Primary Anterior Cruciate Ligament Reconstruction Research Articles

Risk-factor analysis of the proximal tibia morphology for secondary ipsilateral injury after anterior cruciate ligament reconstruction: A retrospective cross-sectional study.

Many studies have reported the risk factors associated with primary anterior cruciate ligament (ACL) injury. However, few studies have focused on the bony morphology of secondary ipsilateral injury after ACL reconstruction. This study aimed to investigate the morphological risk factors of the proximal tibia contributing to secondary ipsilateral injury after ACL reconstruction. Twenty patients who were selected from secondary ipsilateral injury after ACL reconstruction between January 2015 and May 2020 were included in the secondary injury group. They were matched in a 1:2 ratio to the control group, which underwent primary ACL reconstruction during the same period and did not experience reinjury at the minimum 2-year follow-up, based on age, gender, and body mass index. All parameters, including medial tibial posterior slope, lateral tibial posterior slope (LTPS), medial tibial plateau depth, and lateral tibial plateau height, were recorded by using magnetic resonance imaging. Binary logistic regression analysis and receiver operator characteristic curves were conducted to explore the risk factors for reinjury and determine the cutoff value for the significant parameter. The LTPS was significantly larger in the secondary injury group than in the control group (9.6 ± 1.5° to 7.0 ± 1.4°, P < .001), and there was no significant difference in the medial tibial posterior slope, medial tibial posterior slope, and lateral tibial plateau height between the 2 groups (P > .05). The LTPS was found to be an independent risk factor for secondary ipsilateral injury after ACL reconstruction (odds ratio = 3.220, 95% confidence interval = 1.904-5.446, P < .001). The cutoff value of the LTPS was 8.8°, with a sensitivity of 91.7% and a specificity of 81.2%. The LTPS could be a unique predictor of secondary ipsilateral injury after ACL reconstruction. Orthopedists should implement effective measurements during primary reconstruction when the LTPS is >8.8°.

It is challenging to reproduce both anatomical and functional aspects of anterolateral reconstruction: postoperative 3D-CT analysis of the femoral tunnel position

BackgroundThis study aimed to evaluate the femoral tunnel position and fiber length of the anterolateral ligament (ALL) reconstruction compared with the natural anatomy of the ALL. We also evaluated whether the femoral tunnel position would affect residual pivot shift.MethodsThis study was a retrospective review of 55 knees that underwent ALL reconstruction considering the anatomical and functional aspects, during primary anterior cruciate ligament (ACL) reconstruction in the presence of a high-grade pivot shift or revisional ACL reconstruction. We determined the position of the femoral tunnel and the length of graft using a three-dimensional (3D)-computed tomography (CT) model after ALL reconstruction. We also measured graft excursion during surgery and examined pivot shift 2 years after surgery. We conducted a subgroup analysis of femoral tunnel position, fiber length, isometricity, and residual pivot shift depending on whether the tunnel was anterior or posterior to the lateral epicondyle (LE). We also performed a subgroup analysis depending on whether the ACL reconstruction was primary or revisional.ResultsThe mean femoral tunnel position was 2.04 mm posterior and 14.5 mm proximal from the center of the LE. The mean lengths of the anterior and posterior fibers were 66.6 and 63.4 mm, respectively. The femoral tunnel was positioned more proximally than the anatomical position, and both anterior and posterior ALL fibers were longer than the natural anatomy. The anteroposterior femoral tunnel position was significantly correlated with anterior (p = 0.045) and posterior (p = 0.037) fiber excursion. In the subgroup analysis, there was no significant difference in the residual pivot shift between the posterior and anterior tunnel positions. However, there were significant differences for proximal position (p < 0.001) and fiber length (p = 0.006). There was no significant difference between primary and revisional ACL regarding femoral tunnel position and fiber lengths.ConclusionIt is challenging to reproduce both anatomical and functional aspects of ALL reconstruction in both primary and revision ACL reconstruction. Especially for functional reconstruction, the femoral tunnel tended to be positioned more proximally than the anatomical position. However, the femoral tunnel position did not affect functional clinical outcomes at the 2-year follow-up.Level of evidenceLevel IV Case series.

