J Bone Joint Surg Am. 2025 Apr 1. doi: 10.2106/JBJS.24.01406. Online ahead of print.

ABSTRACT

Adaptive learning is a powerful educational tool that uses computer algorithms to personalize and streamline an individual's learning experience. These algorithms allow for continual assessment and real-time customization of the delivery of educational content based on a specific learner's knowledge base; such algorithms mimic a 1-to-1 learning model. The current symposium describes the application of adaptive learning to orthopaedics, as well as the development of an online educational platform that utilizes this promising technology.

PMID:40168460 | DOI:10.2106/JBJS.24.01406

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.00520. Online ahead of print.

ABSTRACT

BACKGROUND: Pelvic tilt (PT) is an important sagittal parameter to be restored to the normal range in corrective surgery for spinopelvic malalignment. However, the normal value of PT varies among patients. With the introduction of the pelvic inclination angle (PIA), which is the angle subtended by the vertical axis and the line connecting the anterior pubic tubercle and the anterior superior iliac spine, we aimed to determine whether the PIA could reflect the symptom severity and whether normal PIA values exist.

METHODS: The study cohort consisted of patients with spinopelvic malalignment (patient group) and normal healthy adults (normal group). In the patient group, correlation analyses were performed to investigate the relationship between the PIA and other sagittal parameters and between the sagittal parameters and patient-reported outcome measures. In the normal group, correlation analysis was performed to assess the relationship between pelvic incidence (PI) and other sagittal parameters. The radiographic parameters were compared according to PI categories.

RESULTS: There were 162 patients in the patient group, with a mean age of 71.1 years, and 108 in the normal group, with a mean age of 32.1 years. In the patient group, the PIA strongly correlated with the conventional parameters such as PT, PI-lumbar lordosis mismatch, and T1-pelvic angle. The PIA had weak to moderate correlations with all patient-reported outcome measures, of which the correlation coefficients were similar to or greater than those of other sagittal parameters with patient-reported outcome measures. In the normal group, PI showed moderate to strong correlations with all conventional sagittal parameters except for the PIA, which correlated very weakly with PI. Unlike the other sagittal parameters, the PIA did not significantly differ among the PI categories.

CONCLUSIONS: The PIA reflected the symptom severity and had a normal value independent of PI. As an alternative to PT, the PIA can be a clinically useful parameter in evaluating and managing patients with spinopelvic malalignment.

CLINICAL RELEVANCE: As the PIA is independent of PI, it will be more useful in differentiating between patients with normal spinopelvic alignment and those with spinopelvic malalignment and in reflecting the clinical symptoms of patients with spinopelvic malalignment. In addition, by providing a cutoff value of 13.6°, the PIA can be used as a surgical target or to predict postoperative outcomes.

PMID:40153519 | DOI:10.2106/JBJS.24.00520

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.01031. Online ahead of print.

ABSTRACT

BACKGROUND: The operating room start time (ORST) for pediatric femoral fractures is a health-care quality metric used for hospital rankings and accreditation. Factors affecting ORST remain unclear. This study aimed to evaluate the demographic and clinical factors associated with gold-standard (early) ORST (<18 hours) versus delayed ORST (≥18 hours) for pediatric femoral fractures.

METHODS: A retrospective review was conducted of 216 pediatric patients with a femoral shaft fracture admitted to the emergency department (ED) at a pediatric Level-I trauma hospital from 2021 to 2023. Patient demographic and clinical data were analyzed to identify significant factors associated with ORST. Immediate postoperative outcomes were compared across ORST groups.

RESULTS: In multivariable models, race, ED admission time, comorbidities, and surgery type affected ORST (p < 0.05). Compared with White patients, patients of other racial or ethnic groups, including Hispanic, Black, Asian, and multiracial patients, had 2.4 times higher odds of delayed ORST. Compared with midnight to 6 a.m. ED admissions, the odds of delayed ORST were 6.6 times higher for ED admissions between 6 a.m. and noon and 9.2 times higher for ED admissions between noon and 6 p.m. Patients with comorbidities were 4.7 times more likely to experience delayed surgery compared with healthy patients. Patients who underwent open reduction and internal fixation (ORIF) were 2.5 times as likely as patients who underwent closed reduction (CR) with a spica cast to have delayed ORST. Delayed ORST was associated with longer hospital stay (median, 71 hours) compared with early ORST (median, 41 hours), but not with immediate complications.

CONCLUSIONS: ED admission time, race, method of transfer, comorbidities, and procedure type were associated with ORST for pediatric femoral fractures. Longer ORST led to a disproportionately longer hospital stay.

