High Risk of New Knee Injuries in Female Soccer Players After Primary Anterior Cruciate Ligament Reconstruction at 5- to 10-Year Follow-up

Return to the Pre-Injury Level of Sport after Anterior Cruciate Ligament Reconstruction: A Practical Review with Medical Recommendations

Returning to sport after anterior cruciate ligament reconstruction (ACLR) can be a challenging and complex process for the athlete, with the rate of return to the pre-injury level of sport observed to be less than athlete expectations. Of the athletes that do return to sport (RTS), knee re-injury rates remain high, and multiple studies have observed impaired athletic performance upon RTS after ACLR as well as reduced playing time, productivity, and career lengths. To mitigate re-injury and improve RTS outcomes, multiple RTS after ACLR consensus statements/clinical practice guidelines have recommended objective RTS testing criteria to be met prior to medical clearance for unrestricted sports participation. While the achievement of RTS testing criteria can improve RTS rates after ACLR, current criteria do not appear valid for predicting safe RTS. Therefore, there is a need to review the various factors related to the successful return to the pre-injury level of sport after ACLR, clarify the utility of objective performance testing and RTS criteria, further discuss safe RTS decision-making as well as present strategies to reduce the risk of ACL injury/re-injury upon RTS. This article provides a practical review of the current RTS after ACLR literature, as well as makes medical recommendations for rehabilitation and RTS decision-making after ACLR.

Rehabilitation and Return to Sport After Anterior Cruciate Ligament Reconstruction

Rehabilitation after an anterior cruciate ligament (ACL) reconstruction requires patience, devotion, and discipline. Rehabilitation should be individualized to each patient's specific need and sport. Return to sport is a continuum throughout the rehabilitation, and patients should not return to performance before passing a battery of muscle function tests and patient-reported outcomes, as well as change of direction-specific tests. Return to full participation should be an agreement between the patient, physical therapist, surgeon, and coach. For minimal risk for second ACL injury, patients should continue with maintenance and prevention training even after returning to sport.

Athletes' perspectives on return to sport after anterior cruciate ligament reconstruction and their strategies to reduce reinjury risk: a qualitative interview study

BACKGROUND

Insights derived from athletes who have completed the final phase of rehabilitation and successfully returned to their respective sports after anterior cruciate ligament (ACL) reconstruction could potentially contribute to the enhancement of therapeutic strategies. Therefore, the aim of this study was to explore athletes' experiences, thoughts, and behaviours of final phase rehabilitation and return to sport after ACL reconstruction and to describe their thoughts about the risk of reinjury.

METHODS

This qualitative interview study included individual semi-structured interviews with 15 athletes after ACL reconstruction. All athletes were aged between 15 and 35 years (median, 23 years), had returned to their preinjury contact sport at elite or recreational competitive level, rehabilitated with different physioterapists (working in hospital, primary care or sport clinics), and had undergone primary ACL reconstruction between 14 and 59 months (median, 23 months) before the interviews. Data were analysed using qualitative content analysis.

RESULTS

Analysis of the data resulted in the following 4 main categories related to athletes' experiences of the return to sport process and their thoughts about the risk of reinjury: Athletes' strategies for safe return to sport; Support during rehabilitation and return to sport; The rehabilitation journey was worthwhile to be able to play again; and Reinjury is beyond one's control.

CONCLUSIONS

Athletes described strategies for a safe return to sport after ACL reconstruction, emphasizing continuous increased load, not forcing return to sport, injury prevention exercises, and seeking support from professionals and coaches. Despite loving their sport, the athletes had mixed feelings about undergoing additional rehabilitation if reinjured. The athletes recognized the high reinjury risk, attributing it to fate. These findings enhance understanding of athletes' return to sport experiences after ACL reconstruction, their strategies to minimize reinjury risk, which might help optimizing care for this patient group.

Return to Play and Performance After Anterior Cruciate Ligament Reconstruction in Soccer Players: A Systematic Review of Recent Evidence

BACKGROUND

The available literature referring to the return to play (RTP) and performance after anterior cruciate ligament reconstruction (ACLR) has already been comprehensively summarized in team sports such as basketball or American Football. Therefore, in this sense, it is necessary to synthesize evidence relating to the mentioned parameters in soccer players who underwent ACLR.

OBJECTIVE

The aim of this systematic review was to examine RTP and the performance of soccer players after ACLR.

METHODS

Three electronic databases, Web of Science, Scopus, and PubMed, have been comprehensively searched to identify relevant articles. The following inclusion criteria were applied: (1) the sample of respondents consisted of soccer players irrespective of their age, sex, or level of competition; (2) athletes experienced anterior cruciate ligament injury and underwent ACLR; (3) outcomes estimated referred to the RTP, RTP at the preinjury level of competition, RTP time, performance, and career duration of soccer players; (4) studies were written in the English language. The methodological quality of the research was evaluated using the Methodological Index for Non-Randomized Studies (MINORS).

RESULTS

Databases searched yielded a total of 694 studies, of which 17 fulfilled the eligibility criteria and were included in the final analysis. These included 3657 soccer players, 2845 males and 812 females, who underwent ACLR and most commonly competed at the elite, national, amateur, and recreational levels. The results obtained indicated that 72% of soccer players successfully RTP and 53% RTP at the preinjury level of participation after ACLR. In addition, recent evidence provided in this literature review demonstrated that mean RTP time was 264 days or 8.7 months. Moreover, the majority of the studies unambiguously suggested that performance related to statistical aspects noticeably deteriorated compared with both the preinjury period and noninjured athletes. The mean career length of soccer players following ACL surgery was approximately between 4 and 5 years.

CONCLUSION

Although a high percentage of athletes RTP after a relatively short period of absence from the sports field compared with other sports closely related to soccer, ACLR negatively impacts soccer players' performance and career duration.

Injury prevention in Brazilian women's football: Perceptions of physiotherapists and practices within elite clubs

OBJECTIVES

To describe the perceptions of physiotherapists and the injury prevention practices implemented within elite women's football clubs in Brazil.

DESIGN

Cross-sectional study.

SETTING

Online survey.

PARTICIPANTS

Head physiotherapists from 32 Brazilian elite clubs.