Graft choice to decrease the revision rate of anterior cruciate ligament reconstruction: a nationwide retrospective cohort study

There are many graft choices for anterior cruciate ligament (ACL) reconstruction, including autografts and allografts. The choice of graft has been identified as a significant factor affecting the outcome of ACL reconstruction. This study aimed to determine whether allograft or autograft is better for avoiding revisional ACL reconstruction. The National Health Insurance Service-Health screening database analyzed 146,122 patients who underwent ACL reconstruction surgery from Jan. 1, 2002, to Dec. 31, 2021. The study was conducted in two groups, autograft or allograft, and the rates of revision ACL reconstruction between the two groups were compared. Propensity score matching and multivariable Cox Proportional Hazard model analysis were used. The significant predictors for complications (p < 0.05) were as follows. The total of patients with ACL reconstruction was 146,122. Allograft was used in 121,148 patients, and autograft was used in 24,974 patients. 9.2% of the allograft group and 8.7% of the autograft group underwent revision ACL reconstruction. (P < .0001) 70.0% & 63.6% of patients underwent revision surgery within 1 year in the allograft & autograft groups, respectively. In summary, using autograft in primary ACL reconstruction is helpful in lowering the rate of revision surgery.

After 40 days intra-articular injury, risk profile increases linearly with time to surgery in adolescent patients undergoing primary anterior cruciate ligament reconstruction.

Anterior cruciate ligament (ACL) injuries are becoming more common in youth athletes. Time-to-surgery has been shown to significantly affect the rates of concurrent injuries at the time of ACL reconstruction (ACLR). The purpose of this study was to evaluate if time-to-surgery in ACLR impacts observances of intra-articular injuries and to categorize injury profile in relation to time. An Institutional Review Board-approved retrospective cohort study was conducted. Included subjects were aged 21 and below and underwent primary ACLR within 6 months of injury between January 2012 and April 2020. Skeletal maturity was determined via imaging. Laterality, location and severity/pattern of meniscal and chondral injuries were recorded. Multivariate logistic regression was utilized to identify risk factors for intra-articular pathology. Cut-off analyses were added to regression models to identify trends of concurrent injuries. Eight hundred and fifty patients met the inclusion criteria. Patients with observed articular cartilage injuries had a significantly longer time-to-surgery of 66 days (p = 0.01). Risk factors for chondral injury were time-to-surgery (p = 0.01) and skeletal maturity (p = 0.01), while medial meniscal tears were prognosticated by time-to-surgery (p = 0.03), skeletal maturity (p = 0.01) and body mass index (p = 0.00). Cut-off analysis showed that after 40 days the proportion of patients with observed chondral injury increased with time to surgery and that there were significantly different observances of chondral (p = 0.00) and medial meniscal (p = 0.03) injuries in the 6-week model, as compared to the continuous time model. Longer time-to-surgery in ACLR is associated with higher rates of concomitant intra-articular pathology, especially chondral injuries. After 40 days, the observed rates of intra-articular injury increase proportionately with time from injury. A 6-week categorical model best stratifies intra-articular injury risk profile. Risk factor analysis identified skeletally mature patients with delayed surgery of >12 weeks to be at the highest risk for both chondral and medial meniscal injuries after an ACLR. Level III.

Failure rate of isolated medial meniscus repair in the stable knee: Systematic review and meta-analysis.

The present meta-analysis aims to determine the outcomes and failure rates for medial meniscus repairs in patients with stable knees. A literature search was conducted using PubMed and Scopus with the terms '(medial meniscus OR medial meniscal) AND (repair)'. The search strategy was based on the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) protocol and included 93 articles assessed for eligibility. The search criteria were limited to studies reporting outcomes and failure rates. The exclusion criteria included languages other than English, biomechanical studies, letters to editors, non-full text, review articles, meta-analyses and case reports. In total, 10 studies with 595 patients were included. Degenerative tears or studies reporting meniscus repair outcomes on root repairs, revision or primary anterior cruciate ligament reconstruction, discoid menisci or ramp lesions were excluded. All studies included revision surgery and/or clinical symptoms as failure definitions. The overall medial meniscal repair failure rate was 26% with a 95% confidence interval (CI) [15%-37%]. The mean time to failure from isolated medial meniscus repair surgery was 27.7 months with 95% CI [18.5-36.9 months]. The postoperative Lysholm and IKDC scores were reported in three articles. At the final follow-up, the mean postoperative Lysholm and IKDC scores were 92.3 with 95% CI [84.5-100] and 88.6 with 95% CI [83.5-93.8], respectively. The current meta-analysis revealed an overall failure rate of 26% in the case of medial meniscus repair in a stable knee. For these reasons, the patient should be aware of the substantial risk of revision surgery (one out of four cases). Medial meniscus repair in a stable knee yielded good clinical results. II.

Proximally positioned femoral grafts decrease passive anterior tibial subluxation in anterior cruciate ligament reconstruction using a posterior trans-septal portal.