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

PMID:40153486 | DOI:10.2106/JBJS.24.01031

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.00034. Online ahead of print.

ABSTRACT

➢ Risk stratification in orthopaedic surgery is complex and depends on the outcome of interest and multiple interdependent factors. Effective risk stratification has uses for limiting and predicting adverse events in patients undergoing discretionary surgery, avoiding the penalization of surgeons for operating on candidates whose health is situated in more difficult circumstances, and ensuring that inordinate attention is not placed on discrete musculoskeletal pathophysiology when there are other pressing health priorities.➢ For individual patient decision-making, no comprehensive risk-stratification tool currently exists, in part due to the heterogeneity of orthopaedic procedures performed and the diverse patient population treated. The Elixhauser Comorbidity Measure and the Risk Stratification Index 3.0 appear to be most promising.➢ At a population level, risk stratification may be useful in alternative payment models to ensure that hospitals that treat a disproportionate number of high-risk patients are not penalized and that cherry-picking (preferentially selecting only healthier patients with a lower risk of complications) does not occur. Any attempt to risk-stratify may have unintended consequences.➢ Orthopaedic surgeons must be aware of the tools available, their strengths, and their limitations in order to be included in decision-making as payment models and public health policies are implemented.

PMID:40153485 | DOI:10.2106/JBJS.24.00034

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.01142. Online ahead of print.

NO ABSTRACT

PMID:40153484 | DOI:10.2106/JBJS.24.01142

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.00220. Online ahead of print.

ABSTRACT

BACKGROUND: Osteochondritis dissecans of the knee (KOCD) may be a source of pain in active, skeletally immature patients. An association between the condylar lesion location and lower-extremity coronal plane malalignment has been established, but clinical implications have been poorly understood. This study aimed to confirm the high rate of malalignment in KOCD and variation in demographic characteristics, presentation features, and disease severity between those with and without malalignment.

METHODS: Prospectively collected clinical, demographic, and radiographic data were obtained, and standard standing alignment measurements were evaluated from an institutional KOCD cohort. Alignment was defined as whether the mechanical axis passed between the condyles (neutral), the lateral femoral condyle (valgus), or the medial femoral condyle (varus). Comparative analysis was performed between KOCD lesions in each condyle presenting with or without malalignment. The Fisher exact test or chi-square test was used to analyze categorical variables, and the t test or Mann-Whitney U test was used to analyze continuous variables.

RESULTS: This study examined 187 knees (156 patients, with a mean age of 12.9 years, 36.4% female); 66.3% had medial femoral condyle (MFC) lesions. Malalignment was found in 47.6% of all KOCD cases and 45.9% of skeletally immature cases. Twenty-nine (23.4%) of 124 MFC KOCD cases were in varus knees, and 42 (66.7%) of 63 lateral femoral condyle (LFC) KOCD cases were in valgus knees. MFC KOCD cases that presented in varus knees were more likely in Black or African American patients (p = 0.008) and had a larger lesion size, with a coronal width of 16.6 mm compared with MFC KOCD cases not in varus knees at 14.1 mm (p = 0.008). Similar differences were found in LFC KOCD cases presenting in valgus knees, which represented nearly all LFC KOCD cases in Black or African American patients (91.7%; p = 0.05) and had a larger lesion size, with a sagittal width of 20.8 mm compared with 16.4 mm for LFC KOCD cases not in valgus knees (p = 0.006).

CONCLUSIONS: Nearly one-half of knees with KOCD in skeletally immature patients may be in coronal malalignment and, thus, candidates for guided growth. Malalignment corresponding to the involved compartment was common and was present in two-thirds of lateral lesions. When malalignment placed the weight-bearing axis within the involved compartment, lesions were larger and more advanced. Thus, consideration should be given to addressing malalignment found during evaluations.

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

PMID:40153481 | DOI:10.2106/JBJS.24.00220

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.01134. Online ahead of print.

ABSTRACT

BACKGROUND: The scarcity of women in academic orthopaedics has persisted for decades despite general interest in promoting diversity. Therefore, we aimed to understand what aspects of workplace culture enhance or detract from building an inclusive workplace for women surgeons in academic orthopaedics.

METHODS: Women orthopaedic surgeons in the United States with a range of training backgrounds, races/ethnicities, academic institutions, subspecialties, and geographic locations were recruited using purposive sampling techniques until thematic saturation was achieved. All women currently hold or previously held an academic position in orthopaedics. Forty-minute virtual semistructured interviews were conducted from December 2023 to April 2024. Data were analyzed using grounded theory methodology to develop a conceptual model of inclusive culture.

