Radiologic evaluation of fracture healing

Distal femoral fractures: A comparison between single lateral plate fixation and a combined femoral nail and plate fixation

OBJECTIVES

Distal femoral fractures occur in patients with osteoporotic bone and also as a consequence of high energy trauma. The recognised treatment options include closed or open reduction of the fracture and fixation using a locking plate or a femoral nail. Both these fixation modalities have some drawbacks. There is a risk of metalwork failure with single lateral locking plates and limited distal fixation with intramedullary nails. Since January 2018, we started using augmented fixation of distal femoral fractures using a combination of a retrograde femoral nail and a lateral locking plate. This study compares the outcomes of single lateral femoral plating (SLP) and combined nail-plate fixation (NPF).

METHODS

This is a single centre retrospective case control study including all patients who sustained distal femoral fractures (OTA 33-A2, 33-A3, 33-C, 33-V3B and 33-V3D) over the study period. Outcomes for SLP were compared to NPF. The principal outcome measure was fracture union. Secondary outcome measures were reoperation rate, mortality and post-operative weight bearing status.

RESULTS

67 distal femoral fractures were included in the study. 19 patients had peri‑prosthetic fractures. 40 were treated by SLP, 27 were managed with NPF.  23 (58%) patients in the SLP group were given instructions to non-weight bear or Toe touch weight bear for 6 weeks post-surgery compared to 1 (4%) in the NPF group (p = 0.000004). 7 (18%) patients treated with SLP had metalwork failure due to a non-union compared to none treated with NPF (p = 0.04). 11 fractures in the SLP group failed to unite compared to no non-unions in the NPF group (p = 0.01). These differences were magnified when assessing older (>50 years old) patients.

CONCLUSIONS

Augmented fixation of distal femoral fractures using a nail plate fixation provided significantly higher union and enabled early weightbearing compared to single plate fixation. We recommend nail plate fixation for the treatment of distal femoral fractures, particularly in osteoporotic fractures.

One‐Stage Closed Intramedullary Nailing for Delayed Femoral Fracture in Multiple Injured Patients

Objective

To tackle the challengeable dilemma of delayed femoral fracture, a technique of fixator‐assisted closed reduction and intramedullary nailing at one stage was introduced herein and its clinical results were investigated.

Methods

A retrospective study was conducted on delayed femoral shaft fracture between February 2008 and January 2017. The multiple injured patients aged from 18 to 60 years with delayed femoral fracture was included. All patients were treated by one‐stage internal fixation technique and followed up for more than 1 year. Outcome measures including the operation time, intraoperative blood loss and limb alignment, healing time of fracture, visual analog scale (VAS), and range of knee motion were recorded and evaluated.

Results

A total of 13 patients (16 sides) with a mean injury severity score (ISS) of 32.77 ± 9.98 (range, 19 to 52) participated in the investigation. The median length of time‐after‐fracture was 38 days (range, 21 to 110 days). The average shortening distance of the fracture ends was 35.48 ± 19.24 mm (range, 10.00 to 79.00 mm). The average surgery time was 192.19 ± 29.38 min for unilateral femoral fracture, with blood loss of 587.50 ± 232.02 ml. The postoperative discrepancy of lower limb was 3.87 ± 2.52 mm. No patient had vascular and neurologic complications due to the lengthening. All fractures healed successfully with a mean time of 2.98 ± 0.57 months. The mean VAS and maximal knee flexion were 1.63 ± 1.09 and 131.25° ± 5.32° at final follow‐up, respectively.

Conclusions

Our findings indicated that fixator‐assisted closed reduction and intramedullary nailing at one stage is an effective treatment for delayed femoral fracture with satisfactory functional recovery.

Teriparatide and pelvic fracture healing: a phase 2 randomized controlled trial

Pelvic fracture patients were randomized to blinded daily subcutaneous teriparatide (TPTD) or placebo to assess healing and functional outcomes over 3 months. With TPTD, there was no evidence of improved healing by CT or pain reduction; however, physical performance improved with TPTD but not placebo (group difference p < 0.03).

INTRODUCTION

To determine if teriparatide (20 μg/day; TPTD) results in improved radiologic healing, reduced pain, and improved functional outcome vs placebo over 3 months in pelvic fracture patients.