To compare the anterior and posterior trans-septal (TS) portal approaches in anterior cruciate ligament reconstruction (ACLR) by evaluating femoral tunnel positioning and passive anterior tibial subluxation (PATS). A total of 205 patients who underwent primary ACLR using the outside-in technique between March 2018 and December 2021 were retrospectively enrolled. Patients were classified into two groups based on the viewing techniques: the anterior group was treated using anteromedial or anterolateral portals (n = 155), and the TS group was treated using posterior TS portal (n = 55). The relative locations of the femoral tunnel were evaluated using the deep-shallow planes (X-axis) and superior-inferior planes (Y-axis) with the quadrant method in the lateral femoral condyle on a 3-dimensional computed tomography image. Anterior tibial subluxation for the lateral and medial compartments relative to the femoral condyles was evaluated as measured on magnetic resonance imaging. Knee laxity was assessed using the pivot-shift test and stress radiography. In the posterior TS group, the femoral tunnel was usually located deeper on the X-axis and more superior on the Y-axis, which corresponds to a more proximal position, than in the anterior group (deeper on the X-axis and superior on the Y-axis). Moreover, the femoral tunnel locations in this group were more compactly distributed than those in the anterior group. The TS group showed significantly better reduction of postoperative PATS in the lateral compartments than the anterior group (anterior group vs. TS group: lateral compartment, 3.2 ± 3.1 vs. 4.5 ± 3.2mm; p = .016). Significantly better results were found in the TS group for knee stability as assessed by the pivot-shift grade (p = .044); however, there were no significant differences between the two groups with respect to patient-reported outcome measures (p > .05) and other complications (p = .090). Our results suggest that positioning the femoral tunnel using the posterior TS portal approach may lead to better outcomes in terms of PATS and rotational stability compared to the anterior portal approach in ACLR.

Increased rate of surgery for loss of motion following anterior cruciate ligament reconstruction during COVID-19

ObjectivesTo investigate the incidence and risk factors associated with loss of motion after anterior cruciate ligament reconstruction (ACLR) during the coronavirus disease 2019 pandemic (COVID-19). MethodsA retrospective review of patients undergoing primary ACLR between March 2017 and November 2022 by a senior high-volume orthopaedic surgeon was performed. Exclusion criteria included revision ACLR, multiligamentous knee surgery, and age <14 years. The COVID-19 group was categorized according to the United States Centers for Disease Control Public Health Emergency declaration dates (January 31, 2020–May 11, 2023). To minimize confounding variables associated with the early stages of COVID-19, patients who underwent ACLR between December 1, 2019 and February 29, 2020 were excluded. Loss of motion was defined using the International Knee Documentation Committee criteria for loss of motion of the knee (i.e. an extension deficit >5° or flexion deficit >15° compared to the contralateral knee) 3–12 months after ACLR or as requiring surgery to restore motion within 12 months of ACLR. ResultsA total of 336 individuals who underwent 352 primary ACLRs (164 pre-COVID-19, 188 during COVID-19) were included (mean age: 25.2 ​± ​10.6 years, 44% female). The overall rate of postoperative loss of motion was 15% (n = 53), and 9% (n = 31) required surgery to restore motion within 12 months of ACLR. More patients underwent surgery for loss of motion during COVID-19 compared to pre-COVID-19, which was statistically significant (12% (n = 23) vs 5% (n = 8), respectively, P = 0.02). However, a statistically significant difference in the rate of loss of motion was not detected (18% (n = 33) vs 12% (n = 20), respectively, P = 0.16). A statistically significant increased median time from injury to ACLR was observed during COVID-19 compared to pre-COVID-19 (55 vs 37 days, P <0.01). More patients were unable to achieve terminal extension (0°) at minimum 9 months postoperatively during COVID-19 compared to pre-COVID-19 (10% vs 3%, P = 0.04) and motion was worse at this interval (0°–136° vs −2°–138°, P <0.01). ConclusionSurgery for loss of motion following ACLR was more common during COVID-19. Decreased access to elective medical care, changed activity level, psychological effects, or COVID-19 itself may explain the increased rate of surgery for loss of motion during COVID-19. Level of evidenceCase series; level IV.

Lateral extra-articular tenodesis at primary ACL reconstruction increases career length in professional rugby players.

