Tunnel Widening After Anatomic Double-Bundle and Mid-Position Single-Bundle Anterior Cruciate Ligament Reconstruction

Department of Orthopaedic and Trauma Surgery, Martin Luther Hospital, Berlin, Germany. Electronic address: .
Arthroscopy The Journal of Arthroscopic and Related Surgery (Impact Factor: 3.21). 09/2013; 29(9):1514-24. DOI: 10.1016/j.arthro.2013.06.002
Source: PubMed


The purpose of this study was to compare the amount of postoperative bone tunnel enlargement after anatomic double-bundle (DB) and single-bundle (SB) anterior cruciate ligament (ACL) reconstruction 6 to 8 months after surgery.
Twenty-one consecutive patients undergoing anatomic 4-tunnel DB ACL reconstruction and 24 patients undergoing anatomic 2-tunnel SB ACL reconstruction were included in this study. In both groups a hybrid fixation technique with interference screw and extracortical fixation at the tibia and an extracortical fixation technique at the femur were used. Magnetic resonance imaging was performed on the second postoperative day and at a mean of 8 months' follow-up (range, 6.8 to 8.3 months) to assess intraoperative and postoperative bone tunnel enlargement. Tunnel widening was determined in different planes by digitally measuring the diameters of the bone tunnels. Tunnel position was measured and classified according to Harner et al. (femoral) and Stäubli et al. and Petersen et al. (tibial).
Magnetic resonance imaging showed that all bone tunnels were anatomically placed within the area of the original ACL insertion zone. Compared with the intraoperative drill diameter, we observed only a slight increase in tunnel diameter in both groups on the second postoperative day. At 8 months postoperatively, significant bone tunnel widening occurred in all bone tunnels (P < .001). However, no significant differences were found between tunnel enlargement in the DB group and tunnel enlargement in the SB group (P > .05), either on the tibial side or on the femoral side. In 2 cases tibial tunnel communication was noted at follow-up.
With the use of anatomic SB and DB ACL reconstruction techniques, the results of bone tunnel enlargement were comparable; no significant difference was observed between the tibial and femoral tunnels.
Level III, prospective comparative study.

Download full-text


Available from: Andrea Achtnich, Mar 18, 2014
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate changes in femoral tunnel diameter, dimension, and volume after anterior cruciate ligament reconstruction with notchplasty. Porcine knee specimens were divided into 2 groups of 10 specimens each. Group A did not receive notchplasty. A 2-mm notchplasty was conducted in group B. Seven-millimeter-diameter femoral tunnels were drilled and a doubled flexor digitorum profundus tendon was inserted and fixed with an EndoButton (Smith & Nephew, Andover, MA) in each knee specimen. Samples were mounted on a materials testing machine. Each group was preloaded at 10 N and subjected to 20 loading cycles (between 0 and 40 N), followed by 1,000 loading cycles in the elastic region (between 10 and 150 N). High-resolution computed tomography with 1.0-mm slices was conducted with all samples before and after testing. A 3-dimensional model was constructed to evaluate the degree of the tunnel change. In group B the mean longest diameter and dimension of the femoral tunnel significantly increased after the test (P = .005 and P = .001, respectively). The volumetric loss of bony structure after the test in group B was significantly greater than that in group A (P = .039). Meanwhile, no significant difference was found before and after the test in terms of tunnel diameter, dimension, and volumetric loss around the tunnel in group A. The intra-articular orifice of the femoral tunnel was enlarged after the uniaxial cyclic loading test after notchplasty. An enlarged tunnel orifice may lead to a discrepancy between the tunnel and the graft at the tunnel aperture. The data may have an implication that suspensory fixation with a notchplasty has a negative effect on the full graft accommodation at the tunnel aperture. Aperture widening may affect graft positioning, leading to subtle changes in graft biomechanics and laxity.
    No preview · Article · Apr 2014 · Arthroscopy The Journal of Arthroscopic and Related Surgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: Interference screw fixation is a standard procedure in anterior cruciate ligament (ACL) replacement. Aim of this study was to evaluate the degradation process of Poly-D-L-lactide (PDLLA) interference screws used for tibial ACL graft fixation. Materials and methods: We evaluated magnetic resonance imaging (MRI) scans of 18 patients who underwent ACL revision surgery at different time points after anatomic ACL reconstruction. At primary surgery, a tibial hybrid fixation was performed with a degradable interference (IF) screw made of PDLLA (Megafix(®)) and a button. Results: MRI revealed three different phases of degradation of the PDLLA screw. 6-8 months after surgery the IF screw was clearly visible as a well-defined structure on MRI and CT scan. After 12-16 months, the screws appeared less defined with central ingrowths' of connective tissue. In some cases only fragmented screw material was visible. At these time points, there was a slight edema surrounding the tunnel visible on MRI. After 22 months and later, the mean screw site densities were comparable with the surrounding bone density. There was no edema or signs of inflammation around the bone tunnels visible. Presence of cystic or osteolytic changes was not detected. Conclusion: After 22 months, a PDLLA screw may not interfere with ACL revision surgery. Regarding the degradation process of PDLLA screws, we noted three different phases. Furthermore, the degradation process observed by MRI resembles to that described by animal studies. The PDLLA screws fully absorb and are partially replaced by bone. The degradation process in humans seems to be longer than that described in animals.
    No preview · Article · Jun 2014 · Archives of Orthopaedic and Trauma Surgery
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Purpose The aim of this systematic review was to apply the anatomic ACL reconstruction scoring checklist (AARSC) and to evaluate the degree to which clinical studies comparing single-bundle (SB) and double-bundle (DB) ACL reconstructions are anatomic. Methods A systematic electronic search was performed using the databases PubMed (MEDLINE), EMBASE and Cochrane Library. Studies published from January 1995 to January 2014 comparing SB and DB ACL reconstructions with clinical outcome measurements were included. The items from the AARSC were recorded for both the SB and DB groups in each study. Results Eight-thousand nine-hundred and ninety-four studies were analysed, 77 were included. Randomized clinical trials (29; 38 %) and prospective comparative studies (29; 38 %) were the most frequent study type. Most studies were published in 2011 (19; 25 %). The most commonly reported items for both SB and DB groups were as follows: graft type (152; 99 %), femoral and tibial fixation method (149; 97 % respectively), knee flexion angle during graft tensioning (124; 81 %) and placement of the tibial tunnel at the ACL insertion site (101; 66 %). The highest level of documentation used for ACL tunnel position for both groups was often one dimensional, e.g. drawing, operative notes or o’clock reference. The DB reconstruction was in general more thoroughly reported. The means for the AARSC were 6.9 ± 2.8 for the SB group and 8.3 ± 2.8 for the DB group. Both means were below a proposed required minimum score of 10 for anatomic ACL reconstruction. Conclusions There was substantial underreporting of surgical data for both the SB and DB groups in clinical studies. This underreporting creates difficulties when analysing, comparing and pooling results of scientific studies on this subject.
    Full-text · Article · Oct 2014 · Knee Surgery Sports Traumatology Arthroscopy
Show more