Single-leg vertical jump test as a functional test after anterior cruciate ligament reconstruction

Limb Symmetry Index of Single-Leg Vertical Jump vs. Single-Leg Hop for Distance After ACL Reconstruction: A Systematic Review and Meta-analysis

CONTEXT

The limb symmetry index (LSI) is recommended as a milestone of return to play (RTP), and relying on the LSI value of a single-leg hop for distance (SLHD) test may overestimate rehabilitation status. Identifying a more reliable functional test can help to carefully make decisions for RTP.

OBJECTIVE

The aim was to compare the LSI value of the SLHD test with that of a single-leg vertical jump (SLVJ) test after anterior cruciate ligament reconstruction (ACLR) and determine which test provides lower LSI values.

DATA SOURCES

The PubMed, Web of Science, Embase, and Cochrane Library databases were searched from inception to July 2022.

STUDY SELECTION

Observational studies with participants who had both SLHD and SLVJ tests after ACLR and LSI values of an SLHD and SLVJ were included. Disagreements were resolved after discussion between the 2 researchers.

STUDY DESIGN

Systematic review and meta-analysis.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Data on the primary outcomes (LSI values of the SLVJ and SLHD tests) were collected. Means and standard deviations (SDs) for each variable of interest were used to calculate standardized mean differences (SMDs).

RESULTS

A total of 12 studies met the inclusion criteria for the meta-analysis. A total of 587 patients underwent SLHD and SLVJ tests at different time points after ACLR. Compared with the SLHD test, the SLVJ test provided lower LSI values (SMD -0.42; 95% confidence interval (CI) -0.67 to -0.17). Subgroup analysis found that the SLVJ test provided a lower LSI value than the SLHD test in a specific period (approximately 7-18 months after ACLR, SMD -0.53; 95% CI -0.91 to -0.14) and a similar LSI value at other times.

CONCLUSION

The SLVJ test provided lower LSI values in a specific period (7-18 months after ACLR).

Lower extremity return to sport testing: A systematic review

BACKGROUND

Lower extremity injuries account for an enormous portion of sports medicine cases in the United States each year. Unfortunately, there are no uniform criteria for athletes to complete prior to returning to sport (RTS) following a lower extremity injury. Therefore, the purpose of this systematic review is to review current literature for joint-specific and global lower extremity testing to determine the most valid functional test that can be utilized to reduce the risk of re-injury as athletes RTS.

METHODS

A systematic search of PubMed, PubMed Central, Cochrane Library, OVID, and Embase databases was conducted for studies prior to May 2024 following PRISMA guidelines. ROBINS-I Tool was utilized for the risk of bias assessment.

RESULTS

Of 19,189 studies, 114 (0.6%) studies published prior to May of 2024 met inclusion criteria and were analyzed. Eighty five percent of articles discussed RTS for individuals with knee pathology. Furthermore, 82% specifically analyzed RTS following ACL reconstruction. The most common RTS test was isokinetic dynamometry testing which is seen in 73% of studies. Only 6.2% of studies analyzed RTS for individuals with hip pathology and only two studies analyzed RTS for patients with ankle injuries.

CONCLUSION

Even with the enormous amount of literature that exists regarding ACL injuries and testing there is no standardized criterion for RTS clearance. The suggested test batteries from this review can serve as a framework for future research and validation for joint-specific RTS functional testing.

Assessing the Relationship of Psychological Sport Readiness, Single-leg Vertical Jump, and Non-Sagittal Single-Leg Hops to Quadriceps Strength After Anterior Cruciate Ligament Reconstruction

Background

Limitations exist with current ACLR functional testing assessments that may be mitigated by including single-leg multi-directional testing.

Hypothesis/Purpose

To compare Anterior Cruciate Ligament-Return to Sport after Injury Scale (ACL-RSI) scores, limb symmetry index (LSI) of the single-leg vertical jump (SLVJ), single-leg medial rotation hop (SLMRH), single-leg lateral hop (SLLH), and isokinetic quadriceps strength between participants with an ACLR and healthy controls and assess predictors of quadriceps strength asymmetry. It was hypothesized that ACL-RSI scores and LSIs for all tests would differ between ACLR and healthy control groups and within the ACLR group a strong correlation would exist between all outcome measures and quadriceps strength.

Study Design

Cross-Sectional Study.

Methods

Twenty-six participants with an ACLR (median 13 months after surgery) and twenty-six matched healthy controls were recruited to participate in this study. Performance was assessed via SLVJ, SLMRH, SLLH, and isokinetic quadriceps strength. Between-group comparisons were made with independent t-tests and Mann-Whitney U test. Within the ACLR group, bivariate correlation and multivariate regression analysis were performed to assess the relationship between the outcome measures and quadriceps strength asymmetry.

Results

Significant between-limb differences were only identified in the ACLR group (p< 0.05): SLVJ LSI: 88.5%, SLMRH LSI: 93.6%, SLLH LSI: 92.7%, quadriceps strength LSI 80.9% - 83.9%, which were significantly lower (p <0.05) than the healthy control group. Within the ACLR group, a moderate-strong significant (p < 0.05) correlations existed with quadriceps strength and SLVJ (r=0.44-0.65), SLMRH (r =0.43-0.83), and SLLH (r=0.54-0.63); while ACL-RSI had a weak non-significant (p > 0.05) correlation with quadriceps strength (r= 0.12-0.30).

Conclusion

Single-leg multidirectional test LSIs were less in ACLR participants than matched healthy controls and all were directly related to quadriceps strength. Psychological readiness to return to sport was not related to quadriceps strength.

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

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

Impaired Symmetry in Single-Leg Vertical Jump and Drop Jump Performance 7 Months After ACL Reconstruction

Background

Anterior cruciate ligament reconstruction (ACLR) continues to be associated with a variable rate of return to sports and a concerning rate of further anterior cruciate ligament injury. Persistent functional deficits may explain these results and support the need to keep exploring lower limb functional indexes, especially during vertical jumping. This would help improve rehabilitation through the return-to-sports continuum and improve postoperative outcomes.

Hypothesis

Vertical jumping performance indexes are impaired among patients 7 months after ACLR.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

A total of 202 patients who underwent ACLR and 50 healthy participants performed single-leg vertical jump (SLVJ) and single-leg drop jump (SLDJ) testing. Jump height (H) as well as reactive strength index (RSI) were assessed and the limb symmetry index (LSI) of each parameter was compared between both groups. Vertical jumping indexes were also compared between healthy participants and the injured and contralateral legs of ACLR patients. Frequency analysis (chi-square test) of participants exhibiting an LSI >90% for each parameter was calculated in both groups. The level of association between SLVJ-H, SLDJ-H, and SLDJ-RSI was evaluated using the Pearson coefficient (r).

Results

At 6.6 ± 0.7 months (mean ± SD) postoperatively, participants after ACLR exhibited poorer LSI than the control group for all parameters (79.1 ± 14.8 vs 93.9 ± 4.5, 77.3 ± 14.6 vs 93.4 ± 5.2, and 71.9 ± 17.4 vs 93.4 ± 3.8; all P < .001; for the SLVJ-H, SLDJ-H, and SLDJ-RSI, respectively). Vertical jumping performance was lower on both injured and contralateral legs compared with healthy participants (all P < .001). Only 27%, 25%, and 16% of the ACLR patients exhibited an LSI >90% for the SLVJ-H, SLDJ-H, and SLDJ-RSI, respectively, in comparison with 80%, 72%, and 86% in the control group. Moderate correlations were observed between SLDJ-H and SLVJ-H (r = 0.494; P < .001) as well as between SLDJ-RSI and SLVJ-H (r = 0.488; P < .001) in the ACLR group.

Conclusion

Vertical jumping indexes (both symmetry and absolute values) were highly impaired 7 months after ACLR. Deficits were more marked for reactive strength ability. Clinicians should focus on restoring vertical jumping abilities to improve functional performance after ACLR.

