An Ecological Study of Anterior Cruciate Ligament Reconstruction, Part 1: Clinical Tests Do Not Correlate With Return-to-Sport Outcomes

Return to sport after anterior cruciate ligament reconstruction - prognostic factors and prognostic models: A systematic review

BACKGROUND

A variety of criteria are used to make return to sport decisions after anterior cruciate ligament (ACL) reconstruction.

OBJECTIVES

This systematic review summarized and evaluated prognostic factors and clinical prognostic models for returning to sports after ACL reconstruction.

METHODS

Independent pairs of reviewers assessed eligibility, extracted data, and evaluated risk of bias and certainty of evidence. A systematic literature search was conducted in key electronic databases.

INCLUSION CRITERIA

studies published in English, longitudinal cohort or case-control design, reporting outcomes on return to sport or Tegner Activity Score (TAS), participants aged ≥16 years undergoing primary ACL reconstruction, and defined as athletes/sport players or having a pre-injury TAS ≥5. Only associations between predictors and outcomes that were analyzed in ≥3 studies and had consistent results in the same direction in ≥75 % of the studies were considered and reported. Risk of bias was evaluated using the QUIPS or PROBAST tools, and certainty of evidence was evaluated using the GRADE framework.

RESULTS

37 studies (5 low, 6 moderate, and 26 high risk of bias) on prognostic factors and 1 study on prognostic models (low risk of bias), representing 6278 participants, were included. Six prognostic factors were identified and rated as very low certainty evidence: fewer concomitant meniscal injuries, shorter time between injury and surgery, higher jump test scores, better physical functioning, higher muscle strength, and greater psychological readiness to return to sport. Two prognostic models with AUC 0.77-0.78 and 70 % accuracy for predicting return to sport were identified.

CONCLUSION

There is a very low certainty of evidence that returning to sport is associated with both physical, psychological and demographic prognostic factors. More methodologically sound research on prognostic factors and prognostic models for return to sport in athletes after ACL reconstruction is needed.

A Preliminary Study of Post-Market Bridge-Enhanced ACL Restoration (BEAR) Suggests Non-Inferior Short-Term Outcomes and Low Complications

Background

To improve outcomes following anterior cruciate ligament (ACL) reconstruction, bridge-enhanced ACL restoration (BEAR) was introduced. Bridge-enhanced ACL restoration uses a collagen-based implant saturated with infused autologous blood to bridge the torn proximal and distal ACL fibers.

Purpose

We sought to analyze the short-term complications, clinical outcomes, and patient-reported outcome measures (PROMs) in patients undergoing BEAR outside of the initial clinical trials.

Methods

We conducted a retrospective cohort study of all skeletally mature patients who had a midsubstance or proximal ACL tear treated with BEAR by 2 surgeons at a single institution and had a minimum follow-up of 6 weeks. A total of 58 patients were included (average age was 38 years, average time from injury to surgery was 45 days). Data on demographic factors, functional outcomes, and complications were collected from electronic medical records. Patient-reported outcome measures and a descriptive return-to-activity survey were analyzed utilizing paired t-tests and Wilcoxon signed-rank tests.

Results

All 58 patients demonstrated a grade of 1A on the Lachman test at 6 weeks postoperatively. At 6 months postoperatively, the mean active flexion was 135° ± 5°, and all patients achieved 0° extension. Although not all patients completed PROM questionnaires, among those who did we observed a significant increase in PROMs between preoperative and postoperative measurements; more than half achieved the minimal clinically important difference in all PROMs, and 26 patients (87%) had a 1-level decrease in function. There were no cases of retear or instability. Three patients (5%) had postoperative arthrofibrosis.

Conclusion

Early results of this preliminary post-market approval study suggest that BEAR may provide a safe and non-inferior approach to ACL reconstruction in selected patients. Studies are needed to investigate the long-term outcomes of this novel technique.

A new method of anterior talofibular ligament reconstruction: Arthroscopically artificial ligament reconstruction with tensional remnant-repair

PURPOSE

To investigate the clinical effects of arthroscopically artificial ligament reconstruction with tensional remnant-repair in patients who are obese, and/or with demand for highly intensive sports, and/or with poor-quality ligament remnants.

