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Objectives: Osteoporosis is associated with greater risk of fracture, which can lead to increased morbidity and mortality. DEXA scans are often inaccessible for patients, leaving many cases of osteoporosis undetected. A portable 3D topographical scan offers an easily accessible and inexpensive potential adjunct screening tool. We hypothesized that 3D scanning of arm and calf circumference and volume would correlate with DEXA T-scores. Methods: 96 female patients were enrolled. Patients were consented and completed a topographical scan of bilateral arms and lower legs with a mobile 3D scanner for arm and calf circumference and volume in clinic. Patient charts were then retrospectively reviewed for DEXA T-scores. Results: Forearm DEXA T-score was positively correlated with arm circumference (r = 0.49, p<0.01), arm volume (r=0.62, p<0.01), and calf volume (r=0.47, p<0.01). Femoral neck DEXA T-score was positively correlated with calf circumference (r=0.36, p<0.01) and calf volume (r=0.36, p<0.01). Conclusions: Our results showed significant correlations between DEXA T-scores and topographical measurements from mobile device acquired 3D scans, although these were in the "moderate" range. Mobile device-based 3D scanning may hold promise as an adjunct screening tool for osteoporosis when DEXA scanning is not available or feasible for patients, although further studies are needed to elucidate the full potential of its clinical utility. At a minimum, identifying a patient as high risk may promote earlier diagnostic DEXA scanning. [ABSTRACT FROM AUTHOR]

Fracture healing is highly dependent on an early inflammatory response in which prostaglandin production by cyclo-oxygenases (COX) plays a crucial role. Current patient analgesia regimens favor opioids over Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) since the latter have been implicated in delayed fracture healing. While animal studies broadly support a deleterious role of NSAID treatment to bone-regenerative processes, data for human fracture healing remains contradictory. In this study, we prospectively isolated mouse and human skeletal stem cells (SSCs) from fractures and compared the effect of various NSAIDs on their function. We found that osteochondrogenic differentiation of COX2-expressing mouse SSCs was impaired by NSAID treatment. In contrast, human SSCs (hSSC) downregulated COX2 expression during differentiation and showed impaired osteogenic capacity if COX2 was lentivirally overexpressed. Accordingly, short- and long-term treatment of hSSCs with non-selective and selective COX2 inhibitors did not affect colony forming ability, chondrogenic, and osteogenic differentiation potential in vitro. When hSSCs were transplanted ectopically into NSG mice treated with Indomethacin, graft mineralization was unaltered compared to vehicle injected mice. Thus, our results might contribute to understanding species-specific differences in NSAID sensitivity during fracture healing and support emerging clinical data which conflicts with other earlier observations that NSAID administration for post-operative analgesia for treatment of bone fractures are unsafe for patients. [ABSTRACT FROM AUTHOR]

Purpose: Tranexamic acid (TXA) reduces need for transfusion in total joint arthroplasty, though findings in acetabular surgery are conflicting. We compared outcomes after acetabular fracture surgery with or without perioperative intravenous (IV) TXA administration. Methods: We performed a retrospective review of 305 patients with acetabular fractures that underwent open reduction and internal fixation (ORIF). Eighty-nine patients received TXA, and 216 did not. The primary outcome was rates of intraoperative and postoperative allogeneic blood transfusion. Results: Baseline demographics and characteristics were similar. Time from injury to surgery and estimated blood loss were comparable. Operative time (p < 0.01) and intraoperative IV fluids (p < 0.01) were greater in the non-TXA group. The proportion of patients who received blood transfusion and mean units transfused intraoperatively and postoperatively did not differ. Mean differences in preoperative and postoperative hemoglobin and hematocrit, hospital length of stay, and perioperative complications also did not differ. In a multivariable regression model, age 60–70 years, Charlson Comorbidity Index, Injury Severity Score, and fracture patterns likely to bleed were independently associated with intraoperative transfusion. Anterior surgical approaches and intraoperative transfusion requirement were independently associated with postoperative transfusion. Conclusion: In this study, perioperative IV TXA did not decrease blood loss, need for transfusion, or improve in-hospital outcomes of acetabular fracture surgery. Age 60–70, CCI, ISS, and fracture patterns likely to bleed were independently associated with intraoperative transfusion. Anterior surgical approach and need for intraoperative transfusion were independently associated with postoperative transfusion. Further prospective trials are warranted to confirm these findings [ABSTRACT FROM AUTHOR]