Validity and Reliability of the Orthelligent Pro Sensor for Measuring Single-Leg Vertical Jump Height in Healthy Athletic Adults

The Orthelligent Pro sensor is a practicable, portable measuring instrument. This study assessed the validity and reliability of this sensor in measuring single-leg countermovement jumps. Fifty healthy athletic adults participated in two measurement sessions a week apart in time. They performed single-leg countermovement jumps on the force plate while wearing the Orthelligent Pro sensor on their lower leg. During the first measurement session, Tester 1 invited the participants to make three single-leg countermovement jumps; subsequently, Tester 2 did the same. For assessing the sensor's intratester reliability, Tester 1 again invited the participants to make three single-leg countermovement jumps during the second measurement session. The sensor's validity was assessed by using the force plate results as the gold standard. To determinate the agreement between two measurements, Bland-Altman plots were created. The intertester reliability (ICC = 0.99; 0.97) and intratester reliability (ICC = 0.96; 0.82) were both excellent. The validity calculated (i) on the basis of the mean value of three jumps and (ii) on the basis of the maximum value of three jumps was very high, but it showed a systematic error. Taking this error into account, physiotherapists can use the Orthelligent Pro sensor as a valid and reliable instrument for measuring the jump height of countermovement jumps.

How Important are Psychological Measures to Determine Readiness to Return to Sports after Reconstruction of the Anterior Cruciate Ligament? An Online Survey Study

BACKGROUND

Recent studies have suggested that psychological factors are important components of a successful return to sports (RTS) after anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to survey physicians with respect to their criteria used to determine readiness to RTS after ACLR and to understand the significance of psychological factors on RTS.

METHODS

A survey was designed to understand the practices of clinicians managing rehabilitation after ACLR, consisting of 25 questions divided into 3 different sections, including one section about psychological scores and factors affecting RTS. The survey was delivered to three North American organizations for orthopedic sports medicine.

RESULTS

The total number of respondents was 113. Of the respondents, 95% considered psychological tests at least "somewhat important" (33% "important", 23% selected "very important"). Routine use of psychological tests in practice was only reported by 35% of respondents. The ACL-Return to Sport after Injury Scale was the most frequently used psychological test (23%). Fear of reinjury was considered the most common patient-cited psychological factor affecting RTS. Psychological factors ranked 8th out of 9 outcomes measures in determining readiness to RTS.

CONCLUSION

This study demonstrates a discrepancy between the importance of psychological tests and the frequency of use in practice. Additional education on this topic, web-based applications, and a multidisciplinary approach may increase the usage of psychological tests to determine RTS after ACLR.

Knee Confidence, Fear of Movement, and Psychological Readiness for Sport in Individuals With Knee Conditions: A Systematic Review and Meta-analysis

OBJECTIVES: To (1) compare activity-related psychological factors between individuals with and without knee conditions, and (2) assess associations between these factors and objective measures of function in individuals with knee conditions. DESIGN: A priori registered systematic review with meta-analysis. LITERATURE SEARCH: MEDLINE-Ovid, Embase-Ovid, Scopus-Elsevier, CINAHL-EBSCO, SPORTDiscus-EBSCO, and Cochrane Library were searched to May 27, 2022. STUDY SELECTION CRITERIA: We included peer-reviewed primary data studies (observational and experimental) of human participants with and without knee conditions reporting knee confidence, fear of movement/avoidance beliefs, and/or psychological readiness to return to sport (RTS) or reporting correlations between these factors and objective measures of function in knee conditions. DATA SYNTHESIS: Where possible, data were pooled by knee conditions, otherwise performed narrative syntheses. The Downs and Black checklist assessed the methodological quality of the included studies. RESULTS: Forty studies (3546 participants with knee conditions; 616 participants without knee conditions) were included. There was very low-certainty evidence of higher fear of movement in individuals with knee osteoarthritis (standardized mean difference [SMD], 0.46; 95% confidence interval [CI]: 0.41, 0.52), but not in individuals with patellofemoral pain (SMD, 0.66; 95% CI: -7.98, 9.29) when compared with those without knee conditions. There was very low-certainty evidence of no differences in psychological readiness to RTS after anterior cruciate ligament reconstruction (SMD, -1.14; 95% CI: -2.97, 0.70) compared to no knee condition, and negligible to weak positive correlations between psychological readiness to RTS and objective measures of function. CONCLUSION: There was very low-certainty evidence of higher fear of movement in individuals with knee osteoarthritis compared to those without, and very low-certainty evidence of no correlations between these factors and objective measures of function following anterior cruciate ligament reconstruction. J Orthop Sports Phys Ther 2024;54(4):1-14. Epub 29 January 2024. doi:10.2519/jospt.2024.12070.

Limb asymmetries persist 6 months after anterior cruciate ligament reconstruction according to the results of a jump test battery

Objectives

Test batteries used to assess a patient's return-to-sports (RTS) following anterior cruciate ligament reconstruction (ACLR) are currently undergoing continual development, although no consensus exist on tests to be administered to athletes before allowing return to play. A simple standardized jump test battery was developed to objectively evaluate knee function following ACLR, thereby aiding in RTS decision-making.

Methods

Thirty-three patients who underwent ACLR were prospectively assessed pre-operatively, 6, and 12 months after surgery. Knee function was assessed using a device for optical detection using a test battery consisting of three jump tests: monopodalic countermovement jump (CMJ), drop jump, and monopodalic side-hop. Limb symmetry index (LSI) was reported for all tests at all time points. LSI ≥90% was defined as RTS criteria.

Results

At 12-month evaluation, mean LSI significantly improved compared to 6-month follow up (p < 0.01), and also compared to baseline (p < 0.01), reporting a mean value of 92.6% for CMJ, 90.6 for drop jump and 96.9% for side hop test. Most patients fulfilled the RTS criteria 12 months after surgery (LSI ≥90%). The percentages of patients demonstrating LSI ≥90% at 6 months was 7/33 (21.2%) for CMJ, 12/33 (36.4%) for drop jump, and 11/33 (33.3%) for side-hop test. One year after surgery, percentages grew up to 66.6% (22/33), 63.6% (21/33), and 81.8% (27/33) respectively.

Conclusion

Six months after ACLR, knee functional performance was unsatisfactory in most patients, whereas a significantly higher percentage of patients met RTS criteria 1 year after surgery. The results of the jump test battery proposed in this study support the idea that timing for resumption of cutting and pivoting sports should be delayed later than 6 months, as still limb asymmetries persist at this time point.

Influence of strength and balance ability on functional performance in the involved and uninvolved sides after anterior cruciate ligament reconstruction

BACKGROUND

The restoration and management of the uninvolved side have been emphasized to prevent a second anterior cruciate ligament (ACL) injury and to ensure that athletes return to sports after ACL reconstruction.

OBJECTIVE

To determine the factors influencing the single leg hop test (SLHT) and single leg vertical jump test (SLVJT) at 1 year postoperatively after ACL reconstruction in both the involved and uninvolved sides.

METHODS

Ninety-four patients who underwent ACL reconstruction were assessed at 1 year postoperatively. Multiple regression models included eight independent variables with two dependent variables (SLHT and SLVJT.), each on the involved and uninvolved side.

RESULTS

On the involved side, the Y balance test (YBT), extensor peak torque per body weight (PT/BW), Biodex balance system anteroposterior index (BBS-API), and sex accounted for 53.9% of the variance in SLHT (P= 0.002), and extensor PT/BW and YBT accounted for 26.3% of the variance in SLVJT (P= 0.027). On the uninvolved side, YBT, sex, age, BBS-API, and flexor PT/BW accounted for 47.0% of the variance in SLHT (P= 0.046), and flexor PT/BW, YBT, and age accounted for 44.9% of the variance in SLVJT (P= 0.002).

CONCLUSION

Knee extensor strength on the involved side and flexor strength on the uninvolved side influence the two functional performance tests. The YBT was an important factor in the two functional performance tests in both sides. Anteroposterior stability was the only factor that influenced the SLHT bilaterally.

Anterior Cruciate Ligament Reconstruction Return-to-Sport Decision-Making: A Scoping Review

CONTEXT

Clinical guidelines support the use of testing batteries to assess athlete readiness for return to sport (RTS) and risk of reinjury after anterior cruciate ligament (ACL) reconstruction (ACL-R). There is no consensus on the composition of the testing batteries. Test selection is based mainly on commonality in research, personal preference, and equipment availability. Including athletic performance assessments (APA) used in the athlete's sport may assist RTS decision-making for stakeholders.

