Contralateral Anterior Cruciate Ligament Injury Research Articles

Re-injuries and Contralateral ACL Injuries after ACL Reconstruction in Professional Sumo Wrestlers

Re-injuries and Contralateral ACL Injuries after ACL Reconstruction in Professional Sumo Wrestlers

An Increased Lateral Femoral Condyle Ratio Is a Risk Factor for Anterior Cruciate Ligament Injury.

The purpose of this study was to examine the relationship between distal femoral morphology and anterior cruciate ligament (ACL) injury, ACL reconstruction (ACLR) failure, and contralateral ACL injury. It was hypothesized that increased posterior femoral condylar depth, quantified as the lateral femoral condyle ratio, would correlate with increased risk of primary ACL injuries, ACLR failures, and contralateral ACL injuries. The charts of consecutive patients who underwent arthroscopic knee surgery at an academic medical center from 2012 to 2016 with minimum follow-up of 24 months were retrospectively reviewed. Patients were stratified into 4 groups: (1) a control group of patients with no ACL injury, (2) patients with primary ACL injury, (3) patients with failed ACLR, and (4) patients with previous ACL injury and subsequent contralateral ACL injury. With use of lateral radiographs, the ratio of posterior femoral condylar depth to total condylar length was defined as the lateral femoral condyle ratio. Differences between study groups were identified with use of analysis-of-variance (ANOVA) and post-hoc testing with significance set at p < 0.05. Receiver operating characteristic (ROC) curve analysis was performed to determine the optimal cutoff for detecting increased risk of ACL injury. Two hundred patients met the inclusion criteria. The mean lateral femoral condyle ratios (and standard deviations) were 61.2% ± 2.4% in the control group, 64.2% ± 3.8% in the primary ACL injury group, 64.4% ± 3.6% in the failed ACLR group, and 66.9% ± 4.3% in the contralateral ACL injury group. Patients who had a primary ACL injury, failed ACLR, or contralateral ACL injury had significantly higher ratios compared with the control group (p < 0.008). ROC curve analysis demonstrated that a lateral femoral condyle ratio of >63% was associated with an increased risk for ACL injury, with a sensitivity of 77% and a specificity of 72%. The data from this study show that increased posterior femoral condylar depth, quantified as the lateral femoral condyle ratio, is associated with an increased risk of ACL injury, including primary and contralateral ACL injuries. The data from this study may help clinicians to identify patients at a greater risk of ACL injury. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Tomahawk Shaped Femur is a Risk Factor for Anterior Cruciate Ligament Injury

Aims and Objectives: Bony morphologic characteristics have been demonstrated to increase the risk of anterior cruciate ligament (ACL) injury. The purpose of the study was to examine distal femoral morphology relative to ACL injury, reconstruction failure, and contralateral ACL injury.It was hypothesized that an increased posterior femoral condylar depth, quantified as the tomahawk ratio, would correlate with increased risk of primary ACL ruptures, ACL reconstruction failures, and contralateral ACL injuries. Materials and Methods: Consecutive patients undergoing arthroscopic knee surgery at an academic medical center from 2012-2016 with minimum 24-month follow-up were retrospectively reviewed. Subjects were stratified into four groups: a control group consisting of patients with no ACL injuries and three groups of patients with a primary ACL injury, failed ACL reconstruction, or previous ACL injury with subsequent contralateral ACL injury. Using lateral radiographs, the ratio of posterior condylar depth over total condylar distance was defined as the tomahawk ratio. Analysis-of-variance (ANOVA) and post-hoc testing were used to test for differences in the mean tomahawk ratio between study groups (p<0.05). Receiver Operating Characteristic (ROC) analysis was performed to determine the optimal tomahawk ratio cut-off for detecting increased risk for ACL injury Results: 175 patients met inclusion criteria. The mean tomahawk ratios in the control group, primary ACL injury group, failed ACL reconstruction group, and contralateral ACL injury group were 61.1% (± 2.1), 64.2% (± 3.8), 64.4% (± 3.6), and 66.9% (± 4.0), respectively. Patients with a primary ACL injury, failed ACL reconstruction, or contralateral ACL injury had a significantly higher tomahawk ratio compared to the control group (p<0.008). ROC analysis demonstrated a tomahawk ratio of 63% or greater to be associated with an increased risk for ACL injury with a sensitivity of 83% and a specificity of 71%. Conclusion: The data from this study show that an increased posterior femoral condylar depth, or tomahawk ratio, is associated with increased risk of ACL injury, including primary ACL injury, failed ACL reconstruction, and contralateral ACL injury. Readily identifiable risk factors, such as an increased tomahawk ratio, could assist clinicians in identifying at-risk individuals who may experience greater benefit from targeted ACL injury prevention counseling and intervention. The presence of the tomahawk-shaped femur could also be used to guide treatment decisions and identify ACL reconstruction patients who may benefit from additional surgical procedures such as extra articular tenodesis.

Revision ACL Reconstruction in Children and Adolescents.

