Independent Versus Transtibial Drilling in Anterior Cruciate Ligament Reconstruction: A Meta-analysis With Meta-regression

Transtibial versus anteromedial transportal femoral tunnel in single-bundle anterior cruciate ligament reconstruction: a systematic review and meta-analysis of prospective randomized controlled trials

The purpose of this study was to systematically review and meta-analyze randomized controlled trials (RCTs) reporting the comparative clinical and functional outcomes, postoperative complications, and radiological outcomes of single-bundle anterior cruciate ligament reconstruction (ACLR) performed using the transtibial (TT) approach or anteromedial (AM) technique. A systematic review of the literature was performed according to Cochrane and PRISMA guidelines. RCTs comparing TT and AM techniques were considered only. The quality of the studies was defined using the GRADE system, and the risk of bias was assessed with the RoB 2 tool. The primary endpoint was to systematically review and meta-analyze the clinical outcomes, residual laxity and failure rate of both AM and TT techniques. In the current meta-analysis 13 RCTs involving 989 patients who underwent arthroscopic single-bundle ACLR (486 TT and 503 AM) were included. Patients undergoing AM technique resulted in higher objective-IKDC (p < 0.001) and Lysholm scores (p = 0.002), despite a lower incidence of pathological anterior tibial translation (p < 0.001) and positive pivot-shift test (p < 0.001). No differences were detected in IKDC subjective score (p = 0.26), Tegner activity scale (p = 0.18) and graft failure (p = 0.07). ACL reconstruction through AM portal technique provides better clinical outcomes and lower incidence of residual rotational and anteroposterior laxity in comparison with the TT technique. No statistically significant difference in subjective outcomes and graft failure was reported.

Meta-analysis prediction intervals are under reported in sport and exercise medicine

AIM

Prediction intervals are a useful measure of uncertainty for meta-analyses that capture the likely effect size of a new (similar) study based on the included studies. In comparison, confidence intervals reflect the uncertainty around the point estimate but provide an incomplete summary of the underlying heterogeneity in the meta-analysis. This study aimed to estimate (i) the proportion of meta-analysis studies that report a prediction interval in sports medicine; and (ii) the proportion of studies with a discrepancy between the reported confidence interval and a calculated prediction interval.

METHODS

We screened, at random, 1500 meta-analysis studies published between 2012 and 2022 in highly ranked sports medicine and medical journals. Articles that used a random effect meta-analysis model were included in the study. We randomly selected one meta-analysis from each article to extract data from, which included the number of estimates, the pooled effect, and the confidence and prediction interval.

RESULTS

Of the 1500 articles screened, 866 (514 from sports medicine) used a random effect model. The probability of a prediction interval being reported in sports medicine was 1.7% (95% CI = 0.9%, 3.3%). In medicine the probability was 3.9% (95% CI = 2.4%, 6.6%). A prediction interval was able to be calculated for 220 sports medicine studies. For 60% of these studies, there was a discrepancy in study findings between the reported confidence interval and the calculated prediction interval. Prediction intervals were 3.4 times wider than confidence intervals.

CONCLUSION

Very few meta-analyses report prediction intervals and hence are prone to missing the impact of between-study heterogeneity on the overall conclusions. The widespread misinterpretation of random effect meta-analyses could mean that potentially harmful treatments, or those lacking a sufficient evidence base, are being used in practice. Authors, reviewers, and editors should be aware of the importance of prediction intervals.

Modification of Outside-In Technique In Preparing Femoral Tunnel During Anterior Cruciate Ligament Reconstruction-"PL-Portal Outside-In Technique"

We propose modifying the outside-in technique by adopting a posterolateral (PL) portal as the working portal to introduce the anterior cruciate ligament reconstruction (ACLR) aiming guide while keeping the anteromedial portal as the viewing portal, the "PL-portal outside-in technique." This modification facilitates the preparation of an anatomical femoral tunnel, even when preserving a "big" ACL remnant or in small joint scenarios, such as pediatric ACLR. There is a minimal learning curve in adopting this technique because a standard 30° arthroscope is used, and the viewing portal is anterior.