To assess the effect of preoperative and surgical factors on return to play (RTP) rates and career longevity of professional rugby athletes after primary anterior cruciate ligament (ACL) reconstruction (ACL-R). A retrospective review of a consecutive cohort of professional rugby players undergoing primary ACL-R by the senior author between 2005 and 2019 was undertaken. Athletes were included if they were under contract with a professional rugby team at the time of injury and had a minimum of 2-year follow-up. Univariate and multivariate analyses were performed to determine significant predictors of RTP rate, time and career longevity. One hundred and eighteen rugby players with 125 ACL-Rs were identified. Return to professional rugby was achieved in 115/125 (92%) of cases at an average of 9.6 months and those athletes participated at the professional level for 5.9 ± 3.4 years after ACL-R. Younger age (p = 0.006) and ACL-R with a concomitant lateral extra-articular tenodesis (LET) (p = 0.013) were predictors of a longer career. A Cox proportional hazards model that controlled for age revealed that athletes who underwent ACL-R with an LET had increased career longevity compared to those with an ACL-R without LET (hazard ratio = 2.74, p = 0.021). No factors were significantly associated with RTP rate or RTP time. In professional rugby players undergoing primary ACL-R, those having ACL-R with a concomitant LET and younger age predicted increased career longevity. Rugby players who underwent LET at the time of ACL-R had an 18% greater chance of still playing professionally at 5 years compared to those who underwent ACL-R alone. Level III.

Quadriceps tendon size does not affect postoperative strength recovery following quadriceps tendon anterior cruciate ligament reconstruction

ObjectiveThe influence of quadriceps tendon (QT) size on postoperative quadriceps strength following QT anterior cruciate ligament reconstruction (ACLR) is unclear. Therefore, this study aimed to determine the relationship between QT morphology and postoperative quadriceps strength recovery following primary ACLR using a QT autograft. MethodsPatients who underwent primary ACLR using QT autograft from 2014 to 2022 followed by a postoperative isometric strength measurement between 5 and 8 months were retrospectively reviewed. Using preoperative magnetic resonance imaging findings, the anterior–posterior (A-P) thickness, medial–lateral (M-L) width, and cross-sectional area (CSA) of the QT were measured. Postoperative residual CSA of QT was estimated based on the graft-harvest diameter. The quadriceps index (QI) was also calculated, which was determined by dividing the maximum isometric quadriceps torque on the involved side by the maximum quadriceps torque on the uninvolved side. Associations between the QI and QT morphology were assessed. Furthermore, multivariable logistic regression analysis with the addition of sex as a covariate was performed with the addition of each individual measure of QT morphology to determine the association with a QI ​≥80%. ResultsA total of 84 patients (mean age: 21.9 ​± ​7.3 years; 46 female) were included. Residual CSA showed a statistically significant positive correlation with the QI (r ​= ​0.221, p ​= ​0.043). There were no statistically significant correlations between QI and CSA, A-P thickness, or M-L width. Multivariable logistic analysis adjusting for sex demonstrated that each individual measure of QT morphology was not statistically significantly associated with a QI ​≥80%. ConclusionA statistically significant correlation between measures of preoperative QT size and postoperative quadriceps strength were not detected in patients undergoing primary QT autograft ACLR. A smaller residual QT CSA based on QT harvest diameter was weakly associated with decreased quadriceps strength 5–8 months postoperatively, but this association was not independent of sex. Future studies examining the impact of QT morphology on quadriceps strength at longer follow-up intervals are needed. Level of evidenceIV.

Increased anterior tibial subluxation and differences between anterior tibial subluxation in the lateral and medial compartments are associated with failure of primary anterior cruciate ligament reconstruction: A systematic review and meta-analysis.

The purpose of this study is to investigate whether increased anterior tibial subluxation (ATS) and differences between ATS in the lateral and medial compartments (ATSL-M) are associated with primary anterior cruciate ligament (ACL) reconstruction (ACLR) failure. PubMed, Scopus, Embase and Web of Science were systematically searched from their inception through 21 November 2023. The focus was on comparative studies reporting ATS in patients who experienced primary ACLR failure, in contrast to patients after primary ACLR with no evidence of graft failure. A random-effects model was employed to calculate the overall standardized mean difference between the two groups. A total of eight studies involving 963 patients were included in the final review. Three studies (64 cases and 171 controls) measured ATS on radiographs. The failed ACLR group exhibited a significantly increased ATS on radiographs compared to the control group (p < 0.001). Six studies (324 cases and 488 controls) measured lateral ATS on magnetic resonance imaging and five of them (285 cases and 374 controls) also measured medial ATS. The average values of lateral and medial ATS, as well as ATSL-M, were calculated and compared between the two groups. The failed ACLR group demonstrated significantly increased lateral (p < 0.001) and medial ATS (p < 0.001), the average value of lateral and medial ATS (p < 0.001) and ATSL-M (p = 0.039) compared to the control group. Increased ATS and ATSL-M are associated with primary ACLR failure. The measurement of tibiofemoral position shows promise for its application in preoperative planning and postoperative management of ACLR. Level III.