Revision anterior cruciate ligament (ACL) reconstruction in pediatric patients has not been well studied. The purpose of this study was to assess the demographics, technique, and results of ACL revision surgery in children and adolescents. This was a retrospective case series with outcomes assessment of patients 18 years old and younger who underwent revision ACL surgery over a 16-year period at a single institution. Medical records were reviewed for demographics, clinical and operative data, and patients were contacted for outcomes at a minimum of 1 year after revision surgery. Ninety revision ACL reconstructions were performed by 7 surgeons in 88 patients (44 male, 44 female). Average patient age at the time of revision was 16.6 years (SD, 1.7), and 28.8% of patients were skeletally immature. Time to failure after primary ACL reconstruction was 1.28 years (SD, 1.1) and revision surgery was performed 1.56 years (SD, 1) after the index procedure. Revision graft type included allograft (61.1%), patellar tendon (21.1%), hamstring (16.7%), and iliotibial band (1.1%). There was a 20% graft reinjury rate. Subsequent surgical procedures after revision were required in 25.5% of knees. Twenty percent of revision reconstructions had contralateral ACL injuries, and this percentage was higher (33%) among those who went on to injure their revision graft. Median outcome scores collected from 44 patients (50%) at a mean of 5.1 years following surgery (SD, 3.4) were: Pedi-IKDC 79.9, Lysholm 84.5, and Tegner 9.0. Sixty-nine percent of patients reported returning to sports, however, only 55.2% of these reported being able to return to the same level of play. Revision ACL reconstruction in pediatric patients was associated with suboptimal patient-reported outcomes, high complication rates, relatively high graft retear rates, high risk of contralateral ACL injury, and compromised return to sports rates. Level IV.

Revision Anterior Cruciate Ligament Reconstruction Outcomes in Younger Patients: Medial Meniscal Pathology and High Rates of Return to Sport Are Associated With Third ACL Injuries

Background: There are limited data evaluating the outcomes of revision anterior cruciate ligament (ACL) reconstruction surgery in younger patients despite recent reports that the rates of graft rupture are higher in young cohorts. Purpose: To explore the outcomes of revision ACL reconstruction surgery in younger patients with the specific aims of determining the rates of third ACL injury and whether knee pathology at the time of revision surgery and return to sport were associated with further injury. Study Design: Case-control study; Level of evidence, 3. Methods: The study cohort consisted of 151 consecutive patients who were aged 25 years or younger at the time of their first revision ACL reconstruction. The number of subsequent ACL injuries (graft rerupture or contralateral injury to the native ACL) was determined at a mean follow-up time of 4.5 years (range, 2-9 years). Surgical details were recorded, along with a range of sport participation outcomes. Contingency tables were used to assess the associations between subsequent ACL injury and return to sport, knee pathology, and the drilling of new femoral or tibial tunnels at revision surgery. Results: The follow-up rate was 85% (128/151). Graft reruptures occurred in 20 patients (16%) at a mean time of 2 years after revision surgery. Contralateral ACL injuries occurred in 15 patients (12%) at a mean time of 3.9 years. The total number of patients who had a third ACL injury was 35 (27%). There was a significant association between having medial meniscal pathology and sustaining a graft rerupture (P = .03), but there was no association between graft rerupture and using the same tunnels from the primary procedure at revision surgery. After revision reconstruction, 68% of patients (95% CI, 55%-71%) returned to their preinjury level of sport, compared with 83% (95% CI, 69%-84%) after primary reconstruction in the same patients. Those who had a third ACL injury had a significantly higher rate of return to preinjury sport (83%) after the revision procedure than did the group that did not have further ACL injuries (62%, P = .02). Conclusion: Younger patients are at significant risk of having multiple ACL injuries. The high rate of third ACL injuries presents a significant issue for future knee health in these young athletes. Medial meniscal pathology and returning to high-risk sport are factors that are significantly associated with the high multiple ACL injury rate in the young.

Risk Factors for Contralateral ACL Injury: A Single Institution Case-Control Study.

Our purpose was to evaluate if there is any association between requiring contralateral anterior cruciate ligament (ACL) reconstruction and various: (1) demographics, (2) patient characteristics, and (3) surgery-specific factors. A prospectively collected database at a single institution was queried to find all patients who underwent primary ACL reconstruction between 2012 and 2014. We identified 312 primary ACL reconstruction patients with a mean age of 24 years and a mean follow-up of 3 years (range, 2-5 years). This cohort was compared with all those who had primary ACL reconstructions during the same time period without a contralateral procedure. We evaluated: (1) incidence, (2) demographic variables, (3) family history, (4) graft choice, (5) activity causing injury, and (6) mechanism of injury (contact versus noncontact). There were 16 patients (4.8%) with a mean age of 21 years and a mean follow-up of 3 years that required a contralateral reconstruction. More females required contralateral reconstruction when compared with the control cohort (p = 0.049). However, there was no difference in the mean age between the cohorts (p = 0.32). Those who underwent reconstruction using a tibialis anterior allograft were far more likely to require a contralateral reconstruction (p = 0.0002). Bone-tendon-bone patellar autograft (p = 0.16), hamstring autograft (p = 0.76), and hamstring allograft (p = 0.68) had similar incidences of contralateral ACL injury. Lacrosse was associated with higher risk of contralateral procedure (p = 0.03). Mechanism of injury had no association of contralateral reconstruction (p = 0.71). We found that those with the highest risk of contralateral ACL reconstruction following their index procedure were females, those with tibialis anterior allografts, and those who had their ipsilateral injury while playing lacrosse. These data may be used by practitioners when educating patients regarding their potential for requiring a contralateral reconstruction following their index procedure.