METHODS

A retrospective case series study was performed on patients treated by arthroscopically anterior talofibular ligament (ATFL) reconstruction with tensional remnant repair technique from January 2019 to August 2021. General data, including demographics, surgical time, and postoperative adverse events, were recorded. The American Orthopaedic Foot and Ankle Society score (AOFAS), foot and ankle ability measure (FAAM), visual analog scale (VAS), and anterior talar translation were measured preoperatively and at 6 weeks, 3 months, and 2 years postoperatively. Ultrasonography examination was performed preoperatively and 2 years postoperatively to evaluate the ATFL. Data were analyzed using SPSS 19.0. F test was used to analyze the pre- and postoperative VAS, FAAM, and AOFAS scores. The significance was set at p < 0.05.

RESULTS

There were 20 males and 10 females among the patients with a mean age of (30.71 ± 5.81) years. The average surgical time was (40.21 ± 8.59) min. No adverse events were observed after surgery. At 2 years postoperatively, the anterior talar translation test showed grade 0 laxity in all patients. VAS score significantly decreased from preoperatively to 6 weeks, 3 months, and 2 years postoperatively (p < 0.001). Improvement of FAAM score and the AOFAS score from preoperatively to 6 weeks, 3 months, and 2 years postoperatively was statistically significant (p < 0.001). At 3 months postoperatively, most patients (23/30) could return to their pre-injured activities of daily living status. At 2 years postoperatively, all patients were able to return to their pre-injured activities of daily living status, and almost every patient (18/19) who expected highly intensive sports returned to sports with only 1 obese patient failing to achieve the goal. The ultrasonography examination at 2 years postoperatively showed that there was a linear band structure of soft tissue on the tension-rich fiber tape image from the fibular to the talar attachment sits of ATFL.

CONCLUSION

The novel arthroscopically artificial ligament reconstruction with tensional remnant-repair technique for ATFL achieved satisfactory clinical outcomes in the short and medium term after operation, and allowed early return to pre-injured activities, which could be a reliable option for patients with chronic lateral ankle instability.

Preoperative predictors for return to physical activity following anterior cruciate ligament reconstruction (ACLR): a systematic review

BACKGROUND

Rates of return to physical activity after anterior cruciate ligament reconstruction surgery are sub-optimal. Optimising presurgical treatment may improve return rates. The purpose of this systematic review was to identify modifiable preoperative predictors for return to physical activity after anterior cruciate ligament reconstruction.

METHODS

Seven electronic databases (CINAHL, MEDLINE and SPORTDiscus via EBSCOhost, AMED, PsycINFO and EMBASE via OVID and Web of Science) were searched from inception to 31 March 2023. The population of focus was adults aged 18-65 who had undergone primary anterior cruciate ligament reconstruction. Studies needed to identify at least one potential modifiable preoperative predictor variable and the relationship between the predictor(s) and return to physical activity. All time-points of assessment and study designs were included. Data extraction was completed by one reviewer and verified by a second reviewer. Two reviewers completed the risk of bias assessment using the Quality in Prognostic Studies tool and Grading of Recommendations Assessment, Development and Evaluation system.

RESULTS

The search identified 2281 studies, eight met the inclusion criteria. Five studies scored 'high', and three studies scored 'moderate' risk-of-bias. All preoperative predictors were of very low-quality evidence. Five different outcome measures were used to assess return to physical activity including Tegner, Marx, Physical Activity Scale, return to play at the elite level and return to preinjury level (undefined). This was measured between 1- and 10-years post-surgery. Nine preoperative physical, six psychosocial and five demographic/clinical factors were assessed and four were found to be predictive. These included quadriceps strength, psychological profile, patient estimated ability to return and graft type (patella tendon, BPTB).

CONCLUSION

Very-low level evidence suggests that increasing quadriceps strength, managing patient expectations of their treatment outcomes, improving motivation to resume preinjury activity levels and considering the use of a BPTB graft will support return to physical activity after ACLR.

