Potential of Titanium Pins Coated with Fibroblast Growth Factor-2-Calcium Phosphate Composite Layers to Reduce the Risk of Impaired Bone-Pin Interface Strength in the External Fixation of Distal Radius Fractures.

Background: The risk of impaired bone-pin interface strength in titanium (Ti) pins coated with fibroblast growth factor (FGF)-calcium phosphate (CP) composite layers is yet to be evaluated in a clinical study. This retrospective study used Weibull plot analysis to evaluate bone-pin interface strength in Ti pins coated with FGF-CP layers for external distal radius fracture fixation. Methods: The distal radial fractures were treated with external fixation. The FGF-CP group comprised five patients (all women, aged 70.4 ± 5.9 (range: 62-77) years), and the uncoated pin group comprised ten patients (eight women and two men, aged 64.4 ± 11.7 (range: 43-83) years). The pins were removed after six weeks. The insertion and extraction peak torques were measured. The extraction peak torque was evaluated using Weibull plot analysis. Results: We compared the extraction torque of the two groups at or below 506 Nmm for a fair comparison using Weibull plot analysis. The Weibull plots were linear for both the FGF-CP and uncoated pin groups. The slope of the regression line was significantly higher in the FGF-CP group (1.7343) than in the uncoated pin group (1.5670) (p = 0.011). The intercept of the regression line was significantly lower in the FGF-CP group (-9.847) than in the uncoated pin group (-8.708) (p = 0.002). Thus, the two regression lines significantly differed. Conclusions: Ti pins coated with FGF-CP layers exhibit the potential to reduce the risk of impaired bone-pin interface strength in the external fixation of distal radius fractures.

Retroperitoneal abscess associated with closed pelvic ring fracture diagnosed by fine free air on initial trauma pan computed tomography scan.

The patient was a 49-year-old male. He had a closed fracture of the pelvic ring that was treated successfully by avoiding anterior pelvic ring stabilization because of the presence of microscopic free air in the retroperitoneal space behind the pubic bone on initial whole-body trauma computed tomography scan. For his pelvic ring injury, transiliac rod and screw fixation was performed without the need for a pubic symphysis plate by developing the retroperitoneal space. His retroperitoneal abscess was treated by minimally invasive treatment of retroperitoneal abscess with computed tomography-guided percutaneous drainage. At 2 years postoperatively, there was no fever or elevated inflammatory response suspicious of retroperitoneal abscess recurrence. In this case, the presence of microscopic free air influenced the choice of treatment. Even in closed pelvic ring fractures, the presence of free air should be carefully considered when reading images.

Bisphosphonate-Related Atypical Femoral Fractures in Patients with Autoimmune Disease Treated with Glucocorticoids: Surgical Results for 20 Limbs.

BACKGROUND: Glucocorticoids induce osteoporosis, while bisphosphonates treat it, yet both can lead to atypical femoral fractures. Patients on both agents may face challenges in healing from such fractures due to their pathophysiology and pharmacological effects. METHODS: Intramedullary nail surgery was performed on 20 limbs in 19 patients with atypical femoral fractures and autoimmune diseases, who had received bisphosphonates for GC-induced osteoporosis. The average durations of glucocorticoid and bisphosphonate use were 17 and 9 years (standard deviation: 7.59 and 4.35), respectively, and the mean follow-up period was 66 months. Fifteen and five limbs were fractured at the subtrochanter and diaphysis, respectively. The surgical techniques (type of nail) and additional procedures performed in these cases were examined. The post-operative alignment and reduction status on radiographs were examined to determine their relationship with post-operative outcomes. RESULTS: Cephalomedullary long nails were inserted in nine limbs and antegrade intramedullary nails in 11 limbs. As an additional surgical procedure, open reduction, bone grafting and drilling were carried out on six, two, and five limbs, respectively. Regarding malalignment on radiographs, AP images showed varus in four limbs, and lateral images showed extension in two limbs. Regarding the cortical discontinuity, the distal fragment of the 11th limb shifted posteriorly in the lateral view. Gaps at the fracture sites were observed in 11 limbs. As a result, bone union was confirmed in 13 limbs. Five of the seven nonunion limbs required additional surgery. When comparing union and nonunion, open reduction and drilling were involved in nonunion limbs. CONCLUSION: The surgical outcomes of atypical femoral fractures in patients with autoimmune disease and on long-term glucocorticoids and bisphosphonates were poor. Although it is not possible to affirm for sure based on these results alone, management with prophylactic surgery before complete fracture is considered to be required to improve outcomes.