RESULTS: Of the 35 women approached for participation, 26 (74%) participated. Eighty-one percent were currently in academia, and 19% had left academia; 12% identified as Asian, and 23% identified as Underrepresented in Medicine (URiM). Our model of inclusive workplace culture is built on 2 interrelated pillars: "supportive structures" and "social inclusion." The first pillar, supportive structures, is primarily under the direction of department leaders and includes themes of intentional career development, valuing diverse contributions, transparent policies, and building department cohesiveness. The second pillar, social inclusion, relies on all members of an organization. Themes within social inclusion are respect for women, male allyship, women supporting women, and true integration of women surgeons.

CONCLUSIONS: With intentional effort, orthopaedic departments can create the structures of support necessary to foster women's career success, as well as the social inclusion to encourage their longevity in academia.

CLINICAL RELEVANCE: TK.

PMID:40153480 | DOI:10.2106/JBJS.24.01134

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.00781. Online ahead of print.

ABSTRACT

BACKGROUND: While the Femoral Neck System (FNS) is increasingly utilized for the fixation of femoral neck fractures in elderly patients, studies comparing the device to the historical standard (that is, multiple cannulated screws) are lacking. The purpose of this study was to determine the risk of all-cause revision following fixation with the FNS device compared with multiple cannulated screws in patients ≥60 years of age with a femoral neck fracture.

METHODS: Patients ≥60 years of age who underwent fixation of a femoral neck fracture with the FNS or 3 cannulated screws (2017 to 2022) were identified using the Kaiser Permanente Hip Fracture Registry. Exclusion criteria were polytrauma, pathologic fracture, open fracture, additional surgeries at other sites during the same hospital stay, and prior procedures on the affected hip. The primary outcome measure was all-cause revision surgery, and the secondary outcome measures were mortality, emergency department visits, and readmissions. Multivariable Cox proportional hazards or logistic regression was performed, controlling for a wide range of potential confounders.

RESULTS: A total of 352 FNS and 1,686 cannulated-screw repairs were included. The overall incidence of revision at 2 years was 4.0% and 4.8% for the FNS and cannulated-screw constructs, respectively. Mortality at 2 years was 23.6% and 25.2%, respectively. In the adjusted analysis, no difference in all-cause revision risk was observed when comparing the FNS to cannulated screws (hazard ratio [HR] = 0.92, 95% confidence interval [CI] = 0.50 to 1.71; p = 0.79). A subgroup analysis of procedures performed by surgeons who used both devices also did not demonstrate a difference in revision rates (HR = 0.91; 95% CI = 0.39 to 2.17; p = 0.84).

CONCLUSIONS: In this study of patients ≥60 years of age with a femoral neck fracture, the rates of all-cause revision and mortality were found to be similar between the FNS and multiple cannulated screws.

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

PMID:40153479 | DOI:10.2106/JBJS.24.00781

J Bone Joint Surg Am. 2025 Mar 28. doi: 10.2106/JBJS.24.00773. Online ahead of print.

ABSTRACT

BACKGROUND: Acupoint stimulation has been shown to reduce the risk of postoperative nausea and vomiting (PONV) after various types of surgeries involving general anesthesia, but whether the same is true after orthopaedic surgery involving spinal anesthesia is unclear. The purpose of this study was to compare PONV rates and the quality of recovery between patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) under spinal anesthesia receiving conventional antiemetics alone and those receiving antiemetics combined with use of a transcutaneous electrical acupoint stimulation bracelet (EmeTerm; WAT Medical Enterprise).

METHODS: Patients at moderate or high risk for PONV, including 195 patients undergoing THA and 153 patients undergoing TKA, were randomized to receive routine antiemetics (dexamethasone and ondansetron) alone or with use of the EmeTerm bracelet. The primary outcome was the PONV incidence within 24 hours postoperatively; secondary outcomes included the rates of severe PONV, antiemetic rescue, adverse events, and Quality of Recovery scores.

RESULTS: Combining antiemetics with the EmeTerm bracelet significantly reduced PONV (16.0% compared with 31.2%; p = 0.001), severe PONV (1.1% compared with 8.1%; p = 0.002), and antiemetic rescue (3.4% compared with 13.9%; p = 0.001). Use of the bracelet reduced the risk of PONV within 24 hours by 61% (adjusted hazard ratio, 0.39; 95% confidence interval [CI], 0.24 to 0.63), and its benefit became significant at 0 to 3 and 3 to 6-hour intervals after surgery. The complete response rate was higher for the bracelet + antiemetics group compared with the group with antiemetics alone (84.0% compared with 68.8%; p = 0.001), with better Quality of Recovery scores at 24 hours in the bracelet + antiemetics group.