OBJECTIVE

To determine whether APA for speed, agility, strength, or cardiovascular endurance are (1) used in ACL-R RTS literature and (2) indicative of RTS or reinjury rates.

DATA SOURCES

A systematic search was performed in MEDLINE, EMBASE, CINAHL, SPORTDiscus, Scopus, Web of Science, and ProQuest Dissertations and Theses Global.

STUDY SELECTION

Eligibility criteria were as follows: (1) athletes between 6 months and 2 years post-ACL-R, (2) commonly used APA, (3) peer-reviewed primary study with original published data.

STUDY DESIGN

Scoping Review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

A total of 17 studies included 24 instances of APA with a high degree of heterogeneity for both tests and protocols.

RESULTS

Agility makes up 75% of the APA. Only 17.6% of studies reported RTS or reinjury rates, none of which reported a significant relationship between these rates and APA outcomes.

CONCLUSION

Speed, strength, and cardiovascular endurance tests are underrepresented in ACL-R RTS literature. Compared with healthy controls, deficits in APA results for ACL-R athletes were common; however, many studies reported significant improvements in results for ACL-R athletes over time. There is some evidence that well-trained ACL-R athletes can match the performance of uninjured athletes in high-level sports.

Functional performance tests, clinical measurements, and patient-reported outcome measures do not correlate as outcomes 1 year after anterior cruciate ligament reconstruction

PURPOSE

The results after anterior cruciate ligament reconstruction (ACLR) are evaluated by laxity measures, functional tests, and patients' perception by patient-reported outcome measures (PROMs). It is not known, if one of these evaluation instruments is representative or if outcome scores from all must be reported to obtain a full evaluation of the condition. The aim was to study the correlations between these three types of outcomes 1 year after primary ACLR.

METHOD

All adult patients (range 18-45 years) who had an ACLR between 1.1.2019 and 31.12.2021 were offered 1-year follow-up by an independent observer. Preoperative information about knee laxity and peroperative information about the condition of menisci and cartilage were registered. At 1-year follow-up clinical and instrumented knee stability and function assessed by four different hop tests were registered. Patients completed four PROMs (the Subjective International Knee Documentation Committee (IKDC) score, the Knee Numeric-Entity Evaluation Score (KNEES-ACL), the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Lysholm score) and Tegner activity scale and answered anchor questions regarding satisfaction and willingness to repeat the operation.

RESULTS

A total of 190 adults attended the 1-year follow-up and 151 had all assessments. There were only a few positive and weak correlations between performance tests and PROMS and between clinical measurements and PROMS (r = 0.00-0.38), and the majority were of negligible strength. Tegner score had in general the highest correlation (low to moderate). The highest correlation was 0.53 (moderate) between the anchor question about patient satisfaction and Lysholm/IKDC scores. There was no difference in the correlations depending on meniscal condition.

CONCLUSIONS

In ACLR patients there was no clinically relevant correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. Therefore, one type of outcome cannot represent the others. This is an argument for always to include and report all three types of outcomes, and conclusions based on one type of outcome may not be sufficient.

LEVEL OF EVIDENCE

II.

Hop to It! The Relationship Between Hop Tests and The Anterior Cruciate Ligament - Return to Sport Index After Anterior Cruciate Ligament Reconstruction in NCAA Division 1 Collegiate Athletes

Background

Outcomes after anterior cruciate ligament reconstruction (ACLR) may not be optimal, with poor physical and psychological function potentially affecting return to sport (RTS) ability. Understanding the relationship between commonly used hop tests and the Anterior Cruciate Ligament - Return to Sport Index (ACL-RSI) may improve rehabilitation strategies and optimize patient outcomes.

Hypothesis/Purpose

The purpose of this study was to examine the relationship between ACL-RSI scores and limb symmetry index (LSI) for the single hop for distance (SHD), triple hop for distance (THD), crossover hop for distance (CHD), timed 6-meter hop (T6H), and single leg vertical hop (SLVH) in a cohort of National Collegiate Athletic Association (NCAA) Division 1 collegiate athletes after ACLR. The hypothesis was that SLVH LSI would be more highly correlated with ACL-RSI score than all horizontal hop tests.

Study design

Cross-Sectional Study.

Methods

Twenty-one National Collegiate Athletic Association (NCAA) Division 1 collegiate athletes (7 males, 14 females) at 6.62 ± 1.69 months after ACLR were included in this retrospective study. Primary outcomes were ACL-RSI score and LSI for SHD, THD, CHD, T6H, and SLVH. The relationship between ACL-RSI scores and performance on hop tests (LSIs) was evaluated using correlation analysis and step-wise linear regression (p ≤ 0.05).

Results

There were significant correlations found when comparing ACL-RSI and the LSI for SHD (rs = 0.704, p < 0.001), THD (rs = 0.617, p = 0.003), CHD (rs = 0.580, p = 0.006), and SLVH (rs = 0.582, p = 0.006). The CHD explained 66% (R2 value of 0.660) of the variance in the ACL-RSI, while the other hop tests did not add to the predictive model.

Conclusions

Physical function has the capacity to influence psychological status after ACLR. Clinicians should recognize that SLVH, SHD, THD, and CHD are correlated with ACL-RSI and improvements in physical function during rehabilitation may improve psychological status and optimize RTS after ACLR.

Level of evidence

Level 3.

Therapy-based expert system on function and postural stability after anterior cruciate ligament reconstruction: a pilot study

PURPOSE

Wii Fit exergames have been less commonly used for the rehabilitation of athletes after Anterior Cruciate Ligament Reconstruction (ACLR). This study aims to investigate the effects of an expert system using Wii Fit exergames compared to conventional rehabilitation following ACLR. A forward-chaining rule-based expert system was developed which proposed a rehabilitation program that included the number and type of exercise in terms of difficulty and ease and the duration of each exercise in a progressive manner according to the patient's physical condition.

MATERIALS AND METHODS

Twenty eligible athletes aged 20-30 who underwent ACLR were enrolled in this study and randomly assigned to two groups; and received 12 sessions of either Wii Fit exergames as Wii group (n = 10) or conventional rehabilitation as CL group (n = 10).

RESULTS

The main outcomes consisted of pain (Visual Analogue Scale (VAS)), knee effusion, knee flexion range (KFR), thigh girth (TG), single-leg hop for distance (SLHD), and for time (SLHT), static and dynamic balance tests. Both groups had considerable improvement in all outcomes, also there were significantly differences between Wii and CL groups as follows; VAS (P < 0.001), knee effusion (P < 0.001), TG (P = 0.001), KFR (P = 0.012), static balance in stable position (P < 0.001) and in unstable position (P = 0.001), dynamic balance in the anterior (P < 0.001), posteromedial (P < 0.001), posterolateral (P = 0.004) directions, symmetry index of SLHD (P < 0.001) and symmetry index of SLHT (P = 0.013).

CONCLUSIONS

The findings showed that using Wii Fit exergames in post-ACLR patients reduced pain and effusion while also improving function and balance significantly. Iranian Registry of Clinical Trials registration number is IRCT20191013045090N1, and the registration date is 03-03-2020.

Drop Jump Performance Improves One Year Following Anterior Cruciate Ligament Reconstruction in Sportsmen Irrespectively of Psychological Patient Reported Outcomes

Our study aims to prospectively report the functional outcomes of 31 sportsmen following anterior cruciate ligament (ACL) reconstruction, up to 12 months after surgery, with regards to subjective tests and drop jump performance, and to investigate the correlations between these variables, to be used for determining the return to sports after ACL reconstruction. Lysholm score, Tegner activity level, and the ACL-Return to Sport after Injury (ACL-RSI) scale were evaluated preoperatively, at 6 months, and at 12 months after surgery. Drop vertical jump was recorded using an infrared optical acquisition system. Lysholm and ACL-RSI scores significantly improved at the 12-month follow-up compared to the baseline and 6-month evaluations (p < 0.001). Concerning Tegner activity level, no statistically significant differences were reported between pre- and post-operative status (p = 0.179). Drop jump limb symmetry index significantly improved at 12 months, with the mean value improving from 76.6% (SD: 32,4) pre-operatively to 90.2% (SD: 14.7; p < 0.001) at follow-up. Scarce positive correlation was reported between the ability to perform drop jumps and activity level in athletes one year after ACL reconstruction. In addition, subjective knee score and psychological readiness were not related to jumping performance.