TRIAL REGISTRATION

This study was prospectively registered in PROSPERO: CRD 42020222567.

Earlier Resolution of Symptoms and Return of Function After Bridge-Enhanced Anterior Cruciate Ligament Repair As Compared With Anterior Cruciate Ligament Reconstruction

Background:

Bridge-enhanced anterior cruciate ligament repair (BEAR) has noninferior patient-reported outcomes when compared with autograft anterior cruciate ligament reconstruction (ACLR) at 2 years. However, the comparison of BEAR and autograft ACLR at earlier time points—including important outcomes such as resolution of knee pain and symptoms, recovery of strength, and return to sport—has not yet been reported.

Hypothesis:

It was hypothesized that the BEAR group would have higher outcomes on the International Knee Documentation Committee and Knee injury and Osteoarthritis Outcome Score, as well as improved muscle strength, in the early postoperative period.

Study Design:

Randomized controlled trial; Level of evidence, 1.

Methods:

A total of 100 patients aged 13 to 35 years with complete midsubstance anterior cruciate ligament injuries were randomized to receive a suture repair augmented with an extracellular matrix implant (n = 65) or an autograft ACLR (n = 35). Outcomes were assessed at time points up to 2 years postoperatively. Mixed-model repeated-measures analyses were used to compare BEAR and ACLR outcomes. Patients were unblinded after their 2-year visit.

Results:

Repeated-measures testing revealed a significant effect of group on the International Knee Documentation Committee Subjective Score (P = .015), most pronounced at 6 months after surgery (BEAR = 86 points vs ACLR = 78 points; P = .001). There was a significant effect of group on the Knee injury and Osteoarthritis Outcome Score-Symptoms subscale scores (P = .010), largely attributed to the higher BEAR scores at the 1-year postoperative time point (88 vs 82; P = .009). The effect of group on hamstring strength was significant in the repeated-measures analysis (P < .001), as well as at all postoperative time points (P < .001 for all comparisons). At 1 year after surgery, approximately 88% of the patients in the BEAR group and 76% of the ACLR group had been cleared for return to sport (P = .261).

Conclusion:

Patients undergoing the BEAR procedure had earlier resolution of symptoms and increased satisfaction about their knee function, as well as improved resolution of hamstring muscle strength throughout the 2-year follow-up period.

Registration:

NCT02664545 (ClinicalTrials.gov identifier)

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.

Monitoring changes in knee surface morphology after anterior cruciate ligament reconstruction surgery using 3Dsurface scanning

STUDY DESIGN

Prospective case series.

BACKGROUND

After surgical reconstruction of the anterior cruciate ligament, recovery to pre-injury levels of knee function is challenging. Postoperative edema and muscle atrophy are common roadblocks to full function and are evident in changes to the surface morphology of the knee. There are currently few accessible objective tools to accurately track these morphological changes.

OBJECTIVES

We aimed to determine if 3D surface scanning can be used to monitor changes in the external shape of the knee after surgery and throughout the rehabilitation process.

METHODS

Thirty participants had 3D surface scans taken of their knee, along with questionnaire-based functional outcomes prior to surgery (baseline), and at two-week, six-week, 12-week, and 26-week timepoints post-surgery. Volumetric changes relative to pre-op were assessed using generalized linear growth models for key anatomical regions and correlated with functional outcomes.

RESULTS

Significant swelling of the patella region compared to baseline was evident immediately after surgery (14%, p < 0.001), before returning to pre-operative levels. Changes in volume at this region were significantly associated with patient-reported functional outcomes. Reductions in volume of the regions corresponding to the vastus medialis and lateralis muscles were significant at 12 weeks post-surgery (p = 0.018 and 0.01 respectively) but returned to baseline levels at six months.

CONCLUSION

We demonstrate the use of 3D surface scanning as a method for capturing detailed measurements of knee surface morphology after surgery. Significant changes in external morphology are evident during the rehabilitation process.

