Background: Adolescents experience the highest rates of both ipsilateral and contralateral reinjury following anterior cruciate ligament (ACL) reconstruction (ACLR). Psychological readiness has been shown to be associated with ACL reinjury although the exact relationship is unclear because prior investigations have neither tracked its evolution over time nor stratified results by age and sex. Purpose: To perform an age- and sex-specific, longitudinal analysis of the relationship between Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) score and the risk of ipsilateral/contralateral ACL injury in adolescents. Study Design: Cohort study; Level of evidence, 3. Methods: A consecutive cohort of adolescents (<18 years old) who underwent primary ACLR at a single center completed the ACL-RSI preoperatively and at 3, 6, and 9 months. Functional strength and jump metrics were also collected at 9 months. Return to play (RTP) and the incidence of second ACL injury were recorded at 5 years. Differences in ACL-RSI were evaluated and receiver operating characteristic curves were used to quantify the discriminative ability of the ACL-RSI score. Results: There were 539 adolescents included. The RTP rate was 89.7% at a mean time of 10.8 ± 3.1 months. The rate of second ACL injury was 22.2% (ipsilateral 9.7%; contralateral 12.5%) at 5 years. Adolescents who sustained a contralateral ACL injury had higher ACL-RSI scores at 9 months for male patients (85.1 ± 14.4 vs 76.7 ± 17.6; P = .004) and at 6 months for female patients (79.9 ± 15.2 vs 67.8 ± 20.2; P = .017) than those who remained uninjured. In contrast, male adolescents who suffered graft rupture recorded lower 9-month ACL-RSI scores than uninjured peers (66.2 ± 18.5 vs 76.7 ± 17.6; P = .003). The ACL-RSI was predictive of ipsilateral reinjury in male adolescents but not in females. Conclusion: Serial ACL-RSI scores yield distinct, sex-specific risk profiles in adolescents. Low scores during rehabilitation identify athletes vulnerable to ipsilateral graft failure, whereas rapidly rising, high scores indicate those at risk for contralateral reinjury. This highlights the need to interpret the ACL-RSI score taking age and sex into consideration.

Background: Psychological readiness encompasses fear of reinjury, confidence in performance, and risk appraisal. It is increasingly recognized as a critical factor influencing return to play (RTP) after anterior cruciate ligament (ACL) reconstruction (ACLR). Elite athletes typically exhibit high self-efficacy and a strong athletic identity while also facing intense external pressure to return. While these dynamics undoubtedly influence their response to injury and psychological recovery after ACLR, the precise differences in psychological readiness between elite and nonelite athletes have not been reported. Purpose: To compare psychological readiness between elite and nonelite athletes after primary ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 756 participants were included in this study. There were 252 elite athletes and 504 propensity score–matched, nonelite athletes (1:2 ratio). Elite athletes were those who played professional sport, represented their country at international competitions, or played intercounty-level Gaelic Games. Psychological readiness was compared between groups preoperatively and at 3, 6, and 9 months postoperatively using the ACL Return to Sport after Injury scale (ACL-RSI). Participants were contacted at 1 year and 2 years postoperatively to record if they had returned to play. Multivariable analysis was used to identify factors (eg, age, sex, elite level) associated with ACL-RSI scores at 9 months. Results: Preoperative ACL-RSI scores did not differ significantly between elite and nonelite groups (50.6 ± 27.4 vs 48.1 ± 26.6; P = .28). However, elite athletes had higher scores at 3 months (58.6 ± 23.4 vs 53.1 ± 21.9; P < .001), 6 months (67.4 ± 19.9 vs 63.1 ± 19.4; P = .01) and 9 months (72.7 ± 19.9 vs 68.6 ± 19.2; P = .009). Elite athletes had significantly higher RTP rates at 1 year (86% vs 69%; P < .001) and 2 years (94.3% vs 86.7%; P < .002). Multivariate analysis revealed that International Knee Documentation Committee score at 9 months (β = 1.10; 95% CI, 0.95-1.25; P < .001) and male sex (β = 3.7; 95% CI, 0.8-6.6; P < .01) were most associated with increased ACL-RSI scores at 9 months. After adjusting for other factors, elite status was not an independent predictor of psychological readiness. Conclusion: Our study demonstrated that preoperative ACL-RSI scores were comparable between elite and nonelite athletes. However, elite athletes had consistently higher ACL-RSI scores during rehabilitation and ultimately greater RTP rates. Knee function and male sex are the strongest predictors of ACL-RSI score. Being an elite athlete is not a primary predictor of psychological readiness, and psychological intervention should be considered in all athletes.

