Primary Anterior Cruciate Ligament Rupture Research Articles

The effectiveness of quadrupled semitendinosus graft technique in anterior cruciate ligament reconstruction: A network meta-analysis assessing various graft preparation techniques.

This study aims to perform a network meta-analysis of hamstring graft preparation techniques to enhance anterior cruciate ligament (ACL) reconstruction guidelines and inform clinical decision-making in patients with primary ACL rupture. A review of the literature, from 1 January 1990, to 31 August 2023, was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, focusing on the clinical outcomes of various hamstring graft preparation techniques. Forty-six studies (over 4800 knees) were analysed. Eight graft compositions: doubled hamstring (ST/G)-1978 grafts, doubled hamstring with augmentation (ST/G+A)-586 grafts, tripled semitendinosus (3ST)-124 grafts, quadrupled semitendinosus (4ST)-1273 grafts, five-strand tripled semitendinosus + doubled gracilis (3ST/2GR-839 grafts, six-strand tripled semitendinosus + tripled gracilis (3ST/3GR)-335 grafts, seven-strand quadrupled semitendinosus + tripled gracilis (4ST/3GR)-11 grafts and ≥eight strands-24 grafts were compared, considering graft sizes, laxity, muscle strength, range-of-motion, patient-reported outcome measures (PROMs), return to sport (RTS) and adverse events. The 4ST grafts fared better than the ST/G grafts in the International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS) Sport, KOOS Q and RTS (mean difference [MD], -1.69; p = 0.0159; MD, -1.55; p = 0.0325; MD, -1.93; p = 0.001; odds ratio: 3.13; p < 0.0001). The IKDC differed significantly between the 4ST and ST/G+A groups (MD, 1.88; p = 0.046). The ST/G+A resulted in the lowest knee laxity, surpassing the ST/G, 3ST and 4ST. The ST/G had the smallest diameter (ST/G vs. ST/G+A: MD, 1.26; 95% confidence interval [CI]: 0.67-1.86, p < 0.0001). Reduced failure rates were noted with the 3ST/2GR (3ST/2GR vs. ST/G: MD, 6.93; p = 0.009) and 3ST/3GR (3ST/3GR vs. ST/G: MD, 53.64; p = 0.006). The ideal hamstring graft for ACLR should be individualized. A 4ST graft is likely to yield good PROMs. For high stability and rapid RTS, adding augmentation to the graft is advisable. The ST/G is the thinnest graft possible. Network meta-analysis of level I-III studies.

Tibiofemoral bone configuration is not associated with hamstring muscle strength in male and female patients with ACL reconstruction.

Previous evidence indicated that the tibiofemoral bone configuration might elevate the risk of an anterior cruciate ligament (ACL) injury. Furthermore, a low hamstring-to-quadriceps muscle ratio predisposes especially females to unfavourable knee kinematics. The primary objective of the present study was to investigate sex-specific associations between tibiofemoral bone geometry and isokinetic knee flexion torque in patients with primary ACL injury followed by ACL reconstruction. N = 100 patients (72 = male, 28 = female, age = 31.3 ± 10.2, body mass index = 25.3 ± 3.6) with primary ACL rupture with isokinetic knee flexion torque assessments before and 6 months after ACL reconstruction surgery were analysed. Magnetic resonance imaging scans were analysed for medial posterior tibial slope (MPTS) and lateral posterior tibial slope, notch width index (NWI) and lateral femoral condyle index (LFCI). Additionally, isokinetic knee flexion torque (60°/s) and hamstring-quadriceps ratios were evaluated. Subsequently, functional parameters were correlated with imaging data for gender subgroups. The findings showed that presurgical isokinetic knee flexion torque was not associated with any marker of femoral or tibial bone geometry. Further, while significant differences were observed between female (0.883 ± 0.31 Nm/kg) and male (1.18 ± 0.35 Nm/kg) patients regarding preoperative normalized knee flexion torque (p < 0.001), no significant sex differences were found for percentage increases in normalized knee flexion torque from presurgery to postsurgery. Generally, female patients demonstrated significantly higher MPTS magnitudes (p < 0.05) and lower LFCI values (p < 0.05) compared to men. The present results demonstrated no association between tibial or femoral bone geometry and muscle strength of the hamstrings in patients with ACL reconstruction, indicating an important mismatch of muscular compensation to deviations in bone geometry. There were no sex-specific differences in tibiofemoral bone parameters. Level III.

Comparison of Clinical Outcomes Between Modern Augmented ACL Repair and Autograft ACL Reconstruction: A Systematic Review and Meta-analysis of Studies With Minimum 2-Year Follow-up.

