Academy of Orthopaedic Surgeons Clinical Practice Guideline Summary: Management of Anterior Cruciate Ligament Injuries

Gradual stabilization and narrowing of bone tunnels following primary anterior cruciate ligament reconstruction

PURPOSE

The purpose of this study is to dynamically assess variations in tunnel diameters following anterior cruciate ligament reconstruction (ACLR) and investigate correlations with patient-reported outcomes (PROs) and graft maturity based on signal-to-noise quotient (SNQ).

METHODS

Tunnel diameter and tunnel position were measured using three-dimensional models derived from computed tomography (CT) data. Postoperative graft maturity and integration were evaluated using magnetic resonance imaging (MRI). Clinical outcomes were assessed through PROs, which included the International Knee Documentation Committee Subjective Knee Evaluation Form, Knee Injury and Osteoarthritis Outcome Scores and Lysholm scores. The correlation between tunnel enlargement extent, PROs and SNQ values, as well as correlations between confounding factors, tunnel diameter differences and SNQ were analyzed.

RESULTS

A total of 73 participants underwent primary ACLR and scheduled follow-ups. At the segment of the articular aperture, the femoral tunnel was enlarged by 32.3% to 10.4 ± 1.6 mm (p < 0.05), and the tibial tunnel was widened by 17.2% to 9.6 ± 1.2 mm (p < 0.05) at the 6-month follow-up. At 1 year postoperatively, diameters at the articular aperture were not further increased on the femoral (n.s.) and tibial (n.s.) sides. In early postoperative follow-up, the femoral tunnel was anteriorly and distally shifted, coupled with posterior and lateral deviation involving the tibial side, exhibiting minimal migration at 1-year follow-up. The degree of tunnel widening was not correlated with PROs and SNQ values. Age, gender, body mass index (BMI), time from surgery to follow-up, concomitant injuries and autograft type were not correlated with tunnel diameter differences and SNQ.

CONCLUSIONS

The femoral and tibial bone tunnels exhibited eccentrical widening and gradually stabilized at 1 year following ACLR. Furthermore, the enlarged bone tunnels were not correlated with unsatisfied PROs and inferior graft maturity.

LEVEL OF EVIDENCE

Level IV.

Investigation of the anatomic risk factors in acute anterior cruciate ligament ruptures to develop ramp lesions of the medial meniscus by quantitative MRI

OBJECTIVE

To investigate the anatomic risk factors of knee in patients with acute non-contact anterior cruciate ligament (aACL) ruptures to develop ramp lesions.

METHODS

A total of 202 subjects were retrospectively divided into three groups: (1) aACL ruptures combined with ramp lesions group (n = 76); (2) isolated ACL ruptures group (n = 56) and (3) normal controls group (n = 70). Quantitative morphological parameters on MRI were measured including: diameter of medial femoral condyle (MFC), anterior-posterior length and depth of medial tibial plateau (MTP AP length and depth), lateral posterior tibial slope (LPTS) and medial posterior tibial slope (MTPS), asymmetry of LPTS and MPTS (LMPTS), lateral meniscal slope (LMS), and medial meniscal slope (MMS).

RESULTS

The MTP AP length, MTP AP length/MFC diameter ratio, MTP depth, LPTS and the asymmetry of LMPTS showed significant differences among the three groups (p < 0.001). The risk factors associated with the ramp lesions including a longer MTP AP length (OR 1.17, 95% CI 1.00-1.44, p = 0.044), increased MTP depth (OR 1.91, 95% CI 1.22-3.00, p = 0.005) and lager ratio (OR 1.11, 95% CI 1.01-1.22, p = 0.036). The highest AUC was the MTP AP length/MFC diameter ratio (0.74; 95% CI, 0.66-0.82). The combination model increased higher accuracy (0.80; 95% CI, 0.72-0.88).

CONCLUSION

Several bony anatomic characteristics of the knee, especially the morphology of medial tibia plateau, are additional risk factors for aACL ruptures to develop ramp lesions.