MAIN OUTCOME MEASURES

Structured questionnaire.

RESULTS

Physiotherapists identified ACL rupture as the primary target for prevention. The top-five perceived injury risk factors included 'early return to sport after injury', 'workload too high', 'previous injury', 'poor sleep/rest', and 'muscle strength/power deficit'. 'Adoption of return to sport criteria' was almost unanimously recognized as a very important preventive strategy. 'Poor infrastructure' was elected as the main barrier to implementing prevention programs. From a practical standpoint, at least two-third of clubs implemented multi-component exercise interventions for injury prevention. These interventions typically encompassed flexibility/mobility, balance/proprioception, lumbo-pelvic stability, and agility exercises, alongside exposure to sprinting. Strength training routines typically included traditional, functional, and eccentric exercises. Most teams also employed other prevention strategies, including adoption of return to sport criteria, internal workload monitoring, post-exercise recovery modalities, preseason risk factor screening, and application of rigid strapping tapes.

CONCLUSIONS

This study provided unprecedented insights into the physiotherapists' perceptions and injury prevention practices implemented within elite women's football clubs.

UEFA Women's Elite Club Injury Study: a prospective study on 1527 injuries over four consecutive seasons 2018/2019 to 2021/2022 reveals thigh muscle injuries to be most common and ACL injuries most burdensome

OBJECTIVE

Injuries in women's football (soccer) have scarcely been investigated, and no study has been conducted in the highest competitive level involving club teams from different countries. Our aim was to investigate the time-loss injury epidemiology and characteristics among women's elite football players over four seasons.

METHODS

596 players from 15 elite women's teams in Europe were studied prospectively during the 2018/2019 to 2021/2022 seasons (44 team seasons). Medical staff recorded individual player exposure and time-loss injuries. Injury incidence was calculated as the number of injuries per 1000 playing hours and injury burden as the number of days lost per 1000 hours.

RESULTS

1527 injuries were recorded in 463 players with an injury incidence of 6.7 (95% CI 6.4 to 7.0) injuries per 1000 hours and a nearly fourfold higher incidence during match play compared with training (18.4, 95% CI 16.9 to 19.9 vs 4.8, 95% CI 4.5 to 5.1; rate ratio 3.8, 95% CI 3.5 to 4.2). Thigh muscle injuries (hamstrings 12%, 188/1527, and quadriceps 11%, 171/1527) were the most frequent injury, while anterior cruciate ligament (ACL) injury had the highest burden (38.0 days lost per 1000 hours, IQR 29.2-52.1) with median days lost of 292 (IQR 246-334) days. Concussions constituted 3% (47/1527) of all injuries, with more than half of them (55%, 26/47) due to ball-related impact.

CONCLUSION

An elite women's football team can expect approximately 35 time-loss injuries per season. Thigh muscle injury was the most common injury and ACL injury had the highest injury burden.

Outcomes of bone-patellar tendon-bone autograft and quadriceps tendon autograft for ACL reconstruction in an all-female soccer player cohort with mean 4.8-year follow up

OBJECTIVE

The purpose is to compare functional outcomes, return to soccer rates, and revision rates in an all-female soccer player cohort undergoing quadriceps tendon (QT) autograft ACLR versus bone-patellar tendon-bone (BPTB) autograft ACLR.

METHODS

Female soccer players who sustained an ACL rupture and underwent primary anatomic, single-bundle ACLR with BPTB autograft or QT autograft were included. Demographic and surgical characteristics were collected. Outcomes of interest included Tegner score, International Knee Documentation Committee (IKDC) score, Marx score, return to soccer rates, and failure rates.

RESULTS

Data on 23 patients undergoing BPTB autograft ACLR and 14 undergoing QT autograft ACLR was available. Average age was 18.7 years, and average follow up was 4.8 years. Overall, 76 ​% (28/37) returned to soccer and 5.4 ​% (2/37) underwent revision ACLR. No major significant differences were found in demographic or surgical characteristics. No differences were found in postoperative IKDC scores, preoperative, postoperative, or change from pre-to postoperative Marx activity scores, or pre-and postoperative Tegner scores between the groups. QT autograft ACLR patients had significantly less change in Tegner scores pre-to postoperatively compared to the BTPB autograft ACLR group (0.6 ​± ​1.2 versus 2.1 ​± ​1.8; p ​= ​0.02). Both groups had similar rates of return to soccer [78 ​% (18/23) BPTB autograft ACLR versus 71 ​% (10/14) QT autograft ACLR; p ​= ​0.64] and rates of revision (8.7 % (2/23) BPTB autograft ACLR; 0 % (0/14) QT autograft ACLR.

CONCLUSION

Results of this study suggest that BPTB autograft ACLR and QT autograft ACLR produce comparable, successful functional and return to soccer outcomes in this all-female soccer player cohort study. Larger, prospective studies are needed to improve the strength of conclusions and provide more information on the optimal graft choice for female soccer players. Surgeons can use the results of this study to counsel female soccer players on expected outcomes after ACLR.

LEVEL OF EVIDENCE

III.

Knee-Related Quality of Life Compared Between 20 and 35 Years After an Anterior Cruciate Ligament Injury Treated Surgically With Primary Repair or Reconstruction, or Nonsurgically

BACKGROUND

Quality of life (QoL) is affected up to 5 years after an anterior cruciate ligament (ACL) injury. Knee impairment and osteoarthritis (OA) development increase over time, and this may affect QoL at a long-term follow-up.

PURPOSE

To investigate changes in health- and knee-related QoL between 20 and 35 years after ACL injury and compare it between patients treated with or without ACL surgery, as well as to study how symptomatic OA (SOA) is associated with change in QoL.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Between 1980 and 1983, 139 patients with acute ACL rupture were allocated to surgical or nonsurgical treatment of the ACL. Both groups completed a structured rehabilitation program. Of those patients, 59 were followed for 20 and 35 years after ACL rupture. After 10 crossovers, 33 patients were treated with primary repair or ACL reconstruction, and 26 were treated without ACL surgery. Combined radiographic OA and knee symptoms at 35 years was defined as SOA. QoL was assessed at 20 and 35 years after injury with the Knee injury and Osteoarthritis Outcome Score QoL (KOOS-QoL) subscale (range, 1-100), ACL-QoL questionnaire (total score and 5 subscales; range, 1-100), European QoL-5 Dimensions Questionnaire, and visual analog scale. Results were analyzed with paired and independent-sample t tests and chi-square tests.