Anterior cruciate ligament (ACL) reconstruction has been the gold standard for primary ACL rupture since the 1990s. In the past decade, ACL repair has received renewed attention and increased research. To compare the clinical outcomes of modern augmented ACL repair versus autograft reconstruction for ACL ruptures. Systematic review; Level of evidence, 3. A search of the PubMed, EMBASE, Scopus, Web of Science, and the Cochrane Library databases was conducted for prospective or retrospective comparative studies published between January 1, 2010, and January 3, 2023, with a minimum 2-year follow-up. Two independent reviewers performed data extraction and methodological quality assessment. Sensitivity analysis was performed to maintain the stability of results. Nine studies were included (minimum follow-up period, 24-60 months). The total sample size was 833 patients (augmented repair group: 358 patients; autograft ACL reconstruction group: 475 patients). There were 4 randomized controlled trials (level 1), 1 prospective comparative study (level 2), 2 retrospective comparative studies (level 3), and 2 case-control studies (level 3). The augmented ACL repair group attained significantly higher Lysholm score (weighted mean difference [WMD] = 1.57; 95% confidence interval [CI], 0.14-3.01; P = .03) and hamstring strength (WMD = 36.69; 95% CI, 29.07-44.31; P < .01) but had higher rates of hardware removal (odds ratio [OR] = 6.30; 95% CI, 2.44-16.23; P = .0001), reoperation (OR = 1.87; 95% CI, 1.33-2.62; P = .0003), and failure (OR = 1.58; 95% CI, 1.03-2.43; P = .0003) compared with the autograft ACL reconstruction group. No significant differences were observed between the repair and reconstruction groups regarding postoperative International Knee Documentation Committee scores, Tegner scores, knee laxity, satisfaction, ACL revisions, complications, and reoperation rather than revision. Augmented ACL repair was associated with higher rates of reoperation, hardware removal, and failure compared with autograft ACL reconstruction in studies with minimum 2-year follow-up data. However, augmented ACL repair had higher Lysholm scores and hamstring strength versus autograft ACL reconstruction.

Acute effects of ipsilateral semitendinosus and gracilis autograft anterior cruciate ligament reconstruction on lower limb muscle activation

There is little information regarding the acute repercussions of anterior cruciate ligament (ACL) reconstruction on muscle activation, especially on the proximal hip muscles. Thus, this study analyzed the acute effects of ACL reconstruction with doubled semitendinosus/gracilis (ST/G) autografts on lower limb muscle activation. Fourteen male recreational athletes that presented a primary unilateral ACL rupture and underwent the ACL reconstruction with an ST/G graft. Surface electromyographic (sEMG) signal were recorded from each participant during the maximal voluntary isometric contraction (MVIC) of the gluteus maximus and gluteus medius, vastus lateralis and vastus medialis, semitendinosus, biceps femoris, and medial gastrocnemius muscles and also during bipodal mini-squatting with open and closed eyes, before surgery and 15 days postoperatively. (sEMG) signal were normalized to isometric peak electromyography.The postoperative assessment showed reduced muscle activation in the gluteus maximus (p = 0.013, d:0.48) in non-operated limb and also in the muscle gluteus medius (p = 0.013, d:0.79), vastus medialis (p = 0.035, d:0.63) semitendinosus (p = 0.001, d:2.46), biceps femoris (p<0.001, d:1.5), and medial gastrocnemius (p = 0.001, d:1.45) during MVIC in the operated limb. The postoperative assessment also revealed alterations in the sEMG activity of the hip and local thigh muscles in the operated and non-operated limbs during mini-squatting with opened eyes and closed eyes (p<0.05). ACL reconstruction surgery with a doubled ST/G autograft may promote immediate changes in lower limb muscle activation of the operated and non-operated limb.

Effectiveness of anterior cruciate ligament reconstruction with personalized femoral locator based on apex of deep cartilage

To investigate the effectiveness of anterior cruciate ligament (ACL) reconstruction assisted by personalized femoral locator based on the apex of deep cartilage (ADC) combined with patient imaging data. Between January 2021 and January 2022, a total of 40 patients with primary ACL rupture were selected and randomly divided into study group (ACL reconstruction assisted by personalized femoral locator based on ADC) and control group (ACL reconstruction assisted by intraoperative fluoroscopy and traditional femoral locator), with 20 cases in each group. There was no significant difference in gender, age, body mass index, affected side, cause of injury, and preoperative International Knee Documentation Committee (IKDC) score, Lyshlom score, and Tegner score between the two groups ( P>0.05). IKDC score, Lyshlom score, and Tegner score were used to evaluate the functional recovery of the affected knee before operation and at 3, 6, and 12 months after operation. CT scan and three-dimensional reconstruction were performed before and after operation to measure the horizontal distance from ADC to the anterior cartilage margin (L) and the horizontal distance from ADC to the center of the femoral canal (I), and the anteroposterior position of the bone canal (R) was calculated by I/L; the distance from the center to the distal cartilage margin (D) was measured on the two-dimensional cross section; the R value and D value were compared between the two groups. The operation time of the study group was significantly less than that of the control group [ MD=-6.90 (-8.78, -5.03), P<0.001]. The incisions of the two groups healed by first intention, and no complication such as intra-articular infection, nerve injury, and deep vein thrombosis of lower limbs occurred. There was no significant difference in the R value and D value between the preoperative simulated positioning and the actual intraoperative positioning in the study group [ MD=0.52 (-2.85, 3.88), P=0.758; MD=0.36 (-0.39, 1.11), P=0.351]. There was no significant difference in the actual intraoperative positioning R value and D value between the study group and the control group [ MD=1.01 (-2.57, 4.58), P=0.573; MD=0.24 (-0.34, 0.82), P=0.411]. The patients in both groups were followed up 12-13 months (mean, 12.4 months). The IKDC score, Lysholm score, and Tegner score of the two groups increased gradually with time, and there were significant differences between pre- and post-operation ( P<0.05). There was no significant difference in the scores between the two groups at each time point after operation ( P>0.05). The personalized femoral locator based on ADC can accurately assist the femoral tunnel positioning in ACL reconstruction, which can shorten the operation time when compared with traditional surgical methods, and achieve satisfactory early effectiveness.

