A complete posterior tibial stress fracture that occurred during a middle-distance running race: a case report.

Posterior tibial stress fractures are more frequent than anterior tibial stress fractures, and they are considered to have a good prognosis for returning to sports; cases leading to a complete fracture are rare. A 17-year-old male involved in high school athletics middle-distance running had a 3-week history of pain with training. He was running up to 300 km/week on streets and cross-country in an even distribution. He had posterior tibial stress fractures, but despite the lower leg pain, he continued running. One year later, he was brought to the emergency department after having sustained an injury to the right lower leg while running in a middle-distance race; bilateral tibial stress fractures, with one side complete and the opposite side incomplete, had developed simultaneously. This relatively rare case of bilateral posterior stress fractures, with one side a complete fracture and the opposite side an incomplete fracture, that was treated surgically via exchange intramedullary nailing is reported. The patient could begin light jogging from 3 months after surgery and was without symptoms at 5 months after surgery. He could resume middle-distance racing after 1 year. Posterior tibial cortical fractures are more common and respond better to conservative treatment than anterior tibial stress fractures, and they are a common fracture type in runners. We believe that close, careful follow-up is necessary if patients continue excessive training.

Is actual surgical experience reflected in virtual reality simulation surgery for a femoral neck fracture?

INTRODUCTION: A virtual reality simulator developed for orthopaedic and trauma surgical training has been introduced. However, it is unclear whether the experiences of actual surgery are reflected in virtual reality simulation surgery (VRSS) using a simulator. The aim of this study is to investigate whether the results in VRSS differ between a trauma expert and a trauma novice. METHODS: In Group A (expert), there are ten orthopaedic trauma surgeons and in Group B (novice) ten residents within 2 years after medical school graduation. VRSS for a femoral neck fracture using Hansson hook-pins (Test 1) and Hansson twin hook plate (Test 2) was performed. The parameters evaluated were total procedure time (s), fluoroscopy time (s), number of times X-ray was used (defined by the number of times the foot pedal was used), number of retries in guide placement, and final implant position. RESULTS: In Test 1, the averages of four parameters (distance to posterior cortex (p = 0.009), distal pin distance above lesser trochanter (p = 0.015), distal pin hook angular error (p = 0.004), and distal pin tip distance to centre (lateral) (p = 0.015)) were significantly different between Groups A and B. In Test 2, no parameters in a mean were significantly different between groups, but seven parameters in a variance (guide wire distance to joint surface (p = 0.0191), twin hook length outside barrel (p = 0.011), twin hook tip distance to centre (lateral) (p = 0.042), twin hook distance to centre of lateral cortex (lateral) (p = 0.016), plate end alignment error (lateral) (p = 0.027), guide wire angle with lateral cortex (front) (p = 0.024), and 3.2-mm drill outside cortex (p = 0.000)) were significantly different between groups. In Test 1, Group B showed significantly longer fluoroscopy time than Group A (p = 0.044). In Test 2, Group B showed significantly fewer instances of X-ray use than Group A (p = 0.046). CONCLUSIONS: Our study showed that the experiences of actual surgery are reflected in the result of VRSS using the simulator.

"Within ring"-based sacroiliac rod fixation may overcome the weakness of spinopelvic fixation for unstable pelvic ring injuries: technical notes and clinical outcomes.