ACL surgical trends evolve in the last five years for young European surgeons: results of the survey among the U45 ESSKA members

PURPOSE

Although the outcomes of ACL reconstruction are generally satisfying, there are several patients who do not regain their pre-injury sporting level and suffer persistent symptoms. Orthopaedic practice has evolved significantly over the last five years to address these drawbacks. The aim of the present survey was to analyze the changes in the approach to ACL reconstruction among a population of young ESSKA surgeons dedicated to ACL surgery.

METHODS

The survey was uploaded on the ESSKA website and was accessible to members under the age of 45. The ESSKA society has 1035 U45 members involved in multiple aspects of Orthopaedic practice. One hundred and forty questionnaires were returned. Several aspects of ACL surgery were investigated at baseline and 5 years prior. They included general details such as the volume of ACL reconstructions per surgeon per year, the graft choice in cases of low and high demanding patients, the technique for femoral tunnel drilling and the preferred device for femoral fixation. The approach to the management of damage to peripheral structures, as well as meniscal ramp and root tears were also investigated.

RESULTS

Hamstrings and quadrupled semitendinosus were the preferred graft choice in low-demanding patients (92.9%) while quadriceps tendon is gaining popularity in contact sport practitioners (from 4.3 to 10.7%). The percentage of surgeons using femoral screws had decreased from 37.9 to 29.3 while the percentage of those who used buttons increased from 52.9 to 69.3%. Extra-articular procedures (antero-lateral ligament (ALL) or lateral tenodesis have become popular. The percentage of surgeons who perform an additional peripheral reconstruction rose from 28.5 to 71.5%. Of those who perform the meniscal repair more than 50% of patients rose from 14.3 to 27.9%. Similarly, the percentage of surgeons who performed a medial meniscus ramp lesion repair rose from 29.4 to 54.7%. While the percentage of those who choose to perform a transtibial pull-out repair of lateral meniscus root tears significantly rose from 17.9 to 59.3%.

CONCLUSIONS

The present survey among under 45 years old ESSKA surgeons yields some notable findings. The new evidence on the impact of injuries on peripheral structures and menisci is stimulating surgeons towards a more anatomic approach if identified at the time of ACL reconstruction. This evidence will probably influence future research and decision-making.

LEVEL OF EVIDENCE

IV.

A systematic review of transphyseal ACL reconstruction in children and adolescents: comparing the transtibial and independent femoral tunnel drilling techniques

PURPOSE

Aim of this systematic review was to analyze the outcome after transphyseal ACL reconstruction in children and adolescents regarding the femoral drilling technique.

METHODS

A systematic literature search was carried out in various databases on studies on transphyseal ACL reconstruction in children and adolescents. The literature search was limited to the last 20 years. Primary outcome criterion was the failure rate. Secondary outcome criteria were growth disturbances such as leg length discrepancies or deformities and clinical scores. The present study was registered prospectively ( www.crd.york.ac.uk/PROSPERO ; CRD42022345964).

RESULTS

A total of 22 retrospective or prospective case series (level 4 evidence) were identified that reported on transphyseal ACL reconstruction in children and adolescents. The overall failure/rupture rate after transphyseal ACL reconstruction was 11.0%. The overall ACL rupture rate of the contralateral side was 9.7%. No statistical significant difference in the failure rates between independent and transtibial drilling techniques could be detected ((p = 0.76/p = 0.28)). Furthermore no statistical significant differences in the rate of reported growth disturbances between independent and transtibial drilling techniques were shown (p = 0.15). The reported clinical scores at follow-up (mean follow-up 5.05 years) revealed good to very good results.

CONCLUSION

This systematic review demonstrates that children and adolescents have a relatively high failure rate after transpyseal ACL reconstruction without any statistically significant differences between independent or transtibial drilling techniques regarding reruptur rates or the rate of growth disturbances. The results of this systematic review warrant a comparison of both techniques for femoral tunnel drilling in a controlled randomized trial.