Evidence of Bacterial Metabolism in Synovial Fluid of Patients With Graft Failure After Anterior Cruciate Ligament Reconstruction: A Microbiological Comparison of Primary Anterior Cruciate Ligament and Hamstring Tendon Autograft Ruptures

To investigate whether the bacterial presence in a primary ruptured native anterior cruciate ligament (ACL) differs from that in a ruptured hamstrings ACL autograft and whether low-grade infections cumulatively can be detected in the case of graft failure. In a retrospective case-control study with prospectively collected data, synovial fluid aspirates and tissue samples of failed ACL grafts were examined for evidence of bacterial colonization and compared to samples of the native ACL in primary ACL reconstruction (ACLR) using microbiological culture, 16S rRNA-PCR and histopathological examination. Furthermore, synovial fluid aspiration was investigated for possible future biomarkers for a low-grade infection. A total of 112 consecutive patients undergoing primary ACLR without history of previous surgeries to the affected knee (n= 59) and revision ACLR after reconstruction with a hamstring tendon autograft (n= 53) were recruited from one center. No patient had a history or showed clinical signs of infection. A total of 389 samples were analyzed by culture. Bacteria were detected in 9.4% of patients with a graft rupture (n= 5/53) compared to 3.4% of patients with a primary ACL rupture (n= 2/59) showing no statistical difference (P= .192). One patient with a "true" low-grade infection was found in our study population, resulting in a prevalence of 1.9% (1/53) in the graft group. The percentage of polymorphonuclear leukocytes (PMN%) as a highly sensitive marker for joint infections was significantly higher in aspirated synovial fluid of graft ruptures (27% ± 3% vs 20% ± 4%; P= .032), as well as glucose levels were significantly lower (83 mg/dL ± 2 mg/dL vs 88 mg/dL ± 2 mg/dL; P= .042). Synovial fluid obtained before revision ACLR showed a higher percentage of polymorphonuclear leukocytes and lower glucose levels compared with primary ACLR, suggesting bacterial metabolism and demonstrating that the intra-articular milieu changes significantly after ACLR. Tissue samples of ACL grafts revealed a low-grade infection in one case, although overall cultivable bacterial presence did not differ significantly when compared to samples of a native ACL. Level III, retrospective case-control study.

Brace-Free Rehabilitation after Isolated Anterior Cruciate Ligament Reconstruction with Hamstring Tendon Autograft Is Not Inferior to Brace-Based Rehabilitation-A Randomised Controlled Trial.

The postoperative use of a rehabilitative knee brace after isolated primary anterior cruciate ligament (ACL) reconstruction (ACLR) using a hamstring tendon (HT) autograft is controversial. A knee brace may provide subjective safety but can cause damage if applied incorrectly. The aim of this study is to evaluate the effect of a knee brace on clinical outcomes following isolated ACLR using HT autograft. In this prospective randomised trial, 114 adults (32.4 ± 11.5 years, 35.1% women) underwent isolated ACLR using HT autograft after primary ACL rupture. Patients were randomly assigned to wear either a knee brace (n = 58) or no brace (n = 56) for 6 weeks postoperatively. An initial examination was performed preoperatively, and at 6 weeks and 4, 6, and 12 months. The primary endpoint was the subjective International Knee Documentation Committee (IKDC) score to measure participants' subjective perceptions. Secondary endpoints included objective knee function assessed by IKDC, instrumented knee laxity measurements, isokinetic strength tests of the knee extensors and flexors, Lysholm Knee Score, Tegner Activity Score, Anterior Cruciate Ligament-Return to Sport after Injury Score, and quality of life determined by Short Form-36 (SF36). There were no statistically significant or clinically meaningful differences in IKDC scores between the two study groups (3.29, 95% confidence interval (CI) -1.39 to 7.97, p = 0.03 for evidence of non-inferiority of brace-free compared with brace-based rehabilitation). The difference in Lysholm score was 3.20 (95% CI -2.47 to 8.87); the difference in SF36 physical component score 0.09 (95% CI -1.93 to 3.03). In addition, isokinetic testing did not reveal any clinically relevant differences between the groups (n.s.). Brace-free rehabilitation is non-inferior to a brace-based protocol regarding physical recovery 1 year after isolated ACLR using HT autograft. Consequently, the use of a knee brace might be avoided after such a procedure. Level I, therapeutic study.