A case report of circular external fixator with low-profile mini-fragment plate fixation: A combination of two methods for a tibial pilon fracture.

Tibial pilon fractures are difficult to treat. These fractures are associated with a high frequency of soft tissue complications. Therefore, two-stage surgery and less invasive surgical strategies using external fixation have been reported. The patient was a 79-year-old man. The right tibial pilon fracture was diagnosed as AO/OTA 43C3.1, Rüedi and Allgöwer type 2. He was treated with a low-profile mini-fragment plate and circular (Ilizarov type) external fixation. Herein, we report on a combination of these two methods: circular external fixator with low-profile mini-fragment plate fixation. At 18 months postoperatively, the American Orthopaedic Foot & Ankle Society Ankle-Hindfoot score was a perfect score of 100. Radiographs taken in the loading position showed no narrowing of the joint fissure. There were no soft tissue infections, no plate breakage, no bone fusion, no symptoms of plate irritation, and no need for nail extraction.

Atypical tibial fracture in breast cancer patient with bone metastasis receiving denosumab therapy: a case report and review of the literature.

BACKGROUND: Denosumab therapy is often used to reduce skeletal-related events in metastatic bone disease. On the other hand, there have been some instances of atypical femoral fracture in patients with metastatic bone disease treated with denosumab. In this case report, we describe a patient with metastatic bone disease due to breast cancer who had been using denosumab for 4 years to prevent skeletal-related events and suffered an atypical tibial fracture. CASE PRESENTATION: We report here the case of an 82-year-old Japanese woman who had received yearly intravenous denosumab for 4 years and presented with a fracture fulfilling the criteria for an atypical fracture, except for being located at the tibial diaphysis. She was found to have stage 4 breast cancer with multiple bone metastases 4 years prior. She had difficulty walking due to her tibial pain and underwent surgical treatment. Four months after surgery, the tibial fracture site exhibited bone fusion. CONCLUSION: In patients with long-term use of denosumab to prevent skeletal-related events in metastatic bone disease, it is important to be aware of shin and thigh pain and to examine for signs of atypical tibial fractures to pay attention to atypical femoral fractures.

Safety and Osteointegration of Titanium Screws Coated with a Fibroblast Growth Factor-2-Calcium Phosphate Composite Layer in Non-Human Primates: A Pilot Study.

Spinal instrumentation surgery for older patients with osteoporosis is increasing. Implant loosening may occur due to inappropriate fixation in osteoporotic bone. Developing implants that achieve stable surgical results, even in osteoporotic bone, can reduce re-operation, lower medical costs, and maintain the physical status of older patients. Fibroblast growth factor-2 (FGF-2) promotes bone formation; thus, coating pedicle screws with an FGF-2-calcium phosphate (FGF-CP) composite layer is hypothesized to enhance osteointegration in spinal implants. We designed a long-term implantation pilot study that estimated the safety and bone-forming efficacy of pedicle screws coated with an FGF-CP composite layer in cynomolgus monkeys. Titanium alloy screws, either uncoated (controls) or aseptically coated with an FGF-CP composite layer, were implanted in the vertebral bodies of six female adult cynomolgus monkeys (three monkeys per group) for 85 days. Physiological, histological, and radiographic investigations were performed. There were no serious adverse events, and no radiolucent areas were observed around the screws in either group. The bone apposition rate in the intraosseous region was significantly higher in the FGF-CP group than in the controls. Moreover, as analyzed by Weibull plots, the bone formation rate of the FGF-CP group exhibited a significantly higher regression line slope than the control group. These results demonstrated that there was significantly less risk of impaired osteointegration in the FGF-CP group. Our pilot study suggests that FGF-CP-coated implants could promote osteointegration, be safe, and reduce the probability of screw loosening.

Clinical Trial for the Safety and Feasibility of Pedicle Screws Coated with a Fibroblast Growth Factor-2-Apatite Composite Layer for Posterior Cervical Fusion Surgery.