CONCLUSIONS: The EmeTerm bracelet enhanced the efficacy of antiemetics in reducing PONV after THA and TKA under spinal anesthesia and may improve short-term recovery.

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

PMID:40153477 | DOI:10.2106/JBJS.24.00773

J Bone Joint Surg Am. 2025 Mar 27. doi: 10.2106/JBJS.24.01014. Online ahead of print.

ABSTRACT

BACKGROUND: Fractures are common in children, but knowledge about refractures has been limited. This study aimed to determine the rate of radiographically confirmed refractures within 2 years of the primary fracture in children and to analyze the association between fracture stability and refracture risk.

METHODS: All patients who were <16 years of age and had at least 2 fractures in the same bone between 2014 and 2023 were reviewed from the Helsinki University Hospitals' electronic pediatric treatment register, KIDS Fracture Tool. Patients' radiographs and records were evaluated. Patients with subsequent fractures in different parts of the bone than the primary fracture, patients with pathological fractures, and patients with a systemic condition predisposing to fractures were excluded.

RESULTS: Of 20,749 fractures, 163 consecutive fractures in the same bone within 2 years were identified. After exclusions, 100 cases (0.48% of all fractures) remained, with 83 occurring within 1 year and 17 occurring in the second year after the primary fracture. Refracture rates were highest in diaphyseal both-bone forearm fractures (3.76% [43 of 1,144]), diaphyseal tibial fractures (1.01% [7 of 693]), distal forearm fractures (0.55% [27 of 4,949]), and distal humeral fractures (0.49% [11 of 2,227]). The median time to refracture was 73 days (interquartile range [IQR], 56 to 131 days) for the distal forearm, 109 days (IQR, 79 to 169 days) for the diaphyseal tibia, 124 days (IQR, 80 to 178 days) for the diaphyseal forearm, and 426 days (IQR, 243 to 660 days) for the distal humerus. Displaced fractures requiring closed reduction had a significantly higher refracture risk compared with other fractures: relative risk (RR), 8.0 (95% confidence interval [CI], 4.5 to 14) compared with stable fractures; RR, 5.0 (95% CI, 2.9 to 8.7) compared with fractures that had acceptable position but might be unstable and required follow-up; and RR, 3.2 (95% CI, 1.8 to 5.7) compared with fractures requiring fixation and follow-up.

CONCLUSIONS: The overall refracture rate in children was approximately 0.5%, with the highest rates in both-bone diaphyseal forearm fractures. The median time to refracture varied significantly by anatomic location, and displaced fractures treated with closed reduction were associated with a higher refracture risk.

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

PMID:40146814 | DOI:10.2106/JBJS.24.01014

J Bone Joint Surg Am. 2025 Mar 27. doi: 10.2106/JBJS.24.00997. Online ahead of print.

ABSTRACT

➢ Musculoskeletal injuries constitute a substantial proportion of worldwide disease, with access limited to many due to the availability and cost of devices. A multifaceted approach is needed to improve system-level access to care.➢ Although a number of procurement policies are utilized, providers in low and middle-income countries often struggle with inconsistent supply chains, leading to delays in care or less desirable management strategies.➢ Partnerships between governments, academic institutions, and nongovernmental agencies are needed to improve access to devices by providing funds for patients and creating regulatory bodies to ensure product quality and availability.➢ There should be a focus on local and regional manufacturing as well as job creation within low and middle-income countries to achieve sustainable access to orthopaedic devices.➢ High-quality research initiatives are needed to provide evidence-based solutions. This includes a focus on outcomes-based studies to determine best management practices within the low and middle-income countries' context and operations research to optimize systems for device procurement.

PMID:40146811 | DOI:10.2106/JBJS.24.00997

J Bone Joint Surg Am. 2025 Mar 27. doi: 10.2106/JBJS.24.01177. Online ahead of print.

ABSTRACT

BACKGROUND: It is unclear when a patient can return to driving after total knee arthroplasty (TKA). Currently, most surgeons simply restrict all patients from driving for 4 to 6 weeks after TKA despite variability in patient age, general health, and physical capabilities. The primary objective of this study was to create novel clinical prediction calculators to estimate the return-to-driving time following primary TKA.

METHODS: In this study, 167 patients who were undergoing a primary TKA were prospectively enrolled. Subjects received text message surveys every third day postoperatively to determine when they returned to driving. Subjects completed 8 physical performance maneuvers at their 2, 6, and 12-week postoperative clinical appointments. Additionally, subjects completed return-to-driving surveys and a structured interview. Data on demographic characteristics, operative factors, patient-reported outcomes, and patient factors were collected. Cox proportional hazard and parametric survival models were utilized to create 2 novel calculators for predicting return-to-driving time.