Knee osteoarthritis, joint laxity and PROMs following conservative management versus surgical reconstruction for ACL rupture: a meta-analysis.

Patients whose rupture of the anterior cruciate ligament (ACL) can be managed conservatively or undergo reconstruction surgery. Current scientific literature published in Web of Science, PubMed and Scopus. Several studies published by July 2022 compare surgical and conservative management following ACL rupture. The latest evidence suggests that surgical management may expose patients to an increased risk of early-onset knee osteoarthritis (OA). The state of art does not recommend a systematic ACL reconstruction to all patients who tore their ACL. After the initial trauma, surgical reconstruction may produce even greater damage to the intra-articular structures compared to conservative management. The state of art does not recommend systematic surgical reconstruction to all patients who tore their ACL. The present study compared surgical reconstruction versus conservative management for primary ACL ruptures in terms of joint laxity, patient reported outcome measures (PROMs) and rate of osteoarthritis. ACL reconstruction provides significant improvement in joint laxity compared to conservative management, but is associated with a significantly greater rate of knee osteoarthritis, despite similar results at PROM assessment.

Anatomic Factors Associated With the Development of an Anterior Cruciate Ligament Rerupture in Men: A Case-Control Study

Background: Although several factors are associated with anterior cruciate ligament (ACL) rerupture, the effect of anatomic factors associated with ACL rupture on ACL rerupture development has not been evaluated. Purpose: To determine individual anatomic parameters independently associated with ACL rerupture and the diagnostic values of these parameters. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 91 male patients with ACL rerupture and 182 age-, sex-, body mass index–, and side dominance–matched patients without rerupture who underwent ACL reconstruction with a 5-year follow-up were included. In all, 35 parameters that were previously defined as risk factors for primary ACL rupture were compared between the 2 groups. Uni- and multivariate logistic regression models were created to evaluate independently associated factors. Receiver operating characteristic curve analysis was performed for independently associated parameters to predict sensitivity, specificity, and cutoff values. Results: The mean ± standard deviation age of patients at the time of index surgery was 26.5 ± 6.7 years. Notch shape index (P = .014), tibial proximal anteroposterior (AP) distance (TPAPD) (P < .001), lateral femoral condylar AP distance (LCAPD)/TPAPD ratio (P < .001), medial meniscal cartilage bone height (P < .001), and lateral meniscal bone angle (P = .004) were found to be significantly different between the 2 groups. Only the LCAPD/TPAPD ratio (odds ratio, 2.713; 95% CI, 1.998-5.480; P < .001) was found to be independently associated with ACL rerupture development. The LCAPD/TPAPD ratio revealed 78.9% sensitivity and 75.5% specificity (area under the curve, 0.815; 95% CI, 0.760-0.870) for values above 1.52. Conclusion: The LCAPD/TPAPD ratio can be used to distinguish patients who are at risk of developing ACL rerupture from patients who are not. In the clinical practice, findings of this study may help to develop surgical and nonsurgical preventive strategies in ACL rerupture development.

Pre-operative knee extensor and flexor torque after secondary ACL rupture: a comparative retrospective analysis

BackgroundSecondary anterior cruciate ligament (ACL) ruptures are a relevant clinical concern after surgical treatment of a primary ACL rupture. However, there is a lack of scientific evidence related to the role of muscle strength prior to revision surgery in a second ACL rupture. The aim of this study was to assess differences in knee extensor and flexor strength in patients before primary and secondary ACL reconstruction compared to healthy controls.MethodsIn total, n = 69 age, weight and sex matched individuals were included in the study: n = 23 patients with isolated primary ACL rupture, n = 23 with secondary ACL rupture, and n = 23 matched healthy controls. Maximal isokinetic knee extension and flexion torque normalized to body mass was assessed for both legs.ResultsFor patients with secondary ACL ruptures, torques were reduced in the non-injured (extension: 1.94 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.25 Nm/kg vs. 1.59 Nm/kg, p < 0.05) and the injured leg (extension: 1.70 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.14 Nm/kg vs. 1.59 Nm/kg, p < 0.05) compared to healthy controls. For patients with a primary ACL rupture torques were reduced in the non-injured (extension: 1.92 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.24 Nm/kg vs. 1.59 Nm/kg, p < 0.05) and the injured leg (extension: 1.38 Nm/kg vs. 2.46 Nm/kg, p < 0.05, flexion: 1.01 Nm/kg vs. 1.59 Nm/kg, p < 0.05) compared to healthy controls. There were no differences between patients with primary and secondary ruptures, except of the knee extension on the injured leg showing higher values after a secondary ACL rupture (1.38 Nm/kg vs. 1.70 Nm/kg, p < 0.05).ConclusionsThe findings indicate that maximal knee torques were significantly reduced in patients with primary and secondary ACL ruptures before surgical reconstruction for the non-injured and injured leg as compared to healthy controls. Further investigations are needed to assess strength abilities before and after a second revision within a prospective design.

