Iliac vein variation in the sacral promontory on three-dimensional computed tomography angiography: a prospective observational study before laparoscopic sacrocolpopexy.

INTRODUCTION AND HYPOTHESIS: Venous injury may occur during exposure of the anterior longitudinal ligament at the anterior sacral promontory (SP). We aimed to quantitatively measure the extent of the vascular window (VW) in front of the SP in patients with internal iliac vein (IIV) variations using preoperative three-dimensional computed tomography angiography (3DCTA). We hypothesized that patients with IIV variations would have a narrow VW. METHODS: This prospective observational study included patients scheduled for laparoscopic sacrocolpopexy (LSC) between July 2022 and April 2023 who underwent preoperative 3DCTA. The primary endpoint was the VW measurement in the standard and variant IIV groups using 3DCTA before LSC. The secondary endpoint was the difference between the two IIV groups adjusted for age, body mass index, hypertension, and diabetes using an analysis of covariance (ANCOVA) model. Multiple regression analysis was performed to analyze the effect of factors on the distance from the SP to great vascular bifurcations. RESULTS: There were 20 cases of IIV variation (20.2%). VW was 28.8 ± 12.4 mm in the variant group and 39.6 ± 12.6 mm in the standard group (p = 0.001). In the ANCOVA model, IIV variations affected VW (coefficient, -11.8; 95% confidence interval [CI], -18.4 to -5.08, p < 0.001). Multivariate analysis revealed that the aorta-SP distance decreased with age (coefficient, -0.44; 95% CI, -0.77 to -0.11, p = 0.009). CONCLUSIONS: One in five women has a vascular variant at the SP that restricts the "safe" zone of fixation to < 3 cm.

Comparison of outcomes of laparoscopic sacrocolpopexy with concomitant supracervical hysterectomy or uterine preservation.

INTRODUCTION AND HYPOTHESIS: Sacrocolpopexy was traditionally performed for post-hysterectomy prolapse or during concurrent hysterectomy. Sacrocolpopexy outcome with uterine preservation is poorly investigated. This study compared outcomes of laparoscopic sacrocolpopexy with concurrent supracervical hysterectomy or uterine preservation. METHODS: This retrospective study compared data of patients with pelvic organ prolapse who underwent laparoscopic sacrocolpopexy with uterine preservation with the data of controls who underwent laparoscopic sacrocolpopexy with supracervical hysterectomy. We analyzed composite failure in uterine preservation versus concurrent supracervical hysterectomy (primary objective) and evaluated factors associated with the primary outcome of composite failure after laparoscopic sacrocolpopexy with preservation or supracervical hysterectomy (secondary objective). Composite failure was defined as subjective bulge symptoms, reoperation, or anatomical prolapse. Cox models indicated time to composite failure as an endpoint. RESULTS: Of 274 patients, 232 underwent laparoscopic sacrocolpopexy with supracervical hysterectomy and 42 underwent laparoscopic uterine preservation. After propensity score matching (ratio: 2, for the laparoscopic sacrocolpopexy with supracervical hysterectomy group), 56 patients (24.1%) were in the supracervical hysterectomy group and 28 (66.7%) in the uterine preservation group. All patients underwent 24 months of follow-up. The composite failure rates were 10.7% for supracervical hysterectomy and 3.6% for preservation (p=0.87). The mean estimated blood loss was 10 ml (preservation, 10.0 ml [5.0-10.0] versus supracervical hysterectomy, 10.0 ml [10.0-15.0]; p=0.007). In the Cox proportional hazards model, higher preoperative body mass index and the point Ba increased composite failure risk. CONCLUSIONS: Although not statistically significant, composite failure in the two techniques is likely clinically meaningful.

Does Augmented Reality-based Portable Navigation Improve the Accuracy of Cup Placement in THA Compared With Accelerometer-based Portable Navigation? A Randomized Controlled Trial.

