JBJS

Of Mice and Men: Temporal Comparison of Femoral Shaft Fracture Healing After Intramedullary Nailing: Retrospective Observational Study of Modified Radiographic Union Scores for Tibia

J Bone Joint Surg Am. 2025 Jul 10;107(16):1841-1847. doi: 10.2106/JBJS.24.01304.

ABSTRACT

BACKGROUND: Researchers employ murine fracture models to study bone healing, but the temporal relationship between mouse and human fracture healing is poorly understood. The hypothesis of this study was that it was possible to quantify specific post-fracture time frames corresponding to the stages of endochondral ossification in both mice and humans.

METHODS: Radiographs of mice and human femoral fractures treated with intramedullary stabilization were reviewed. The study included 330 human femoral fractures (OTA/AO 32A, B, or C injuries) that ultimately healed without complications in patients aged 18 to 55 years and 309 surgically created midshaft femoral fractures in 3-month-old C57BL6/J mice. Multiple orthopaedic surgeons assessed the radiographs using the Modified Radiographic Union Score for Tibia (mRUST). A 4-parameter log-logistic curve was fit to describe fracture healing over time, with 3 parameters allowed to vary: Y∞ (mRUST score at time = ∞), k (healing rate in [1/log(time)]), and X0.5 (time to half-healing).

RESULTS: The values (and 95% confidence interval) for the mice were Y∞ = 14.70 (14.54 to 14.87), k = 4.54/log(days) (4.30 to 4.77), and X0.5 = 11.77 days (11.56 to 11.98). For the humans, the values were Y∞ = 16.78 (16.21 to 17.36), k = 1.37/log(days) (1.28 to 1.45), and X0.5 = 91 days (83 to 99). All parameters differed significantly between the mice and humans (p < 0.05).

CONCLUSIONS: Using mRUST scoring and mathematical modeling, we were able to quantify and compare the temporal progression of fracture healing in mice and humans.

CLINICAL RELEVANCE: These data are relevant for designing and/or interpreting fracture healing studies of mice and humans to promote rational translation of fracture research between species.

PMID:40833385 | PMC:PMC12344732 | DOI:10.2106/JBJS.24.01304

The Future Is Mobile: Pilot Validation Study of Apple Health Metrics in Orthopaedic Trauma

J Bone Joint Surg Am. 2025 Jun 4;107(16):1825-1832. doi: 10.2106/JBJS.24.00842.

ABSTRACT

BACKGROUND: Surgeons often lack objective data on patient functional outcomes, particularly as compared with the patient's baseline. The present study aimed to determine whether gait parameters recorded on Apple iPhones provided longitudinal mobility data following lower-extremity fracture surgery that matched clinical expectations. We hypothesized that iPhones would detect the mobility changes of injury and early recovery, correlate with patient-reported outcome measures, and differentiate nonunion.

METHODS: This cross-sectional study included 107 adult patients with lower-extremity fractures who owned iPhones and had at least 6 months of follow-up. Participants shared Apple Health data and completed Patient Reported Outcomes Measurement Information System (PROMIS) surveys. The primary outcome was the daily step count. Four other gait-related parameters were analyzed: walking asymmetry, double support, walking speed, and step length. Mixed-effects models compared mobility parameters at pre-injury, immediate post-injury, and 6-months post-injury time points. Correlations between mobility parameters and PROMIS surveys were assessed. A mixed-effect model evaluated the relationship between step count recovery and surgery for nonunion.

RESULTS: There was a 93% reduction in daily step count from the pre-injury period to the immediate post-injury period (95% confidence interval [CI], -94% to -93%). Other gait parameters also showed increased impairment from pre-injury to post-injury. At 6 months, step count improved sixfold relative to the immediate post-injury period but remained 52% below baseline (95% CI, -55% to -49%). PROMIS Physical Function correlated moderately with step count (r = 0.42; 95% CI, 0.25 to 0.57) and weakly with other gait parameters. Patients with a known nonunion had a 55% slower recovery of step count than those without a nonunion (95% CI: 44% to 66%).

CONCLUSIONS: Apple Health mobility parameters captured changes in mobility following lower-extremity fracture and throughout the subsequent recovery period. These metrics distinguished between patients with and without nonunions, demonstrating their potential usefulness as objective, real-world functional outcome measures. These "digital biomarkers" may aid clinical decision-making and research and could be utilized for the early identification of patients at risk for poor outcomes.

LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

PMID:40833368 | PMC:PMC12354133 | DOI:10.2106/JBJS.24.00842

Impact of Childhood Obesity on Capital Femoral Epiphysis Morphology: A Large-Scale, Automated 3D-CT Study and Potential Implications for SCFE Pathogenesis

J Bone Joint Surg Am. 2025 Aug 14. doi: 10.2106/JBJS.24.01472. Online ahead of print.

ABSTRACT

BACKGROUND: The precise pathological mechanisms through which obesity increases the risk of slipped capital femoral epiphysis (SCFE) remain unclear. We aimed to investigate the impact of childhood obesity on the morphology of the capital femoral epiphysis in children and adolescents without hip disorders.

METHODS: We performed a retrospective cross-sectional study that included 4,888 children and adolescents 7 to 19 years of age who underwent a hip or pelvic computed tomography (CT) scan, most for abdominal pain, between 2004 and 2022. Automated 3D-CT analysis assessed epiphyseal tubercle height, superior and anterior peripheral cupping, and epiphyseal tilt. Generalized additive models (GAMs) were used to examine the associations between epiphyseal morphology and age, stratified by obesity status, while adjusting for sex.

RESULTS: We observed distinct age-related trajectories of femoral-head morphology related to obesity. Subjects with obesity demonstrated a larger femoral-head diameter from ages 7 to 15 years (obese versus normal-weight differences: 0.3 to 2.3 mm), smaller epiphyseal tubercle height after 9 years of age (normal-weight versus obese differences: 0.4% to 1.3%), and a more posteriorly tilted epiphysis, as assessed by a smaller axial tilt angle (normal-weight versus obese differences: 4° to 1°) from ages 7 to 15 years. In subjects with obesity, the superior epiphyseal cupping was larger before 11 years of age (obese versus normal-weight differences: 1.6% to 0.4%), but after 13 years of age, the superior epiphyseal cupping was smaller (normal-weight versus obese differences: 0.2% to 2%).

CONCLUSIONS: Children with obesity demonstrated a smaller epiphyseal tubercle height, greater posterior epiphyseal tilt, and reduced superior cupping compared with children of normal weight. These anatomical differences may contribute to the increased risk of SCFE in patients with obesity and offer potential imaging markers for earlier identification and risk-stratification.

LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

PMID:40811524 | DOI:10.2106/JBJS.24.01472

Conversion of Fused Knees to Total Knee Arthroplasty: The 21 to 31-Year Clinical Results and Patient Satisfaction

J Bone Joint Surg Am. 2025 Aug 14. doi: 10.2106/JBJS.25.00149. Online ahead of print.

ABSTRACT

BACKGROUND: There are limited long-term data on the results of conversion of a surgically or spontaneously fused knee to a total knee arthroplasty (TKA) in the literature. The purpose of this study was to determine the long-term (minimum, 21-year) results of TKA in a fused knee.

METHODS: We reviewed the results of 95 TKAs in the fused knees of 93 patients (mean age, 41.9 ± 9.4 years; range, 23 to 62 years) using a TKA system. The mean follow-up was 25.1 years (range, 21 to 31 years).

RESULTS: The mean Knee Society score was 88 points (range, 56 to 96 points) at the final follow-up. The mean range of motion was 76.4° (range, 0° to 105°). Nine knees (9%) required revision for aseptic loosening of TKA components. One knee (1%) was revised for pyogenic infection, and another knee was revised for recurrent tuberculous infection. Approximately 80% of patients were satisfied with the TKA. Approximately 67% of patients reported that their quality of life improved greatly after TKA. Kaplan-Meier survivorship, with revision for failure as the end point, was 88.4% (95% confidence interval, 83% to 97%) at 25.1 years postoperatively.

CONCLUSIONS: Conversion of a fused knee to TKA resulted in good long-term fixation and high satisfaction.

LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

PMID:40811520 | DOI:10.2106/JBJS.25.00149

Outcomes of Extra-Articular Subtalar Arthrodesis for Valgus Deformity of the Hindfoot in Patients with Cerebral Palsy: A Radiographic and Pedobarographic Study

J Bone Joint Surg Am. 2025 Aug 14. doi: 10.2106/JBJS.24.01611. Online ahead of print.