Purpose: The primary aim of this study was to compare clinical outcomes in patients with associated both column (ABC) acetabular fractures with fracture of the posterior wall (PW), in which the PW underwent reduction and fragment-specific fixation versus those that were treated with column fixation alone. Secondary aims were to assess PW fracture incidence and morphology, as well as to compare radiographic outcomes including fracture healing and interval displacement of the PW in those that did and did not undergo fragment-specific fixation of the PW. Methods: This was a retrospective series of ABC acetabular fractures treated at a single Level I trauma center. Separate fractures of the PW were identified, and associated features were assessed. Associated both column fractures that underwent reduction and fragment-specific fixation of the PW where then compared to ABC fractures with PW involvement that underwent column reconstruction alone. Radiographic and clinical outcomes were compared. Results: Fractures of the PW occurred in 55.7% of ABC fractures and were associated with central displacement of the femoral head. The majority of PW fractures were large and involved the acetabular roof. All PW fractures healed without displacement by 3 months, regardless of whether or not reduction and stabilization was performed. Mid-term outcomes at 1-year were similar regardless of whether or not the PW was reduced and stabilized, with regards to Tönnis grade, Merle d'Aubigné-Postel score, and conversion to total hip arthroplasty. Conclusion: Reduction and fragment-specific fixation of the PW component of ABC acetabular fractures did not improve outcomes in this small comparative study. Posterior wall fractures associated with ABC patterns are frequently large-sized fragments that involve the acetabular roof and are rendered stable after reconstruction of the columns. [ABSTRACT FROM AUTHOR]

To report mid-term clinical outcomes after radial head arthroplasty for terrible-triad fracture dislocations. Fourteen patients with terrible triad fracture dislocations treated acutely with arthroplasty and minimum 3-year follow-up. Mayo Elbow Performance Scale (MEPS) and QuickDASH scores. All patients achieved excellent (58%) or good (42%) results on the MEPS. Average QuickDASH score was 9.1 (range 0-25). Reoperation rate was 28%. Acute radial head arthroplasty as a treatment for nonreconstructable radial head fractures in the setting of terrible triad elbow injuries demonstrates good midterm functional outcomes. Level IV; Retrospective Case Series Study [ABSTRACT FROM AUTHOR]

Background: The need for coracoclavicular (CC) ligament augmentation when performing locking plate fixation of unstable distal clavicle fractures is controversial. The purpose of this study was to compare the results after locking plate fixation for treatment of Neer type-II and type-V distal clavicle fractures with and without suture suspensory augmentation of the CC ligaments. Methods: This was a retrospective case series of all Neer type-II and type-V distal clavicle fractures treated with locking plates at a single Level I trauma center. Patients were separated into locking plate-only and locking plate with CC ligament augmentation groups. Postoperative complications and fracture healing rates were recorded. Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) scores were recorded as functional outcomes during follow-up phone interviews. Standard descriptive statistics were performed. Results: Sixteen patients were treated with locking plate fixation-only, and seven patients were treated with additional CC ligament augmentation. There was a similar distribution of Neer fracture types with each group. All fractures in both groups went onto union without loss of reduction or implant failure. There were no cases of infection or wound complications in either group. QuickDASH scores were comparable between locking plate-only fixation (mean 4.1 ± 3.9) and additional suspensory suture fixation (mean 4.5 ± 3.6). Conclusion: This comparative study of Neer type-II and type-V distal clavicle fractures demonstrated comparable outcomes after locking plate fixation with and without CC ligament augmentation. CC ligament augmentation may not be necessary when treating unstable distal clavicle fractures if locking plate fixation is used. [ABSTRACT FROM AUTHOR]

