a viable screening method with the highest sensitivity, specificity, and accuracy for healing of metadiaphyseal femur fractures. However, the cut-off point of 13 increases the specificity to 100%, but decreases sensitivity. Furthermore, the mRUST score should not be used at six weeks, as results show an inability to accurately predict eventual fracture healing at this time point.

Cite this article: Bone Jt Open 2021;2(10):796–805.

Diagnostic prediction of ovine fracture healing outcomes via a novel multi-location direct electromagnetic coupling antenna

Background

Expedient prediction of adverse bone fracture healing (delayed- or non-union) is necessary to advise secondary treatments for improving healing outcome to minimize patient suffering. Radiographic imaging, the current standard diagnostic, remains largely ineffective at predicting nonunions during the early stages of fracture healing resulting in mean nonunion diagnosis times exceeding six months. Thus, there remains a clinical deficit necessitating improved diagnostic techniques. It was hypothesized that adverse fracture healing expresses impaired biological progression at the fracture site, thus resulting in reduced temporal progression of fracture site stiffness which may be quantified prior to the appearance of radiographic indicators of fracture healing (i.e., calcified tissue).

Methods

A novel multi-location direct electromagnetic coupling antenna was developed to diagnose relative changes in the stiffness of fractures treated by metallic orthopaedic hardware. The efficacy of this diagnostic was evaluated during fracture healing simulated by progressive destabilization of cadaveric ovine metatarsals treated by locking plate fixation (n=8). An ovine in vivo comparative fracture study (n=8) was then utilized to better characterize the performance of the developed diagnostic in a clinically translatable setting. In vivo measurements using the developed diagnostic were compared to weekly radiographic images and postmortem biomechanical, histological, and micro computed tomography analyses.

Results

For all cadaveric samples, the novel direct electromagnetic coupling antenna displayed significant differences at the fracture site (P<0.05) when measuring a fully fractured sample versus partially intact and fully intact fracture states. In subsequent in vivo fracture models, this technology detected significant differences (P<0.001) in fractures trending towards delayed healing during the first 30 days post-fracture.

Conclusions

This technology, relative to traditional X-ray imaging, exhibits potential to greatly expedite clinical diagnosis of fracture nonunion, thus warranting additional technological development.

Non-union bone fractures

The human skeleton has remarkable regenerative properties, being one of the few structures in the body that can heal by recreating its normal cellular composition, orientation and mechanical strength. When the healing process of a fractured bone fails owing to inadequate immobilization, failed surgical intervention, insufficient biological response or infection, the outcome after a prolonged period of no healing is defined as non-union. Non-union represents a chronic medical condition not only affecting function but also potentially impacting the individual's psychosocial and economic well-being. This Primer provides the reader with an in-depth understanding of our contemporary knowledge regarding the important features to be considered when faced with non-union. The normal mechanisms involved in bone healing and the factors that disrupt the normal signalling mechanisms are addressed. Epidemiological considerations and advances in the diagnosis and surgical therapy of non-union are highlighted and the need for greater efforts in basic, translational and clinical research are identified.

Determining the development stage of the ossification centers around the elbow may aid in deciding whether to use ESIN or not in adolescents' forearm shaft fractures

Background and purpose - Elastic stable intramedullary nailing (ESIN) is the preferred method of operative stabilization of unstable pediatric forearm shaft fractures. However, the decision whether to use ESIN or open reduction and internal fixation (ORIF) in older children or teenagers is not always straightforward. We hypothesized that the development stage of the elbow would aid in evaluating the eligibility of the patient for ESIN.Patients and methods - All eligible children, aged <16 years who were treated with ESIN in Oulu University Hospital, during 2010-2019 were included (N = 70). The development stages of 4 ossification centers were assessed according to the Sauvegrain and Diméglio scoring. The proportion of impaired union vs. union was analyzed according to bone maturity, by using the optimal cutoff-points determined with receiver operating characteristics (ROC).Results - Development stage ≥ 6 in the olecranon was associated with impaired union in 20% of patients, compared with none in stages 1-5 (95% CI of difference 8% to 24%). Trochlear ossification center ≥ 4 was associated with impaired union in 17% of patients (CI of difference 7% to 36%) and lateral condyle ≥ 6 in 13% of patients (CI of difference 3.4% to 30%). Proximal radial head ≥ 5.5 was associated with impaired union in 18% of patients (CI of difference 7% to 39%).Interpretation - Recognizing the rectangular or fused olecranon ossification center, referring to stage ≥ 6, was in particular associated with impaired fracture healing. This finding may aid clinicians to consider between ESIN and plating, when treating forearm shaft fracture of an older child or teenager.

The orthopaedic surgeon's clinical and experimental experience affect methods used for the fracture healing assessment (FHA) - An International Survey

Detection of fracture healing (FH), which depends on assessment methods, is a crucial factor affecting treatment. The study aimed to examine orthopedic surgeons in terms of practical methods of fracture healing (FHA) assessment (physical, imaging, measurement, and laboratory) and to check whether surgeons participating in clinical and laboratory experiments or only clinical practitioners prefer different FHA methods. An International Survey on Fracture Healing Assessment Methods was developed and distributed through the Web-based survey portal. Ninety-three orthopedic surgeons, on average age 41.46 years, from 24 countries participated in the study. Thirty-one respondents (33.3%) reported dealing with fractures both in the clinic and in experimental studies, six (6.5%) reported dealing with fractures only in laboratory research work, and fifty-six (60.2%) indicated that they dealt with fractures only clinically. The survey's internal consistency was significantly high (Cronbach's alpha coefficients ranged from 0.84 to 0.96). The majority of respondents (80.83%) use specific clinical criteria to define a fracture union. The FHA was mainly based on the physical examination and plain radiograms. Laboratory findings, patient-oriented outcomes scores, and quantitative methods are rarely used. Orthopaedic surgeons dealing with fractures both in the clinic and in laboratory fracture research studies are more likely to use more quantitative FHA methods. Future research is needed to improve the international standard of the FHA methods for use in research, clinical trials, and clinical practice. Using a quantitative, reliable, and standardized approach, including online support, can be valuable for increasing compliance in the orthopedic surgeon population, effectively improving the adherence of fracture healing assessment in clinical conditions, and improving early detection of fracture healing disorders, improving fracture efficiency treatment.

Development of a novel atrophic non-union model in rabbits: A preliminary study

Background and aim

The currently available atrophic non-union models rely on wide segmental excision of bone diaphysis to impede the process of healing but lack resemblance to the clinical scenario. The present study focused on developing an in vivo model of atrophic non-union fracture in rabbit radius that can replicate the clinical scenario.

Materials and methods

The atrophic non-union fracture model was developed by creating a 10 mm segmental bone defect in the radial diaphysis of five adult New Zealand White rabbits. The periosteum (2 mm) of the cut bone ends was cauterized using electrocautery to induce atrophy. Atrophic non-union was confirmed using radiographic and histologic evaluations on 30th postoperative day.

Results

The radiographic signs of healing were completely absent in all the rabbits on 30th postoperative day, indicating inert bone ends. Histological findings further confirmed the presence of inert bone ends, indicating the development of atrophic non-union.

Conclusion

The combination of the segmental bone defect, electrocautery induced thermal damage of bone end periosteum, and delayed treatment can induce the development of atrophic non-union fracture model in rabbits that can replicate the clinical scenario.

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In vivo model of atrophic non-union fracture in rabbit radius was developed that can replicate the clinical scenario.

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Radiographic and histological findings confirmed the presence of inert bone ends.

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Combination of segmental bone defect, electrocautery induced thermal damage, and delayed treatment can induce atrophic non-union fracture.

Restoration of Stiffness During Fracture Healing at the Distal Radius, Using HR-pQCT and Finite Element Methods

Finite element analysis (FE) coupled with high-resolution peripheral quantitative computed tomography (HR-pQCT) allows for noninvasive in vivo assessment of fracture stiffness at peripheral locations including the distal radius. Previous studies have reported the ability of FE analysis to capture significant longitudinal changes in fracture stiffness. We hypothesized that continuum-based FE methods are necessary to capture significant changes in FE-estimated stiffness in men and women, with closed reductions and casting, over the course of their fracture healing process. The primary aim of the study was to evaluate the performance of 3 micro-FE (μFE) methods, 2 density-based (continuum) methods, and a homogeneous method. A total of 30 participants with stable distal radius fractures completed follow-ups at 2, 4, 6, 8, 12, and 26 weeks postfracture. Participants had their fractured wrist scanned using HR-pQCT at each follow-up; the contralateral wrist was also scanned at the initial assessment to represent baseline conditions. Images were used to generate continuum and homogeneous µFE models. Uniaxial compression and torsional tests were completed, with apparent stiffness determined as the primary outcome measure. Stiffness of the fractured wrist was compared to stiffness of the uninjured contralateral wrist to quantify the change in stiffness. Days since fracture significantly predicted change in stiffness for continuum and homogeneous µFE methods (p < 0.05). Continuum µFE methods appeared to account for partially mineralized tissues, resulting in a graduated recovery of stiffness (1% per week). Homogeneous µFE methods were more sensitive to stages of healing progression, resulting in a faster recovery of stiffness (3% per week). Our findings demonstrate the capability of µFE to capture the restoration of stiffness at the fractured side to prefracture stiffness in men and women, up to 6 months postfracture.