RESULTS

Knee-related QoL was impaired at both 20 and 35 years after ACL injury, and differences were dependent on the measurement outcome. In the total cohort, KOOS-QoL did not change but both total ACL-QoL score (7.1 points; 95% CI, 2.2-11.9) and 4 of 5 subscales (5-10 points) decreased (P < .05). No differences were found between treatment groups. QoL decreased overall in patients with SOA, with a 21-point difference within-group change in KOOS-QoL (SOA or non-SOA) between 20 and 35 years of follow-up (P = .001; Cohen d = 1.0).

CONCLUSION

An ACL injury impairs knee-related QoL for up to 35 years, with no difference between treatment approaches (initial repair or later reconstruction compared with nonsurgical treatment). The deterioration decreases with longer follow-up. Clinicians should be aware of differences in QoL depending on the measurement outcome.

No Association Between Hamstrings-to-Quadriceps Strength Ratio and Second ACL Injuries After Accounting for Prognostic Factors: A Cohort Study of 574 Patients After ACL-Reconstruction

BACKGROUND

The stress on the anterior cruciate ligament (ACL) induced by the quadriceps can be attenuated by activation of the hamstrings by exerting an opposing torque to the anterior translation of tibia. Consequently, considering the ratio between strength of the hamstrings-to-quadriceps (HQ-ratio) may be of value to reduce the odds of second ACL injuries. The objective was therefore to evaluate (1) the association between HQ-ratio and the occurrence of a second ACL injury in patients after ACL-reconstruction within 2 years of return to preinjury sport level and (2) to compare the HQ-ratio between males and females after ACL reconstruction.

METHODS

Patients who had undergone primary ACL reconstruction and participated in knee-strenuous activity preinjury were included. Demographics, the occurrence of a second ACL injury, and muscle strength test results before returning to preinjury sport level were extracted from a rehabilitation registry. The endpoint was set at a second ACL injury or 2 years after return to preinjury sport level. A multivariable logistic regression was used to analyze the association between the HQ-ratio and a second ACL injury.

RESULTS

A total of 574 patients (50.0% female) with a mean age of 24.0 ± 9.4 years at primary ACL reconstruction were included. In the univariable logistic regression analysis, the odds of sustaining a second ACL injury decreased by 3% for every 1% increase in the HQ-ratio (OR 0.97 [95% CI 0.95-1.00], p = 0.025). After adjusting for the time from reconstruction to return to preinjury sport level, sex, preinjury sport level, graft choice, age, and body mass index, the results were no longer significant (OR 0.98 [95% CI 0.95-1.01], p = 0.16). Females had a higher HQ-ratio compared with males for both the ACL-reconstructed and uninjured side (3.7% [95% CI 5.7; 1.8%], p = 0.0002 and 3.3% [95% CI 4.6; 2.1], p < 0.001, respectively).

CONCLUSION

The HQ-ratio did not significantly affect the odds for sustaining a second ACL injury upon return to preinjury sports level after primary ACL reconstruction. Females had a significant higher HQ-ratio than males for both the ACL reconstructed and uninjured side.

Optimising the Early-Stage Rehabilitation Process Post-ACL Reconstruction

Outcomes following anterior cruciate ligament reconstruction (ACLR) need improving, with poor return-to-sport rates and a high risk of secondary re-injury. There is a need to improve rehabilitation strategies post-ACLR, if we can support enhanced patient outcomes. This paper discusses how to optimise the early-stage rehabilitation process post-ACLR. Early-stage rehabilitation is the vital foundation on which successful rehabilitation post-ACLR can occur. Without high-quality early-stage (and pre-operative) rehabilitation, patients often do not overcome major aspects of dysfunction, which limits knee function and the ability to transition through subsequent stages of rehabilitation optimally. We highlight six main dimensions during the early stage: (1) pain and swelling; (2) knee joint range of motion; (3) arthrogenic muscle inhibition and muscle strength; (4) movement quality/neuromuscular control during activities of daily living (5) psycho-social-cultural and environmental factors and (6) physical fitness preservation. The six do not share equal importance and the extent of time commitment devoted to each will depend on the individual patient. The paper provides recommendations on how to implement these into practice, discussing training planning and programming, and suggests specific screening to monitor work and when the athlete can progress to the next stage (e.g. mid-stage rehabilitation entry criteria).

Outcomes of Anterior Cruciate Ligament Reconstruction With Independently Tensioned Suture Tape Augmentation at 5-Year Follow-up

BACKGROUND

Reconstruction using autograft remains the gold standard surgical treatment for anterior cruciate ligament (ACL) injuries. However, up to 10% to 15% of patients will suffer a graft failure in the future. Cadaveric studies have demonstrated that the addition of suture tape augmentation to ACL autograft constructs can increase graft strength and reduce elongation under cyclical loading.

PURPOSE/HYPOTHESIS

This study aimed to investigate the clinical outcomes and rerupture rates after ACL reconstruction (ACLR) with suture tape augmentation. We hypothesized that augmentation with suture tape would lead to lower rerupture rates.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients undergoing primary ACLR using hamstring or patellar tendon autografts augmented with suture tape between 2015 and 2019 were recruited prospectively. Patients with multiligament injuries or a concomitant lateral extra-articular procedure were excluded. Patients were observed in person for 6 months, and patient-reported outcome measures (PROMs) were collected at 2 and 5 years postoperatively. All patients were contacted, and records were reviewed to determine the incidence of graft failure. PROMs collected were as follows: Knee injury and Osteoarthritis Outcome Score (KOOS), Veterans RAND 12-Item Health Survey (VR-12), Tegner and Marx activity scores, and visual analog scale for pain (VAS).