BACKGROUND:The risk of posttraumatic arthritis is elevated after anterior cruciate ligament (ACL) injury, and this can influence follow-up patient-reported outcome measures (PROMs). Biomarkers of chondral and matrix metabolism may represent a means of quantitatively evaluating the posttraumatic arthritis pathological process. PURPOSE:To assess for a longitudinal association between 3 systemic (blood and/or urine) biomarkers of chondral and matrix metabolism as measured on the day of ACL reconstruction with poor PROMs 6 years later. STUDY DESIGN:Descriptive laboratory study. METHODS:From a prospective longitudinal study, urine and serum samples were taken immediately before primary ACL reconstruction in 642 patients (mean age, 25.02 years; 60.3% men). Three biomarkers of chondral and matrix metabolism were measured using immunoassays: urinary C-terminal cross-linked telopeptide of type 2 collagen (u-CTX-II), serum N-propeptide of collagen 2A (s-PIIANP), and serum matrix metalloproteinase-3 (MMP-3). Six years postoperatively, patients completed the International Knee Documentation Committee (IKDC) Subjective Knee Form and Knee injury and Osteoarthritis Outcome Score-4 (KOOS-4) PROMs. PROMs were dichotomized based on Patient Acceptable Symptom State (PASS) thresholds. After exclusion of patients with outlier biomarker values and missing data, univariate (n = 411 for KOOS-4 and n = 419 for IKDC) and multivariate (n = 366 for KOOS-4 and n = 373 for IKDC) logistic regression models were developed with baseline biomarker concentrations and surgical and demographic parameters as predictive variables. RESULTS:In the multivariate model, higher baseline s-MMP-3 (OR, 0.98; P = .009) and increased articular cartilage pathology at surgery (OR, 0.87; P = .040) were associated with not achieving a KOOS-4 PASS. Higher baseline s-MMP-3 (OR, 0.98; P = .031), increased articular cartilage pathology at surgery (OR, 0.88; P = .045), and higher preoperative body mass index (BMI) (OR, 0.91; P = .027) were associated with not achieving a IKDC PASS. A medial meniscus tear that was resected was associated with achieving the IKDC PASS relative to no medial meniscus tear (OR, 3.34; P = .017). In the univariate modeling, older age and higher BMI were additionally associated with not achieving a KOOS-4 PASS (all P≤ .017). In the IKDC univariate modeling, lower baseline s-PIIANP, higher u-CTX-II, increasing age, and a lower preoperative Marx score were additionally associated with failing to achieve the PASS threshold (all P≤ .043). CONCLUSION:Increased s-MMP-3 concentration on the day of surgery was associated with failing to achieve the PASS threshold for both the KOOS-4 and IKDC PROMs at the 6-year time point after ACL reconstruction. CLINICAL RELEVANCE:This day of surgery blood test may be helpful in identifying patients at risk of a poor outcome 6 years after ACL reconstruction. In turn, this could help define a target group for evaluating interventions aimed at preventing posttraumatic arthritis.

INTRODUCTION:This study reports Revision Anterior Cruciate Ligament Reconstruction (R-ACLR) outcomes using Bone-Patellar Tendon-Bone (BPTB) vs. Hamstring (HT) autografts with and without lateral extra-articular tenodesis (LEAT) in a cohort of level 1 athletes. METHODS:A consecutive cohort of 262 athletes who underwent R-ACLR between 2014 and 2018 were analysed. The decision to augment revision ACLR with LEAT was guided by younger age and generalised hypermobility. There were 157 patients in the BPTB cohort (BPTB = 53 vs. BPTB + LEAT = 104) and 105 patients in the HT cohort (HT = 32 vs. HT + LEAT = 73). Return to Play (RTP), ipsilateral/contralateral ACL injuries and patient-reported outcome measures (International Knee Documentation Committee Score (IKDC), Marx) were assessed at 2 years. RESULTS:The mean age was 25.4 +/- 6.3 years and 84.4% of patients were male. RTP rates (BPTB +/- LEAT: 65.2% vs. HT +/- LEAT: 62.8%; p=.400) and time to RTP (13.3 ± 5.7 vs. 12.4 ± 6.1 months) were comparable. Increasing age was independently associated with reduced odds of return to play, with each additional year associated with a 6.9% reduction in the odds of RTP (OR 0.93, 95% CI 0.89-0.98; p = 0.005). There was no statistically significant difference in graft re-injury rates with or without LEAT (BPTB vs. BPTB + LEAT: 1.9% (1/52) vs. 2.9% (3/2.9), p=.720) and (HT vs. HT + LEAT: 6.3% (2/30) vs. 1.4% (1/72), p=.163). There was no statistically significant difference in IKDC score (BPTB: 83.3 +/- 11.7 vs. HT: 83.6 +/- 13.9, p = .885). Both cohorts demonstrated a reduction in Marx score from their preoperative levels (BPTB +/- LEAT: 10.7 to 8.1 vs. HT +/- LEAT: 11.1 to 8.7). CONCLUSION:This study demonstrated that using ipsilateral BPTB and HT autografts for R-ACLR in level 1 athletes resulted in no statistically significant difference in RTP, re-injury and patient-reported outcomes. There was also no difference in re-injury rate in the group that received LEAT. Interestingly, although patients in the LEAT group were younger and had a lower incidence of chondral injuries, this did not translate into improved patient-reported outcomes. Notably, all patients' activity levels were substantially reduced after revision ACLR, regardless of the type of graft used. LEVEL OF EVIDENCE 3: Cohort study.

