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Research & Methodology

Orthopaedic research methodology and reporting quality, focusing on evidence levels in sports medicine and the prevalence of reporting bias in biological therapies.

Overview

Observational database research in orthopaedics is constrained by retrospective designs, selection bias, and incomplete follow-up, which limit generalizability and lower the level of evidence [2]. Consequently, conclusions drawn from such studies cannot be stated with high confidence [2]. While multivariable analyses remain the mainstay of observational orthopaedic research and produce useful results when paired with appropriate study designs [8], frequent unreflected changes to eligibility criteria and outcomes in final presentations compared to registered trial data further complicate interpretation [3].

Systematic reviews offer a more rigorous framework, requiring clearly stated objectives, explicit reproducible methodologies, and systematic searches to identify all eligible studies [7]. These reviews must include validity assessments, such as risk of bias evaluations, and systematic synthesis of findings [7]. To ensure utility, outcome estimation should aim to identify clinically important differences, present effect measures with confidence intervals, and minimize bias [4]. However, pooling heterogeneous, low-evidence, high-bias data leads to incorrect conclusions [6], necessitating that systematic reviews explore heterogeneity to identify literature strengths and deficiencies [6].

The STROBE Statement provides essential guidance for improving the reporting of observational studies and facilitates critical appraisal by reviewers and editors [5]. Despite these tools, clinicians maintain different sufficiency-of-proof thresholds for adopting evidence and often integrate biases and mechanistic rationale alongside high-level trials [10]. Furthermore, spin in systematic review abstracts regarding platelet-rich plasma treatment is not associated with general study characteristics or funding [13]. Emerging analytical frameworks, such as Bayesian analysis, offer potential to reduce sample sizes and recruitment costs in RCTs [14], while understanding current evidence for emerging technologies remains critical for appropriate utilization in orthopaedic trauma [15]. Reform is ultimately needed to alter clinical research approaches to produce more useful data at reduced costs [9].

Anatomy & Pathophysiology

Osseous Deformity and Alignment

Surgical management is indicated for progressive, painful, unilateral coxa vara deformity or leg-length discrepancy in childhood, whereas moderate nonprogressive coxa vara deformity in childhood often does not require surgery [27]. In total knee arthroplasty, the rotating-platform design offers no significant clinical advantage over the all-polyethylene tibial component design [30], and a prospective, randomized study demonstrated no clinical advantages of the mobile-bearing knee compared to the fixed-bearing design [48]. Computer-assisted total knee arthroplasty provides better correction of leg alignment compared with jig-based total knee arthroplasty when combined with a minimally invasive surgical approach [49].

Ligamentous Pathology and Reconstruction

Cruciate ligament injuries are common with a rising incidence, yet optimal graft locations and surgical techniques for anterior cruciate ligament (ACL) reconstruction remain areas of ongoing research [32]. Isolated posterior cruciate ligament injuries can often be managed nonsurgically [32]. At 2 years after ACL reconstruction with tibialis anterior allografts, the subject group displayed satisfactory functional outcomes [50]. There was no difference between hamstring tendon and patellar tendon ACL reconstructions regarding synovial fluid contents, suggesting a comparable biological response between these autografts [55]. Patients were able to perform sports-related functions and maintain a relatively high knee-related quality of life 10 years after ACL reconstruction, although activity levels significantly declined over time [33].

Diagnostic Methodology and Outcome Reporting

Patient-reported outcome measures and diagnostic imaging are the most frequently reported outcomes in femoroacetabular impingement syndrome research, while measures of hip strength and range of motion are underreported [11]. Current surgical outcomes for femoroacetabular impingement syndrome are limited to mid-term follow-up time frames with inconsistent reporting [11]. A careful history and effective physical examination serve as the foundation for diagnosing knee instability, but information from multiple physical tests is required to reach a final diagnosis [17]. Observed differences in knee scores between study groups not matched for clinically relevant factors likely represent differences in patient populations rather than differences in operative technique or implant design [19]. Several preoperative patient-reported outcome factors and potentially modifiable factors affect long-term knee function after anterior cruciate ligament reconstruction [20]. Objective assessment of functional abilities using tools like the DynaPort KneeTest is indispensable for daily practice and research in knee surgery [46].

Articular Cartilage and Wear Analysis

Autologous Matrix-Induced Chondrogenesis (AMIC) is an effective and safe method for treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases [16]. Computer-assisted vector wear analysis demonstrated superior repeatability and accuracy compared with current techniques of manual analysis for determining polyethylene wear in total hip replacements [54]. An artificial intelligence system enhances meniscal injury diagnosis by generating instant structured reports, facilitating faster image interpretation and reducing physician workload [53].

There was no significant benefit for gait kinematics in the early postoperative period (three months) for patients undergoing total hip arthroplasty through a minimally invasive Watson-Jones approach compared to a standard transgluteal approach [52]. The culture of orthopaedics is shifting toward an evidence-based approach, with momentum moving from questioning the lack of randomized trials to addressing clinical questions and improving trial design [21]. There has been a significant increase in the volume of systematic reviews and meta-analyses published in orthopaedic sports medicine [22].

Classification

Basic Science: Orthopaedic research encompasses biomechanics, molecular biology, and clinical management principles [1].

Observational Database Research: This methodology is constrained by retrospective design, selection bias, and incomplete follow-up [2]. These limitations restrict result generalizability, lower the level of evidence, and prevent conclusions from being stated with high confidence [2].

Reporting Standards: The STROBE Statement provides guidance to authors on improving the reporting of observational studies [5]. This framework facilitates critical appraisal and interpretation by reviewers, journal editors, and readers [5].