20-Year Outcomes of Anterior Cruciate Ligament Reconstruction With Hamstring Tendon Autograft: The Catastrophic Effect of Age and Posterior Tibial Slope

Background: No well-controlled studies have compared the long-term outcome of anterior cruciate ligament (ACL) reconstruction with hamstring tendon autograft between adolescents and adults. Increased posterior tibial slopes (PTSs) have been reported in the ACL-injured versus controls, but the effect of PTS on the outcome after reconstruction is relatively unexplored. Purpose: To compare the prospective longitudinal outcome of “isolated” ACL ruptures treated with anatomic endoscopic ACL reconstruction using hamstring tendon autograft over 20 years in adolescent and adult cohorts and to examine factors for repeat ACL injury. Study Design: Case-control study; Level of evidence, 3. Methods: A single-surgeon series of 200 consecutive patients undergoing isolated primary ACL reconstruction with hamstring tendon autograft were prospectively studied. Subjects were assessed preoperatively and at 2, 7, 15, and 20 years postoperatively. Outcomes included International Knee Documentation Committee (IKDC) Knee Evaluation, IKDC subjective scores, KT-1000 instrumented laxity testing, and radiological evaluation of degenerative change and medial tibial slope. Twenty-year outcomes were compared between those who underwent surgery at the age of 18 years or younger (adolescent group, n = 39) and those who underwent surgery when older than 18 years (adult group, n = 161). Results: At 20 years, 179 of 200 subjects were reviewed (89.5%). ACL graft rupture occurred in 37 subjects and contralateral ACL injury in 22 subjects. Of those with intact ACL grafts at 20 years, outcomes were not statistically different between adolescents and adults for the variables of IKDC subjective score (P = .29), return to preinjury activity level (P = .84), current activity level (P = .69), or degree of radiological degenerative change at 20 years (P = .51). The adolescent group had a higher proportion of grade 1 ligamentous laxity testing compared with the adult group (P = .003). Overall, ACL graft survival at 20 years was 86% for adults and 61% for adolescents (hazard ration, 3.3; P = .001). The hazard for ACL graft rupture was increased by 4.8 in adolescent males and 2.5 in adolescent females compared with adults. At 20 years, the ACL survival for adolescents with a PTS of ≥12° was 22%. The hazard for ACL graft rupture was increased by 11 in adolescents with a PTS of ≥12° (P = .001) compared with adults with a PTS <12°. Conclusion: Repeat ACL injury after isolated ACL reconstruction is common, occurring in 1 in 3 over 20 years. In the absence of further injury, isolated ACL reconstruction using this technique was associated with good long-term outcomes with respect to patient-reported outcomes and return to sports, regardless of age. However, mild ligament laxity and ACL graft rupture after ACL reconstruction are significantly more common in adolescents, especially adolescent males, compared with adults. PTS of 12° or more is the strongest predictor of repeat ACL injury, and its negative effect is most pronounced in adolescents.

Geometric Characteristics of the Knee Are Associated With a Noncontact ACL Injury to the Contralateral Knee After Unilateral ACL Injury in Young Female Athletes

Background: Contralateral anterior cruciate ligament (CACL) injury after recovery from a first-time ACL rupture occurs at a high rate in young females; however, little is known about the risk factors associated with bilateral ACL trauma. Hypothesis: The geometric characteristics of the contralateral knee at the time of the initial ACL injury are associated with risk of suffering a CACL injury in these female athletes. Study Design: Case-control study; Level of evidence, 3. Methods: Sixty-two female athletes who suffered their first noncontact ACL injury while participating in sports at the high school or college level were identified, and geometry of the femoral notch, ACL, tibial spines, tibial subchondral bone, articular cartilage surfaces, and menisci of the contralateral, uninjured, knee was characterized in 3 dimensions. We were unable to contact 7 subjects and followed the remaining 55 until either a CACL injury or an ACL graft injury occurred or, if they were not injured, until the date of last contact (mean, 34 months after their first ACL injury). Cox regression was used to identify risk factors for CACL injury. Results: Ten (18.2%) females suffered a CACL injury. Decreases of 1 SD in femoral intercondylar notch width (measured at its outlet and anterior attachment of the ACL) were associated with increases in the risk of suffering a CACL injury (hazard ratio = 1.88 and 2.05, respectively). Likewise, 1 SD decreases in medial-lateral width of the lateral tibial spine, height of the medial tibial spine, and thickness of the articular cartilage located at the posterior region of the medial tibial compartment were associated with 3.59-, 1.75-, and 2.15-fold increases in the risk of CACL injury, respectively. Conclusion: After ACL injury, subsequent injury to the CACL is influenced by geometry of the structures that surround the ACL (the femoral notch and tibial spines). This information can be used to identify individuals at increased risk for CACL trauma, who might benefit from targeted risk-reduction interventions.

