Purpose
Anterior cruciate ligament (ACL) graft failure is a complication that may require revision ACL reconstruction (ACL-R). Non-anatomic placement of the femoral tunnel is thought to be a frequent ...cause of graft failure; however, there is a lack of evidence to support this belief. The purpose of this study was to determine if non-anatomic femoral tunnel placement is associated with increased risk of revision ACL-R.
Methods
After screening all 315 consecutive patients who underwent primary single-bundle ACL-R by a single senior orthopedic surgeon between January 2012 and January 2017, 58 patients were found to have both strict lateral radiographs and a minimum of 24 months follow-up without revision. From a group of 456 consecutive revision ACL-R, patients were screened for strictly lateral radiographs and 59 patients were included in the revision group. Femoral tunnel placement for each patient was determined using a strict lateral radiograph taken after the primary ACL-R using the quadrant method. The center of the femoral tunnel was measured in both the posterior–anterior (PA) and proximal–distal (PD) dimensions and represented as a percentage of the total distance (normal center of anatomic footprint: PA 25% and PD 29%).
Results
In the PA dimension, the revision group had significantly more anterior femoral tunnel placement compared with the primary group (38% ± 11% vs. 28% ± 6%,
p
< 0.01). Among patients who underwent revision; those with non-traumatic chronic failure had statistically significant more anterior femoral tunnel placement than those who experienced traumatic failure (41% ± 13% vs. 35% ± 8%,
p
< 0.03). In the PD dimension, the revision group had significantly more proximal femoral tunnel placement compared with the primary group (30% ± 9% vs 38% ± 9%,
p
< 0.01).
Conclusion
In this retrospective study of 58 patients with successful primary ACL-R compared with 59 patients with failed ACL-R, anterior and proximal (high) femoral tunnels for ACL-R were shown to be independent risk factors for ACL revision surgery. As revision ACL-R is associated with patient- and economic burden, particular attention should be given to achieving an individualized, anatomic primary ACL-R. Surgeons may reduce the risk of revision ACL-R by placing the center of the femoral tunnel within the anatomic ACL footprint.
Level of evidence
Level III.
Purpose
To systematically review the literature for radiographic prevalence of osteoarthritis (OA) at a minimum of 10 years following anterior cruciate ligament (ACL) reconstruction (ACLR) with ...anatomic vs. non-anatomic techniques. It was hypothesized that the incidence of OA at long-term follow-up would be lower following anatomic compared to non-anatomic ACLR.
Methods
A systematic review was performed by searching PubMed, MEDLINE, EMBASE, and the Cochrane Library, for studies reporting OA prevalence by radiographic classification scales at a minimum of 10 years following ACLR with autograft. Studies were categorized as anatomic if they met or exceeded a score of 8 according the Anatomic ACL Reconstruction Scoring Checklist (AARSC), while those with a score less than 8 were categorized as non-anatomic/non-specified. Secondary outcomes included graft failure and measures of knee stability (KT-1000, Pivot Shift) and functional outcomes Lysholm, Tegner, subjective and objective International Knee Documentation Committee (IKDC) scores. OA prevalence on all radiographic scales was recorded and adapted to a normalized scale.
Results
Twenty-six studies were included, of which 5 achieved a score of 8 on the AARSC. Using a normalized OA classification scale, 87 of 375 patients (23.2%) had diagnosed OA at a mean follow-up of 15.3 years after anatomic ACLR and 744 of 1696 patients (43.9%) had OA at mean follow-up of 15.9 years after non-anatomic/non-specified ACLR. The AARSC scores were 9.2 ± 1.3 for anatomic ACLR and 5.1 ± 1.1 for non-anatomic/non-specified ACLR. Secondary outcomes were relatively similar between techniques but inconsistently reported.
Conclusions
This study showed that anatomic ACLR, defined as an AARSC score ≥ 8, was associated with lower OA prevalence at long-term follow-up. Additional studies reporting long-term outcomes following anatomic ACLR are needed, as high-level studies of anatomic ACLR are lacking. The AARSC is a valuable resource in performing and evaluating anatomic ACLR. Anatomic ACLR, as defined by the AARSC, may reduce the long-term risk of post-traumatic OA following ACL injury to a greater extent than non-anatomic ACLR.
Level of evidence
IV.