Systematic Reviews: A systematic review requires a clearly stated set of objectives with an explicit, reproducible methodology [7]. It necessitates a systematic search attempting to identify all studies meeting eligibility criteria [7], an assessment of the validity of included findings such as risk of bias [7], and a systematic presentation and synthesis of characteristics and findings [7]. Reviews must explore heterogeneity to identify strengths and deficiencies in current literature [6] and to guide future research [6]. Pooling heterogeneous, low-evidence, high-bias data results in incorrect conclusions [6].

Clinical Research Reform: Reform is needed to alter the approach to clinical research to produce more useful results [9]. This reform aims to produce more useful clinical research at the same or even at a massively reduced cost [9].

Evidence Adoption: Clinicians have different sufficiency-of-proof thresholds for adopting evidence [10]. They often integrate biases and mechanistic rationale alongside high-level clinical trials when making decisions [10].

Artificial Intelligence: AI and LLMs are extraordinary tools that can potentially help clinicians research and summarize topics [12]. However, they cannot be relied upon for accuracy and consistency at present [12].

Data Interpretation: Observed differences in knee scores between different study groups that have not been matched for various clinically relevant factors are at least as likely to represent differences in patient populations as they are to represent differences in operative technique or implant design [19].

Machine Learning: Building and assessing machine learning models requires a clearly identified problem [24]. These models require high-quality data [24] and continuous monitoring for clinical deployment [24].

Quantitative Indicators: Carefully selected and applied quantitative indicators can be a useful complement to other forms of evaluation and decision-making [26]. It is always a good idea to use a range of metrics appropriate to the discipline and relevant to the context in which they are being used [26].

Computational Tools: Computers should be viewed as tools to help researchers answer existing questions [36]. They should be viewed as tools to help researchers formulate better future questions rather than replacements for researchers [36].

ChatGPT Research: The scope of medical research concerning ChatGPT remains limited by a trend of redundancy [37]. Future efforts should shift toward novel, meaningful applications addressing pressing healthcare challenges [37]. These efforts should utilize structured, multidisciplinary frameworks [37].

Clinical Presentation

The foundation of diagnosing knee instability remains a careful history and effective physical examination [17], as information from multiple tests is required to reach a final diagnosis [17]. While observational database research is limited by retrospective design, selection bias, and incomplete follow-up, reducing generalizability [2], clinicians often integrate biases and mechanistic rationale alongside high-level clinical trials when determining sufficiency of proof for adoption [10]. For rare clinical syndromes where original trials are unfeasible, review articles and database mining studies remain important [18]; however, the increasing trend of such studies raises concerns about the future availability of original articles needed to conduct them [18].

Outcome estimation must aim at identifying a clinically important difference, presenting measures of effects with confidence intervals, and taking necessary steps to minimize bias [4]. Multivariable analyses serve as effective statistical tools that produce easily interpretable and useful results when used with appropriate study design [8] and will continue to be the mainstay of observational orthopaedic research [8]. Pooling heterogeneous, low-evidence, high-bias data results in incorrect conclusions [6], whereas systematic reviews should explore heterogeneity to identify strengths and deficiencies in current literature and guide future research [6].

A systematic review requires a clearly stated set of objectives with an explicit, reproducible methodology [7], a systematic search that attempts to identify all studies meeting the eligibility criteria [7], an assessment of the validity of the findings of the included studies such as through the assessment of risk of bias [7], and systematic presentation and synthesis of the characteristics and findings of the included studies [7]. The STROBE Statement provides guidance to authors on how to improve the reporting of observational studies and facilitates critical appraisal by reviewers, journal editors, and readers [5]. Changes to eligibility criteria and primary and secondary outcomes in randomized controlled trials are frequently made in the final presentation without being reflected in the registered trial data [3].

Reform is needed to alter the approach to clinical research to produce more useful results at the same or even at a massively reduced cost [9]. Bayesian analysis offers an attractive framework for the analysis of RCTs with the potential to reduce sample size, recruitment time, and cost [14]. Carefully selected and applied quantitative indicators can be a useful complement to other forms of evaluation and decision-making [26], and it is always a good idea to use a range of metrics appropriate to the discipline and relevant to the context in which they are being used [26].

Smartphone studies designed without awareness of the challenges inherent to smartphone use may fail or provide biased results [25]. AI and LLMs are extraordinary tools that can potentially help clinicians research and summarize topics but cannot be relied upon for accuracy and consistency at present [12]. AI has not yet demonstrated reproducible and efficacious results in the sports medicine literature [23], though it should be advocated for as a valuable assistant that could significantly improve diagnostic accuracy once it meets qualitative validation [23]. Building and assessing machine learning models requires a clearly identified problem, high-quality data, and continuous monitoring for clinical deployment [24].

Investigations

Other Considerations: Outcome estimation must aim to identify a clinically important difference [4] and present measures of effect with confidence intervals [4], while taking necessary steps to minimize bias [4]. Multivariable analyses serve as the mainstay of observational orthopaedic research, functioning as effective statistical tools that yield easily interpretable results when paired with appropriate study design [8]. The STROBE Statement provides guidance to authors on improving the reporting of observational studies and facilitates critical appraisal by reviewers, editors, and readers [5]. Pooling heterogeneous, low-evidence, high-bias data results in incorrect conclusions; therefore, systematic reviews should explore heterogeneity to identify strengths and deficiencies in current literature and to guide future research [6].