ABSTRACT

BACKGROUND: Extra-articular subtalar arthrodesis generally has been recommended for treating severe valgus deformities of the hindfoot in patients with cerebral palsy (CP). However, it is unknown whether restricted subtalar joint motion affects the shape of the foot during continued growth in children. The purpose of the present study was to evaluate the effectiveness and longevity of extra-articular subtalar arthrodesis in ambulatory patients with spastic CP, with a specific focus on its impact on the final foot shape and plantar pressure distribution.

METHODS: The present retrospective study included 99 feet in 60 children with a mean age (and standard deviation) of 7.6 ± 2.1 years at the time of surgery and 16.6 ± 4.7 years at the latest follow-up. Radiographic changes were analyzed both during the early postoperative period and at extended follow-up. At the latest follow-up, the feet were classified into 3 categories (hindfoot valgus, neutral, or varus) on the basis of the valgus/varus index obtained from dynamic pedobarographs.

RESULTS: All radiographic parameters improved at 6 months after surgery. However, at the latest follow-up, all measurements except for the lateral talocalcaneal angle indicated overcorrection of the hindfoot valgus deformity. The overall valgus/varus index decreased from 0.54 ± 0.25 before surgery to -0.29 ± 0.35 at the latest follow-up. Five feet (5.1%) were classified as hindfoot valgus, 41 feet (41.4%) as neutral, and 53 feet (53.5%) as varus. Patients with hindfoot varus were younger at the time of surgery, and a lower anteroposterior talus-first metatarsal angle at 6 months after surgery was found to be the only significant radiographic predictor of the development of hindfoot varus. Revision procedures were performed on 22 feet (41.5%) in the varus group.

CONCLUSIONS: Extra-articular subtalar arthrodesis is associated with a high risk of progressive hindfoot varus deformity in patients with CP. Our findings highlight the need to reevaluate traditional surgical indications for correcting hindfoot valgus deformity, which have largely been based on the severity of the deformity observed on radiographs. Decision-making also should account for growth-related changes associated with restricted subtalar motion and the intraoperative position of the hindfoot and forefoot.

LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

PMID:40811496 | DOI:10.2106/JBJS.24.01611

Will Investigators Enroll Particular Subjects in a Randomized Controlled Trial?: A Mixed-Methods Study to Gauge Investigator Equipoise in a Trial of Surgery Versus Nonoperative Therapy in Subjects with Meniscal Tear and Persistent Pain Following...

J Bone Joint Surg Am. 2025 Jul 18. doi: 10.2106/JBJS.24.01575. Online ahead of print.

ABSTRACT

BACKGROUND: Clinician equipoise-indifference between treatment arms-provides an ethical foundation for clinician participation in randomized controlled trials (RCTs). In preparation for an RCT comparing arthroscopic partial meniscectomy versus enhanced nonoperative therapy for patients with a meniscal tear and knee osteoarthritis (OA) who remain symptomatic after a course of physical therapy, we conducted a mixed-methods study to assess equipoise among potential enrolling clinicians.

METHODS: Fifteen clinicians with experience managing meniscal tears assessed 29 vignettes of hypothetical patients who met trial eligibility criteria. We randomly varied 13 vignette features (e.g., age, sex, radiographic severity, tear morphology). Clinicians expressed their willingness to enroll each hypothetical patient. After polling, we recorded and transcribed a moderated discussion to document clinician thought processes. We performed a quantitative analysis to identify clinical features associated with the likelihood of enrollment and an exploratory thematic analysis of the transcribed discussion to explicate the quantitative findings.

RESULTS: The 15 orthopaedic surgeons and physician assistants assessed 29 vignettes describing hypothetical patients. Eight votes were missing, leaving 427 vignettes, of which the clinicians were willing to enroll 302 (71%) (range, 24% to 100%) in the trial. Three clinicians were willing to enroll <50% of vignettes. Clinicians were willing to enroll just 39% of vignettes with bucket-handle tears. In logistic regression analyses, a bucket-handle tear (adjusted odds ratio [aOR], 0.12; 95% confidence interval [CI], 0.04 to 0.37) and Kellgren-Lawrence 3 radiographs (aOR, 0.54; 95% CI, 0.36 to 0.82) were independently associated with clinician unwillingness to randomize. The qualitative analysis confirmed that clinicians believed that bucket-handle tears should be managed operatively, whereas combinations of greater age, severe OA, inability to walk 200 yards, and higher body mass index (BMI) pushed clinicians toward nonoperative therapy.

