Sex-Specific Differences in Psychological Response to Injury and Return to Sport Following ACL Reconstruction

Impact of Psychological Factors on Rehabilitation After Anterior Cruciate Ligament Reconstruction: A Systematic Review

CONTEXT

Anterior cruciate ligament (ACL) tears are a common orthopaedic injury, and the incidence of ACL reconstruction (ACLR) continues to increase. Current clinical practice guidelines (CPGs) recognize the role of psychological factors in rehabilitation, but patient-reported outcome measures (PROs) and psychological readiness are rarely incorporated into rehabilitation.

OBJECTIVE

The purpose of this review was to highlight the importance of psychological health after ACL injury, understand the current metrics used to monitor psychological recovery, and outline how psychological recovery can be better incorporated in current CPGs.

DATA SOURCES

A systematic review was conducted using the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines (PRISMA); 63 studies were identified with a PubMed search using the term "ACL Injuries/psychology".

STUDY SELECTION

Exclusion criteria included lack of consideration of psychological effects or studies validating PROs after ACLR. Studies were reviewed by multiple reviewers, and a total of 38 studies were included after applying exclusion criteria.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 3b.

DATA EXTRACTION

Two independent reviewers analyzed the included articles to extract sample size, psychological readiness scale or other measures used, and key results.

RESULTS

Psychological outcomes, especially kinesiophobia and fear of reinjury, are seen commonly after ACLR. Psychological factors were shown to impede return to sport (RTS), alter measurable knee biomechanics, and potentially increase the risk for re-rupture. Targeted interventions such as kinesiotaping, knee bracing, and imagery training can help improve psychological and functional testing after ACLR.

CONCLUSION

ACLR is often complicated by psychological factors. Psychological readiness is a crucial yet often unincorporated part of rehabilitation. Patients with higher levels of kinesiophobia and lower psychological readiness to RTS specifically should be identified to allow for administration of interventions, such as imagery training, knee bracing, or kinesiotaping, that can mitigate the negative effects of psychological outcomes and improve recovery.

Sex-based differences in physical and psychological recovery, and return to sport, following anterior cruciate ligament reconstruction

BACKGROUND

A robust comparison of the recovery pathway between sexes after anterior cruciate ligament reconstruction (ACLR) is lacking. This study investigated sex-based differences in physical and psychological recovery, and return to sport (RTS), after ACLR.

METHODS

104 community-level patients underwent ACLR. Patients were evaluated at 6-, 12- and 24-months with the Anterior Cruciate Ligament Return to Sport after Injury Scale (ACL-RSI), International Knee Documentation Committee (IKDC) form and Tegner Activity Scale (TAS), a 4-hop test battery including the 6-meter timed hop (6MTH) and the single (SHD), triple (THD) and triple crossover (TCHD) hop tests for distance, and peak isokinetic knee extensor and flexor torque. Sex-based differences were assessed, while regression analysis modelled the relationship between patient characteristics and outcomes, with 24-month psychological readiness to RTS.

RESULTS

All PROMS improved (p < 0.05), with males reporting higher 24-month ACL-RSI (p = 0.002), IKDC (p = 0.007) and TAS (p = 0.005) scores. A greater percentage of males returned to pivoting sports at 24 months (p = 0.030, males 60.0%, females 40.8%). Males demonstrated higher knee extensor strength LSIs at 6 (p = 0.037) and 24 (p = 0.047) months, and higher knee flexor strength LSIs at 6 (p = 0.007) and 12 (p = 0.002) months. IKDC knee scores (β = 24.9; 95% CI, 10.8 to 35.0), male sex (β = 12.2; 95% CI, 3.9 to 20.4) and the 6MTH LSI (β = 1.31; 95% CI, 0.6 to 2.1) were associated with the ACL-RSI.

CONCLUSIONS

In community-level ACLR patients, females demonstrated lower physical performance recovery, subjective function and psychological readiness, as well as a lower rate of RTS.

Sex specific considerations in anterior cruciate ligament injuries in the female athlete: State of the art

The increased participation of females in sports has been accompanied by an increase in the rate of anterior cruciate ligament (ACL) injuries. The literature has identified risk factors for noncontact ACL injuries in female athletes, including anatomic, hormonal, biomechanical, neuromuscular, and environmental factors. This review will provide an overview of sex-specific considerations when managing female athletes with ACL injuries. A discussion of sex-specific surgical and rehabilitative treatment strategies with the goal of optimizing return to sport after ACL reconstruction will be emphasized.

In the medium term, more than half of males report kinesiophobia after anterior cruciate ligament reconstruction

OBJECTIVES

Anterior cruciate ligament rupture is a serious trauma with long-term consequences for the patient. Psychological and physiological factors may negatively affect patient recovery after anterior cruciate ligament reconstruction (ACLR), and development of kinesiophobia is possible. The aim of this study was to examine the presence of kinesiophobia and lower-leg muscle strength recovery in both sexes after ACLR.

METHODS

140 ACLR patients agreed to participate in the study. Kinesiophobia was assessed using the Tampa Scale of Kinesiophobia (TSK). The Knee injury and Osteoarthritis Outcome Score (KOOS), Oxford Knee Score (OKS) and Tegner Activity Scale (TAS) were used for patient-related outcome measurements. In both legs quadriceps and hamstring muscle strength at 60°/s and 180°/s were measured with an isokinetic dynamometer. For dynamic balance and leg function, the Y-balance test and single-leg hop test were used.