Intra-articular screw cut-out is a potential complication of intertrochanteric femur fracture fixation with a cephalomedullary nail. Cement augmentation of fixation in the proximal segment offers the prospect of increased stability and fewer complications, but clinical experience with non-resorbable cement is limited. To determine the handling properties and efficacy of this new technique, we performed a retrospective propensity-matched cohort of forty-four geriatric intertrochanteric femur fractures treated with a cephalomedullary nail with (n = 11) or without (n = 33) augmentation with non-resorbable cement injected into the proximal segment. In the patients treated with cement augmentation, at minimum 3-month follow-up, there were no instances of intra-articular cut-out, and no increase in re-operation compared to conventional fixation. Cement augmentation appears to be safe and effective in geriatric intertrochanteric femur fractures to mitigate risk of cut-out. [ABSTRACT FROM AUTHOR]

Purpose: The optimal management of valgus-impacted femoral neck fractures remains controversial. Internal fixation is associated with significant rates of re-operation, while historical non-operative management strategies consisting of prolonged bed rest also resulted in patient morbidity. Our hypothesis was that screw fixation would have comparable failure rates to non-operative treatment and immediate mobilization for valgus-impacted femoral neck fractures. Methods: Retrospective cohort at a single academic Level I trauma center of patients with valgus-impacted femoral neck fractures (AO/OTA 31-B1) treated with percutaneous screw fixation (n = 97) or non-operatively (n = 28). Operative treatment consisted of percutaneous screw fixation. Non-operative treatment consisted of early mobilization. The primary outcome was a salvage operation. Patient demographics were assessed between groups. Results: More non-operatively treated patients were permitted unrestricted weight-bearing (WBAT; p = 0.002). There was no increase in complication rates or mortality, and return to previous ambulatory status was comparable between operatively and non-operatively treated patients. 35.7% (10/28) of non-operatively treated patients underwent a subsequent operation, compared to 15.5% (15/97) of patients with screw fixation (p = 0.03). Only WBAT was independently associated with treatment failure (OR 3.1, 95%CI 1.2–8.3, p =0.02). WBAT was predictive of treatment failure only in the non-operatively treated group (64.3%, 9/14 WBAT vs 8.3%, 1/12 partial, p =0.005). Conclusion: After controlling for weight-bearing restrictions, we found no difference in failure rates between non-operative treatment and screw fixation. Non-operative treatment with partial weight-bearing had low failure rates, comparable complication and mortality rates, and equivalent functional outcomes to operative treatment and is reasonable if a patient would like to avoid surgery and accepts the risk of subsequent arthroplasty. Overall, there were relatively high failure rates in all groups. [ABSTRACT FROM AUTHOR]

Purpose: This study examined the outcomes and complications after treatment of unstable distal clavicle fractures with hook or locking plate fixation. Methods: A retrospective search was performed of all acute distal clavicle fractures treated with open reduction and internal fixation from 2009 to 2019 at a Level I trauma center. Patients were separated into hook and locking plate fixation groups. Rates of union, complications, and reoperation, were extracted. QuickDASH (Disabilities of Arm, Shoulder, and Hand) scores were determined. Results: Thirty-one patients met the inclusion criteria and were included in the study. Of these, 12 patients were treated with hook plates and 19 were treated with locking plates. All fractures healed without loss of reduction, regardless of implant selection. There were no immediate or long-term complications in either group. 83% of hook plate patients underwent planned implant removal, while 37% of locking plate patients requested implant removal secondary to irritation. QuickDASH scores were comparable and excellent in both groups. Conclusions: Hook and locking plate fixation for Neer type-II and type-V distal clavicle fractures have comparably high rates of union. Hook plates were removed routinely per protocol, while locking plates were removed only if symptomatic and occurred significantly less often. [ABSTRACT FROM AUTHOR]

Dynamization of fracture fixation constructs provides early rigidity for primary bone healing and late motion for secondary healing. A review of laboratory, animal, and clinical studies investigating the impact, and optimal timing, of dynamization is limited by lack of standardization across studies. However, in animal models, dynamization improves histologic and biomechanical properties compared with statically rigid or flexible controls. In animals, dynamization at 3 to 4 weeks showed improved histologic results. In clinical studies, it showed faster, stronger, and stiffer bone healing. Clinical success dynamizing external fixators and intramedullary nails suggests a role for late dynamization in other fixation types, such as bridge plating. [Orthopedics. 2020;43(3):e125-e133.]. [ABSTRACT FROM AUTHOR]

The article focuses on several studies related to orthopaedics. In one study, 300 patients with hip fractures and anemia were compared with patients treated with and without iron supplementation. Another study correlates the degree of symphysis pubis diastasis with the degree of pelvic ligament injury. Another focuses on impact of suprapatellar, semi-extended intramedullary tibial nailing.