Dynamic valgus knee revealed with single leg jump tests in soccer players

BACKGROUND

Dynamic valgus knee occurs in sports that involve jumps and landing such as soccer and pose an increased risk for anterior cruciate ligament injury. Visual estimation is biased by the athlete's body type, the experience of the evaluator and the movement phase at which the valgus is assessed - thus the result is highly variable. The aim of our study was to accurately assess dynamic knee positions during single and double leg tests through a video-based movement analysis system.

METHODS

Young soccer players (U15, N.=22) performed single leg squat, single leg jump, and double leg jump tests while the knee medio-lateral movement was monitored with a Kinect Azure camera. Jumping and landing phases of the movement were determined within the continuous recording of the knee medio-lateral position over the ankle and the hip vertical position. Kinect measurements were validated by Optojump (Microgate, Bolzano, Italy).

RESULTS

Soccer players retained their predominantly varus knee positions in all phases of double-leg jumps, which was far less prominent in single leg tests. Interestingly, a marked dynamic valgus was observed in athletes who participated in traditional strengthening exercises, while this valgus shift was mostly prevented in those who participated in antivalgus training regimes. All these differences were only revealed during single leg tests, while the double leg jump tests masked all valgus tendencies.

CONCLUSIONS

We propose to use single-leg tests and movement analysis systems for evaluating dynamic valgus knee in athletes. These methods can reveal valgus tendencies even in soccer players who have a characteristic varus knee while standing.

Isolated lateral extra-articular tenodesis in ACL-deficient knees: in vivo knee kinematics and clinical outcomes

PURPOSE

To carry out an in vivo kinematic analysis of isolated modified Lemaire lateral extra-articular tenodesis (LET) to explore its ability to modify the stability of anterior cruciate ligament (ACL) deficient knees. The secondary aim was to look at the clinical outcomes of the isolated LET to analyze whether biomechanical changes have an influence on clinical improvement or not.

METHODS

A total of 52 patients who underwent an isolated modified Lemaire LET were prospectively studied. Twenty-two were over 55-year-old patients with ACL rupture and subjective instability (group 1). They were followed up for 2 years postoperatively. Thirty were patients underwent a two-stage ACL revision (group 2). They were followed up for 4 months postoperatively (up to the second stage of the ACL revision). Preoperative, intraoperative, and postoperative kinematic analyses were carried out using the KiRA accelerometer and KT1000 arthrometer to look for residual anterolateral rotational instability and residual anteroposterior instability. Functional outcomes were measured with the single-leg vertical jump test (SLVJT) and the single-leg hop test (SLHT). Clinical outcomes were evaluated using the IKDC 2000, Lysholm, and Tegner scores.

RESULTS

A significant reduction of both rotational and anteroposterior instability was detected. It was present both with the patient under anesthesia (p < 0.001 and p = 0.007 respectively) as well as with the patient awake (p = 0.008 and p = 0.018 respectively). Postoperative analysis of knee laxity did not show any significant variation from the first to the last follow-up. Both the SLVJT and SLHT improved significantly at the last follow-up (p < 0.001 and p = 0.011 respectively). The mean values of both the IKDC and Lysholm and Tegner scores showed an improvement (p = 0.008; p = 0.012; p < 0.001).

CONCLUSION

The modified Lemaire LET improves the kinematics of ACL-deficient knees. The improvement in the kinematics leads to an improvement in subjective stability as well as in the function of the knee and in the clinical outcomes. At the 2-year follow-up, these improvements were maintained in a cohort of patients over 55 years. Following our findings, to reduce knee instability, an isolated LET in ACL-deficient knees may be used when ACL reconstruction in patients over 55 years is not indicated.

LEVEL OF EVIDENCE

Level IV.

Correlation of Y Balance with Clinical Scores and Functional Tests after Anterior Cruciate Ligament Reconstruction in Young and Middle-Aged Patients

Background

Criteria for return to sports (RTS) following anterior cruciate ligament (ACL) reconstruction have been extensively studied. But there is no consensus among investigators regarding which factors are most important in determining a safe RTS.

Methods

Sixty-one patients who underwent ACL reconstruction were included. Subjective knee scoring systems (International Knee Documentation Committee [IKDC] score and Lysholm score), functional performance tests (carioca test and single-leg hop for distance [SLHD] test), and isokinetic knee strength test were used for assessment and analyzed for association with the limb symmetry index (LSI) of the Y-balance test for lower quarter (YBT-LQ).

Results

The LSI of the YBT-LQ was significantly correlated with Lysholm score, IKDC score, Carioca, LSI for the SLHD, and extensor strength deficit at 6 months after ACL reconstruction. At 12 months, Lysholm score, IKDC score, LSI for the SLHD, and extensor strength deficit were significantly correlated with the LSI of the YBT-LQ.

Conclusions

The YBT-LQ test could be used conveniently as an additional tool to assess the patient's functional performance results after ACL reconstruction in outpatient clinics.

No correlation between performance tests, clinical measurements and data from patient-reported outcome measures (PROM) in children reconstructed for anterior cruciate ligament injury

PURPOSE

To investigate if patient-reported outcome measures (PROMs), functional tests and clinical measures correlate well in children after reconstruction of the anterior cruciate ligament (ACL). It was hypothesized that these outcomes correlate, so it is sufficient to report only one of them.

METHODS

A consecutive group of children (< 16 years old) who had an ACL reconstruction, were prospectively followed and assessed after 1-year with Pedi-IKDC and KOOS-Child, instrumented laxity measurement, range of motion, extension strength and four performance tests. Relations between the different outcomes were calculated by partial correlation coefficient analysis, controlling for gender, age, height, and weight.

RESULTS

Outcomes were available for 141 of 163 children. There were only few positive and weak correlations between performance tests and PROM scores and between clinical measurements and PROM scores. There were weak to strong correlations between the scores from Pedi-IKDC and the scores from each of the five domains of KOOS-Child and a weak to moderate correlation between the different domains of KOOS-Child. Similar correlations were found between the different performance tests.

CONCLUSION

For children who had their ACL reconstructed there was no clinically important correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. This is an argument for always to include and report all three types of outcomes.

LEVEL OF EVIDENCE

Level II.

Measurement properties for muscle strength tests following anterior cruciate ligament and/or meniscus injury: What tests to use and where do we need to go? A systematic review with meta-analyses for the OPTIKNEE consensus

Objectives

Critically appraise and summarise the measurement properties of knee muscle strength tests after anterior cruciate ligament (ACL) and/or meniscus injury using the COnsensus-based Standards for the selection of health Measurement INstruments Risk of Bias checklist.

Design

Systematic review with meta-analyses. The modified Grading of Recommendations Assessment, Development and Evaluation-guided assessment of evidence quality.

Data sources

Medline, Embase, CINAHL and SPORTSDiscus searched from inception to 5 May 2022.

Eligibility criteria for selecting studies

Studies evaluating knee extensor or flexor strength test reliability, measurement error, validity, responsiveness or interpretability in individuals with ACL and/or meniscus injuries with a mean injury age of ≤30 years.

Results

Thirty-six studies were included involving 31 different muscle strength tests (mode and equipment) in individuals following an ACL injury and/or an isolated meniscus injury. Strength tests were assessed for reliability (n=8), measurement error (n=7), construct validity (n=27) and criterion validity (n=7). Isokinetic concentric extensor and flexor strength tests were the best rated with sufficient intrarater reliability (very low evidence quality) and construct validity (moderate evidence quality). Isotonic extensor and flexor strength tests showed sufficient criterion validity, while isometric extensor strength tests had insufficient construct and criterion validity (high evidence quality).

Conclusion

Knee extensor and flexor strength tests of individuals with ACL and/or meniscus injury lack evidence supporting their measurement properties. There is an urgent need for high-quality studies on these measurement properties. Until then, isokinetic concentric strength tests are most recommended, with isotonic strength tests a good alternative.