BACKGROUND:Meniscal tears occur at the time of anterior cruciate ligament (ACL) injury in 55% to 65% of patients. These tears exhibit different healing patterns and behavior compared with meniscal tears in a stable knee. The optimal management of different medial, lateral and bicompartmental tears during primary ACL reconstruction (ACLR) has yet to be defined. PURPOSE:To evaluate the reoperation rates associated with different meniscal treatment strategies and analyze the effect of medial, lateral, and bicompartmental meniscal tears on ACLR outcomes. STUDY DESIGN:Cohort study; Level of evidence, 2. METHODS:This investigation included 1137 patients undergoing primary ACLR with a concomitant meniscal injury. Patients with chondral defects and multiligament knee injuries were excluded. Meniscal treatments were divided into 3 categories: left in situ (LIS), partial meniscectomy (PM), and repair. Reoperation was defined as the primary endpoint, and multivariable analysis was conducted to identify patient and tear characteristics associated with reoperation. The influence of different treatment strategies on return to play (RTP), ACL reinjury rate, and patient-reported outcome measures (PROMs) was reported at 2 years. The PROMs recorded were the International Knee Documentation Committee (IKDC) score, the Marx Activity Rating Scale, and the Anterior Cruciate Ligament-Return to Sport after Injury score. RESULTS:The mean age was 24.0 ± 6.9 years, and 76% of patients were male. Most injuries were noncontact (64.9%), commonly resulting from pivoting/sidestepping (50.1%). No significant differences in injury mechanism, playing surface, or footwear type were found between medial, lateral, or bicompartmental tears. Reoperation rates for patients were low for lateral (1.3%), medial (2.6%), and bicompartmental tears (3.2%) LIS at the time of ACLR. The rate of reoperation/subsequent meniscectomy for medial meniscal repairs (14.8%) was significantly higher than for other medial treatments (hazard ratio 12.8; P < .001). Patients who underwent meniscal repair with a concomitant tear in the opposite compartment (repair + PM/LIS) had the highest reoperation rates (16.7%) and lowest RTP rates (60%). IKDC scores were significantly lower for patients who underwent lateral meniscal repair (81.1 ± 15.3) compared with other types of lateral meniscal management (P < .027). ACL reinjury rate was not influenced by meniscal treatment. A higher preoperative Marx score increased the risk of reoperation in all groups. CONCLUSION:Stable meniscal tears LIS during ACLR had low reoperation rates and good patient-reported outcomes, including patients with bicompartmental tears. Medial meniscal repairs had the highest risk of reoperation, particularly when another tear was present in the lateral compartment. Lateral meniscal repairs were associated with lower IKDC scores compared with other lateral meniscal treatment strategies.

BACKGROUND:Anterior cruciate ligament (ACL) injuries and reconstruction are associated with alterations in chondral homeostasis and posttraumatic osteoarthritis. Biomarkers of chondral metabolism may have a role in quantitatively evaluating this phenomenon. PURPOSES:To describe changes in 3 systemic biomarkers of chondral metabolism and extracellular matrix remodeling during the first year after ACL reconstruction and to identify factors associated with biomarker concentrations at the baseline and 12-month postoperative timepoints. STUDY DESIGN:Controlled laboratory study. METHODS:From a longitudinal study, urine and serum samples were taken immediately before primary ACL reconstruction and at 6 and 12 months postoperatively. A total of 666 patients provided samples (mean ± SD age, 24.9 ± 7.2 years; 60.5% male). Immunoassays were used to measure concentrations of urinary C-terminal cross-linked telopeptide of type 2 collagen (CTX-II), a marker of type 2 collagen degradation; serum N-propeptide of collagen IIA (PIIANP), a marker of type 2 collagen synthesis; and serum matrix metalloproteinase 3 (MMP-3), a mediator of extracellular matrix remodeling. Linear mixed modeling and linear regression were used for data analysis. RESULTS:Urinary CTX-II concentrations decreased by 25% (95% CI, 19%-31%) from baseline to 6 months and by 37% (95% CI, 22%-42%) from baseline to 12 months, respectively (P < .001). Serum PIIANP increased by 40% (95% CI, 34%-47%) from baseline to 6 months (P < .001) with no significant change between 6 and 12 months. Serum MMP-3 increased by 35% (95% CI, 29%-42%) and 44% (95% CI, 37%-52%) from baseline to 6 months and from baseline to 12 months respectively (P < .001). At the baseline timepoint, age, body mass index (BMI), sex, and time from injury to surgery were factors associated with biomarker concentrations. At the 12-month timepoint, age, sex, BMI, and time from injury to surgery were associated with biomarker concentrations. CONCLUSION:Decreasing urinary CTX-II concentrations coupled with increasing serum PIIANP concentrations may suggest a reparative chondral response within the first 12 months after ACL reconstruction. Increasing serum MMP-3 concentrations suggested persistent and progressive extracellular matrix remodeling during this same period. Predominantly nonmodifiable demographic factors were associated with baseline and 12-month concentrations of the 3 biomarkers. CLINICAL RELEVANCE:Biomarkers of chondral metabolism may have future prognostic or decision-making roles in the management of patients with ACL injury. This could include predicting posttraumatic arthritis.