RESULTS: There were 156 patients (mean age, 67.7 years [range, 39 to 83 years]) who completed the study. The median return-to-driving time was 18 days (interquartile range [IQR], 12 to 27 days). Univariate analysis demonstrated that male patients returned to driving sooner (18 days) than female patients (25.3 days) (p < 0.001) and that patients who underwent left-sided surgery returned to driving sooner (20.1 days) than patients who underwent right-sided surgery (24.4 days) (p = 0.021). For preoperative factors, age, sex, laterality, and preoperative Knee injury and Osteoarthritis Outcome Score (KOOS) had an effect on return-to-driving time and therefore were included in the novel preoperative clinical prediction calculator. For postoperative factors, age, sex, laterality, preoperative KOOS, and 6 metrics from the physical performance maneuvers had an effect on return-to-driving time and therefore were included in the novel postoperative physical performance-based instrument.

CONCLUSIONS: Overall, patients undergoing primary TKA returned to driving considerably earlier than previously reported. Patient-related factors and postoperative physical performance significantly affect return-to-driving time. Using the novel preoperative clinical prediction tool, individual patients can be advised when to expect to return to driving. After surgery, the novel postoperative physical performance-based instrument can inform patients when they may be ready to return to driving.

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

PMID:40146809 | DOI:10.2106/JBJS.24.01177

J Bone Joint Surg Am. 2025 Mar 27. doi: 10.2106/JBJS.24.00779. Online ahead of print.

ABSTRACT

BACKGROUND: Age-related osteoporosis complicates rotator cuff tear (RCT) treatment, undermining the integrity of surgical anchor fixation during rotator cuff repair (RCR). This study aimed to investigate whether supplementation with glutamine, an intrinsic amino acid crucial in cell metabolism, can enhance rotator cuff healing by ameliorating age-associated osteoporosis.

METHODS: Forty-eight female Sprague-Dawley rats were divided into 4 groups: (1) young control (sham surgery), (2) aged control (sham surgery), (3) aged-RCT (RCR with fibrin), and (4) aged-RCT-Gln (RCR with glutamine-enriched fibrin). RCR was performed bilaterally on rats in the RCT groups, with subsequent application of the respective fibrin gel at the tendon-bone interface. Evaluations included micro-computed tomography (CT) for bone quality, histology and immunohistochemistry for tissue integrity, and biomechanical testing for tendon-bone complex strength.

RESULTS: Micro-CT revealed worse bone quality at the proximal humerus in the aged rats compared with the young rats, confirming spontaneous osteoporosis occurring with age. Glutamine supplementation improved bone quality in the aged-RCT-Gln group compared with the aged-RCT group, with significantly higher mean bone volume/total volume fraction (BV/TV) (28.69% ± 3.1% compared with 21.13% ± 3.9%), trabecular number (Tb.N) (1.88 ± 0.18 compared with 1.55 ± 0.21 mm-1), and trabecular thickness (Tb.th) (0.15 ± 0.03 compared with 0.12 ± 0.02 mm) and lower trabecular separation (Tb.sp) (0.19 ± 0.03 compared with 0.22 ± 0.03 mm). Histological and immunohistological analysis demonstrated enhanced bone regeneration and a more organized tendon-cartilage-bone interface in the aged-RCT-Gln group. Biomechanical analysis also revealed a more resilient tendon-bone complex after glutamine supplementation.

CONCLUSIONS: Osteoporosis occurred spontaneously at the proximal humerus with age. Glutamine supplementation effectively mitigated age-related osteoporosis and enhanced RCR in elderly rats. These findings support the potential of glutamine, the most abundant amino acid in the body, as a valuable therapeutic intervention for improving RCT outcomes in the aging population, warranting further investigation in clinical settings.

CLINICAL RELEVANCE: Glutamine supplementation may be a novel therapeutic strategy to enhance RCR in elderly patients with osteoporosis.

PMID:40146808 | DOI:10.2106/JBJS.24.00779

J Bone Joint Surg Am. 2025 Mar 27. doi: 10.2106/JBJS.24.00867. Online ahead of print.

ABSTRACT

BACKGROUND: Idiopathic scoliosis (IS) is the most common spinal deformity and is often accompanied by abnormal respiratory function.