BACKGROUND: Previous studies reported good outcomes of acetabular cup placement using portable navigation systems during THA. However, we are aware of no prospective studies comparing inexpensive portable navigation systems using augmented reality (AR) technology with accelerometer-based portable navigation systems in THA. QUESTIONS/PURPOSES: (1) Is the placement accuracy of the acetabular cup using the AR-based portable navigation system superior to that of an accelerometer-based portable navigation system? (2) Do the frequencies of surgical complications differ between the two groups? METHODS: We conducted a prospective, two-arm, parallel-group, randomized controlled trial involving patients scheduled for unilateral THA. Between August and December 2021, we treated 148 patients who had a diagnosis of osteoarthritis, idiopathic osteonecrosis, rheumatoid arthritis, or femoral neck fracture and were scheduled to undergo unilateral primary THA. Of these patients, 100% (148) were eligible, 90% (133) were approached for inclusion in the study, and 85% (126) were finally randomized into either the AR group (62 patients) or the accelerometer group (64 patients). An intention-to-treat analysis was performed, and there was no crossover between groups and no dropouts; all patients in both groups were included in the analysis. There were no differences in any key covariates, including age, sex, and BMI, between the two groups. All THAs were performed via the modified Watson-Jones approach with the patient in the lateral decubitus position. The primary outcome was the absolute difference between the cup placement angle displayed on the screen of the navigation system and that measured on postoperative radiographs. The secondary outcome was intraoperative or postoperative complications recorded during the study period for the two portable navigation systems. RESULTS: There were no differences between the AR and accelerometer groups in terms of the mean absolute difference in radiographic inclination angle (3° ± 2° versus 3° ± 2° [95% CI -1.2° to 0.3°]; p = 0.22). The mean absolute difference in radiographic anteversion angle displayed on the navigation screen during surgery compared with that measured on postoperative radiographs was smaller in the AR group than that in the accelerometer group (2° ± 2° versus 5° ± 4° [95% CI -4.2° to -2.0°]; p < 0.001). There were few complications in either group. In the AR group, there was one patient each with a surgical site infection, intraoperative fracture, distal deep vein thrombosis, and intraoperative pin loosening; in the accelerometer group, there was one patient each with an intraoperative fracture and intraoperative loosening of pins. CONCLUSION: Although the AR-based portable navigation system demonstrated slight improvements in radiographic anteversion of cup placement compared with the accelerometer-based portable navigation system in THA, whether those small differences will prove clinically important is unknown. Until or unless future studies demonstrate clinical advantages that patients can perceive that are associated with such small radiographic differences, because of the costs and the unquantified risks associated with novel devices, we recommend against the widespread use of these systems in clinical practice. LEVEL OF EVIDENCE: Level I, therapeutic study.

Femoral prosthesis alignment of augmented reality-assisted versus accelerometer-based navigation in total knee arthroplasty: A noninferiority analysis.

INTRODUCTION: The purpose of this study was to examine the comparative precision of the augmented reality (AR)-assisted navigation system and the accelerometer-based navigation system in total knee arthroplasty (TKA). MATERIALS AND METHODS: We performed noninferiority analysis in a retrospective cohort. The coronal alignment of femoral prosthesis was compared between 109 TKAs performed using the AR-assisted navigation system and 118 TKAs performed using the accelerometer-based navigation system. All femoral prostheses were planned to be positioned perpendicular to the mechanical axis of the femur. The primary outcome was the success rate of coronal alignment of the femoral prosthesis defined as alignment error relative to neutral alignment <3°. We calculated the noninferiority margin as 7%-points using the 95%-95 % method and also confirmed the validity of the noninferiority margin using the fixed margin method. Noninferiority would be shown if the lower boundary of the 95 % confidence interval (CI) for the between-group difference in percentage of the success rate was not less than 0.93 (i.e., 1.00 - 0.07). RESULTS: Treatment success was achieved in 104 of 109 patients (95.4 %) in the AR-assisted navigation group and 110 of 118 (93.2 %) in the accelerometer-based navigation group. The risk ratio of success between the AR-assisted navigation group versus accelerometer-based navigation group was 1.02 (95 % CI, 0.96 to 1.09): the CIs did not include the noninferiority margin of 0.93. CONCLUSION: The AR-assisted navigation system was noninferior to the accelerometer-based navigation system in terms of coronal alignment of the femoral prosthesis in TKA.

Medial patellofemoral ligament is a part of the vastus medialis obliquus and vastus intermedius aponeuroses attaching to the medial epicondyle.