Percutaneous Reduction and 2.7-mm Cortical Screw Fixation for Low-Energy Lisfranc Injuries

To use the advantages of transarticular screw fixation while minimizing iatrogenic involved joint damage and screw irritation, it is important to determine the screw size. The aim of this study was to analyze the outcomes of percutaneous reduction and 2.7-mm cortical screw fixation for low-energy Lisfranc injuries and determine whether the procedure is a safe alternative to traditional screw fixation using a larger screw size. A review was performed for all patients who underwent percutaneous reduction and 2.7-mm cortical screw fixation for low-energy Lisfranc injuries at a single institution over a 6-year period. Thirty-one patients were enrolled in this study. Patients were assessed clinically and radiographically for demographics, foot function index (FFI), numerical rating scale (NRS) for pain, patient satisfaction, and complication rates. Factors affecting screw breakage and its clinical relevance were also analyzed. The FFI and NRS for pain were 17.2 ± 14.7 (range 0.8 to 57.8) and 3.1 ± 2.3 (range 0 to 8) points, respectively, at the 12-month follow-up visit. One patient (3.2%) underwent arthrodesis for the development of posttraumatic arthritis; all other patients recovered without sequelae. Screw breakage was identified in 7 patients (22.6%). There was no significant difference between patients with and without screw breakage in terms of FFI, NRS for pain, patient satisfaction, or complication rate. Body mass index (BMI) was significantly higher in patients with screw breakage than in those without screw breakage. Receiver operator characteristics curve analysis demonstrated a strong relationship between BMI and screw breakage (area under the curve = 90%, p < .001), and the potential BMI cutoff value was 27.8 kg/m². After considering the incidence of screw breakage, percutaneous reduction and 2.7-mm cortical screw fixation can be a viable option for treating low-energy Lisfranc injuries in nonobese patients, especially those with BMI <27.8 kg/m².

Combining a Vascular Bundle and 3D Printed Scaffold with BMP-2 Improves Bone Repair and Angiogenesis

Vascularization is currently considered the biggest challenge in bone tissue engineering due to necrosis in the center of large scaffolds. We established a new expendable vascular bundle model to vascularize a three-dimensional printed channeled scaffold with and without bone morphogenetic protein-2 (BMP-2) for improved healing of large segmental bone defects. Bone formation and angiogenesis in an 8 mm critical-sized bone defect in the rat femur were significantly promoted by inserting a bundle consisting of the superficial epigastric artery and vein into the central channel of a large porous polycaprolactone scaffold. Vessels were observed sprouting from the vascular bundle inserted in the central tunnel. Although the regenerated bone volume in the group receiving the scaffold and vascular bundle was similar to that of the healthy femur, the rate of union of the group was not satisfactory (25% at 8 weeks). BMP-2 delivery was found to promote not only bone formation but also angiogenesis in the critical-sized bone defects. Both insertion of the vascular bundle alone and BMP-2 loading alone induced comparable levels of angiogenesis and when used in combination, significantly greater vascular volume was observed. These findings suggest a promising new modality of treatment in large bone defects. Level of Evidence: Therapeutic level I.

Smart implants in fracture care - only buzzword or real opportunity?

The assessment of fracture healing is still marked by a subjective and diffuse outcome due to the lack of clinically available quantitative measures. Without reliable information on the progression of healing and uniform criteria for union and non-union, therapeutic decision making, e.g. regarding the allowed weight bearing, hinges on the experience and the subjective evaluation of physicians. Already decades ago, fracture stiffness has been identified as a valid outcome measure for the maturity of the repair tissue. Despite early promising results, so far no method has made its way into practice beyond clinical studies. However, with current technological advancements and a general trend towards digital health care, measuring fracture healing seems to regain momentum. New generations of instrumented implants with sensoring capabilities, often termed as "smart implants", are under development. They target X-ray free and timely provision of reliable feedback upon the mechanical competence of the repair tissue and the healing environment to support therapeutic decision making and individualized after-care. With the gained experience from these devices, the next generations of smart implants may become increasingly sophisticated by internally analyzing the measured data and suggesting adequate therapeutic actions on their own.

Squat and smile assessment in predicting healing of lower limb fractures fixed with a SIGN nail

BACKGROUND

Irrespective of the treatment method, union is the ultimate goal of any fracture treatment. However, nowadays, rather than the physician-based clinico-radiological methods, the patient-reported outcome measurements assessing their quality of life and function are gaining much popularity. This is specifically true in the part of the world where the patient needs almost complete degree of hip/knee flexion - for social, cultural, religious or occupational reason(s). The ability to squat can assess the mobility and stability of joints and thus the quality of squatting is a proxy reflection of the functional outcome after fixation of lower limb fracture. Thus, we studied to determine the inter-observer and intra-observer reliability of Radiographic Union Score for Tibia (RUST) and Squat and Smile (S & S) test in clinical photograph. We further calculated the sensitivity and specificity of S & S test in predicting healing of lower limb fracture fixed by intramedullary interlocking nail considering RUST as the gold standard.

METHODS

This was a retrospective study of prospectively collected data of solid Surgical Implant Generation Network (SIGN) intramedullary interlocking nailing from a single, university-based, high volume tertiary center where 56 consecutive adults with either tibial or femoral shaft fractures fixed with a SIGN nail within one year and not requiring any surgery till minimum of eighteen-month follow-up were included. Cases without either Anterior-Posterior (AP) view and/or Lateral (Lat.) view follow-up x-ray(s) or proper S & S clinical photograph (at least 1.5-year post fixation) were excluded. The x-rays (RUST criteria) and clinical photograph (S & S grading) were scored by two independent and blinded observers each and repeated after 1 month.

RESULTS

The overall intra-observer reliability was from 0.773 to 0.825 and inter-observer reliability from 0.635 to 0.757 for RUST scoring which was from 0.687 to 0.785 and from 0.301 to 0.650 respectively for S & S scoring. The sensitivity and specificity of S & S in predicting fracture healing were up to 82.22% and 63.64% respectively.

CONCLUSION

The S & S test is reliable to predict the healing of lower limb fracture fixed with an intramedullary nail. The test is more useful to determine healed fractures than to determine non-healed ones. (sensitivity being higher than specificity).

Evaluating reliability and validity of the modified radiographic union scale for tibia (mRUST) among North American and Tanzanian surgeons

Objectives

To determine the international reliability and validity of the modified Radiographic Union Scale for Tibial fracture (mRUST) scoring method for open tibial shaft fractures based on ratings of radiographs by separate groups of North American and Tanzanian surgeons.

Methods

Seven North American and 9 Tanzanian surgeons viewed 100 pairs of AP and lateral radiographs of open tibial shaft fractures obtained in Dar Es Salaam, Tanzania. The radiographs showed 25 patients' fractures at 4 time points postfracture after treatment with either external fixation or intramedullary nailing. Surgeons evaluated each fracture using the mRUST scoring method and indicated their confidence that the fracture was healed on a scale from 1 to 10. Reliability of mRUST was determined using inter-rater agreement among North American and Tanzanian surgeons. Validity was determined via analysis of correlation between mRUST scores and EQ-5D-3L index scores at each time point postfracture.

Results

mRUST scores demonstrated strong reliability overall (ICC = 0.64) as well as within each group of North American (ICC = 0.72) and Tanzanian (ICC = 0.69) surgeons. Reliability was stronger for external fixation than for intramedullary nailing cases. mRUST scores were significantly correlated with overall healing confidence at all time points and with quality of life at 6 months and 1 year postfracture. mRUST scores also correlated significantly with patients' quality of life scores (EQ-5D index) at 6 months and 1 year postfracture.