Over-the-top ACL Reconstruction Plus Extra-articular Lateral Tenodesis With Hamstring Tendon Grafts: Prospective Evaluation With 20-Year Minimum Follow-up

Background: There are few published studies with very long-term follow-up of combined intra- and extra-articular anterior cruciate ligament (ACL) reconstruction. Purpose: To analyze clinical and radiographic outcomes of over-the-top ACL reconstruction plus extra-articular lateral tenodesis with autologous hamstrings at minimum 20-year follow-up. Study Design: Case series; Level of evidence, 4. Methods: Of 60 originally eligible patients who underwent over-the-top ACL reconstruction with double-stranded hamstring tendon (leaving intact graft tibial insertions) and extra-articular lateral plasty (performed with the remnant part of tendons), 52 were prospectively evaluated at a minimum 20-year follow-up (mean follow-up, 24 years; 41 men, 11 women; mean age at time of surgery, 25.5 ± 7.6 years). Twenty-nine patients were available for prospective evaluations: clinical (Lysholm, Tegner, and objective International Knee Documentation Committee [IKDC]), instrumented (KT-2000), and radiographic (standard, long-standing, and Merchant views). Subjective KOOS (Knee injury and Osteoarthritis Outcome Score) and objective inertial sensor pivot-shift analysis (KiRA) were carried out at final follow-up. Twenty-three patients were investigated by phone interview for subjective Tegner score and documented complications, rerupture, or revision surgery. Results: At final follow-up, mean Lysholm score was 85.7 ± 14.6; median Tegner score, 4 (range, 3-5); sport activity resumption, 86.2%; and objective IKDC score, good or excellent in 86% of patients (31%, A; 55%, B). Only 3 of 26 patients (12%) had >5-mm manual maximum KT-2000 side-to-side difference. KiRA system documented positive pivot-shift (>0.9-m/s2 tibial acceleration side-to-side difference) in these 3 of 26 patients (12%). Statistically significant changes were as follows: decrease in Tegner score from 7 (range, 6-8) at 5-year follow-up to 4 (range, 3-5) at 10 years (P < .0001) and decrease in Lysholm score from 96.1 ± 7.3 at 10-year follow-up to 85.7 ± 14.6 at 20 years (P = .0003). Radiographic evaluation demonstrated significant difference of medial joint space between injured and healthy knees in patients with concomitant medial meniscectomy (n = 8, 3.2 ± 0.6 vs 5.0 ± 1.8 mm, P = .0114). No significant differences were reported regarding lateral or patellofemoral joint space. One patient (2%) experienced rerupture, with 3 of 52 (5.8%) having a contralateral ACL injury (excluded from KT-2000 and radiographic evaluations). Overall, 4 of 29 clinical failures (objective IKDC, KT-2000) and 1 rerupture among 52 patients were registered at final follow-up. Conclusion: Studied surgical technique demonstrated good results in laxity control at 20-year minimum follow-up. The lateral extra-articular plasty associated with ACL reconstruction did not generate lateral knee or patellofemoral osteoarthritis. The factor increasing osteoarthritis was meniscectomy.

Thirty-Year Experience With ACL Reconstruction Using Patellar Tendon: A Critical Evaluation of Revision and Reoperation

Background:During the preoperative discussion prior to anterior cruciate ligament reconstruction (ACLR), patients are often interested in data regarding rates of revision reconstruction, reoperation, concomitant pathologic changes, and future contralateral ACL injury.Purpose:To analyze a single surgeon’s experience with primary and revision ACLR over a 30-year interval, focusing on incidence and risk factors for revision and reoperation.Study Design:Case series; Level of evidence, 4.Methods:Patients who underwent ACLR from 1986 to 2016 were identified from a prospectively maintained database. Covariates of interest included age, sex, time, and graft selection. Outcomes of interest included revision and reoperation rates.Results:A total of 2450 ACLRs (mean patient age, 29 years; 58% male) were reviewed. Among primary ACLRs performed (n = 2225), 68% entailed bone–patellar tendon–bone (BTB) autograft and 30% entailed BTB allograft. Patients undergoing ACLR with autograft and allograft had a mean age of 22 and 37 years, respectively. The rate of revision ACLR was 1.8% and 3.5% for primary and revision cases, respectively. An increased rate of revision was noted among females compared with males (2.6% vs 1.2%) and among allografts compared with autografts (2.7% vs 1.3%). Low-dose irradiation did not affect allograft revision rates. The nonrevision reoperation rate following primary ACLR was 12%. The nonrevision reoperation rate was lower among primary cases reconstructed with allograft than autograft (9% vs 13%). Seventeen percent of cases involved concomitant meniscal repair and, among these, 13% required revision meniscal surgery. The rate of contralateral ACLR was 5.3%Conclusion:This information is useful in the informed consent process, for perioperative decision making regarding graft choice, and for identifying patients who are at risk for injuring the uninvolved knee.