PURPOSE: Spinopelvic fixation and triangular osteosynthesis give firm internal fixation for unstable pelvic ring injuries (UPRI), but with sacrifice of mobility of the lumbar spine. Here, we describe the procedure and outcomes of a new approach, which we refer to as "within ring"-based sacroiliac rod fixation (SIRF). METHODS: The patient was placed in a prone position and longitudinal skin incisions were made at the medial margins of the bilateral posterior superior iliac spines (PSIS). After reduction of fracture, a pedicle screw was inserted into the first sacral vertebra on the injured side and iliac screws inserted through the bilateral PSIS were bridged using rods. RESULTS: SIRF was performed in 15 patients. The AO/OTA classification was 61-B2.3 in 1, C1.3 in 4, C2.3 in 7, C3.3 in 1, and H-type spinopelvic dissociation in two cases. The mean operative time was 179 (110-298) minutes, mean blood loss was 533 (100-2700) cc. One patient died during hospitalization and three patients stopped outpatient treatment. The other 11 patients achieved bone union without major loss of reduction in a mean post-operative follow-up period of 23.8 (4-50) months. The mean Majeed score at final follow-up was 86.7 (73-96) out of 96, excluding scoring sexual intercourse. CONCLUSIONS: "Within ring"-based SIRF not including the lumbar spine in the fixation range is a simple, safe, and low-invasive internal fixation method for UPRI.

A biomechanical study of sacroiliac rod fixation for unstable pelvic ring injuries: verification of the "within ring" concept.

PURPOSE: The aim of this study was to compare the fixation power of sacroiliac rod fixation (SIRF), which was developed based on our original "within ring" concept to exclude the lumbar vertebra from the fixation range, and spinopelvic fixation (SPF) in a biomechanical experiment. METHODS: SPF and SIRF were applied to the posterior element in four bones each with the pelvic ring fracture model (AO/OTA classification 61-C1.3). A 300-N axial force was loaded on the fifth lumbar vertebra of the simulated pelvis. Then the stiffness (N/m) and deformation (mm) of SPF and SIRF were determined, and the final displacement (mm) of the fracture region and angular deformity (degrees) were measured. Displacements were measured using the markers at two sites of the sacral fracture [upper margin of the sacral ala (Ala) and second sacral vertebra level (S2)] and one site of the pubic symphysis (PS), and angular deformity was measured at Ala and PS. RESULTS: In SPF and SIRF, the mean stiffnesses and deformations showed no statistically significant difference. Only the vertical displacement at Ala differed significantly between SPF and SIRF (p = 0. 045), and the fixing force of SPF was higher. There was no other significant difference in vertical and horizontal displacement. The mean angular deformities also showed no significant difference between the two methods. CONCLUSIONS: In biomechanics experiments, vertical resistance was stronger in SPF-treated than SIRF-treated bone, but stiffness and deformation, horizontal resistance, and angular deformity did not differ significantly.

Preservation of the articular capsule and short lateral rotator in direct anterior approach to total hip arthroplasty.

INTRODUCTION: In total hip arthroplasty via a direct anterior approach, the femur must be elevated at the time of femoral implant placement. For adequate elevation, division of the posterior soft tissues is necessary. However, if we damage and separate the posterior muscle tissue, we lose the benefits of the intermuscular approach. Furthermore, damage to the posterior soft tissue can result in posterior dislocation. We investigate that protecting the posterior soft tissue increases the joint stability in the early postoperative period and results in a lower dislocation rate. METHODS: We evaluated muscle strength recovery by measuring the maximum width of the internal obturator muscle on CT images (GE-Healthcare Discovery CT 750HD). We compared the maximum width of the muscle belly preoperatively versus 10 days and 6 months postoperatively. As clinical evaluations, we also investigated the range of motion of the hip joint, hip joint function based on the Japanese Orthopaedic Association hip score (JOA score), and the dislocation rate 6 months after surgery. RESULTS: The width of the internal obturator muscle increased significantly from 15.1 ± 3.1 mm before surgery to 16.4 ± 2.8 mm 6 months after surgery. The JOA score improved significantly from 50.8 ± 15.1 points to 95.6 ± 7.6 points. No dislocations occurred in this study. CONCLUSIONS: We cut only the posterosuperior articular capsule and protected the internal obturator muscle to preserve muscle strength. We repaired the entire posterosuperior and anterior articular capsule. These treatments increase joint stability in the early postoperative period, thus reducing the dislocation rate. LEVEL OF EVIDENCE: Therapeutic, Level IV.