Conclusion

North American and Tanzanian surgeons exhibited strong agreement in rating open tibial shaft fractures. Using mRUST scores is a valid means of assessing radiographic healing of tibial fractures in austere environments like Tanzania.

Effect of compression fracture on trabecular bone score at lumbar spine

Bone mineral density (BMD) may be increased due to vertebral compression fractures (VCF). Our study showed trabecular bone scores (TBS) was less affected than BMD by fractured vertebrae. The TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk.

INTRODUCTION

Trabecular bone score (TBS), a noninvasive tool estimating bone microarchitecture, provides complementary information to lumbar spine bone mineral density (BMD). Lumbar spine BMD might be increased due to both degenerative disease and vertebral compression fractures (VCF). Lumbar spine TBS has been confirmed not influenced by osteoarthrosis, but the effects of VCF are still not been well evaluated. This study aimed to investigate whether lumbar spine TBS was affected by fractured vertebrae.

METHODS

We studied postmenopausal women and men above 50 years old who underwent DXA between January 1, 2017, and May 31, 2019. By calculating the difference of BMD and TBS between L1 and the mean of L2-3, the study compared the difference of values between the control group and fracture group to determine the effects of fractured vertebrae on BMD and TBS.

RESULTS

A total of 377 participants were enrolled with 202 in the control group (157 females; age: 68.06 ± 6.47 years) and 175 in the fracture group (147 females; age: 71.71 ± 9.44 years). The mean BMD of the L1 vertebrae in the fracture group was significantly higher than that in the control group (p < 0.0001). There was no significant difference between the mean differences of TBS between L1 and the means of L2-3 vertebrae in the control group and the most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity.

CONCLUSION

Lumbar spine TBS, unlike BMD, is less affected by fractured vertebrae. The TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk.

Semi-quantitative CT scoring of nailed shaft fractures during normal healing and in non-unions: comparison with radiographic scoring

PURPOSE

To compare tomographic (TUS) with radiographic (RUS) union scores in nailed shaft fractures during normal healing and in non-unions.

METHODS

Two radiologists blinded to fracture age separately determined RUS and TUS in nailed femoral or tibial shaft fractures by analyzing the radiographic and CT examinations obtained in 47 patients during normal healing (early fracture group; 24 study participants, 17 men,19 tibias, mean fracture-CT delay 109 ± 57 days [42-204 days]) and in surgically proven non-united fractures (late fracture group, 23 patients, 14 men, 12 tibias, mean fracture-CT delay 565 ± 519 days[180-1983 days]). In both study groups, we determined the inter- and intra-observer agreement of RUS and TUS and compared TUS with RUS.

RESULTS

Intra- and inter-observer agreement of RUS and TUS was very good in the early fracture group and good in the late fracture group for both readers. TUS correlated with RUS substantially in the early fracture group and only weakly in the late fracture group. TUS was statistically significantly lower than RUS in study participants with RUS ≥ 8 or 9 for R2 only and ≥ 10 for both readers in the early fracture group and in patients with RUS ≥ 8, 9 or 10 in the late fracture group for both readers.

CONCLUSION

RUS and TUS of nailed shaft fractures during normal healing or in non-unions are both feasible and reproducible. They yield similar values in fractures with no or limited callus. TUS yields lower values than RUS in fractures with callus.

Expression of VEGF in Peripheral Serum Is a Possible Prognostic Factor in Bone-Regeneration via Masquelet-Technique-A Pilot Study

Two-step Masquelet-technique established a new procedure in the treatment of osseous defects, addressing prerequisites postulated by the “diamond concept”. Increase in blood perfusion and growth factors are enhanced by the “Masquelet-membrane”. To describe this, we measured serum levels of Vascular Endothelial Growth Factor (VEGF) of patients with atrophic non-unions of long bones undergoing Masquelet-technique. From over 500 non-union patients undergoing Masquelet-technique with prospective follow-up we randomly selected 30 patients. 23 were included, 7 lost to follow-up or excluded because of incomplete data. Serum was drawn at specified intervals before and after surgery. Patients were followed for at least 6 months after step 2. Classification into both groups was performed according to radiological results and clinical outcome 6 months after step 2. Concentration of VEGF in patients’ serum was performed via ELISA. 14 achieved osseous consolidation (responder group), 9 cases did not (non-responder). Responders showed a significant increase of serum-VEGF in the first and second week when compared to the preoperative values of step 1. Non-responders showed a significant increase of VEGF in the second week after Steps 1 and 2. Comparison of groups showed significantly higher increase of serum-VEGF week2 after step 1 and preoperative to step 2 for responders. Results show one possibility of illustrating therapeutic progress by monitoring growth factors and possibly allowing prognostic conclusions thereof. This might lead to a more targeted treatment protocol.

Improvements in radiographic and clinical assessment of distal radius fracture healing by FE-estimated bone stiffness

Bone strength determined from finite element (FE) modelling provides an estimate of fracture healing progression following a distal radius fracture (DRF), but how these measures relate to patient-reported outcomes and functional outcomes remains unknown. We hypothesized that changes in bone stiffness and bone mineral density measured using high-resolution peripheral quantitative computed tomography (HR-pQCT) are associated with clinically available measures of functional and patient-reported outcomes. We also aimed to identify which clinical outcome measures best predict fracture stiffness and could therefore be used to inform cast removal.

Participants (n = 30) with stable distal radius fractures were followed for two week intervals from the time of fracture until two months post-fracture, then at three months and six months post-fracture. At each follow-up, participants underwent clinical, radiographic, and functional assessments, as well as had their fractured wrist scanned using HR-pQCT. Recovery of bone stiffness during fracture healing was determined from micro-FE (μFE) models generated from HR-pQCT image data.

During the DRF healing process, significant longitudinal changes were found in μFE-estimated stiffness, patient-reported outcomes, grip strength, range of motion (ROM), tenderness, number of cortices healed based on radiographs, and fracture line visibility (p < 0.05); however, no significant change was detected in HR-pQCT based total bone mineral density. Patient-reported outcomes, such as the Patient-Rated Wrist Evaluation (PRWE) and the Quick Disability of the Arm, Shoulder and Hand (QuickDASH) questionnaire, correlated strongly with μFE-estimated stiffness (0.61 ≥ r_m ≥ 0.66). Based on μFE-estimated stiffness, PRWE and QuickDASH are the best predictors of stiffness recovery (p < 0.05) and may be used to guide duration of cast immobilization in the clinical setting.

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Recovery of fracture stiffness may inform time required for cast immobilization.

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Patient reported outcomes predict rate of fracture stiffness recovery.

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Radiographic outcomes correlate weakly with fracture stiffness.

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Patient reported outcomes may inform duration of cast immobilization.

Reliability of radiographic union scale in tibial fractures and modified radiographic union scale in tibial fractures scores in the evaluation of pediatric forearm fracture union

Objectives

This study aims to evaluate the reliability of the radiographic union scale in tibial (RUST) fractures and modified RUST (mRUST) fractures in pediatric forearm fractures treated with elastic stable intramedullary nail (ESIN) and to investigate the effect of the experience of surgeon, thresholds for union, and delayed union decisions.

Patients and methods

In this retrospective study, radiographic images of 20 patients (10 males, 10 females; mean age 8.6±4.3; range, 4 to 11 years) with forearm fractures treated using ESIN between January 2013 and December 2018 were scored by 20 observers based on the RUST and mRUST scores. The observers scored the radiographs at immediate postoperative period, and at 4-, 8-, and 12-week follow-up. Intra- and interobserver agreement for each cortex, RUST, and mRUST were evaluated using intraclass correlation coefficient (ICC). The Fleiss’ kappa (k) coefficient was used in the agreement between evaluators regarding union decision. Receiver operating curves were created to determine the thresholds for radiographic union and delayed union.

Results

Intra- and interobserver reliability of the mRUST score (ICC: 0.84 and 0.79) were slightly higher than that of the RUST score (ICC: 0.80 and 0.72). Pediatric orthopedic and trauma surgeons had slightly higher agreement than the residents and general orthopedists for the total mRUST and RUST scores of the eight-week radiographs. Mean RUST and mRUST scores at the union for all fractures were 10.2±3.4 and 13.0±2.1, respectively. Kappa value for union was moderate (0.74). The total mRUST score had a higher predictive value for union than the total RUST score (area under the curve: 0.986 vs. 0.889). A mRUST score of ≥12 and RUST score of ≥9 were considered as the predictors of union. In addition, a mRUST score of ≤7 and RUST score of <9 were considered as the predictors of delayed union.