PURPOSE: This study aimed to investigate the bony surface characteristic of the femoral attachment of the medial patellofemoral ligament (MPFL) and the correlation between the relevant layered structures, including muscular aponeurosis and the joint capsule, which contribute to patellofemoral joint (PFJ) stability. METHODS: The morphology of the medial aspect of the medial condyle using micro-computed tomography and analysed cortical bone thickening in 24 knees was observed. For the macroscopic and histological analyses, 21 and 3 knees were allocated, respectively. The Kruskal-Wallis one-way analysis of variance test with Dunn post hoc testing was performed for statistical analysis. RESULTS: At the level of the adductor tubercle, there were no significant differences in cortical bone thickness. At the level of the medial epicondyle (MEC), cortical bone thickness was considerably greater than that in other areas of the medial condyle (mean ± standard deviation, 0.60 ± 0.20 mm; p < 0.0001). Macroscopic analysis revealed that the deep aponeurosis of the vastus medialis obliquus and the tendinous arch of the vastus intermedius distally formed the composite membrane and adjoined to the joint capsule to firmly attach to MEC, which was located at 41.3 ± 5.7 mm posterior and 14.2 ± 3.1 mm superior to the joint cartilage. Histological analysis showed a composite membrane and adjoining capsule attached to MEC via fibrocartilage. CONCLUSION: MPFL could be interpreted as part of the deep aponeurosis of the vastus medialis obliquus (VMO) and the tendinous arch of the vastus intermedius, which combined with the joint capsule to attach to MEC. The cortical bone thickening indicated that the tensile stresses were loaded on MEC in aged cadavers. Involvement of VMO and vastus intermedius aponeuroses in restored graft of MPFL could utilise the dynamic stability of surrounding muscles to mimic a native structure.

Augmented Reality- vs Accelerometer-Based Portable Navigation System to Improve the Accuracy of Acetabular Cup Placement During Total Hip Arthroplasty in the Lateral Decubitus Position.

BACKGROUND: There have been no studies regarding the effectiveness of augmented reality (AR)-based portable navigation systems compared with accelerometer-based portable navigation systems in total hip arthroplasty (THA). METHODS: We retrospectively compared THAs performed using an AR-based portable navigation system (n = 45) and those performed using an accelerometer-based portable navigation system (n = 42). All THAs were performed with the patient in the lateral decubitus position. The primary outcome was the absolute difference between cup placement angles displayed on the navigation screen and those measured on postoperative X-ray. RESULTS: The mean absolute differences were significantly smaller in the AR-based portable navigation system group than the accelerometer-based portable navigation system group in radiographic inclination (2.5° ± 1.7° vs 4.6° ± 3.1°; 95% confidence interval 1.1°-3.2°, P < .0001). Similarly, the mean absolute differences were significantly better in the AR-based portable navigation system group in radiographic anteversion (2.1° ± 1.8° vs 6.4° ± 4.2°; 95% confidence interval 3.0°-5.7°, P < .0001). Neither hip dislocation, surgical site infection, nor other complications associated with use of the navigation system occurred in either group. CONCLUSION: The AR-based portable navigation system may provide more precise acetabular cup placement compared with the accelerometer-based portable navigation system in THA.

Uncemented total hip arthroplasty using alumina ceramic bearings at a minimum of 14 years of follow-up.

INTRODUCTION: The effectiveness of modern ceramic bearings has been well established in reducing the osteolysis associated with wear of the bearing surfaces in total hip arthroplasty (THA). However, there are limited mid- to long-term follow-up data for complications associated with ceramic bearings. MATERIALS AND METHODS: This case series analyzed 124 consecutive primary uncemented THAs in 108 patients with a mean age of 61 years using alumina ceramic-on-alumina ceramic bearing couples. Seventy THAs (56%) were evaluated at a minimum 14 years of follow-up; the mean follow-up period was 16 ± 1 years (14-20 years). Kaplan-Meier survivorship was determined with revision surgery for any reason as the end point. Complications were recorded focusing on osteolysis, ceramic fracture, and abnormal sounds until the final follow-up. Clinical data were scored according to the Merle d'Aubigne and Postel hip score at 14 years after THA. RESULTS: The survivorship was 93.5% (95% CI 86.7-97.0%) at 14-years postoperatively. Five patients (4.0%) underwent revision surgery due to instability or infection before 1-year postoperatively. Two patients (1.6%) underwent revision surgery due to ceramic liner fracture at 9- and 12-years postoperatively, respectively. There was no radiographic evidence of osteolysis. A total of 27 complications occurred: dislocations (n = 7/124), squeaking sounds (n = 3/124), clicking sounds (n = 6/124), ceramic liner fractures (n = 2/124), periprosthetic fractures (n = 4/124), deep infections (n = 2/124), transient sciatic nerve palsy (n = 2/124), and femoral stem breakage (n = 1/124). The Merle d'Aubigne and Postel hip score was 16.8 ± 1.4 points. CONCLUSIONS: The survivorship analysis demonstrates the uncemented THA using alumina ceramic bearings may provide favorable clinical outcome and can offer minimal wear at a minimum 14-year follow-up. Revision surgery was mostly required due to instability and infection in the short-term, and implant breakage in the mid- to long-term.

Medium-term outcomes 2 years after laparoscopic sacrocolpopexy: a retrospective cohort study in Japan.