The Relationship Between Lateral Femoral Condyle Index and Noncontact Anterior Cruciate Ligament Rupture.

PurposeThe purpose of this study was to examine the relationship between distal femoral morphology and noncontact anterior cruciate ligament (ACL) rupture and the differences between digital X-ray imaging systems (DR) and magnetic resonance imaging (MRI) to evaluate distal femoral morphology.MethodsA retrospective case-control study was performed on 120 patients. Two age- and sex-matched cohorts (each n = 60) were analyzed: primary ACL ruptures and a control group consisting of isolated meniscal tears. The lateral femoral condyle index (LFCI) was measured by DR and by MRI to quantify femoral sphericity. Differences among two groups were compared, and diagnostic performance of the risk factors was assessed. In addition, differences between DR and MRI to evaluate LFCI were examined.ResultsThe LFCI by MRI was smaller in the knees with primary ACL rupture (median, 0.71; range, 0.62–0.78) than that of the control group (median, 0.77; range, 0.66–0.85) (p < 0.01). The LFCI was also significantly smaller in the knees with primary ACL rupture (median, 0.72; range, 0.63–0.77) than that of the control group (median, 0.79; range, 0.65–0.84) (p < 0.01) by DR. A cutoff of 0.74 of MRI yielded a sensitivity of 77% and a specificity of 78% to predict an ACL rupture, and of 0.75 of DR yield a sensitivity of 87% and a specificity of 77% to predict an ACL rupture.ConclusionThis study showed that a decreased LFCI is associated with an ACL rupture, and both DR and MRI measurements can effectively predict the risk of ACL rupture. This helps expand the scope of the application of the LFCI and helps clinicians identify susceptible individuals who may benefit from targeted ACL rupture prevention counseling and intervention.

Individual and Combined Anatomic Risk Factors for the Development of an Anterior Cruciate Ligament Rupture in Men: A Multiple Factor Analysis Case-Control Study

Background: No comparative studies have evaluated anatomic risk factors in a large cohort including both patients with anterior cruciate ligament (ACL) ruptures and healthy participants. Purpose: To determine which anatomic parameters are independently associated with an ACL rupture and the diagnostic values of the individual and combined anatomic parameters. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 352 male patients who underwent arthroscopic ACL reconstruction because of a primary ACL rupture and 350 age-, sex-, body mass index–, and side dominance–matched healthy participants were included. Measurements of 32 previously determined parameters and 7 calculations were performed. Between-group differences were calculated. Univariate and multivariate logistic regression models and receiver operating characteristic curve analysis were conducted for the individual and combined independently associated factors. Results: The mean age and body mass index of all participants were 29.9 ± 7.7 years and 27.2 ± 3.1, respectively. There were significant differences between the groups regarding the notch width (NW), notch shape index, anterior tibial slope, notch width index, NW–eminence width (NW:EW) ratio, notch height, axial lateral wall angle, medial intercondylar ridge thickness, alpha angle, medial tibial depth (MTD), lateral tibial slope (LTS), coronal tibial plateau width, eminence width index, tibial proximal anteroposterior distance (TPAP), lateral condylar anteroposterior distance (LCAP)/TPAP, ACL cross-sectional area, ACL volume, medial and lateral meniscal cartilage height, medial and lateral meniscal cartilage angle (MCA), and medial and lateral meniscal cartilage bone height. The NW:EW ratio (odds ratio [OR], 4.419; P = .017), MTD (OR, 8.617; P = .001), LTS (OR, 2.254; P = .011), LCAP/TPAP (OR, 2.782; P = .037), and medial MCA (OR, 1.318; P = .010) were independently associated with the development of an ACL rupture. Combining the independently associated factors revealed a sensitivity of 93% and a specificity of 94% (area under the curve, 0.968). Conclusion: Patients with ACL ruptures could be distinguished from uninjured controls with high sensitivity and specificity via the combined use of the NW:EW ratio, MTD, LTS, LCAP/TPAP, and medial MCA. In clinical practice, these findings may contribute to the development of preventive strategies for ACL ruptures.