PURPOSE:Bone-patellar tendon-bone (BPTB) and Hamstring (HT) autografts are commonly used for anterior cruciate ligament reconstruction (ACLR). Concerns exist regarding postoperative anterior knee pain (AKP) and kneeling discomfort with BPTB grafts. However, many studies solely report the presence/absence of anterior knee pain, without assessing its clinical significance in terms of functional limitation or impact on quality of life. METHODS:This study prospectively analysed 1407 patients undergoing primary ACLR with BPTB or HT autografts. Knee pain prevalence, severity, and location were measured at 6 months, 1 year, 2 years, and 5 years postoperatively using a pain questionnaire. Patient-reported measures (Knee Injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], International Knee Documentation Committee [IKDC] and Marx) and return to play (RTP) rates were also collected to evaluate knee symptoms, function and activity levels. Multivariable regression identified factors associated with knee pain at each time point. RESULTS:The mean age was 24.5  ±  7.1 years, with 74.3% male. BPTB grafts were used in 81% (n = 1145) and HT in 19% (n = 262). At 6 months, the BPTB group reported a higher prevalence of AKP (26% vs. 6%, p < 0.001). There was no difference between graft types at 1 year and 2 years postoperatively. At 5 years, the BPTB group were 1.59 times more likely to report pain, although most pain was mild and there was no significant differences in KOOS, WOMAC, IKDC, Marx scores or RTP rates. Female patients (OR 1.41, p < 0.035) and BPTB grafts (OR 1.78, p < 0.004) were associated with knee pain at 6 months. At 5 years, older age (OR 1.06, p < 0.001), BPTB grafts (OR 1.59, p < 0.027), and medial femoral condyle chondral pathology (OR 1.7, p < 0.020) increased the odds of having pain. CONCLUSION:BPTB grafts are associated with early AKP, which improves over time. AKP related to BPTB is mild and does not affect activity levels, sports participation or quality of life. Mild AKP should not deter surgeons from using BPTB autografts for ACLR, given the other advantages of this graft choice. LEVEL OF EVIDENCE:Level II, prospective study.

Objective: To compare urinary C-terminal cross-linked telopeptide of type II collagen (u-CTX-II) concentrations and trends as measured by two different commercially available enzyme-linked immunosorbent assays (ELISA) in a cohort of patients in the first year following anterior cruciate ligament (ACL) reconstruction. Design: 22 ACL-injured patients undergoing reconstructive surgery (mean age 25.2 (SD 8.0) years; 12 (54.5 %) male) had urine samples taken on the day of surgery (baseline) and at 6 and 12 months post-operatively. Concentrations of u-CTX-II were measured using the CloudClone (R) and the CartiLaps (R) ELISA. u-CTX-II concentrations were normalized to urinary creatinine (Cr). Results: The u-CTX-II concentrations were significantly different between the 2 assays at each timepoint (p <= 0.01). When measured using the CloudClone (R) Assay, mean (standard error) u-CTX-II concentrations were 26.5 (2.5) ng/mmol Cr, 29.4 (3.8) ng/mmol Cr and 40.6 (6.9) ng/mmol Cr at the baseline, 6-month and 12-month timepoints respectively. When measured using the CartiLaps (R) Assay, at the same respective timepoints, u-CTXII concentrations were 981.2 (256.5) ng/mmol Cr, 867.0 (234.3) ng/mmol Cr and 764.3 (220.3) ng/mmol Cr. Concentrations of u-CTX-II using the CloudClone (R) Assay increased with time (p = 0.04). Concentrations of uCTX-II using the CartiLaps (R) Assay decreased over time (p = 0.2). Conclusion: Using two commercially available assays, u-CTX-II differed significantly in terms of both concentration and trends in the first year following ACL reconstruction. The specific assay used is critical to consider when interpreting results and has implications for pooling data and meta-analysis.