This study was performed to investigate medium-term outcomes and reoperation rates after laparoscopic sacrocolpopexy (LSC). We examined 119 patients undergoing LSC for symptomatic pelvic organ prolapse (POP). The primary outcomes were subjective failure and anatomical failure at 2 years; a score ≥ 2 on question 3 of the PFDI-20 was considered to indicate subjective failure. POP-Q stage 2 or higher in any compartment was considered to indicate anatomical failure. Secondary outcomes were reoperations for POP recurrence, mesh-related complications, and stress urinary incontinence (SUI). The rates of subjective failure and anatomical failure were 4.2% (n = 5) and 9.2% (n = 11), respectively. Reoperations were needed in 13.4% (n = 16) of patients, including SUI with tape procedure in 7.5% (n = 9), POP recurrence in 4.2% (n = 5), and mesh-related complications in 1.6% (n = 2). The subjective failure rate at 2 years after LSC was acceptably low.Impact StatementWhat is already known on this subject? Laparoscopic sacrocolpopexy (LSC) has clinical efficacy equivalent to open sacrocolpopexy, and there is evidence that LSC involves less blood loss and shorter length of hospital stay. However, there is still insufficient evidence to assess medium-term outcomes after LSC in Japan.What the results of this study revealed? The findings of this study showed excellent medium-term rates of subjective failure (4.2%) and anatomical failure (8.4%) after LSC. We demonstrated that patients with persistent postoperative vaginal bulge (subjective failure) also had no improvement in postoperative urinary and colorectal symptoms. Our cohort had low rates of reoperation (13.4%) after LSC. The most common reoperations were for stress urinary incontinence (SUI) (7.5%), followed by pelvic organ prolapse (POP) recurrence (4.2%) and mesh-related complications (1.6%).What are the implications of these findings in clinical practice and/or further research? This study showed that LSC is a safe and effective treatment for POP. Comparative evaluation of anatomical outcomes and the patient's condition is required to understand the extent to which LSC positively impacts a woman's pelvic floor-related quality of life.

Postoperative indications for further surgery following post-transvaginal ProliftTM mesh repair after a two-year follow-up period: a single-centre study.

We investigated the frequency of further surgery post-artificial mesh (ProliftTM) repair of pelvic organ prolapse. In total, 257 patients who underwent ProliftTM repair were evaluated for further surgery frequency, clinical outcomes, and demographic characteristics. Thirty-eight (14.7%) patients underwent further surgery (median time to reoperation, 9.5 months; range, 6-22 months). Six (2.3%) patients underwent prolapse repair at a different (5 patients, 1.9%) or same site (1 patient, 0.3%). One underwent posterior ProliftTM repair; four, laparoscopic sacrocolpopexy; and one, vaginal hysterectomy. Eight (3.1%) underwent surgery for complications; seven (2.7%) required further surgery for mesh exposure (median, 8 months) and one (0.3%) required further surgery for mesh infection (1 month). Twenty-four (9.3%) received further surgery for stress urinary incontinence (median, 8.5 months). Despite the low frequency of further surgery post-ProliftTM repair, mesh-related complications should be considered. Careful long-term follow-up is necessary.Impact StatementWhat is already known on this subject? It is widely known that vaginal mesh is used as treatment for pelvic organ prolapse (POP). Vaginal mesh is one of the treatment options for POP. However, it received a bad reputation following reports of complications associated with its use, leading to discontinuation of vaginal mesh in many countries.What the results of this study revealed? The findings of this study show that few patients who received ProliftTM repair required further surgery. The surgeries included surgery for non-POP-related conditions; subsequent surgery for stress urinary incontinence (SUI); surgery for complications including mesh exposure and infection; primary prolapse surgery for a different site and repeat surgery; and a repeat operation for prolapse arising from the same site.What are the implications of these findings in clinical practice and/or further research? Based on the outcome of this study, transvaginal ProliftTM mesh repair is a reasonably safe and effective treatment for POP. Despite withdrawal of all mesh products from the market as instructed by the FDA, this study suggested the need to re-evaluate the role of vaginal mesh as a treatment option for POP.

Laparoscopic sacrocolpopexy for pelvic organ prolapse in the elderly: safety and outcomes.

