Bone Tunnel Widening with Autogenous Bone Plugs Versus Bioabsorbable Interference Screws for Secondary Fixation in ACL Reconstruction

Background: Previous studies have investigated the effect of tension and circumferential compression on the diameter of fresh-frozen anterior cruciate ligament (ACL) allografts, but no study has described the effect on soft tissue ACL autografts harvested for implantation in the operating room for ACL reconstruction. The purpose of this study was to elucidate how hamstring autograft diameter changes during preparation for ACL reconstruction with compression in addition to tensioning. We hypothesized that autograft diameter would decrease as the graft was prepared with both tension and circumferential compression. Operative complications related to graft compression were also investigated. Methods: 100 ACL reconstruction surgeries (Age M = 15.3 ± 2.2 years; 53% male) were identified among two orthopedic surgeons. Hamstring tendon grafts were prepared in a standardized procedure to produce a looped graft for all-inside ACL reconstruction. Autografts were tensioned to 15-20 lbs and then their tibial and femoral diameters were measured using cylindrical sizing blocks. The graft diameters were measured again after placement under a saline soaked gauze for 10 minutes with the sizing blocks in place. A Wilcoxon signed rank test with correction for continuity was performed to detect significant change in autograft diameters after compression. Results: Treatment of hamstring autografts with longitudinal tension and circumferential compression significantly decreased the median tibial and femoral graft diameters by 0.75 mm. The median tibial diameter decreased from 9.50 mm to 8.75 mm (p < 0.0001) and the median femoral diameter decreased from 9.50 mm to 8.50 mm (p < 0.0001). 72% of all autografts had the same tibial and femoral diameters at implant. No intraoperative complications were noted with implantation of compressed grafts in smaller diameter tunnels. Conclusions: Median diameters of ACL hamstring autografts harvested in the OR decreased by 0.75 mm after treatment with circumferential compression using cylindrical sizing blocks. This decreased the socket size by one to two 0.5 mm sizes with no adverse events noted intra-operatively due to the compression of the grafts or the smaller sockets. Clinical Relevance: Graft integration in a bone tunnel is dependent on optimal fit of the graft inside the tunnel. If the tunnel is too small, the graft will not fit and if it is too large, it may allow joint fluid into the tunnel leading to tunnel widening and incomplete integration. Pre-tensioning a graft has been noted for many years to be an important way to properly establish the length-tension relationship of a graft. Here, we show that circumferential compression of the graft prior to implantation significantly changes the size of the graft, and thus the size of the tunnels required for implantation. In addition to providing better graft tunnel match, using smaller tunnels requires less bone removal which is particularly advantageous for pediatric, revision, and double bundle ACL reconstruction techniques where space for tunnel drilling is limited.

Download Full-text

Computed Tomography Imaging of BioComposite Interference Screw After ACL Reconstruction With Bone–Patellar Tendon–Bone Graft

Orthopaedic Journal of Sports Medicine ◽

10.1177/23259671211006477 ◽

2021 ◽

Vol 9 (5) ◽

pp. 232596712110064

Author(s):

Brian Scrivens ◽

Melissa A. Kluczynski ◽

Marc S. Fineberg ◽

Leslie J. Bisson

Keyword(s):