Conclusion

A moderate agreement for both RUST and mRUST scores was found. However, the agreement for mRUST was found to be slightly higher. Healing and union of forearm fractures treated with ESIN can be reliably assessed using RUST and mRUST.

Overview of Skeletal Repair (Fracture Healing and Its Assessment)

The study of postnatal skeletal repair is of immense clinical interest. Optimal repair of skeletal tissue is necessary in all varieties of elective and reparative orthopedic surgical treatments. However, the repair of fractures is unique in this context in that fractures are one of the most common traumas that humans experience and are the end-point manifestation of osteoporosis, the most common chronic disease of aging. In the first part of this introduction the basic biology of fracture healing is presented. The second part discusses the primary methodological approaches that are used to examine repair of skeletal hard tissue and specific considerations for choosing among and implementing these approaches.

Radiographic Humerus Union Measurement (RHUM) Demonstrates High Inter- and Intraobserver Reliability in Assessing Humeral Shaft Fracture Healing

BACKGROUND

Orthopedic surgeons use radiographs to determine degrees of fracture healing, guide progression of clinical care, and assist in determining weight bearing and removal of immobilization. However, no gold standard exists to determine the progression of healing of humeral shaft fractures treated non-operatively.

PURPOSE

The purpose of this study was to determine whether a scale comparable to the modified Radiographic Union Score for Tibial (RUST) fractures applied to non-operatively treated humeral shaft fractures can increase interobserver reliability in determining fracture healing.

METHODS

A retrospective review was undertaken by three orthopedic traumatologists and one musculoskeletal radiologist, who evaluated 50 sets of anteroposterior and lateral radiographs, presented at random, of non-operatively treated humeral shaft fractures at various stages of healing from 17 patients. The radiographs were scored using a modified RUST scale called the Radiographic Humerus Union Measurement (RHUM). Observers were blinded to the time from injury. After a 4-week washout period, observers again scored the same radiographs. Observers classified each fracture as either healed or not healed based on the combination of radiographs. Inter- and intraobserver reliability of the RHUM were determined using an intraclass correlation coefficient (ICC). Interobserver reliability of determining a healed fracture was calculated using Cohen's kappa (κ) statistics. A receiver operator characteristic curve was conducted to determine the RHUM score predictive of a fracture being considered healed.

RESULTS

ICC demonstrated almost perfect interobserver reliability (ICC, 0.838; ICC 95% CI, 0.765 to 0.896) and intraobserver reliability (ICC range, 0.822 to 0.948) of the RHUM. κ demonstrated substantial agreement between observers in considering a fracture healed (κ = 0.647). Receiver operating characteristic (ROC) curve demonstrated that a RHUM of 10 or higher is an excellent predictor of the observer considering the fracture healed (area under the ROC curve = 0.946, specificity = 0.957, 95% CI specificity, 0.916 to 0.979).

CONCLUSIONS

This cortical scoring system has excellent interobserver reliability in humeral shaft fractures treated non-operatively. Consistent with previous cortical scoring systems, a RHUM score of 10 or above can be considered radiographically healed.

Frontiers in non-union research

Multifactorial aetiology defines non-unions, with a biological and a mechanical distortion of the timeline of bone healing.

Research on new advances to increase osteogenesis and promote non-union healing is strongly directed towards new forms of cell products.

Basic science and research on non-union treatments is needed to compile preclinical data on new treatments.

Bone marrow concentration and expanded mesenchymal stromal cells still require extensive clinical research to confirm efficacy in non-union treatment.

Solid preclinical studies, precise cell product definition and preparation, and appropriate ethical and regulatory approvals are needed to assess new advanced therapy medicinal products.

Cite this article: EFORT Open Rev 2020;5:574-583. DOI: 10.1302/2058-5241.5.190062

Nonunion and Reoperation After Ulna Shortening Osteotomy

Background: The primary purpose of our study was to identify factors associated with reoperation after ulna shortening osteotomy. Our secondary aims were to determine the rate and type of reoperation procedures. Methods: In this retrospective study, we included patients older than 18 years of age who underwent an ulna shortening osteotomy between January 2003 and December 2015. Medical records of patients were assessed for our explanatory variables, reoperations, and reporting of symptoms. We used bivariate and multivariable analyses to identify factors associated with reoperation after ulna shortening osteotomy. Results: Among 94 patients who underwent 98 ulna shortening osteotomies, there were 34 reoperations (35%). Nineteen patients (19%) underwent removal of hardware, 6 (6.1%) had a nonunion, and 9 (9.2%) underwent additional surgeries. Surgery on their dominant limb, trauma, and prior surgery to the ipsilateral wrist were associated with reoperation. In multivariable analysis, factors independently associated with reoperation were the dominant side being affected (odds ratio = 3.9; 95% confidence interval [CI] = 1.36-11) and traumatic origin (odds ratio = 3.4; 95% CI = 1.1-11). Bivariate analysis identified younger age and prior surgery of the affected wrist as factors associated with hardware removal. More operations for refixation due to nonunion of osteotomy were performed in patients with a transverse osteotomy compared with patients with an oblique osteotomy. Conclusions: One in 3 patients will undergo a reoperation after ulna shortening osteotomy, most often due to hardware irritation or nonunion of osteotomy. Awareness of these rates and predictive factors may be helpful for preoperative discussions and surgical decision making.

Analysis of fracture healing process by HR-pQCT in patients with distal radius fracture

INTRODUCTION

High-resolution peripheral quantitative computed tomography (HR-pQCT) has enabled us to observe the changes in bone microarchitecture over time in vivo. In this study, the process of fracture healing was analyzed using HR-pQCT in patients with distal radius fracture who underwent osteosynthesis.

MATERIALS AND METHODS

A total of 10 fracture sites identified from four patients with a distal radius fracture who underwent internal fixation with a volar locking plate (mean age 68.8 years, all women) were investigated. HR-pQCT was performed within a week (baseline) 4, 12, and 24 weeks after fracture. Rectangular region of interest (ROI) was established in the fracture site, inner callus, and external callus area, and the changes in bone mineral density (BMD) in each region were analyzed.

RESULTS

From baseline to 24 weeks post-fracture, the BMD changed from 105.5 (95% CI 98.6-113) to 428.0 (331-554) mgHA/ccm at the fracture site, from 111.0 (104-119) to 375.3 (290-486) mgHA/ccm at the inner callus area, and from 98.5 (91.6-106) to 171.6 (132-222) mgHA/ccm at the external callus area. The BMD increased at the fracture site and inner callus area, but increased only slightly at the external callus area. At 24 weeks post-fracture, the BMD at the fracture site and inner callus area was significantly higher than the external callus area.

CONCLUSION

In the healing process of postoperative distal radius fractures, increased BMD at the inner surface of the fracture site was confirmed in all fractures. Bone formation on the endosteal side may be a necessary condition for bone union of distal radius fractures.

Reliability of RUST and Modified RUST Scores for the Evaluation of Union in Humeral Shaft Fractures Treated with Different Techniques

BACKGROUND

The study aimed to evaluate the agreement between the radiographic union scale (RUST) and modified RUST (mRUST) in humeral shaft fractures treated with different techniques, and the effect of surgeons' experience and thresholds for determining bone union.

MATERIALS AND METHODS

A total of 20 orthopedic surgeons reviewed and scored radiographs of 30 patients with humeral shaft fractures treated by external fixation, intramedullary nailing, and plating using the RUST and mRUST on the 0 day, 6 weeks, 12 weeks and 24 weeks follow-up radiographs. Bone healing, interrater agreement between RUST and mRUST scores, and the threshold for radiographic union were evaluated.

RESULTS

The intraclass correlation coefficient (ICC) was slightly higher for the mRUST score than the RUST score (0.71 versus [vs.] 0.67). There was substantial agreement between the mRUST and RUST scores for external fixation (0.75 and 0.69, respectively) and intramedullary nailing (0.79 and 0.71); there was moderate agreement between them for plating (0.59 and 0.55). Surgeons with varying experience had a similar agreement for both scores and scores for each humeral cortex. The external fixation and intramedullary nailing group had higher RUST and mRUST scores than the plating group. The ICC for union was substantial (0.64; external fixation: 0.68, intramedullary nailing: 0.64, and plating: 0.61). More than 90% of the reviewers recorded scores of 10/12 for RUST and 13/16 for mRUST at the time of union.

CONCLUSIONS

RUST and mRUST scores can be used reliably for the evaluation of bony union in humeral fractures treated with an external fixator and intramedullary nailing. In cases of humeral plating, a more sensitive tool for evaluation of fracture union is needed.