Registry-based cohort study comparing percentages of patients reaching PASS for knee function outcomes after revision ACLR compared to primary ACLR

ObjectivesReaching the Patient-Acceptable Symptom State (PASS) threshold for the Knee injury and Osteoarthritis Outcome Score (KOOS) has previously been reported to successfully identify individuals experiencing clinical success after anterior cruciate...

Single-bundle ACL combined with ALL reconstruction yields comparable outcomes in patients with varied anatomical risk factors for ACL graft failure

BackgroundAnterior cruciate ligament (ACL) graft failure is influenced by factors such as meniscal tears and tibial plateau slope. Combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction has reduced failure rates; however, its efficacy in high-risk patients remains unclear. This study hypothesized that combined ACL and ALL reconstruction would yield similar clinical outcomes in patients with varying risks of ACL failure.Patients and methodsA total of 76 patients who underwent primary single-bundle ACL reconstruction combined with ALL reconstruction between June 2018 and June 2021 were included. The medial tibial slope (MTS), lateral tibial slope (LTS), and anterior tibial translation (ATT) were measured using magnetic resonance imaging and plain radiography of the knee joint. The meniscal lesions were assessed during surgery. Preoperative clinical assessments and final follow-up were conducted using patient-reported outcome measurements (PROMs), including the International Knee Documentation Committee (IKDC) evaluation, Lysholm knee scoring scale, and Tegner Activity scale. PROMs were collected at least two years postoperatively.ResultsThe average follow-up was 32.5 ± 7.4 months. There were no significant differences in postoperative IKDC score, Lysholm score, or Tegner activity score between patients with or without medial meniscus injury (p = 0.155, 0.914, and 0.042, respectively), with or without lateral meniscus injury (p = 0.737, 0.569, and 0.942, respectively), medial tibial slope > 12° or ≤ 12° (p = 0.290, 0.496, and 0.988, respectively), or lateral tibial slope > 7.4° or ≤ 7.4° (p = 0.213, 0.625, and 0.922, respectively). No significant correlations were found between anterior tibial translation and postoperative IKDC (R = -0.058, p = 0.365), Lysholm (R = -0.017, p = 0.459), or Tegner activity scores (R = -0.147, p = 0.189).ConclusionOur study demonstrates that single-bundle ACL reconstruction combined with ALL reconstruction provides reliable and comparable clinical outcomes in patients with high-risk factors for ACL graft failure, such as increased tibial slope or meniscal injury. Our results suggest that the indications for ALL reconstruction may be expanded to include patients with a high tibial slope or meniscal injury, because these factors have been shown to contribute to increased rotational instability and high rates of ACL graft failure. Future prospective randomized controlled trials with large patient cohorts and long follow-up periods are needed to validate these findings and establish clear guidelines for patient selection and surgical decision-making.Level of evidenceLevel 3.

Qualitative and quantitative return-to-sport test battery and second anterior cruciate ligament injury risk factors

ObjectiveTo determine risk factors for second anterior cruciate ligament (ACL) injury following primary ACL reconstruction (ACLR) using return-to-sport (RTS) tests consisting of qualitative and quantitative measures in young athletes.MethodsA case–control...

Gradual stabilization and narrowing of bone tunnels following primary anterior cruciate ligament reconstruction.

The purpose of this study is to dynamically assess variations in tunnel diameters following anterior cruciate ligament reconstruction (ACLR) and investigate correlations with patient-reported outcomes (PROs) and graft maturity based on signal-to-noise quotient (SNQ). Tunnel diameter and tunnel position were measured using three-dimensional models derived from computed tomography (CT) data. Postoperative graft maturity and integration were evaluated using magnetic resonance imaging (MRI). Clinical outcomes were assessed through PROs, which included the International Knee Documentation Committee Subjective Knee Evaluation Form, Knee Injury and Osteoarthritis Outcome Scores and Lysholm scores. The correlation between tunnel enlargement extent, PROs and SNQ values, as well as correlations between confounding factors, tunnel diameter differences and SNQ were analyzed. A total of 73 participants underwent primary ACLR and scheduled follow-ups. At the segment of the articular aperture, the femoral tunnel was enlarged by 32.3% to 10.4 ± 1.6 mm (p < 0.05), and the tibial tunnel was widened by 17.2% to 9.6 ± 1.2 mm (p < 0.05) at the 6-month follow-up. At 1 year postoperatively, diameters at the articular aperture were not further increased on the femoral (n.s.) and tibial (n.s.) sides. In early postoperative follow-up, the femoral tunnel was anteriorly and distally shifted, coupled with posterior and lateral deviation involving the tibial side, exhibiting minimal migration at 1-year follow-up. The degree of tunnel widening was not correlated with PROs and SNQ values. Age, gender, body mass index (BMI), time from surgery to follow-up, concomitant injuries and autograft type were not correlated with tunnel diameter differences and SNQ. The femoral and tibial bone tunnels exhibited eccentrical widening and gradually stabilized at 1 year following ACLR. Furthermore, the enlarged bone tunnels were not correlated with unsatisfied PROs and inferior graft maturity. Level IV.