Computed Tomography ◽

Acl Reconstruction ◽

Femoral Tunnel ◽

Tibial Tunnel ◽

Cyst Formation ◽

Tunnel Widening ◽

Cross Sectional ◽

Interference Screws ◽

Computed Tomography Scans ◽

Tunnel Size

Background: Bioabsorbable interference screws tend to have high resorption rates after anterior cruciate ligament (ACL) reconstruction; however, no studies have examined screws composed of 30% biphasic calcium phosphate and 70% poly-d-lactide (30% BCP/70% PLDLA). Purpose: To evaluate femoral and tibial tunnel widening and resorption of 30% BCP/70% PLDLA interference screws and replacement with bone at 2 to 5 years after ACL reconstruction using bone–patellar tendon–bone (BTB) autograft. Study Design: Case series; Level of evidence, 4. Methods: Included were 20 patients who had undergone ACL reconstruction using BTB autograft and were reevaluated 2 to 5 years after surgery using computed tomography scans. Tunnel measurements were obtained from computed tomography scans in the sagittal and coronal planes and were compared with known tunnel measurements based on operative reports. These images and measurements were used to assess tunnel widening, resorption of the 30% BCP/70% PLDLA screw, its replacement with bone, and possible cyst formation. Paired t tests were used to compare initial and final femoral and tibial tunnel measurements. Results: The cross-sectional area of the femoral tunnel decreased at the aperture ( P = .03), middle ( P = .0002), and exit ( P < .0001) of the tunnel compared with the initial femoral tunnel size, and the tibial tunnel cross-sectional area decreased at the aperture ( P < .0001) and exit ( P = .01) of the tunnel compared with the initial tibial tunnel size. Bone formation was observed in 100% of femoral tunnels and 94.7% of tibial tunnels. Screw resorption was 100% in the femur and 94.7% in the tibia at the final follow-up. Cysts were noted around the femoral tunnel in 2 patients (5.1%). Conclusion: The 30% BCP/70% PLDLA interference screws used for ACL reconstruction using BTB autograft had high rates of resorption and replacement with bone, and there were no increases in tunnel size at 2 to 5 years postoperatively. The authors observed a low rate of cyst formation and no other adverse events stemming from the use of this specific biointerference screw, suggesting that this type of screw is a reasonable option for graft fixation with minimal unfavorable events and a reliable resorption profile.

Download Full-text

Bone tunnel impaction reduced the tibial tunnel enlargement

Open Medicine ◽

10.1515/med-2017-0016 ◽

2017 ◽

Vol 12 (1) ◽

pp. 99-106 ◽

Cited By ~ 2

Author(s):

Huan Xu ◽

Rongzong Zheng ◽

Jinhe Ying

Keyword(s):

Acl Reconstruction ◽

Tibial Tunnel ◽

Hamstring Tendon ◽

Bone Tunnel ◽

Tunnel Widening ◽

Tunnel Enlargement ◽

Fixation Devices ◽

Suspensory Fixation ◽

Group A ◽

The Mean

AbstractThe purpose of this study was to investigate whether the bone tunnel impaction technique performed by dilators could dwindle the tibial tunnel enlargement after anterior cruciate ligament (ACL) reconstruction with hamstring tendon using both extracortical suspensory fixation devices at femoral and tibial site.Thirty-one consecutive patients undergoing primary ACL reconstruction with the hamstring autograft were enrolled in this research. Patients were randomly allotted to group A (bone tunnel impaction technique using dilators) or group B (regular extraction bone tunnel drilling).ResultsThe average follow-up was 16.2 months. The mean femoral tunnel widening was 1.05 mm and 1.02 mm respectively in group A and B. The mean tibial tunnel widening was 0.61 mm and 1.08 mm respectively in group A and B. There was no statistical difference for tunnel enlargement between the two groups at the femoral site (P = 0.62) but significant difference at the tibial site (P < 0.0001).ConclusionBone tunnel impaction technique leaded to a reduction of tibial bone tunnel enlargement after ACL reconstruction with hamstring tendon using both extracortical suspensory fixation devices at femoral and tibial site.

