Journal of Experimental Orthopaedics最新文献

Purpose

Conventional techniques (medial collateral ligament + posterior oblique ligament reconstructions), such as those by Lind and LaPrade, do not fully restore native knee stability in severe medial injuries. This study aimed to determine the optimal tibial insertion site for an anteromedial (AM) reconstruction strand mimicking the deep medial collateral ligament (dMCL), to better control anteromedial rotatory instability (AMRI) in knees with complete medial injury (sMCL + dMCL + POL).

Methods

Twenty fresh-frozen cadaveric knees (13 female, 7 male donors; mean age: 80 years) were tested using Dyneelax® static laximeter at 30° of flexion. After standardised transections of the superficial MCL (sMCL), deep MCL (dMCL), and posterior oblique ligament (POL), each knee was reconstructed using a trifid flat graft including an AM strand. Knees were assigned to two groups based on the tibial insertion angle (α) between the AM strand and the sMCL: group α ≤ 20° (anatomical reconstruction) and group α > 20° (oblique isometric reconstruction). Anterior tibial translation (ATT), internal rotation (IR), and external rotation (ER) were measured under 200 N of force and 5 N-m torques. Residual laxities were calculated in both absolute and relative terms, compared to the intact state, and analysed using ANOVA and Student's t-tests.

Results

Both reconstruction techniques significantly reduced laxity compared to the transected state. However, group α > 20° showed significantly lower residual laxity for ATT (0.74 ± 0.58 mm vs. 1.30 ± 0.56 mm, p = 0.04) and for ER (0.35 ± 0.39° vs. 1.05 ± 0.89°, p = 0.04), with no significant difference for IR (p = 0.24).

Conclusion

There is a trend toward better stability with a more oblique AM strand, which must be confirmed by further biomechanical studies. This trifid flat graft approach more accurately replicates the biomechanical function of the dMCL and anteromedial capsule, and could provide a refined strategy for reconstructing severe medial knee instability

Level of Evidence

Level V, experimental cadaveric study.

Purpose

To compare the anterior tibial translation (ATT) between single-bundle (SB) and double-bundle (DB) ‘supra’-over-the-top anterior cruciate ligament reconstruction (s-OTT ACLR) during the anterior drawer test in a cadaveric model.

Methods

This was a controlled laboratory study. Seven fresh-frozen cadaveric knee specimens and a robotic testing system were used. Initially, the same testing procedure (100 N anterior drawer load applied at 0°, 15°, 30°, 60° and 90° of knee flexion) was applied to the following four different knee conditions: intact, anterior cruciate ligament (ACL)-sectioned, SB s-OTT ACLR and DB s-OTT ACLR knees. Subsequently, a combined load of 5 Nm internal tibial torque and 10 Nm valgus torque was applied at 15° and 30° of knee flexion as a simulated pivot shift. During the tests, anterior tibial translation (ATT) was recorded. The initial tension was set at 22 N for the SB s-OTT ACLR and 11 N for each graft in the DB s-OTT ACLR at 30° of knee flexion. For the SB s-OTT ACLR with an 8-mm-diameter tibial tunnel, the drilling area was 16 Π mm² (4 × 4 × Π). Regarding the DB s-OTT ACLR with two 5-mm-diameter tibial tunnels, the total drilling area was 12.5 Π mm² (2.5 × 2.5 × Π × 2).

Results

Both SB and DB s-OTT ACL reconstructions significantly reduced ATT compared with the ACL-sectioned state under both anterior drawer and simulated pivot-shift loads, while showing no difference from the intact knee. No significant ATT difference was detected between SB and DB s-OTT ACLRs at any tested flexion angle, and DB achieved anterior knee stability comparable to SB despite its lower initial graft tension.

Conclusions

DB s-OTT ACLR demonstrated ATT and in situ graft force comparable to SB s-OTT ACLR in a cadaveric robotic study. These findings suggest that DB s-OTT ACLR can achieve anterior knee stability similar to SB s-OTT ACLR with lower initial graft tension.

Level of Evidence

N/A.

Purpose

Increasing attention has been directed towards the fragility index (FI) and reverse fragility index (RFI) in orthopaedic surgery. The purpose of this study was to amalgamate the FI and RFI literature in orthopaedic surgery, and critically appraise its clinical impact.