METHODS

This randomized, placebo-controlled study enrolled 35 patients (women and men >50 years old) within 4 weeks of pelvic fracture and evaluated the effect of blinded TPTD vs placebo over 3 months on fracture healing. Fracture healing from CT images at 0 and 3 months was assessed as cortical bridging using a 5-point scale. The numeric rating scale (NRS) for pain was administered monthly. Physical performance was assessed monthly by Continuous Summary Physical Performance Score (based on 4 m walk speed, timed repeated chair stands, and balance) and the Timed Up and Go (TUG) test.

RESULTS

The mean age was 82, and >80% were female. The intention to treat analysis showed no group difference in cortical bridging score, and 50% of fractures in TPTD-treated and 53% of fractures in placebo-treated patients were healed at 3 months, unchanged after adjustment for age, sacral fracture, and fracture displacement. Median pain score dropped significantly in both groups with no group differences. Both CSPPS and TUG improved in the teriparatide group, whereas there was no improvement in the placebo group (group difference p < 0.03 for CSPPS at 2 and 3 months).

CONCLUSION

In this small randomized, blinded study, there was no improvement in radiographic healing (CT at 3 months) or pain with TPTD vs placebo; however, there was improved physical performance in TPTD-treated subjects that was not evident in the placebo group.

A pilot study of circulating levels of TGF-β1 and TGF-β2 as biomarkers of bone healing in patients with non-hypertrophic pseudoarthrosis of long bones

Background

Pseudoarthrosis or non-union is a complication with an incidence of 5-10% of bone fractures, most frequently located in the diaphysis of long bones. The management of this complication is addressed by means of complex surgical procedures and is a concern for orthopaedic and trauma surgeons nowadays. The use of biomarkers for diagnosing patients at risk of non-union would help us to establish special measures for early corrective treatment.

Methods

Prospective exploratory pilot study with a cohort of 20 patients diagnosed of non-hypertrophic pseudoarthrosis of long bones who were treated surgically with either autologous bone graft or a Tissue Engineering Product composed of bone marrow-derived Mesenchymal Stromal Cells. Patients were followed for 12 months and plasma blood samples were obtained to determine circulating levels of Transforming Growth Factor Beta 1 and Beta 2 (TGF-β1 and TGF-β2, respectively) at inclusion, and at 1 week, 2 weeks, and months 1, 2, 3, 6 and 12 after surgery. Radiological bone healing was evaluated by the Tomographic Union Score (TUS).

Results

Basal levels of TGF-β1 and TGF-β2 were determined in the twenty patients (26,702 ± 14,537 pg/mL and 307.8 ± 83.1 pg/mL, respectively). Three of them withdrew from the study, so complete follow-up was conducted on 17 patients (9 successfully healed vs. 8 that did not heal). Statistically significant differences between the bone healing group and the non-union group were found at month 12 for both TGF-β1 (p = 0.005) and TGF-β2 (p = 0.02).

Conclusions

TGF-β1 and TGF-β2 are biomarkers that correlate with clinical evidence of bone regeneration and may be used to monitor patients, although early predictive value after intervention needs to be further studied in combination with other molecules.

The role of low-grade infection in the pathogenesis of apparently aseptic tibial shaft nonunion

PURPOSE

Aim of this study was to determine the rate of low-grade infection in patients with primarily as aseptic categorized tibial shaft nonunion and lack of clinical signs of infection.

METHODS

In a retrospective study between 2006 and 2013, all patients who underwent revision surgery for treatment of tibial shaft nonunion without clinical evidence of infection were assessed. Bacterial cultures harvested during nonunion revision, C-reactive protein (CRP) and/or white blood cell (WBC) values at hospital admission, outcome, and epidemiological data were analyzed.