Download Full-text

BONE TUNNEL ENLARGEMENT WITH NON-METALLIC INTERFERENCE SCREWS IN ACL RECONSTRUCTION

Acta Ortopédica Brasileira ◽

10.1590/1413-785220182605199995 ◽

2018 ◽

Vol 26 (5) ◽

pp. 305-308 ◽

Cited By ~ 1

Author(s):

Vitor Barion Castro de Padua ◽

Júlio Cesar Rodrigues Vilela ◽

Wendel Aculha Espindola ◽

Rafael Cassiolato Garcia Godoy

Keyword(s):

Acl Reconstruction ◽

Femoral Tunnel ◽

Tibial Tunnel ◽

Bone Tunnel ◽

Tunnel Enlargement ◽

Interference Screws ◽

Bone Tunnel Enlargement ◽

Reconstruction Methods ◽

Significant Difference ◽

Bone Tunnels

ABSTRACT Objective: To compare the widening of bone tunnels between poly-etheretherketone (PEEK), absorbable polylactic acid DL (PLDL) and tricalcium phosphate (TCP) interference screws in anterior cruciate ligament (ACL) reconstruction. Methods: Three groups of patients undergoing ACL reconstruction with at least 1 year of follow-up using the out-in drilling technique and hamstring as a graft were assessed. The patients were divided according to the type of interference screw used (PEEK, PLDL and TCP). Computed tomography (CT) was performed to measure the greatest femoral and tibial tunnel widening regarding to the initial tunnel, and then it was compared between groups. Results: Mean widening in group 1 (PEEK) was 39.56% (SD 16%) in the femoral tunnel and 33.65% (SD 20%) in the tibia. In group 2 (PLDL) mean widening was 48.43% in the femoral tunnel (SD 18%) and 35.24% (SD 13%) in the tibial tunnel. In group 3 (TCP) mean widening was 44.51% in the femur (SD 14%) and 36.83% in the tibia (SD 14%). The comparison between groups (PLDL-PEEK, PLDL-TCP, PEEK-TCP) shows no statistically significant difference. Conclusion: Bone tunnel enlargement values after ACL reconstruction with the use of different types of materials (bioinert and biomaterials) of interference screws (PEEK, PLDL and TCP) were similar. Level of Evidence III, Comparative retrospective study.

Download Full-text

PEDIATRIC ACL RECONSTRUCTION: DOES THE FEMORAL PEEK IMPLANT CAUSE TUNNEL WIDENING?

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967119s00189 ◽

2019 ◽

Vol 7 (3_suppl) ◽

pp. 2325967119S0018

Author(s):

Lydia Saad ◽

Guy Grimard ◽

Marie-Lyne Nault

Keyword(s):