Reactive strength index during single-limb vertical continuous jumps after anterior cruciate ligament reconstruction: cross-sectional study

BACKGROUND

The association of the reactive strength index (RSI) during single-limb vertical continuous jumps (SVCJs) with single-limb hop tests in athletes after anterior cruciate ligament reconstruction (ACLR) is unclear. Thus, this study aimed to confirm the measurement properties of the RSI during SVCJs in athletes with ACLR at the phase of determining the timing of their return to sport.

METHODS

RSI during SVCJs and single-limb hop (single, triple, and crossover) tests were measured for post-ACLR and healthy athletes. The limb symmetry index (LSI) was calculated using the measurements of each parameter. For each test, patients were divided into two subgroups according to their LSI score (≥ 90%, satisfactory; < 90%, unsatisfactory). Fisher's exact test was used to examine the association of single-limb hop tests with RSI during the SVCJs.

RESULTS

A total of 21 post-ACLR and 17 healthy athletes completed all the tests. RSI during SVCJs was significantly lower on the involved limb than on the uninvolved limb in post-ACLR athletes (P < 0.001). The LSI of RSI during SVCJs of post-ACLR athletes was significantly lower than that of the healthy athletes (P < 0.01). Among the post-ACLR athletes, < 30% of those with LSIs > 90% in the single-limb hop tests had an LSI > 90% of the RSI during SVCJs.

CONCLUSIONS

RSI during SVCJs of post-ACLR athletes was significantly lower on the involved limb than on the uninvolved limb, and the asymmetry was more remarkable in the SVCJs than in the single-limb hop tests.

What tests should be used to assess functional performance in youth and young adults following anterior cruciate ligament or meniscal injury? A systematic review of measurement properties for the OPTIKNEE consensus

OBJECTIVES

To critically appraise and summarise measurement properties of functional performance tests in individuals following anterior cruciate ligament (ACL) or meniscal injury.

DESIGN

Systematic review.

DATA SOURCES

Systematic searches were performed in Medline (Ovid), Embase (Ovid), CINAHL (EBSCO) and SPORTSDiscus (EBSCO) on 7 July 2021.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies evaluating at least one measurement property of a functional performance test including individuals following an ACL tear or meniscal injury with a mean injury age of ≤30 years. The COnsensus-based Standards for the selection of health Measurement INstruments Risk of Bias checklist was used to assess methodological quality. A modified Grading of Recommendations Assessment, Development and Evaluation assessed evidence quality.

RESULTS

Thirty studies evaluating 26 functional performance tests following ACL injury were included. No studies were found in individuals with an isolated meniscal injury. Included studies evaluated reliability (n=5), measurement error (n=3), construct validity (n=26), structural validity (n=1) and responsiveness (n=1). The Single Leg Hop and Crossover Hop tests showed sufficient intrarater reliability (high and moderate quality evidence, respectively), construct validity (low-quality and moderate-quality evidence, respectively) and responsiveness (low-quality evidence).

CONCLUSION

Frequently used functional performance tests for individuals with ACL or meniscal injury lack evidence supporting their measurement properties. The Single Leg Hop and Crossover Hop are currently the most promising tests following ACL injury. High-quality studies are required to facilitate stronger recommendations of performance-based outcomes following ACL or meniscal injury.

Lateral extraarticular tenodesis improves stability in non-anatomic ACL reconstructed knees: in vivo kinematic analysis

PURPOSE

To carry out an in vivo kinematic analysis to determine whether adding a lateral extraarticular tenodesis (LET) for those patients with subjective instability and objective residual laxity after a transtibial (TT) anterior cruciate ligament reconstruction (ACLR) reduces anteroposterior and rotational laxity and to evaluate the 2-year follow-up clinical outcomes to analyze whether biomechanical changes determine clinical improvement or not.

METHODS

A total of 19 patients with residual knee instability after TT ACLR who underwent a modified Lemaire LET were prospectively evaluated for at least 2-year follow-up. Preoperative, intraoperative, and 6 and 24-month postoperative kinematic analyses were carried out using the KiRA accelerometer and KT1000 arthrometer to look for residual anterolateral rotational instability and residual anteroposterior instability. Functional outcomes were measured with the single-leg vertical jump test and the single-leg hop test. Clinical outcomes were evaluated using the IKDC 2000, Lysholm, and Tegner scores.

RESULTS

A significant reduction in anterolateral rotational instability was detected with the patient under anesthesia (from 3 ± 1.2 to 1.1 ± 1.1 m/s²; p < 0.05) as well as with the patient awake (from 2.1 ± 0.8 to 0.7 ± 1.4 m/s²; p < 0.05). A significant reduction in anteroposterior instability was only present under anesthesia (from 3.4 ± 1.9 to 2.1 ± 1.1 mm; p < 0.05), while no difference was present without anesthesia (from 2.3 ± 1.1 to 1.6 ± 1 mm; n.s.). Postoperative analysis of knee laxity did not show any significant variation from the first to the last follow-up. Both the single-leg vertical jump test and single-leg hop test improved significantly at the last follow-up (both p < 0.05). The mean values of both the IKDC and Tegner scores showed an improvement (p < 0.05 and p < 0.05, respectively), whereas that was not the case with the Lysholm score (n.s.).

CONCLUSIONS

The modified Lemaire LET can improve the kinematics of a non-anatomic ACL reconstructed knee with residual subjective and objective instability. These kinematic changes were able to lead to an improvement in subjective stability as well as the function of the knee in a small cohort of recreationally active patients. At 2-year follow-up, the kinematic changes as well as the level of activity of the patients and the IKDC score show their improvement sustained.

LEVEL OF EVIDENCE

Level IV.

Patients with advanced lateral osteoarthritis can return to sports and work after distraction arthroplasty plus lateral meniscal allograft transplantation combined with cartilage repair

PURPOSE

This study aimed to report return to sports (RTS) and return to work (RTW) outcomes after distraction arthroplasty (DA) plus lateral meniscal allograft transplantation (MAT) combined with cartilage repair in active patients with advanced osteoarthritis. It was hypothesised that DA combined with lateral MAT would improve clinical and radiological outcomes and enable RTS and RTW for most patients.

METHODS

In total, 21 patients with advanced osteoarthritis (moderate to severe joint space narrowing at lateral edge on Rosenberg view and large cartilage defect of lateral femoral condyle) who underwent concomitant DA and MAT were retrospectively reviewed. Clinical outcomes were assessed using subjective knee scores [Lysholm score, International Knee Documentation Committee (IKDC) subjective knee score, and Tegner activity scale (TAS)] and functional tests (isokinetic extensor muscle strength test, single-leg vertical jump test, and single-leg hop for distance test). The rates of RTS, RTW, and satisfaction were evaluated. Radiological outcomes were assessed using magnetic resonance imaging (MRI) and X-ray (Rosenberg view).

RESULTS

The mean age at surgery and mean follow-up duration were 37.2 ± 5.9 years and 37.1 ± 5.4 months, respectively. All improvements in subjective scores were statistically significant (p < 0.001). The Lysholm score improved from 58.3 ± 8.1 to 84.3 ± 8.2, the IKDC subjective score from 53.9 ± 10.4 to 78.0 ± 7.7, and the TAS from 4.0 ± 0.5 to 5.1 ± 0.8. The limb symmetry index (LSI) (%) of the extensor peak torque at an angular velocity of 60°/s improved from 67.3 ± 19.2 to 88.4 ± 20.3% (p = 0.001). The LSI of the single-leg vertical jump test and single-leg hop for distance test improved from 62.8 ± 21.3 to 87.7 ± 19.5% and from 63.9 ± 20.8 to 85.5 ± 18.1%, respectively (all, p < 0.001). All patients were able to return to any sports activity and work. However, 67% and 90.5% returned to their defined or desired level of sports activity and occupation intensity, respectively. Further, 76.2% were very satisfied or somewhat satisfied with the outcome at the last follow-up. The JSW increased by 0.8 ± 0.4 to 2.3 ± 0.6 mm (p = 0.005). In more than 90% of patients, > 50% of cartilage lesion was covered. The mean graft extrusion was 2.6 ± 1.0 mm.