METHODS: This study investigated the correlations among radiographic parameters, pulmonary function tests, and sleep-breathing monitoring in patients with IS. The clinical data of patients with IS admitted to our hospital for scoliosis surgery between January 2020 and March 2022 were retrospectively collected. Radiographic measurements, including scoliosis and thoracic malformation parameters, were performed. Pulmonary function measurements and sleep-breathing monitoring results were collected for correlation analysis.

RESULTS: Overall, 19.8% of the 81 participants were diagnosed with obstructive sleep apnea. The sleep-breathing monitoring results showed a significant correlation between the main thoracic curvature and the lowest oxygen saturation (SpO2) (r = -0.233; p = 0.036). The degree of thoracic kyphosis significantly correlated with FEV1/FVC (forced expiratory volume in 1 second/forced vital capacity) and FEV1. FEV1 was significantly correlated with the oxygen desaturation index (ODI) (r = -0.242; p = 0.03), as was FVC.

CONCLUSIONS: In this study, 19.8% of the patients with thoracic IS had obstructive sleep apnea. In patients with IS, the severity of pulmonary function decline and SpO2 during sleep-breathing correlated with the severity of thoracic scoliosis, whereas the decline in pulmonary function correlated with the ODI during sleep-breathing.

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

PMID:40146806 | DOI:10.2106/JBJS.24.00867

J Bone Joint Surg Am. 2025 Mar 26. doi: 10.2106/JBJS.24.00423. Online ahead of print.

ABSTRACT

BACKGROUND: The aim of this study was to determine whether preserving a normal-appearing long head of the biceps (LHB) tendon leads to better Constant-Murley scores (CMS) than releasing it in patients undergoing arthroscopic repair of an isolated stage-1 supraspinatus tendon tear.

METHODS: Patients (40 to 70 years old) who were undergoing arthroscopic repair of a minor supraspinatus tendon tear and who had a macroscopically normal LHB were randomized to LHB preservation or LHB release during a prospective clinical trial. The surgeon was free to choose whether to perform tenodesis in patients undergoing LHB release. The primary outcome was the involved shoulder's function based on the absolute CMS score at 6 and 24 months. Secondary outcomes included the American Shoulder and Elbow Surgeons (ASES) shoulder score and Subjective Shoulder Value (SSV). A post-hoc analysis of prospectively collected data was done using 1:1 propensity score matching without replacement. This resulted in 2 age- and sex-matched groups of 95 patients each. Race and ethnicity data were not collected.

RESULTS: At 24 months, the mean CMS was significantly better in the LHB release group (mean and standard deviation, 86.8 ± 8.3) than in the LHB preservation group (82.9 ± 10.0) (p = 0.003), 97% of the patients in the LHB release group and 88% in the LHB preservation group had more than the minimal clinically important difference (MCID) for the CMS in rotator cuff repair (p = 0.048), 15% in the LHB preservation group and 3% in the LHB release group (p = 0.01) had an absolute CMS below 70, and the ASES was significantly higher in the LHB release group (91.4 ± 19.2) than in the LHB preservation group (83.6 ± 25.0) (p = 0.02). There were 4 reoperations in the LHB preservation group and no reoperations in the LHB release group.

CONCLUSIONS: Based on our findings, a macroscopically normal-appearing biceps tendon should be released when treating stage-1 supraspinatus tendon tears.

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

PMID:40138461 | DOI:10.2106/JBJS.24.00423

J Bone Joint Surg Am. 2025 Mar 26. doi: 10.2106/JBJS.24.01334. Online ahead of print.

NO ABSTRACT

PMID:40138442 | DOI:10.2106/JBJS.24.01334

J Bone Joint Surg Am. 2025 Mar 24. doi: 10.2106/JBJS.24.00299. Online ahead of print.

ABSTRACT

BACKGROUND: Highly porous metaphyseal cones have emerged as a promising fixation strategy to address extensive proximal tibial bone loss in the multiply revised knee. Despite a paucity of literature regarding stacked cone constructs, they have gained popularity. This study reports on the early outcomes of stacked tibial cone constructs that are used during revision total knee arthroplasty (TKA).

METHODS: A single-institution retrospective observational study was performed to identify patients who had been treated with a stacked cone construct during revision TKA between January 2010 and December 2022. Demographic, operative, clinical, and radiographic data were collected and assessed. Kaplan-Meier estimates were used to assess survival with all-cause reoperation, tibial-sided revision, and radiographic loosening as end points. In total, 22 stacked cone constructs were identified: 15 (68.2%) of the patients were men; the demographics included a mean age of 64.1 years (range, 42.8 to 87.8 years), a body mass index of 34.2 kg/m2 (range, 20.4 to 51.9 kg/m2), a median of 4 prior surgeries (range, 1 to 12 prior surgeries), and a mean follow-up of 22.6 months (range, 6.8 to 79.1 months).