In femoroacetabular impingement syndrome (FAI), patient-reported outcome measures and diagnostic imaging are the most frequently reported outcomes, whereas measures of hip strength and range of motion are underreported [11]. Current surgical outcomes for FAI are limited to mid-term follow-up time frames and feature inconsistent reporting [11]. Regarding artificial intelligence and large language models (LLMs), while they are extraordinary tools that can potentially help clinicians research and summarize topics, they cannot be relied upon for accuracy and consistency at present [12]. AI has not yet demonstrated reproducible and efficacious results in the sports medicine literature, though it should be advocated for as a valuable assistant that could significantly improve diagnostic accuracy once it meets qualitative validation [23]. Understanding the current evidence and appropriate indications of emerging technologies is of critical importance for their utilization [15].

The culture of orthopaedics is slowly but clearly changing to an evidence-based approach, with momentum shifting from questioning why more randomized trials are not done to addressing what clinical questions should be addressed and how to make randomized trials better [21]. There has been a significant increase in the volume of systematic reviews and meta-analyses published in orthopaedic sports medicine [22]. However, spin in the abstracts of systematic reviews and meta-analyses on platelet-rich plasma treatment in orthopaedics was not associated with general study characteristics, including adherence to PRISMA guidelines or funding [13]. Nationwide databases offer large sample sizes and enable the investigation of trends over time, yet readers must be aware of limitations including variations in data collection, imperfections in patient sampling, insufficient follow-up, and lack of orthopaedic-specific outcomes [44]. The results of a randomized controlled trial comparing surgical and nonsurgical treatment for cervical radiculopathy will contribute to better decision making in the treatment of cervical radiculopathy [45]. An online survey among ESSKA members highlights the need for further investigation into the reasons behind the limited diffusion of the evidence-based medicine approach despite medical community interest [42].

Plain radiography: The double semitendinosus anterior cruciate ligament reconstruction procedure stabilizes the evolution of degenerative lesions as shown by standing X-ray [29].

MRI: Magnetic resonance imaging indicates that the donor site after autologous osteochondral mosaicplasty for cartilaginous lesions of the elbow joint is resurfaced with fibrous tissue [38].

CT: Radiographic methods including 3-D CT and MRI cannot be considered an accurate and reliable basis for the diagnosis and treatment of subspine impingement in FAI patients [41].

Other Considerations: Intraoperative findings of the labrum cannot be considered an accurate and reliable basis for the diagnosis and treatment of subspine impingement in FAI patients [41].

Treatment

Non-Operative

Current surgical outcomes for femoroacetabular impingement syndrome are limited to mid-term follow-up time frames with inconsistent reporting [11]. Moderate nonprogressive deformity in childhood coxa vara often does not require surgery [27]. Isolated PCL injuries can often be managed nonsurgically [32]. Treatment options for hallux rigidus and osteoarthrosis of the first metatarsophalangeal joint range from non-operative measures to various surgical procedures including cheilectomy, arthroplasty, and arthrodesis [39]. The treatment of chronic, nonradicular, discogenic low back pain remains controversial [43].

Operative

Indications: Surgical management is indicated for progressive, painful, unilateral deformity or leg-length discrepancy in childhood coxa vara [27]. Selection of treatment for hallux rigidus and osteoarthrosis of the first metatarsophalangeal joint depends on disease stage and patient factors [39]. Understanding current evidence and appropriate indications of emerging technologies is of critical importance for their utilization [15].

Surgical Approach / Technique: Double semitendinosus anterior cruciate ligament reconstruction is efficient in restoring satisfactory stability for most patients [29]. Double semitendinosus anterior cruciate ligament reconstruction stabilizes the evolution of degenerative lesions as shown by standing X-ray [29]. Optimal graft locations and surgical techniques for ACL reconstruction remain areas of ongoing research [32]. Healing indices may be useful only as a rough estimate of the duration of treatment required for each proposed procedure in distraction osteogenesis of the lower extremity [47].

Implant Selection: Measures of hip strength and range of motion are underreported in surgical outcome reporting for femoroacetabular impingement syndrome [11]. Patient-reported outcome measures and diagnostic imaging are the most frequently reported outcomes in surgical outcome reporting for femoroacetabular impingement syndrome [11]. All existing clinical studies evaluating mesenchymal stem cells for orthopaedic or sports medicine applications are limited by inadequate reporting of both preparation protocols and composition [28].

Alignment / Balancing Strategy: Multivariable analyses are effective statistical tools that produce easily interpretable and useful results when used with appropriate study design in observational orthopaedic research [8]. Outcome estimation should aim at identifying a clinically important difference, presenting measures of effects with confidence intervals, and taking steps to minimize bias [4].

Pain Management: Intradiskal electrothermal therapy shows reported therapeutic success rates of 60% to 80% for chronic, nonradicular, discogenic low back pain [43]. A more precise quantification of clinical benefits for intradiskal electrothermal therapy remains to be proved in randomized prospective trials [43].

Adjuncts: Spin in the abstracts of systematic reviews and meta-analyses on platelet-rich plasma treatment in orthopaedics was not associated with general study characteristics, including adherence to PRISMA guidelines or funding [13].