Due to its low postoperative complication rate, vaginal surgery is the preferred intervention for pelvic organ prolapse (POP) in elderly patients. We aimed to assess outcomes and perioperative complication rates associated with laparoscopic sacrocolpopexy (LSC) in elderly women. We retrospectively reviewed the medical records of 74 consecutive patients [52 (70.3%) aged <75 years; 22 (29.7%) aged ≥75 years] with POP who underwent LSC between August 2015 and December 2017. We evaluated preoperative risks using the Charlson Comorbidity Index (CCI) and complications, using the Clavien-Dindo grading (CDG). No between-group differences were observed in CCI. CDG indicated fewer perioperative complications in patients aged >75 years. Anatomical success rates at 15 months were 95.5% and 90.4% in patients aged ≥75 and <75 years, respectively. LSC has a high anatomical correction rate and few perioperative complications regardless of age. Thus, the appropriate surgical intervention method would depend on the patient's health and comorbidities.IMPACT STATEMENTWhat is already known on this subject? Laparoscopic sacrocolpopexy (LSC) is a superior method to vaginal surgery because of its anatomical and functional outcomes, particularly regarding sexual activity.What do the results of this study add? In this single-center study with a 15-month follow-up, we demonstrated that LSC has a high anatomical correction rate and few perioperative complications regardless of age at the time of surgery. Furthermore, there was no significant difference in the rate of complications between the ≥75 and <75 years groups. Thus, LSC may be considered for women aged >75 years. However, in these elderly patients, the surgical method should be determined according to their health status and medical comorbidities.What the implications are of these findings for clinical practice and/or further research? Age should not be the basis for exclusion from laparoscopic procedures. Moreover, LSC is a suitable and valid option for elderly women with POP. As the study population consisted of a homogenous group of Japanese women, it lacks generalisability. Studies evaluating these outcomes are required in other populations.

Prognosis of Incomplete Avulsion of the Proximal Hamstring Tendon Is Determined by the Avulsion Location of the Proximal Hamstring Tendon Footprint.

OBJECTIVE: To test the hypothesis that prognosis of incomplete avulsion of the proximal hamstring tendon would be worse whether avulsion location reached the proximal part of the conjoined tendon (CJ) footprint or not. DESIGN: Retrospective chart review. SETTING: Outpatient specialty clinic. PATIENTS: We reviewed 345 consecutive athletes with hamstring injury. INTERVENTIONS: Based on magnetic resonance imaging, incomplete avulsion of the proximal hamstring tendon was divided into 2 cases according to avulsion location without (cases A) or with (cases B) avulsion of the proximal part of the CJ footprint. OUTCOME MEASURES: We compared the time until return to play, subjective outcomes, and success rate of avoiding surgery between cases. RESULTS: Incomplete avulsion of the proximal hamstring tendon was detected in 47 athletes (13.6%). Thirty-four athletes were classified as cases A, and 13 as cases B. Forty-two athletes (89.4%) were followed up until return to play. The median time from pain onset to return to play was significantly longer in cases B than in cases A (B, 39.3 weeks; A, 8.0 weeks; P = 0.00015). Subjective outcomes at return to play were significantly poorer in cases B than in cases A (P = 0.00054). Success rate of avoiding surgery were significantly poorer in cases B (55%) than in cases A (100%) (P = 0.00062). CONCLUSIONS: Incomplete avulsion of the proximal hamstring tendon was observed in 13.6% of hamstring injuries. Return to play, subjective outcomes, and success rate of avoiding surgery were significantly poorer with avulsion of the proximal part of the CJ footprint.

Comparison of tissue pharmacokinetics of esflurbiprofen plaster with flurbiprofen tablets in patients with knee osteoarthritis: A multicenter randomized controlled trial.

This open-label, multicenter, prospective, randomized controlled trial aimed to determine the effectiveness of esflurbiprofen plaster (SFPP) and flurbiprofen tablets (FPTs) on knee osteoarthritis in patients scheduled for total knee arthroplasty by comparing the transfer of esflurbiprofen and flurbiprofen to tissues and fluids. Thirty-eight patients were randomly assigned in a 1:1 ratio to receive SFPP or FPT. Both groups were then divided into four subgroups, according to whether they received the final dose of SFPP or FPT at 2, 7, 12, or 24 h before planned surgery. The primary endpoints were the esflurbiprofen concentrations in synovium, synovial fluid, and plasma. Areas under concentration-time curves (AUC0-24 h ) of esflurbiprofen were calculated for each group. Pain was assessed using a numeric rating scale (NRS) 7 days before and immediately before surgery. The AUC0-24 h in the synovium were 4401.24 and 4862.70 ng·h/g in the SFPP and FPT groups, respectively. Maximum esflurbiprofen concentrations were observed in the synovium, synovial fluids, and plasma after SFPP application for 12 h. The NRS results indicated a long-lasting effect of SFPP. The AUC of the synovial esflurbiprofen concentration of SFPP indicated that the SFPP is transferred to the synovium and synovial fluid in high concentration. The efficient deep-tissue transfer of esflurbiprofen suggests that its pharmacokinetic characteristics differ from those of conventional topical NSAIDs. This study was prospectively registered in the Japan Registry of Clinical Trials (registration number: jRCTs031180228).