To solve the instrument loosening problem, we developed a fibroblast growth factor-2-calcium phosphate composite layer as a novel coating material to improve screw fixation strength. The primary aim of the present study was to demonstrate the safety and feasibility of screws coated with the FGF-2-calcium phosphate composite layer for posterior instrumented surgery of the cervical spine. The trial design was a single-arm, open-label, safety and feasibility study. Patients receiving fusion of the cervical spine from C2 (or C3) to C7 (or T1) were recruited. The primary endpoint to confirm safety was any screw-related adverse events. Seven patients who underwent posterior fusion surgery of the cervical spine were enrolled in the present study. The coated pedicle screws were inserted bilaterally into the lowest instrumented vertebrae. There was only one severe adverse event unrelated with the coated screw. Three out of the fourteen coated screws showed loosening. The present results prove the safety and feasibility of pedicle screws coated with the FGF-2-calcium phosphate composite layer for fusion surgery in the cervical spine. This is the first step to apply this novel surface coating in the field of spine surgery.

Safety of terminally gamma-ray-sterilized screws coated with fibroblast growth factor 2-calcium phosphate composite layers in non-human primates.

Screws coated with fibroblast growth factor 2 (FGF-2)-calcium phosphate (CP) composite layers exhibit enhanced soft tissue and bone formation and angiogenesis because of the biological activity of FGF-2. Furthermore, the mitogenic activity of the FGF-2 within the composite layers remains unchanged after gamma-ray sterilization, which may improve the storage stability prior to clinical use. However, the in vivo safeties of these screws as spinal implants remain unknown. Here, a randomized controlled trial, involving non-human primates, investigated the safety of using FGF-2-CP composite layer-coated screws after either gamma-ray sterilization or aseptic processing. Titanium alloy screws coated with FGF-2-CP composite layers and subjected to either gamma-ray sterilization at 25 kGy (GS group) or aseptic storage (AS group) were implanted into the vertebral bodies of two cynomolgus monkeys exceeding 12 weeks (day 99). Physiological, histological, and radiographic investigations were performed to evaluate the safeties of the screws. There were no serious adverse events, such as surgical site infection, significant loss of body weight, or abnormal blood test results. No radiolucent areas were observed around the screws from the GS or AS group throughout the study. In the intraosseous region, no significant differences were observed in bone and fibrous tissue apposition rates and rate of bone formation between the two groups (p = 0.49, 0.77, and 0.11, respectively). Neither tumor lesions nor accumulation of lymphocytes and neutrophils were observed in either group. Our data suggest that FGF-2-CP composite layer-coated screws subjected to terminal gamma-ray sterilization are as safe as those fabricated in aseptic processing.

Clinical Outcome of Sacroiliac Rod Fixation for Fragility Fracture of the Pelvis Rommens and Hoffman Classification Type IVb: Case Series.

Introduction: Fragility fracture of the pelvis (FFP), generally involving Rommens and Hoffman classification type IVb (H-shaped) requires spinopelvic fixation (SPF). We report the clinical outcome of sacroiliac rod fixation (SIRF) for FFP type IVb in a case series. Materials and Methods: In this retrospective observational study, six patients (mean age, 80.3 years; range, 74-85 years) with FFP type IVb who underwent SIRF since October 2019 and could be followed up for ≥1 year postoperatively were included. All patients were injured in low-energy falls, a patient had a femoral neck fracture, and other had a humeral neck fracture and distal radius fracture. Results: The mean (range) operative time was 135 (98-200) min, and mean blood loss was 103 (80-130) g. All patients achieved bone union in an average of 4.3 months. No implant failure or surgical site infection requiring reoperation occurred. No patient complained of iliac screw irritation or requested removal. One patient developed a T12 vertebral fracture at 3 weeks postoperatively. The mean final follow-up period was 17.8 months (13-22 months) and mean final modified Majeed Score (maximum 76 points as the items "work" and "sexual intercourse" were omitted for this study) was 71.7 (56-76). Conclusions: SIRF is a less invasive surgical technique than SPF that uses only an S1 pedicle screw and iliac screw. SIRF using the "within ring" concept showed good clinical outcome in FFP type IVb.

Internal fixation for fragility fracture of pelvis in a patient with ankylosing spondylitis.