Nearly 90% participation in sports activity 12 years after non-surgical management for anterior cruciate ligament injury relates to physical outcome measures

PURPOSE

Traditionally reconstructive surgery is recommended for patients planning to return to sport (RTS), especially to pivoting sports after anterior cruciate (ACL) rupture. Recent trends focus on delaying or avoiding surgery as some studies have found similar rates of RTS following both surgical and conservative management. This study aimed to establish long-term RTS levels in ACL-ruptured individuals treated conservatively, and to investigate the relationship between outcome measures and RTS, in particular, pivoting sports.

METHOD

Fifty-five patients from a cohort of 132 ACL-deficient patients were followed-up for  12 (IQR 8,19) years post injury. Mean-aged 42 years, 22 patients were females and 33 males, 35 had meniscal injuries. Patients were treated with physiotherapy focussing on strength and dynamic stability training and not reconstructive surgery. Return to sport was measured on a 6-point scale. Outcome measures included: objective stability, subjective stability, quadriceps and hamstring strength. Spearman's rho and Chi-square tests were used to assess the relationship between RTS and outcome measures.

RESULTS

Eighty-nine percent of ACL-deficient patients were currently participating in sport despite a 38% increase in anterior translation (p < 0.001) and a 7.5% loss of quadriceps strength (p = 0.004) compared to the contralateral side. Six patients (11%) did not RTS, ten (18%) returned to safe sports, five (9%) returned to running and 16 (29%) to non-strenuous sports involving limited twisting. Eighteen patients (33%) returned to pivoting sports, 12(22%) at recreational level and six (11%) at competitive level. The level of RTS was related to subjective stability (p = 0.002), and to quadriceps and hamstring strength of the injured leg (p < 0.001). Patients able to return to pivoting sports differed significantly from those not doing so in outcome measures including objective (p = 0.022) and subjective stability (p = 0.035), and quadriceps strength (p = 0.044).

CONCLUSIONS

Eighty-nine percent of ACL-ruptured individuals treated conservatively lead an active sporting life. One-third returned to pivoting sports.  Overall RTS was related to subjective and objective stability and quadriceps and to a lesser extent hamstring strength. This finding reinforced the importance of dynamic stability training as an initial treatment option in most cases.

LEVEL OF EVIDENCE

III.

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

BACKGROUND

The aim of this study was to identify the correlations between the single-leg vertical jump (SLVJ) test and subjective and objective tests which were used widely for determining return-to-sports (RTS) after anterior cruciate ligament reconstruction (ACLR).

METHODS

Seventy-five patients (29.5 ± 9.2 years) who underwent ACLR between May 2012 and Jan 2014 were included. Subjective knee scoring systems including subjective International Knee Documentation Committee (IKDC) score, Lysholm score, Tegner activity scale, and ACL-Return to Sports after Injury (ACL-RSI) scale were assessed. Objective tests were also performed.

RESULTS

The limb symmetry index (LSI) for SLVJ test and single-leg hop for distance (SLHD) test was 89.4 ± 14.9% and 90.7 ± 11.7%. LSI for SLVJ test was correlated to subjective IKDC scores (r = 0.26, P = 0.024), Tegner activity scale (r = 0.64, P < 0.001), ACL-RSI scale (r = 0.61, P < 0.001), LSI for SLHD (r = 0.45, P < 0.001), Co-contraction (r = -0.57, P < 0.001), Shuttle run (r = -0.52, P < 0.001), and Carioca (r = -0.54, P < 0.001) tests. In isokinetic strength tests, extensor peak torque (r = 0.30, P = 0.009) and extensor strength deficit (r = -0.41, P < 0.001) were correlated with LSI for SLVJ test.

CONCLUSION

There were considerable correlations between SLVJ test and subjective IKDC scores, Tegner activity scale, ACL-RSI scale, isokinetic extensor muscle strength, and all other functional tests. SLVJ test could be used conveniently to determine RTS after ACLR in outpatient clinics.

LEVEL OF EVIDENCE

Level IV, case series.

