A new technique in double-bundle anterior cruciate ligament reconstruction using implant-free femoral fixation

Press-fit fixation in anterior cruciate ligament reconstruction yields low graft failure and revision rates: a systematic review and meta-analysis

PURPOSE

Press-fit fixation is a hardware-free technique in anterior cruciate ligament reconstruction (ACLR). The purpose of this review was to quantitatively assess the risk profile and outcomes of press-fit fixation and provide an update on its effectiveness compared to more standard fixation techniques of ACLR.

METHODS

The electronic databases PUBMED, MEDLINE, and EMBASE were searched on March 26, 2020 for therapeutic randomized controlled trials (RCT) addressing press-fit fixation for primary ACLR. The Grading of Recommendations Assessment, Development and Evaluation tool was used to assess the quality for randomized studies. A meta-analysis with a random-effects model was used to pool applicable outcomes data.

RESULTS

A total of six eligible RCTs were included in this review. There were 292 patients (72.9% male) with a mean age of 28.8 ± 3.8 years and a mean follow-up of 81.3 ± 88.3 months that underwent press-fit ACLR on the femoral, tibial or both tunnels. Femoral fixation techniques included press-fit fixation (96.6%) and cross-pin fixation (3.4%). Tibial fixation techniques included press-fit (37.0%), staples (28.1%), interference screws (21.2%) and abarticular post-screws (13.7%). Graft options included bone-patellar tend--bone autografts (73.6%) and semitendinosus and gracilis tendon autograft (26.4%). Significant improvements (p < 0.05) from baseline to follow-up were found for clinical outcomes. Significantly less postoperative bone tunnel enlargement (p < 0.05) was found with tibial press-fit fixation when compared to biodegradable screws. The overall complication rate was 13.3%. There were no significant differences in complication rates [odds ratio = 0.84 (95%CI 0.43-1.66); p = n.s.] (I² = 0%) between patients undergoing femoral press-fit fixation and femoral metal interference screw fixation.

CONCLUSION

The overall graft failure and revision rates with press-fit ACLR were low. There were no significant differences in complication rates between patients undergoing femoral press-fit and femoral metal interference screw fixation. Included studies found that patients undergoing press-fit fixation for ACLR had significant improvements in functional outcome scores postoperatively and had significantly reduced postoperative bone tunnel enlargement compared to patients undergoing bioabsorbable fixation. Thus, early evidence suggests that press-fit fixation appears to be a good option for patients undergoing ACLR.

LEVEL OF EVIDENCE

I.

Implant-free ACL reconstruction: a review

Implant-free anterior cruciate ligament (ACL) reconstruction is the fixation of ACL grafts without the need for artificial implants. Our aim was to study the evolution of this technique, review the biomechanical evidence and summarise the results. Implant-free graft fixation for bone patella tendon ACL reconstruction was first described in 1987. This concept of implant-free graft fixation was adapted for hamstring and quadriceps tendons as alternative graft sources. Various biomechanical studies have reported that by adhering to certain technical details, this technique provides comparable fixation strength as conventional ACL fixation. The outcome studies of implant-free ACL reconstruction also report clinical results similar to ACL reconstruction with conventional implants.

Comparative study between mono-bundle bone-patellar tendon-bone, double-bundle hamstring and mono-bundle bone-patellar tendon-bone combined with a modified Lemaire extra-articular procedure in anterior cruciate ligament reconstruction

PURPOSE

The aim of the study was to compare three different procedures performed by the same surgeon: mono-bundle patellar tendon reconstruction (bone-patellar tendon-bone, BPTB), double-bundle hamstring reconstruction (DBH) and mono-bundle patellar tendon combined with extra-articular reconstruction (Lemaire) (BPTB + L).

METHODS

A total of 75 patients (25 in each group) were evaluated at a mean follow-up of 25 months. Laxity was assessed pre- and post-operatively with Telos™ stress radiographs (15 kg). The amount of anterior tibial translation (ATT) corrected by the surgery was quantified. Secondary outcomes were International Knee Documentation Committee (IKDC) scores, pivot shift grading, pain complaints, sensory deficits, subsequent surgical procedures, return to sports and patients' ability to kneel or squat on their affected knee.

RESULTS

Absolute correction of ATT for the internal compartment was not statistically significant [analysis of variance (ANOVA), p=0.377]. For the external compartment BPTB + L (8.2 mm) showed superiority over DBH (5.6 mm) and BPTB (4.1 mm) (ANOVA, p=0.0001, Tukey's test). Kneeling was better in the DBH group (ANOVA, p=0.0001, Tukey's test). In 22 patients it felt normal, while only in seven in the BPTB and eight in the BPTB + L groups. Sensory deficits were present in 11 patients from the DBH group, while in 17 in the BPTB and 19 in the BPTB + L groups (ANOVA, p=0.052). Mean IKDC values, presence of anterior knee pain, subsequent operations, ability to squat and return to sports were not statistically different between groups.

CONCLUSIONS

Absolute correction of ATT was not statistically different for the medial compartment, but the patellar tendon reconstruction combined with the extra-articular procedure achieved the best lateral compartment ATT correction. Sensory deficits and kneeling seem to be worse in the groups where the patellar tendon is harvested.

Improved outcomes after anterior cruciate ligament reconstruction with quadrupled hamstring autografts and additional bone plug augmentation at five year follow-up

PURPOSE

Hybrid fixation has been proposed to improve outcomes of anterior cruciate ligament (ACL) reconstructions. This study evaluated midterm outcomes after transfemoral graft fixation using either a conventional or a modified technique using additional bone plug augmentation (BPA) of the femoral tunnel aperture.

METHODS

Seventy-one consecutive patients undergoing ACL reconstruction using a quadrupled hamstring autograft with transfemoral graft fixation and tibial interference screw fixation were included. Of these, 56 patients could be followed up 61 months (range 52-69 months) after ACL reconstruction both clinically and by magnetic resonance imaging (group A, conventional technique, n = 34; group B, modified technique, n = 22). Anteroposterior (AP) laxity measurements and International Knee Documentation Committee (IKDC), Lysholm and Tegner activity scoring were performed, while imaging included assessment of bone tunnel diameters, graft condition and graft filling at the femoral bone tunnel aperture.

RESULTS

Patients with additional BPA had a significantly higher degree of graft filling at the femoral bone tunnel aperture (p = .0135) and 'healthier' grafts (p = .0495). They also tended to display less AP laxity difference in terms of mean differences and total patient numbers. Lysholm, IKDC and Tegner activity index scores and bone tunnel diameters were not significantly different.

CONCLUSIONS

Additional BPA is an easy-to-perform, cheap and safe manoeuvre, which has the capacity to improve morphological and clinical outcomes at five year follow-up. However, femoral tunnel widening is unaffected by additional BPA.