Purpose The purpose of this study was to objectively evaluate the anatomic and biomechanical outcomes of anterior cruciate ligament (ACL) reconstruction with transtibial versus anteromedial portal ...drilling of the femoral tunnel. Methods Ten human cadaveric knees (5 matched pairs) without ligament injury or pre-existing arthritis underwent ACL reconstruction by either a transtibial or anteromedial portal technique. A medial arthrotomy was created in all cases before reconstruction to determine the center of the native ACL tibial and femoral footprints. A 10-mm tibial tunnel directed toward the center of the tibial footprint was prepared in an identical fashion, starting at the anterior border of the medial collateral ligament in all cases. For transtibial femoral socket preparation (n = 5), a guidewire was placed as close to the center of the femoral footprint as possible. With anteromedial portal reconstruction (n = 5), the guidewire was positioned centrally in the femoral footprint and the tunnel drilled through the medial portal in hyperflexion. An identical graft was fixed and tensioned, and knee stability was assessed with the following standardized examinations: (1) anterior drawer, (2) Lachman, (3) maximal internal rotation at 30°, (4) manual pivot shift, and (5) instrumented pivot shift. Distance from the femoral guidewire to the center of the femoral footprint and dimensions of the tibial tunnel intra-articular aperture were measured for all specimens. Statistical analysis was completed with a repeated-measures analysis of variance and Tukey multiple comparisons test with P ≤ .05 defined as significant. Results The anteromedial portal ACL reconstruction controlled tibial translation significantly more than the transtibial reconstruction with anterior drawer, Lachman, and pivot-shift examinations of knee stability ( P ≤ .05). Anteromedial portal ACL reconstruction restored the Lachman and anterior drawer examinations to those of the intact condition and constrained translation with the manual and instrumented pivot-shift examinations more than the native ACL ( P ≤ .05). Despite optimal guidewire positioning, the transtibial technique resulted in a mean position 1.94 mm anterior and 3.26 mm superior to the center of the femoral footprint. The guidewire was positioned at the center of the femoral footprint through the anteromedial portal in all cases. The tibial tunnel intra-articular aperture was 38% larger in the anteroposterior dimension with the transtibial versus anteromedial portal technique (mean, 14.9 mm v 10.8 mm; P ≤ .05). Conclusions The anteromedial portal drilling technique allows for accurate positioning of the femoral socket in the center of the native footprint, resulting in secondary improvement in time-zero control of tibial translation with Lachman and pivot-shift testing compared with conventional transtibial ACL reconstruction. This technique respects the native ACL anatomy but cannot restore it with a single-bundle ACL reconstruction. Eccentric, posterolateral positioning of the guidewire in the tibial tunnel with the transtibial technique results in iatrogenic re-reaming of the tibial tunnel and significant intra-articular aperture expansion. Clinical Relevance Anteromedial portal drilling of the femoral socket may allow for improved restoration of anatomy and stability with ACL reconstruction compared with conventional transtibial drilling techniques.
Background:
Recent literature correlated anterior cruciate ligament (ACL) reconstruction failure to smaller diameter of the harvested hamstring (HS) autograft. However, this approach may be a ...simplification, as relation of graft size to native ACL size is not typically assessed and oversized grafts may impart their own complications.
Purpose:
To evaluate in vivo data to determine if the commonly used autografts reliably restore native ACL size.
Study Design:
Descriptive laboratory study.
Methods:
Intraoperative data of the tibial insertion area and HS graft diameter were collected and retrospectively evaluated for 46 patients who underwent ACL reconstruction with HS autografts. Magnetic resonance imaging measurements of the cross-sectional area (CSA) of the possible patellar tendon (PT) and quadriceps tendon (QT) autografts were also done for each patient. The percentages of tibial insertion site area restored by the 3 possible grafts were then calculated and compared for each individual.
Results:
The mean ACL tibial insertion area was 107.2 mm2 (60.5-155.5 mm2). The mean CSAs of PT, HS, and QT were 33.2, 55.3, and 71.4 mm2, respectively. When all grafts were evaluated, the percentage reconstruction of the insertion area varied from 16.2% to 123.1% on the tibial site and from 25.5% to 176.7% on the femoral site, differing significantly for each graft type (P < .05). On average, 32.8% of the tibial insertion area would have been filled with PT, 53.6% by HS, and 69.5% by QT. Based on previous cadaveric studies indicating that graft size goal should be 50.2% ± 15% of the tibial insertion area, 82.7% of patients in the HS group were within this range (36.9%, QT; 30.5%, PT), while 65.2% in the PT group were below it and 60.9% in the QT group were above it.
Conclusion:
ACL insertion size and the CSAs of 3 commonly used grafts vary greatly for each patient and are not correlated with one another. Thus, if the reconstructed ACL size is determined by the harvested autograft size alone, native ACL size may not be adequately restored. PT grafts tended to undersize the native ACL, while QT might oversize it.
Clinical Relevance:
These results may help surgeons in preoperative planning, as magnetic resonance imaging measurements can be helpful in determining individualized graft choice to adequately restore the native ACL.