RESULTS: Twenty patients received 2-cone constructs, and 2 patients received 3-cone constructs. Patients received the stacked cone constructs during revision TKA for the following indications: periprosthetic joint infection (n = 11), aseptic loosening (n = 9), tibial stem pain (n = 1), and periprosthetic fracture (n = 1). At a median time of 2.9 months (range, 0.4 to 37.3 months), 5 patients underwent reoperation for the following indications: extensor mechanism failure (n = 2), femoral component loosening (n = 1), superficial wound dehiscence (n = 1), and postoperative hematoma (n = 1). At the 3-year follow-up, no patients had undergone revision for tibial component loosening (1 patient had radiographic evidence of loosening at the 15-month follow-up but did not undergo revision).

CONCLUSIONS: Stacked cone constructs are a viable option during revision TKA when extensive metaphyseal bone loss is encountered.

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

PMID:40127133 | DOI:10.2106/JBJS.24.00299

J Bone Joint Surg Am. 2025 Mar 22. doi: 10.2106/JBJS.24.00311. Online ahead of print.

ABSTRACT

BACKGROUND: Delayed bone healing is common in orthopaedic clinical care. Agents that alter cell function to enhance healing would change treatment paradigms. 4-aminopyridine (4-AP) is a U.S. Food and Drug Administration (FDA)-approved drug shown to improve walking in patients with chronic neurological disorders. We recently showed 4-AP's positive effects in the setting of nerve, wound, and even combined multi-tissue limb injury. Here, we directly investigated the effects of 4-AP on bone fracture healing, where differentiation of mesenchymal stem cells into osteoblasts is crucial.

METHODS: All animal experiments conformed to the protocols approved by the Institutional Animal Care and Use Committee at the University of Arizona and Pennsylvania State University. Ten-week-old C57BL/6J male mice (22 to 28 g), following midshaft tibial fracture, were assigned to 4-AP (1.6 mg/kg/day, intraperitoneal [IP]) and saline solution (0.1 mL/mouse/day, IP) treatment groups. Tibiae were harvested on day 21 for micro-computed tomography (CT), 3-point bending tests, and histomorphological analyses. 4-AP's effect on human bone marrow mesenchymal stem cell (hBMSC) and human osteoblast (hOB) cell viability, migration, and proliferation; collagen deposition; matrix mineralization; and bone-forming gene/protein expression analyses was assessed.

RESULTS: 4-AP significantly upregulated BMP2 gene and protein expression and gene expression of RUNX2, OSX, BSP, OCN, and OPN in hBMSCs and hOBs. 4-AP significantly enhanced osteoblast migration and proliferation, collagen deposition, and matrix mineralization. Radiographic and micro-CT imaging confirmed 4-AP's benefit versus saline solution treatment in mouse tibial fracture healing (bone mineral density, 687.12 versus 488.29 mg hydroxyapatite/cm3 [p ≤ 0.0021]; bone volume/tissue volume, 0.87 versus 0.72 [p ≤ 0.05]; trabecular number, 7.50 versus 5.78/mm [p ≤ 0.05]; and trabecular thickness, 0.08 versus 0.06 mm [p ≤ 0.05]). Three-point bending tests demonstrated 4-AP's improvement of tibial fracture biomechanical properties versus saline solution (stiffness, 27.93 versus 14.30 N/mm; p ≤ 0.05). 4-AP also increased endogenous BMP2 expression and matrix components in healing callus.

CONCLUSIONS: 4-AP increased the healing rate, biomechanical properties, and endogenous BMP2 expression of tibiae following fracture.

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

PMID:40120116 | DOI:10.2106/JBJS.24.00311

J Bone Joint Surg Am. 2025 Mar 20. doi: 10.2106/JBJS.24.00160. Online ahead of print.

ABSTRACT

BACKGROUND: Magnetic intramedullary lengthening nails (MILNs) have become an increasingly popular method for long-bone distraction osteogenesis as a means of overcoming the limitations of bone lengthening with an external fixator. While factors such as nail diameter, alignment, and other mechanical characteristics have been associated with an increased risk of nail breakage, the relationship between the percentage of maximum lengthening utilized and nail breakage remains unexplored. We specifically assessed overall complications, with and without the inclusion of contractures, based on the amount of distraction (25% to 60%, 61% to 90%, and 91% to 100% of maximum).