Background:Quadriceps tendon (QT) autograft has emerged as an increasingly popular graft for anterior cruciate ligament reconstruction (ACLR). The modified Star Excursion Balance Test (MSEBT) measures dynamic balance and is frequently used in evaluating preparedness to return to sport as part of return-to-sport test batteries. There is limited information available about the MSEBT performance of patients who have undergone ACLR with QT autograft. Hypothesis/Purpose:The purpose was to compare the MSEBT performance at 12 months after primary ACLR of patients with QT autografts with the performance of patients with hamstring tendon (HS) autografts. It was hypothesized that there would be a difference in the 2 groups due to harvest from either an extensor or a flexor of the knee joint. Study Design:Cohort study; Level of evidence, 3. Methods:The cohort consisted of 132 patients (44 patients with QT, 88 patients with HS) who had undergone primary ACLR with either a QT or HS autograft, were <30 years of age at the time of surgery, and had participated in sports regularly before injury. Patients with contralateral anterior cruciate ligament injury or an additional lateral extra-articular tenodesis were excluded. The mean age of the patients was 22.1 years, and 18% were female. The anterior reach, posterolateral reach, and posteromedial reach on the MSEBT were recorded at 12 months postoperatively and normalized to leg length. The limb symmetry index (LSI) and the composite score (CS) were calculated for each measurement. Patient-reported outcome measures were also collected. Results:There were no significant differences between the mean LSI and the CS of the QT and HS groups for any reach direction of the MSEBT (LSI: QT = 99.9 and HS = 98.9 for anterior reach, QT = 100.9 and HS = 100.2 for posterolateral reach; QT = 101.1 and HS = 100.8 for posteromedial reach, CS: QT = 96.6 and HS = 96.9). Patient-reported outcome measures also showed no significant difference. Conclusion:There were no differences in symmetry between QT and HS grafts in MSEBT performance at 12 months, with both patient groups having >98% limb symmetry in each reach direction.

Background:Despite advances in modern surgical techniques, return-to-play (RTP) rates after revision anterior cruciate ligament reconstruction (R-ACLR) often fall short of patients' expectations. There is growing awareness that a patient's psychological recovery is as important as the functional recovery of their knee. Purpose/Hypothesis:The primary purpose of this study was to determine the RTP rate and identify the barriers to RTP after R-ACLR. Secondarily, we compared the progression of psychological readiness (using the Anterior Cruciate Ligament-Return to Sport after Injury [ACL-RSI] scale) throughout rehabilitation between those who achieved RTP and those who did not. Finally, we assessed if RTP could be predicted for patients aged <23 years and patients aged ≥23 years based on their ACL-RSI scores at different time points during rehabilitation. Study Design:Case-control study; Level of evidence, 3. Methods:This investigation included 301 patients who underwent R-ACLR at our institution. Preoperatively, patients completed a questionnaire detailing their demographic characteristics and target level of RTP. The ACL-RSI scale was also administered preoperatively and at 3 months, 6 months, and 9 months. At 2 years postoperatively, patients indicated whether or not they had returned to play. Those who did not return provided their reasons for not doing so. Results:The mean age was 25.4 ± 6.3 years, and 84.5% of patients were male. Although 95.1% of patients undergoing R-ACLR intended to return to play before surgery, only 63.4% achieved this goal at 2-year follow-up. The main barriers to RTP were a fear of reinjury (44%), a lack of confidence in performance (13%), and ongoing knee pain (11%). The mean preoperative ACL-RSI score was significantly higher in patients who returned to play than in those who did not (51.2 ± 23.4 vs 42.6 ± 23.3, respectively; P = .027), indicating greater psychological readiness to RTP. The mean ACL-RSI score was also significantly higher in those who achieved RTP at 3 months, 6 months, and 9 months. A preoperative ACL-RSI score of 42.9 points predicted RTP in patients aged <23 years, with a sensitivity of 76% and a specificity of 77% (area under the curve = 0.73). The ACL-RSI score was able to predict RTP at all time points, demonstrating the most accuracy preoperatively and at 6 months postoperatively. At 6 months, a cut-off score of 60.4 points predicted RTP in patients aged <23 years (sensitivity = 62%; specificity = 81%), and a cut-off score of 56.7 points predicted RTP in patients aged ≥23 years (sensitivity = 54%; specificity = 77%). Conclusion:Psychological readiness, especially fear of reinjury, was a significant barrier to RTP after R-ACLR. Patients with lower psychological readiness who were less likely to return to play could be detected using the ACL-RSI scale.