RESULTS

100 (71%) males and 40 (29%) females-mean age 32.5 (±8.3)-were examined 5.5 (±1.25) years after ACLR. 68/140 patients (48.6%) reported a TSK kinesiophobia score equal to or higher than 37 points: 54/100 (54%) males and 14/40 (35%) females (p ​= ​0.04). Patients with kinesiophobia had significantly lower KOOS values (p ​< ​0.001). In terms of the TAS no significant differences were found between those with or without kinesiophobia. Knee strength deficiency at 180°/sec and 60°/sec was significantly higher in the kinesiophobia group in knee extension in males (p ​= ​0.009) and knee flexion in females (p ​= ​0.001). Normalized body weight isokinetic average peak torque strength tests were significantly better in males compared to females in both groups (p ​< ​0.001).

CONCLUSION

Both sexes reported high rates of kinesiophobia, but males are at higher risk of developing kinesiophobia than females in the medium term after ACLR. Furthermore, patients with kinesiophobia have significantly lower total KOOS scores, and females were significantly weaker than males in knee flexion and extension according to normalized body weight muscle strength tests. Also, a longer time from injury to surgery increases the risk of kinesiophobia in females.

LEVEL OF EVIDENCE

Level IV.

TYPE OF STUDY

Retrospective case series study.

CLINICAL TRIAL REGISTRATION

Trial registration in ClinicalTrials.gov. Identifier: NCT05762809.

Females demonstrate lower levels of activity, psychological readiness and strength symmetry after anterior cruciate ligament reconstruction than males, and also recovery of quadriceps strength and hop symmetry is delayed in females undergoing reconstruction with a quadriceps tendon autograft

PURPOSE

To investigate sex-based recovery differences in patients undergoing anterior cruciate ligament reconstruction (ACLR) with a hamstring (HT) or quadriceps (QT) tendon autograft.

METHODS

This study included 97 patients, including 50 females (HT = 25, QT = 25) and 47 males (HT = 24, QT = 23), assessed presurgery and at 12- and 24-month postoperatively via surveys, laxity, isokinetic knee extensor and flexor torque and a 6-hop performance battery. Limb symmetry indices (LSIs) were calculated. Outcomes were compared between males and females, as well as within each graft type.

RESULTS

Males reported significantly higher Tegner scores at 12 (p = 0.029) and 24 (p = 0.031) months, Anterior Cruciate Ligament Return to Sport after Injury scores at 12 (p = 0.009) and 24 (p = 0.010) months, and a significantly higher lateral hop LSI at 12 (p = 0.045) months, knee extensor torque LSI at 12 (p = 0.020) months, and knee flexor torque LSI at 12 (p = 0.001) and 24 (p = 0.039) months. Females undergoing ACLR with a QT (vs. HT) graft demonstrated a lower knee extensor torque LSI at 12 (p = 0.006) months, a lower lateral hop LSI at 12 (p = 0.038) months, and a lower medial hop LSI at 12 (p = 0.042) months.

CONCLUSIONS

Females reported less activity and psychological readiness, as well as strength symmetry. Furthermore, the recovery of quadriceps strength and hop symmetry was delayed in females (vs. males) undergoing ACLR with a QT graft. A better understanding of these differences will assist in counselling on expectations, determining the most appropriate graft construct and permitting more targeted rehabilitation.

LEVEL OF EVIDENCE

Level IV.

Effect of Time and Sex on Post-Anterior Cruciate Ligament Reconstruction Psychological Patient-Reported Outcome Measure Scores

CONTEXT

Low scores on psychological patient-reported outcomes measures, including the Anterior Cruciate Ligament-Return to Sport After Injury (ACL-RSI) and Injury-Psychological Readiness to Return to Sport (I-PRRS), after anterior cruciate ligament reconstruction (ACLR) have been associated with a maladaptive psychological response to injury and poor prognosis.

OBJECTIVE

To assess the effect of time post-ACLR and sex on ACL-RSI and I-PRRS scores and generate normative reference curves.

DESIGN

Case series.

SETTING

Outpatient sports medicine and orthopaedic clinic.

PATIENTS OR OTHER PARTICIPANTS

A total of 507 patients (age at ACLR, 17.9 ± 3.0 years) who had undergone primary ACLR and completed ACL-RSI or I-PRRS assessments ≥1 times (n = 796) between 0 and 1 year post-ACLR.

MAIN OUTCOME MEASURE(S)

An honest broker provided anonymous data from our institution's knee-injury clinical database. Generalized additive models for location, scale, and shape and generalized least-squares analyses were used to assess the effect of time post-ACLR and sex on ACL-RSI and I-PRRS scores.

RESULTS

The ACL-RSI and I-PRRS scores increased over time post-ACLR. Males had higher scores than females until approximately 5 months post-ACLR, with scores converging thereafter.

CONCLUSIONS

Males reported higher ACL-RSI and I-PRRS scores than females in the initial stages of rehabilitation, but scores converged between sexes at times associated with return to play post-ACLR. Normative reference curves can be used to objectively appraise ACL-RSI and I-PRRS scores at any time post-ACLR. This may lead to timely recognition of patients with a maladaptive psychological response to injury and a higher likelihood of a poor prognosis, optimizing ACLR outcomes.

Editorial Commentary: Women Do Not Return to Sport at the Same Level After Anterior Cruciate Ligament Reconstruction as Often as Men: This May Be Associated With Lower Risk Tolerance-and Not Necessarily a Bad Thing!

