Background: Long-term use of bisphosphonate is a risk factor for atypical femoral fractures (AFFs). Femoral bowing is known to be associated with AFFs. However, whether femoral bowing quickens the occurrence of AFF is unknown. The purpose of this study was to determine whether AFF occurs earlier in patients with severe femoral bowing than in those without severe bowing. Methods: One hundred and sixty-four patients (186 AFFs) from January 2006 to December 2022 were included in this study.According to severity of femoral bowing, patients were divided into 2 groups: severe bowing group (26 femurs) and minimal to moderate bowing group (160 femurs). Age, sex, and completeness and location of AFF were compared between the 2 groups. We compared the time of AFF occurrence after bisphosphonate therapy using cumulative percentage between the 2 groups. Results: Age and sex were similar between the 2 groups, while body mass index (BMI) was lower (22.5 ± 3.0 kg/m 2 vs. 24.5 ± 3.5 kg/m 2 , p = 0.003) in the severe bowing group. The duration of bisphosphonate use was shorter in the severe bowing group than in the minimal to moderate bowing group (3.3 ± 3.8 years vs. 5.0 ± 4.0 years, p = 0.048). In the severe bowing group, 85% of AFFs were diaphyseal in contrast to the 46% in the minimal to moderate bowing group (p < 0.001). Cumulative percentage plot of AFFs in the severe bowing group was left-shifted compared to the minimal to moderate bowing group. Conclusions At the time of AFF diagnosis, the severe bowing group exhibited shorter duration of bisphosphonate use, lower BMI, and a higher incidence of diaphyseal location. Shortening the duration of bisphosphonate therapy may be advisable in patients with severe femoral bowing.

Background: Long-term use of bisphosphonate is a risk factor for atypical femoral fractures (AFFs). Femoral bowing is known to be associated with AFFs. However, whether femoral bowing quickens the occurrence of AFF is unknown. The purpose of this study was to determine whether AFF occurs earlier in patients with severe femoral bowing than in those without severe bowing. Methods: One hundred and sixty-four patients (186 AFFs) from January 2006 to December 2022 were included in this study.According to severity of femoral bowing, patients were divided into 2 groups: severe bowing group (26 femurs) and minimal to moderate bowing group (160 femurs). Age, sex, and completeness and location of AFF were compared between the 2 groups. We compared the time of AFF occurrence after bisphosphonate therapy using cumulative percentage between the 2 groups. Results: Age and sex were similar between the 2 groups, while body mass index (BMI) was lower (22.5 ± 3.0 kg/m 2 vs. 24.5 ± 3.5 kg/m 2 , p = 0.003) in the severe bowing group. The duration of bisphosphonate use was shorter in the severe bowing group than in the minimal to moderate bowing group (3.3 ± 3.8 years vs. 5.0 ± 4.0 years, p = 0.048). In the severe bowing group, 85% of AFFs were diaphyseal in contrast to the 46% in the minimal to moderate bowing group (p < 0.001). Cumulative percentage plot of AFFs in the severe bowing group was left-shifted compared to the minimal to moderate bowing group. Conclusions At the time of AFF diagnosis, the severe bowing group exhibited shorter duration of bisphosphonate use, lower BMI, and a higher incidence of diaphyseal location. Shortening the duration of bisphosphonate therapy may be advisable in patients with severe femoral bowing.

Background: Long-term use of bisphosphonate is a risk factor for atypical femoral fractures (AFFs). Femoral bowing is known to be associated with AFFs. However, whether femoral bowing quickens the occurrence of AFF is unknown. The purpose of this study was to determine whether AFF occurs earlier in patients with severe femoral bowing than in those without severe bowing. Methods: One hundred and sixty-four patients (186 AFFs) from January 2006 to December 2022 were included in this study.According to severity of femoral bowing, patients were divided into 2 groups: severe bowing group (26 femurs) and minimal to moderate bowing group (160 femurs). Age, sex, and completeness and location of AFF were compared between the 2 groups. We compared the time of AFF occurrence after bisphosphonate therapy using cumulative percentage between the 2 groups. Results: Age and sex were similar between the 2 groups, while body mass index (BMI) was lower (22.5 ± 3.0 kg/m 2 vs. 24.5 ± 3.5 kg/m 2 , p = 0.003) in the severe bowing group. The duration of bisphosphonate use was shorter in the severe bowing group than in the minimal to moderate bowing group (3.3 ± 3.8 years vs. 5.0 ± 4.0 years, p = 0.048). In the severe bowing group, 85% of AFFs were diaphyseal in contrast to the 46% in the minimal to moderate bowing group (p < 0.001). Cumulative percentage plot of AFFs in the severe bowing group was left-shifted compared to the minimal to moderate bowing group. Conclusions At the time of AFF diagnosis, the severe bowing group exhibited shorter duration of bisphosphonate use, lower BMI, and a higher incidence of diaphyseal location. Shortening the duration of bisphosphonate therapy may be advisable in patients with severe femoral bowing.