CONCLUSIONS: This methodology can be used to identify clinicians who should be engaged in discussions and interventions to support equipoise. It can also inform development of exclusion criteria (e.g., exclude bucket-handle tears) to increase the proportion of eligible subjects referred for enrollment.

CLINICAL RELEVANCE: Orthopedic surgeons play crucial roles in randomized controlled trials, the foundation of clinical practice guidelines, by enrolling patients from their practices. This article examines clinician equipoise, a key determinant of the willingness of clinicians to enroll eligible patients in trials.

PMID:40802780 | DOI:10.2106/JBJS.24.01575

Weight Loss Before Total Knee Arthroplasty Was Not Associated with Decreased Postoperative Risks

J Bone Joint Surg Am. 2025 Aug 11. doi: 10.2106/JBJS.25.00061. Online ahead of print.

ABSTRACT

BACKGROUND: Surgeons often recommend weight loss for patients with obesity before total knee arthroplasty (TKA). However, it is unknown whether preoperative weight loss affects outcomes. The goals of this study were to determine how many patients with obesity lost weight before TKA, to identify weight loss predictors, and to evaluate if preoperative weight loss affected postoperative outcomes.

METHODS: Among 23,726 primary TKAs performed between 2002 and 2019, we identified 3,665 patients who had a body mass index (BMI) of ≥30 kg/m2 measured 1 to 24 months before surgery and had a weight measured at surgery. The mean patient age was 68 years, and 59% of patients were female. The mean patient BMI was 36 kg/m2. Univariable linear regressions evaluated weight loss predictors. Univariable and multivariable logistic regressions and Cox proportional hazards models evaluated the impact of preoperative weight change on discharge, operative time, periprosthetic joint infections (PJIs), complications, revisions, and reoperations. The mean follow-up was 6 years.

RESULTS: Overall, 20% of patients gained ≥5 pounds (1 pound = 0.45 kg), 39% maintained weight, 17% lost 5 to <10 pounds, 15% lost 10 to <20 pounds, and 9% lost ≥20 pounds before TKA. Male patients lost slightly more weight (-4.6 pounds) than female patients (-4.3 pounds) (p = 0.05). In univariable analyses, gaining >5 pounds was associated with increased odds of extended hospital length of stay (odds ratio [OR], 1.4; p = 0.01) and risk of complications (hazard ratio [HR], 1.7; p < 0.01). Losing 10 to <20 pounds was associated with increased risks of revision (HR, 2.0; p = 0.01), PJI (HR, 3.1; p < 0.01), and complications (HR, 1.6; p = 0.03). In multivariable analyses, compared with maintaining weight, losing 10 to <20 pounds was associated with an increased risk of PJI (HR, 2.6; p = 0.01), whereas gaining >5 pounds was associated with an increased risk of complications (HR, 1.5; p = 0.03).

CONCLUSIONS: Few patients with obesity lost substantial weight before primary TKA, and reaching common preoperative weight loss goals was not associated with improved outcomes. Although a healthy weight is important for general health, weight loss before TKA may not be sufficient to improve postoperative outcomes for most patients with obesity.

LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

PMID:40788982 | DOI:10.2106/JBJS.25.00061

Behavioral Intervention to Foster Healthy Lifestyle Physical Activity After Complex Lumbar Surgery: A Randomized Controlled Trial

J Bone Joint Surg Am. 2025 Aug 8. doi: 10.2106/JBJS.24.01180. Online ahead of print.

ABSTRACT

BACKGROUND: Persistent sedentary lifestyles are prevalent after complex lumbar surgery. Inactivity often is due to habit, is not necessary, and results in both adverse general health and adverse spine health. We tested a multicomponent behavioral intervention administered in surgical practices to increase lifestyle walking after recuperation from surgery involving ≥3 lumbar levels or fusion. This analysis reports the main objective of measuring change in physical activity; subsequent analysis will address the additional objective of measuring change in disability due to lumbar pain.

METHODS: At 3 months postoperatively, patients were interviewed in person, completed the self-reported Paffenbarger Physical Activity and Exercise Index measuring energy expenditure in kcal/week from walking and total activity, and were randomized to the control or a behavioral intervention. Patients in the intervention group made a contract to increase walking and received a pedometer and information about activity benefits, followed by telephone contacts over 1 year to reinforce the intervention and assess activity change. Controls received only information about activity benefits and fewer telephone contacts to assess activity change. The primary outcome was the difference in within-patient change in kcal/week from walking (as measured by the Paffenbarger Index) from enrollment to 4 months later. Additional assessments and outcomes included changes in the total Paffenbarger Index from enrollment to 4 and 12 months and changes in the walking domain to 12 months.