Tibiofemoral Relationship 3 Weeks After Anatomic Triple-Bundle Anterior Cruciate Ligament Reconstruction With 10 N of Initial Tension Is Closer to Normal Knee Versus That With 20 N of Initial Tension

PurposeThis study aimed to clarify the effect of initial graft tension on the ensuing tibiofemoral relationship and on 2-year clinical outcomes after anatomic triple-bundle anterior cruciate ligament (ACL) reconstruction. MethodsA total of 31 patients with primary unilateral ACL rupture (mean age, 25.1 years) were enrolled. Anatomic triple-bundle ACL reconstruction was performed using semitendinosus tendon autografts, and patients were grouped according to the total initial tension at graft fixation: 20 N for 16 patients between January 2012 and December 2012 and 10 N for 15 patients between January 2013 and December 2013. Three-dimensional computed tomography scans were performed preoperatively and at 3 weeks and 6 months postoperatively. The side-to-side difference of the 3-dimensional tibial position relative to the femur was compared at each time point. The side-to-side difference in anterior laxity was sequentially compared preoperatively, immediately after surgery, and at 6 months and 2 years postoperatively. Clinical outcomes at 2 years were likewise compared. ResultsOne patient in each group was excluded because of secondary ACL injury. At 3 weeks postoperatively, 2.5 ± 1.3 and 1.0 ± 1.3 mm of posterior tibial displacement and 3.8° ± 2.4° and 2.0° ± 1.7° of external rotation were observed in the 20- and 10-N initial tension groups, respectively, with significant differences (P = .006 and .033). At 6 months postoperatively, anterior displacement was 0.1/0.1 mm and external rotation was 0.8°/0.4° in both groups, without any significant differences. The 2-year clinical outcomes were satisfactory, including mean side-to-side difference in anterior knee laxity of 0.5 mm in both groups. ConclusionThe tibiofemoral relationship 3 weeks after anatomic triple-bundle ACL reconstruction with 10 N of initial tension is less constrained than that with 20 N. Six-month tibiofemoral relationship and 2-year clinical outcomes are satisfactory in both groups. Level of EvidenceIII, retrospective comparative trial

Laxity measurement of internal knee rotation after primary anterior cruciate ligament rupture versus rerupture

PurposeThe aim of the current study was to objectify the rotational laxity after primary anterior cruciate ligament (ACL) rupture and rerupture after ACL reconstruction by instrumented measurement. It was hypothesized that knees with recurrent instability feature a higher internal rotation laxity as compared to knees with a primary rupture of the native ACL.Study designCross-sectional study, Level of evidence III.MethodsIn a clinical cross-sectional study successive patients with primary ACL rupture and rerupture after ACL reconstruction were evaluated clinically and by instrumented measurement of the rotational and antero-posterior laxity with a validated instrument and the KT1000®, respectively. Clinical examination comprised IKDC 2000 forms, Lysholm Score, and Tegner Activity Scale. Power calculation and statistical analysis were performed (p value < 0.05).Results24 patients with primary ACL rupture and 23 patients with ACL rerupture were included. There was no significant side-to-side difference in anterior translation. A side-to side difference of internal rotational laxity ≥ 10° was found significantly more frequent in reruptures (53.6%) compared to primary ruptures (19.4%; p < 0.001). A highly significant relationship between the extent of the pivot-shift phenomenon and side-to-side difference of internal rotation laxity could be demonstrated (p < 0.001). IKDC 2000 subjective revealed significantly better scores in patients with primary ACL tear compared to patients with ACL rerupture (56.4 ± 7.8 vs. 50.8 ± 6.2; p = 0.01). Patients with primary ACL tears scored significantly better on the Tegner Activity Scale (p = 0.02). No significant differences were seen in the Lysholm Score (p = 0.78).ConclusionPatients with ACL rerupture feature significantly higher internal rotation laxity of the knee compared to primary ACL rupture. The extend of rotational laxity can be quantified by instrumented measurements. This can be valuable data for the indication of an anterolateral ligament reconstruction in ACL revision surgery.

Knee Malignment: Is There a Role for Correction in Primary ACLR?

Sagittal and coronal knee alignment impacts the biomechanics of the surrounding ligamentous structures, including the anterior cruciate ligament (ACL). Biomechanical studies have shown that increased degrees of varus alignment (>3°-5°) and increased amount of posterior tibial slope (>12°) significantly increase the force on the native ACL. Malalignment in the coronal and sagittal planes have been implicated as primary contributing factors in graft failure following ACL reconstruction. Clinical series have demonstrated encouraging results following either valgus-producing or slope-reducing proximal tibial osteotomy, although largely in the setting of revision ACL reconstruction, with lower rates of graft failure and improved patient-reported outcomes. However, few studies have reported on the success of osteotomy in the setting of a primary ACL rupture.