Other Considerations: Observational database research is limited by retrospective design, selection bias, and incomplete follow-up, which lowers the level of evidence and limits generalizability [2]. Changes to eligibility criteria and primary and secondary outcomes in randomized controlled trials are frequently made without being reflected in the registered trial data [3]. The STROBE Statement provides guidance to authors on how to improve the reporting of observational studies [5]. Pooling heterogeneous, low-evidence, high-bias data results in incorrect conclusions [6]. Systematic reviews should explore heterogeneity to identify strengths and deficiencies in current literature and guide future research [6]. A systematic review requires a clearly stated set of objectives with an explicit, reproducible methodology [7]. A systematic review requires a systematic search that attempts to identify all studies meeting the eligibility criteria [7]. A systematic review requires an assessment of the validity of the findings of the included studies, such as through the assessment of risk of bias [7]. A systematic review requires systematic presentation and synthesis of the characteristics and findings of the included studies [7]. Clinicians have different sufficiency-of-proof thresholds for adopting evidence, often integrating biases and mechanistic rationale alongside high-level clinical trials [10]. Bayesian analysis offers a framework for the analysis of RCTs with the potential to reduce sample size, recruitment time, and cost [14]. The culture of orthopaedics is shifting from questioning why more randomized trials are not done to addressing what clinical questions should be addressed and how to make randomized trials better [21].

Complications

Other Considerations: Observational database research is limited by retrospective design, selection bias, and incomplete follow-up, which limits generalizability and lowers the level of evidence [2]. Conclusions from these studies cannot be stated with high confidence due to limitations in study design and data quality [2]. Pooling heterogeneous, low-evidence, high-bias data results in incorrect conclusions [6]. Multivariable analyses are effective statistical tools that produce easily interpretable and useful results when used with appropriate study design, and will continue to be the mainstay of observational orthopaedic research [8]. The STROBE Statement provides guidance to authors on how to improve the reporting of observational studies [5] and facilitates critical appraisal and interpretation of studies by reviewers, journal editors, and readers [5]. Changes to eligibility criteria and primary and secondary outcomes in randomized controlled trials are frequently made but not reflected in registered trial data [3]. Outcome estimation should aim at identifying a clinically important difference [4], present measures of effects with confidence intervals [4], and take necessary steps to minimize bias [4]. Systematic reviews require a clearly stated set of objectives with an explicit, reproducible methodology [7], a systematic search that attempts to identify all studies meeting eligibility criteria [7], an assessment of the validity of findings of included studies such as through risk of bias assessment [7], and systematic presentation and synthesis of the characteristics and findings of included studies [7]. Systematic reviews should explore heterogeneity to identify strengths and deficiencies in current literature and guide future research [6]. Review articles and database mining studies are important for rare clinical syndromes where original trials are unfeasible [18], though the increasing trend of such studies raises concerns about the future availability of original articles needed to conduct them [18]. Observed differences in knee scores between study groups not matched for clinically relevant factors are at least as likely to represent differences in patient populations as differences in operative technique or implant design [19]. Implementation of technological innovation in orthopaedic surgery must become a science rather than a fashion or commercially driven process [31], and scientific follow-up and careful evaluation of patients must be guaranteed when implementing innovation in orthopaedic surgery [31]. All existing clinical studies evaluating mesenchymal stem cells for orthopaedic or sports medicine applications are limited by inadequate reporting of preparation protocols [28] and inadequate reporting of composition [28].

Instability: A careful history and effective physical examination serve as the foundation for diagnosing knee instability in orthopaedic sports medicine [17]. Information from multiple tests is required to reach a final diagnosis of knee instability [17]. A 10-year risk factor analysis identified several factors that can affect long-term knee function after ACL reconstruction [20]. Most risk factors affecting long-term knee function after ACL reconstruction are related to preoperative patient-reported outcomes and are potentially modifiable [20].

Other Considerations: AMIC is an effective and safe method of treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases [16].

Recovery

Light activity (weeks): Evidence regarding specific week ranges for light activity, such as desk work or driving, is not explicitly provided in the current evidence base for femoroacetabular impingement syndrome, anterior cruciate ligament reconstruction, or total knee arthroplasty. However, patients were able to perform sports-related functions 10 years after anterior cruciate ligament reconstruction [33], and physical recovery following femoral osteotomy for osteonecrosis of the femoral head requires an extended duration [40].

Full activity (months): Current surgical outcomes for femoroacetabular impingement syndrome are limited to mid-term follow-up time frames [11]. Patients maintained a relatively high knee-related quality of life 10 years after anterior cruciate ligament reconstruction [33], though activity levels significantly declined over time [33]. Significant improvements in functional capabilities can be achieved following femoral osteotomy for osteonecrosis of the femoral head [40].

Complete recovery / outcome plateau (months): A 10-year risk factor analysis identified several factors that can affect long-term knee function after anterior cruciate ligament reconstruction [20]. Most risk factors affecting long-term knee function after anterior cruciate ligament reconstruction are related to preoperative patient-reported outcome [20]. Most risk factors affecting long-term knee function after anterior cruciate ligament reconstruction are potentially modifiable [20]. Significant improvements in quality of life can be achieved following femoral osteotomy for osteonecrosis of the femoral head [40].

Rehabilitation protocol: Implementation of innovation in orthopaedic surgery must become a science rather than a fashion or commercially driven process [31]. Scientific follow-up and careful evaluation of patients must be guaranteed when implementing innovation in orthopaedic surgery [31]. Direct exchange for infection after total hip replacement can yield a rate of success comparable with that of delayed exchange if antibiotic-loaded cement and appropriate postoperative antibiotics are used [51].