Background:The Gaelic games, specifically Gaelic football, hurling, and camogie, are high-intensity, level 1 field sports. However, there is a lack of data regarding the outcomes of anterior cruciate ligament reconstruction (ACLR) in Gaelic games players. Purpose:To evaluate the rates of return to play (RTP), ACL graft reinjury, contralateral ACL injury, and patient-reported outcome measures (PROMS) in a cohort of Gaelic footballers and hurling/camogie players at 2 years after ACLR. Study Design:Cohort study; Level of evidence, 2. Methods:A consecutive cohort of 1891 Gaelic games players who underwent primary ACLR between 2014 and 2018 was included. Patients were contacted at 2 years postoperatively with an overall follow-up rate of 93.4%. The rate of RTP, subsequent ACL injury, and PROMS were recorded. The PROMS evaluated were the Marx score, the ACL-Return to Sport after Injury (ACL-RSI), and the International Knee Documentation Committee (IKDC) score. Results:The mean age was 23 ± 6 years, and 73.3% of athletes were male. RTP rates were 87.8% for Gaelic football and 89.5% for hurling/camogie, with 72.7% and 76.3% of athletes returning to an equivalent or higher level of performance, respectively. Female Gaelic footballers had a slightly lower RTP rate than males (83.8% vs 89.1%; P < .016). The mean time to RTP was 10.8 ± 4 months. The rate of bone-patellar tendon-bone (BPTB) autograft reinjury was 3.3% (51/1547) versus 15.3% (33/216) for hamstring (HT) autografts (P < .001). Senior intercounty (elite) players had the lowest rate of contralateral ACL injury (8.1%, 14/173). Gaelic footballers and hurling/camogie players reported good outcomes with mean IKDC scores of 86.9 ± 9.8 versus 87.9 ± 8.9, (P = .064), mean Marx scores of 11 ± 4.7 versus 11.3 ± 4.6 (P = .309), and mean ACL-RSI scores of 74.1 ± 23.5 versus 75.8 ± 24.2 (P = .321), respectively. Conclusion:RTP rates among Gaelic games players were high, with the majority returning to an equivalent/higher level of performance. The rate of BPTB graft reinjury was low, considering the injury risk associated with returning to level 1 sport. Younger patients and those who underwent HT autograft reconstruction were at the highest risk of ACL graft reinjury. Overall, Gaelic games players reported good knee function and outcomes after ACLR.

BACKGROUND:Changes in systemic biomarkers of chondral metabolism have been identified after anterior cruciate ligament (ACL) reconstruction. Patients with extremely high biomarker concentrations (outlier patients) are often observed and may represent a group at high risk for posttraumatic arthritis. It is unclear if outlier status changes over time, and if it can be explained by patient, injury, and surgical factors. PURPOSE:To evaluate outlier status changes over time for 3 biomarkers of chondral metabolism after ACL injury and reconstruction and describe factors associated with outlier status. STUDY DESIGN:Cohort study; Level of evidence, 2. METHODS:Patients from a prospective longitudinal study were included. Urine and serum samples were taken immediately before primary ACL reconstruction and at 6 and 12 months postoperatively. A total of 666 patients provided samples (mean age, 24.9 years; 60.5% male). Concentrations of urinary C-terminal cross-linked telopeptide of type 2 collagen (u-CTX-II), serum N-propeptide of collagen 2A (s-PIIANP), and serum matrix metalloproteinase 3 (s-MMP-3) were measured using immunoassays. Outlier status was defined as values above quartile 3 plus 1.5 times the interquartile range for each biomarker. Multivariable logistic regression models were developed with biomarker outlier status as the dependent variable and patient, injury, and surgical factors as explanatory variables. RESULTS:At the baseline time point, the proportion of outliers was 9.29% for u-CTX-II, 1.97% for s-PIIANP, and 12.42% for s-MMP-3. Outlier patients at baseline were commonly also outliers at one or both of the future time points in terms of u-CTX-II (88.3%) and s-MMP-3 (82.93%). In contrast, for s-PIIANP outlier patients at baseline, only 15.38% were outliers at a future time point. It was uncommon for nonoutlier patients at baseline to become an outlier at either of the future time points (u-CTX-II: 6.83%; s-PIIANP: 2.32%; s-MMP-3: 2.08%). Patient and surgical factors had poor ability to discriminate between outlier and nonoutlier patients for s-PIIANP (Tjur R2 = 0.056) and s-MMP-3 (Tjur R2 = 0.013). However, for u-CTX-II (Tjur R2 = 0.598), younger age, shorter time from injury to surgery, lower body mass index, and male sex were independently associated with outlier u-CTX-II concentrations at baseline. CONCLUSION:Outlier patients were observed when measuring all 3 systemic biomarkers of chondral metabolism after ACL reconstruction. For s-PIIANP and sMMP-3, outlier status was poorly explained by patient or surgical factors, but for u-CTX-II, outlier status could, in part, be explained by patient and surgical factors. These results support longitudinal biomarker analyses, given that outlier status can change over time, and this may not be identified in cross-sectional study designs.