CONCLUSION

All patients who underwent distraction arthroplasty plus lateral MAT combined with cartilage repair returned to any sports and work at the last follow-up. Significant improvements in clinical outcomes and the radiographic joint space width were observed. However, the activity ability was somewhat reduced compared with the best preoperative level. This one-stage joint salvage treatment is a promising option for young and active patients with advanced OA who wish to return to high levels of sports activity and occupation intensity (≥ Tegner activity scale 4).

LEVEL OF EVIDENCE

III.

Foot tapping and unilateral vertical jump performance in athletes after knee surgery: an explorative cross-sectional study

Background

Guiding athletes through the rehabilitation process and judging the time at which return to sports can be enabled after anterior cruciate ligament (ACL) injuries are still challenging processes. The purpose of this explorative cross-sectional study was to retrospectively compare unilateral vertical jump as well as vertical foot tapping outcomes in athletes returned to sports after ACL reconstruction (ACLR) with uninjured athletes.

Methods

Seven-teen ACLR athletes (male/female: 12/5) were examined 11 (6–23) months after their ACL injury and after return to sport clearance together with 67 uninjured athletes (male/female: 51/16). Seventeen age and stature matched controls were selected from the sample of uninjured athletes. Participants unilaterally performed acyclic (squat jump, SJ; drop jump, DJ) and cyclic (foot tapping, FT) tests. SJ peak power, DJ take-off efficiency (TOE) and FT coefficients (FTC) were compared between ACLR and matched as well as unmatched control groups. Limb symmetry index (LSI) as well as performance score were calculated.

Results

Analyses of the SJ peak power revealed moderate effects of group (right: P < 0.09, η_p² = 0.06; left: P < 0.05, η_p² = 0.08). The TOE was largely affected by group (right: P < 0.01, η_p² = 0.12; left: P < 0.01, η_p² = 0.13). No effect of group was found on the FTC (P > 0.8, η_p² < 0.01). The SJ peak power LSI (r = 0.46, P < 0.07) and TOE LSI (r = 0.38, P = 0.13) were positively associated with the performance score of the ACLR group.

Conclusion

Although already returned to sports, the ACLR group underperformed the matched and unmatched control groups significantly. Unilaterally performed vertical jumps may provide additional information on athletes’ rehabilitation progress and help to manage the rehabilitation process and decisions on potential readiness after ACLR. More attention should be paid to the direction of the LSI results.

On-Field Tests for Patients After Anterior Cruciate Ligament Reconstruction: A Scoping Review

Background:

After anterior cruciate ligament reconstruction (ACLR), a patient’s physical capacities, such as (repeated) sprint performance, agility performance, and intermittent endurance performance, are often reduced because of detraining effects. Monitoring the progression of these physical capacities is essential for specific training goals before patients return to complex team sports.

Purpose:

To map the existing literature regarding on-field tests for (repeated) sprint performance, agility performance, and intermittent endurance performance in patients after ACLR.

Study Design:

Scoping review; Level of evidence, 4.

Methods:

A search was performed in 4 electronic databases, PubMed, Embase, CINAHL, and PsycInfo, following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for scoping reviews.

Results:

There were 11 studies that met the inclusion criteria and described a total of 14 on-field tests for patients after ACLR. Overall, 2 tests were described for sprint performance, 11 tests were related to agility performance, and 1 test was performed for intermittent endurance performance.

Conclusion:

The results of this scoping review provide an overview of on-field tests to monitor sport-specific progression and to set performance-specific training goals for patients after ACLR before returning to complex team sports.

Limb preference impacts single-leg forward hop limb symmetry index values following ACL reconstruction

Following anterior cruciate ligament (ACL) reconstruction limb dominance for performing tasks is not considered when making rehabilitation progression decisions. The purpose of this study was to determine if strength and functional outcomes differ between individuals who injured their preferred or nonpreferred jumping limb and to determine if these same outcomes differ between individuals who injured their preferred or nonpreferred limb used to kick a ball. A secondary purpose was to determine the association of quadriceps strength and single-leg forward hop performance with patient self-reported function. Forty individuals with ACL reconstruction (age = 20.0 ± 4.6 years, height = 174.2 ± 12.7 cm, mass = 71.2 ± 12.7 kg, time since surgery = 5.3 ± 0.8 months) were included in the study. Primary outcome measures included, International Knee Documentation Committee Subjective Knee Form (IKDC) scores, quadriceps limb symmetry index (LSI) values, and single-leg forward hop LSI values. Limb preference was defined two ways, kicking a ball and performing a unilateral jump. There were no significant differences between groups based on injury to the preferred limb to kick a ball for any of the outcome variables. Individuals who injured their nonpreferred jumping limb demonstrated significantly (p = 0.05, d = 0.77) lower single-leg forward hop LSI values (81.1% ± 19.5%) compared to individuals who injured their preferred jumping limb (94.1% ± 12.6%), but demonstrated no differences in IKDC scores or quadriceps LSI values. Quadriceps LSI and single-leg forward hop LSI explained 73% of the variance in IKDC scores, but quadriceps LSI had the strongest association (r = 0.790). These findings suggests that limb preference influences single forward hop LSI values and should be considered following ACL reconstruction.

Single-Leg Vertical Hop Test Detects Greater Limb Asymmetries Than Horizontal Hop Tests After Anterior Cruciate Ligament Reconstruction in NCAA Division 1 Collegiate Athletes

BACKGROUND

Knee function deficits may persist after anterior cruciate ligament reconstruction (ACLR). Return to sport (RTS) testing batteries assess recovery after ACLR and can guide RTS progression, but the ideal test components are debatable. The single leg vertical hop for height (SLVH) test using a commercially available jump mat may provide a valuable assessment of knee function.

HYPOTHESIS/PURPOSE

The purpose of this study was to compare the limb symmetry index (LSI) of SLVH to horizontal hop testing in a cohort of National Collegiate Athletic Association (NCAA) Division 1 collegiate athletes after ACLR. The hypothesis was the SLVH would elicit significantly lower LSI than horizontal hop tests.

STUDY DESIGN

Cross-Sectional Study.

METHODS

Eighteen National Collegiate Athletic Association (NCAA) Division 1 collegiate athletes (7 males, 11 females) at 7.33 ± 2.05 months after ACLR were included in this retrospective study. LSI was calculated for single hop for distance (SHD), triple hop for distance (THD), cross-over hop for distance (CHD), timed 6-meter hop (T6H), and SLVH. A repeated measures ANOVA was performed to identify differences in LSI for each test. Spearman's Rho correlation coefficient was calculated to examine the relationship between LSIs for each test.

RESULTS

The LSI for SLVH (84.48% ± 11.41%) was significantly lower than LSI for SHD (95.48 ± 8.02%, p = 0.003), THD (94.40 ± 3.70%, p = 0.002), CHD (95.85 ± 7.00, p = 0.007), and T6H (97.69 ± 6.60%, p = 0.001). The correlation of LSI between SLVH and the horizontal hop tests was weak and non-significant for SHD (rs = 0.166, p = 0.509), CHD (rs = 0.199, p = 0.428), and T6H (rs = 0.211, p = 0.401) and moderate and non-significant for THD (rs = 0.405, p = 0.096).

CONCLUSIONS

Individuals after ACLR had lower LSI on the SLVH than on horizontal hop tests and weak to moderate correlations between the tests suggest SLVH detects performance deficits not identified by the horizontal hop tests.

LEVEL OF EVIDENCE

3.

Reintroduction of running after ACL reconstruction with a hamstring graft: can we predict short-term success?

CONTEXT

Return to running (RTR) after anterior cruciate ligament reconstruction (ACL-R) is a crucial milestone. However, there is uncertainty on how and when to start a running program.

OBJECTIVE

To explore the feasibility of a structured program to reintroduce running after ACL-R and to evaluate the predictive value of potential predictors of short-term success.

DESIGN

Longitudinal cohort study.

SETTING

Local Research Center / participant's home.

PATIENTS

Thirty-five participants were recruited after ACL-R.

INTERVENTION

Program with a progression algorithm to reintroduce running (10 running sessions in 14 days).