RESULTS

In 88 patients with tibial shaft nonunion without any clinical signs of infection, bacterial samples remained negative in 51 patients. In 37 patients, microbiological diagnostic studies after long-term culturing demonstrated positive bacterial cultures whereas after short-term culturing for 2 days only 17 positive cultures were observed. In 12 cases a mixed culture with 2.3 different bacteria on average was detected. Among patients with negative bacterial cultures bone healing was achieved after 13.2 months. Nonunion with positive bacterial cultures required 19 (range 2-42) months until osseous healing (p = 0.009). Furthermore, nonunion with positive bacterial cultures require statistically more surgical revisions to achieve healing (2.9 ± 0.5 vs. 1.3 ± 0.1 additional procedure; (p = 0.003). Hematological studies carried out before surgical intervention did not demonstrate significant differences in CRP values (negative vs. positive cultures: 0.3 (range 0.3-2.8) mg/dl vs. 0.5 (range 0.3-5.7) mg/dl (p = 0.181) and in WBC values (negative vs. positive cultures: 7.4 (range 3.5-11.9) /nl vs. 7.3 (range 3.7-11.1) /nl (p = 0.723). Limitations of this study may include the varying amount of the at least four samples for microbiological diagnostics as well as the circumstance that for diagnosing low-grade infection swabs and tissue samples were included in this evaluation as being equivalent.

CONCLUSION

The pathogenesis of nonunion may originate from low-grade infection even in patients without clinical signs of infection. In addition, nonunion with positive bacterial cultures require statistically more surgical revisions to achieve healing. Therefore, during any revision surgery, multiple bacterial samples are intended to be harvested for long-term culturing. Particularly, in tibial shaft nonunion following Gustilo-Anderson type III open fractures, low-grade infection should be suspected.

TRIAL REGISTRATION NUMBER

DRKS00014657.

DATE OF REGISTRATION

04/26/2018 retrospectively registered.

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.

Pulsed Electromagnetic Fields in Bone Healing: Molecular Pathways and Clinical Applications

In this article, we provide an extensive review of the recent literature of the signaling pathways modulated by Pulsed Electromagnetic Fields (PEMFs) and PEMFs clinical application. A review of the literature was performed on two medical electronic databases (PubMed and Embase) from 3 to 5 March 2021. Three authors performed the evaluation of the studies and the data extraction. All studies for this review were selected following these inclusion criteria: studies written in English, studies available in full text and studies published in peer-reviewed journal. Molecular biology, identifying cell membrane receptors and pathways involved in bone healing, and studying PEMFs target of action are giving a solid basis for clinical applications of PEMFs. However, further biology studies and clinical trials with clear and standardized parameters (intensity, frequency, dose, duration, type of coil) are required to clarify the precise dose-response relationship and to understand the real applications in clinical practice of PEMFs.

Methods to address metal artifacts in post-processed CT images - A do-it-yourself guide for orthopedic surgeons

Computed tomography (CT) scans are often used for postoperative imaging in orthopedics. In the presence of metallic hardware, artifacts are generated, which can hamper visualization of the CT images, and also render the study ineffective for 3-D printing. Various solutions are available to minimize metal artifacts, and radiologists can employ these before or after processing the CT study. However, the orthopedic surgeon may be faced with situations where the metal artifacts were not addressed. To counter such problems, we present three do-it-yourself (DIY) techniques that can be used to manage metal artifacts.

Classification of femur trochanteric fracture: Evaluating the reliability of Tang classification

INTRODUCTION

Given the drawbacks of a femoral intertrochanteric fracture classification based on 2-dimensional radiographic imaging, an artificial intelligence-based classification system- the Tang classification system-which uses 3-dimensional image analysis, has previously been developed. This study explored the reliability of the Tang classification by comparing the consistency of this classification with the conventional 2-dimensional femoral intertrochanteric fracture classification systems.

METHODS

X-ray and computed tomography (CT) data of 258 patients with femoral intertrochanteric fractures were classified by 6 orthopedic surgeons using the Evans, Jensen, AO/OTA, and Tang classification systems on 2 separate occasions, 1 month apart. Kappa statistics were used to evaluate the inter- and intraobserver differences in classifications.