This classic discusses Marcel Lemaire's original publications in the context of modern surgical practice, including a description of his original lateral extra-articular tenodesis. Previously published in French, these translations shed light on his revelations regarding the anterior cruciate ligament's role in knee stability and his detailed insights into the ressaut rotatoire or the pivot shift phenomenon. We track the evolution of Lemaire's procedure since the publication of his original technique in 1967 which used a nylon cord superficial to the lateral collateral ligament followed by cast immobilisation for one month. We report his patient outcomes as he refines his methods through experiential learning. Lemaire's fundamental concepts in relation to anterior cruciate ligament deficiency remain relevant in contemporary clinical practice. Furthermore, the "modified Lemaire technique" has emerged as one of the preferred methods for lateral extra-articular tenodesis. We hope that disseminating his thoughts to a wider audience will help enlighten the ongoing debate regarding the management of rotatory instability. LEVEL OF EVIDENCE: V - Expert Opinion.

This classic discusses Arthur E. Ellison’s (1926-2010) contributions to our understanding of anterolateral rotatory laxity of the knee. Ellison was a distinguished orthopaedic surgeon and one of the founding members of the American Orthopaedic Society for Sports Medicine (AOSSM). He served as the team physician for the United States Ski team and Williamsburg football team. Ellison’s publications focused on the pathodynamics of knee stability, shedding light on the biomechanical functions of the iliotibial band. This led to the development of his lateral extra-articular procedure designed to control excessive tibial rotation in the anterior cruciate ligament (ACL) deficient knee. His work has made a significant contribution to our understanding of knee stability today and many surgeons still use a modified version of Ellison’s original technique to augment ACL reconstruction.This article summarises Ellison’s original publications and the first description of his operative technique. The impact of his work is discussed in the context of modern practice. The aim of this study is to add these valuable insights to the current discussion regarding the optimal method for lateral extra-articular tenodesis. Level of Evidence V - Expert Opinion

Objectives: To describe and evaluate the preliminary validity of a novel scoring system for assessing the physical activity of patients after anterior cruciate ligament (ACL) reconstruction. Methods: The Sports and Physical Activity (SPA) scale consists of thirty options of sports and physical activities, followed by four frequency options for each option selected. Factors used to develop the scoring system were frequency of participation and intensity of the sports or physical activities. Possible scores ranged from a low of 0 to a high of 24. The scale was assessed for validity and responsiveness. Results: The study cohort included 418 primary ACL reconstructed patients 2 years after surgery, and a subgroup of 183 patient 5 years after surgery. The mean and median SPA scores for the cohort were 12.35 (+/- 6.95) and 12, respectively. There was no statistically significant difference between the scores of men and women (U = 21,541.0, p = 0.921). The SPA scale had a small but statistically significant inverse correlation with age (r(s) = -0.2, p = <0.001), indicating divergent validity. Patients who had returned to sport had a statistically significantly higher score (U = 21593.5, p = <0.001), and there was a statistically significant difference between scores of the three current sports status groups (H = 19.99, p value = <0.001) indicating convergent validity. Construct validity was indicated with a statistically significant correlation with the Marx scale (r(s) = 0.422, p value= <0.001). In a subgroup (n = 183) of the patient sample, comparison between scores at 2-years (13.27 +/- 7.02) and 5-years (12.11 +/- 7.88) found a statistically significant decline (p= <0.001). However, this decline was smaller than the decline seen in the Marx score between 2 and 5 years (11.11 +/- 4.07 and 9.30 +/- 4.52 p= <0.001). Conclusion: Preliminary validity was found for the SPA scale. Women and men were found to be participating in a similar amount of activity 2 years post ACL reconstruction, despite return to sport differences between men and women being well documented. The scores of the SPA scale showed a statistically significant decrease over time with a negligible effect size.

Anterior cruciate ligament (ACL) injuries continue to increase in incidence despite extensive research into prevention strategies. Many extrinsic and intrinsic risk factors for sustaining ACL injuries have been identified and continue to be investigated. Extrinsic risk factors for ACL injury relate to the athlete's environment, such as the shoe-surface interaction, weather conditions, and sport played. Intrinsic risk factors relate to the athlete's sex, hormones, knee anatomy, landing and pivoting biomechanics, and neuromuscular control. Recent research has highlighted the role of the bony morphology of the proximal tibia and distal femur on primary ACL injury risk, as well as the risk for ACL graft failure. Sex differences in bony and ligamentous morphology of the knee, neuromuscular control, and hormonal factors, such as serum relaxin levels and variations within the menstrual cycle, have been correlated with a higher risk of noncontact primary ACL injuries in female athletes compared with male athletes.