Assessment of union in fractures: Role of Serum Alkaline Phosphatase and Ultrasonography

INTRODUCTION

Fracture union is a fundamental goal in orthopaedics. There is variability in assessment and lack of consensus on reliability of various methods to evaluate progress of union. The purpose of this study was to study the temporal association of non-conventional methods i.e. Serum Alkaline Phosphatase (ALP) and Ultrasound (USG) in assessment of fracture healing with reference to plain radiographs (X-ray).

METHODOLOGY

This was a prospective observational cohort study of 161 adult patients with surgically treated long bone diaphyseal fractures. Plain radiographs, ALP and USG evaluation was done every 6 weekly for 6 months. USG evaluation included assessment of echogenicity and Doppler measurement of Vascular Resistance Index (RI) of callus. Fractures were considered united when X-ray showed bridging callus. ALP and USG changes over the follow-up period were analysed based on the final outcome of fractures.

RESULTS AND CONCLUSION

151 patients showed signs of fracture union at final follow-up. ALP which peaked at 6 weeks in all cases always remained within the laboratory reference range in cases progressing to union; whereas in cases of non-union the levels recorded higher. ALP value was the earliest positive predictor showing progress towards union. Beyond 12 weeks, Hyperechogenicity on Gray scale USG and serial measurement of RI on Doppler USG were found to better confirm progress in fracture union than X-rays. Combined evaluations of ALP and USG appear as promising investigations in assessment of the progress in fracture union.

The Life of a Fracture: Biologic Progression, Healing Gone Awry, and Evaluation of Union

New knowledge about the molecular biology of fracture-healing provides opportunities for intervention and reduction of risk for specific phases that are affected by disease and medications. Modifiable and nonmodifiable risk factors can prolong healing, and the informed clinician should optimize each patient to provide the best chance for union. Techniques to monitor progression of fracture-healing have not changed substantially over time; new objective modalities are needed.

The Association Between Traumatic Brain Injury and Accelerated Fracture Healing: A Study on the Effects of Growth Factors and Cytokines

Evidence suggests that some systemic and local factors, including cytokines and growth factors in patients with traumatic brain injury (TBI), can play an essential role in accelerating fracture healing. The purpose of this study was to evaluate serum levels of some inflammatory cytokines and growth factors in patients with fracture and TBI as well as healthy subjects. In this study, a total number of 30 patients with a femoral fracture, 30 cases with TBI, 30 patients with TBI and a femoral fracture (fracture + TBI group), and 30 healthy subjects were recruited. The Glasgow Coma Scale (GCS) scores were also determined upon their admission. Then, the serum levels of fibroblast growth factor 2 (FGF-2), transforming growth factor-beta (TGF-β), platelet-derived growth factor (PDGF), bone morphogenetic protein 2 (BMP-2), insulin-like growth factor 1 (IGF-1), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6) were measured via enzyme-linked immunosorbent assay (ELISA) technique, 12 h and 4 weeks after injury and hospital admission. The study results demonstrated that the serum levels of BMP-2, FGF-2, IL-1β, and PDGF in the femoral fracture + TBI group increased significantly over 12 h and after 4 weeks compared with other groups, but the serum levels of IGF-I, IL-6, and TGF-β in this group increased in a significant manner at 12 h compared with other studied groups. The findings also showed that the time to union of a femoral fracture was shorter in the fracture + TBI group than in cases with a femoral fracture alone (p = 0.03). Accordingly, it seems that elevated serum levels of BMP-2, PDGF, FGF-2, and IL-1β may be associated with healing acceleration in fracture + TBI patients. However, further studies are needed to confirm this claim.

The effect of platelet-rich plasma on fracture healing in long-bone pseudoarthrosis

PURPOSE

The aim of this study was to investigate the effects of platelet-rich plasma (PRP) on fracture union rate and fracture union time in pseudoarthrosis surgery and to evaluate the clinical and functional results of the patients.

METHODS

The patients who were undergone pseudoarthrosis surgery between 2011 and 2014 were evaluated retrospectively. Twenty-four patients were included in the study. Patients were divided into two groups with used PRP and not used PRP during surgery. There were 14 patients in the PRP group and 10 patients in the control group. The two groups were compared in terms of demographic characteristics, fracture union time, and functional scores of the Lower Extremity Functional Scale and Upper Extremity Functional Index.

RESULTS

Fractures were healed in both groups, and no complications were encountered. A statistically significant difference was found between the two groups in terms of fracture union time. The mean time of union was 5.3 months in the PRP group and 11.3 months in the control group (p: 0.000). There was no statistically significant difference between the two groups in terms of functional scores (p: 0.250).

CONCLUSION

As a result of our study, we concluded that PRP is an effective and safe method in pseudoarthrosis surgery that reduces fracture union time. Controlled studies with more patient numbers are needed.

Intramedullary nailing for treatment of forearm non-union: Is it useful? - A case series

INTRODUCTION

Intramedullary osteosynthesis is often considered a second-order method for treatment of forearm non-union.

METHODS

We evaluated clinical and functional results from 49 patients affected by radio and/or ulna non-union treated using intramedullary nailing, with possible tricortical autologous bone grafting. Healing rate (primary outcome), healing time and functional status have been assessed.

RESULTS

Healing was observed in 46 cases (93.9%), the average healing time was 6.3 (SD ± 2.5) months. Excellent result (Anderson score) was reached in 38 cases (77.6%), satisfactory in 7 cases (14.3%).

CONCLUSIONS

Forearm non-unions represent a therapeutic challenge. Intramedullary nailing is a successful option of treatment.

Early Radiographic Union Score for Hip Is Predictive of Femoral Neck Fracture Complications Within 2 Years

OBJECTIVES

To determine if the Radiographic Union Score for Hip (RUSH) measured at 3 and 6 months after femoral neck fracture were predictive of reoperation for infection, nonunion, delayed union, avascular necrosis, or implant failure within 24 months of initial surgery.

DESIGN

Secondary analysis of a randomized controlled trial. Logistic regression was performed to investigate associations between lower RUSH and reoperation. Results were reported as odds ratios (OR), 95% confidence intervals (CIs), and associated P values. All tests were 2 tailed with alpha = 0.05.

SETTING

Eighty-one clinical sites across 8 countries.

PATIENTS/PARTICIPANTS

Data from 734 of the clinical trial participants with radiographs at 3 and 6 months after fracture fixation were included.

INTERVENTION

A reviewer blinded to patients' outcomes independently assigned a RUSH at each follow-up time point.

MAIN OUTCOME MEASURES

Revision surgery rate related to intervention.

RESULTS

Lower RUSH at 3 and 6 months were associated with increased odds of reoperation within 24 months of fracture fixation. For every 2-point decrease in RUSH at 3 months, there was a 16% increase in the odds of a patient experiencing a re-operation (OR, 1.16; 95% CI, 1.10-1.22; P < 0.0001). A similar association was observed at the 6-month assessment for every 2-point decrease (OR = 1.05; 95% CI, 1.01-1.09; P = 0.005).

CONCLUSIONS

Decreased radiographic healing as early as 3 months post fracture fixation is associated with developing patient important femoral neck fracture reoperations. This relationship may guide early treatment decisions, suggesting that 3- and 6-month RUSH are a useful surrogate measure of reoperations within 24 months of fracture fixation.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Intramedullary Nailing Versus External Fixation in the Treatment of Open Tibial Fractures in Tanzania: Results of a Randomized Clinical Trial

BACKGROUND

Open tibial fractures are common injuries in low and middle-income countries, but there is no consensus regarding treatment with intramedullary nailing versus external fixation. The purpose of the present study was to compare the outcomes of initial treatment with intramedullary nailing or external fixation in adults with open tibial fractures.

METHODS

We conducted a randomized clinical trial (RCT) at a tertiary orthopaedic center in Tanzania. Adults with acute diaphyseal open tibial fractures were randomly assigned to statically locked, hand-reamed intramedullary nailing or uniplanar external fixation. The primary outcome was death or reoperation for the treatment of deep infection, nonunion, or malalignment. Secondary outcomes included quality of life as measured with the EuroQol-5 Dimensions (EQ-5D) questionnaire, radiographic alignment, and healing as measured with the modified Radiographic Union Scale for Tibial fractures (mRUST).