Functional milestones: Patient-reported outcome measures are the most frequently reported outcomes in femoroacetabular impingement syndrome research [11]. Diagnostic imaging is the most frequently reported outcome in femoroacetabular impingement syndrome research [11]. Measures of hip strength are underreported in femoroacetabular impingement syndrome research [11]. Measures of range of motion are underreported in femoroacetabular impingement syndrome research [11]. Surgical outcome reporting for femoroacetabular impingement syndrome is inconsistent [11]. The Musculoskeletal Function Assessment Questionnaire was more responsive than the Short Form-36 [35]. The Musculoskeletal Function Assessment Questionnaire was more efficient in measuring changes in function between baseline and follow-up values than the Short Form-36, Western Ontario and McMaster Universities Osteoarthritis Index, and Sickness Impact Profile Health-Status Measures [35].

Other Considerations: Observational database research is limited by retrospective design, selection bias, and incomplete follow-up, which lowers the level of evidence and limits generalizability [2]. Changes to eligibility criteria and primary and secondary outcomes in randomized controlled trials are frequently made without being reflected in the registered trial data [3]. Outcome estimation should aim at identifying a clinically important difference [4]. Outcome estimation should present measures of effects with confidence intervals [4]. Outcome estimation should take necessary steps to minimize bias [4]. Autologous Matrix-Induced Chondrogenesis (AMIC) is an effective method for treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases [16]. Autologous Matrix-Induced Chondrogenesis (AMIC) is a safe method for treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases [16]. Review articles and database mining studies are important for rare clinical syndromes where original trials are unfeasible [18]. There is an increasing trend in review articles and database mining studies that raises concerns about the future availability of original articles needed to conduct such reviews [18]. Smartphone studies designed without awareness of inherent challenges may fail or provide biased results [25]. The rotating-platform design in total knee arthroplasty had no significant clinical advantage over the design with the all-polyethylene tibial component [30].