Methods

Three databases were searched from inception to 22 March 2025, for articles evaluating either the FI or RFI across orthopaedic surgery. Median and mean FI and RFI were presented as ranges with median values. Findings from correlation analyses assessing the impact of study characteristics on FI were consolidated. Citation analysis was performed to assess the uptake of FI/RFI literature.

Results

Eighty-four studies were included in the final analysis. Sports medicine was the most represented subspeciality (25.0%). Median FI of subspeciality-specific studies ranged from 1 to 6, and RFI from 3 to 7. Median FI of pathology-specific studies ranged from 0 to 12, and RFI from 2 to 10. The RFI exceeded the FI in most pathology-specific studies (93.3%). Decreasing p-value (88%), increasing sample size (50%) and increasing study power (50%) were commonly found to be associated with increasing fragility index. The median number of citations was 11.5 (interquartile range [IQR], 3.0–27.0) with a median citation density of 3.1 (IQR, 1.2–6.2). Sports medicine publications had the highest collective median citation density of 4.3 (IQR, 1.0–6.6). The h-index for all included studies was 25, indicating 25 studies had at least 25 citations. Earlier publication year (p < 0.001) and increasing journal impact factor (p = 0.007) were associated with increased citations.

Conclusion

The majority of fragility index research is concentrated across a few orthopaedic subspecialties with redundant findings indicating low statistical robustness. Recurring methodologic recommendations based on correlation analyses include increasing patient sample size to increase study power. Methodological recommendations from this body of research should be integrated into future original studies to strengthen statistical robustness.

Level of Evidence

Level III.

Purpose

High tibial osteotomy (HTO) is frequently used to treat knee malalignment in younger patients. Given the rise in online health information-seeking behaviour, this study aimed to evaluate the quality of ChatGPT-generated responses to frequently asked questions (FAQs) about HTO and to assess the reliability of two scoring systems used by orthopaedic surgeons.

Methods

Twenty-four FAQs were submitted to ChatGPT (GPT-4-turbo). Four orthopaedic surgeons independently rated the responses at two time points using: (1) a 4-point categorical scale (1 = excellent, 4 = poor), and (2) a 100-point numerical scale (0 = worst, 100 = best). Intra-observer reliability was assessed using weighted kappa (κ) and intraclass correlation coefficients (ICC); inter-observer agreement was measured using ICC values.

Results

Most responses were rated positively, with over 70% considered ‘excellent’ or requiring minimal clarification. Intra-observer agreement was variable, ranging from κ = 0.333 to 0.864 and ICC = 0.690–0.922. Inter-observer agreement was consistently low across both scales (ICC ≤ 0.390).

Conclusion

ChatGPT responses to HTO-related FAQs were rated as high quality by most evaluators. However, the low inter-observer agreement highlights the need for standardised evaluation tools and suggests that expert oversight remains essential when integrating AI-generated content into patient education.

Level of Evidence

Level V.

The posterolateral region of the knee or so-called posterolateral corner of the knee or posterolateral angle is an anatomical entity that remains relatively unknown. A clinical consensus relative to the evaluation, diagnosis and treatment of posterolateral corner injuries has recently been published. However, there are still knowledge gaps as to the precise anatomy and variability of all the structures that are part of this anatomical region. There is also paucity relative to their precise histological characteristics and their function. In addition, the nomenclature used in the literature for the posterolateral corner structures is sometimes confusing. A narrative review of the research focused on the posterolateral corner of the knee over the last hundred years was conducted. The main objective of this work was to synthesize and to bring order to the existing knowledge of the main ligamentous and tendinous components of the posterolateral corner of the knee. Twenty fresh-frozen human knees from a body donor programme were dissected to obtain anatomical images from each one of the posterolateral corner structures. Currently, there is no consensus regarding the anatomical descriptions of some of the posterolateral corner structures. Their nomenclature is still confusing, and the anatomical descriptions are not sufficiently complete. However, the images taken of each of the posterolateral corner structures show their main morphological characteristics. This work will help to develop a common framework and a consensus on the anatomy of these structures. Currently, the lack of consensus relative to the anatomy of the posterolateral region of the knee makes it difficult to resolve issues around injuries to them, their diagnosis, and the treatment of these structures.

Level of Evidence

N/A.