RESULTS

Of the 240 patients who were enrolled, 221 (92.1%) (including 111 managed with intramedullary nailing and 110 managed with external fixation) completed 1-year follow-up. There were 44 primary outcome events (with rates of 18.0% and 21.9% in the intramedullary nailing and external fixation groups, respectively) (relative risk [RR] = 0.83 [95% confidence interval (CI), 0.49 to 1.41]; p = 0.505). There was no significant difference between the groups in terms of the rate of deep infection. Intramedullary nailing was associated with a lower risk of coronal malalignment (RR = 0.11 [95% CI, 0.01 to 0.85]; p = 0.01) and sagittal malalignment (RR = 0.17 [95% CI, 0.02 to 1.35]; p = 0.065) at 1 year. The EQ-5D index favored intramedullary nailing at 6 weeks (mean difference [MD] = 0.07 [95% CI = 0.03 to 0.11]; p < 0.001), but this difference dissipated by 1 year. Radiographic healing (mRUST) favored intramedullary nailing at 6 weeks (MD = 1.2 [95% CI = 0.4 to 2.0]; p = 0.005), 12 weeks (MD = 1.0 [95% CI = 0.3 to 1.7]; p = 0.005), and 1 year (MD = 0.8 [95% CI = 0.2 to 1.5]; p = 0.013).

CONCLUSIONS

To our knowledge, the present study is the first RCT assessing intramedullary nailing versus external fixation for the treatment of open tibial fractures in sub-Saharan Africa. Differences in primary events were not detected, and only coronal alignment significantly favored the use of intramedullary nailing.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Radiographic evaluations: Which are most effective to follow fracture healing?

The assessment of fracture healing is an imperative and fundamental clinical aspect within orthopaedics. Despite that, there have historically been non-reliable methods utilized to assess for fracture union and nonunion. In recent years, a number of radiographic assessment tools such as the Radiographic Union Score for Tibial fractures (RUST) and Radiographic Union Score for Hip fracture (RUSH) have been developed in order to improve the reliability of fracture assessment for union. These scores have not only increased the reliability of assessments but have also provided thresholds to aid in predicting nonunion as well as union. The nonunion risk determination (NURD) Score was also created to prognosticate these clinical presentations. With the large burdens of cost, lower quality of life and morbidity associated with fracture nonunion, these evaluation methods have provided orthopaedic surgeons with an improved ability to predict nonunion and assist in the management of patients. This review outlines the development, reliability testing as well as biomechanical validity testing associated with these scoring systems.

Validation of a long bone fracture non-union healing score after treatment with mesenchymal stromal cells combined to biomaterials

The available scores to clinically evaluate fracture consolidation encounter difficulties to interpret progression towards consolidation in long-bone non-union, particularly when incorporating biomaterials in the surgical treatment. The aims of this study were to validate the REBORNE bone healing scale in tibia, humerus and femur non-unions treated by a combination of mesenchymal stromal cells (MSCs) and biomaterials, through the interclass correlation (ICC) among raters, and to define reliability and concordance in anteroposterior and lateral radiographs, compared to computed tomography (CT).

METHODS

Twenty-six cases from the EudraCT 2011-005441-13 clinical trial underwent bone healing evaluation, if at least 3 out of 4 cortical views clearly identified. Three senior orthopaedic surgeons evaluated radiographs and CTs at 3 and 6 months FU. All cases included preoperative imaging and radiographs at 12 months. The 4-stage scale score was obtained from each cortical view in orthogonal radiographs or CTs. A score of 0.6875 (11/16) was set as a threshold for bone healing. Statistically, ICC evaluated agreement among raters. Cronbach's alpha coefficient tested reliability. Lin's concordance correlation coefficients (CCC) were estimated between mean CT scores and mean radiographic scores. Bland and Altman graphs provided the limits of agreement between both imaging techniques. Sensitivity and specificity were assessed in radiographs (against CT), and the Area Under the Receiver Operating Characteristics (ROC) Curve was estimated. The probability to predict bone consolidation with REBORNE scores obtained from radiographs was modelled.

RESULTS

An ICC of 0.88 and 0.91 (CT and radiographs) confirmed agreement in the REBORNE score for non-union bone healing, with an inter-rater reliability of 0.92 and 0.95. Scores through the radiographic evaluation were found equivalent to the CTs at 6 months FU. A CCC of 0.79 was detected against CT. The radiographic scores in the REBORNE bone healing scale correctly classified bone consolidation in 77%, with an accuracy of 83% based on ROC curves.

CONCLUSIONS

The REBORNE score measured with CT or radiographic images was reliable among raters at a follow-up time above 6 months for long bone non-union fractures. The REBORNE scale measured with radiographs proved valid to assess consolidation against CT measurements.

Fracture union rates across a century of war: a systematic review of the literature

INTRODUCTION

Fractures have been a common denominator of the injury patterns observed over the past century of warfare. The fractures typified by the blast and ballistic injuries of war lead to high rates of bone loss, soft tissue injury and infection, greatly increasing the likelihood of non-union. Despite this, no reliable treatment strategy for non-union exists. This literature review aims to explore the rates of non-union across a century of conflict, in order to determine whether our ability to heal the fractures of war has improved.

METHODS

A systematic review of the literature was conducted, evaluating the rates of union in fractures sustained in a combat environment over a 100-year period. Only those fractures sustained through a ballistic or blast mechanism were included. The review was in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Quality and bias assessment was also undertaken.

RESULTS

Thirty studies met the inclusion criteria, with a total of 3232 fractures described across 15 different conflicts from the period 1919-2019. Male subjects made up 96% of cases, and tibial fractures predominated (39%). The lowest fracture union rate observed in a series was 50%. Linear regression analysis demonstrated that increasing years had no statistically significant impact on union rate.

CONCLUSIONS

Failure to improve fracture union rates is likely a result of numerous factors, including greater use of blast weaponry and better survivability of casualties. Finding novel strategies to promote fracture healing is a key defence research priority in order to improve the rates of fractures sustained in a combat environment.

Biomechanics of callus in the bone healing process, determined by specimen-specific finite element analysis

As fractures heal, immature callus formed in the hematoma is calcified by osteoblasts and altered to mature bone. Although the bone strength in the fracture-healing process cannot be objectively measured in clinical settings, bone strength can be predicted by specimen-specific finite element modeling (FEM) of quantitative computed tomography (qCT) scans. FEM predictions of callus strength would enable an objective treatment plan. The present study establishes an equation that converts material properties to bone density and proposes a specimen-specific FEM. In 10 male New Zealand white rabbits, a 10-mm long bone defect was created in the center of the femur and fixed by an external fixator. The callus formed in the defect was extracted after 3-6 weeks, and formed into a (5 × 5 × 5 mm³) cube. The bone density measured by qCT was related to the Young's modulus and the yield stress measured with a mechanical tester. For validation, a 10-mm long bone defect was created in the central femurs of another six New Zealand white rabbits, and fixed by an external fixator. At 3, 4, and 5 weeks, the femur was removed and subjected to Computed tomography (CT) scanning and mechanical testing. A specimen-specific finite element model was created from the CT data. Finally, the bone strength was measured and compared with the experimental value. The bone mineral density σ was significantly and nonlinearly correlated with both the Young's modulus E and the yield stress σ. The material-property conversion equations were E = 0.2391e^8.00ρ and ρ = 30.49σ^2.41. Moreover, the experimental bone strength was significantly linearly correlated with the prospective FEM. We demonstrated the Young's moduli and yield stresses for different bone densities, enabling a FEM of the bone-healing process. An FEM based on these material properties is expected to yield objective clinical judgment criteria.

The top three unanswered questions in the management of open fractures

Despite improvements in treatment strategies and emphasis on preventative measures, the management of open fractures continues to be a challenging endeavor for orthopaedic surgeons. Deep infections, delayed healing, and nonunion continue to be problematic complications associated with these devastating injuries. There remain many unanswered clinical questions regarding the management of these injuries and how the various aspects of care can be further optimized. There continues to be a paucity of evidence regarding how infection can best be treated and prevented, how to reliability predict bone healing/nonunion, and how bone healing can be best augmented in the setting of open fractures and their potential nonunions. This review aims to assess the current literature on these top unanswered questions and discuss the gaps in evidence that may be filled with future studies.

Interobserver Reliability in Imaging-Based Fracture Union Assessment-Two Systematic Reviews

OBJECTIVES

(A) To investigate the specialty of observers involved in imaging-based assessment of bone fracture union in recent orthopaedic trials and (B) to provide a general overview of observer differences (in terms of interobserver reliability) in radiologic fracture union assessment that have been reported between surgeons and radiologists.