Assessment of dorsal instability of the ulnar head in the distal radioulnar joint: comparison between normal wrist joints and cases of ruptured extensor tendons.

In the present study, the adaptability of the distal radioulnar joint (DRUJ) was evaluated using conventional computed tomography (CT) evaluation methods. In addition, we investigated/compared a new method to evaluate dorsal displacement of the ulnar head. Our subjects consisted of 32 healthy volunteers (64 wrists) and 11 patients (13 wrists) with extensor tendon injuries related to dorsal displacement of the ulnar head. To diagnose instability in the DRUJ based on CT scans, the radioulnar line method and the modified radioulnar line method were measured. Instability was evaluated by the new method that the ulnar head was located on the dorsal side from a line involving the peak of Lister's tubercle in parallel to this baseline was regarded as showing abnormal dorsal displacement of the ulnar head. The diagnostic accuracy of each method was calculated. The sensitivities, specificities, false-positive rates, positive predictive values and the negative predictive value of new methods were better than other two methods. The new method that we recommend is simple. Based on the results of this study, an evaluation of normal/abnormal dorsal displacement of the ulnar head in the DRUJ using the new method may be useful for determining the timing of surgery.

The incidence of and risk factors for developing atypical femoral fractures in Japan.

The long-term treatment with anti-resorptive drugs for osteoporotic patients is suggested to be associated with an increase in atypical femoral fractures (AFFs). However, their incidence, patient characteristics, and risk factors have not been fully elucidated especially in Asian countries. This retrospective observational cohort study found fourteen AFFs in ten patients (four bilateral fractures) among 2,238 hip and femoral shaft fractures treated in our associated hospitals between 2005 and 2010; this incidence (0.63%) was similar to Caucasians. Of the ten patients with AFFs, nine (90%) and six (60%) were using bisphosphonates (BPs) and glucocorticoids (GCs), respectively, compared to 14.3 and 8.6% for patients with typical femoral fractures who were using these agents. As comorbid conditions, five patients had collagen disease (CD) and two had diabetes. A fracture location-, age- and gender-matched (1:3) case-control study revealed that administration of BPs, GCs, and suffering from collagen disease (CD) were significant risk factors for developing AFFs [odds ratios 36.0 (95% confidence intervals 3.8-342.2), 13.0 (2.3-74.1) and 9.0 (1.6-50.3), respectively]. Interestingly, all of the patients with atypical subtrochanteric femoral fractures, defined as those within 5 cm of the lesser trochanter, were taking GCs due to CD, and the age of these patients (average of 54.8 years) was significantly younger than those with atypical diaphyseal femoral fractures (average of 77.2 years, p < 0.05). In conclusion, the incidence of AFFs in the Japanese population was similar to that of Caucasians, and taking BPs and GCs and suffering from CD were risk factors for developing AFFs.

Treatment strategy for distal radius fractures with ipsilateral arteriovenous shunts.

PURPOSE: To describe our management of 3 patients with chronic renal failure who sustained distal radius fractures in limbs containing dialysis shunts. METHODS: The 3 patients were 48-61 years old, and 2 of them were men. Because the injured limbs contained arteriovenous shunts, tourniquets were not used. Volar locking plate fixation was applied via the Henry approach. The patients' grip strength; visual analog scale scores; Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) scores; modified Mayo scores; and their range of wrist joint motion were assessed during the final follow-up examination. In addition, complications and the presence/absence of dysfunction of the forearm shunt were also investigated. RESULTS: The mean duration of the postoperative follow-up period was 9 months (range, 7-10 mo), and the subjects' mean wrist motion values were 75°, 79°, 78°, and 87° during flexion, extension, pronation, and supination, respectively. Grip strength on the affected side as a percentage of that seen on the healthy side ranged from 71% to 90%. The patients' visual analog scale; QuickDASH; and modified Mayo scores were all excellent, and bone union was achieved in all 3 cases. No shunt dysfunction or skin soft tissue complications were noted. CONCLUSIONS: Volar locking plate fixation via the Henry approach might be useful for treating distal radius fractures in cases in which an arteriovenous shunt is present in the same limb. Shunt dysfunction and hemorrhaging are of concern during open surgery, but these were not issues in our patients. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Irreducible dislocation of the thumb interphalangeal joint due to displaced flexor pollicis longus tendon: case report and new reduction technique.