RESULTS

A total of 97 patients, with a mean age of 34.7 (±13.4) years, were included (76% men; 52 hamstring and 45 patellar tendon grafts). The mean graft diameter was 8 (±1) mm. There was 1 rerupture (1.1%) out of the 90 patients who were contactable at a mean of 5 years postoperatively. Median KOOS scores at 2 years were as follows: Pain, 94; Symptoms, 86; Activities of Daily Living, 99; Sport and Recreation, 82; and Quality of Life, 81. The postoperative scores were significantly higher than the preoperative scores (P < .001). The VR-12 Physical score improved from 43 preoperatively to 55 at 2 years and remained at 56 at 5 years. The VAS pain, Tegner, and Marx scores were 0, 6, and 9, respectively, at 2 years postoperatively. There was no difference in PROMs between graft types.

CONCLUSION

This study demonstrates encouraging results of suture tape augmentation of autograft ACLR for both hamstring and patellar tendon grafts. The failure rate of 1.1% at a mean follow-up of 5 years is lower than published rates for reconstruction, and PROMs results are satisfactory. The technique is safe to use and may permit a return to the preinjury sporting level with a lower chance of reinjury.

Risk Factors for Ipsilateral Versus Contralateral Reinjury After ACL Reconstruction in Athletes: A Systematic Review and Meta-analysis

Background

Anterior cruciate ligament (ACL) reinjury after ACL reconstruction (ACLR) can occur on the ipsilateral or contralateral side. Limited evidence exists regarding the difference between the incidence of reinjury to either knee, which is important in developing interventions to prevent ACL reinjury.

Purpose

To compare the reinjury rate of the ACL on the ipsilateral side versus the contralateral side in athletes after ACLR and investigate the risk factors that may cause different reinjury rates between the sides.

Study Design

Systematic review; Level of evidence, 4.

Methods

A systematic review was performed based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies that involved ACL reinjury in athletes after ACLR were reviewed. Considering several risk factors, including age and sex, a comparison of ACL reinjury incidence on the ipsilateral and contralateral sides was performed using a meta-analysis.

Results

Of the 17 selected studies, 3 were found to be at high risk of bias, and thus, 14 (n = 3424 participants) studies were included in the meta-analysis. In this athletic population, the contralateral ACL had a significantly higher rupture rate than the ipsilateral graft (risk ratio [RR], 1.41; P < .0001). Female athletes were found to have a greater risk of ACL reinjury on the contralateral versus the ipsilateral side (RR, 1.65; P = .0005), but different results were found in male athletes. (RR, 0.81; P = .21). There was no statistical difference in the incidence rate of ACL reinjury to either side in adolescent athletes (RR, 1.15; P = .28).

Conclusion

The contralateral ACL was more vulnerable to reinjury than the ipsilateral side in athletes after ACLR. Female athletes were more likely to reinjure their contralateral native ACL, while the same trend was not found in their male counterparts. The reinjury rate was comparable in both knees in adolescent athletes.

Are We Jumping to the Wrong Conclusions? Longer Jumps and More Hops in Female Football Players Who Went on to Sustain a Primary or Secondary ACL Injury Compared to Those Who Did Not

BACKGROUND

Different functional performance tests are used to assess patients in the clinic and before return to sport (RTS), where the rehabilitation goal is to reach good strength and jumping ability. A limb symmetry index of ≥ 90% is a common target in rehabilitation before RTS. The aim of this short communication is to use data from our 2-year prospective cohort study on female football players, either with or without an anterior cruciate ligament (ACL) reconstruction, to discuss whether hop performance in 3 commonly used hop tests can inform safe football participation, that is, with a low risk for ACL injury or reinjury.

METHOD

At baseline, 117 active female football players (mean age ± standard deviation, 20 ± 2 years) were included 19 ± 9 months after ACL reconstruction as well as 119 matched female knee-healthy players (age 19 ± 3 years). All players performed a single hop for distance test, 5-jump test and side hop test at baseline and were then prospectively followed for 2 years. Twenty-eight (24%) players sustained a second ACL injury and 8 (7%) sustained a primary ACL injury.

RESULTS

Longer jumps in the 5-jump test (922 cm vs. 865 cm, Cohen's d =  - 0.60) and more hops in the side hop test for both limbs (41-42 hops vs. 33-36 hops, d =  - 0.43 to - 0.60) were seen in players who sustained a second ACL injury compared with those who did not. Longer jumps in the single hop for distance test (both limbs) (139-140 cm vs. 124-125 cm, d =  - 0.38 to - 0.44), in the 5-jump test (975 cm vs. 903 cm, d = -0.42) and more hops in the side hop test (both limbs) (48-49 hops vs. 37-38 hops, d =  - 0.38 to - 0.47) were seen in players who sustained a primary ACL injury compared with those who did not.

CONCLUSIONS

The average hop performance, i.e. longer jumps or more hops, was greater in players who went on to sustain a primary or secondary ACL injury compared to those who did not over a two-year follow-up period. Even though hop tests are not used in isolation to evaluate readiness to RTS, their interpretation needs consideration in the decision-making process of returning to pivoting sports.

Self-reported knee function and activity level are reduced after primary or additional anterior cruciate ligament injury in female football players: a five-year follow-up study

BACKGROUND

Playing football involves a high risk of anterior cruciate ligament (ACL) injuries and these may affect knee function and activity level.

OBJECTIVES

To measure changes in self-reported knee function, activity level, and satisfaction with knee function and activity level in female football players with or without an ACL-reconstructed knee.

METHODS

Female football players, age 19.9 (SD 2.6) years, with either a primary ACL-reconstruction 1.6 (SD 0.7) years after ACL-reconstruction (n = 186) or no ACL injury (n = 113) were followed prospectively for five years. Self-reported data collected at baseline and follow-up included knee function (International Knee Documentation Committee Subjective Knee Form [IKDC-SKF]), activity level (Tegner Activity Scale), and satisfaction with knee function (Likert scale 1=happy; 7=unhappy) and activity level (1-10 scale). Information on any new ACL injury during the follow-up period was collected.