Key Evidence

  • [L5] The limitations of observational database research, including retrospective design, selection bias, and incomplete follow-up, limit the generalizability of results and lower the level of evidence, meaning conclusions cannot be stated with high confidence. (10.1016/j.jse.2016.07.002)
  • [L2] Changes are also frequently made to the final presentation of eligibility criteria and primary and secondary outcomes that are not reflected in the registered trial data. (10.1177/0363546512448363)
  • [L5] Outcome estimation should aim at identifying a clinically important difference, at presenting measures of effects with confidence intervals and at taking the necessary steps to minimize bias. (10.1302/2058-5241.3.170064)
  • [L5] The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. (10.1371/journal.pmed.0040297)
  • [L5] Pooling heterogeneous, low-evidence, high-bias data results in incorrect conclusions; instead, systematic reviews should explore heterogeneity to identify strengths and deficiencies in current literature and guide future research. (10.1016/j.arthro.2018.10.005)
  • [L5] A systematic review can be done with a clearly stated set of objectives with an explicit, reproducible methodology; a systematic search that attempts to identify all studies that would meet the eligibility criteria; an assessment of the validity of the findings of the included studies, such as through the assessment of risk of bias; and systematic presentation and synthesis of the characteristics and findings of the included studies. (10.1177/1753193415573151)
  • [L5] Multivariable analyses will continue to be the mainstay of observational orthopaedic research and are effective statistical tools that produce easily interpretable and useful results when used with appropriate study design. (10.1007/s00167-022-07215-9)
  • [L5] Reform is needed to alter the approach and produce more useful clinical research at the same or even at a massively reduced cost. (10.1371/journal.pmed.1002049)
  • [L5] The author argues that clinicians have different sufficiency-of-proof thresholds for adopting evidence, often integrating biases and mechanistic rationale alongside high-level clinical trials, and invites readers to share how they make clinical decisions. (10.1016/j.jht.2012.07.026)
  • [L4] Patient-reported outcome measures and diagnostic imaging are the most frequently reported outcomes, while measures of hip strength and range of motion are underreported, and current surgical outcomes are limited to mid-term follow-up time frames with inconsistent reporting. (10.1016/j.arthro.2017.11.037)
  • [Letter] AI and LLMs are extraordinary tools that can potentially help clinicians research and summarize topics, but they cannot be relied upon for accuracy and consistency at present. (10.1177/17531934231183224)
  • [L4] Spin was not associated with general study characteristics, including adherence to PRISMA guidelines or funding. (10.1177/23259671221137923)
  • [L5] Bayesian analysis offers an attractive framework for the analysis of RCTs, with the potential to reduce sample size and with that recruitment time and cost. (10.1177/17531934231152558)
  • [L4] AMIC is an effective and safe method of treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases. (10.1007/s00167-010-1042-3)
  • [L5] A careful history and effective physical examination continue to serve as the foundation of orthopaedic sports medicine for diagnosing knee instability, with information from multiple tests required to reach a final diagnosis. (10.1177/0363546507312641)
  • [L5] While review articles and database mining studies are important for rare clinical syndromes where original trials are unfeasible, the increasing trend raises concerns about the future availability of original articles needed to conduct such reviews. (10.1016/j.jse.2023.01.012)
  • [L4] Observed differences in knee scores between different study groups that have not been matched for various clinically relevant factors are at least as likely to represent differences in the patient populations as they are to represent differences in the operative technique or the design of the implant. (10.2106/00004623-199706000-00009)
  • [L2] This 10-year risk factor analysis identified several factors that can affect long-term knee function after ACL reconstruction, with most risk factors related to preoperative patient-reported outcome and potentially modifiable. (10.1177/0363546518788325)
  • [L2] The culture of orthopaedics is slowly but clearly changing to an evidence-based approach, with the momentum shifting from questioning why more randomized trials are not done to addressing what clinical questions should be addressed and how to make randomized trials better. (10.2106/jbjs.j.00229)
  • [L2] There has been a significant increase in the volume of systematic reviews and meta-analyses published in orthopaedic sports medicine. (10.1016/j.asmr.2021.11.013)
  • [Letter] AI has not yet demonstrated reproducible and efficacious results in the sports medicine literature, but we should be advocating for the continued use of AI as a valuable assistant that could significantly improve diagnostic accuracy once it meets qualitative validation. (10.1016/j.arthro.2021.03.013)
  • [L5] The purpose of this paper is to provide clarity and a general framework for building and assessing machine learning models, emphasizing the need for a clearly identified problem, high-quality data, and continuous monitoring for clinical deployment. (10.1007/s00167-022-07155-4)
  • [L5] If smartphone studies are designed without awareness of the challenges inherent to smartphone use, they may fail or may provide biased results. (10.1186/s12891-022-05420-8)
  • [L5] Carefully selected and applied quantitative indicators can be a useful complement to other forms of evaluation and decision-making, and it is always a good idea to use a range of metrics appropriate to your discipline and relevant to the context in which they are being used. (10.1177/17585732211058453)
  • [L5] Surgical management is indicated for progressive, painful, unilateral deformity or leg-length discrepancy, while moderate nonprogressive deformity often does not require surgery. (10.5435/00124635-199803000-00003)
  • [L1] All existing clinical studies evaluating MSCs for orthopaedic or sports medicine applications are limited by inadequate reporting of both preparation protocols and composition. (10.1177/0363546518758667)
  • [L4] The study shows that the procedure is efficient in restoring a satisfactory stability for most patients and stabilises the evolution of the degenerative lesions as shown by standing X-ray. (10.1007/s001670050076)
  • [L1] The rotating-platform design had no significant clinical advantage over the design with the all-polyethylene tibial component. (10.2106/jbjs.j.00157)
  • [L5] Implementation of innovation must become a science, not a fashion or a commercially driven process, and scientific follow-up and careful evaluation of patients must be guaranteed. (10.1007/s00167-018-4990-7)
  • [L2] Patients were able to perform sports-related functions and maintain a relatively high knee-related quality of life 10 years after ACL reconstruction, although activity levels significantly declined over time. (10.1177/0363546517749850)
  • [L3] It was more responsive than the SF-36 and more efficient in measuring changes in function between baseline and follow-up values. (10.2106/00004623-199709000-00006)
  • [L5] Computers should be viewed as tools to help researchers answer existing questions and formulate better future questions rather than replacements for researchers. (10.2106/jbjs.19.00989)
  • [L5] The scope of medical research concerning ChatGPT remains limited by a trend of redundancy; future efforts should shift toward novel, meaningful applications addressing pressing healthcare challenges through structured, multidisciplinary frameworks. (10.1016/j.arthro.2024.09.013)
  • [L4] However, magnetic resonance imaging indicates that the donor site is resurfaced with fibrous tissue. (10.1177/0363546507306465)
  • [L5] Treatment options range from non-operative measures to various surgical procedures including cheilectomy, arthroplasty, and arthrodesis, with selection depending on disease stage and patient factors. (10.2106/00004623-199806000-00015)
  • [L3] Significant improvements in quality of life and functional capabilities can be achieved following femoral osteotomy, though physical recovery requires an extended duration. (10.1016/j.arth.2025.06.066)
  • [L4] Radiographic methods including 3-D CT and MRI as well as the intraoperative findings of the labrum cannot be considered an accurate and reliable basis for the diagnosis and treatment of SSI in FAI patients. (10.1186/s12891-022-06045-7)
  • [L4] The results highlight the need for further investigation into the reasons behind the limited diffusion of the EBM approach despite medical community interest. (10.1007/s00167-019-05670-5)
  • [L5] The treatment of chronic, nonradicular, discogenic low back pain remains controversial, and while intradiskal electrothermal therapy shows reported therapeutic success rates of 60% to 80%, a more precise quantification of clinical benefits remains to be proved in randomized prospective trials. (10.5435/00124635-200301000-00003)
  • [L5] Nationwide databases offer large sample sizes and enable the investigation of trends over time, but readers must be aware of limitations including variations in data collection, imperfections in patient sampling, insufficient follow-up, and lack of orthopaedic-specific outcomes. (10.5435/jaaos-d-15-00217)
  • [L1] The outcomes of this study will contribute to better decision making in the treatment of cervical radiculopathy. (10.1186/s12891-020-3188-6)
  • [L5] Objective assessment of functional abilities using tools like the DynaPort KneeTest is indispensable for daily practice and research. (10.1007/s00167-002-0325-8)
  • [L4] Healing indices may be useful only as a rough estimate of the duration of treatment required for each proposed procedure. (10.2106/00004623-199806000-00003)
  • [L1] This prospective, randomized study did not show any clinical advantages of the mobile-bearing knee compared to the fixed-bearing design. (10.1007/s00167-010-1143-z)
  • [L3] Computer-assisted TKA gives a better correction of alignment of the leg compared with jig-based TKA when combined with a minimally invasive surgical approach. (10.1007/s00167-010-1253-7)
  • [L4] At 2 years after ACL reconstruction with tibialis anterior allografts, this subject group displayed satisfactory functional outcomes. (10.1007/s00167-003-0371-x)
  • [L4] The experience suggests that direct exchange can yield a rate of success comparable with that of delayed exchange if antibiotic-loaded cement and appropriate postoperative antibiotics are used. (10.2106/00004623-199807000-00004)
  • [L2] With regard to gait kinematics in the early postoperative period (three months), the present study showed no significant benefit for patients who underwent a total hip arthroplasty through a minimally invasive Watson-Jones approach in comparison with those who were managed with a standard transgluteal approach. (10.2106/jbjs.h.01086)
  • [L3] This artificial intelligence system enhances meniscal injury diagnosis by generating instant structured reports, facilitating faster image interpretation and reducing physician workload. (10.1002/ksa.12369)
  • [L4] Computer-assisted vector wear analysis demonstrated superior repeatability and accuracy compared with current techniques of manual analysis. (10.2106/00004623-199711000-00004)
  • [L3] However, there was no difference between HST and PT ACL reconstructions regarding synovial fluid contents, suggesting a comparable biological response between these autografts. (10.1007/s00167-003-0426-z)