The Statistical Fragility of Lateral Extra-articular Tenodesis Research: A Systematic Review.

A P value of <.05 is often used to denote statistical significance; however, in many scenarios, this threshold is vulnerable to a small number of outcome reversals. This study joins a body of studies within the orthopaedic literature that evaluate the statistical fragility of existing research via metrics such as fragility index (FI) and fragility quotient (FQ). The purpose of this study was to investigate the statistical fragility of randomized controlled trials (RCTs) and comparative studies on the topic, given the resurgent interest in lateral extra-articular tenodesis (LET) to augment primary or revision anterior cruciate ligament reconstruction (ACLR). It was hypothesized that the outcomes reported in these studies would be statistically fragile. Systematic review; Level of evidence, 4. Comparative studies and RCTs regarding LET as an adjunct procedure to ACLR published between 2000 and 2022 were analyzed. Descriptive characteristics, dichotomous outcomes, and continuous outcomes were extracted. The FI and continuous FI (CFI) were calculated by the number of event reversals to change significance; the FQ and continuous FQ (CFQ) were calculated to normalize the fragility metrics per sample size. Of 455 studies screened, 29 studies were included (9 RCTs, 20 comparative); 79.3% of included studies were published after 2020. A total of 48 dichotomous and 265 continuous outcomes were analyzed. The median FI was 9.0 (IQR, 7.0-13.3), with FQ of 0.1 (IQR, 0.04-0.17); the median CFI was 7.8 (IQR, 4.2-19.6), with CFQ of 0.12 (IQR, 0.08-0.19). The FQ and CFQ for studies on LET with revision ACLR were larger (0.117 and 0.113, respectively) than those focused on primary ACLR (0.042 and 0.095, respectively). Studies focused on LET with primary ACLR were more fragile than those on LET with revision, which suggests that further research on the indications for LET with primary ACLR is necessary. Future orthopaedic comparative research should include fragility metrics alongside traditional P values.

Outcomes of ACL Reconstruction Utilizing Supercritical CO2-Sterilized Allografts.

Allograft tendons are perceived to have a high ACL graft failure rate in primary anterior cruciate ligament (ACL) reconstruction (ACLR). Historical series may be biased by graft processing methods that degrade the biomechanical properties of donor tendons such as irradiation. Supercritical carbon dioxide (SCCO2) is a validated method of terminally sterilizing biomaterials at physiological temperatures without irradiation, but in vivo use of SCCO2-processed tendon allografts for primary ACLR has not been reported to date. ACLR with SCCO2 allografts would result in acceptable failure rates, subjective knee scores, and clinical evaluation at 2 years postoperatively. Case series; Level of evidence, 4. Patients underwent primary ACLR with terminally sterilized SCCO2-processed human gracilis, peroneus longus, semitendinosus, tibialis anterior, and tibialis posterior tendon allografts. Patient demographics were collected, along with tendon donor age and sex. At 1 year postoperatively, subjective International Knee Documentation Committee (IKDC) and ACL-Return to Sport After Injury (ACL-RSI) scores were collected, as well as clinical evaluation. At 2 years postoperatively, the IKDC and ACL-RSI scores were repeated, and return to sports and further knee injuries were recorded. A total of 144 patients with a medianage of 26 (IQR 14) years formed the study group. Patients were predominately male (58%). The loss to follow-up rate was 8% (n = 12). The mean age of allograft tendon donors was 37 (range 17-58) years, and the majority were male (83%). The mean allograft diameter was 8.9 ± 1.0 mm. At 2 years, ACL graft failureoccurred in 5% (n = 7). All graft failureswere in patients aged ≤25 years (P = .007). Neither donor age (≤40 or >40 years) nor donor sex was associated with graft failure (P > .05). The median IKDC subjective score was 95 and ACL-RSI score was 75. There were no revisions for sepsis within the first 2 years postoperatively. SCCO2 processing of allograft tendons demonstrated satisfactory clinical and patient-reported outcomes at 24 months postoperatively in a consecutive series of patients with primary ACLR, with similar ACL graft failure rates and subjective knee scores compared with those reported in published series of hamstring tendon autograft and fresh frozen nonirradiated allograft.