Background: Long-term use of bisphosphonate is a risk factor for atypical femoral fractures (AFFs). Femoral bowing is known to be associated with AFFs. However, whether femoral bowing quickens the occurrence of AFF is unknown. The purpose of this study was to determine whether AFF occurs earlier in patients with severe femoral bowing than in those without severe bowing. Methods: One hundred and sixty-four patients (186 AFFs) from January 2006 to December 2022 were included in this study.According to severity of femoral bowing, patients were divided into 2 groups: severe bowing group (26 femurs) and minimal to moderate bowing group (160 femurs). Age, sex, and completeness and location of AFF were compared between the 2 groups. We compared the time of AFF occurrence after bisphosphonate therapy using cumulative percentage between the 2 groups. Results: Age and sex were similar between the 2 groups, while body mass index (BMI) was lower (22.5 ± 3.0 kg/m 2 vs. 24.5 ± 3.5 kg/m 2 , p = 0.003) in the severe bowing group. The duration of bisphosphonate use was shorter in the severe bowing group than in the minimal to moderate bowing group (3.3 ± 3.8 years vs. 5.0 ± 4.0 years, p = 0.048). In the severe bowing group, 85% of AFFs were diaphyseal in contrast to the 46% in the minimal to moderate bowing group (p < 0.001). Cumulative percentage plot of AFFs in the severe bowing group was left-shifted compared to the minimal to moderate bowing group. Conclusions At the time of AFF diagnosis, the severe bowing group exhibited shorter duration of bisphosphonate use, lower BMI, and a higher incidence of diaphyseal location. Shortening the duration of bisphosphonate therapy may be advisable in patients with severe femoral bowing.

Background: The purposes of this study were to determine the accuracy of our cup positioning method and to evaluate the dislocation rate after total hip arthroplasty (THA). Methods: After positioning the patient in the lateral decubitus position on the operation table, an anteroposterior view of the hip was taken. The pelvic pitch was measured on the X-ray. A positive pitch was defined as the caudal rotation of the upper hemipelvis. Our target abduction of the cup was 43°. We used the cup holder to guesstimate the cup abduction. In a preliminary study, we found that the weight of the cup holder increased the pelvic pitch by 5°. Thus, the target abduction of the cup holder was calculated by a formula: 43° – pelvic pitch – 5°. During the cup insertion, the cup holder was anteverted to the calculated target according to the concept of combined anteversion. We evaluated 478 THAs (429 patients), which were done with the use of the method. Results: The mean cup abduction was 43.9° (range, 32.0°–53.0°) and the mean error of cup abduction was 2.4° (standard deviation [SD], 2.0°; range, 0.0°–11.0°). The mean cup anteversion was 28.5° (range, 10.0°–42.0°) and the mean error of cup anteversion was 6.7° (SD, 5.2°; range, 0.0°–27.6°). Of all, 82.4% of the cups (394 / 478) were within the safe zone: 30°–50° abduction and 10°–35° anteversion. During 2- to 5-year follow-up, no hip dislocated. Conclusions Our adjusting method according to the pelvic pitch can be a reliable option for optimizing the cup abduction in THA.

