Effect of Interlocking Mode on the Outcomes of Exchange Nailing for the Treatment of Aseptic Femoral Shaft Nonunion

Background@#Exchange nailing is a standard treatment for femoral shaft nonunion after intramedullary nailing. However, substantial uncertainty and controversy remain regarding the mode of interlocking fixation. This study aimed to compare the success rate and time to union of exchange nailing based on interlocking modes. @*Methods@#We retrospectively analyzed all consecutive patients who underwent exchange nailing for aseptic femoral shaft nonunion between February 2000 and February 2021. Patients who underwent exchange nailing using the dynamically locked mode and statically locked mode constituted the dynamic group and static group, respectively. We compared the success rates of the index surgery and the time to union between the groups and measured the extent of interlocking screw migration on the dynamic oblong hole in the dynamic group. @*Results@#The dynamic group and static group comprised 17 patients and 18 patients, respectively. All patients in the dynamic group achieved bone union, whereas 5 patients in the static group did not and underwent additional intervention. The success rate of the index surgery was significantly higher in the dynamic group than in the static group (100% vs. 72.2%, p = 0.045). Four of the 5 failed unions in the static group achieved bone union after dynamization. The median time to union was significantly shorter in the dynamic group than in the static group (6.0 months [range, 4.0–6.0] vs. 12.0 months [range, 3.7–21.7], p= 0.035). In the dynamic group, 3 of 17 patients exhibited interlocking screw migration ranging from 1.1 to 4.1 mm. @*Conclusions@#Exchange nailing with dynamic mode yields a higher success rate and shorter time to union in aseptic femoral shaft nonunion than that with static mode, without the risk of excessive shortening.

Localization of Atypical Femoral Fracture on Straight and Bowed Femurs

BACKGROUND: To elucidate the effect of anterolateral bowing on the fracture height of atypical femoral fractures (AFFs), we separated the AFFs into 2 groups according to the presence of anterolateral femoral bowing (straight group and bowing group) and analyzed the fracture height. The aims of this study were to evaluate the clinical and radiological features of AFFs in the straight group and bowing group, and to determine which factors were associated with the fracture height of AFFs in the total cohort and each subgroup. METHODS: Ninety-nine patients with AFFs were included in this study (43 patients in the bowing group and 56 patients in the straight group). Clinical and radiological characteristics were compared between the groups. Multivariable linear regression analysis was performed to determine the effect of factors on fracture height. RESULTS: Patients in the straight group were younger, heavier, and taller, and had a higher bone mineral density, smaller anterior and lateral bowing angles, and more proximal fracture height than those in the bowing group. Multivariable analysis showed that the presence of anterolateral bowing itself and height were associated with fracture height in the total cohort. In the subgroup analysis, the lateral bowing angle in the straight group and the estimated apex height in the bowing group were associated with fracture height. The lateral bowing angle was not significantly associated with fracture height in the total cohort and the bowing group. CONCLUSIONS: The presence of anterolateral bowing and the level of the apex of the bowed femur were important factors for the fracture height of AFFs.

The Effects of Extramedullary Reduction in Unstable Intertrochanteric Fracture: A Biomechanical Study Using Cadaver Bone

PURPOSE: To prevent excessive sliding and subsequent fixation failures in unstable intertrochanteric fractures with posteromedial comminution, extramedullary reduction through overlapping of the anteromedial cortices of both proximal and distal fragments as a buttress has been introduced. The purpose of this study was to compare the biomechanical properties between two reduction methods-intramedullary reduction and extramedullary reduction-in treating unstable intertrochanteric fractures with posteromedial comminution (AO/OTA classification 31-A2.2). MATERIALS AND METHODS: Eight pairs of frozen human cadaveric femora were used. The femora of each pair were randomly assigned to one of two groups: the intramedullary reduction group or the extramedullary reduction group. A single axial load-destruction test was conducted after cephalomedullary nailing. Axial stiffness, maximum load to failure, and energy absorbed to failure were compared between the two groups. Moreover, the pattern of mechanical failure was identified. RESULTS: The mean axial stiffness in the extramedullary reduction group was 27.3% higher than that in the intramedullary reduction group (422.7 N/mm vs. 332.0 N/mm, p=0.017). Additionally, compared with the intramedullary reduction group, the mean maximum load to failure and mean energy absorbed to failure in the extramedullary group were 44.9% and 89.6% higher, respectively (2,848.7 N vs. 1,966.5 N, p=0.012 and 27,969.9 N·mm vs. 14,751.0 N·mm, p=0.012, respectively). In the intramedullary reduction group, the mechanical failure patterns were all sliding and varus deformities. In the extramedullary reduction group, sliding and varus deformities after external rotation were noted in 3 specimens, sliding and varus deformities after internal rotation were noted in 3 specimens, and medial slippage was noted in 2 specimens. CONCLUSION: In unstable intertrochanteric fractures with posteromedial comminution, the biomechanical properties of extramedullary reduction are superior to those of intramedullary reduction. Anteromedial cortex could be the proper buttress, despite a comminuted posteromedial cortex. It could help enhance the stability of the bone-nail construct.