Patient and Operative Risk Factors for Osteoarthritis After Primary Anterior Cruciate Ligament Reconstruction: A Cohort Study of 41,976 Patients

Background: The reported incidence of posttraumatic knee osteoarthritis (PTOA) after primary anterior cruciate ligament reconstruction (ACLR) varies considerably. Further, there are gaps in identifying which patients are at risk for PTOA after ACLR and whether there are modifiable factors. Purpose: To (1) determine the incidence of PTOA in a primary ACLR cohort and (2) identify patient and perioperative factors associated with the development of PTOA after primary ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: Data from the Kaiser Permanente ACLR Registry were used to conduct a cohort study. Patients who had undergone primary ACLR without a previous diagnosis of osteoarthritis were identified (2009-2020). The crude incidence of PTOA was calculated using the Aalen-Johansen estimator with a multistate model. The association of patient and operative factors with the development of PTOA after primary ACLR was modeled as a time to event using multistate Cox proportional hazards regression. Models stratified by age (<22 and ≥22 years) were also conducted because of the effect modification of age. Results: The study sample included 41,976 cases of primary ACLR. The incidence of PTOA was 1.7%, 5.1%, and 13.6% at 2, 5, and 10 year follow-ups, respectively. Risk factors for PTOA that were consistently identified in the overall cohort and age-stratified groups included a body mass index ≥30 versus <30 and an allograft or quadriceps tendon autograft versus a hamstring tendon autograft. Patients presenting with knee pain after ACLR were further identified when considering postoperative factors. Other risk factors for PTOA in the overall cohort included age ≥22 versus <22 years, bone–patellar tendon–bone autograft versus hamstring tendon autograft, hypertension, cartilage injury, meniscal injury, revision after primary ACLR with concomitant meniscal/cartilage surgery, multiligament injury, other activity at the time of injury compared with sport, and tibial tunnel drilling technique rather than the anteromedial portal. Conclusion: Knee pain after ACLR may be an early sign of PTOA. Surgeons should consider the adverse associations of a higher body mass index and an allograft or quadriceps tendon autograft with the development of PTOA, as these were factors identified with a higher risk, regardless of a patient’s age at the time of primary ACLR.

No Clinical Advantage of Harvesting a Patellar Bone Block Compared With All Soft-Tissue Graft in Primary Quadriceps Tendon Anterior Cruciate Ligament Reconstruction

PurposeTo compare patient-reported outcomes measurements (PROMs) and subsequent surgical interventions in patients treated with anterior cruciate ligament reconstruction (ACLR) using either quadriceps tendon autograft with a patellar bone block (bQT) or soft tissue only (sQT). MethodsAll ACLRs performed between 01.2010 and 03.2022 were prospectively followed for 24 months and retrospectively evaluated. All primary ACLRs with full 24 months of follow-up data, without any previous surgery or any additional ligamentous interventions, were matched for major ACL risk factors, including gender, age, Tegner activity level (TAL), pivoting sports, and concomitant injuries. PROMs (Lysholm score, Visual Analog Scale (VAS) for pain, and TAL) and subsequent surgical interventions were registered after 6, 12, and 24 months postoperative. Binary logistic regression was used to assess the influence of graft type, age, preinjury TAL, gender, pivoting sports and concomitant interventions on the need to undergo subsequent surgery. ResultsAfter matching, 246 patients were included in the final analysis. Both groups did not differ regarding any preoperative patient demographics or intraoperative details. At final follow-up, no significant difference in mean Lysholm score (sQT: 90.8±10.6, bQT: 91.8±10.6, p= .46), median TAL (sQT: 6 [1-10], bQT: 6 [1-10], p= .53) and VAS for pain (sQT: 0.7±1.1, bQT: 0.7±1.2, p= .70) was reported between both groups. 70.3% (sQT-A: 70.7%, bQT: 69.9%, p= .89) of patients returned to or exceeded their preinjury activity level. In terms of revision ACLR, there was no statistically significant difference between bQT (3.3%) and sQT (4.1%). Similarly, no difference was observed in contralateral ACLR (bQT: 7.3% sQT: 11.4%). Regression analysis indicated that none of the studied factors, including the use of a patellar bone block, influenced subsequent surgery, revision ACLR, or contralateral ACLR. ConclusionHarvesting an additional patellar bone block in quadriceps tendon ACL reconstruction does not seem to impact postoperative patient-reported outcomes, ACL revision- or contralateral ACL reconstruction rates. Level of EvidenceLevel 3 – Cohort Study

Correlation between Anterior Cruciate Ligament-Return to Sport after Injury Score at 6 Months after Anterior Cruciate Ligament Reconstruction and Mid-Term Functional Test Results: An Observational Study at 5-Year Follow-Up.