It has been established that women do not return to preinjury sports (RTS) at the same level after anterior cruciate ligament reconstruction at the same rate as men. Normalization of strength parameters does influence the return to sports in men, but not women. Lower RTS rates may be associated with lower risk tolerance, and this is not necessarily a bad thing. Neither lower RTS rates nor lower risk tolerance is maladaptive or in need of correction. Awareness of the psychological diversity between the sexes does help in understanding this difference. Appreciation of this perspective will improve the relationship with the female athlete during her recovery.

Return to sports in female athletes after anterior cruciate ligament reconstruction: A systematic review and metanalysis

IMPORTANCE

Return to sport (RTS) is considered an indicator of successful recovery after anterior cruciate ligament reconstruction (ACLR). In recent years, there has been major interest in documenting RTS following anterior cruciate ligament (ACL) injury. Despite women being at increased risk for ACL injuries and a global increase in women's participation in sports, research has not adequately focused on female athletes.

OBJECTIVE

The purpose of this study is to conduct a systematic review and meta-analysis evaluating the RTS rate in female athletes after ACLR. We hypothesize that most of the female athletes can RTS.

EVIDENCE REVIEW

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Electronic databases (PubMed, Embase, and Epistemonikos) were searched for articles reporting RTS rates and contextual data in female athletes. The following search terms were used: "anterior cruciate ligament reconstruction" OR "ACL reconstruction" AND "female" OR "women" AND "return to sports" OR "return to play" to retrieve all relevant articles published between 2003 and 2023. A quality assessment of the included studies was conducted.

FINDINGS

Fifteen articles were included, reporting on 1456 female athletes participating in pivoting sports. The included studies comprised 9 cohorts, 1 case-control study, 2 case series, 2 descriptive epidemiology studies, and 1 observational study. Eight out of fifteen studies focused solely on elite-level athletes. The participants had a mean age of 23.13 years. Soccer was the most prevalent sport among the participants, accounting for 49.7% of all athletes included. All 15 studies reported an RTS rate, yielding a meta-proportion of 69% [95% CI, 58-80%] for RTS. Nine articles reported the average time to RTS, which was 10.8 months [95% CI, 8.7-12.8 months].

CONCLUSIONS

This systematic review demonstrates that a majority of female athletes (69 ​%) can RTS participation at an average of 10.8 months, however, the available information is insufficient, and quantitative data and reasons for not returning to play are lacking. Future studies should establish return-to-play criteria in this population and determine reasons for not returning to play.

LEVEL OF EVIDENCE

III.

Return to Work After Anterior Cruciate Ligament Reconstruction: A Systematic Review

Background

The timing of return to work (RTW) after anterior cruciate ligament (ACL) reconstruction (ACLR) is a less studied milestone compared with return to sports.

Purpose

To systematically review the rate and postoperative timing of RTW after ACLR.

Study Design

Systematic review; Level of evidence, 4.

Methods

This study was conducted in accordance with the 2020 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. A literature search was performed in PubMed, Embase, Cochrane, and Ovid databases for clinical studies reporting RTW after ACLR, and 806 studies were identified in August 2022. A quality assessment was performed using the Methodological Index of Nonrandomized Studies (MINORS) grading system. The following data were extracted from studies: study characteristics, cohort demographics, ACLR technique, concomitant meniscal and/or cartilage procedures, preoperative patient-reported outcomes, rates of RTW, and days required for RTW after ACLR.

Results

A total of 13 studies met inclusion criteria, totaling 1791 patients (86.4% male). Wide variability was observed in the methodological quality of the assessed studies (MINORS score range, 8-17). Hamstring tendon (HT) autograft was used in 76.8% (n = 1377; mean age, 30.5 years old), allograft in 17.1% (n = 308; mean age, 33.1 years old), the ligament advanced reinforcement system in 2.5% (n = 46; mean age, 33.2 years old), bone-patellar tendon-bone autograft in 2% (n = 36; mean age, 28.5 years old), and quadriceps tendon autograft in 1.3% (n = 24; mean age, 24.1 years old). Among the included patients, 99.1% (n = 1781) reported successful RTW after surgery. The mean time to RTW was 84.2 days (range, 31.4-107.1 days) for HT and 69.5 days (range, 49-56.6 days) for allograft.

Conclusion

While data regarding work intensity before and after ACL injury were absent, our study results suggested that patients most often RTW within 90 days of surgery. Patients with allograft ACLR may RTW earlier than patients undergoing ACLR with HT autograft.

Comparison of ACL and Anterolateral Ligament Reconstruction With Isolated ACL Reconstruction Using Hamstring Autograft: Outcomes in Young Female Patients With High-Grade Pivot Shift

Background

Inferior return to sports (RTS) and functional outcomes have been reported in women after anterior cruciate ligament reconstruction (ACLR).

Purpose/Hypothesis

The purpose was to evaluate the results of combined ACLR and anterolateral ligament reconstruction (ALLR) in young women with a high-grade pivot shift (grade ≥2). It was hypothesized that combined ACLR and ALLR would result in better RTS and rotational stability than isolated ACLR.

Study Design

Cohort study; Level of evidence, 3.

Methods

Two groups were retrospectively evaluated and compared. Group I (n = 39; mean age, 31.1 ± 5.7 years) underwent isolated ACLR using hamstring autografts; group C (n = 39; mean age, 30.4 ± 6.1 years) underwent combined ACLR and ALLR. Subjective outcome measures included the International Knee Documentation Committee subjective form, Lysholm, Tegner, and ACL-Return to Sport after Injury (ACL-RSI). Objective tests included a KT-2000 arthrometer stress test, a pivot-shift test, an isokinetic strength test, a Y-balance test, and a single-leg hop test. A postoperative questionnaire was administered to determine the rates and types of RTS, quality of sports performance, and reinjury and satisfaction rates. Subjective scores and clinical tests were performed at 2 years. Magnetic resonance imaging and second-look arthroscopy were conducted during the 1- and 2-year follow-ups, respectively.