Acl Reconstruction ◽

Femoral Tunnel ◽

Cruciate Ligament ◽

Chemical Properties ◽

Bone Tunnel ◽

Reference Points ◽

University Hospital ◽

Tunnel Widening ◽

Tunnel Enlargement

Background: Because of their strength, inertness and biocompatibility, polyetherketone (PEEK) implants have been increasingly used in orthopedics, especially trauma and spine surgeries. Their mechanical and chemical properties have been widely studied and compared to other materials since their accelerated development in the 1980s. Their use is relatively new in anterior cruciate ligament reconstructions (ACLR), and there is little literature to document their effect on tunnel widening in these procedures. Bone tunnel enlargement following ACLR is a widely reported phenomenon that has been negatively correlated with clinical outcome scores. A recent prospective study reiterated its stronger association with suture discs compared with methods using interference screws, cross-pins and buttons. There is only one paper that specifically reports the results of a study on PEEK implants in relation with tunnel widening and it did not demonstrate significant association. PEEK polymer has not yet been studied in pediatric knees, in which tunnel widening has more than the usual residual laxity and re-tear implications, as it can also cause physeal damage. The purpose of this study was to investigate the use of a femoral PEEK implant in ACLR performed on skeletally immature patients and to determine if it is associated with tunnel widening. As a secondary objective, this study aimed to assess the risk of growth complications associated with the use of PEEK. Methods: All patients who underwent all-epiphyseal ACLR surgery in a pediatric university hospital between March 2015 and January 2017 were included in this retrospective study. The all-epiphyseal ACL reconstruction procedures were done using a new instrumentation system that includes a titanium tibial anchor fixation and a femoral PEEK screw system. Femoral bone tunnel diameters were measured on postoperative lateral knee radiographs. The widest tunnel measurements were taken using the sclerotic tunnel margins as reference points and compared to the known sizes of the drill bits retrieved from operative protocols. Paired t tests were performed to assess bone tunnel widening. P-values <0.05 were considered significant. SPSS 25.0 was used for statistical analysis. Results: Eighteen (19 knees) arthroscopic ACL reconstruction patients were included. Of the 18 all-epiphyseal ACL reconstruction patients, 4 (22.2%) were female and 14 (77.8%) were male. The chronological and bone ages at time of surgery (mean ± SD) were respectively 13.5 ± 1.6 and 13.3 ± 1.0 years. At a mean follow-up of 17.1 months, average tunnel enlargement was 1.8± 1.4 (0.0-4.2) mm at the femur and was found to be statistically significant (P<0.001). There were no symptomatic growth abnormalities requiring intervention, but 2 unilateral early physeal closures at the distal femur (10.5%) were noted. These patients had notable femoral tunnel enlargement. One had a 3.0 mm of femoral tunnel widening and no observable growth disturbance. The other had an asymptomatic and non-progressive unilateral knee valgum of 5 degrees and 3.5 mm of femoral tunnel widening. Conclusions/significance: This study showed that the largest tunnel increase at a mean follow up of 17.1 months was 4.2 mm. It is not clear that this widening is clinically significant even though it is statistically significant. Also, association between femoral tunnel widening and physeal closure could not be formally established. Thus, further research on this potential risk factor is needed.

Download Full-text

Can the body slope of interference screw affect initial stability of reconstructed anterior cruciate ligament?: An in-vitro investigation

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04446-8 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Nazanin Daneshvarhashjin ◽

Mahmoud Chizari ◽

Javad Mortazavi ◽

Gholamreza Rouhi

Keyword(s):

Anterior Cruciate Ligament ◽

Acl Reconstruction ◽

Cruciate Ligament ◽

Bone Tunnel ◽

Reconstruction Process ◽

Interference Screws ◽

Bone Screw ◽

Initial Stability ◽

Tunnel Diameter ◽

Anterior Cruciate

Abstract Background Superior biomechanical performance of tapered interference screws, compared with non-tapered screws, with reference to the anterior cruciate ligament (ACL) reconstruction process, has been reported in the literature. However, the effect of tapered interference screw’s body slope on the initial stability of ACL is poorly understood. Thus, the main goal of this study was to investigate the effect of the interference screw’s body slope on the initial stability of the reconstructed ACL. Methods Based on the best screw-bone tunnel diameter ratios in non-tapered screws, two different tapered interference screws were designed and fabricated. The diameters of both screws were equal to bone tunnel diameter in one-third of their length from screw tip, then they were gradually increased by 1mm, in the lower slope (LSTIS), and 2 mm, in the higher slope (HSTIS) screws. To simulate the ACL reconstruction, sixteen soft tissue grafts were fixed, using HSTIS and LSTIS, in synthetic bone blocks. Through applying sub-failure cyclic incremental tensile load, graft-bone-screw construct’s stiffness and graft laxity in each cycle, also through applying subsequent step of loading graft to the failure, maximum load to failure, and graft’s mode of failure were determined. Accordingly, the performance of the fabricated interference screws was compared with each other. Results HSTIS provides a greater graft-bone-screw construct stiffness, and a lower graft laxity, compared to LSTIS. Moreover, transverse rupture of graft fibers for LSTIS, and necking of graft in the HSTIS group were the major types of grafts’ failure. Conclusions HSTIS better replicates the intact ACL’s behavior, compared to LSTIS, by causing less damage in graft’s fibers; reducing graft laxity; and increasing fixation stability. Nonetheless, finding the optimal slope remains as an unknown and can be the subject of future studies.

Download Full-text