Summary: Objectives: Rotational deformity following intramedullary nailing of femoral shaft fractures is a clinically significant and underdiagnosed problem. Intraoperative determination of rotation is difficult and may be caused by several factors. The insertion of interlocking screws at a slightly oblique angle may cause a substantial degree of rotational deformity, and this factor has not been evaluated as a cause of malrotation. Methods: In eight paired cadaveric femurs, a midshaft transverse fracture was created and an antegrade nail was placed. The specimens were placed in a custom jig which allowed free rotation of the distal segment. Distal interlocking was performed using either a freehand technique or with navigation, and femoral anteversion was measured before and after interlocking to determine the change caused by the interlocking screw. Results: Freehand placement led to rotational shift up to 7° (mean, 5.8°; range, 4–7°), and navigated insertion led to a change of 2.0° (range, 1–3°; p <0.05). In addition, drill–nail contact and a visible shift of the fracture site occurred in all freehand trials, whereas in the navigation group, contact occurred in only one trial without fracture movement. Conclusions: Freehand distal interlocking may be a substantial cause of rotational deformity, and the assistance of computer navigation systems may improve this malrotation. [Copyright &y& Elsevier]

Background: Intertrochanteric hip fractures have become more common as the elderly population continues to increase, and surgical stabilisation of these fractures remains a persistent challenge. The purpose of this study was to analyse the ability of a new helical blade device to stabilise intertrochanteric hip fractures, and to further determine which factors are important in implant stability. Methods: Two hundred and fifty-five patients with an intertrochanteric hip fracture were treated with a trochanteric fixation nail (TFN), 97 of whom fit strict radiographic and follow-up criteria and were included in the study group. After adjusting for magnification and rotation, blade migration within the femoral head and telescoping of the blade along its axis were measured using a custom-designed grid system. Multivariate regression analyses were performed to determine which variables predicted blade migration and telescoping. Results: Fifty-nine fractures were classified as stable, and the remaining 38 were unstable. Mean telescoping was 4.3 mm in the unstable group, compared to 2.6 mm in the stable group (p<0.05). Blade migration within the femoral head averaged 2.2 mm overall, with no difference between stable and unstable fractures. For both telescoping and blade migration, no significant change occurred after the 6-week time point in the stable or unstable group. Nail length, age, and gender did not have a significant effect on either blade migration or telescoping implant position change. Of the initial cohort of 255 patients, five cutouts and one nonunion occurred, three of which required subsequent procedures. Conclusions: Subtle migration ( approximately 2mm) of the tip of the blade within the femoral head occurred in all fractures, but this did not preclude maintenance of reduction and fracture healing, and was not predicted by fracture type, reduction quality, age, or gender. More telescoping occurred in unstable compared to stable fractures, but this averaged 4mm and did not affect stable fixation or fracture healing. All position changes occurred within the first 6 weeks postoperatively, with no subsequent detectable migration or telescoping. Clinical correlations will be needed in the future to determine the significance of small amounts of migration or differences in telescoping, but this device appears to provide effective fixation in both stable and unstable intertrochanteric hip fractures. [ABSTRACT FROM AUTHOR]