The cleft sign may be an independent factor of magnetic resonance imaging findings associated with a delayed return-to-play time in athletes with groin pain.

PURPOSE: To investigate the prevalence of magnetic resonance imaging (MRI) findings and define prognostic factors of the return-to-play time in young athletes with groin pain. METHODS: A total of 1091 consecutive athletes were retrospectively screened; 651 athletes, aged 16-40 years, with pain in the groin regions were assessed using MRI. Of these athletes, 356 were included for analysing the time to return-to-play. Univariate and multiple linear regression analyses were used to determine the associations between the time to return-to-play (primary outcome variable) and the following variables: age, sex, body mass index, type of sports, Hip Sports Activity Scale, clear trauma history, and 12 MRI findings. RESULTS: Four MRI findings, including cleft sign, pubic bone marrow oedema of both the superior and inferior ramus, and central disc protrusion of the pubic symphysis, appeared together in more than 44% of the cases. The median time to return-to-play was 24.7 weeks for athletes with a cleft sign on MRI, which was significantly longer than the 11.9 weeks for athletes without the sign. The median time to return-to-play was 20.8 weeks for athletes with BMI > 24, which was significantly longer than the 13.6 weeks for athletes with BMI â‰¦ 24. In multiple linear regression analysis of 356 athletes, in whom hip-related groin pain was excluded, and who were followed-up until the return-to-play, the body mass index and cleft sign were the independent factors associated with a delayed return-to-play. In contrast, iliopsoas muscle strain and other muscle injuries were associated with a shorter return-to-play. CONCLUSIONS: Multiple MRI findings were present in almost half of all cases. Body mass index and the cleft sign were independently associated with a delayed return-to-play time in young athletes suffering from groin pain. LEVEL OF EVIDENCE: III.

Does An Augmented Reality-based Portable Navigation System Improve the Accuracy of Acetabular Component Orientation During THA? A Randomized Controlled Trial.

BACKGROUND: We developed an augmented reality (AR)-based portable navigation system in which the surgeon can view the pelvic plane and placement angle of an acetabular cup on the display of a smartphone during THA. QUESTIONS/PURPOSES: (1) Is acetabular component placement more accurate using the AR-based portable navigation system compared with the conventional freehand technique? (2) Is intraoperative measurement of placement angle more accurate when using the AR-based portable navigation system compared with a goniometer? METHODS: Forty-six patients were randomly assigned to undergo acetabular cup placement during THA using the AR-based portable navigation system (AR navigation group) or placement of a mechanical alignment guide (conventional group). All surgeries were performed with the patient in the lateral decubitus position. We compared the absolute value of the difference between the targeted placement angle and postoperative measured placement angle between the groups using two types of imaging (radiography and CT). RESULTS: In terms of radiographic inclination, the mean differences between the targeted placement angle and postoperative measured angle were smaller in the AR navigation group than in the conventional group for both radiographs and CT images (2.3° ± 1.4° versus 3.9° ± 2.4°, respectively; p = 0.009 and 1.9° ± 1.3° versus 3.4° ± 2.6°, respectively; p = 0.02). There were no differences in radiographic anteversion between the two groups. No complications were associated with the use of the AR-based portable navigation system. CONCLUSIONS: This system yielded no differences in acetabular anteversion accuracy, and no clinically important differences in acetabular inclination. Therefore, at this time we cannot recommend this device as its costs and risks cannot be justified based on the absence of a clinically meaningful difference in cup placement accuracy. Although we detected no complications, this was a small series, and this approach adds both surgical time and pins in the ilium. LEVEL OF EVIDENCE: Level I, therapeutic study.

Comparison of Early-Stage and Late-Stage Periarticular Injection for Pain Relief After Total Hip Arthroplasty: A Double-Blind Randomized Controlled Trial.