Results

The mean follow-up for groups I and C were 30.4 ± 3.9 and 29.3 ± 3.5 months, respectively (P = .194). Patients in group C had better anteroposterior (P = .001) and rotational (P = .005) stability and higher ACL-RSI scores (P = .025) than those in group I. Group C had higher composite and posteromedial reach scores on the Y-balance test than group I (P = .014 and P = .010, respectively). A total of 26 (66.7%) patients in group C and 17 (43.6%) in group I returned to their prior level of sports (P = .040). Rerupture of the ACL graft and contralateral ACL rupture occurred in 2 (5.1%) and 2 (5.1%) patients in group I, respectively, compared with no rerupture or contralateral ACL rupture in group C.

Conclusion

Combined ACLR and ALLR in young women with a high-grade pivot shift was associated with better knee stability parameters, dynamic postural stability, and psychological readiness to RTS than isolated ACLR.

Psychological Aspects of Return to Sport for the Female Athlete

Female athletes represent a unique population of competitors who face distinct stressors when compared with male athletes. These include sport inequities, violence, abuse, body image concerns, disordered eating, relative energy deficiency, family planning challenges, hormonal challenges, and mental distress. When combined with sports injuries, these stressors can negatively impact the mental health of female athletes as well as their injury recovery and return to sports. It is essential for orthopaedic surgeons to be familiar with the unique aspects inherent to being a female athlete, along with the psychological aspects of sports injuries. By integrating questions about female athletes' psychological well-being into their routine practice and collaborating with a multidisciplinary team, orthopaedic surgeons can better address these unique stressors, support female athletes in achieving optimal outcomes, and enhance return to sport rates.

Level of Evidence

V, expert opinion.

Effect of Age and Sex on Psychological Readiness and Patient-Reported Outcomes 6 Months After Primary ACL Reconstruction

Background

Successful return to sport after anterior cruciate ligament (ACL) reconstruction (ACLR) can be affected by a patient's physical and psychological state throughout the rehabilitation process.

Purpose

To prospectively compare differences in patients at 6 months after primary ACLR with the ACL-Return to Sport after Injury (ACL-RSI), International Knee Documentation Committee (IKDC) or pediatric (Pedi)-IKDC, Hospital for Special Surgery Pediatric Functional Activity Brief Scale (Pedi-FABS), and Patient-Reported Outcomes Measurement Information System-Psychological Stress Experiences (PROMIS-PSE) scores.

Study Design

Prospective cohort study; Level of evidence, 2.

Methods

Patients enrolled were 8 to 35 years old who underwent primary ACLR and had their 6-month follow-up appointments between December 2018 and March 2020. Patients were divided into 3 age groups as follows: (1) preadolescents (10-14 years); (2) adolescents (15-18 years); and (3) adults (>18 years). Outcomes on the ACL-RSI, IKDC/Pedi-IKDC, Pedi-FABS, and PROMIS-PSE were compared according to age group, graft type (hamstring, patellar tendon, quadriceps, or iliotibial band autograft), and sex.

Results

A total of 176 patients (69 male, 107 female), with a mean age of 17.1 ± 3.1 years were included in the study. The mean ACL-RSI scores were significantly different among age groups (preadolescents, 75 ± 18.9; adolescents, 61.5 ± 20.4; and adults, 52.5 ± 19.8 [P < .001]) and graft types (P = .024). The IKDC and PROMIS-PSE scores were also significantly different among age groups (P < .001 and P = .044, respectively) and graft types (P = .034 and P < .001, respectively), with the iliotibial graft and the younger age group performing the best. There was no significant difference in the Pedi-FABS either by age group (P = .127) or graft type (P = .198). Female patients had lower ACL-RSI scores and higher (worse) scores on PROMIS-PSE than their male counterparts (P = .019 and P < .001, respectively), with no sex-based differences on IKDC or Pedi-FABS scores. The ACL-RSI and IKDC were positively correlated (Spearman r = 0.57; P < .001), while the ACL-RSI and PROMIS-PSE were negatively correlated (Pearson r = -0.34; P < .001).

Conclusion

This study suggests that psychological profiles and subjective perceptions of knee function 6 months after ACLR may vary in patients of different ages and between the sexes. Preadolescent patients had better scores on a majority of patient-reported outcomes compared with adolescent and adult patients.

Improvement Trajectories in Patient-Reported Outcomes Between Males and Females After Anterior Cruciate Ligament Reconstruction

CONTEXT

Patient-reported outcomes (PROs) are used to track recovery and inform clinical decision-making after anterior cruciate ligament reconstruction (ACLR). Whether sex influences the trajectory of improvements in PROs over time post-ACLR remains unclear.

OBJECTIVES

To (1) examine the effect of sex on the association between months post-ACLR and Knee injury and Osteoarthritis Outcome Score (KOOS) Quality of Life (QOL) scores in individuals with ACLR and (2) assess sex differences in the KOOS QOL score at selected timepoints post-ACLR.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 133 females (20± 3 years) and 85 males (22 ± 4 years) within 6 to 60 months of primary, unilateral ACLR.