DATA SOURCES

Two separate systematic reviews (A, B) of English-, German-, and French-language articles in MEDLINE and Embase databases using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were done, with the following time frames: (A) January 2016-August 2017 and (B) through November 2017.

STUDY SELECTION

(A) Clinical trials of surgical fracture treatment evaluating radiologic (non) union. (B) Interobserver studies reporting kappa-values or intraclass correlation coefficients as reliability coefficient for radiologic fracture union assessment. Inclusion criteria for both reviews were fractures of the appendicular skeleton and the use of radiographs or computed tomography.

DATA EXTRACTION

Data were independently retrieved by 2 reviewers.

DATA SYNTHESIS

Descriptive statistics and percentages were reported.

RESULTS

(A) Forty-eight trials were included, whereof 33 (68%) did not report the observer's specialty. Six trials (13%) reported surgeon observers only, and 6 (13%) reported radiologist observers only. The median number of observers is 1 (interquartile range, 1-2). (B) Thirty-one interobserver studies were included, whereof 11 (35%) included at least 1 surgeon and 1 radiologist. Interobserver reliability varied considerably across the various fracture types studied and outcome scale used and was often unsatisfactory (kappa or intraclass correlation coefficients of <0.7).

CONCLUSIONS

In most trials providing observer's characteristics, radiologic fracture union was either rated by 1 surgeon or 1 radiologist. As interobserver reliability can be unsatisfactory, we recommend surgeons and radiologists to further intensify collaboration and trials to include at least 2 observers and associated reliability statistics.

The Radiographic Union Score for HUmeral fractures (RUSHU) predicts humeral shaft nonunion

AIMS

The primary aim of this study was to develop a reliable, effective radiological score to assess the healing of humeral shaft fractures, the Radiographic Union Score for HUmeral fractures (RUSHU). The secondary aim was to assess whether the six-week RUSHU was predictive of nonunion at six months after the injury.

PATIENTS AND METHODS

Initially, 20 patients with radiographs six weeks following a humeral shaft fracture were selected at random from a trauma database and scored by three observers, based on the Radiographic Union Scale for Tibial fractures system. After refinement of the RUSHU criteria, a second group of 60 patients with radiographs six weeks after injury, 40 with fractures that united and 20 with fractures that developed nonunion, were scored by two blinded observers.

RESULTS

After refinement, the interobserver intraclass correlation coefficient (ICC) was 0.79 (95% confidence interval (CI) 0.67 to 0.87), indicating substantial agreement. At six weeks after injury, patients whose fractures united had a significantly higher median score than those who developed nonunion (10 vs 7; p < 0.001). A receiver operating characteristic curve determined that a RUSHU cut-off of < 8 was predictive of nonunion (area under the curve = 0.84, 95% CI 0.74 to 0.94). The sensitivity was 75% and specificity 80% with a positive predictive value (PPV) of 65% and a negative predictive value of 86%. Patients with a RUSHU < 8 (n = 23) were more likely to develop nonunion than those with a RUSHU ≥ 8 (n = 37, odds ratio 12.0, 95% CI 3.4 to 42.9). Based on a PPV of 65%, if all patients with a RUSHU < 8 underwent fixation, the number of procedures needed to avoid one nonunion would be 1.5.

CONCLUSION

The RUSHU is reliable and effective in identifying patients at risk of nonunion of a humeral shaft fracture at six weeks after injury. This tool requires external validation but could potentially reduce the morbidity associated with delayed treatment of an established nonunion. Cite this article: Bone Joint J 2019;101-B:1300-1306.

Utilizing Multiple BioMEMS Sensors to Monitor Orthopaedic Strain and Predict Bone Fracture Healing

Current diagnostic modalities, such as radiographs or computed tomography, exhibit limited ability to predict the outcome of bone fracture healing. Failed fracture healing after orthopaedic surgical treatments are typically treated by secondary surgery; however, the negative correlation of time between primary and secondary surgeries with resultant health outcome and medical cost accumulation drives the need for improved diagnostic tools. This study describes the simultaneous use of multiple (n = 5) implantable flexible substrate wireless microelectromechanical (fsBioMEMS) sensors adhered to an intramedullary nail (IMN) to quantify the biomechanical environment along the length of fracture fixation hardware during simulated healing in ex vivo ovine tibiae. This study further describes the development of an antenna array for interrogation of five fsBioMEMS sensors simultaneously, and quantifies the ability of these sensors to transmit signal through overlaying soft tissues. The ex vivo data indicated significant differences associated with sensor location on the IMN (p < 0.01) and fracture state (p < 0.01). These data indicate that the fsBioMEMS sensor can serve as a tool to diagnose the current state of fracture healing, and further supports the use of the fsBioMEMS as a means to predict fracture healing due to the known existence of latency between changes in fracture site material properties and radiographic changes. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1873-1880, 2019.

Leeds-Genoa Non-Union Index: a clinical tool for asessing the need for early intervention after long bone fracture fixation

AIM OF THE STUDY

The aim of this case-control study was to develop a clinical decision rule to support assessment of the risk of long-bone non-union and plan for appropriate early intervention.

METHODS

Two hundred patients (100 cases and 100 controls) were recruited. Risk factors identified to contribute to the development of non-union were recorded and analysed with a multivariable logistic regression model. Tabulation of the outcome (non-union/union) against each risk factor in turn (univariable analysis) was carried out. Odds ratios and confidence intervals were derived using Wald's method. A receiver-operator curve was calculated and the area under the curve was computed. Having established the eight most important risk factors, a non-union risk index was developed as the count of the risk factors present in each patient.

RESULTS

The five risk factors for non-union with greater effect size were post-surgical fracture gap > 4 mm (odds ratio (OR) = 11.97 95% CI (4.27, 33.53)), infection superficial/deep (OR 10.16 (2.44, 42.36)), not optimum mechanical stability (OR 10.06 (3.75, 26.97)), displacement > 75% of shaft width (OR 6.81 (2.21, 20.95)), and site of fracture-tibia (OR 4.33 (1.32, 14.14)). The ROC curve for the non-union index was 0.924, sensitivity 91%, specificity 77%.

CONCLUSIONS

The non-union index derived from counting risk factors predicts union for 0-4 risk factors and non-union for 5-8 risk factors. It can be readily applied and can guide clinicians about the risk of development of long-bone non-union. It can become a powerful aid for assessing fracture fixation outcome and to support early intervention.

Early return to sport post maxillofacial fracture injury in the professional athlete: A systematic review

INTRODUCTION

To summarize the current literature on return to sport times post-maxillofacial fracture injury in the professional athlete.

MATERIALS AND METHODS

A literature search on six databases for articles relating to maxillofacial fractures, professional athletes, and return to sport times. Study design, clinical data, and author recommendations were analysed.

RESULTS

17 studies were retrieved. One prospective study returned 17 athletes to competitive rugby union and soccer at 3 weeks post injury without complication. Two large retrospective studies (n = 278) returned patients to sport at approximately 7 weeks without complication. 64% (n = 7) of patients from case based studies returned to sport at 3-14 days, 4 of which utilized protective facemasks. Athletes generally returned to competition earlier for lower grade (3-10 days) compared to higher grade contact sport (21 days at least). 2 articles recommended a 3 months recovery period for combat sports. 8 articles supported the utility of protective facemasks.

CONCLUSION

Early return to sport (<6 weeks) in the professional athlete post maxillofacial fracture injury is achievable. The optimal clinical approach may be to grade the sport according to its impact forces, discuss an early return with reference to the available literature, the potential utility of facemasks, risks of refracture and its operative implications.

Semi-quantitative CT assessment of fracture healing: How many and which CT reformats should be analyzed?

PURPOSE

To assess how many and which CT reformats of long bone non-unions should be analyzed to best approximate the analysis of a larger number of CT reformats obtained in the three orthogonal planes.

METHOD

We used 29 CT examinations of tibial or femoral non-unions to obtain 87 stacks of 7 CT reformats each in the coronal (n = 29), sagittal (n = 29) or transverse (n = 29) planes. Two independent radiologists scored two fracture sites on each CT reformat by using a Tomographic Union Score (TUS) (1: no callus, 2: non-bridging callus; 3: bridging immature callus; 4: bridging remodeled callus). The reference standard was the mean of the three TUS calculated from the cortical scores obtained on all the sagittal, coronal and transverse CT reformats. We determined the agreement (intra-class correlation coefficient (ICC) between the reference standard and 33 models combining one to seven CT reformats from one to three planes. The three best models were compared following a resampling procedure by a Wilcoxon's signed rank test.