Dislocation of the thumb interphalangeal (IP) joint is uncommon because of the inherent stability of the joint. Cases in which reduction was blocked by the volar plate, the flexor pollicis longus (FPL) tendon, the sesamoid bone, and an osteochondral fragment have been described in the literature. This article reports a case of closed thumb IP joint dislocation caused by the displacement of the FPL tendon. A new percutaneous reduction technique for this injury will also be presented. A 63-year-old woman presented to the emergency room with an obvious thumb deformity. Radiographs confirmed dorsal dislocation of the thumb IP joint without associated fracture. Closed reduction was not successful. Percutaneous reduction was performed under locoregional anesthesia, because the dislocation was due to an FPL tendon that had displaced dorsally and radially to the proximal phalanx. After reduction, Kirschner wire fixation was not needed, but IP joint immobilization with a splint was required for 3 weeks. Postoperatively, there were no complications in soft tissues and the operative scar was almost unrecognizable. This technique enables a mini-invasive reduction by operating percutaneously on the FPL. In addition, unlike with a volar zigzag approach, it is possible to suppress the occurrence of postoperative adhesion of the flexor tendon. This new minimally invasive reduction technique is useful for irreducible dislocation of the thumb IP joint due to a displaced FPL tendon.

Finite element analysis of mechanical stress in a cementless tapered-wedge short stem in the varus position.

BACKGROUND: In recent years, the use of tapered-wedge short stems has increased due to their ability to preserve bones and tendons. Surgical techniques occasionally result in a varus position of the stem, which is particularly pronounced in short stems. Although the varus position is not clinically problematic, there are reports of an increased incidence of stress shielding and cortical hypertrophy. Thus, we evaluated and examined the acceptable range of varus angles using finite element analysis. METHODS: Patients diagnosed with osteoarthritis of the hip joint who had undergone arthroplasty were selected and classified into three types [champagne-flute (type A), intermediate (type B), and stovepipe (type C)]. Finite element analysis was performed using Mechanical Finder. The model was created using a Taperloc microplasty stem with the varus angle increased by 1° from 0° to 5° from the bone axis and classified into seven zones based on Gruen's zone classification under loading conditions in a one-leg standing position. The volume of interest was set, the mean equivalent stress for each zone was calculated. RESULTS: A significant decrease in stress was observed in zone 2, and increased stress was observed in zones 3 and 4, suggesting the emergence of a distal periosteal reaction, similar to the results of previous studies. In zone 2, there was a significant decrease in stress in all groups at a varus angle ≥ 3°. In zone 3, stress increased from ≥ 3° in type B and ≥ 4° in type C. In zone 4, there was a significant increase in stress at varus angles of ≥ 2° in types A and B and at ≥ 3° in type C. CONCLUSION: In zone 2, the varus angle at which stress shielding above Engh classification grade 3 may appear is expected to be ≥ 3°. Distal cortical hypertrophy may appear in zones 3 and 4; the narrower the medullary cavity shape, the smaller the allowable angle of internal recession, and the wider the medullary cavity shape, the wider the allowable range. Long-term follow-up is required in patients with varus angles > 3°.

Triceps tendon avulsion: a case report and discussion about the olecranon ossification nucleus.