Background: Vertebral augmentation procedures are currently widely performed to treat vertebral compression fractures. In selecting appropriate patients for these procedures, it is important to distinguish the pain caused by a fracture from other causes of back pain. The purpose of this study was to determine the frequency of underlying, previously unrecognized malignant tumors in a consecutive series of patients undergoing kyphoplasty to treat vertebral compression fractures. Our hypothesis was that an unsuspected malignant tumor will exist and that a bone-marrow aspiration from the iliac crest would enhance our ability to detect a malignant tumor. Methods: A prospective histological evaluation of vertebral body biopsy specimens from presumed osteoporotic vertebral compression fractures and a concurrent bone-marrow aspiration from the iliac crest were performed in order to identify latent hematopoietic dyscrasias. Over a four-year period, vertebral body biopsies from 523 vertebral levels as well as iliac crest bone-marrow aspirations were performed in 238 patients. Both specimens were evaluated histologically, and the prevalence of an underlying occult malignant neoplasm was determined. Results: All specimens from the vertebral bodies showed signs of bone-remodeling and/or fracture-healing. However, in three patients, both the bone biopsy specimen and the bone-marrow aspirate showed evidence of B-cell lymphoma. The bone-marrow aspirate did not provide any additional information compared with the vertebral body biopsy specimen, and multiple myeloma was not identified in any patient. Conclusions: Lymphoma is an uncommon cause of a vertebral compression fracture, but on the basis of our experience in this series, we recommend that vertebral body biopsy specimens be obtained in all patients managed with kyphoplasty and vertebroplasty to rule out an unsuspected malignant tumor. However, we do not recommend the routine use of an additional bone-marrow aspiration from the iliac crest during vertebral augmentation procedures because doing so did not appear to enhance our ability to detect a malignant tumor. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate objective functional and radiographic outcomes after internal fixation of acute, displaced, and unstable fractures of the distal aspect of the radius in adults by using a low-profile dorsal plating system. Our hypothesis was that the low-profile dorsal plating system would allow for a reduction of extensor tendon irritation and pain and provide stable osseous fixation. Methods: Sixty consecutive unstable fractures in 59 patients were treated by open reduction internal fixation using a low-profile dorsal plating system. There were 29 type A, 14 type B, and 8 type C fractures (AO classification system). Fifty patients with 51 fractures returned for outcomes assessment by physical examination, plain radiographs, and completion of a validated musculoskeletal function assessment questionnaire. The minimum follow-up period was 1 year; the mean follow-up period was 24 months. Clinical evaluation was performed and plain radiographs were assessed for maintenance of immediate postoperative reduction and implant position. Objective functional assessment was obtained through the Disabilities of the Arm, Shoulder, and Hand questionnaire. Results: Outcomes analysis showed no cases of extensor tendon irritation or rupture. Hardware removal was performed in 1 patient but no extensor tendon irritation or rupture was evidenced. The mean Disabilities of the Arm, Shoulder, and Hand score was 11.9; implant-related discomfort was minimal. All patients had an excellent (31 patients) or good (19 patients) result according to the scoring system of Gartland and Werley. The mean active range of motion was greater than 80% of that of the contralateral wrist in flexion/extension, pronation/supination, and ulnar/radial deviation. Extensor tendon function was unimpaired in all patients. Grip and pinch strength averaged 90% and 94% of the contralateral sides, respectively. Radiographic evaluation showed no change in fracture reduction or implant position. Conclusions: The treatment of distal radius fractures with a low-profile stainless steel dorsal plating system is a safe and effective method that provides stable internal fixation and allows for full extensor tendon glide and full metacarpophalangeal joint motion. Objective outcome testing showed uniformly good to excellent recovery of wrist and hand function in all patients. Type of study/level of evidence: Therapeutic, Level IV. [Copyright &y& Elsevier]

Further biomechanical and clinical studies are necessary to validate the efficacy of the Trochanteric Fixation Nail, but in our experience this is an improvement over the currently available devices. [ABSTRACT FROM AUTHOR]