Ankylosing spondylitis is a common inflammatory rheumatic disease with a prevalence of 0.1 %-1.4 %. The most common vertebral fractures associated with ankylosing spondylitis are cervical spine injuries due to low-energy trauma, whereas pelvic fractures are rare. Conversely, fragility fracture of the pelvis is a fracture of the pelvic ring caused by low-energy trauma with a background of bone fragility. In recent years, minimally invasive surgery for early mobilization of displaced fragility fracture of the pelvis has been reported. We report herein a case of a 91-year-old male with ankylosing spondylitis who underwent internal fixation for fragility fracture of his pelvis. He was brought to the emergency room with a complaint of pain in the right hip after a fall from a standing position at home. Computed tomography showed a fracture of the right pubis and a fracture, which crossed the sacrum from the ilium with a maximum dislocation. There was also extensive ossification of the anterior longitudinal ligament in the thoracolumbar spine and bony ankylosis of both sacroiliac joints. The diagnosis after the injury was fragility fracture of the pelvis, which complicated by ankylosing spondylitis. The fracture type did not match the Rommens and Hofmann classification criteria. Iliac intramedullary stabilization was performed in accordance with the treatment of Rommens and Hofmann classification type IIIa. The patient's pain reduced a day after the surgery, and he was able to use a wheelchair. He was able to walk with a cane two months after the surgery, and bone union was achieved four months postsurgery. Iliac intramedullary stabilization was useful in patients with atypical fractures a) that did not fit the Rommens and Hofmann classification criteria owing to the presence of ankylosing spondylitis, and b) in cases wherein strong fixation was considered necessary.

Set-screw loosening of spinopelvic crab-shaped fixation for a patient with vertically unstable pelvic ring fracture.

Spinopelvic fixation (SPF) is an effective treatment method for vertically unstable pelvic ring fractures with spinopelvic dissociations (Patel et al., 2022). A heavy container fell on a 35-year-old man who was trapped and sustained injuries. His pelvic ring fracture dislocation was identified as AO Classification 61-C2.3 with rotational and vertical unstable pelvic ring; thus, crab-shaped fixation (SPF modification) was performed (Okuda et al., 2019). The pelvic fracture was fused, and the clinical outcome was good with modified Majeed score of 96. However, set-screw loosening was observed during the postoperative course. Reports of implant failures in SPF for unstable pelvic ring fractures commonly occur. However, only a few reports have demonstrated implant failure of crab-shaped fixation. Written informed consent was obtained from the patient for publication of this case report and accompanying images.

The morphology of the sacral corridor for transiliac transsacral screw in Japanese osteoporotic vertebral fracture patients: Analysis using CT data.

[Introduction] Fragility fractures of the pelvic ring are increasing in the elderly population. A percutaneous sacroiliac screw is one of the methods used to fix of the posterior pelvic element with less dislocation. It is advantageous for elderly because minimally invasive insertion is possible; although there are few reports studying the Japanese population. Here, we investigated the Japanese sacral morphology and examined the feasibility of the percutaneous transiliac transsacral screw method. [Materials and Method] Seventy patients with osteoporotic vertebral fractures were included. For the measurement, CT images were analyzed using Zedhip (LEXI) based on the method of Goetzen. The column between S1 and S2 was classified into three groups, the ascending type, horizontal type, descending type, and the presence or absence of a notch was investigated. [Result] There were many ascending types in the center of S1, a few descending types, and many patients with a notch in the S2. There were many ascending types in middle of the S1 and many patients with a notch in middle of the S2 and lower quarter. [Conclusion] There is a tendency that indicates TITS screw penetration may be difficult in the S1, and it is necessary to consider the possibility of insertion via preoperative CT planning. Adaptation of the percutaneous TITS screw fixation technique for the Japanese elderly population with osteoporotic vertebral fractures should be carefully considered.

'Within Ring' Concept Treatment for Displaced H-Shaped Type IVb Fragility Fractures of the Pelvis.