RESULTS: Among 250 patients (mean age, 63 years; 53% men; 96% White patients and 6% Latino patients), 123 received the intervention and 127 were controls. The mean energy expenditure from walking increased from enrollment to 4 months for patients in the intervention group (1,437 to 2,582 kcal/week; p < 0.0001) and for controls (1,320 to 1,870 kcal/week; p < 0.0001), with a greater difference for the intervention group (1,165 compared with 600 kcal/week; p = 0.03). At 12 months, the effectiveness of the intervention was sustained (estimated effect, 588 kcal/week [95% confidence interval (CI), 119 to 1,056 kcal/week]; p = 0.01) when accounting for new events that potentially affect activity, such as another lumbar surgery (estimate, -1,396 kcal/week [95% CI, -2,116 to -676 kcal/week]; p = 0.0002) and new arthroplasty or foot or ankle surgery (estimate, -701 kcal/week [95% CI, -1,212 to -189 kcal/week]; p = 0.007). Similar results were obtained for changes in total activity. Retention in this study was 92%; 72% of all patients reported that being in the study did not affect spine symptoms, and 28% reported that being in the study made symptoms better. No adverse events were associated with the trial.

CONCLUSIONS: A behavioral intervention was effective in increasing lifestyle walking after recuperation from complex lumbar surgery. These findings support integrating counseling about physical activity into routine postoperative care in surgical practices.

LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

PMID:40779643 | DOI:10.2106/JBJS.24.01180

Minimized Medial Soft Tissue Release with Bone-Recut Adjustment Improves Short-Term Outcomes: Compared with Medial Release in Posterior-Stabilized Total Knee Arthroplasty

J Bone Joint Surg Am. 2025 Aug 7. doi: 10.2106/JBJS.24.01098. Online ahead of print.

ABSTRACT

BACKGROUND: Managing soft-tissue balance and selecting an appropriate alignment target are crucial factors in modern total knee arthroplasty (TKA). Medial soft-tissue release has been widely performed in posterior-stabilized (PS) TKA; however, recent approaches to medial structure management have been reconsidered. This retrospective study aimed to assess the effectiveness of minimizing medial structure invasion using personalized alignment (PA) with precise additional bone cutting in PS-TKA compared with conventional mechanically aligned (MA) PS-TKA.

METHODS: Overall, 188 patients who underwent PS-TKA were enrolled; propensity score matching on the basis of preoperative patient characteristics was used to ensure that the groups were similar. Additional medial soft-tissue release was performed if necessary in the MA group for inappropriate ligament balance. Adequate bone recutting, as an alternative to medial release, was performed in the PA group, permitting a maximum of 3° tibial varus alignment.

RESULTS: Additional medial soft-tissue release was performed in 33 knees (35.1%) in the MA group, whereas bone recutting was performed in 37 knees (39.4%) in the PA group. The PA group had a significantly more varus postoperative medial proximal tibial angle than the MA group (mean ± standard deviation, 89.1° ± 1.2° versus 90.3° ± 1.8°; p < 0.0001). The postoperative patient satisfaction score of the 2011 New Knee Society Score (KSS) in the PA group was significantly higher than that in the MA group (mean, 29.4 ± 6.7 versus 27.5 ± 7.3; p = 0.04). Moreover, PA with bone recutting resulted in a significantly greater postoperative extension angle (mean, -1.5° ± 3.7° versus -3.0° ± 3.5°; p = 0.02) and higher KSS patient satisfaction (30.1 ± 7.7 versus 26.7 ± 7.2; p = 0.04) compared with MA with medial release.

CONCLUSIONS: This novel surgical strategy achieved appropriate balance without excessive medial release and resulted in superior clinical outcomes in PS-TKA.

LEVELS OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

PMID:40773529 | DOI:10.2106/JBJS.24.01098

Topical Versus Systemic Tranexamic Acid to Reduce Blood Loss After Total Knee and Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

J Bone Joint Surg Am. 2025 Aug 5. doi: 10.2106/JBJS.24.01511. Online ahead of print.

ABSTRACT

BACKGROUND: Tranexamic acid (TXA) has been shown to reduce blood loss during total knee arthroplasty (TKA) and total hip arthroplasty (THA), but the most effective administration method has yet to be determined. This systematic review and meta-analysis aimed to compare topical and systemic TXA administration to reduce operative blood loss.