Background: Treatment of osteoporosis following a hip fracture has been notoriously poor. Many efforts have been made to improve treatment rates. The purpose of this study was to determine whether a perioperative inpatient intervention program, involving patient education and providing a list of questions for the primary care physician, increased the percentage of patients in whom osteoporosis was addressed following a hip fracture. Methods: A prospective, randomized trial involving eighty patients who had been admitted to an academic medical center with a low-energy hip fracture was conducted. During their hospitalization, the study group patients were engaged in a fifteen-minute discussion regarding the association between osteoporosis and hip fractures, the efficacy of dual-energy x-ray absorptiometry scans in the diagnosis of osteoporosis and of bisphosphonates in its treatment, and the importance of medical follow-up for osteoporosis management. These patients were also provided with five questions regarding osteoporosis treatment to be given to their primary medical physician, and they were reminded about the questions during a follow-up telephone call six weeks later. The patients in the control group received a brochure describing methods for preventing falls. Both groups were contacted by telephone at six months after discharge to determine whether osteoporosis had been addressed. Positive indicators of intervention included assessment of bone mineral density with dual-energy x-ray absorptiometry and initiation of antiresorptive therapy. Results: The average age in each group was eighty-two years, and 78% of the patients were female. Four patients in each group did not survive through the six-month follow-up period and were excluded from the trial. Fifteen (42%) of the thirty-six patients who had been randomized to the study group, compared with only seven (19%) of the thirty-six patients in the control group, had their osteoporosis addressed by their primary physician. This difference between the groups was significant (p = 0.036). Conclusions: Patients who were provided with information and questions for their primary care physician about osteoporosis were more likely to receive appropriate therapeutic intervention than were patients who had not received the information and questions. Orthopaedic surgeons have a unique opportunity to improve the rate of osteoporosis treatment in the perioperative period following a hip fracture by educating patients and directing them toward channels for long-term osteoporosis management. Level of Evidence: Therapeutic study, Level I. See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Osteoporosis results in low-energy fractures of the spine. The load necessary to cause a vertebral fracture is determined by the characteristics related to the vertebral body structure, mineral content, and quality of bone. Radiographic techniques centered on dual X-ray absorptiometry (DXA) permit a determination of bone mass and fracture risk. Current medical therapies principally using bisphosphonate and pulsatile PTH profoundly decrease the risk of fracture (50+%). Fall prevention strategies can further decrease the possibility of fracture. A comprehensive approach to osteoporosis can favorably alter the disease. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is a common disease characterized by decreased bone mass and increased fracture risk in postmenopausal women and the elderly. Hip fractures are among the most common consequences of osteoporosis and unfortunately usually occur late in the course of the disease. When a patient is admitted to the hospital with a fragility hip fracture, a unique opportunity for diagnosis and treatment presents itself. Fortunately, several medications have proven to be effective in lowering the risk of future fractures. The purposes of the present study were to test the hypothesis that most fragility hip fractures go untreated and to determine whether educational efforts to raise physician awareness have led to an improvement in osteoporosis treatment rates. Methods: A retrospective cohort study was performed with use of the patient databases at two university medical centers and one university-affiliated community hospital. The charts of 300 randomly selected patients were sorted with use of ICD-9 (International Classification of Diseases, Ninth Revision) codes for femoral neck fractures. There were 100 patients from each center, with twenty-five patients from each year between 1997 and 2000. The admitting diagnosis, mechanism of injury, admission medications, procedures performed during hospitalization, and discharge medications were then extracted and analyzed. During this period, the National Osteoporosis Foundation established guiding principles for the treatment of fragility fractures. Results: Of the seventy-five patients from all centers for each year from 1997 to 2000, 11%, 13%, 24%, and 29%, respectively, were discharged with a prescription for some medication targeting osteopenia, either supplemental calcium or an antiosteoporotic medication (estrogen, calcitonin, a bisphosphonate, or raloxifene). A trended chi-square analysis of this increase revealed a p value of <0.001, indicating that this improvement in treatment was unlikely due to chance... [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the safety and efficacy of using lower profile 2.4/2.4 mm and 2.0/2.4 mm dual mini-fragment plate constructs for fixation of diaphyseal clavicle fractures.Methods: This was a retrospective case series of all displaced diaphyseal clavicle fractures treated with 2.4/2.4 and 2.0/2.4 dual mini-fragment plate constructs at a single level-one trauma center. Postoperative complications and fracture healing rates were recorded. A subset of patients with long-term follow up was used to determine the rate of reoperation for symptomatic implant removal.Results: All 36 identified fractures healed without loss of reduction or implant failure. There was one superficial infection and no deep infections or cases of wound dehiscence. Twenty patients from the entire cohort had longer-term follow up available to assess the reoperation rate for symptomatic implant removal. Two patients (10%) underwent symptomatic implant removal, and one patient with retained implants was planning on future removal due to soft-tissue irritation; this combined to a projected reoperation rate of 15% for symptomatic implant removal.Conclusion: Dual mini-fragment plating of diaphyseal clavicle fractures, using 2.4/2.4 mm and 2.0/2.4 mm plate combinations, creates a lower profile construct that reliably maintains fracture reduction to healing, and has a low rate of reoperation for symptomatic implant removal. [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to design and validate a novel stiffness-measuring device using locked plating of distal femur fractures as a model. Methods All patients underwent a laterally-based approach, with a bridging locked construct after indirect reduction. A custom and calibrated intraoperative stiffness device was applied and the stiffness of the construct was blindly recorded. Fourteen of twenty-seven patients enrolled with distal femur fractures (AO/OTA 33A and 33C) completed the study. Correlations between stiffness and callus formation, working length, working length/plate length ratio, number of distal locking screws, and fracture pattern were explored. Findings Callus and modified radiographic union scale in tibias scores as a linear function of stiffness did not correlate (R2 = 0.06 and 0.07, respectively). Construct working length and working length to plate length ratio did not correlate to stiffness (R2 = 0.18 and 0.16 respectively). A combined delayed and nonunion rate was 14%. Lower extremity measure scores were not statistically different when comparing delayed and nonunion with healed fractures. Interpretation The lack of correlation may have been due to the mechanical properties of the plate itself and its large contribution to the overall stiffness of the construct. To our knowledge, clinically relevant stiffness has not been described and this study may provide some estimates. This methodology and these preliminary findings may lay the groundwork for further investigations into this prevalent clinical problem. Other parameters not investigated may play a key role such as body mass index and bone mineral density. Level of evidence Diagnostic/Prognostic Level II. [ABSTRACT FROM AUTHOR]