BACKGROUND: No randomized controlled trial has investigated a more optimal timing of periarticular injection for pain relief after total hip arthroplasty. METHODS: The study included 140 patients, and these patients were randomly allocated to the early-stage (periarticular injection was performed just before arthrotomy, and placebo was injected after implantation) or late-stage (placebo was injected just before arthrotomy, and periarticular injection was performed after implantation) injection groups. Other perioperative interventions were similar in all participants. The prespecified primary outcome was postoperative pain score at the recovery room. RESULTS: The visual analog scale score at the recovery room of the early-stage injection group was significantly lower than that of the late-stage injection group (30 ± 28 vs 46 ± 30 mm; 95% CI, -25 to -5 mm; P = .0022), and this difference reaches a minimal clinically important difference level of 10 mm. No differences were observed with regard to complication rate. CONCLUSION: Early-stage periarticular injection during total hip arthroplasty provided better postoperative pain relief than late-stage periarticular injection without elevating complication rate. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Midterm Outcomes and Frequency of Osteolysis of Total Hip Arthroplasty Using Cementless Modular Stem for Asian Patients.

BACKGROUND: Modular stems are useful for total hip arthroplasty (THA) in anatomically difficult dysplasia. Here, we present mean 6.8-year outcomes of cementless primary THA using S-ROM-A (modified modular stem for Asian patients) femoral prosthesis in anatomically difficult cases. METHODS: Charts of 373 patients (461 hips) undergoing THA (mean age, 58 years) were reviewed for clinical evaluation of modified Merle d'Aubigné-Postel score and Kaplan-Meier survivorship with revision for any reason as the end point. For radiographic analysis, 331 patients (412 hips) followed up for ≥5 years were included. Bearing couples were metal-on-metal (n = 145), metal-on-polyethylene (n = 120), and ceramic-on-polyethylene (n = 147). Radiography and multiplanar computed tomography were performed. RESULTS: No postoperative dislocation or deep infection occurred. Mean modified Merle d'Aubigné-Postel score improved significantly (10.9 points preoperatively, 16.7 points at last follow-up; P < .001). Cumulative 5- and 10-year stem survival rates were 100% and 84%, respectively (95% confidence interval, 75%-93%). All stems were classified as bone ingrown fixation. Osteolysis occurred in metal-on-metal (42.8%) and metal-on-polyethylene (15.8%) groups. Mean time to osteolysis was ~3 years, with no significant difference between 3 groups (P = .264). In logistic regression, lower cup inclination angle was significantly associated with osteolysis (odds ratio, 0.914; 95% confidence interval, 0.84-0.99; P = .029). CONCLUSION: S-ROM-A femoral prosthesis achieved excellent midterm fixation, and the modular system was useful in primary THA with severe deformity. Bearing couples are potentially associated with adverse reactions to metal debris. S-ROM-A with ceramic-on-polyethylene bearing couples may be an option for anatomically difficult THA.

Detection of total hip prostheses at airport security checkpoints.

BACKGROUND: There have been several reports regarding airport security checks using arched metal detectors in patients with orthopedic implants and/or joint replacement surgery. Implants of different sizes and/or materials are used in total hip arthroplasty (THA), but there have been no reports regarding differences in detection rates between different types of THA implants and materials. We examined detection rates by airport metal detectors among THA patients with different implants. METHODS: We selected 1684 patients from regular outpatients at our hospital from June to December 2016. A questionnaire elicited responses regarding usage of airplanes, flight type (domestic/international), and detection by airport metal detectors. Data were investigated according to unilateral/bilateral THA, femoral stem type, acetabular shell component diameter, femoral head diameter, and femoral head material type. RESULTS: Among 671 patients selected from those who used airplanes, 346 patients reported detection by metal detectors. Detection rates for patients with unilateral THA/domestic flights, unilateral THA/international flights, bilateral THA/domestic flights, and bilateral THA/international flights were 23% (81 of 351 patients), 56% (114 of 186 patients), 75% (140 of 204 patients), and 86% (118 of 138 patients), respectively. Logistic regression analysis indicated that the most effective explanatory variables were cup size and material type of femoral head for domestic flights, and cup size for unilateral THA/international flights. CONCLUSION: Detection rate was lowest for patients with unilateral THA/domestic flights (23%), and highest for bilateral THA/international flights (86%). Statistical analyses of implant data indicated that cup size was the most significant explanatory variable.

Intraoperative loose flexion gap may restrict postoperative knee flexion after J-curve design posterior-stabilized total knee arthroplasty.