CRITICAL RELEVANCE STATEMENT

Predictive anatomic risk factors of the knee for patients with acute non-contact anterior cruciate ligament (aACL) ruptures to develop ramp lesions, especially the morphology of medial tibia plateau, are detectable by MRI.

KEY POINTS

Ramp lesion development can complicate aACL ruptures and requires specific treatment. Longer AP length and increased MTP depth are risk factors for concurrent ramp lesions. Identification of ramp lesions allows for the most appropriate treatment.

Preferences in anterior cruciate ligament reconstruction: A survey among orthopedic surgeons in China

The purpose of this study was to reveal the current trends and preferences of Chinese orthopedic surgeons regarding anterior cruciate ligament (ACL) reconstruction through a nationwide web-based survey conducted in China. The survey questionnaire was distributed via WeChat to the chairmen of provincial orthopedic and sports medicine organizing committees in China, who then shared it in their respective WeChat workgroups. The questionnaire consisted of 52 multiple-choice questions covering 8 sections. Data collection was implemented by Questionnaire Star. A total of 812 valid questionnaires were returned: 94.21% of the respondents preferred single-bundle reconstruction of ACL, while 61.70% preferred autogenous semitendinosus plus gracilis reconstruction; 76.35% of the respondents preferred establishing the femoral tunnel first, while 47.29% preferred establishing the femoral tunnel through a medial auxiliary approach; and 85.10% of the respondents recommended patients to undergo surgery within 3 months after ligament injury. Besides, the vast majority of respondents chose to retain the ligamentous remnant bundle (92.98%) and recommended routine use of knee braces postoperatively (94.09%). It is recommended to perform arthroscopic single-bundle ACL reconstruction with the remnant preserving technique using a hamstring autograft within 3 months of ACL rupture, with support of postoperative functional braces.

Delaying anterior cruciate ligament reconstruction increases the rate and severity of medial chondral injuries

Aims

The aim of this study was to evaluate the association between chondral injury and interval from anterior cruciate ligament (ACL) tear to surgical reconstruction (ACLr).

Methods

Between January 2012 and January 2022, 1,840 consecutive ACLrs were performed and included in a single-centre retrospective cohort. Exclusion criteria were partial tears, multiligament knee injuries, prior ipsilateral knee surgery, concomitant unicompartmental knee arthroplasty or high tibial osteotomy, ACL agenesis, and unknown date of tear. A total of 1,317 patients were included in the final analysis, with a median age of 29 years (interquartile range (IQR) 23 to 38). The median preoperative Tegner Activity Score (TAS) was 6 (IQR 6 to 7). Patients were categorized into four groups according to the delay to ACLr: < three months (427; 32%), three to six months (388; 29%), > six to 12 months (248; 19%), and > 12 months (254; 19%). Chondral injury was assessed during arthroscopy using the International Cartilage Regeneration and Joint Preservation Society classification, and its association with delay to ACLr was analyzed using multivariable analysis.

Results

In the medial compartment, delaying ACLr for more than 12 months was associated with an increased rate (odds ratio (OR) 1.93 (95% confidence interval (CI) 1.27 to 2.95); p = 0.002) and severity (OR 1.23 (95% CI 1.08 to 1.40); p = 0.002) of chondral injuries, compared with < three months, with no association in patients aged > 50 years old. No association was found for shorter delays, but the overall dose-effect analysis was significant for the rate (p = 0.015) and severity (p = 0.026) of medial chondral injuries. Increased TAS was associated with a significantly reduced rate (OR 0.88 (95% CI 0.78 to 0.99); p = 0.036) and severity (OR 0.96 (95% CI 0.92 to 0.99); p = 0.017) of medial chondral injuries. In the lateral compartment, no association was found between delay and chondral injuries.

Conclusion

Delay was associated with an increased rate and severity of medial chondral injuries in a dose-effect fashion, in particular for delays > 12 months. Younger patients seem to be at higher risk of chondral injury when delaying surgery. The timing of ACLr should be optimally reduced in this population.