INTRODUCTION: Sacroiliac rod fixation (SIRF) preserves the mobility of L5/S1 (lumber in the pelvis), as a surgical procedure for high-energy pelvic ring fractures. The concept of SIRF method without pedicle screws into L4 and L5 is called 'within ring' concept. Case Presentation. We report here the clinical results of 'within ring' concept treatment with sacroiliac rod fixation for a case of displaced H-shaped Rommens and Hofmann classification type IVb fragility fractures of the pelvis (FFP), which A 79-year-old woman had been difficult to walk due to pain that had been prolonged for more than one month since her injury. The patient was successfully treated with SIRF, no pain waking with a walking stick and returned to most social activities including living independently within 6 months of the operation. CONCLUSION: SIRF is useful because it can preserve the mobility in the lumbar pelvis; not including the lumbar spine in the fixation range like spino pelvic fixation is a simple, safe, and low-invasive internal fixation method for displaced H-shaped type IVb fragility fractures of the pelvis.

Technical note on the removal of a "cold-welded" lag screw from a Trigen Meta-Tan nail.

Intramedullary or cephalomedullary nail removal often is performed during nonunion reoperations. We have experienced a rare case in which it was difficult to remove the lag screw of the antegrade intramedullary nail, requiring a large amount of force to be applied over a long period. Removal of the lag screw is essential for removal of the nail and subsequent revision surgery. In our case, the lag screw could be removed only by cutting the screw with a carbide drill. For cases in which the nail and lag screw are firmly fixed, surgeons should prepare for the possibility of their separation using a carbide drill. Written informed consent was obtained from the patient for publication of this case report and accompanying images.

Novel method for selecting slices of the same cross-sectional view from digital tomosynthesis for monitoring posterior spinal instrumentation.

BACKGROUND: A method to evaluate pedicle screw loosening on digital tomosynthesis images is yet to be established owing to lack of methods for selecting slices of the same cross-sectional view. We aimed to develop an objective method for selecting slices of the same cross-sectional view on digital tomosynthesis images. METHODS: First, an objective method of pixel selection was developed by measuring the size of glass disk and titanium alloy screw on digital tomosynthesis images followed by comparison with the actual sizes. Second, a method for selecting slices of the same cross-sectional view was explored on a bone model with posterior spinal instrumentation using the screw centerline and rod curvature as indicators of the same cross section. The angle between the screw centerline and rod was calculated to verify the accuracy in obtaining the same cross-sectional view. Third, the method for selecting slices of the same cross-sectional view was applied to six patients after posterior lumbar spinal instrumentation. RESULTS: The pixel selection method enabled objective determination of a pixel on the peripheral lines of objects with an error as low as 200 µm in distance measurements on titanium alloy and glass. The mean differences of rod-screw angles between two slices were less than 1° and were not statistically significant in the bone model and patient images. CONCLUSION: A method for selecting slices of the same cross-sectional view on digital tomosynthesis images was successfully developed. This method can enable objective and quantitative evaluations of pedicle screw loosening.

Closed total talar dislocation without fracture in a rare college athlete case.

Total talar dislocation without a fracture is an extremely rare injury. It is often the result of high-energy trauma, such as that incurred after a fall, or owing to motor or vehicular accidents. Talar dislocations have poor outcomes owing to the frequent complications of infection, avascular necrosis and osteoarthritis attributed to open dislocations. We report herein a closed total talar dislocation without a fracture in a college athlete who was injured during sports activities. Specifically, a 20-year-old man was injured during a soccer game this led to a closed total talar dislocation. We performed closed reduction with image guidance subject to a popliteal sciatic nerve block, and placed a plaster cast below the knee. Radiographic studies after reduction revealed no associated fractures. After an eight week no-weight bearing period, we confirmed that there were no avascular necrosis signs on magnetic resonance images. Based on these findings, partial weight bearing was allowed. At 18 months post trauma, the athlete continues to play soccer despite the fact that he experiences a slight pain and limited range of motion. The blood supply to the talus is limited, and trauma, such as dislocation, can easily injure the blood supply, thus resulting in complications, such as avascular necrosis. The talus vascularity of the presented case was maintained by superior branches. We think that it is important to a) perform closed reduction early on, b) avoid any type of surgical operation that damages the limited talus blood supply, and c) allow weight bearing after the lack of avascular necrosis signs is confirmed. Although there is no standardized treatment, the talar dislocation treatment should be chosen to preserve the blood supply to the talus as much as possible.

Bilateral Osteochondritis Dissecans of the Talar Posterior Calcaneal Articular Surface in a Professional Soccer Player: A Case Report.