MAIN OUTCOME MEASURES

The criterion for short-term success was no exacerbation of symptoms. Potential predictors included: (i) the International Knee Document Committee (IKDC) subjective knee form; (ii) ACL Return to Sport after Injury questionnaire; (iii) quadriceps and hamstring strength; (iv) Step-Down Endurance test; and (v) the modified Star Excursion Balance test. Descriptive statistics were performed to study the feasibility of the RTR program and Poisson regression analysis was used to evaluate predictors of success.

RESULTS

Of the 34 participants included, 33 completed the RTR program. Sixteen participants experienced some temporary exacerbation of symptoms, but only one had to stop the RTR program. Initial IKDC score was the only significant predictor of a successful RTR with an Area under the ROC curve of 80.4%. An ICKD cut-off of 63.7/100 differentiated responders and non-responders with the highest sensitivity and specificity (77.8% and 75.0%, respectively). There was a 3-fold greater chance of success with an IKDC score above this threshold.

CONCLUSIONS

Our results confirm the feasibility of our RTR program and progression algorithm after ACL-R. Clinicians should use an IKDC score of >64 as a criterion to reintroduce running after ACL-R to increase the likelihood of short-term success.

Comparison of Different Functional Tests for Leg Power and Normative Bilateral Asymmetry Index in Healthy Collegiate Athletes

Background

Bilateral leg power is being increasingly investigated as a proxy for the recovery of muscle performance after injury. Functional tests like the single leg hop for distance (SLHD) and single leg vertical jump (SLVJ) are often used to determine symmetry and return to play (RTP) readiness. As an injury predictor, leg power is accurately measured with the Keiser Air420 seated leg press.

Purpose

To measure and analyze lower leg asymmetry in healthy collegiate athletes across each test battery.

Methods

Eighty-eight healthy student-athletes (44 males, 44 females) across 14 varsity teams at Wake Forest University performed the SLHD, SLVJ, and the Keiser. Horizontal and vertical displacement were measured via the SLHD and SLVJ, respectively. Peak power was recorded via the Keiser Air420 leg press. Pearson correlations and repeated measures ANOVA were used to calculate associations and compare bilateral asymmetry indices (BAI) and raw scores.

Results

There was a significant effect on each test’s raw BAI (P < 0.01). The mean absolute BAI were 5.42 ± 4.9%, 6.64 ± 4.9% and 5.36 ± 4.7% for the SLHD, SLVJ and Keiser, respectively. The SLVJ and Keiser (dominant leg r = 0.832, nondominant leg r = 0.826) were more highly correlated than the SLHD and Keiser (dominant leg r = 0.645, nondominant leg r = 0.687), all of which were statistically significant (P < 0.01).

Conclusion

At the 90th percentile, healthy collegiate athletes attained <15% BAI. We recommend the implementation of a battery of tests to determine normative lower limb asymmetry. A battery of functional tests may present different asymmetry indices as opposed the 10% reference asymmetry.

Neural Mobilization Short-Term Dose Effect on the Lower-Limb Flexibility and Performance in Basketball Athletes: A Randomized, Parallel, and Single-Blinded Study

CONTEXT

Neural mobilization is commonly used in sports, and previous studies have suggested that it has a positive impact on lower-limb flexibility and performance. However, studies exploring the effect of neural mobilization dosage are almost nonexistent.

OBJECTIVES

This study aimed to assess whether 2 distinct dosages of neural gliding mobilization (4 and 8 sets of 10 repetitions) impact the flexibility and performance of both the mobilized and nonmobilized lower limb in basketball athletes differently.

DESIGN

Randomized, parallel, and single-blinded study.

SETTING

Amateur and professional basketball clubs.

PARTICIPANTS

Fifty-two basketball athletes (40 men and 12 women), who were distributed into 2 groups; one received 40 (n = 28) and the other 80 repetitions (n = 24) of neural gliding mobilization.

INTERVENTION

Neural gliding mobilization applied to a single limb (the dominant limb).

MAIN OUTCOME MEASURES

Knee extension angle for hamstring flexibility; hop tests and single-leg vertical jump for performance.

RESULTS

There was a significant main effect of time (P < .001), a significant interaction between time and limb for flexibility (P = .003), and a significant interaction between time and limb for the single-leg hop test (P = .032). No other significant main effect for any of the remaining variables was found (P > .05).

CONCLUSIONS

The application of both 40 repetitions and 80 of neural gliding significantly improved lower-limb flexibility, and one was not superior to the other. Neither one dosage nor the other positively or negatively impacted the lower-limb performance of basketball athletes.

Test Batteries After Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review

CONTEXT

There is a lack of consensus regarding test batteries for return to sport (RTS) after anterior cruciate ligament reconstruction (ACLR).

OBJECTIVE

To report the RTS test batteries for individuals after ACLR and to examine alignment with the American Academy of Orthopaedic Surgeons (AAOS) Appropriate Use Criteria (AUC). Finally, to examine how published RTS batteries prior to the AAOS AUC (2010-2015) compared with those after publication of the AUC (2016-2020).

DATA SOURCE

A systematic search of PubMed (2010-2020).

STUDY SELECTION

Studies were included if they were published from 2010 to 2020, patients underwent primary ACLR and were tested between 6 months and 2 years postoperatively and included a minimum of 2 assessments. Studies were excluded if patients were tested outside the designated time; had undergone a revision, contralateral, or multiligament injury; included healthy participants; were level 5 evidence or the study was a systematic review. A total of 1012 articles were reviewed and 63 met the criteria.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Information regarding the RTS batteries and patient demographics were extracted from the included articles.

RESULTS

A total of 63 studies met the inclusion and exclusion criteria (22 from 2010-2015 and 41 from 2016-2020). The most common RTS batteries included the hop test, quadriceps strength test, and patient-reported outcome measures. No study met all 7 AUC; the most common criteria met were functional skills (98.4%), followed by confidence (22.2%), then range of motion and knee stability (20.6%).

CONCLUSION

The test batteries in the current literature show high variability and a lack of essential components necessary for RTS. No study met the AUC guidelines, suggesting a disconnect between recommended guidelines and clinical practice. Test battery research has expanded over the past decade; however, standardized, clinically applicable batteries that encompass all criteria are needed.

Is It Time We Better Understood the Tests We are Using for Return to Sport Decision Making Following ACL Reconstruction? A Critical Review of the Hop Tests

There has been a move towards a criterion-based return to play in recent years, with 4 single-leg hop tests commonly used to assess functional performance. Despite their widespread integration, research indicates that relationships between ‘passing’ ‘hop test criteria and successful outcomes following rehabilitation are equivocal, and, therefore, require further investigation. This critical review includes key information to examine the evolution of these tests, their reliability, relationships with other constructs, and sensitivity to change over time. Recommendations for how measurement and administration of the tests can be improved are also discussed. The evidence presented in this review shows that hop tests display good reliability and are sensitive to change over time. However, the use of more than 2 hop tests does not appear to be necessary due to high collinearity and no greater sensitivity to detect abnormality. The inclusion of other hop tests in different planes may give greater information about the current function of the knee, particularly when measured over time using both relative and absolute measures of performance. It is recommended that the contralateral limb be tested prior to surgery for a more relevant benchmark for performance, and clinicians are strongly advised to measure movement quality, as hop distance alone appears to overestimate the recovery of the knee.

Interrater and Intrarater Reliability and Discriminant Validity of a Pediatric Lower Extremity Physical Therapy Clearance Test

Background:

Few studies have validated when an athlete can safely return to sports, and even fewer have identified when he or she no longer requires physical therapy after surgery. Discontinuing physical therapy is often dictated by insurance restrictions, but most studies have suggested that the decision should be multifactorial, stemming from patient-derived subjective outcome questionnaires, clinical examination, and isokinetic and functional testing.

Purpose/Hypothesis:

The purpose of this study was to establish discriminant validity and reliability of an objective physical therapy clearance (PTC) test in a clinical setting. The hypotheses were that the PTC test (1) will demonstrate different scores between normal and postoperative cohorts and (2) will have acceptable inter- and intraobserver reliability.

Study Design:

Cohort study (diagnosis); Level of evidence, 3.