ACL Return to Sport Guidelines and Criteria

PURPOSE OF REVIEW

Because of the epidemiological incidence of anterior cruciate ligament (ACL) injuries, the high reinjury rates that occur when returning back to sports, the actual number of patients that return to the same premorbid level of competition, the high incidence of osteoarthritis at 5-10-year follow-ups, and the effects on the long-term health of the knee and the quality of life for the patient, individualizing the return to sports after ACL reconstruction (ACL-R) is critical. However, one of the challenging but unsolved dilemmas is what criteria and clinical decision making should be used to return an athlete back to sports following an ACL-R. This article describes an example of a functional testing algorithm (FTA) as one method for clinical decision making based on quantitative and qualitative testing and assessment utilized to make informed decisions to return an athlete to their sports safely and without compromised performance. The methods were a review of the best current evidence to support a FTA.

RECENT FINDINGS

In order to evaluate all the complicated domains of the clinical decision making for individualizing the return to sports after ACL-R, numerous assessments need to be performed including the biopsychosocial concepts, impairment testing, strength and power testing, functional testing, and patient-reported outcomes (PROs). The optimum criteria to use for individualizing the return to sports after ACL-R remain elusive. However, since this decision needs to be made on a regular basis with the safety and performance factors of the patient involved, this FTA provides one method of quantitatively and qualitatively making the decisions. Admittedly, there is no predictive validity of this system, but it does provide practical guidelines to facilitate the clinical decision making process for return to sports. The clinical decision to return an athlete back into competition has significant implications ranging from the safety of the athlete, to performance factors and actual litigation issues. By using a multifactorial FTA, such as the one described, provides quantitative and qualitatively criteria to make an informed decision in the best interests of the athlete.

An Ecological Study of Anterior Cruciate Ligament Reconstruction, Part 2: Functional Performance Tests Correlate With Return-to-Sport Outcomes

Background:

Additional high-quality prospective studies are needed to better define the objective criteria used in relation to return-to-sport decisions after anterior cruciate ligament (ACL) reconstruction in active populations.

Purpose:

To investigate prospectively the relationship between functional performance test results at 24 weeks postoperative and return-to-sport activity (Tegner activity score) at 12 and 24 months, respectively, after synthetic (ligament advanced reinforcement system [LARS]) and autograft (doubled semitendinosus/gracilis [2ST/2GR]) ACL reconstructions.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 64 patients who underwent ACL reconstruction (32 LARS, 32 2ST/2GR autograft; mean age, 27.9 years; body mass index [BMI], 24.9 kg/m²) were assessed preoperatively and at staged intervals postoperatively up to 24 weeks for isokinetic testing of quadriceps and hamstring average power per repetition at 60 deg/s and 180 deg/s, a battery of hop tests, peak vertical ground-reaction force (vGRF), and time to peak vGRF (in seconds) during a step- and jump-down task onto a force platform and peak speed (m/s) using a global positioning system (GPS unit) during a running task. A cohort of 32 healthy matched participants (mean age, 26.31 years; BMI, 25.7 kg/m²) were also tested to act as reference. Pearson correlation was calculated to assess correlation of each performance measure at 24 weeks postoperative with activity outcomes (Tegner score) at 12 and 24 months.

Results:

The strongest correlation between physical performance tests and return-to-sport outcomes was observed with peak speed during running. Large correlations were also observed for hamstring isokinetic power and hop test for distance. Moderate correlations were observed for timed hop, peak vGRF during a jump-down task, and quadriceps isokinetic power. No statistical correlations were observed for time to peak vGRF during a step-down and jump-down task as well as peak vGRF during a step-down task. When the performance tests were pooled together, mean postoperative improvements of 24% were observed from preoperative to 24 weeks within the surgical cohort. For each performance test, preoperative level of function strongly correlated with performance levels on the same test at 24 weeks.

Discussion:

The results of this study indicate that clinicians might seek to prioritize these tests and the rehabilitation themes they imply when seeking to maximize postoperative ACL activity outcomes. The observed strength between pre- and postoperative performance tests and return-to-sport outcomes within this study highlights the potential value of preoperative conditioning before undergoing ACL reconstruction. Future research should examine absolute predictive criterion thresholds for functional performance-based tests and reinjury risk reduction after ACL reconstruction.