RESULTS

Players with ACL-reconstruction at baseline who either did (n = 56) or did not (n = 130) sustain an additional ACL injury, and players with no injury at baseline who remained injury free (n = 101) had a lower Tegner score at follow-up. Players with additional ACL injury had lower IKDC-SKF score (mean difference: -11.4, 95% CI: -16.0, -6.7), and satisfaction with activity level (mean difference: -1.5, 95% CI: -2.3, -0.7) at follow-up. Players with no additional ACL injury had higher satisfaction with knee function (mean difference: 0.6, 95% CI: 0.3, 0.9) at follow-up. Players with no ACL injury had lower satisfaction with activity level (mean difference: -0.7, 95% CI: -1.1, -0.3) at follow-up. Players with additional ACL injury had larger decreases in all variables measured compared to the two other groups.

CONCLUSION

Primary, and even more so additional, ACL injuries decreased self-reported knee function, activity level, and satisfaction with knee function and activity level in female football players.

Poorer patient-reported knee function and quality of life, but not activity level, after revision ACL reconstruction compared with primary ACL reconstruction: a matched-pair analysis with a minimum 5-year follow-up

BACKGROUND

An appropriate method for comparing knee function and activity level between patients with primary and revision anterior cruciate ligament reconstruction (ACLR) is to perform a matched-group analysis. The aim was to assess and compare knee function, knee-related quality of life and activity level between patients with revision ACLR and primary ACLR at a minimum of 5 years of follow-up.

METHODS

Patients aged ≤ 40 years old who underwent revision ACLR between 2010 and 2015 and a matched control group (primary ACLR) (1:1) with age ± 2 years, year of ACLR, sex, and pre-injury sport and Tegner Activity Scale (TAS) were retrospectively identified in our clinic database. The preoperative Knee injury and Osteoarthritis Outcome Score (KOOS) and surgical data were extracted and analyzed. Patients were mailed KOOS and EQ-5D questionnaires at a minimum of 5-years after revision ACLR. Study-specific questions about knee function, limitation in sport, satisfaction, and activity level according to the TAS (all scales of 1-10, 10 best) were also asked by telephone.

RESULTS

Seventy-eight patients with a revision ACLR (mean age ± SD, 29.9 ± 6.0 years) matched with seventy-eight patients with a primary ACLR (30.2 ± 5.8 years) were included. The follow-up for the revision ACLR group was 7.0 ± 1.5 years and for the primary ACLR group 7.7 ± 1.6 years. The revision ACLR group reported poorer KOOS scores in all subscales (p < 0.05) except the Symptoms subscale, poorer EQ-5D VAS (mean 79.2 ± 20.1 vs 86.0 ± 20.1, p = 0.012), and less satisfaction with current knee function (median 7 (6-8) vs 8 (7-9), p < 0.001). Patients with revision ACLR also experienced greater limitation in sports (median 7 (4-8) vs 8 (6-9), p < 0.001). There were no significant differences in the EQ-5D (mean 0.86 ± 0.17 vs 0.89 ± 0.11, p = 0.427), activity level (median 2 (2-5) vs 4 (2-7), p = 0.229), or satisfaction with activity level (median 8 (5-9) vs 8 (6-10), p = 0.281) between the groups.

CONCLUSIONS

At a minimum 5-year follow-up, the revision ACLR group reported poorer knee function and quality of life, less satisfaction with knee function and a greater limitation in sports but no differences in activity level and satisfaction with activity level compared with the primary ACLR group.

Higher age and present injury at the start of the season are risk factors for in-season injury in amateur male and female football players-a prospective cohort study

PURPOSE

To describe the injury prevalence, injury pattern, and potential baseline risk factors for injuries in male and female adolescent and adult amateur football players.

METHODS

This prospective study followed adolescent and adult amateur football players over one season March-October 2020. The study was completed by 462 players (130 men, age 20.0 ± 5.7, 14-46 years) who answered a baseline survey and a weekly web survey during the season. A total of 1456 weekly surveys were registered from males and 5041 from females. Injuries were recorded with the Oslo Sports Trauma Research Center Overuse Injury Questionnaire (OSTRC-O2). Potential baseline risk factors (age, performance of strength/conditioning training, participation in other sports, perceived importance of sporting success, self-rated training and match load, perceived balance between training/match load and recovery, previous/present injury at start of season, and injury beliefs) and their association with injury were analysed with Poisson regressions within each sex.

RESULTS

Males reported 95 injuries (262 injury weeks, weekly prevalence 18.0% (95% CI 16.1-20.1)) and females 350 injuries (1206 injury weeks, weekly prevalence 23.9% (95% CI 22.8-25.1)). Gradual-onset injuries accounted for 57% of the injuries in males and 66% in females. For males, substantial injuries were most common in the hip/groin (weekly prevalence 3.8%), ankle (2.1%), posterior thigh (2.0%), and knee (2.0%); and for females, in the knee (4.3%), ankle (2.5%), and lower leg/Achilles tendon (2.0%). Significant risk factors for injury were higher age (rate ratio males 1.05 per year increase (95% CI 1.02-1.08), females 1.03 (95% CI 1.01-1.05)), and present injury at baseline (males 1.92 (95% CI 1.27-2.89), females 1.58 (95% CI 1.19-2.09)).

CONCLUSION

At any given week, almost one in five male and one in four female amateur football players reported new or ongoing injuries. Hip/groin injuries were more frequent in males, while female players had a higher prevalence of knee injuries. Older players and those with an existing injury at the start of the season were more prone to new injury during the season. Rehabilitation of pre-season injury and complaints are key to reduce the injury burden in amateur football.

LEVEL OF EVIDENCE

Level II. Trial registration number NCT04272047, Clinical trials.

Risk Factors for Sustaining a Second ACL Injury after Primary ACL Reconstruction in Female Football Players: A Study Investigating the Effects of Follow-Up Time and the Statistical Approach

BACKGROUND

Studies evaluating risk factors for sustaining an anterior cruciate ligament (ACL) injury have different, sometimes contrasting, results. Different follow-up times and statistical approaches may be a reason for these differences. The aim of this study was to explore if different follow-up times and statistical approaches, classification and regression tree (CART) analysis and Cox regression, would impact on the association between various candidate risk factors and ACL injury in female football players. In total, 112 active female football players, 18 ± 8 months after ACL reconstruction (mean age ± SD, 20 ± 2 years), were included and followed for at least 36 months. At baseline, all players underwent assessment of range of motion of knee and ankle joints, functional tests, and answered questionnaires regarding knee function, psychological and personality traits. Nineteen independent variables were included for the CART analysis and for univariable Cox regression and compared using four different follow-up times: 0-12, 0-24, 0-36, and 0->36 months.