Methods:

Four cohorts (27 total participants; age range, 12-18 years) underwent the PTC test: 9 adolescents 6 months after anterior cruciate ligament reconstruction, 4 adolescents 6 weeks after partial meniscectomy, 5 adolescents with nonstructural knee pain, and 9 control/healthy participants without any lower extremity complaint. The PTC test included a dynamic warm-up, objective measures (knee range of motion, thigh girth, and muscle motor tone), functional strength tests (heel raises, single-leg dips, hop tests, tuck jumps), and agility tests (shuffle and sprint T-test). Each testing session was videotaped and scored live by the physical therapist administering the test, and then scored via the video recording by an independent physical therapist and 2 orthopaedic surgeons.

Results:

The PTC test was found to have discriminant validity between the control cohort and both cohorts with previous surgery. The single-leg dip, single-leg hop, and vertical tuck jump were the most discriminatory components. The PTC test had moderate to almost perfect intrarater reliability (κ = 0.57-1), but only fair to moderate interrater reliability among video graders (κ = 0.29-0.58) and slight to substantial reliability between video graders and the live PT rater (κ = 0.19-0.63).

Conclusion:

The PTC test was found to have moderate inter- and intraobserver agreement, with the ability to discriminate between postoperative and control patients.

Strength and Power Training in Rehabilitation: Underpinning Principles and Practical Strategies to Return Athletes to High Performance

Injuries have a detrimental impact on team and individual athletic performance. Deficits in maximal strength, rate of force development (RFD), and reactive strength are commonly reported following several musculoskeletal injuries. This article first examines the available literature to identify common deficits in fundamental physical qualities following injury, specifically strength, rate of force development and reactive strength. Secondly, evidence-based strategies to target a resolution of these residual deficits will be discussed to reduce the risk of future injury. Examples to enhance practical application and training programmes have also been provided to show how these can be addressed.

Current clinical practice and return-to-sport criteria after anterior cruciate ligament reconstruction: a survey of Brazilian physical therapists

BACKGROUND

Adherence to the use of recommended measures/criteria for return to sport clearance after anterior cruciate ligament reconstruction is crucial for successful rehabilitation.

OBJECTIVES

The purpose of this study was to describe the current clinical practice of Brazilian physical therapists that treat patients after anterior cruciate ligament reconstruction, including the measures/criteria used to support the decision-making process regarding return to sport. The secondary aim was to investigate factors associated with the use of the most recommended measures/criteria for return to sport.

METHODS

An electronic survey questionnaire was sent to Brazilian physical therapists. The survey consisted of questions about demographics and professional and clinical practice data related to anterior cruciate ligament reconstruction postoperative rehabilitation and return to sport criteria. Descriptive statistics and chi-square tests were used for analyses.

RESULTS

A sample of 439 professionals participated in the survey. Only 6.4% of the physical therapists use the most recommended measures/criteria for return to sport after anterior cruciate ligament reconstruction. Professional certification in Sports Physical Therapy was the only factor associated with the use of these recommended measures/criteria (p=0.02). The measures most used for return to sport clearance were related to physical factors (65.3% to 75.1%), such as range of motion and muscle strength. A small number of professionals use questionnaires to assess functional (16.6%) and psychological (19.1%) aspects of their patients to support the decision-making process.

CONCLUSION

In their clinical practice, most Brazilian physical therapists do not use the recommended measures/criteria for return to sport after anterior cruciate ligament reconstruction.

Evaluation of Anterolateral Ligament Healing After Anatomic Anterior Cruciate Ligament Reconstruction

BACKGROUND

Few studies have reported the healing process of anterolateral ligament (ALL) injuries.

PURPOSE/HYPOTHESIS

This study investigated the healing status of ALL injuries after primary anterior cruciate ligament (ACL) reconstruction (ACLR). Additionally, we investigated the association between the healing status of ALL injuries and associated lesions such as osseous lesions and meniscal tears occurring at the time of an ACL rupture. We hypothesized that acute ALL injuries show a high rate (more than two-thirds) of healing at the 1-year follow-up after ACLR and that concomitant lesions observed at the time of an ACL rupture affect the healing status of the ALL.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

We retrospectively investigated patients with ALL injuries who underwent primary ACLR between March 2015 and February 2017. Using magnetic resonance imaging (MRI), we evaluated the features of ALL injuries and concomitant lesions, and MRI was performed at the 1-year follow-up to assess the healing status of the ALL. We investigated the association between the healing status of the ALL and concomitant lesions observed at the time of an ACL rupture. A subjective assessment was performed using the Lysholm score, International Knee Documentation Committee subjective score, and Tegner activity scale. Objective tests included an isokinetic strength assessment and functional performance testing.

RESULTS

With respect to the severity of ALL injuries, of 54 patients, a complete rupture occurred in 16 (29.6%) of the 54 patients and a partial rupture in 38 (70%). A significant association was observed between the severity of ALL injuries and bone contusions (lateral tibial plateau and medial tibial plateau [MTP]) and meniscus ramp lesions (Fisher exact test: P = .023, .012, and .023, respectively). Good and partial healing of the ALL occurred in 16 (29.6%) and 23 (42.6%) of 54 patients, respectively. Scar formation occurred in 12 (22.2%), and nonvisualization of the ALL was observed in 3 (5.6%) of 54 patients. Poor healing of the ALL was associated with preoperative MTP bone contusions and a high-grade pivot shift. Multivariate analysis showed that an MTP bone contusion was an independent risk factor associated with poor healing of the ALL. Among the functional tests performed, significant differences were observed between the good and poor healing groups with respect to the carioca test (P = .039). The good healing group (n = 16) showed a negative pivot shift at the last follow-up, whereas 5 (13.2%) of the patients from the poor healing group (n = 38) showed a positive pivot shift, including 2 (5.3%) with a high-grade pivot shift.

CONCLUSION

Approximately 70% of acute ALL injuries showed poor healing at the 1-year follow-up. Poor healing of ALL injuries was significantly associated with preoperative MTP bone contusions and a high-grade pivot shift. Therefore, a careful assessment of posteromedial bone contusions at the time of an ACL rupture is warranted, particularly in patients with a high-grade pivot shift.

Anatomic medial complex reconstruction in serious medial knee instability results in excellent mid-term outcomes

PURPOSE

To evaluate the mid-term outcomes of anatomic medial complex reconstruction in cases of serious medial knee instability.

METHODS

Between 2010 and 2013, 23 patients who underwent anatomic medial complex reconstruction with a minimum 5-year follow-up were included. The Lysholm score, International Knee Documentation Committee subjective knee form (IKDC SKF), and Tegner activity scale scores were evaluated. Clinical and functional tests included valgus and sagittal stress tests, isokinetic muscle strength test, single leg hop for distance test (SLDT), and single leg vertical jump test (SLVT).

RESULTS

The mean follow-up duration was 77.2 ± 10.8 months. At final follow-up, the Lysholm score improved from 49.7 ± 10.2 to 93.4 ± 12.4; the IKDC SKF score, from 46.2 ± 8.7 to 90.5 ± 13.9; and median Tegner activity, from 5 (4-7) to 7 (4-10) (P < 0.001). The mean side-to-side difference on valgus stress radiographs was significantly reduced to 1.2 ± 0.7 mm postoperatively compared to 8.5 ± 1.6 mm preoperatively (P < 0.001). The mean side-to-side differences on anterior and posterior stress radiographs were significantly improved in concomitant ACL and PCL reconstructions, respectively (P < 0.001). Preoperatively, 17 patients (73.9%) had anteromedial rotatory instability (AMRI), but none had AMRI at the last follow-up. The extensor peak torque and Limb Symmetry Index (LSI, %) improved from 128.2 ± 42.9 to 225 ± 39.4 N m/kg and from 61.4 ± 19.6 to 88.7 ± 21.7%, respectively (P < 0.001). The LSI (%) for SLDT and SLVT improved from 56.8 ± 19.5 to 87.3 ± 14.2% and from 68.1 ± 21.1 to 91.1 ± 12.8%, respectively (P < 0.001). No patient had a restricted range of movement.

CONCLUSION

Although posteromedial corner injuries that need medial complex reconstruction are extremely rare, proper anatomic medial complex reconstruction of the medial collateral and posterior oblique ligaments achieved satisfactory clinical and functional outcomes at mid-term follow-up in cases with chronic symptomatic valgus and rotatory laxity.

LEVEL OF EVIDENCE

Case series, level IV.