RESULTS

When the interobserver reliability was based on X-ray image analysis, the Kappa values for the Evans, Jensen, AO/OTA, and Tang classifications were 0.54 ± 0.03 (moderate agreement), 0.53 ± 0.02 (moderate agreement), 0.46 ± 0.02 (moderate agreement), and 0.63 ± 0.02 (substantial agreement), respectively. When the interobserver reliability was based on CT images, the Kappa values of the Evans, Jensen, AO/OTA, and Tang classifications were 0.49 ± 0.03 (moderate agreement), 0.49 ± 0.03 (moderate agreement), 0.44 ± 0.03 (moderate agreement), 0.64 ± 0.02 (substantial agreement), respectively. For X-ray images, the intraobserver Kappa values for the Evans, Jensen, AO/OTA, and Tang classification were 0.53 ± 0.02 (moderate agreement), 0.54 ± 0.03 (moderate agreement), 0.45 ± 0.03 (moderate agreement), and 0.65 ± 0.03 (substantial agreement), respectively. When intraobserver reliability was based on CT images, the Kappa values for the Evans, Jensen, AO/OTA, and Tang classification were 0.52 ± 0.03 (moderate agreement), 0.52 ± 0.02 (moderate agreement), 0.41 ± 0.02 (moderate agreement), and 0.63 ± 0.03(substantial agreement), respectively.

CONCLUSIONS

The current study suggests that the Tang classification system is more reliable than the Evans, Jensen, and AO/OTA classification systems for measuring intertrochanteric fractures of the proximal femur.

Comparison of surgical outcomes between single versus dual K-wire fixation for unstable distal phalanx fractures

Distal phalanx fractures are the most common injuries of the hand, and K-wire fixation is commonly performed for unstable fractures. However, there is no consensus regarding the number of K-wires to use in bone fixation. We aimed to compare the results between single and dual K-wire pinning. This retrospective study enrolled patients who underwent K-wire pinning for unstable distal phalanx fractures, including the shaft and tuft, from June 2016 through April 2020. We divided patients into two groups based on the number of K-wires used for bone fixation (single vs. dual). Clinical and radiographic data were measured and compared between the two groups. Additionally, multivariable logistic analysis was performed to identify the risk factors for nonunion. A total of 80 patients were enrolled. Among them, 27 were managed with a single K-wire and 53 with a dual K-wire. There was no significant difference in the union rate between the single and dual K-wire groups (77.7% vs. 84.9%, respectively), but time to union was significantly longer in the single K-wire group (11.3 vs. 8.4 weeks; p = .003). The presence of a bone gap after fixation was a risk factor for nonunion. Our study showed that the union rate was comparable between single and dual K-wire pinning in distal phalanx fractures. However, dual K-wire pinning shortened the union time.

Medium term outcome of Lancaster cortical window technique for extraction of femoral stem in revision hip arthroplasty

Background

The extraction of a femoral stem during the revision hip arthroplasty can be a daunting task and can lead to catastrophic complications for the patient. A sound technique employed intraoperatively helps in the speedy recovery of the patient and reduces the risk of future surgical interventions. In this study, we present a medium-term outcome of our novel Lancaster cortical window technique which can be used for the removal of cemented or uncemented femoral stems.

Methods

The study was conducted at a specialist centre in the north-west of the UK from January 2014 to May 2019. This is a retrospective case series where patients were treated surgically using the Lancaster cortical window technique for removal of the femoral implant during a revision hip arthroplasty. Patient’s electronic notes and radiographs were used to evaluate the functional and radiological outcome.

Results

In this study, 18 patients were managed surgically using the novel Lancaster window technique. The mean age of all the patients was 81.5 years, and the male to female ratio was 10:8. Fifteen patients underwent revision surgery for aseptic loosening of the femoral and acetabular components. The rest of the three patients had revision surgery for a broken femoral stem, intraoperative femoral canal perforation while implanting a total hip replacement femoral stem and infection. Twelve femurs were replanted with uncemented long femoral stems and six with long cemented stems. The cortical window osteotomy united in all the patients in 4.2 months (mean). The mean follow-up of these patients is 20.9 months, and none of them had any implant subsidence or loosening at the time of their last follow-up.

Conclusion

We believe Lancaster cortical window technique can be safely used for the removal of cemented stems during revision hip arthroplasty without the need for expensive equipment.

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.

Results of revision intramedullary nailing with and without auxillary plate in aseptic trochanteric and subtrochanteric nonunion

PURPOSE

Aim of this study was to investigate whether limited open auxiliary angle stable plate fixation has an effect on functional and radiologic outcomes one year after revision intramedullary nailing in aseptic trochanteric and subtrochanteric fracture nonunion.

