Background Single-legged hop tests are commonly used functional performance measures that can capture limb asymmetries in patients after anterior cruciate ligament (ACL) reconstruction. Hop tests hold potential as predictive factors of self-reported knee function in individuals after ACL reconstruction. Hypothesis Single-legged hop tests conducted preoperatively would not and 6 months after ACL reconstruction would predict self-reported knee function (International Knee Documentation Committee [IKDC] 2000) 1 year after ACL reconstruction. Study Design Cohort study (prognosis); Level of evidence, 2. Methods One hundred twenty patients who were treated with ACL reconstruction performed 4 single-legged hop tests preoperatively and 6 months after ACL reconstruction. Self-reported knee function within normal ranges was defined as IKDC 2000 scores greater than or equal to the age- and sex-specific normative 15th percentile score 1 year after surgery. Logistic regression analyses were performed to identify predictors of self-reported knee function within normal ranges. The area under the curve (AUC) from receiver operating characteristic curves was used as a measure of discriminative accuracy. Results Eighty-five patients completed single-legged hop tests 6 months after surgery and the 1-year follow-up with 68 patients classified as having self-reported knee function within normal ranges 1 year after reconstruction. The crossover hop and 6-m timed hop limb symmetry index (LSI) 6 months after ACL reconstruction were the strongest individual predictors of self-reported knee function (odds ratio, 1.09 and 1.10) and the only 2 tests in which the confidence intervals of the discriminatory accuracy (AUC) were above 0.5 (AUC = 0.68). Patients with knee function below normal ranges were over 5 times more likely of having a 6-m timed hop LSI lower than the 88% cutoff than those with knee function within normal ranges. Patients with knee function within normal ranges were 4 times more likely to have a crossover hop LSI greater than the 95% cutoff than those with knee function below normal ranges. No preoperative single-legged hop test predicted self-reported knee function within normal ranges 1 year after ACL reconstruction (all P > .353). Conclusion Single-legged hop tests conducted 6 months after ACL reconstruction can predict the likelihood of successful and unsuccessful outcome 1 year after ACL reconstruction. Patients demonstrating less than the 88% cutoff score on the 6-m timed hop test at 6 months may benefit from targeted training to improve limb symmetry in an attempt to normalize function. Patients with minimal side-to-side differences on the crossover hop test at 6 months possibly will have good knee function at 1 year if they continue with their current training regimen. Preoperative single-legged hop tests are not able to predict postoperative outcomes.

To our knowledge, this is the first study to identify the PASS thresholds for the IKDC-SKF and the KOOS subscales for individuals 1 to 5 years after ACL reconstruction. By identifying threshold values for the PASS, this study provides additional information to facilitate interpretation of the IKDC-SKF and KOOS in daily practice and clinical research related to ACL reconstruction.

Background No gold standard exists for identifying successful outcomes 1 and 2 years after operative and non-operative management of anterior cruciate ligament (ACL) injury. This limits the ability of researcher and clinicians to compare and contrast results of interventions. Purpose to establish a consensus based on expert consensus of measures that define successful outcomes 1 and 2 years after ACL injury or reconstruction. Methods Members of international sports medicine associations, including the American Orthopaedic Society for Sports Medicine (AOSSM), the European Society for Sports Traumatology, Surgery, and Knee Arthroscopy (ESSKA), and the American Physical Therapy Association (APTA), were sent a survey via e-mail. Blinded responses were analyzed for trends with frequency counts. A summed importance percentage (SIP) was calculated and 80% SIP operationally indicated consensus. Results 1779 responses were obtained. Consensus was achieved for six measures in operative and non-operative management: the absence of giving way, patient return to sports, quadriceps and hamstrings strength greater than 90% of the uninvolved limb, the patient having no more than a mild knee joint effusion, and using patient reported outcomes (PRO). No single PRO achieved consensus, but threshold scores between 85 and 90 were established for PROs concerning patient performance. Conclusion The consensus identified six measures important for successful outcome after ACL injury or reconstruction. These represent all levels of the International Classification of Functioning; effusion, giving way, muscle strength (body structure and function), PRO (activity and participation), and return to sport (participation) and should be included to allow for comparison between interventions.

B Clinicians should administer appropriate clinical or field tests that reproduce pain and assess lower-limb movement coordination, such as squatting, step-downs, and single-leg squats. These tests can assess a patient's baseline status relative to pain, function, and disability; global knee function; and changes in status throughout the course of treatment. EXAMINATION -ACTIVITY LIMITATIONS/ PHYSICAL IMPAIRMENT MEASURESC When evaluating a patient with PFP over an episode of care, clinicians may assess body structure and function, including measures of patellar provocation, patellar mobility, foot position, hip and thigh muscle strength, and muscle length.