RESULTS

Three models combining two (mid-coronal and mid-sagittal), three (mid-coronal, mid-sagittal and mid-transverse) or four (two paramedian coronal and sagittal) CT reformats had the highest ICC (ICC ≥ 0.89) for both observers. After resampling, the model combining the two paramedian sagittal and coronal CT reformats statistically outperformed the two other models.

CONCLUSION

Semi-quantitative analysis of the two paramedian sagittal and coronal CT reformats is an acceptable alternative to the analysis of more numerous reformats.

Virtual Mechanical Testing Based on Low-Dose Computed Tomography Scans for Tibial Fracture: A Pilot Study of Prediction of Time to Union and Comparison with Subjective Outcomes Scoring

BACKGROUND

Quantitative outcomes assessment remains a persistent challenge in orthopaedic trauma. Although patient-reported outcome measures (PROMs) and radiographic assessments such as Radiographic Union Scale for Tibial Fractures (RUST) scores are frequently used, very little evidence has been presented to support their validity for measuring structural bone formation or biomechanical integrity.

METHODS

In this pilot study, a sequential cohort of patients with a tibial shaft fracture were prospectively recruited for observation following standard reamed intramedullary nailing in a level-I trauma center. Follow-up at 6, 12, 18, and 24 weeks included radiographs and completion of PROMs (EuroQol 5-Dimension [EQ-5D] and pain scores). Low-dose computed tomography (CT) scans were also performed at 12 weeks. Scans were reconstructed in 3 dimensions (3D) and subjected to virtual mechanical testing via the finite element method to assess torsional rigidity in the fractured limb relative to that in the intact bone.

RESULTS

Patients reported progressive longitudinal improvement in mobility, self-care, activity, and health over time, but the PROMs were not correlated with structural bone healing. RUST scoring showed moderate intrarater agreement (intraclass coefficient [ICC] = 0.727), but the scores at 12 weeks were not correlated with the time to union (R = 0.104, p = 0.193) and were only moderately correlated with callus structural integrity (R = 0.347, p = 0.010). In contrast, patient-specific virtual torsional rigidity (VTR) was significantly correlated with the time to union (R = 0.383, p = 0.005) and clearly differentiated 1 case of delayed union (VTR = 10%, union at 36 weeks) from the cases in the normally healing cohort (VTR > 60%; median union time, 19 weeks) on the basis of CT data alone.

CONCLUSIONS

PROMs provide insight into the natural history of the patient experience after tibial fracture but have limited utility as a measure of structural bone healing. RUST scoring, although reproducible, may not reliably predict time to union. In contrast, virtual mechanical testing with low-dose CT scans provides a quantitative and objective structural callus assessment that reliably predicts time to union and may enable early diagnosis of compromised healing.

LEVEL OF EVIDENCE

Therapeutic Level IV. Please see Instructions for Authors for a complete description of levels of evidence.

Fracture Non-Union: A Review of Clinical Challenges and Future Research Needs

Non-union of bone following fracture is an orthopaedic condition with a high morbidity and clinical burden. Despite its estimated global prevalence of nine million annually, the limit of bone regeneration therapy still results in patients living with pain, a reduced quality of life and associated psychological, social and financial repercussions. This review provides an overview of the current epidemiological and aetiological data, and highlights where the clinical challenges in treating non-union lie. Current treatment strategies are discussed as well as promising future research foci. Development in biotechnologies to treat non-union provides exciting scope for more effective treatment for this debilitating condition.

Potential Economic Benefits of Limited Clinical and Radiographic Follow-up After Plate Fixation of Midshaft Clavicle Fractures

INTRODUCTION

The role of routine clinical and radiographic follow-up after clavicle fractures are healed was evaluated.

METHODS

A retrospective study performed in two level-1 trauma centers included 246 adults with healed clavicle fractures treated surgically between 2000 and 2013 and at least 24-month follow-up. Based on radiographs, changes in fracture alignment or implant position from union to final follow-up were documented. The average reimbursement for a follow-up clinical visit and a clavicle radiograph was estimated.

RESULTS

Mean time to union and mean time of follow-up were of 4.8 and 31.4 months, respectively. No changes in implant position or fracture alignment occurred after the fracture had healed. The amount reimbursed to our institution for two clinical visits and two clavicle radiographs was approximately $300 to $540.

CONCLUSION

Once clavicle fractures are healed, further radiographic imaging does not provide any notable information. Limiting routine follow-up is safe and could be cost-effective for the healthcare system.

LEVEL OF EVIDENCE

Level-III retrospective cohort study.

Inter-Rater Reliability of the Modified Radiographic Union Score for Diaphyseal Tibial Fractures With Bone Defects

OBJECTIVES

To evaluate inter-rater reliability of the modified Radiographic Union Score for Tibial (mRUST) fractures among patients with open, diaphyseal tibia fractures with a bone defect treated with intramedullary nails (IMNs), plates, or definitive external fixation (ex-fix).

DESIGN

Retrospective cohort study.

SETTING

Fifteen-level one civilian trauma centers; 2 military treatment facilities.

PATIENTS/PARTICIPANTS

Patients ≥18 years old with open, diaphyseal tibia fractures with a bone defect ≥1 cm surgically treated between 2007 and 2012.

INTERVENTION

Three of 6 orthopedic traumatologists reviewed and applied mRUST scoring criteria to radiographs from the last clinical visit within 13 months of injury.

MAIN OUTCOME MEASUREMENTS

Inter-rater reliability was assessed using Krippendorff's alpha (KA) statistic; intraclass correlation coefficient (ICC) is presented for comparison with previous publications.

RESULTS

Two hundred thirteen patients met inclusion criteria including 115 IMNs, 24 plates, 29 ex-fixes, and 45 cases that no longer had instrumentation at evaluation. All reviewers agreed on the pattern of scoreable cortices for 90.4% of IMNs, 88.9% of those without instrumentation, 44.8% of rings, and 20.8% of plates. Thirty-one (15%) cases, primarily plates and ex-fixes, did not contribute to KA and ICC estimates because <2 raters scored all cortices. The overall KA for the 85% that could be analyzed was 0.64 (ICC 0.71). For IMNs, plates, ex-fixes, and no instrumentation, KA (ICC) was 0.65 (0.75), 0.88 (0.90), 0.47 (0.62), and 0.48 (0.57), respectively.

CONCLUSIONS

In tibia fractures with bone defects, the mRUST seems similarly reliable to previous work in patients treated with IMN but is less reliable in those with plates or ex-fixes, or after removal of instrumentation.

Radiographic Healing of Far Cortical Locking Constructs in Distal Femur Fractures: A Comparative Study With Standard Locking Plates

OBJECTIVES

To investigate the radiographic healing of far cortical locking (FCL) construct fixation in distal femur fractures compared with traditional locking plate (LP) constructs.

DESIGN

A retrospective cohort of 143 consecutive patients with 146 distal femur fractures.

SETTING

Level I trauma center.

PATIENTS/PARTICIPANTS

After excluding patients with OTA/AO type B fractures, referred nonunion cases, patients younger than 16 years, and patients with less than 24 weeks of follow-up, 69 patients with 70 total fractures were included for analysis.

INTERVENTION

AP and lateral knee radiographs were blinded to type of screws and individually reviewed by 3 orthopaedic trauma surgeons.

OUTCOME MEASUREMENTS

The modified RUST (mRUST) score was our primary outcome measure. mRUST scores were assigned at 6, 12, and 24 weeks and final follow-up based on AP and lateral radiographs and compared between FCL and LP groups as a tool for evaluating fracture healing. Secondary outcomes compared between FCL and LP included union rate and postoperative complications.

RESULTS

Statistically significant differences in mRUST scores were noted between FCL and LP groups at 6 weeks (P = 0.040), 12 weeks (P = 0.034), 24 weeks (0.044), and final follow-up (P = 0.048). There was no significant difference in union or specific complication rates between the 2 groups. The union rate was 90.5% and 82.1% for the FCL and LP groups, respectively, at final follow-up.

CONCLUSIONS

To our knowledge, this is the first comparative study between FCL and LP constructs. The FCL group was noted to have significantly higher mRUST scores at all periods indicating increased callus formation, but the differences seen were small and there were no differences in healing rates or complications between the 2 groups, thus bringing the clinical benefit of FCL into question. Further prospective study designs are needed to compare FCL with LP constructs and to investigate the role of interfragmentary motion on callus formation in distal femur fractures.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.