Increased Risk of Graft Failure after ACL Reconstruction in Young Female Athletes with Hamstring Grafts

Objectives:The incidence of second anterior cruciate ligament (ACL) injury after ACL reconstruction (ACLR) and return to sport (RTS) in a young, active population is likely between 25-33% with the greatest risk in the first 12 months after RTS. Although the use of allograft tissue in young athletes has been reported to result in increased risk of graft failure, differences in graft and contralateral ACL injury risk between patients who receive a hamstrings (HS) autograft and bone-patellar tendon- bone (BTB) autograft has yet to be reported in a young, athletic population. The tested hypothesis was that the relative risk (RR) of ipsilateral graft failure would be higher in young, active patients who receive an ACLR with a hamstrings graft, while the RR of contralateral ACL injury would be higher in patients who receive and ACLR with a BTB autograft.Methods:One hundred thirty-nine subjects (99 female/40 male) with a mean age of 16.9±2.0 years old (range: 13-25 y/o) underwent ACLR with either a HS autograft (n=79) or a BTB autograft (n=60) and were released to return to pivoting/cutting sport. These patients were enrolled in a prospective, observational cohort study and were tracked for incidence of 2nd ACL after ACLR for a median of 73 months. Thirty-four (24.5%) suffered a 2nd ACL injury. Fisher’s exact tests were used to determine whether graft choice (HS vs. BTB) was associated with risk of either ipsilateral graft failure or contralateral ACL injury. Sub-group analyses by sex were also conducted.Results:Patients who underwent ACLR with HS graft (n=79) sustained 14 ipsilateral tears and 6 contralateral ACL injuries. Patients who received an ACLR with BTB (n=62) sustained 2 ipsilateral tears and 12 contralateral ACL injuries (Table 1). Patients who received an ACLR with HS graft were 6 times more likely (RR=6.2; 95% CI: 1.4-28.7) to suffer a graft failure after RTS than the BTB group. In the first 12 months after RTS, the HS graft patients were nearly 10 times (RR=9.5; 95% CI: 1.2-76.1) more likely to suffer an ipsilateral graft failure. Patients with a HS graft were 3 times less likely (RR=0.33; 95%CI: 0.12-0.935) to suffer a contralateral ACL injury and nearly 7 times less likely (RR=0.15, 95%CI: 0.031-0.709) to suffer a contralateral ACL injury in the first 12 months after RTS compared to the BTB group. When the cohort was divided by sex, females with HS grafts were significantly more likely to sustain a graft failure in the first 12 months after RTS (p=0.008) and by final follow-up (p=0.002) compared to females with BTB graft. Females with HS grafts were 3 times less likely (RR=0.30; 95%CI: 0.095-0.943) to suffer a contralateral ACL injury than females with BTB graft and 6 times less likely (RR=0.17; 95%CI: 0.034-0.846) to suffer contralateral ACL injury in the first year after RTS. Males demonstrated no significant difference in ipsilateral or contralateral injury risk based on graft type.Conclusion:Young, active females who return to pivoting and cutting sports after ACLR with HS autograft are at greater risk to suffer a graft failure and reduced risk to suffer a contralateral ACL injury compared to females who undergo ACLR with BTB graft tissue. No significant differences in 2nd ACL injury risk based on graft type were observed in the male patients.Table 1:Distribution of 2nd ACL Injury after ACLR and Return to Sport (RTS) All Subjects (n=139) HS (n=79)BTB (n=60)p-valueIpsilateral (RTS+1 year)11 (13.9%)1 (1.7%)0.013Ipsilateral (Overall)14 (17.7%)2 (3.4%)0.014Contralateral (RTS+1 year)2 (2.2%)9 (15.0%)0.010Contralateral (Overall)6 (7.6%)12 (20.0%)0.031 Female (n=99) HS (n=55}BTB (n=44)p-valueIpsilateral (RTS+l year)8 (14.5%)0 (0%)0.008Ipsilateral (Overall)10 (18.2%)0 (0%)0.002Contralateral (RTS+1 year)2 (3.6%)8 (18.2%)0.021Contralateral (Overall)5 (9.1%)11 (25.0%)0.033 Male (n=40) HS (n=24)BTB (n=16)p-valueIpsilateral (RTS+1 year)3 (12.5%)1 (6.2%)0.638Ipsilateral (Overall)4 (16.7%)2 (12.5%)1.000Contralateral (RTS+I year)0 (0%)1 (6.2%)0.400Contralateral (Overall)1 (4.2%)1 (6.2%)1.000

Functional assessments for anterior cruciate ligament reconstruction return to sport

Despite technical advancements in anterior cruciate ligament (ACL) surgery, the high re-rupture and contralateral ACL injury rates following ACL reconstruction remain a clinically and economically relevant problem. ACL re-ruptures are multi-factorial, however premature return to sport and functional deficits are important causes for graft failure and contralateral ACL injuries. While various prevention programs exist, little is known about functional assessment following ACL reconstruction. Most of the functional tests are for research purposes only because of the associated high costs, time and personnel consumption. In order to integrate functional testing into the rehabilitation process and to subsequently improve patient care, test batteries must be clinically applicable. Many tests have been introduced and evaluated, but many of them reflect only limited aspects of the knee and lower limb function. Therefore, test batteries evaluating muscle strength, speed and agility, as well as neuromuscular control have been introduced. In order to properly interpret the test results however, comparison to normative data or longitudinal data are necessary to properly determine the return to sport.