METHODS

In a retrospective analysis, surgically revised aseptic trochanteric and subtrochanteric nonunion was evaluated in a total of 190 consecutive patients ranging from 18 to 94 years between 12/2005 and 10/2018.

RESULTS

One year after revision intramedullary nailing, nonunion healing was assessed in 129 out of 136 patients (95%) in group 1 without auxiliary plate fixation and in 51 out of 54 patients (94%) in group 2 with auxiliary plating (p = 0.23). In group 1, range of motion (ROM) was unrestricted in 88 patients and still restricted in 48 patients. In group 2, ROM was free in 34 patients and restricted in 20 patients (p = 0.25). The mean Lower Extremity Functional Scale (LEFS) was 56 points in group 1 and 55 points in group 2 (p = 0.55).

CONCLUSION

This study did not demonstrate significant differences in functional and radiologic outcomes following revision intramedullary nailing of aseptic trochanteric and subtrochanteric fracture nonunion. Limited open auxiliary plate fixation might be a reasonable option especially in cases of relevant varus axis deviation and comminuted or atypical fracture configurations, regardless of patients' age. Retrospectively registered with the German Clinical Trials Register (01/25/2021; ID: DRKS00024112).

The potential of micro-CT for dating post-cranial bone fractures: a macroscopic, radiographic, and microtomography study of fractures of known post-traumatic ages

The estimation of the post-traumatic survival time (PTST) in case of bone injuries remains a tricky issue in the forensic field, especially when dealing with dry bones. Newer high-resolution imaging, and in particular microcomputed tomography (micro-CT), has the potential to significantly improve our abilities to interpret antemortem and perimortem lesions and accurately date fractures in a less destructive analysis. In this paper, nine costal fractures of known post-traumatic ages were analyzed through gross examination, conventional radiography, and microcomputed tomography, in order to test the potential of microcomputed tomography for dating fractures. As a result, microcomputed tomography provided images of high quality and definition and allowed the observation of the internal microarchitecture of the fractures and calluses. While microcomputed tomography cannot substitute histological examination for the estimation of the post-traumatic survival time, it constitutes a potent and helpful complementary tool for the analysis of bone trauma.

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.

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.

Level of osteotomy is relevant to obtain better union and clinical results in patients with severe hip dysplasia operated on with total hip arthroplasty and shortening osteotomy using a cementless, rectangular femoral component

INTRODUCTION AND OBJECTIVE

Total hip arthroplasty with rectangular femoral component and transverse osteotomy for patients with Crowe type 3 or 4 dysplasia yields successful results with varying radiological findings. This study aims to investigate the surgery and patient related factors associated with successful clinical and radiological results.

PATIENTS AND METHODS

Fifty hips of 41 patients were retrospectively examined. Length and percentage of the stem passing the osteotomy level and canal fill ratio were measured. Radiological findings such as radiolucent lines (RL) around the stem, hypertrophic callus or an identifiable osteotomy line on X-ray images were assessed. All clinical and radiological results were analyzed for any significant association.

RESULTS

Mean stem length and percentage passing the osteotomy level were 6.4 cm (± 0.7) and 51% (± 6). Presence of an identifiable osteotomy line was positively associated with the increasing length of the stem passing the osteotomy level and with a lower HHS (p < 0.05). RL around the stem were associated with a lesser reduction in VAS score (p < 0.05).

CONCLUSION

Rectangular femoral stem conveniently accommodate the proximal femur in severely dysplastic hips. An upper limit for the femoral stem exists to obtain better bony union and higher HHS. RL around the stem are clinically relevant and is associated with a worse VAS score at the latest follow-up.