METHODS: MEDLINE, Embase, and Cochrane CENTRAL were screened for randomized controlled trials comparing topical and systemic TXA for patients who underwent elective TKA and THA. The primary outcome was the total volume of operative blood loss, and the secondary outcomes were postoperative transfusion requirements, hemoglobin drop, hospital length of stay, and the frequencies of the main adverse events (infections and thromboembolic events). Data pooling was performed using RStudio. Subgroup analyses compared outcomes between TKA and THA.

RESULTS: Fifty-nine randomized controlled trials with a total of 6,791 patients were included in this review. Data analysis showed no significant difference between topical and systemic TXA application in terms of total blood loss (Hedges g = 0.11; 95% confidence interval [CI], -0.04 to 0.26; I2 = 82.4%). There was also no significant difference between the 2 groups in hemoglobin drop, hospital length of stay, and transfusion requirements. Subgroup analysis showed that patients undergoing TKA who received topical TXA had a significant reduction in total blood loss (g = 0.19; 95% CI, 0.00 to 0.38; I2 = 85%; p = 0.046) compared with those who received systemic TXA.

CONCLUSIONS: Topical and systemic TXA were equally effective in reducing blood loss in the analysis in which THA and TKA were combined. However, in TKA, topical application significantly reduced blood loss compared with systemic administration, while the reverse was true in THA. Further research is still necessary to find the optimal TXA dosage and administration route.

LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

PMID:40763214 | DOI:10.2106/JBJS.24.01511

Intraoperative Bone Perfusion Assessment Using Fluorescence Imaging in a Simulated Fracture Model: Effects of Osteotomy and Periosteal Disruption on Bone Perfusion During Amputation

J Bone Joint Surg Am. 2025 Aug 5. doi: 10.2106/JBJS.24.01436. Online ahead of print.

ABSTRACT

BACKGROUND: Accurate debridement of poorly perfused bone and soft tissue is critical to reduce the risk of infection in open fracture or of recurrent fracture-related infection (FRI). However, accurate delineation of viable and nonviable tissue is difficult with current technology. The aim of this pilot study was to develop and evaluate an indocyanine green (ICG)-based dynamic contrast-enhanced fluorescence imaging (DCE-FI) strategy to provide intraoperative, objective, real-time information on bone perfusion using an osteotomy model in patients undergoing lower-extremity amputation.

METHODS: Fifteen patients who were ≥18 years of age and were undergoing lower-extremity amputation were included in this study. Perfusion-related kinetic parameters derived from DCE-FI, including maximum fluorescence intensity, ingress slope, and blood flow, were compared among 3 conditions reflecting sequentially increasing osseous damage: baseline, osteotomy (disruption of endosteal blood flow), and osteotomy plus periosteal stripping (disruption of endosteal and periosteal blood flow).

RESULTS: There were significant decreases in median values from baseline to after osteotomy alone for maximum intensity (96.2 to 58.9 relative fluorescence units [RFUs]), ingress slope (3.2 to 2.0 RFU/second), and blood flow (6.7 to 4.9 mL/min/100 g). Following osteotomy plus periosteal stripping, there were also significant decreases in median values for maximum intensity (12.0 RFU), ingress slope (0.2 RFU/s), and blood flow (0.8 mL/min/100 g). The Mann-Whitney U test confirmed a significant perfusion reduction (p < 0.001) in the tibial diaphysis due to these injuries. The areas under the curve (AUC) in the receiver operating characteristic (ROC) analysis for identifying periosteal stripping (compared with only osteotomy or no osseous damage) were 0.89 to 0.90, which were higher than the AUCs for identifying any osseous damage (osteotomy with or without periosteal stripping) compared with no damage, 0.75 to 0.82.

CONCLUSIONS: This clinical study utilizing DCE-FI for intraoperative bone perfusion assessment in orthopaedic surgery demonstrated that kinetic variables derived from DCE-FI can effectively characterize and classify degradation of bone perfusion due to osteotomy and osteotomy plus periosteal stripping.

LEVEL OF EVIDENCE: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

PMID:40763212 | DOI:10.2106/JBJS.24.01436

Cement Mantle Screws in Periprosthetic Hip Fracture Fixation Near Well-Fixed Femoral Stems May Not Impact Short-Term Femoral Stem Survivorship

J Bone Joint Surg Am. 2025 Aug 5. doi: 10.2106/JBJS.24.00920. Online ahead of print.