Greater knee laxity after primary ACL reconstruction is associated with subsequent contralateral ACL injury in younger patients

Greater knee laxity after primary ACL reconstruction is associated with subsequent contralateral ACL injury in younger patients

Results Are Similar Two Years After Acute or Delayed Anterior Cruciate Ligament Reconstruction. A Randomized Controlled Trial

Objectives:Acute ACLR has been avoided since the 1990’s due to reports of postoperative stiffness. But are these risks still valid with modern arthroscopic techniques? The aim of this randomized controlled trial was to assess the impact of the time between injury and reconstruction on the outcome after ACLR. Our hypothesis was that acute ACLR with semitendinosus graft can be performed safely.Methods:The primary endpoint was ROM at three months after surgery. A power calculation revealed the need for 64 patients to detect a ROM difference of 5 degrees between the groups (5% significance level). 70 patients with a high recreational activity level (Tegner ≥6) who presented with an acute ACL injury were randomized to an acute reconstruction within 8 days from the injury or delayed reconstruction (after normalized ROM) 6-10 weeks after the injury. Fixation was with Endobutton in femur and a metallic interference screw in tibia. The rehabilitation was performed at the same physiotherapy center for all patients. Follow up assessment was performed by a physiotherapist not involved with the rehabilitation. The follow up at 24 months included ROM, Lachman, instrumented laxity with Rolimeter, pivot shift, one leg hop index, Biodex, IKDC, KOOS, Lysholm and Tegner Activity level, and a VAS question regarding knee function and the knee function’s effect on activity level.Results:Seventy percent of the patients were males, mean age at the time of surgery was 27 years (18 -41) and the median pre-injury Tegner level was 9 (6-10) with no differences between the groups. 64 (91%) patients were assessed at three months with no difference according to the primary endpoint. Median Tegner level was restored to pre-injury levels in both groups after one year, and did not change between one and two years. 63 (90%) patients were available for the 2-year follow up. There was one graft rupture and one contralateral ACL injury in both groups. There was additional surgery in 15% of the acute patients and in 31% in the delayed (n.s.). The mean instrumented laxity was 1.8 mm in the acute and 2.0 in the delayed group. There were no positive pivot shift in the acute group and 6 patients with grade 1 or not possible to perform in the delayed group (p=0.039). IKDC revealed no significant differences between the groups. Lysholm score was 87 in both groups. KOOS values showed no significant difference between the groups. VAS response to the question “How is your knee working on a scale from 0-100? (100 = best)” was 81 in the acute and 71 in the delayed group (p=0.1) and “How does your knee affect your activity level? (100 = no affection)” the mean score was 75 in the acute and 67 in the delayed group (p=0.3). Functional strength (one leg hop index >90%) was 85% in the acute and 67% in the delayed group (n.s).Conclusion:We found no increased risk of arthrofibrosis after acute ACLR. Good results can be achieved at two years regardless of ROM and swelling in the acute stage.

The Effect of Postoperative KT-1000 Arthrometer Score on Long-Term Outcome After Anterior Cruciate Ligament Reconstruction

Background: Many long-term studies have looked at outcomes after anterior cruciate ligament reconstruction (ACLR), but none have correlated long-term outcomes with postoperative laxity greater than 5 mm. It has been stated previously that more than 5 mm of postoperative graft laxity constituted a procedural failure. Purpose: To directly compare tight grafts (<3 mm) and loose grafts (>5 mm) to determine the effect of graft laxity, as measured by KT-1000 arthrometer, after ACLR on long-term clinical outcomes. Study Design: Cohort study; Level of evidence, 2. Methods: The study included 171 consecutive patients who had undergone transtibial bone–patellar tendon–bone ACLR between 1992 and 1998. At 6, 12, and 24 months postoperatively (the immediate postoperative period), patients were evaluated. Group A included patients with a maximal side-to-side (STS) difference in the immediate postoperative period of less than 3 mm (tight grafts), and group B included patients with a maximal STS difference of greater than 5 mm (loose grafts). Any patient with a history of ipsilateral or contralateral ACLR or ACL injury, meniscectomy, or cartilage restoration was excluded. Patients were prospectively followed to long-term follow-up, when a telephone interview was conducted regarding knee function and to document Lysholm, Tegner, Knee injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) subjective outcome scores. Results: Eighty-seven patients met inclusion criteria: 66 tight grafts (group A) and 21 loose grafts (group B). The mean ± SD time to follow-up was 16.3 ± 1.5 years in group A (n = 46) and 16.8 ± 1.3 years in group B (n = 15). Tegner (P = .77), Lysholm (P = .85), KOOS (P = .96), and IKDC (P = .42) were found to have no statistically significant difference between groups at long-term follow-up. Both Tegner and Lysholm scores significantly improved in tight and loose grafts in the immediate postoperative period as well as at long-term follow-up compared with preoperatively. There were 2 ACL revisions in group A and none in group B. Eleven of 46 patients (24%) in group A required subsequent procedures versus 1 of 15 patients (6.7%) in group B (P = .146). Conclusion: Postoperative laxity of greater than 5 mm STS difference as measured by KT-1000 arthrometer does not appear to place patients at a worse clinical outcome at long-term follow-up, nor does it lead to significantly more subsequent procedures. In addition, transtibial ACLR can provide excellent clinical results at long-term follow-up.