Background: The impact of a physically demanding occupation on clinical outcomes after anterior cruciate ligament (ACL) reconstruction (ACLR) is largely unknown. Purpose/Hypothesis: The purpose of this study was to assess the influence of occupation on 12-month outcomes after ACLR in male patients. It was hypothesized that patients undertaking manual work would not only have better functional outcomes in terms of strength and range of motion but also higher rates of joint effusion and greater anterior knee laxity. Study Design: Cohort study; Level of evidence, 3. Methods: From an initial cohort of 1829 patients, we identified 372 eligible patients aged 18 to 30 years who underwent primary ACLR between 2014 and 2017. Based on a preoperative self-assessment, 2 groups were established: patients engaged in heavy manual occupations and those engaged in low-impact occupations. Data were collected from a prospective database including effusion, knee range of motion (using side-to-side difference), anterior knee laxity, limb symmetry index for single hop and triple hop, International Knee Documentation Committee (IKDC) subjective score, and complications up to 12 months. Because of the significantly lower rate of female patients undertaking heavy manual occupations compared to low-impact occupations (12.5% and 40.0%, respectively), data analysis was focused on male patients. Outcome variables were assessed for normality, and statistical comparisons were made between the heavy manual and low-impact groups using either an independent-samples t test or the Mann-Whitney U test. Results: Of 230 male patients, 98 were included in the heavy manual occupation group, and 132 were included in the low-impact occupation group. Patients in the heavy manual occupation group were significantly younger than those in the low-impact occupation group (mean age, 24.1 vs 25.9 years, respectively; P < .005). There was a greater range of active and passive knee flexion in the heavy manual occupation group than in the low-impact occupation group (mean active, 3.38° vs 5.33°, respectively [ P = .021]; mean passive, 2.76° vs 5.00°, respectively [ P = .005]). There was no difference in effusion, anterior knee laxity, limb symmetry index, IKDC score, return-to-sport rate, or graft rupture rate at 12 months. Conclusion: At 12 months after primary ACLR, male patients engaged in heavy manual occupations had a greater range of knee flexion, with no difference in the effusion rate or anterior knee laxity, compared with those engaged in low-impact occupations.

Background: The natural history of Kaplan fiber (KF) injuries after acute primary anterior cruciate ligament (ACL) reconstruction (ACLR) remains unknown. Purpose/Hypothesis: The purpose of this study was to evaluate the temporal change in the magnetic resonance imaging (MRI) appearance of the KF complex after acute primary ACLR. It was hypothesized that KF injuries would resolve with time. Study Design: Case series; Level of evidence, 4. Methods: A retrospective MRI analysis was conducted on 89 patients with ACL-injured knees to assess the change in the radiological appearance of KFs after primary ACLR. Patients who had undergone index MRI and ACLR within 90 days of the injury and further MRI at 9 months after surgery were included. Diagnostic criteria to identify radiological evidence of a KF injury and its subsequent resolution were applied, including the presence of high signal intensity on fluid-sensitive sequences, which is indicative of a pathological process radiologically. The proximity of KFs to the femoral cortical suspensory device (CSD) was noted on MRI scans and quantified in millimeters. Results: A KF injury was identified in 30.3% (27/89) of patients, with isolated high signal intensity observed in an additional 18.0% (16/89). At 9 months, MRI evidence of the reconstitution of the KF complex was found in 51.9% (14/27) of patients, with persistent discontinuity in the remaining patients (13/27). All patients (16/16) with isolated high signal intensity had complete resolution on repeat MRI scans. KF thickening was observed in 26.1% (12/46) of patients with previously healthy KFs and in 25.0% (4/16) with isolated high signal intensity. The CSD was positioned in close proximity (≤6 mm) to the center of the KF attachment in 61.8% (55/89) of patients, and this was associated with increased rates of KF thickening. Conclusion: The KF injury resolved radiologically in over half of the patients at 9 months after acute primary ACLR. High signal intensity in the region of the KFs on index MRI scans resolved in all cases, with evidence of residual KF thickening in only one-quarter of cases on repeat MRI scans, equivalent to the rate in those with healthy KFs. As such, it is not advisable to use high signal intensity on preoperative MRI scans as the sole criterion for the diagnosis of a KF injury. The position of the CSD after ACLR was intimately related to the KF attachment in the majority of patients, which was associated with KF thickening on postoperative MRI scans.