MAIN OUTCOME MEASURE(S)

The KOOS QOL was completed at a single follow-up timepoint post-ACLR. A multivariate linear regression model was calculated to assess the interaction of sex on the association between months post-ACLR and KOOS QOL score. Sex-specific linear regression models were then used to predict KOOS QOL estimated marginal means at each clinical timepoint (6, 12, 24, 36, 48, and 60 months post-ACLR) and compare the sexes.

RESULTS

In the primary model (R2 = 0.16, P < .0001), a significant interaction existed between sex and time post-ACLR (β = -0.46, P < .01). Greater months post-ACLR were associated with better KOOS QOL scores for males (R2 = 0.29, β = 0.69, P < .001); months post-ACLR was a weaker predictor of KOOS QOL scores for females (R2 = 0.04, β = 0.23, P < .02). Estimated marginal means for KOOS QOL scores were greater for males than females at 36 months (t210 = 2.76, P < .01), 48 months (t210 = 3.02, P < .01), and 60 months (t210 = 3.09, P = .02) post-ACLR.

CONCLUSIONS

Males exhibited PRO improvement post-ACLR as the months post-ACLR increased, whereas females did not demonstrate the same magnitude of linear increase in KOOS QOL score. Females may require extended intervention to improve clinical outcomes post-ACLR and address a plateau in QOL score.

Let's talk about sex (and gender) after ACL injury: a systematic review and meta-analysis of self-reported activity and knee-related outcomes

OBJECTIVE

Investigate sex/gender differences in self-reported activity and knee-related outcomes after anterior cruciate ligament (ACL) injury.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

Seven databases were searched in December 2021.

ELIGIBILITY CRITERIA

Observational or interventional studies with self-reported activity (including return to sport) or knee-related outcomes after ACL injury.

RESULTS

We included 242 studies (n=123 687, 43% females/women/girls, mean age 26 years at surgery). One hundred and six studies contributed to 1 of 35 meta-analyses (n=59 552). After ACL injury/reconstruction, very low-certainty evidence suggests females/women/girls had inferior self-reported activity (ie, return to sport, Tegner Activity Score, Marx Activity Scale) compared with males/men/boys on most (88%, 7/8) meta-analyses. Females/women/girls had 23%-25% reduced odds of returning to sport within 1-year post-ACL injury/reconstruction (12 studies, OR 0.76 95% CI 0.63 to 0.92), 1-5 years (45 studies, OR 0.75 95% CI 0.69 to 0.82) and 5-10 years (9 studies, OR 0.77 95% CI 0.57 to 1.04). Age-stratified analysis (<19 years) suggests female athletes/girls had 32% reduced odds of returning to sport compared with male athletes/boys (OR 0.68, 95% CI 0.41 to 1.13, I² 0.0%). Very low-certainty evidence suggests females/women/girls experienced inferior knee-related outcomes (eg, function, quality of life) on many (70%, 19/27) meta-analyses: standardised mean difference ranging from -0.02 (Knee injury and Osteoarthritis Outcome Score, KOOS-activities of daily living, 9 studies, 95% CI -0.05 to 0.02) to -0.31 (KOOS-sport and recreation, 7 studies, 95% CI -0.36 to -0.26).

CONCLUSIONS

Very low-certainty evidence suggests inferior self-reported activity and knee-related outcomes for females/women/girls compared with males/men/boys after an ACL injury. Future studies should explore factors and design targeted interventions to improve outcomes for females/women/girls.

PROSPERO REGISTRATION NUMBER

CRD42021205998.

Fear of reinjury following primary anterior cruciate ligament reconstruction: a systematic review

PURPOSE

This review aims to elucidate the most commonly reported method to quantify fear of reinjury or kinesiophobia and to identify key variables that influence the degree of kinesiophobia following primary anterior cruciate ligament reconstruction (ACLR).

METHODS

A systematic search across three databases (Pubmed, Ovid (MEDLINE), and EMBASE) was conducted from database inception to August 7th, 2022. The authors adhered to the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. Quality assessment of the included studies was conducted according to the Methodological Index for Non-Randomized Studies (MINORS) criteria.

RESULTS

Twenty-six studies satisfied the inclusion criteria and resulted in 2,213 total patients with a mean age of 27.6 years and a mean follow-up time of 36.7 months post-surgery. The mean MINORS score of the included studies was 11 out of 16 for non-comparative studies and 18 out of 24 for comparative studies. Eighty-eight percent of included studies used variations of the Tampa Scale of Kinesiophobia (TSK) to quantify kinesiophobia and 27.0% used Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI). The results of this study shows a common association between higher kinesiophobia and poor patient-reported functional status measured using International Knee Documentation Committee (IKDC) Scores, Activity of Daily Living (ADL), Quality of Life (QOL), and Sports/Recreation (S/R) subscales of Knee Osteoarthritis and Outcome Score (KOOS) and Lysholm scores. Postoperative symptoms and pain catastrophizing measured using the KOOS pain and symptom subscales and Pain Catastrophizing Score (PCS) also influenced the degree of kinesiophobia following ACLR. Patients with an increased injury to surgery time and being closer to the date of surgery postoperatively demonstrated higher levels of kinesiophobia. Less common variables included being a female patient, low preoperative and postoperative activity status and low self-efficacy.