Twenty-Year Outcome of a Longitudinal Prospective Evaluation of Isolated Endoscopic Anterior Cruciate Ligament Reconstruction With Patellar Tendon or Hamstring Autograft

Background: Long-term prospective studies of isolated endoscopic anterior cruciate ligament (ACL) reconstruction are limited and may include confounding factors. Purpose: This study aimed to compare the outcomes of isolated ACL reconstruction using the patellar tendon (PT) autograft and the hamstring (HT) autograft in 180 patients over 20 years. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 180 participants undergoing isolated ACL reconstruction between 1993 and 1994 were prospectively recruited. Evaluation was performed at 1, 2, 5, 7, 10, 15, and 20 years after surgery and included the International Knee Documentation Committee (IKDC) knee ligament evaluation with radiographic evaluation, KT-1000 arthrometer side-to-side difference, and subjective scores. Results: Over 20 years, there were 16 patients (18%) and 9 patients (10%) with an ACL graft rupture in the HT and PT groups, respectively (P = .13). ACL graft rupture was associated with male sex (odds ratio [OR], 3.9; P = .007), nonideal tunnel position (OR, 3.6; P = .019), and age <18 years at the time of surgery (OR, 4.6; P = .003). The odds of a contralateral ACL rupture were increased in patients with the PT graft compared with patients with the HT graft (OR, 2.2; P = .02) and those aged <18 years at the time of surgery (OR, 3.4; P = .001). The mean IKDC scores at 20-year follow-up were 86 and 89 for the PT and HT groups, respectively (P = .18). At 20 years, 53% and 57% of the PT and HT groups participated in strenuous or very strenuous activities (P = .55), kneeling pain was present in 63% and 20% of the PT and HT groups (P = .018), and radiographic osteoarthritic change was found in 61% and 41% of the PT and HT groups (P = .008), respectively. Conclusion: Compared with patients who received the HT graft, patients who received the PT graft had significantly worse outcomes with regard to radiologically detectable osteoarthritis, kneeling pain, and contralateral ACL injury. At 20-year follow-up, both HT and PT autografts continued to provide good subjective outcomes and objective stability. However, further ACL injury is common, particularly in male individuals, younger patients, and those with tunnel malposition.

Exploring the High Reinjury Rate in Younger Patients Undergoing Anterior Cruciate Ligament Reconstruction

Background: Younger age is being increasingly recognized as a risk factor for anterior cruciate ligament (ACL) graft rupture and contralateral ACL injury after ACL reconstruction. Recent reports estimate second ACL injury rates to be in the range of 20% to 40%, which is a significant concern and requires further exploration. Purpose: The primary purpose was to determine the rates of graft rupture and injury to the contralateral native ACL in younger athletes. We also sought to explore the influence of sex and age groupings (<18 years vs 18-19 years at the time of surgery) on the risk of subsequent ACL injury. Study Design: Cohort study; Level of evidence, 3. Methods: The study cohort consisted of 354 consecutive patients who were younger than 20 years when they underwent their first primary hamstring tendon autograft ACL reconstruction. The number of subsequent ACL injuries (graft rupture or a contralateral injury to the native ACL) was determined at a mean follow-up of 5 years (range, 3-10 years). Subgroup analysis included sex and age (<18 years vs 18-19 years at the time of surgery) comparisons. Descriptive statistics were calculated for the timing of ACL graft rupture and contralateral ACL injury. Results: The overall follow-up rate was 89% (316/354). Graft ruptures occurred in 57 patients (18%) at an average time of 1.8 years after surgery. Almost half (47%) occurred within the first postoperative year, and 74% occurred within the first 2 years. The highest graft rupture rate of 28.3% was in the youngest males (<18 years), and this was significantly higher than in females of the same age (12.9%), as well as in male patients older than 18 years (13.8%). Contralateral ACL injuries occurred in 56 patients (17.7%) at an average time of 3.7 years after surgery. There were no significant age- or sex-based differences for contralateral ACL injuries. The total number of patients who had at least 1 further ACL injury subsequent to the primary surgery was 110 (35%). Conclusion: The high rate of subsequent ACL injury in younger patients was confirmed. Early graft ruptures were more prevalent in patients who underwent surgery when they were younger than 18 years versus those in the 18- to 19-year age group. Males had higher rates of graft rupture than did females, with the youngest males (<18 years) at the highest risk in the investigated cohort.

Are Female Soccer Players at an Increased Risk of Second Anterior Cruciate Ligament Injury Compared With Their Athletic Peers?