See Also

References

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[2] Quantitative Observational Database Research in the Journal of Shoulder and Elbow Surgery. Journal of Shoulder and Elbow Surgery. 2016. DOI: 10.1016/j.jse.2016.07.002

[3] Publication of Sports Medicine–Related Randomized Controlled Trials Registered in ClinicalTrials.gov. The American Journal of Sports Medicine. 2012. DOI: 10.1177/0363546512448363

[4] Research methodology for orthopaedic surgeons, with a focus on outcome. EFORT Open Reviews. 2018. DOI: 10.1302/2058-5241.3.170064

[5] Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): Explanation and Elaboration. PLoS Medicine. 2007. DOI: 10.1371/journal.pmed.0040297

[6] Reviews Pooling Heterogeneous, Low‐Evidence, High‐Bias Data Result in Incorrect Conclusions: But Heterogeneity is an Opportunity to Explore. Arthroscopy. 2018. DOI: 10.1016/j.arthro.2018.10.005

[7] About systematic reviews. Journal of Hand Surgery (European Volume). 2015. DOI: 10.1177/1753193415573151

[8] Multivariable regression: understanding one of medicine’s most fundamental statistical tools. Knee Surgery, Sports Traumatology, Arthroscopy. 2022. DOI: 10.1007/s00167-022-07215-9

[9] Why Most Clinical Research Is Not Useful. PLOS Medicine. 2016. DOI: 10.1371/journal.pmed.1002049

[10] Our Sufficiency-of-Proof Thresholds. Journal of Hand Therapy. 2012. DOI: 10.1016/j.jht.2012.07.026

[11] Prevalence and Consistency in Surgical Outcome Reporting for Femoroacetabular Impingement Syndrome: A Scoping Review. Arthroscopy. 2018. DOI: 10.1016/j.arthro.2017.11.037

[12] Response to concerns about the increasing influence of artificial intelligence in publishing. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231183224

[13] Assessment of Spin in the Abstracts of Systematic Reviews and Meta-analyses on Platelet-Rich Plasma Treatment in Orthopaedics: A Cross-sectional Analysis. Orthopaedic Journal of Sports Medicine. 2023. DOI: 10.1177/23259671221137923

[14] Research methodology: the Bayesian statistical framework and the future of trial design. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231152558

[15] Chapter 3 Emerging Technologies in Orthopaedic Trauma. 2021.

[16] Mid‐term results of Autologous Matrix‐Induced Chondrogenesis for treatment of focal cartilage defects in the knee. Knee Surgery, Sports Traumatology, Arthroscopy. 2010. DOI: 10.1007/s00167-010-1042-3

[17] Current Concepts Review. The American Journal of Sports Medicine. 2008. DOI: 10.1177/0363546507312641

[18] Review articles and database studies. Journal of Shoulder and Elbow Surgery. 2023. DOI: 10.1016/j.jse.2023.01.012

[19] Demographic Biases of Scoring Instruments for the Results of Total Knee Arthroplasty. The Journal of Bone & Joint Surgery*. 1997. DOI: 10.2106/00004623-199706000-00009

[20] Ten-Year Risk Factors for Inferior Knee Injury and Osteoarthritis Outcome Score After Anterior Cruciate Ligament Reconstruction: A Study of 874 Patients From the Swedish National Knee Ligament Register. The American Journal of Sports Medicine. 2018. DOI: 10.1177/0363546518788325

[21] Clinical Trials in Orthopaedics Research. Part I. Cultural and Practical Barriers to Randomized Trials in Orthopaedics∗. Journal of Bone and Joint Surgery. 2011. DOI: 10.2106/jbjs.j.00229

[22] Declining Quality of Systematic Reviews in Orthopaedic Sports Medicine: An Updated Systematic Review. Arthroscopy, Sports Medicine, and Rehabilitation. 2022. DOI: 10.1016/j.asmr.2021.11.013

[23] Author Reply: Artificial Intelligence in Sports Medicine. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2021. DOI: 10.1016/j.arthro.2021.03.013

[24] The development and deployment of machine learning models. Knee Surgery, Sports Traumatology, Arthroscopy. 2022. DOI: 10.1007/s00167-022-07155-4

[25] Smartphones for musculoskeletal research – hype or hope? Lessons from a decennium of mHealth studies. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-05420-8

[26] Alternative research bibliometrics: It's about quality and not quantity. Shoulder & Elbow. 2022. DOI: 10.1177/17585732211058453

[27] Coxa Vara in Childhood: Evaluation and Management. Journal of the American Academy of Orthopaedic Surgeons. 1998. DOI: 10.5435/00124635-199803000-00003

[28] Reporting of Mesenchymal Stem Cell Preparation Protocols and Composition: A Systematic Review of the Clinical Orthopaedic Literature. The American Journal of Sports Medicine. 2018. DOI: 10.1177/0363546518758667

[29] Double semitendinosus anterior cruciate ligament reconstruction: 10‐year results. Knee Surgery, Sports Traumatology, Arthroscopy. 1998. DOI: 10.1007/s001670050076

[30] Mobile and Fixed-Bearing (All-Polyethylene Tibial Component) Total Knee Arthroplasty Designs. Journal of Bone and Joint Surgery. 2010. DOI: 10.2106/jbjs.j.00157

[31] Technological innovation in orthopaedic surgery: balancing innovation and science with clinical and industry interests. Knee Surgery, Sports Traumatology, Arthroscopy. 2018. DOI: 10.1007/s00167-018-4990-7

[32] Chapter 16 Cruciate Ligament Injuries. 2019.