CONCLUSION

The most common methods used to report kinesiophobia following primary ACLR were variations of the TSK scale followed by ACL-RSI. The most commonly reported factors influencing higher kinesiophobia in this patient population include lower patient-reported functional status, more severe postoperative symptoms such as pain, increased injury to surgery time, and being closer to the date of surgery postoperatively. Kinesiophobia following primary ACLR is a critical element affecting post-surgical outcomes, and screening should be implemented postoperatively to potentially treat in rehabilitation and recovery.

LEVEL OF EVIDENCE

IV.

Changes in subjective knee function and psychological status from preoperation to 6 months post anterior cruciate ligament reconstruction

Purpose

To determine characteristic changes in subjective knee function, kinesiophobia, and psychological readiness to return to sports between scores taken before anterior cruciate ligament reconstruction (ACLR) and those taken 6 months post-ACLR.

Methods

Thirty-two participants (median age, 20.0 years) were included. Subjective knee function was assessed using the International Knee Documentation Committee Subjective Knee Form (IKDC-SKF). The Tampa Scale for Kinesiophobia (TSK-11) and Anterior Cruciate Ligament Return to Sport after Injury (ACL-RSI) scale were used to evaluate kinesiophobia and psychological readiness to return to sport, respectively. Questionnaires were administered 1 day before surgery and at 6 months post-ACLR. A positive change was defined as an increase in IKDC-SKF and ACL-RSI scores and a decrease in TSK-11 score. The change in each score from pre-ACLR to 6 months post-ACLR was analyzed using a paired t-test. The percentage change in scores was calculated, and the correlations of the percentage change in the TSK-11 and ACL-RSI scores and that in the IKDC-SKF score were analyzed.

Results

All scores differed significantly positively from pre-ACLR to 6 months post-ACLR. The proportion of participants whose scores did not change positively from pre-ACLR to 6 months post-ACLR was higher for the TSK-11 (38.0%) and ACL-RSI (38.0%) than for the IKDC-SKF (6.3%). No correlation was observed between the percentage change in the IKDC-SKF score and that in the TSK-11 or ACL-RSI scores from pre-ACLR to 6 months post-ACLR.

Conclusions

Changes in subjective knee function and psychological status from pre-ACLR and 6 months post-ACLR may not be interdependent.

Sex-Specific Outcomes After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

Background:

Despite the significant difference between men and women in incidence of anterior cruciate ligament (ACL) injuries, there is a paucity of consistent information on the influence of patient sex on outcomes after ACL reconstruction. A previous meta-analysis has demonstrated that female patients have worse outcomes with regard to laxity, revision rate, Lysholm score, and Tegner activity score and are less likely to return to sports (RTS).

Purpose:

To conduct a systematic review and meta-analysis to evaluate and compare sex-specific outcomes after ACL reconstruction.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review was performed using PubMed, PubMed Central, Embase, OVID, and Cochrane databases per PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The following search terms were used: “anterior cruciate ligament reconstruction” OR “ACL reconstruction” OR “anterior cruciate ligament” OR “ACL” AND “gender” OR “sex” OR “male” OR “female” AND “outcome” AND “2015-Present” to gather all relevant articles between 2015 and 2020. A risk-of-bias assessment and quality assessment was conducted on included studies.

Results:

Of 9594 studies initially identified, 20 studies with 35,935 male and 21,455 female patients were included for analysis. The 7 studies reporting International Knee Documentation Committee (IKDC) scores showed that male patients had statistically significantly higher postoperative scores (mean difference, 3.02 [95% CI, 1.19-4.84]; P< .01; I² = 66%), and 7 studies that reported the rate of ACL revision showed there was no significant difference between male and female patients (odds ratio, 0.85 [95% CI, 0.45-1.60]; P = .61; I² = 94%). The 7 studies that reported rates of rerupture showed that males were significantly more likely than females to have a graft rerupture (odds ratio, 1.35 [95% CI, 1.22-1.50]; P < .01; I² = 0%). Male patients reported a higher RTS rate than did their female counterparts (59.82% compared with 42.89%); however, no formal statistical analysis could be done because of the variability in reporting techniques.

Conclusion:

Male and female patients with ACL injuries demonstrated similar outcomes regarding their rates of revision; however, male patients were found to have statistically significantly higher postoperative IKDC scores but at the same time higher rerupture rates. Our findings suggest that sex-based differences in outcomes after ACL reconstruction vary based on which metric is used. These results must be considered when counseling patients with ACL injuries.

Disparities in ACL Reconstruction: the Influence of Gender and Race on Incidence, Treatment, and Outcomes

PURPOSE OF REVIEW

Anterior cruciate ligament (ACL) rupture is a common injury that has important clinical and economic implications. We aimed to review the literature to identify gender, racial and ethnic disparities in incidence, treatment, and outcomes of ACL injury.

RECENT FINDINGS

Females are at increased risk for ACL injury compared to males. Intrinsic differences such as increased quadriceps angle and increased posterior tibial slope may be contributing factors. Despite lower rates of injury, males undergo ACL reconstruction (ACLR) more frequently. There is conflicting evidence regarding gender differences in graft failure and ACL revision rates, but males demonstrate higher return to sport (RTS) rates. Females report worse functional outcome scores and have worse biomechanical metrics following ACLR. Direct evidence of racial and ethnic disparities is limited, but present. White athletes have greater risk of ACL injury compared to Black athletes. Non-White and Spanish-speaking patients are less likely to undergo ACLR after ACL tear. Black and Hispanic youth have greater surgical delay to ACLR, increased risk for loss to clinical follow-up, and less physical therapy sessions, thereby leading to greater deficits in knee extensor strength during rehabilitation. Hispanic and Black patients also have greater risk for hospital admission after ACLR, though this disparity is improving. Females have higher rates of ACL injury with inconclusive evidence on anatomic predisposition and ACL failure rate differences between genders. Recent literature has suggested inferior RTS and functional outcomes following ACLR in females. Though there is limited and mixed data on incidence and outcome differences between races and ethnic groups, recent studies suggest there may be disparities in those who undergo ACLR and time to treatment.