Rupture of the triceps tendon is a rare condition. We report a case of triceps tendon rupture with avulsion fracture of the olecranon with discussion about pathogenesis from the viewpoint of healing of the olecranon ossification nucleus. An 18-year-old man presented with avulsion fracture of the olecranon and triceps tendon rupture. Operative treatment was conducted with good results. Rupture of the triceps tendon is a rare injury comprising approximately 2% of all tendon injuries, and avulsion at insertion into the olecranon is the most common site of rupture. This injury is most likely to happen in young people as sports-related trauma. Among young people who have insufficient healing of the olecranon ossification nucleus, avulsion fracture of the olecranon may occur due to strong contraction force of the triceps tendon. Our clinical evidence may suggest that avulsion fracture of the olecranon is related in olecranon ossification center healing. Most triceps tendon ruptures are accompanied by avulsion fracture of the olecranon, and it is important to suspect this injury when radiographs show a small fleck of bone avulsed from the olecranon.

Limitation of total hip arthroplasty of the acetabular roof by press-fit without screw fixation: discussion of a biomechanical study.

In total hip arthroplasty of the acetabular roof fixed by press-fit without screw fixation, there is little possibility for loosening to occur, because it is difficult for wear debris to enter between the cup and the acetabular roof, as screw holes are not present. However, stability is provided only by contact. In the case of acetabular dysplasia, it is not well understood whether sufficient initial fixation power is provided. We performed a torsion test and a lever-out test. In the torsion test, in the case of a normal hip joint, as the cup grew bigger, the fixation power tended to increase in strength. In the acetabular dysplasia model, with cups of each size, as the protrusion angle increased, the fixation power of the cup tended to become weak. When the protrusion angle approaches 15 degrees, we must use a cup that is 4 mm larger than the original cup to achieve the same initial fixation power. Furthermore, when the protrusion angle is 15 degrees in cups that are over 48 mm in size, we obtain fixation power that is theoretically adequate, but when small cups, for example, 46 mm in size are set with protrusion, the initial fixation power decreases significantly, and we cannot obtain a fixation power that is theoretically adequate.

Early results of intramedullary nail fixation in distal tibia oblique osteotomy for the reduction of soft tissue complications.

PURPOSE: During distal tibial oblique osteotomy, external fixators can increase pin site infection risk, whereas plates can cause wound necrosis, necessitating a compromise between soft-tissue position and length. We provide the first report of the early results of intramedullary nail fixation in these osteotomies for avoiding soft tissue complications. METHODS: Ten ankles, classed as Takakura-Tanaka stages 3a to 4 and unclassified and treated via distal tibial oblique osteotomy for ankle osteoarthritis between 2017 and 2021, were included. Osteotomy was performed obliquely from the distal medial tibia to the tibiofibular joint. The distal tibial fragment was rotated distally in the coronal plane for realignment. An intramedullary nail fixation was applied for stabilization. The resulting gap was filled with iliac bone graft. Ankles were evaluated on the Japanese Society for Surgery of the Foot ankle-Hindfoot Scale and Self-Administered Foot Evaluation Questionnaire before surgery and at final follow-up. Radiographic assessments were performed. RESULTS: Bone union was achieved within 3 months in all patients. There were no cases of wound necrosis or correction loss postsurgery. Japanese Society scale scores significantly improved from 40.3 ± 15.9 to 87.5 ± 12.6 (P < 0.01). Mean self-evaluation scale scores (pain and pain-related, physical functioning and daily living, social functioning, general health and well-being) improved significantly. shoe-related scores did not change significantly but improved. There was no correction loss after surgery, with an average widening of 24.2 mm and opening angle of 22.6° at the osteotomy site. CONCLUSION: Our study showed that intramedullary nail for fixation of the osteotomy site in distal tibial oblique osteotomy effectively prevents soft tissues complications even in osteotomy sites with large openings.

A novel technique for stabilising sacroiliac joint dislocation using spinal instrumentation: technical notes and clinical outcomes.