Clinical and radiological outcome after anterior cruciate ligament reconstruction using the T-lock Osteotrans resorbable tendon anchor: early experience and midterm follow-up

PurposeReconstruction of the Anterior cruciate ligament (ACL) using tendon grafting is an established method for restoring knee function and stability. Multiple methods are established for graft fixation. Several involve anchoring the autograft distant to the joint with hardware that remains implanted. This study reports the first early to midterm results in patients who received ACL reconstruction (ACLR) using the T-Lock Osteotrans femoral near joint fixation method with a tibial fixation using the BioactIF Osteotrans interference screw.MethodsThis consecutive prospective series included 20 Patients (14 Male, 6 Female) with a primary ACL rupture. All patients were treated with an ACLR using a semitendinosus autograft fixated with the T-Lock Osteotrans and were followed-up postoperatively. The following parameters were assessed: Side-to-side difference of the posterior-anterior translation measured using the KT-1000 arthrometer, Tegner activity score, Lysholm score, IKDC subjective knee evaluation form. Magnetic resonance imaging (MRI) was done to assess tunnel enlargement and integrity of the anchoring device.ResultsThe average follow-up duration was 2 years (range 1–4.2 years). One patient was lost to follow-up. Two Patients suffered a traumatic ACL re-rupture 2 years postoperatively and received a 2-stage revision ACLR. Difference in the posterior-anterior translation was 1.8 mm (range 0–5). The median Tegner score was 6 (range 4–10) and 9 patients (45%) returned to their preinjury level of activity. The mean IKDC subjective knee evaluation form scored 91 points (range 77–100). The mean Lysholm score was 86 points (74–96). All mentioned scores were significantly better compared to preoperative values. No relevant tunnel enlargement was seen on MRI. The anchoring device was evaluated to be intact in all patients.ConclusionACLR with the aforementioned procedure leads to good clinical and radiological outcome.

Matrix Metalloproteinase Genes (MMP1, MMP10, MMP12) on Chromosome 11q22 and the Risk of Non-Contact Anterior Cruciate Ligament Ruptures.

Background: Sequence variants within the matrix metalloproteinases genes remain plausible biological candidates for further investigation of anterior cruciate ligament (ACL) rupture risk. The aim of the present study was to establish whether variants within the MMP1 (rs1799750, ->G), MMP10 (rs486055, C > T) and MMP12 (rs2276109, T > C) genes were associated with non-contact ACL rupture in a Polish cohort. Methods: The unrelated, self-reported Polish Caucasian participants consisted of 228 (157 male) individuals with primary non-contact ACL rupture and 202 (117 male) participants without any history of ACL rupture. All samples were genotyped in duplicate using the Applied Biosystems TaqMan® methodology. The statistical analyses were involved in determining the distribution of genotype and allele frequencies for the investigated polymorphisms between the diagnostic groups. Furthermore, pseudo-haplotypes were constructed to assess possible gene–gene interactions. Results: All genotype frequencies in the ACL rupture and control groups conformed to Hardy Weinberg Equilibrium expectations. None of the polymorphisms were associated with risk of non-contact ACL rupture under the codominant, dominant, recessive and over-dominant genetic models. Likewise, no genotype–genotype combinations inferred as “haplotypes” as a proxy of gene–gene interactions were associated with the risk of non-contact ACL ruptures. Conclusions: Despite the fact that the current study did not support existing evidence suggesting that variants within the MMP1, MMP10, and MMP12 genes influence non-contact ACL rupture risk, future work should include high-throughput sequencing technologies to identify potential targeted polymorphisms to fully characterize the 11q22 region with susceptibility to non-contact ACL rupture susceptibility in a Polish cohort.

Baseline Analysis of Patients Presenting for Surgical Review of Anterior Cruciate Ligament Rupture Reveals Heterogeneity in Patient-Reported Outcome Measures.

Despite the establishment of successful surgical techniques and rehabilitation protocols for anterior cruciate ligament (ACL) reconstruction, published return to sport rates are less than satisfactory. This has led orthopaedic surgeons and researchers to develop more robust patient selection methods, and investigate prognostic patient characteristics. No previous studies have integrated baseline characteristics and responses to patient-reported outcome measures (PROMs) of patients with ACL rupture presenting for surgical review. Patients electing to undergo ACL reconstruction under the care of a single orthopaedic surgeon at a metropolitan public hospital were enrolled in a clinical quality registry. Patients completed Veterans RAND 12-item Health Survey (VR-12) Physical Component Summary and Mental Component Summary scores, Tegner activity scale, and International Knee Documentation Committee (IKDC) questionnaires at presentation. Total scores were extracted from the electronic registry, and a machine learning approach (k-means) was used to identify subgroups based on similarity of questionnaire responses. The average scores in each cluster were compared using analysis of variance (ANOVA; Kruskal-Wallis) and nominal logistic regression was performed to determine relationships between cluster membership and patient age, gender, body mass index (BMI), and injury-to-examination delay. A sample of 107 patients with primary ACL rupture were extracted, with 97 (91%) available for analysis with complete datasets. Four clusters were identified with distinct patterns of PROMs responses. These ranged from lowest (Cluster 1) to highest scores for VR-12 and IKDC (Cluster 4). In particular, Cluster 4 returned median scores within 6 points of the patient acceptable symptom state for the IKDC score for ACL reconstruction (70.1, interquartile range: 59-78). Significant (p < 0.05) differences in PROMs between clusters were observed using ANOVA, with variance explained ranging from 40 to 69%. However, cluster membership was not significantly associated with patient age, gender, BMI, or injury-to-examination delay. Patients electing to undergo ACL reconstruction do not conform to a homogenous group but represent a spectrum of knee function, general physical and mental health, and preinjury activity levels, which may not lend itself to uniform treatment and rehabilitation protocols. The factors driving these distinct responses to PROMs remain unknown but are unrelated to common demographic variables.