The psychological readiness to return to sports of patients with anterior cruciate ligament reconstruction preoperatively and 6 months postoperatively

OBJECTIVE

To determine the association of psychological readiness to return to sports preoperative and 6 months post-reconstruction in athletes with anterior cruciate ligament (ACL) injury.

DESIGN

Retrospective cohort study.

SETTING

Clinical center of sports medicine.

PARTICIPANTS

Fifty athletes, aged 16-45 years, were included in this study. Participants had a modified Tegner activity scale score ≥5 before ACL injury.

MAIN OUTCOME MEASURES

Participants were divided into High and Low groups based on ACL-return to sport after injury scale (ACL-RSI) scores 6 months post-ACL reconstruction (ACLR) (cutoff: 56 points).

RESULTS

The Low group had lower ACL-RSI scores than the High group preoperatively (P < 0.001) and 6 months post-ACLR (P < 0.001). The High group had a significantly greater amount of change in ACL-RSI scores preoperatively to 6 months post-ACLR than the Low group (P = 0.003). Preoperative ACL-RSI scores increased significantly to 6 months post-ACLR in the entire group of participants (P < 0.001) and in the High group (P < 0.001). However, in the Low group, ACL-RSI scores did not increase significantly (P = 0.714).

CONCLUSIONS

Participants with low ACL-RSI scores 6 months post-ACLR had low preoperative ACL-RSI scores that did not improve preoperatively to 6 months post-ACLR.

Knee performance and self-efficacy trajectory curves after ACL reconstruction: A longitudinal study

OBJECTIVES

To examine knee flexion range-of-motion, quadriceps strength, and knee self-efficacy trajectory curves over 6 months after anterior cruciate ligament reconstruction (ACLR), stratified by patients' Month-6 sports activity level.

DESIGN

Prospective longitudinal study.

SETTING

Hospital outpatient physiotherapy department.

PARTICIPANTS

595 individuals after unilateral ACLR (mean age, 27 years).

MAIN OUTCOME MEASURES

At 2-, 3-, and 6-months post-surgery, knee flexion range-of-motion, quadriceps strength, and self-efficacy were quantified. Flexion range-of-motion was additionally measured at 2- and 4-weeks post-surgery. Sports activity levels were assessed using the Tegner Activity Score at 6-months post ACLR.

RESULTS

The various measures improved nonlinearly over time, with substantial improvements observed in the first 2-4 months post-surgery. In multivariable generalized least squares models, greater knee flexion range-of-motion, quadriceps strength, and self-efficacy over time were significantly associated with higher Month-6 Tegner levels (all P values < 0.01). Additionally, receiving a bone-patellar-tendon-bone graft or meniscal repair was associated with lower quadriceps strength trajectories (P-values<0.001) while female sex was associated with lower knee self-efficacy trajectories (P = 0.02).

CONCLUSIONS

Greater knee flexion range-of-motion, quadriceps strength, and self-efficacy were associated with higher Month-6 Tegner levels. The derived trajectory curves may be useful for effective management decision making and adequate results interpretation during the rehabilitation process.

A Comparison of Psychological Readiness and Patient-Reported Function Between Sexes After Anterior Cruciate Ligament Reconstruction

CONTEXT

Postoperative functional and return-to-sport outcomes after anterior cruciate ligament reconstruction (ACLR) differ by sex. However, whether sex disparities are observed in patient-reported outcome measures (PROMS) before return to sport after ACLR is unclear.

OBJECTIVES

To compare common PROMS between young men and women who had not yet returned to sport after ACLR.

DESIGN

Cross-sectional study.

SETTING

University laboratory.

MAIN OUTCOME MEASURE(S)

Forty-five young men (age = 18.7 ± 2.7 years, time since surgery = 6.8 ± 1.4 months) and 45 matched for age (±1 year) and time since surgery (±1 month; age = 18.8 ± 2.8 years, time since surgery = 6.9 ± 1.4 months) with ACLR participated. Participants completed the Tegner Activity Scale, ACL Return to Sport After Injury scale, Tampa Scale of Kinesiophobia, International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Score, and Knee Injury and Osteoarthritis Outcome Score (KOOS). The PROMS were compared between men and women using Mann-Whitney U tests. Odds ratios were calculated to evaluate the odds of a male reporting a PROM value above the previously established normative value as compared with a female.

RESULTS

Sex differences were present for the IKDC score (P = .01) and KOOS Pain score (P = .04) but not for the Tegner activity level (P = .22), ACL Return to Sport after Injury scale score (P = .78), Tampa Scale of Kinesiophobia score (P = .64), or other KOOS subscales (P values = .40 to .52). The odds of reporting values above normative levels differed only for the IKDC score (odds ratio = 2.72, 95% confidence level = 1.16, 6.38).

CONCLUSIONS

After ACLR, young men and women reported similar levels of knee-related function, fear of movement, and readiness for return to sport and were equally likely to meet clinically meaningful normative values before return to sport. Overreliance on patient reports or objective functional outcomes in evaluating patient progress and readiness for return to sport after ACLR may limit clinicians in their ability to comprehensively evaluate and develop individualized interventional approaches that optimize patient outcomes.