RESULTS

Forty-three (38%) players sustained a second ACL injury. The identified risk factors varied depending on follow-up time both with CART analysis and with Cox regression. CART identified 12 of the 19 independent variables and selected between 5 and 6 of the variables in the four different follow-up times associated with second ACL injury. The accuracy of the different follow-up times for the CART varied between 86 and 93% with 77-96% sensitivity and 70-81% specificity. Cox regression identified two risk factors: knee extension at 0-36 months and 0->36 months, and time between primary injury and surgery at 0->36 months. The accuracy varied between 54 and 64% with 44-88% sensitivity and 32-71% specificity.

CONCLUSIONS

The identified risk factors associated with a second ACL injury varied depending on the follow-up time and statistical approach used. Thus, in future research on risk factors, the time athletes are followed up and the type of statistical methods used are important to discuss.

Current trends in graft choice for anterior cruciate ligament reconstruction - part I: anatomy, biomechanics, graft incorporation and fixation

Graft selection in anterior cruciate ligament (ACL) reconstruction is critical, as it remains one of the most easily adjustable factors affecting graft rupture and reoperation rates. Commonly used autografts, including hamstring tendon, quadriceps tendon and bone-patellar-tendon-bone, are reported to be biomechanically equivalent or superior compared to the native ACL. Despite this, such grafts are unable to perfectly replicate the complex anatomical and histological characteristics of the native ACL. While there remains inconclusive evidence as to the superiority of one autograft in terms of graft incorporation and maturity, allografts appear to demonstrate slower incorporation and maturity compared to autografts. Graft fixation also affects graft properties and subsequent outcomes, with each technique having unique advantages and disadvantages that should be carefully considered during graft selection.

Angular Velocities and Linear Accelerations Derived from Inertial Measurement Units Can Be Used as Proxy Measures of Knee Variables Associated with ACL Injury

Given the high rates of both primary and secondary anterior cruciate ligament (ACL) injuries in multidirectional field sports, there is a need to develop easily accessible methods for practitioners to monitor ACL injury risk. Field-based methods to assess knee variables associated with ACL injury are of particular interest to practitioners for monitoring injury risk in applied sports settings. Knee variables or proxy measures derived from wearable inertial measurement units (IMUs) may thus provide a powerful tool for efficient injury risk management. Therefore, the aim of this study was to identify whether there were correlations between laboratory-derived knee variables (knee range of motion (RoM), change in knee moment, and knee stiffness) and metrics derived from IMUs (angular velocities and accelerations) placed on the tibia and thigh, across a range of movements performed in practitioner assessments used to monitor ACL injury risk. Ground reaction forces, three-dimensional kinematics, and triaxial IMU data were recorded from nineteen healthy male participants performing bilateral and unilateral drop jumps, and a 90° cutting task. Spearman's correlations were used to examine the correlations between knee variables and IMU-derived metrics. A significant strong positive correlation was observed between knee RoM and the area under the tibia angular velocity curve in all movements. Significant strong correlations were also observed in the unilateral drop jump between knee RoM, change in knee moment, and knee stiffness, and the area under the tibia acceleration curve (r_s = 0.776, r_s = -0.712, and r_s = -0.765, respectively). A significant moderate correlation was observed between both knee RoM and knee stiffness, and the area under the thigh angular velocity curve (r_s = 0.682 and r_s = -0.641, respectively). The findings from this study suggest that it may be feasible to use IMU-derived angular velocities and acceleration measurements as proxy measures of knee variables in movements included in practitioner assessments used to monitor ACL injury risk.

Repeat Anterior Cruciate Ligament Injury and Return to Sport in Australian Soccer Players After Anterior Cruciate Ligament Reconstruction With Hamstring Tendon Autograft

BACKGROUND

Soccer is the most commonly played team sport in the world and a high-risk sport for anterior cruciate ligament (ACL) injury and subsequent ACL reconstruction (ACLR).

PURPOSE

To assess the rate of further ACL injury in patients who have undergone ACLR with hamstring tendon autograft after soccer injuries in Australia and to determine factors associated with repeat ACL injury and return to soccer.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

From a prospectively collected database, a series of 1000 consecutive ACLRs using hamstring autografts performed in soccer players were identified. Patients were surveyed at a minimum 5 years after reconstruction, including details of further ACL injuries to either knee, return to soccer or other sports, and psychological readiness per the Anterior Cruciate Ligament Return to Sport after Injury (ACL-RSI) scale.

RESULTS

Of the 862 participants reviewed, ACL graft rupture occurred in 85 (10%) and contralateral ACL rupture in 68 (8%) within 5 years after the reconstruction. The 5-year ACL graft survivorship was 94% for females and 88% for males. The survivorship of the contralateral ACL was 92% for males and 90% for females. When compared with those aged >25 years, the odds of ACL graft rupture was increased by 4 to 5 times in those aged 19 to 25 years and 3 to 7 times in those ≤18 years. Further ACL injury to the graft or contralateral knee occurred in 44% of males aged ≤18 years. Risk factors for further ACL injury were younger age at time of surgery, male sex, and return to soccer. Graft diameter did not influence ACL graft rupture rates, and 70% of patients returned to soccer after ACLR. The mean ACL-RSI score was 59, and patients who reported more fear of reinjury on this scale were less likely to have returned to soccer.

CONCLUSION

The prevalence of ACL graft rupture (10%) and contralateral ACL rupture (8%) was near equivalent over 5 years in this large cohort of mostly recreational Australian soccer players. ACLR with hamstring autograft is a reliable procedure, allowing 70% of patients to return to soccer in this high-risk population. Risk factors for further ACL injury are progressively younger age at time of surgery, male sex, and return to soccer. Graft diameter was not a factor in ACL graft rupture, indicating that other factors, particularly age, are of primary importance.