INTRODUCTION: Although soft tissue tension during total knee arthroplasty (TKA) has been targeted to achieve equal flexion and extension gaps, such a perfect gap is not always obtained. This study was performed to investigate the impact of difference between flexion and extension gaps on postoperative knee flexion angle. MATERIALS AND METHODS: We reviewed 107 consecutive TKAs using a J-curve design posterior-stabilized prosthesis. Soft tissue tension was measured intraoperatively using an offset-type tensor under 30 lb force of joint distraction with the patella reduced. All TKAs were performed in a uniform manner including the subvastus approach and without use of a pneumatic tourniquet. We assessed the association between knee flexion angle 1 year after TKA and the difference between flexion and extension gaps using Pearson's product-moment correlation and multiple regression analysis with age, sex, body mass index, diagnosis, history of diabetes mellitus, preoperative flexion angle, and gap difference as explanatory variables. RESULTS: The difference between flexion and extension gaps showed a slight negative correlation with postoperative knee flexion angle in univariate analysis (r = - 0.20, 95% CI, - 0.38 to - 0.01, p = 0.04). Multiple regression analysis showed that the gap difference was an independent factor associated with postoperative knee flexion angle (ß = - 0.89, 95% CI, - 1.60 to - 0.18, p = 0.01). CONCLUSIONS: The difference between flexion and extension gaps was negatively correlated with postoperative knee flexion angle. Looser flexion gap compared with extension gap should be avoided in J-curve design posterior-stabilized TKA.

Percutaneous periarticular multi-drug injection at one day after total knee arthroplasty as a component of multimodal pain management: a randomized control trial.

BACKGROUND: Although intraoperative periarticular multi-drug injection has been used for postoperative pain control after total knee arthroplasty (TKA), the injection has the inherent shortcoming of limited acting time. This randomized controlled trial was performed to assess whether adding percutaneous periarticular multi-drug injection at the day following TKA would improve the postoperative pain relief. METHODS: A total of 43 participants were randomly assigned to receive additional periarticular injection at 08:30, postoperative day 1 or no additional injection. The multi-drug solution including 40 mg of methylprednisolone, 150 mg of ropivacaine, and 0.1 mg of epinephrine was infiltrated into the muscle belly of the vastus medialis. In both groups, patients were treated with intraoperative periarticular multi-drug injection and postoperative intravenous and oral nonsteroidal anti-inflammatory drugs. We did not use any narcotic pain medications postoperatively. The primary outcome was the patients' global assessment of postoperative pain at rest measured using a visual analog scale (VAS) and quantified as the area under the curve (AUC) of serial assessments until 20:00, postoperative day 5. RESULTS: The mean AUC for the postoperative pain VAS at rest was 1616 ± 1191 in patients received the additional periarticular injection versus 2808 ± 1494 in those received no injection (mean difference, - 1192; 95% confidence interval, - 2043 to - 340; p = 0.007). No wound complication or surgical site infection was observed in either groups. CONCLUSIONS: Adding percutaneous periarticular multi-drug injection at the day following TKA may provide better postoperative pain relief. Further studies are needed to confirm the safety of the percutaneous injection. TRIAL REGISTRATION: University Hospital Medical Information Network UMIN000029003 . Registered 5 September 2017.

Intra-articular tranexamic acid as an adjunct to intravenous tranexamic acid for simultaneous bilateral total knee arthroplasty: a randomized double-blind, placebo-controlled trial.

BACKGROUND: Intra-articular tranexamic acid (TXA) as an adjunct to intravenous TXA was reported to decrease perioperative blood loss during unilateral total knee arthroplasty (TKA). However, there have been no randomized controlled trials comparing intravenous versus combined intravenous and intra-articular TXA administration in patients undergoing simultaneous bilateral TKA. METHODS: We randomly assigned 77 patients with 154 involved knees undergoing simultaneous bilateral TKA to the intravenous TXA group (intra-articular placebo for each knee) or combined TXA group (1000 mg of intra-articular TXA for each knee) with 1:1 treatment allocation. In both groups, 1000 mg of TXA was given intravenously twice, just before surgery and 6 h after the initial administration. Other perioperative medications, surgical procedures, and blood management strategies were the same for all patients. The primary outcome was perioperative blood loss calculated from blood volume and change in hemoglobin from preoperative to postoperative day 3. RESULTS: Intention-to-treat analysis showed no statistically significant differences in perioperative blood loss until postoperative day 3 (1067 ± 403 mL in the intravenous TXA group vs. 997 ± 345 mL in the combined TXA group [95% CI, - 240 to 100 mL], P = 0.42). No patients required allogenic blood transfusion. The incidence of thrombotic events did not differ between groups (12% in the intravenous TXA group vs. 9% in the combined TXA group; P = 0.73). CONCLUSIONS: The addition of intra-articular TXA did not reduce perioperative blood loss in patients undergoing simultaneous bilateral TKA compared with placebo. TRIAL REGISTRATION: University Hospital Medical Information Network UMIN000026137 . Registered 14 February 2017.