Background/Objectives: Evaluations allowing patients to return to sport (RTS) after anterior cruciate ligament reconstruction (ACLR) should be multimodal, including a psychological evaluation. The goal of this study was to determine if there is a correlation between the ACL-return to sport after injury (ACL-RSI) score at 6 months post-ACLR and mid-term functional results. Methods: A total of 498 patients were assessed 6 months after primary ACLR using a composite test including isokinetics, hops, and ACL-RSI. A minimum of 3 years of follow-up was necessary. At the last follow-up, each patient completed clinical and functional evaluations, including the subjective International Knee Documentation Committee (IKDC) score, Tegner Activity Scale, Self Knee Value (SKV), and ACL-RSI score. The results were compared overall and item by item. Results: At the last follow-up, the mean SKV, Tegner, IKDC, and ACL-RSI scores were 86.8 ± 14.3%, 6 ± 2.1, 77 ± 11.9%, and 68.8 ± 25.7%, respectively. A significant correlation existed between the 6-month ACL-RSI score and each functional test (respectively, ρ = 0.189 p < 0.001; ρ = 0.174 p < 0.001; ρ = 0.237 p < 0.001). The ACL-RSI score was significantly higher than at 6 months after surgery (p < 0.001). Over half (59.2%) of the cohort returned to an equal or greater level of activity, and there was a significant correlation between the 6-month ACL-RSI score and post-surgery level of activity. Conclusions: Patients with better ACL-RSI scores at 6 months post-ACLR have better functional results in the medium term and are more likely to RTS. Our results show a correlation between psychological factors at 6 months, measured through the ACL-RSI score, and activity level at mid-term follow-up. This study underlines the relationship between RTS and psychological effects, and the importance of ACLR rehabilitation to focus on decreasing apprehension and fear.

Incidence of Osteoarthritis Between ACL Reconstruction With Different Graft Types and Between ACL Reconstruction and Repair: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

Variation in stiffness, fixation methods, and donor-site morbidity after anterior cruciate ligament reconstruction (ACLR) with different graft types and with anterior cruciate ligament suture repair (ACLSR) can lead to differences in dynamic knee laxity and consequent differences in posttraumatic osteoarthritis (PTOA) development. To compare the incidence of PTOA between different graft types used for primary ACLR and between primary ACLR and ACLSR. It was hypothesized that the incidence of PTOA would vary between ACLR with different autografts and allografts and between ACLR and ACLSR. Systematic review; Level of evidence, 1. A search of the literature was performed to identify all randomized controlled trials (RCTs) comparing radiographic evidence of PTOA after ACLR between different graft types-hamstring tendon (HT) autograft, bone-patellar tendon-bone (BPTB) autograft, quadriceps tendon autograft, and allograft-and between ACLR and ACLSR. The minimum follow-up was 2 years. Study quality was assessed using the modified Coleman Methodology Score. A meta-analysis was performed to determine whether there was a difference in the incidence of PTOA between the different graft types and between ACLR and ACLSR. Eleven randomized controlled trials were included in the meta-analysis-HT: 440 patients (mean follow-up, 9.7 years); BPTB: 307 patients (mean follow-up, 11.8 years); allograft: 246 patients (mean follow-up, 5 years); ACLSR, 22 patients (5 years). No study reporting the incidence after ACLR with quadriceps tendon was included. The study quality ranged from 70 to 88. The meta-analysis indicated no significant difference in the incidence of PTOA between graft types used for ACLR and between ACLR and ACLSR (risk ratios: HT vs BPTB, 1.05; HT vs allograft, 0.81; BPTB vs allograft, 0.82; HT vs ACLSR, not estimable [P > .05 for all]). The combined number of patients with PTOA in all studies per graft type showed that patients who underwent ACLR with a BPTB autograft had the highest percentage of PTOA (HT, 23.4%; BPTB, 29.6%; allograft, 8.1%; ACLSR, 0%). However, excluding studies with a follow-up <5 years resulted in similar outcomes for patients with an HT autograft and a BPTB autograft. This meta-analysis reported no difference in the incidence of PTOA between graft types used for ACLR and between ACLR and ACLSR. More research is necessary to make a reliable conclusion about which technique is associated with the lowest incidence of PTOA after ACL surgery.