Quadriceps tendon autograft for primary anterior cruciate ligament reconstruction show comparable clinical, functional, and patient-reported outcome measures, but lower donor-site morbidity compared with hamstring tendon autograft: A matched-pairs study with a mean follow-up of 6.5 ​years

OBJECTIVES

To compare clinical and functional outcomes of patients after primary anterior cruciate ligament reconstruction (ACLR) using quadriceps tendon- (QT-A) and hamstring tendon (HT-A) autograft with a minimum follow-up (FU) of 5 years.

METHODS

Between 2010 and 2014, all patients undergoing ACLR were recorded in a prospectively administered database. All patients with primary, isolated QT-A ACLR and without any concomitant injuries or high grade of osteoarthritis were extracted from the database and matched to patients treated with HT-A. Re-rupture rates, anterior-posterior (ap) knee laxity, single-leg hop test (SLHT) performance, distal thigh circumference (DTC) and patient-reported outcome measures (PROMs) were recorded. Between group comparisons were performed using chi-square-, independent-samples T- or Mann-Whitney-U tests.

RESULTS

45 QT-A patients were matched to 45 HT-A patients (n ​= ​90). The mean FU was 78.9 ​± ​13.6 months. 18 patients (20.0%/QT-A: N ​= ​8, 17.8%; HT-A: n ​= ​10, 22.2%; p ​= ​.60) sustained a graft rupture and 17 subjects (18.9%/QT-A: n ​= ​9, 20.0%; HT-A: n ​= ​8, 17.8%; p ​= ​.79) suffered a contralateral ACL injury. In high active patients (Tegner activity level ≥ 7) rerupture rates increased to 37.5% (HT-A) and 22.2% (QT-A; p ​= ​.32), respectively. Patients with graft failure did not differ between both groups in terms of mean age at surgery (QT-A: 26.5 ​± ​11.6 years, HT-A: 23.3 ​± ​9.5 years, p ​= ​.63) or graft thickness (mean graft square area: QT-A: 43.6 ​± ​4.7 mm², HT-A: 48.1 ​± ​7.9 mm², p ​= ​.27). No statistical between-group differences were found in ap knee laxity side-to-side (SSD) measurements (QT-A: 1.9 ​± ​1.2 ​mm, HT-A: 2.1 ​± ​1.5 ​mm; p ​= ​.60), subjective IKDC- (QT-A: 93.8 ​± ​6.8, HT-A: 91.2 ​± ​7.8, p ​= ​.17), Lysholm- (QT-A 91.9 ​± ​7.2, HT-A: 91.5 ​± ​9.7, p ​= ​.75) or any of the five subscales of the KOOS score (all p ​> ​.05). Furthermore, Tegner activity level (QT-A: 6(1.5), HT-A: 6(2), p ​= ​.62), VAS for pain (QT-A: 0.5 ​± ​0.9, HT-A: 0.6 ​± ​1.0, p ​= ​.64), Shelbourne-Trumper score (QT-A: 96.5 ​± ​5.6, HT-A: 95.2 ​± ​8.2, p ​= ​.50), Patient and Observer Scar -Assessment scale (POSAS) (QT-A: 9.4 ​± ​3.2, HT-A: 10.7 ​± ​4.9, p ​= ​.24), SSD-DTC (QT-A: 0.5 ​± ​0.5, HT.- A: 0.5 ​± ​0.6, p ​= ​.97), return to sports rates (QT-A: 82.1%, HT-A: 86.7%) and SLHT (QT -A: 95.9 ​± ​3.8%, HT-A: 93.7 ​± ​7.0%) did not differ between groups. Donor-site morbidity (HT-A n ​= ​14, 46.7%; QT-A n ​= ​3, 11.5%; p ​= ​.008) was statistically significantly lower in the QT-A group. Five patients (11.1%) of the HT-group and three patients (6.7%) in the QT-group required revision surgery (p ​= ​.29).

CONCLUSION

Patient-reported outcome measures, knee laxity, functional testing results and re-rupture rates are similar between patients treated with QT- and HT- autografts. However, patients with QT-autograft have a smaller tibial postoperative scar length and lower postoperative donor-site morbidity. There is a tendency towards higher graft rupture rates in highly active patients treated with HT autograft.

LEVEL OF EVIDENCE

II.

Comparable Instrumented Knee Joint Laxity and Patient-Reported Outcomes After ACL Repair With Dynamic Intraligamentary Stabilization or ACL Reconstruction: 5-Year Results of a Randomized Controlled Trial

BACKGROUND

Technical innovation has led to the renaissance of anterior cruciate ligament (ACL) repair in the past decade.

PURPOSE/HYPOTHESIS

The present study aimed to compare instrumented knee joint laxity and patient-reported outcomes (PROs) after ACL repair with those after primary ACL reconstruction for acute isolated ACL tears. It was hypothesized that ACL repair would lead to comparable knee joint stability and PROs at 5 years postoperatively in comparison with ACL reconstruction.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 85 patients with acute ACL tears were randomized to undergo either ACL repair using dynamic intraligamentary stabilization (DIS) or primary ACL reconstruction with a semitendinosus tendon autograft. The primary outcome was the side-to-side difference in anterior tibial translation (ΔATT) assessed by Rolimeter testing at 5 years postoperatively. Follow-up examinations were performed at 1, 2, and 5 years. PROs were assessed using the Tegner activity scale, the International Knee Documentation Committee (IKDC) subjective score, and the Lysholm score. Furthermore, the rates of recurrent instability, other complications, and revision surgery were recorded. A power analysis was performed a priori, and the Friedman test, Mann-Whitney U test, and Bonferroni correction were applied for statistical comparisons with significance set at P < .05.