The structure and function of the anterolateral complex (ALC) of the knee has created much controversy since the ‘re-discovery’ of the anterolateral ligament (ALL) and its proposed role in aiding ...control of anterolateral rotatory laxity in the anterior cruciate ligament (ACL) injured knee. A group of surgeons and researchers prominent in the field gathered to produce consensus as to the anatomy and biomechanical properties of the ALC. The evidence for and against utilisation of ALC reconstruction was also discussed, generating a number of consensus statements by following a modified Delphi process. Key points include that the ALC consists of the superficial and deep aspects of the iliotibial tract with its Kaplan fibre attachments on the distal femur, along with the ALL, a capsular structure within the anterolateral capsule. A number of structures attach to the area of the Segond fracture including the capsule-osseous layer of the iliotibial band, the ALL and the anterior arm of the short head of biceps, and hence it is not clear which is responsible for this lesion. The ALC functions to provide anterolateral rotatory stability as a secondary stabiliser to the ACL. Whilst biomechanical studies have shown that these structures play an important role in controlling stability at the time of ACL reconstruction, the optimal surgical procedure has not yet been defined clinically. Concern remains that these procedures may cause constraint of motion, yet no clinical studies have demonstrated an increased risk of osteoarthritis development. Furthermore, clinical evidence is currently lacking to support clear indications for lateral extra-articular procedures as an augmentation to ACL reconstruction. The resulting statements and scientific rationale aim to inform readers on the most current thinking and identify areas of needed basic science and clinical research to help improve patient outcomes following ACL injury and subsequent reconstruction.
Level of evidence
V.
Purpose
To compare clinical outcomes, radiographic characteristics, and surgical factors between patients with single and multiple anterior cruciate ligament (ACL) graft failures. It was hypothesized ...that patients experiencing multiple ACL graft failures exhibit lower patient-reported outcome scores (PROs) and a higher (steeper) posterior tibial slope (PTS) than patients with single ACL graft failure.
Methods
Patients undergoing revision ACL reconstruction with a minimum follow-up of 12 months were included in this retrospective cohort study. Based on the number of ACL graft failures, patients were assigned either to the group “single ACL graft failure “or” multiple ACL graft failures “. The PTS was measured on strict lateral radiographs. Validated PROs including the International Knee Documentation Committee (IKDC) subjective knee form, Knee Injury and Osteoarthritis Outcome Score, Lysholm Score, Tegner Activity Scale, ACL-Return to Sport after Injury Scale, and Visual Analogue Scale for pain were collected.
Results
Overall, 102 patients were included with 58 patients assigned to the single ACL graft failure group and 44 patients to the multiple ACL graft failures group. Quadriceps tendon autograft was used significantly more often (55% vs. 11%,
p
< 0.001) and allografts were used significantly less often (31% vs. 66%,
p
< 0.001) as the graft for first revision ACL reconstruction in patients with single versus multiple ACL graft failures. Patients with multiple ACL graft failures were associated with statistically significantly worse PROs (IKDC: 61.7 ± 19.3 vs. 77.4 ± 16.8,
p
< 0.05; Tegner Activity Scale: 4 (range, 0–7) vs. 6 (range 2–10),
p
< 0.05), higher PTS (12 ± 3° vs. 9 ± 3°,
p
< 0.001), and higher rates of subsequent surgery (73% vs. 14%,
p
< 0.001) and complications (45% vs. 17%,
p
< 0.05) than patients with single ACL graft failure.
Conclusion
Compared to single ACL graft failure in this study multiple ACL graft failures were associated with worse PROs, higher PTS, and allograft use. During the first revision ACL reconstruction, it is recommended to avoid the use of allografts and to consider slope-reducing osteotomies to avoid multiple ACL graft failures and improve PROs.
Level of evidence
Level 3.
Purpose The purpose of this systematic review was to evaluate the anatomic structure and function of the anterolateral ligament (ALL) of the knee. Methods The Medline, Embase, and Cochrane databases ...were screened for all studies related to the ALL of the knee. Two reviewers independently reviewed all eligible articles and the references of these articles. Inclusion and exclusion criteria were applied to all searched studies. Quality assessment was completed for the included studies. Results Nineteen studies were identified for final analysis. Pooled analysis identified the ALL in 430 of 449 knees (96%) examined. The ligament was found to originate from the region of the lateral femoral epicondyle and insert on the proximal tibia midway between the Gerdy tubercle and the fibular head. The ALL was found to be 34.1 to 41.5 mm in length, 5.1 to 8.3 mm in width above the lateral meniscus, and 8.9 to 11.2 mm in width below the lateral meniscus. By use of magnetic resonance imaging, the ALL was identified in 93% of knees examined (clinical, 64 of 70; cadaveric, 16 of 16). In one case study the ligament was clearly visualized by ultrasound examination. Histologic analysis across 3 studies showed characteristics consistent with ligamentous tissue. Though not shown in biomechanical studies, it is hypothesized that the ALL provides anterolateral stability to the knee, preventing anterolateral subluxation of the proximal tibia on the femur. One study identified a network of peripheral nerves, suggesting a proprioceptive function of the ALL. Conclusions This systematic review shows the ALL to be a distinct structure with a consistent origin and insertion sites. The ALL is an extra-articular structure with a clear course from the lateral femoral epicondyle region, running anteroinferiorly, to the proximal tibia at a site midway between the Gerdy tubercle and the head of the fibula. The function of this ligament is theorized to provide anterolateral knee stability. Level of Evidence Level IV, systematic review of cadaveric and imaging studies.