A decreased ratio of height of lateral femoral condyle to anteroposterior diameter is a risk factor for anterior cruciate ligament rupture

BackgroundStudies have shown that the spherical shape of the lateral femoral condyle has a clear relationship with the relative axial movement of tibiofemoral joint and the anterior cruciate ligament (ACL) rupture. The purpose of this study was to describe the distal curvature of the lateral femoral condyle by ratio of height of lateral femoral condyle to anteroposterior diameter (HAPR), and evaluate its correlation with ACL rupture.MethodsA retrospective case-control study of 64 patients was conducted. Two age-and sex-matched cohorts (each n = 32) were analyzed: primary ACL ruptures, and a control group consisting of isolated meniscal tears. On the radiograph, the distance from the intersection of the axis of the distal femur and the anteriorly diameter of the lateral femoral condyle to the lower point of the lateral femoral condyle divided by the anteriorly diameter of the lateral femoral condyle is HAPR. The HAPR was measured by digital radiograph imaging systems (DR) to quantify femoral sphericity. Cutoff values were defined; and diagnostic performance of the risk factors was assessed. Meanwhile, we measured the posterior tibial slope (PTS) on radiograph and compared the two methods to evaluate the significance of HAPR in predicting ACL rupture.ResultsA total of sixty-four patients who met the inclusion criteria were included in the final analysis (32 with primary ACL rupture, 32 controls). The HAPR was smaller in the knees with primary ACL rupture (0.31 ± 0.02) than that of the control group (0.33 ± 0.02) (p < 0.01). The PTS was bigger in the knees with primary ACL rupture (8.18 ± 2.77) than that of the control group (6.61 ± 2.85) (p = 0.036). The AUC of HAPR was bigger (0.825; 95% CI, 0.72–0.93) than that of PTS (0.675; 95%CI, 0.85–0.81). The calculated cutoff of HAPR of 0.32 (Youden index, 0.56) was associated with an increased risk for ACL rupture, with sensitivity of 75% and specificity of 81% to predict an ACL rupture.ConclusionsThis study showed that a decreased HAPR is associated with an ACL rupture, and the decrease of HAPR was more significant in predicting ACL ruptures than the PTS. This helps clinicians identify susceptible individuals who may benefit from targeted ACL rupture prevention counseling and intervention.

Quadriceps tendon vs. patellar tendon autograft for ACL reconstruction using a hardware-free press-fit fixation technique: comparable stability, function and return-to-sport level but less donor site morbidity in athletes after 10\xa0years

IntroductionThe use of quadriceps tendon–patellar bone (QTB) autograft for anterior cruciate ligament (ACL) reconstruction is gaining momentum. Yet, long-term results that compare this procedure with established methods are lacking. The aim of this study was to report and compare long-term results of ACL reconstruction using QTB autografts versus bone–patellar tendon–bone (BPTB) autografts, both anchored using a hardware-free press-fit fixation technique.Materials and methods60 athletes (Tegner score ≥6) with primary ACL rupture were prospectively randomized into two groups. 56 patients were evaluated after a mean duration of 12.2 ± 1.9 months (range 10–14) and 43 patients after 10.3 ± 0.2 years (range 10–11).ResultsOn final follow-up, 90% of patients scored very good and good results in the functional Lysholm score (mean 99 ± 7.1, range 74–100 points). Normal or almost normal IKDC score was reported by 84% of the patients (mean 97 ± 9.5, range 60–100 points). The activity level decreased in the Tegner score from median of 7 before injury to 6 after 10 years. The KT-1000 arthrometer showed a difference in the anterior translation of less than 3 mm (mean 1.0 ± 1.2, range − 1 to 5 mm) in 91% of the patients. Significant degeneration was radiologically detected in one patient per group. No tunnel widening was seen in any patient. Up to 97% of all patients were satisfied with the operative procedure. No significant differences were found in the mentioned parameters between the two groups and also in comparison with the 1-year results. The only significant difference was in the donor site morbidity. Significantly more patients in the BPTB group had complaints during kneeling both at 1 (p < 0.001) and 10 years (p = 0.019). Squatting was also subjectively more problematic in the BPTB group than in the QTB group both after 1 (p = 0.003) and 10 years (p = 0.046).ConclusionsThis study shows equally good functional, clinical and radiological long-term results for both hardware-free methods of ACL reconstruction. These results clinically confirm the safety of press-fit anchoring after 10 years. The failure rate in this study was very low, with only one re-rupture in 10 years. The increased donor site morbidity when using the BPTB autograft compared to the QTB autograft supports already reported data. It was also seen in this study for the implant-free press-fit techniques.Study designProspective and randomized, level of evidence 2.