Oncogenic Osteomalacia with Multiple Insufficiency Fractures: A Case Report

Oncogenic osteomalacia is a rare paraneoplastic syndrome, characterized by hypophosphatemia, renal phosphate wasting, osteomalacia, and multiple insufficiency fractures, as a result of the tumor. A wide excision of the causative tumor is considered as the treatment of choice, following which, a dramatic recovery is expected. Authors report a case in which the symptoms and bone mineral density were dramatically recovered after an excision of the causative tumor around the tibialis posterior muscle in oncogenic osteomalacia.

Paget's Disease: Skeletal Manifestations and Effect of Bisphosphonates

BACKGROUND: Paget's disease of bone leads to change in the shape and size of the bone and results in reduced bone strength, leading to the complications of deformity, arthritis, and fracture. Due to unknown reasons, Paget's disease is rare in Asian descendants. We report the cases of Paget's disease who visited our institute for 15 years and reviewed the literatures. METHODS: We retrospectively reviewed the medical records and radiograms of 8 patients (6 female and 2 male) who were diagnosed as Paget's disease of bone. Diagnosis was confirmed by typical radiological feature in the involved skeletons and/or pathologic findings. RESULTS: Pelvis, skull and spine were three most frequently involved bones. All involved bones in our cases showed changes in shape and trabecular pattern which resulted in bowing of lower extremity, secondary osteoarthritis, compression fracture of spine and enlargement of skull. Mean follow time was 4.71 years and all patient were treated bisphosphonate (BP). Use of BP controlled the level of serum alkaline phosphatase level effectively. CONCLUSIONS: We have reviewed eight patients who were previously diagnosed as Paget's disease of bone in our institute. We could identify typical radiologic and clinical findings such as bowing deformity of long bone, secondary osteoarthritis, compression fracture and osteomyelitis of mandible that deteriorated the quality of their living.

Preservation of Scaphoid in Scaphoid Nonunion Advanced Collapse Stage II and III / 대한정형외과학회잡지

PURPOSE: The purpose of this study is to investigate the outcome of open reduction and internal fixation with a headless screw and auto iliac bone graft for patients of scaphoid nonunion advanced collapse (SNAC) stage II and III. MATERIALS AND METHODS: A retrospective analysis was conducted for 10 patients diagnosed with stage II or III SNAC, and consequently treated with open reduction and internal fixation with a headless screw and auto iliac bone graft with or without radial styloidectomy between 2010 and 2013. Radiographic results were evaluated by bone union, the scapholunate angle and lateral intrascaphoid angle. Clinical results were evaluated by range of motion, pain, grip strength, Mayo wrist score, and assessment of Maudsley. RESULTS: All patients showed union after the operation. Final follow-up X-rays show smoothening of the articular surface with improvement of sclerotic lesions of the articular surface, cystic lesions and osteopenic lesions. Pain decreased after the operation compared with preoperative status, grip strength and Mayo wrist score showed significant improvement. Scapholunate angle and lateral intrascaphoid angle decreased after the operation, but it was not significant. According to assessment of Maudsley, among 10 cases, there were 4 excellent cases, 4 good cases and 2 fair cases. CONCLUSION: Restoration of stability of scaphoid is important to SNAC stage II and III, open reduction and internal fixation with a headless screw and auto iliac bone graft shows satisfactory clinical and radiologic outcomes. Thus it is considered a recommendable operation.

Amputation in Diabetic Foot Ulcer and Infection / 대한족부족관절학회지

Amputation of diabetic foot ulcer and infection is a critical modality for saving a patient's life from life threatening infections or ischemic limbs. However, it can cause serious handicaps or complications, such as lifetime shortening and re-amputation of the other limb. The minimal amputation is the main goal of amputation in diabetic patients. However, insufficient amputation can have a harmful effect on patients. The decision of amputation is very difficult and should be made using multidisciplinary approaches. All aspects of the patient's situation, including vascular status, degree of infection, and medical conditions should be considered. The foot surgeon should keep in mind the notion that proper amputation can lead to a new life for diabetic foot patients.