Mechanobiology of Bone Consolidation During Distraction Osteogenesis: Bone Lengthening Vs. Bone Transport

Bone lengthening and bone transport are regeneration processes that commonly rely on distraction osteogenesis, a widely accepted surgical procedure to deal with numerous bony pathologies. Despite the extensive study in the literature of the influence of biomechanical factors, a lack of knowledge about their mechanobiological differences prevents a clinical particularization. Bone lengthening treatments were performed on sheep metatarsus by reproducing the surgical and biomechanical protocol of previous bone transport experiments. Several in vivo monitoring techniques were employed to build an exhaustive comparison: gait analysis, radiographic and CT assessment, force measures through the fixation, or mechanical characterization of the new tissue. A significant initial loss of the bearing capacity, quantified by the ground reaction forces and the limb contact time with the ground, is suffered by the bone lengthening specimens. The potential effects of this anomaly on the musculoskeletal force distribution and the evolution of the bone callus elastic modulus over time are also analyzed. Imaging techniques also seem to reveal lower bone volume in the bone lengthening callus than in the bone transport one, but an equivalent mineralization rate. The simultaneous quantification of biological and mechanical parameters provides valuable information for the daily clinical routine and numerical tools development.

Does auxiliary cerclage wiring provide intrinsic stability in cephalomedullary nailing of trochanteric and subtrochanteric fractures?

Purpose

The aim of this study was to assess functional and radiological results following cephalomedullary nailing with and without use of auxiliary cable cerclages in a large series of trochanteric and subtrochanteric femoral fractures.

Methods

In a retrospective study of prospectively collected data between January 2014 and March 2019, a total of 260 consecutive patients (155 women and 105 men) with the diagnosis of AO/OTA A1 to A3 fractures were included. The mean age of patients was 76.4 ± 15.6 years. According to the AO/OTA classification, 72 A1 fractures, 124 A2 fractures, and 64 A3 fractures were found. In 72 patients with auxiliary cerclage wiring three A1 fractures, 27 A2 fractures and 42 A3 fractures were assessed. In the patient group with auxiliary cerclages, fracture healing according to the Radiographic Union Score for Hip (RUSH) within one year after surgery was assessed in 68 out of 72 patients (healing rate 94%). The mean RUSH in the group with cerclages was 28.7 ± 2.2 points and was 28.5 ± 2.2 points in the group without cerclages (p = 0.72). In 91 patients available for a complete follow-up, mean functional outcome according to the Lower Extremity Functional Scale (LEFS) was 65.3 ± 17.2 points in the group with cerclages versus 58.4 ± 21 points in the group without cerclages (p = 0.04).

Conclusion

The additional use of cerclages provides intrinsic stability and enables axial alignment and medial cortical support during anatomical fracture reduction and cephalomedullary nail insertion. In the current study, this technique resulted in significantly better functional long-term outcomes than without cerclages. Therefore, it can be recommended as a useful supportive tool especially in comminuted trochanteric and subtrochanteric fractures. Trial registration number DRKS00020550, 01/30/2020, retrospectively registered.

Determining diagnosis of scaphoid healing: Comparison of cone beam CT and X-ray after six weeks of immobilization

PURPOSE

To assess the accuracy and reliability of using cone beam computed tomography (CBCT) compared to X-ray six weeks after injury for predicting scaphoid union.

MATERIALS AND METHODS

Overall; 52 patients with scaphoid fractures between April 2018 and March 2019 were prospectively included in this study. The mean age was 34.52 (13-88) years, and the gender ratio male/female 43/9. Of the fractures, 26 had occurred on the right side, and 26 on the left side. In total, 28 % of patients were manual workers. All patients underwent X-ray and CBCT six weeks after injury. Four readers, two radiologists, and two hand surgeons analyzed the findings using double-blinded X-ray and CBCT and categorized fractures as consolidated based on a 50 % visibility threshold concerning trabecular bridges. Proximal pole sclerosis, communition, cyst formation, and humpback deformity were similarly analyzed for all cases. Agreement between readers was calculated using Kappa, and sensitivity, specificity, and accuracy using RStudio software. The gold standard was the radiologic and clinical follow-up for all patients at two months.

RESULTS

Inter-reader agreement between the four readers was moderate concerning X-ray (0.543) but substantial concerning CBCT (0.641). It was almost perfect between seniors regarding CBCT (Kappa = 0.862). Sensitivity, specificity, and accuracy were 0.75-0.78, 0.4, and 0.61-0.64, respectively, for two readers regarding CBCT. The X-ray values were 0.65-0.71, 0.35-0.4, and 0.53-0.59, respectively.

CONCLUSION

CBCT proves more accurate and reliable than X-ray for diagnosing scaphoid union at an early follow-up and prevents longer immobilization and interruption of activity or work.

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.

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.