Total joint arthroplasty (TJA) is a surgical procedure, in which parts of damaged joints are removed and replaced with a prosthesis. The main indication of TJA is osteoarthritis, and the volume of TJA is rising annually along with the increase of aged population. Hip and knee are the most common joints, in which TJAs are performed. The TJA prosthesis is composed of metal, plastic, or ceramic device. Even though TJA is the most successful treatment for end-stage osteoarthritis, it is associated with various complications, and periprosthetic joint infection (PJI) is the most serious complication after TJA. With the increasing volume of TJAs, there is a simultaneous rise in the incidence of PJI. Contamination of the surgical wound and the adherence of bacteria to the surface of prosthetic component represent the initial step in the pathogenesis of PJI. The main sources of the contamination are 1) patient's own flora, 2) droplets in the operation room air, and 3) surgical gloves and instruments. Even though modern techniques have markedly reduced the degree of contamination, TJAs cannot be done in completely germ-free conditions and some degree of contamination is inevitable in all surgical procedures. However, not all contamination leads to PJI. It develops when the burden of contamination exceeds the immune threshold or the colony forming units (CFUs) and various factors contribute to a decrease in the CFU level. Surgeons should be aware of the germ burden/CFU concept and should monitor sources of contamination to maintain the germ burden below the CFU to prevent PJI.

Background: Preoperative concerns of patients undergoing total hip arthroplasty (THA) and their complaints during the initial postoperative period are not well investigated. We evaluated preoperative concerns of patients and patient-perceived problems during the operation and initial 5 days after the operation. Methods: One hundred and thirty-two patients, who underwent primary THA at a tertiary referral hospital, were surveyed using a questionnaire and a face-to-face interview 1 day before the operation, operation day, and postoperative days 1, 2, 3, and 4. The severity of pain was assessed daily using a visual analog scale. Results: The most common preoperative concern was the severity of pain after the surgery (65.2%), followed by the need of transfusion (34.8%) and postoperative rehabilitation (32.6%). Among 29 patients who could recall the experience during the operation, 12 (41.4%) suffered from shoulder pain on the contralateral side, and 6 (20.7%) answered that hammering sound had been annoying. After returning to the ward, 29 patients (22.0%) suffered from nausea, 8 (6.1%) complained of back pain, and 7 (5.3%) had ipsilateral knee pain. On postoperative day 1, 7 patients (5.3%) had persistent back pain, 8 (6.1%) had headache, and 5 (3.8%) suffered from nausea. On postoperative day 2, nine patients (6.8%) complained of radiating pain due to aggravation of preexisting spinal stenosis, 7 (5.3%) complained of weakness of the hip flexor due to periarticular injection of ropivacaine during the operation, and 5 (3.8%) had dressing-related skin problem at the wound. On postoperative days 3 and 4, patients had no problem other than hip pain. The mean pain score was the highest (3.1 ± 1.0) on postoperative day 1. Conclusions The results of this study might provide information needed to solve problems and improve satisfaction of patients undergoing THA.

Background: Delta ceramic-on-ceramic (CoC) articulation affords excellent outcomes in primary total hip arthroplasty (THA). However, the safety and reliability of this bearing in revision THA need more evidence. This study aimed to report complications, radiological changes, clinical results, and survivorship of revision THA using Delta CoC articulation at minimum 5-year follow-up. Methods: We reviewed 118 revision THAs (113 patients: 68 men and 45 women) performed with use of Delta CoC bearing. Their mean age was 58.7 years (range, 30–90 years) and their mean body mass index was 24.6 kg/m 2 (range, 15.2–32.5 kg/m 2 ). These patients were followed up for 5–12 years (mean, 7.2 years). We evaluated squeak, grinding sensation, ceramic fracture, dislocation, periprosthetic joint infection (PJI), periprosthetic fracture, prosthetic loosening, ceramic wear, osteolysis, modified Harris hip score (mHHS), and survivorship with any reoperation after the revision as the endpoint. Results: Two patients (1.7%) had grinding sensation, but no patient had ceramic fracture. Reoperations were necessary in 9 hips (7.6%) due to PJIs in 2, stem loosening in 2, cup loosening in 2, recurrent dislocation in 2, and periprosthetic fracture in 1. No hip had measurable wear or osteolysis. The average mHHS improved from 53.3 points before the revision to 82.3 points at the final follow-up. Survivorship was 91.6% (95% confidence interval, 86.3%–96.9%) at 12 years. Conclusions The Delta ceramic bearing appeared a reliable option for revision THA, showing encouraging mid-term results with acceptable survivorship and a low complication rate.