Background: Female soccer players have a well-known risk for anterior cruciate ligament (ACL) injury, but few studies have reported on second ACL injuries in this population. Purpose: To (1) report the rates of subsequent ACL injury (ipsilateral graft rupture or contralateral tear) in competitive female soccer players, (2) compare these rates with those of other female athletes of similar competitive level, (3) determine risk factors for second ACL injury, and (4) report clinical outcome scores in this population. Study Design: Cohort study; Level of evidence, 3. Methods: The medical records at a single institution were reviewed for female patients who were injured during a competitive athletic event and treated with primary ACL reconstruction (ACLR) between 1998 and 2013. Patients were followed for a mean of 68.8 months postoperatively (range, 24-115.2 months). Clinical outcome was obtained via Lysholm and International Knee Documentation Committee (IKDC) scores. Soccer players were matched 1:1 to non-soccer athletes for age, activity level, and graft type. Results: A total of 180 female ACLR patients with a mean ± SD age of 19.6 ± 6.9 years met the study inclusion and exclusion criteria (90 soccer players and 90 non-soccer players). Soccer players sustained more second ACL injuries, including both graft failures (11% vs 1%; P < .01) and contralateral ACL tears (17% vs 4%; P < .01), compared with non-soccer players. Of the 67 patients who returned to soccer after ACLR (mean age, 17.5 years; range, 13-27 years), significantly more had graft tears compared with those who did not return to soccer (15% vs 0%, respectively; P = .04); however, the difference in contralateral ACL tears (19% for returning players vs 9% for those who did not return; P = .34) was not significant. Relatively older age (odds ratio, 1.5 per year; P = .03) was a significant risk factor for ACL graft tear but not for contralateral ACL injury. Both groups had similar mean Lysholm (96 vs 95) and IKDC scores (95 vs 96) at final follow-up. Conclusion: Twenty-eight percent of all female soccer players and 34% of those players who returned to soccer had a second ACL tear. Soccer players had an increased rate of both graft tear and contralateral ACL injury compared with similar non-soccer athletes. Older age and return to soccer were significant risk factors for graft rupture.

Revision ACL Reconstruction in Children and Adolescents

Results of revision ACL reconstruction in pediatric patients has not been well studied. The purpose of this study was to assess the demographics, technique, and results of ACL revision in children and adolescents. This was a retrospective case series and outcomes assessment of all pediatric/adolescent patients (<18 years) who underwent revision ACL surgery at a single institution. Charts were reviewed for patient demographics, injury characteristics, operative details, surgical complications, and patient outcome. Patient-oriented outcome measures were also sent to all patients and included the Pedi-IKDC, Tegner Activity Scale, Lysholm Knee Score, and a self-designed Physical Activity Survey to assess return to sport. Ninety revision ACL reconstructions were performed in 88 patients. Average patient age at the time of revision was 16.6 years (SD 1.69), and 28.8% were skeletally immature. Time to failure after primary ACL reconstruction was 1.28 years (SD 1.06), and the most common mechanism of failure was noncontact sports injuries. 74.4% had additional intraarticular injuries that required surgical intervention at the time of revision. Revision graft type included allograft (61.1%), patellar tendon (21.1%), hamstring (16.7%), and iliotibial band (1.1%). There was a 20% graft reinjury rate. Additional procedures after revision were required in 25.5% of knees, and 20% of revision reconstructions had contralateral ACL injuries. 50% of patients completed outcome measures with an average time since revision of 5.1 years. The mean outcome scores were: Pedi-IKDC 71.7 (SD 12.6), Lysholm 79 (SD 13.2), Tegner 6.6 (range 6-10). 69% of patients reported returning to sports at an average of 8.9 months (3-36), however, only 55.2% of these reported being able to return to the same level of play. Revision ACL reconstruction in pediatric patients was associated with worse functional outcome, lower activity level, higher rates of graft retearing, and lower return to sports rates than primary ACL reconstruction.

Fate of the Young Patient Undergoing Anterior Cruciate Ligament Reconstruction

Objectives:Younger age has been increasingly recognised as a risk factor for ACL graft rupture and contralateral ACL injury following ACL reconstruction. The purpose of the study was to evaluate the re-injury rate and explore factors that might be associated with increased risk.Methods:In this observational study, a cohort of 362 consecutive patients was identified from patients undergoing primary ACL reconstruction by a single surgeon form December 2004 to February 2012. Patients were under 20 years at the time of surgery and had a normal contralateral knee. The incidence of subsequent ACL injuries (graft rupture or contralateral ACL injury) was determined at a mean follow up time of 5 years (range 3-10). For further analysis the group was divided according to gender and age: under 18 or 18-19 at the time of surgeryResults:The overall follow up rate was 89% (40/362 patients were unable to be contacted). Graft ruptures occurred in 60 patients (16.6%) at an average time of 1.9 years. Almost half (47%) occurred within the first postoperative year. The graft rupture rate was significantly higher in males (19.5%) than females (11.1%). The rupture rate in the youngest males (under 18) was the highest at 25.4%, which was significantly higher than females of the same age (11.7%) and males over 18 years (12.7%). Of the early graft ruptures, 75% occurred in the under 18 group. Contralateral ACL injuries occurred in 57 patients (15.7) at a longer average time of 3.7 years. There were no gender or age differences for contralateral ACL injuries. There were 4 patients who had a graft rupture as well as a contralateral ACL injury; therefore the total number of patients who had at least one further ACL injury subsequent to the primary surgery was 113 (31.2%).Conclusion:The high rate of subsequent ACL injury in younger patients was confirmed. Early graft ruptures are more prevalent in the very young and gender differences are more apparent for graft rupture, where the youngest males are at high risk. The high incidence of multiple ACL injuries in such a young cohort is concerning for future knee health.