[33] Ten-Year Outcomes and Risk Factors After Anterior Cruciate Ligament Reconstruction: A MOON Longitudinal Prospective Cohort Study. The American Journal of Sports Medicine. 2018. DOI: 10.1177/0363546517749850

[35] Comparison of the Musculoskeletal Function Assessment Questionnaire with the Short Form-36, the Western Ontario and McMaster Universities Osteoarthritis Index, and the Sickness Impact Profile Health-Status Measures. The Journal of Bone and Joint Surgery (American Volume)*. 1997. DOI: 10.2106/00004623-199709000-00006

[36] More Data Please! The Evolution of Orthopaedic Research. Journal of Bone and Joint Surgery. 2019. DOI: 10.2106/jbjs.19.00989

[37] Editorial Commentary: The Scope of Medical Research Concerning ChatGPT Remains Limited by Lack of Originality. Arthroscopy. 2024. DOI: 10.1016/j.arthro.2024.09.013

[38] Donor Site Evaluation after Autologous Osteochondral Mosaicplasty for Cartilaginous Lesions of the Elbow Joint. The American Journal of Sports Medicine. 2007. DOI: 10.1177/0363546507306465

[39] Current Concepts Review - Hallux Rigidus and Osteoarthrosis of the First Metatarsophalangeal Joint. The Journal of Bone & Joint Surgery*. 1998. DOI: 10.2106/00004623-199806000-00015

[40] A Five-Year Longitudinal Assessment of Quality of Life and Employment Status in Patients Who Have Osteonecrosis of the Femoral Head Undergoing Femoral Osteotomy: A Multicenter Study. The Journal of Arthroplasty. 2025. DOI: 10.1016/j.arth.2025.06.066

[41] A comparison between ultrasound-guided AIIS injection and radiography in the diagnosis of subspine impingement in patients with FAI. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-06045-7

[42] Evidence-Based Medicine (EBM) is properly perceived but its application is still limited in the orthopedic clinical practice: an online survey among the European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA) members. Knee Surgery, Sports Traumatology, Arthroscopy. 2019. DOI: 10.1007/s00167-019-05670-5

[43] Treatment of Chronic Discogenic Low Back Pain With Intradiskal Electrothermal Therapy. Journal of the American Academy of Orthopaedic Surgeons. 2003. DOI: 10.5435/00124635-200301000-00003

[44] Nationwide Databases in Orthopaedic Surgery Research. Journal of the American Academy of Orthopaedic Surgeons. 2016. DOI: 10.5435/jaaos-d-15-00217

[45] A randomised controlled trial comparing the effectiveness of surgical and nonsurgical treatment for cervical radiculopathy. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-3188-6

[46] Levels of analysis in knee surgery. Knee Surgery, Sports Traumatology, Arthroscopy. 2002. DOI: 10.1007/s00167-002-0325-8

[47] Distraction Osteogenesis of the Lower Extremity with Use of Monolateral External Fixation. A Study of Two Hundred and Sixty-one Femora and Tibiae. The Journal of Bone & Joint Surgery*. 1998. DOI: 10.2106/00004623-199806000-00003

[48] Mobile‐bearing prosthesis did not improve mid‐term clinical results of total knee arthroplasty. Knee Surgery, Sports Traumatology, Arthroscopy. 2010. DOI: 10.1007/s00167-010-1143-z

[49] Minimally invasive total knee arthroplasty: comparison of jig‐based technique versus computer navigation for clinical and alignment outcome. Knee Surgery, Sports Traumatology, Arthroscopy. 2010. DOI: 10.1007/s00167-010-1253-7

[50] Two‐year outcomes following ACL reconstruction with allograft tibialis anterior tendons: a retrospective study. Knee Surgery, Sports Traumatology, Arthroscopy. 2003. DOI: 10.1007/s00167-003-0371-x

[51] Direct-Exchange Arthroplasty for the Treatment of Infection after Total Hip Replacement. An Average Ten-Year Follow-up. The Journal of Bone & Joint Surgery*. 1998. DOI: 10.2106/00004623-199807000-00004

[52] Minimally Invasive Compared with Traditional Transgluteal Approach for Total Hip Arthroplasty. The Journal of Bone & Joint Surgery. 2010. DOI: 10.2106/jbjs.h.01086

[53] Achieving high accuracy in meniscus tear detection using advanced deep learning models with a relatively small data set. Knee Surgery, Sports Traumatology, Arthroscopy. 2024. DOI: 10.1002/ksa.12369

[54] Determination of Polyethylene Wear in Total Hip Replacements with Use of Digital Radiographs. The Journal of Bone and Joint Surgery (American Volume)*. 1997. DOI: 10.2106/00004623-199711000-00004

[55] Tunnel enlargement and changes in synovial fluid cytokine profile following anterior cruciate ligament reconstruction with patellar tendon and hamstring tendon autografts. Knee Surgery, Sports Traumatology, Arthroscopy. 2003. DOI: 10.1007/s00167-003-0426-z

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