METHODS: We retrospectively reviewed the records for 176 pediatric patients and 109 adult patients who had undergone limb lengthening and had ≥24 months of follow-up. The cohort was further stratified by the amount of distraction: 25% to 60% (n = 75 children and 30 adults), 61% to 90% (n = 72 children and 29 adults), and 91% to 100% (n = 29 children and 50 adults). The mean ages were 14.53, 13.53, and 12.49 years, respectively, in the pediatric cohorts and 27.1, 34.3, and 23.8 years, respectively, in the adult cohorts. The percentages of males and females were 48% vs. 52%, 54.2% vs. 45.8%, and 48.3% vs 51.7%, respectively, in the pediatric cohorts and 56.7% vs. 43.3%, 51.8% vs. 48.2%, and 58% vs. 42% in the adult cohorts. Complications included contractures, loss of length, bone fracture, axial deviation, nail failure, failure to lengthen, nail fracture/failure, and screw failure. Analysis of variance (ANOVA) was conducted to compare mean complications across the 3 distraction categories, and Tukey pairwise t tests were performed to compare mean complications between individual distraction categories.

RESULTS: Without contractures, complication rates were similar between the pediatric cohorts (p = 0.09): 4.0% (25% to 60% distraction), 13.9% (61% to 90% distraction), and 6.9% (91% to 100% distraction). With contractures included, complication rates were greatest in the 61% to 90% pediatric cohort (38.9%), followed by the 91% to 100% cohort (27.6%) and the 25% to 60% cohort (13.3%) (p = 0.002). Similarly, the adult population had a homogeneous rate of complications without the inclusion of contractures (p = 0.13). Likewise, we observed a similarly variable distribution with contractures considered, with the greatest frequency in the 91% to 100% group (36%), followed by the 61% to 90% group (31%) and the 25% to 60% group (10%) (p = 0.04).

CONCLUSIONS: This is the first study to explore the relationship between the percentage of nail lengthening and nail complications. The speculation that full extension of the nail could lead to increased nail bending or breakage was not consistent with our findings. This finding was consistent whether contractures were included or not.

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

PMID:40112087 | DOI:10.2106/JBJS.24.00160

J Bone Joint Surg Am. 2025 Mar 20. doi: 10.2106/JBJS.24.00266. Online ahead of print.

ABSTRACT

BACKGROUND: Total knee arthroplasty (TKA) is one of the most commonly performed elective procedures in North America. While advancements have been made in patient optimization, surgical technique, and implant design, tourniquet use remains a contentious issue as it relates to patient outcomes and postoperative experience.

METHODS: As part of the PEPPER trial, we identified 5,684 patients who underwent primary TKA, of whom 4,866 (85.6%) underwent surgery with a tourniquet (the YT group) and 818 (14.4%) underwent surgery without a tourniquet (the NT group). The cohort was predominantly female (60.8%), White (77%), and of an ethnicity other than Hispanic or Latino (96.8%). The mean age of the patients was 64.6 ± 9.2 years. The primary outcomes were the Knee injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS JR); Patient-Reported Outcomes Measurement Information System Physical Health Summary (PROMIS-PH10); and numeric pain rating scale (NPRS), which were captured preoperatively and at 1, 3, and 6 months postoperatively. The secondary outcomes were length of stay, discharge disposition, analgesic consumption, and postoperative complications. Multivariable analysis was performed to assess the associations between tourniquet use and patient-reported outcome measures (PROMs) following TKA.

RESULTS: The percentages of patients achieving the minimal clinically important difference (MCID) for the KOOS JR were significantly different at 1 month only (YT, 55.4%; NT, 47.9%). This difference disappeared at 3 and 6 months. There was no difference between the YT and NT groups in terms of the percentage of patients achieving the MCID for the PROMIS-PH10 or NPRS at any time point. There were no differences between the YT and NT groups at any time point with respect to the KOOS JR, PROMIS-PH10, and NPRS. There were no differences in opioid consumption, operative time, length of stay, wound-related complications, or readmissions postoperatively.

CONCLUSIONS: Tourniquet use was associated with more patients achieving the MCID for the KOOS JR at 1 month compared with no tourniquet use. This difference disappeared at 3 and 6 months. At 1, 3, and 6 months, there were no differences in opioid consumption, health-care utilization, or complications between patients undergoing TKA with a tourniquet versus without a tourniquet. Tourniquet use did not have a clinically meaningful impact on PROMs in the multivariable analysis. Arthroplasty surgeons may use these data during preoperative discussions with patients regarding tourniquet use as it relates to the surgeon's preference and how it could influence postoperative function.

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

PMID:40112083 | DOI:10.2106/JBJS.24.00266