PURPOSE: Currently, sacroiliac joint dislocations, including crescent fracture-dislocations, are treated using several techniques that have certain issues. We present the technical details and clinical outcomes of a new technique, anterior sacroiliac stabilisation (ASIS), performed using spinal instrumentation. METHODS: ASIS is performed with the patient in a supine position via the ilioinguinal approach. The displacements are reduced and fixed by inserting cancellous screws from the sacral ala and iliac brim; the screw heads are bridged using a rod and locked. We performed a retrospective review of patients with iliosacral disruption who underwent ASIS between May 2012 and December 2020 at two medical facilities. The patients were assessed for age, sex, injury type, associated injuries, complications, functional outcome by evaluating the Majeed pelvic score after excluding the sexual intercourse score and fracture union. RESULTS: We enrolled 11 patients (median age: 63 years). The median operative time was 195 min, median blood loss was 570 g, and eight patients (72.3%) required blood transfusion. The sacral and iliac screws had a diameter of 6.0-8.0 mm and 6.2-8.0 mm, and a length of 50-70 mm and 40-80 mm, respectively. Bone union was achieved with no marked loss of reduction in the median follow-up period of 12 months in all cases. The median Majeed score at the final follow-up was 85/96. CONCLUSION: ASIS is a rigid internal fixation method that provides angular stability. Despite invasiveness issues compared to iliosacral screw fixation, this method is easy to confirm and achieves precise reduction.

Total hip arthroplasty for a woman with hemophilia A -case report.

Hemophilia A is a congenital bleeding disorder caused by an X-linked hereditary pattern. Female hemophilia A carriers are usually asymptomatic, although some have far lower levels of clotting factor because more X chromosomes with the normal gene are switched off, a phenomenon referred to as "lyonization." During a medical checkup at our hospital, a 56-year-old Japanese woman with coxalgia was also diagnosed as an obligate hemophilia A carrier based on World Federation of Hemophilia criteria. She underwent total hip arthroplasty using blood product coagulation factor VIII to address her hemophilia. Immediate female relatives (mother, sisters, daughters) of a person with hemophilia should have their clotting factor levels checked, especially prior to any invasive intervention or childbirth, or if any symptoms occur.

Paradoxical Embolization of the Bilateral Subclavian Arteries After High Tibial Osteotomy.

A patent foramen ovale provides a portal through which a thrombus might pass from the right side of the circulation to the left. A 65-year-old man underwent high tibial osteotomy after the diagnosis of the right knee osteoarthritis. On postoperative day 12, he developed bilateral arm paresthesia. Enhanced CT revealed emboli in the bilateral pulmonary and subclavian arteries and deep vein thrombosis in the left lower limb. Transesophageal echocardiography after treatment revealed a patent foramen ovale during the Valsalva maneuver. It was thought that bilateral arm paresthesias were caused by the arterial emboli in the bilateral subclavian arteries.

Functional Outcomes in Volar-Displaced Distal Radius Fractures Patients with Marginal Rim Fragment Treated by Volar Distal Locking Plates.

Background Treatment of volar-displaced distal radius fractures (DRF) accompanied by marginal rim fragment has recently been actively discussed. It is difficult to obtain a sufficient buttress effect on this fragment. Therefore, we actively apply a distal volar locking plate (DVLP) to fractures with this fragment. Here, we report the treatment outcomes and caveats of surgery of fractures with this fragment. Materials and Methods The subjects were 32 patients (male: 11, female: 21, and mean age: 59.4 years) with volar dislocated DRF accompanied by the marginal rim fragment treated using DVLP. The fracture type of AO classification was B3 in 6 patients, C1 in 12, C2 in 6, and C3 in 8. Results The mean duration of follow-up was 13.8 (12-30) months. The plate could be covered with the pronator quadratus muscle in surgery in all patients. On the final follow-up, visual analog scale score was 1.4/10, quick disabilities of the arm, shoulder, and hand score was 9.2/100, and the Mayo wrist score was 93.7/100. No complication was observed in the soft tissue, such as the nerves and flexor tendons. Conclusion The factor determining retention of the reduction position of the marginal rim fragment is a sufficient buttress effect, and DVLP is a useful implant in terms of this point.