INTRODUCTION: Preferred sites of osteochondritis dissecans (OCD) are the distal femur and humerus, and the dome of the talus. We report a rare case of a professional soccer player with bilateral OCD of the talar posterior calcaneal articular surface. CASE REPORT: The left talus showed a loose but not displaced fragment, and pain was relieved with 3 months of conservative treatment. The right had two loose fragments that were displaced from their beds in the talar posterior calcaneal articular surface. The loose bodies were surgically excised. The player remains symptom free 4 years after the operation and participates in professional games. Thus, although OCD of the talar posterior calcaneal articular surface remains a relatively uncommon injury, we suggest that treatment methods tailored to the OCD stage as per Berndt and Harty classification may be successful. The exact causes and establishment of a treatment protocol in these cases will depend on the investigation of future cases. CONCLUSION: Since this case of OCD of the talar posterior calcaneal articular surface was bilateral, we hypothesized that it may have been caused by microtrauma in the sense of repetitive, excessive compression of the subchondral bone, or by a vascular etiology.

Impacts of chemically different surfaces of implants on a biological activity of fibroblast growth factor-2-apatite composite layers formed on the implants.

BACKGROUND: Implants coated with fibroblast growth factor-2 (FGF-2)-apatite composite layers were previously reported to enhance soft-tissue formation, bone formation, and angiogenesis around the implants owing to the biological activity of FGF-2. However, it is unclear whether the chemistries of the material and surface of implants have some impact on the retention of the biological activity of FGF-2 in FGF-2-apatite composite layers on them. Since magnitude of the impact should be evaluated for extensive application of the composite layer to coat various implants, following items were examined; (1) surface chemistries of six implants, (2) mitogenic activities of FGF-2 in FGF-2-apatite composite layers on the implants, and (3) improved synthesis method of the composite layer for retention of the mitogenic activity of FGF-2. HYPOTHESIS: The biological activity of FGF-2 in the composite layer is affected by the chemistries of the material and surface of implants. MATERIALS AND METHODS: Six commercial products of pins and screws having different surface chemistries were coated with FGF-2-apatite composite layers. The composite layers were quantitatively analyzed for calcium (Ca), phosphorus (P) and FGF-2, and also evaluated the mitogenic activities of FGF-2. Improvement of the synthesis method was then attempted using two pin products. RESULTS: Each commercial product had a chemically and morphologically characteristic surface. FGF-2-apatite composite layers were formed on all the commercial products. Although the Ca, P, and FGF-2 contents (4.7±0.9µg/mm, 2.2±0.4µg/mm, and 21.1±3.7ng/mm, respectively) and the Ca/P molar ratios (1.69±0.01) of the composite layers were almost the same, rate of retention of the mitogenic activity of FGF-2 in the composite layers significantly decreased on some pin products (3/12-4/12). The decrease in rate of retention of the mitogenic activity of FGF-2 was prevented by a two-step synthesis method to form a composite layer on a precoating with calcium phosphate (9/12-12/12). DISCUSSION: The chemistries of the implant surfaces had a significant impact on the retention of the mitogenic activity of FGF-2 in the composite layers formed on the implant. The two-step synthesis method was useful to retain mitogenic activity of FGF-2 regardless of the surface chemistries of the implants. The two-step synthesis method has potential to expand the applicability of FGF-2-apatite composite layers to a wider range of implants. LEVEL OF EVIDENCE: III, Case control in vitro study.

Closed reduction and minimally invasive surgical treatment of type IIIa fragility fractures of the pelvis associated with ipsilateral periprosthetic femur fracture: A case report.

Patients with fragility fractures of the pelvic ring (FFP) are elderly and, from the perspective of surgical invasion, percutaneous and stable fixation may be a superior surgical method than open reduction and internal fixation (ORIF). While in the case of FFP type IIIa, ORIF, as a rule, typically requires open reduction of the displaced ilium via an anterior intrapelvic approach and/or lateral window of the ilioinguinal approach. We have reported here the case of an 89-year-old woman who suffered from FFP type IIIa with ipsilateral periprosthetic femur fracture that was surgically treated. The iliac fracture was approached in a minimally invasive manner using the traction operation while preparing for femoral shaft fracture surgery, which did not require open reduction, and showed favorable outcomes.