ABSTRACT

BACKGROUND: Vancouver Type-B1 and C periprosthetic hip fractures have traditionally been treated using single- or double-plate fixation constructs. Concern exists regarding screws within the cement mantle due to the theoretical risk of cement fracture and eventual prosthetic loosening. The aim of this study was to assess femoral stem survivorship in patients with Vancouver Type-B1 or C fractures around a well-fixed cemented femoral component who were treated with a plate construct and screws into the cement mantle. The hypothesis was that screw fixation into the cement mantle would not compromise stem fixation.

METHODS: A retrospective review was performed of patients who were consecutively, surgically treated for a periprosthetic fracture around a femoral stem by 3 surgeons, as identified through a search of records from January 1, 2007, to January 1, 2023. A total of 112 consecutive patients with Vancouver Type-B1 or C periprosthetic femoral fractures treated at our institutions were reviewed. Patients who underwent fixation using plate constructs with ≥1 screw within the cement mantle around the stem were included. Patients were followed until union, revision due to plate construct failure, or stem revision. Other complications, including alignment loss, cemented stem subsidence, radiographic stem loosening, and new cement-mantle fractures, were assessed.

RESULTS: Twenty-eight patients (19 female; 27 White or Caucasian; 3 Hispanic or Latino; mean age, 81.4 ± 8.7 years) met the inclusion criteria. Radiographic union was achieved in 26 patients (92.9%). The study included 8 (28.6%) interprosthetic fractures between a total hip arthroplasty prosthesis and a total knee arthroplasty prosthesis. The mean union time was 8.0 ± 4.6 months (range, 2.2 to 25.6 weeks). The mean follow-up duration following the index procedure was 33.3 ± 24.0 months (range, 6.1 to 86.2 months). Two nonunions occurred (7.1%), both involving plate failure. Both patients required revision of the femoral prosthesis, which was not loose at the time of reoperation. No stem subsidence or cement mantle fractures occurred during follow-up, and no revisions were performed for stem loosening.

CONCLUSIONS: Screw fixation into cement around a well-fixed stem did not contribute to stem loosening at short-term follow-up. There were no isolated femoral component revisions for cement mantle issues.

LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

PMID:40763211 | DOI:10.2106/JBJS.24.00920

Development of a Spine Surgery Center of Excellence: Rationale, Design, Implementation, and Assessment of Outcomes

J Bone Joint Surg Am. 2025 Aug 5. doi: 10.2106/JBJS.25.00031. Online ahead of print.

ABSTRACT

➢ The growing prevalence and complexity of spinal pathologies have prompted hospital systems to establish dedicated spine centers to provide personalized, high-quality patient care.➢ The Joint Commission offers Advanced Certification in Spine Surgery to recognize programs that meet rigorous, evidence-based standards of care to their patient population.➢ Designing and implementing a spine center of excellence require the identification of key stakeholders, the development of a strategic plan, the generation of evidence-based clinical protocols, and routine evaluation of program metrics.➢ Spine centers of excellence offer standardized clinical pathways involving comprehensive preoperative optimization and coordinated postoperative care, thus leading to reduced complications and improved patient satisfaction with outcomes.➢ With recent advancements in minimally invasive techniques, robotic surgery, and value-based care models, a dedicated spine program should routinely evaluate the current best clinical practices to ensure compliance with the latest evidence-based care.

PMID:40763208 | DOI:10.2106/JBJS.25.00031

The Smallest Worthwhile Effect as a Promising Alternative to the MCID in Estimating PROMs for Adult Idiopathic Scoliosis

J Bone Joint Surg Am. 2025 Aug 5. doi: 10.2106/JBJS.24.01269. Online ahead of print.

ABSTRACT

BACKGROUND: The smallest worthwhile effect (SWE) enables patients to evaluate the expected value of a treatment by weighing its benefits, risks, and costs. It has emerged as an alternative to the minimal clinically important difference (MCID) for interpreting patient-reported outcome measures (PROMs). The purposes of this study were to determine the SWE estimates and MCID thresholds in patients undergoing surgery for adult idiopathic scoliosis (AdIS) and to verify whether meeting or exceeding the SWE estimates correlates with satisfaction at a minimum of 2 years postoperatively.