RESULTS

The mean age at inclusion was 28.3 ± 11.5 years in the ACL repair group and 27.1 ± 11.5 years in the ACL reconstruction group. At 5 years postoperatively, a total of 64 patients (ACL repair: n = 34 of 43 [79%]; ACL reconstruction: n = 30 of 42 [71%]) were available for follow-up. At 5 years, ΔATT was 1.7 ± 1.6 mm in the ACL repair group and 1.4 ± 1.3 mm in the ACL reconstruction group (P = .334). Preinjury PROs were restored as soon as 1 year after surgery and plateaued until 2 and 5 years postoperatively in both groups. At the 5-year follow-up, the mean Lysholm score was 97.0 ± 5.4 versus 94.5 ± 5.5 (P = .322), respectively, and the mean IKDC subjective score was 94.1 ± 9.9 versus 89.9 ± 7.8 (P = .047), respectively, in the ACL repair group versus ACL reconstruction group. At 5 years postoperatively, 12 patients in the ACL repair group (35%; age <25 years: n = 10/12; Tegner score ≥7: n = 10/12) had recurrent instability, of whom 10 underwent single-stage revision ACL reconstruction. In the ACL reconstruction group, there were 6 patients with recurrent instability (20%; age <25 years: n = 6/6; Tegner score ≥7: n = 5/6); however, in 5 patients, staged revision was required. Differences between both groups regarding recurrent instability (P = .09) or ACL revision surgery (P = .118) were not statistically significant. Recurrent instability was associated with age <25 years and Tegner score >7 in both groups.

CONCLUSION

At 5 years after ACL repair with DIS, instrumented knee joint laxity and PROs were comparable with those after ACL reconstruction. Although no significant difference was found between repair and reconstruction, a critical appraisal of the rates of recurrent instability (35% vs 20%, respectively) and revision surgery (38% vs 27%, respectively) is needed. Young age and a high preinjury activity level were the main risk factors for recurrent instability in both groups. However, single-stage revision ACL reconstruction was possible in each case in the ACL repair group. Although ACL reconstruction remains the gold standard in the treatment of ACL tears, the present study supports the use of ACL repair with DIS as a feasible option to treat acute ACL tears in patients aged ≥25 years with low to moderate activity levels (Tegner score <7).

REGISTRATION

DRKS00015466 (German Clinical Trials Register).

Risk Factors for Anterior Cruciate Ligament Graft Failure in Professional Athletes: An Analysis of 342 Patients With a Mean Follow-up of 100 Months From the SANTI Study Group

BACKGROUND

Anterior cruciate ligament (ACL) injuries are among the most common knee injuries sustained in elite sport, and athletes generally undergo ACL reconstruction (ACLR) to facilitate their return to sport. ACL graft rupture is a career-threatening event for elite athletes.

PURPOSE/HYPOTHESIS

The purpose of this study was to determine the risk factors for graft failure in professional athletes undergoing ACLR. It was hypothesized that athletes who underwent combined ACLR with a lateral extra-articular procedure (LEAP) would experience significantly lower rates of graft rupture in comparison with those who underwent isolated ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Professional athletes who underwent primary ACLR with a minimum follow-up of 2 years were identified from the Santy database. Patients were excluded if they underwent major concomitant procedures, including multiligament reconstruction surgery or osteotomy. Further ipsilateral knee injury, contralateral knee injury, and any other reoperations or complications after the index procedure were identified by interrogation of the database and review of the medical notes.

RESULTS

A total of 342 athletes with a mean follow-up of 100.2 ± 51.9 months (range, 24-215 months) were analyzed. Graft failures totaling 31 (9.1%) were reported, requiring revision surgery because of symptomatic instability. The rate of graft failure was significantly higher when ACLR was not combined with a LEAP (15.5% vs 6.0%; P = .0105) and in athletes aged 21 years or younger (13.8% vs 6.6%; P = .0290). A multivariate analysis was performed using the Cox model and demonstrated that athletes undergoing an isolated ACLR were at >2-fold risk of ACL graft rupture (hazard ratio [HR], 2.678 [1.173; 4.837], P = .0164) when compared with those undergoing a combined ACLR with a LEAP. Additionally, athletes aged ≤21 years were also at >2-fold risk of graft failure (HR, 2.381 [1.313; 5.463]; P = .0068) than those aged >21 years. Sex, sport, and graft type were not found to be significant risk factors for graft failure.

CONCLUSION

Professional athletes undergoing isolated ACLR and aged ≤21 years are at >2-fold greater risk of graft failure. Orthopaedic surgeons treating elite athletes should combine an ACLR with a LEAP to improve ACL graft survivorship.

Biomechanical asymmetries differ between autograft types during unplanned change of direction after ACL reconstruction

Nine months after anterior cruciate ligament (ACL) reconstruction, athletes who undergo surgery using a bone-patellar-tendon-bone (BPTB) autograft demonstrate higher loading asymmetries during vertical jumping than those with a hamstring tendon (HT) autograft. These asymmetries may transfer into sporting movements with a greater ACL injury risk. The aim of this study was to compare between-limb asymmetries in knee mechanics and task performance during an unplanned 90° change-of-direction (CoD) task in male field sport athletes reconstructed with BPTB or HT autografts. Seventy-eight male multidirectional field sport athletes with either a BPTB (n = 39) or HT (n = 39) autograft completed maximal unplanned CoD trials in a three-dimensional motion capture laboratory at approximately 9 months post-surgery. A mixed-model 2x2 ANOVA (autograft type x limb) was used to compare variables related to ACL injury risk (e.g., internal knee moments) and performance (e.g., completion time) between autografts and limbs. Statistical parametric mapping was used for a waveform comparison throughout stance, supplemented with a discrete point analyses of peak knee moments and performance variables. Interaction effects were found at the knee joint, with BPTB demonstrating greater asymmetries than HT in knee extension moment (p < 0.001); resultant ground reaction force (p < 0.001); peak knee external rotation moment (p = 0.04); and knee adduction (p = 0.05), medial rotation (p < 0.001), and flexion (p < 0.001) angles. No differences were found between autografts for any performance variable. BPTB demonstrated greater lower-limb biomechanical asymmetries than HT during CoD, which may influence knee loading and longer-term outcomes and should thus be targeted during rehabilitation prior to return to play.

Current trends in the anterior cruciate ligament part II: evaluation, surgical technique, prevention, and rehabilitation

Clinical evaluation and management of anterior cruciate ligament (ACL) injury is one of the most widely researched topics in orthopedic sports medicine, giving providers ample data on which to base their practices. The ACL is also the most commonly treated knee ligament. This study reports on current topics and research in clinical management of ACL injury, starting with evaluation, operative versus nonoperative management, and considerations in unique populations. Discussion of graft selection and associated procedures follows. Areas of uncertainty, rehabilitation, and prevention are the final topics before a reflection on the current state of ACL research and clinical management of ACL injury. Level of evidence V.