STUDY DESIGN Cohort study, cross-sectional. OBJECTIVES To determine if self-reported knee function assessed with the International Knee Documentation Committee 2000 Subjective Knee Form (IKDC2000) could discriminate between successful and non-successful performance on return to activity criteria (RTAC) tests after anterior cruciate ligament (ACL) reconstruction. BACKGROUND Rehabilitation specialists are challenged in selecting appropriate performance-based and patient-reported tests that can detect side-to-side asymmetries, assess global knee function, and determine a participant's readiness to return to activity after ACL reconstruction. A simple tool or questionnaire that could identify athletes with neuromuscular impairments or activity limitations could provide rehabilitation specialists crucial data pertinent to their current knee function and their readiness to return to higher level activities. METHODS One hundred fifty-eight Level I/II athletes 6 months after ACL reconstruction and 141 athletes 12 months after ACL reconstruction completed a functional test battery to determine readiness to return to activity and the IKDC2000 to determine self-reported knee function. For each athlete, status on return to activity tests criteria was dichotomized as “Passed” or ”Failed” and status on the IKDC2000 scores was dichotomized as being “within” or “below age- and sex-matched normal ranges”. Comparisons were made between status on RTAC and IKDC2000 using Chi-square tests. Accuracy statistics were also calculated. RESULTS Six months after ACL reconstruction, 112 athletes (70.9%) failed RTAC and 76 (48.1%) were classified as having self-reported knee function below normal ranges. Among the 76 participants with IKDC2000 scores below normal ranges, 69 (90.8%) failed RTAC test battery (P<.001). However, among the 82 participants whose IKDC2000 scores were within normal limits at 6 months, only 39 (47.6%) passed RTAC test battery (P=.74). Twelve months after ACL reconstruction, 67 athletes (47.5%) failed RTAC and 31 (78.0%) had knee function below normal ranges. Among the 31 participants with IKDC2000 scores below normal ranges, 25 (80.6%) failed RTAC test battery (P<.001). However, among the 110 participants whose IKDC2000 scores were within normal limits at 12 months, only 68 (61.8%) passed RTAC test battery (P=.017). CONCLUSION The IKDC2000 may be a clinically relevant tool to determine the timeliness or necessity of RTAC testing. For scores obtained 6 and 12 months after ACL reconstruction, low IKDC2000 scores were reasonably indicative of failure on RTAC test battery, whereas normal IKDC2000 scores were not predictive of passing scores on the RTAC test battery.

Purpose The aims of this study were to evaluate the functional recovery before and after ACL reconstruction and to evaluate the sensitivity to change in performance-based and self-report outcomes prior to and after ACL reconstruction and to determine if these changes represent clinically relevant improvement. Methods Eighty-three athletes participated in this study. Athletes were tested after an ACL injury, after pre-operative training, and 6 and 12 months after ACL reconstruction. Athletes completed quadriceps strength testing, hop testing, and self-reported questionnaires for knee function (International Knee Documentation Committee subjective knee form, Knee Outcome Survey-Activities of Daily Living Scale, and the Global Rating Scale of Perceived Function) at each testing period. Results A significant interaction of limb by time was seen in normalized quadriceps strength, and single, triple, and 6-meter timed hop, where the involved limb improved more than the uninvolved limb over time. A main effect of time was noted for performance-based limb symmetry indexes and self-report measures. Conclusion Limb-to-limb asymmetries are reduced and normal limb symmetry is restored after perturbation training and aggressive quadriceps strengthening and returned to similar levels 6 months after reconstruction. Performance-based values on the involved limb and self-reported outcomes are sensitive to change over time and these were clinically relevant improvements. Level of evidence Level II prognostic study

Background Quadriceps strength deficits are ubiquitous after anterior cruciate ligament (ACL) injury. Deficits prior to surgery can influence knee function post-operatively. Inhibition contributes to quadriceps strength deficits after an ACL injury. Body mass index, meniscal injury, and sex influence functional outcomes after ACL reconstruction. The purpose of this study is to examine the relationship of pre-operative quadriceps strength and post-operative knee function and to investigate how other pre-operative factors may influence this relationship. Methods After an ACL injury, subjects received pre-operative rehabilitation and performed quadriceps strength testing. Subjects underwent reconstruction and post-operative rehabilitation. Six months after ACL reconstruction, subjects completed the International Knee Documentation Committee 2000 subjective form (IKDC2000). Linear regression models were developed using IKDC2000 scores at 6 months after ACL reconstruction as the dependent variable. Results Fifty-five subjects had complete pre-operative data and IKDC2000 scores at 6 months after ACL reconstruction. Pre-operative involved quadriceps strength was a significant predictor for IKDC2000 scores 6 months after ACL reconstruction. Sex, meniscal injury, pre-operative BMI, and pre-operative involved quadriceps activation ratio were not significant predictors in the regression model. Conclusions Pre-operative quadriceps strength can predict IKDC2000 scores 6 months after ACL reconstruction. Deficits in pre-operative quadriceps strength influence self-reported function 6 months after surgery. Factors that are known to influence quadriceps strength and self-reported outcomes do not influence the relationship between pre-operative quadriceps strength and post-operative IKDC2000 scores.

The maturity of quadriceps tendon with bone block was better in comparison with hamstring 6 months after anatomic SB ACL reconstruction. This study is clinically relevant in that modifying the individual rehabilitation according to the extent of graft maturity may be necessary to optimize patient function and prevent re-injury of the ACL graft.