Type 1 diabetes (T1DM) impairs bone formation and fracture healing in humans. Akita mice carry a mutation in one allele of the insulin-2 (Ins2) gene, which leads to pancreatic beta cell dysfunction and hyperglycemia by 5–6 weeks age. We hypothesized that T1DM in Akita mice is associated with decreased bone mass, weaker bones, and impaired fracture healing. Ins2 ± (Akita) and wildtype (WT) males were subjected to femur fracture at 18-weeks age and healing assessed 3–21 days post-fracture. Non-fractured left femurs were assessed for morphology (microCT) and strength (bending or torsion) at 19–21 weeks age. Fractured right femurs were assessed for callus mechanics (torsion), morphology and composition (microCT and histology) and gene expression (qPCR). Both Akita and WT mice gained weight from 3 to 18 weeks age, but Akita mice weighed less starting at 5 weeks (−5.2%, p < 0.05). At 18–20 weeks age Akita mice had reduced serum osteocalcin (−30%), cortical bone area (−16%), and thickness (−17%) compared to WT, as well as reduced cancellous BV/TV (−39%), trabecular thickness (−23%) and vBMD (−31%). Mechanical testing of non-fractured femurs showed decreased structural (stiffness, ultimate load) and material (ultimate stress) properties of Akita bones. At 14 and 21 days post fracture Akita mice had a significantly smaller callus than WT mice (~30%), with less cartilage and bone area. Assessment of torsional strength showed a weaker callus in Akita mice with lower stiffness (−42%), maximum torque (−44%) and work to fracture (−44%). In summary, cortical and cancellous bone mass were reduced in Akita mice, with lower bone mechanical properties. Fracture healing in Akita mice was impaired by T1DM, with a smaller, weaker fracture callus due to decreased cartilage and bone formation. In conclusion, the Akita mouse mimics some of the skeletal features of T1DM in humans, including osteopenia and impaired fracture healing, and may be useful to test interventions. • Bone structure and fracture healing in diabetic, male Akita mice at 18–21 weeks • Akita mice have low cortical and cancellous bone mass with low serum osteocalcin. • Fracture healing is impaired with smaller callus and reduced mechanical properties. • Akita mice are a useful model to study skeletal complications associated with T1DM. [ABSTRACT FROM AUTHOR]