METHODS: Patients with postoperative satisfaction measured at a minimum of 2 years were prospectively recruited between July 2017 and August 2022. The Scoliosis Research Society-22 revised (SRS-22r) questionnaire was preoperatively administered to estimate the SWE thresholds using the benefit-harm trade-off method. The baseline SRS-22r and the SRS-30 at a minimum of 2 years postoperatively were recorded to determine the MCID estimates using the anchor-based approach, with questions 24 to 30 of the SRS-30 used as anchors. A construct validity assessment was performed to evaluate the association between meeting or exceeding the 50th percentile of the SWE (SWE50) threshold and postoperative satisfaction (defined as a score of ≥4 on both SRS-22r satisfaction questions). Race and ethnicity data were collected from the medical records.

RESULTS: A total of 119 Asian participants (19 male and 100 female) with a mean age of 26.5 ± 7.2 years were included. The absolute SWE50 estimates for the SRS-22r were 0.8 (interquartile range [IQR], 0.6 to 1.2) for self-image, 0.0 (IQR, 0.0 to 0.2) for function, 0.0 (IQR, 0.0 to 0.6) for pain, 0.4 (IQR, 0.0 to 0.6) for mental health, and 0.4 (IQR, 0.2 to 0.6) for the total score. The MCID thresholds for the corresponding domains or total score were 0.7, 0.1, 0.1, 0.3, and 0.3, respectively. Achieving or exceeding the absolute SWE50 threshold for the total score (p < 0.001) or the self-image (chi-square, 11.3; p < 0.001), function (chi-square, 6.3; p = 0.012), or pain (chi-square, 5.7; p = 0.017) domain was significantly correlated with postoperative satisfaction at a minimum of 2 years.

CONCLUSIONS: The SWE could serve as an effective alternative to the MCID for interpreting PROMs at a minimum of 2 years postoperatively in patients with AdIS.

LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

PMID:40763206 | DOI:10.2106/JBJS.24.01269

From Asymptomatic Flatfoot to Progressive Collapsing Foot Deformity: Peritalar Subluxation Is the Main Driver of Symptoms

J Bone Joint Surg Am. 2025 Aug 4. doi: 10.2106/JBJS.24.01619. Online ahead of print.

ABSTRACT

BACKGROUND: Flatfoot, or pes planus, is a common anatomical variation marked by a reduced or absent longitudinal arch. Although it is often considered benign, the condition can progress to progressive collapsing foot deformity (PCFD), a debilitating pathology. This study aimed to identify imaging biomarkers that distinguish asymptomatic flatfoot from PCFD by comparing 3D measurements among normally aligned feet, asymptomatic flatfeet, and feet with PCFD.

METHODS: A prospective, comparative, and controlled study was conducted on 561 feet in 475 subjects: 88 control subjects with 98 normally aligned feet, 66 control subjects with 132 asymptomatic flatfeet, and 321 patients with 331 feet with symptomatic PCFD. Bilateral weight-bearing computed tomography (WBCT) scans were performed, and various 3D measurements were analyzed, focusing on hindfoot valgus (Class A deformity), midfoot and/or forefoot abduction (Class B), arch collapse (Class C), and peritalar subluxation (PTS) (Class D). Statistical analysis, including multivariable nominal regression, was used to identify significant predictors of symptoms.

RESULTS: Progressive increases in Class A, B, and C deformity parameters were observed from normally aligned feet to asymptomatic flatfeet and finally to feet with PCFD. Significant differences in PTS (Class D deformity) were found only in the comparison between the feet with PCFD and the control groups, with reduced joint coverage and increased sinus tarsi coverage, indicating extra-articular impingement. Multivariable analysis identified the minimum sinus tarsi distance as the strongest predictor of symptoms, with a threshold of 1.9 mm best distinguishing symptomatic from asymptomatic feet.

CONCLUSIONS: This study demonstrated that although hindfoot valgus, midfoot and/or forefoot abduction, and arch collapse deformities progressively increase from normal alignment to PCFD, significant subtalar joint subluxation and sinus tarsi impingement were unique to symptomatic PCFD. These findings suggest that PTS can serve as a crucial biomarker for diagnosing pathologic flatfoot (PCFD) and differentiating it from asymptomatic flatfoot. Future research should explore the predictive value of PTS biomarkers in identifying flatfoot at high risk for collapse and their impact on clinical management and surgical decision-making.

LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

PMID:40758778 | DOI:10.2106/JBJS.24.01619

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