Gender Differences in Psychological Responses to Recovery After Anterior Cruciate Ligament Reconstruction Before Return to Sport

CONTEXT

Female patients with anterior cruciate ligament reconstruction (ACLR) are less likely to return to sport than males. Psychological readiness predicts successful return to sport, but it is unclear if psychological experiences differ between males and females during recovery.

OBJECTIVE

To explore gender differences in psychological readiness factors of return to sport after ACLR.

DESIGN

Qualitative study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 12 male (months since surgery = 6.2 ± 1.2) and 13 female (months since surgery = 6.4 ± 1.3) high school athletes with a history of ACLR.

DATA COLLECTION AND ANALYSIS

Participants were interviewed before physician clearance to return to activity. Transcribed interviews were analyzed using deductive thematic coding of 5 themes identified from previous research (psychological distress, self-efficacy, locus of control, athletic identity, and fear of reinjury) and inductive secondary subthematic coding. Gender comparisons were generated within primary themes and secondary subthemes.

RESULTS

All deductive themes were consistently reinforced. Male and female participants reported fear of movement, loss of athletic identity, and motivational mindsets for return to sport and self-improvement. Males reported a stronger sense of internal locus of control using positive internal reinforcement, whereas females described balancing internal and external control and valuing external support systems. Male participants described mood changes influenced by physical and social limitations. Female participants closely monitored their emotions throughout recovery and were influenced by rehabilitation fluctuations.

CONCLUSIONS

Male and female high school athletes described different psychological factors related to return to sport and locus of control as well as psychological distress. Gender-specific psychological interventions may be warranted to overcome psychological barriers after ACLR.

The Influence, Barriers to and Facilitators of Anterior Cruciate Ligament Rehabilitation Adherence and Participation: a Scoping Review

BACKGROUND

Outcomes following anterior cruciate ligament (ACL) reconstruction are considered poor. There are many factors which may influence patient outcomes. As such, the purpose of this review was to report on the influence, barriers to and facilitators of rehabilitation adherence and participation after ACL reconstruction, providing information to help clinicians and patients make quality decisions to facilitate successful rehabilitation.

METHODS

A systematic search of five electronic databases was undertaken in identifying studies from inception to 18 July 2019. The search included English language articles reporting on the influence, barriers to and facilitators of adherence and participation in rehabilitation of patients who have undergone ACL reconstruction. Data extraction and synthesis of included studies were undertaken.

RESULTS

Full text articles (n = 180) were assessed for eligibility following screening of titles and abstracts (n = 1967), yielding 71 studies for inclusion. Forty-four articles investigated 'rehabilitation prescription and participation' and 36 articles investigated 'rehabilitation barriers and facilitators'. The results indicate that a moderately or minimally supervised rehabilitation program is at least as effective as a fully supervised high-frequency rehabilitation program, although a longer duration of supervised rehabilitation is associated with improvement in a multitude of functional outcomes. A number of psychological factors associated with rehabilitation adherence were also identified. The most commonly investigated concepts were self-motivation, athletic identity and social support. Patients perceived the therapeutic relationship, interaction with family and friends, self-motivation, fear of reinjury, organisation/lack of time and interpersonal comparison as the most common barriers to and facilitators of rehabilitation.

CONCLUSIONS

A longer duration of supervised rehabilitation is associated with an increased chance of meeting functional and return to sport criteria; however, the optimal supervised rehabilitation frequency is yet to be determined. Identification of the barriers to and facilitators of adherence and participation in ACL rehabilitation provides an opportunity for further research to be conducted to address personal, environmental and treatment-related factors, with the aim to improve rehabilitation outcomes.

Smaller Change in Psychological Readiness to Return to Sport Is Associated With Second Anterior Cruciate Ligament Injury Among Younger Patients

BACKGROUND

Lower psychological readiness to return to sport has been reported for younger patients (≤20 years) who go on to a second anterior cruciate ligament (ACL) injury. However, changes in psychological readiness and specific psychological responses associated with second injury have not been identified.

PURPOSE/HYPOTHESIS

To identify changes in psychological readiness over time associated with a second ACL injury. It was hypothesized that younger patients who suffered a second injury would have smaller changes in psychological readiness to return to sport when compared with those who did not have a second injury.

STUDY DESIGN

Case-control study; Level of evidence, 2.

METHODS

Patients ≤20 years old at the time of surgery who had a primary ACL reconstruction procedure between June 2014 and June 2016 were recruited for this study. The short version of the Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) scale was completed by patients before their ACL reconstruction and repeated at 12 months after surgery to assess psychological readiness to return to sport. The primary outcome of interest was the relationship between the change in psychological readiness and second ACL injuries.

RESULTS

Among 115 young patients who returned to sport after ACL reconstruction, 21 (18%) experienced a second ACL injury. Injured patients did not show improvement in their ACL-RSI score between the preoperative assessment and 12-month time point (58.5 vs 60.8 points, P = .60) and had a significantly smaller change when compared with noninjured patients (9.2 vs 24.9 points, P = .01). When compared with the noninjured group, the injured group reported they were more nervous about playing sport, less confident in playing sport without concern for the knee, more frustrated with having to consider the knee with respect to sport, and more fearful of reinjuring the knee by playing sport ( P≤ .05).

CONCLUSION

Injured patients exhibited less improvement in psychological readiness at a group level and reported different psychological characteristics with regard to return to sport at 12 months after ACL reconstruction as monitored by the ACL-RSI scale.