Reference Values for the Marx Activity Rating Scale in a Young Athletic Population: History of Knee Ligament Injury Is Associated With Higher Scores

Using 3D MRI Bone Shape to Predict Pre-Osteoarthritis of the Knee 2 Years After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Anterior cruciate ligament (ACL) injury increases risks for osteoarthritis (OA), a poorly modifiable and disabling condition. Joint changes of potentially reversible pre-OA have been described just 2 years after ACL reconstruction (ACLR) when early bone shape changes have also been reported.

PURPOSE

This study evaluates relationships between interlimb differences in tibiofemoral bone shape derived from statistical shape modeling (SSM) of magnetic resonance imaging (MRI) and participant factors on patient-reported outcomes 2 years after unilateral ACLR.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

SSM-derived tibiofemoral bone shape and subchondral bone area were assessed from bilateral knee MRI scans of 72 participants with unilateral ACLR (mean age, 34 ± 11 years; 32 women) and compared with a reference cohort of 398 older individuals without OA (mean age, 50 ± 3 years; 213 women). Multivariable logistic regression models examined relationships between participant and surgical factors with interlimb differences in bone shapes or subchondral bone areas. Relationships between patient-reported outcomes and the interlimb differences in bone shape and subchondral area were examined using similar models.

RESULTS

Bone shape scores and subchondral bone areas were greater (more OA-like) in ACLR knees than uninjured contralateral knees in every bone metric tested (P≤ .001). Interlimb differences in femur shape scores of participants with ACLR were 65% greater (P < .001) than those of the significantly older reference cohort. Taller height, medial meniscal tears, and decreasing age were associated with larger interlimb differences in shape scores and subchondral areas (P < .05). Bone-patellar tendon-bone (BPTB) autograft recipients demonstrated greater interlimb subchondral area differences compared with allograft recipients (P < .05). Interlimb differences for hamstring autograft recipients did not differ from those with BPTB or allograft. Greater interlimb differences in medial femur subchondral areas were associated with worse patient-reported Knee injury and Osteoarthritis Outcome Score Symptoms (R = 0.27; P = .040).

CONCLUSION

Even in the absence of radiographic OA, just 2 years after unilateral ACLR patients showed greater bone shape scores and subchondral areas consistent with pre-OA in their ACLR knees. Furthermore, greater medial femur bone areas were weakly associated with worse symptoms. Patients who are younger, are taller, have meniscal tears, or have BPTB grafts may be at increased risk for bony asymmetries 2 years after ACLR.

Predictors of Return to Activity at 2 Years After Anterior Cruciate Ligament Reconstruction Among Patients With High Preinjury Marx Activity Scores: A MOON Prospective Cohort Study

BACKGROUND

Predictors of return to activity after anterior cruciate ligament reconstruction (ACLR) among patients with relatively high preinjury activity levels remain poorly understood.

PURPOSE/HYPOTHESIS

The purpose of this study was to identify predictors of return to preinjury levels of activity after ACLR, defined as achieving a Marx activity score within 2 points of the preinjury value, among patients with Marx activity scores of 12 to 16 who had been prospectively enrolled in the Multicenter Orthopaedic Outcomes Network (MOON) cohort. We hypothesized that age, sex, preinjury activity level, meniscal injuries and/or procedures, and concurrent articular cartilage injuries would predict return to preinjury activity levels at 2 years after ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

All unilateral ACLR procedures from 2002 to 2008 performed in patients enrolled in the MOON, with preinjury Marx activity scores ranging from 12 to 16, were evaluated with a specific focus on return to preinjury activity levels at 2 years postoperatively. Return to activity was defined as a Marx activity score within 2 points of the preinjury value. The proportion of patients able to return to preinjury activity levels was calculated, and multivariable modeling was performed to identify risk factors for patients' inability to return to preinjury activity levels.

RESULTS

A total of 1188 patients were included in the final analysis. The median preinjury Marx activity score was 16 (interquartile range, 12-16). Overall, 466 patients (39.2%) were able to return to preinjury levels of activity, and 722 patients (60.8%) were not able to return to preinjury levels of activity. Female sex, smoking at the time of ACLR, fewer years of education, lower 36-Item Short Form Health Survey Mental Component Summary scores, and higher preinjury Marx activity scores were predictive of patients' inability to return to preinjury activity levels. Graft type, revision ACLR, the presence of medial and/or lateral meniscal injuries, a history of meniscal surgery, the presence of articular cartilage injuries, a history of articular cartilage treatment, and the presence of high-grade knee laxity were not predictive of a patient's ability to return to preinjury activity level.

CONCLUSION

At 2 years after ACLR, most patients with high preinjury Marx activity scores did not return to their preinjury level of activity. The higher the preinjury Marx activity score that a patient reported at the time of enrollment, the less likely he/she was able to return to preinjury activity level. Smoking and lower mental health at the time of ACLR were the only modifiable risk factors in this cohort that predicted an inability to return to preinjury activity levels. Continued effort and investigation are required to maximize functional recovery after ACLR in patients with high preinjury levels of activity.

Sex-Specific Brain Activations during Single-Leg Exercise

Background

Females have an increased incidence of musculoskeletal injuries compared to males. Sex differences in neuromuscular control has been widely studied regarding the dynamics and muscle activity during preplanned movements. While muscle activation patterns and movement biomechanics are understood to differ between sexes, it is not well understood how sex influences brain activity for lower extremity movement. Since the brain plays a vital role for voluntary movement and joint stability, it is important to understand the sex differences in brain function in order to better understand neuromuscular control associated with increased musculoskeletal injury risk in female.

Hypothesis/Purpose

The purpose of this study is to understand the differences in brain activation patterns between sexes during a simple active knee extension-flexion movement. It was hypothesized that females would demonstrate higher cortical activation in the somatosensory areas compared to males as a compensatory strategy.

Study Design

Cross-Sectional Study.

Methods

Thirteen males and seventeen females who were healthy and physically active participated in this study (Male: 23.7±3.8 years, 74.5±13.5 kg, 172.3±6.4 cm; Female: 20.6±1.6 years, 65.4±12.8 kg, 163±6.1 cm). Functional magnetic resonance imaging data were obtained during a simple left knee extension-flexion exercise with their own leg weight while lying on the MRI table. The blood oxygen level dependent (BOLD) signals were compared between sexes.

Results

There was significantly greater activation in the visual cortices and premotor cortex in females compared to males during the studied movement. Males demonstrated significantly greater activation in the right cerebellum.

Conclusion

The results revealed sex differences in BOLD signal during simple knee extension-flexion movement. The results suggest that sex may be a biological factor in understanding brain activity associated with knee motor control.

Level of Evidence

Level 3.

Harvesting a second graft from the extensor mechanism for revision ACL reconstruction does not delay return of quadriceps function

PURPOSE

The purpose of this study was to evaluate whether harvesting a second graft from the ipsilateral extensor mechanism adversely affects clinical outcomes in revision anterior cruciate ligament (ACL) reconstruction.

METHODS

A retrospective review of 34 patients undergoing revision anterior cruciate ligament (ACL) reconstruction with either quadriceps tendon (QT) autograft or bone-tendon-bone (BTB) autograft was conducted. Patients with two grafts (BTB+QT) from the extensor mechanism were matched based on age, laterality, and sex to patients who had primary reconstruction with hamstring (HS) autograft followed by revision with either BTB or QT autograft (HS+QT/BTB). Return of quadriceps function was assessed with time to return to jogging in a standardized rehab protocol or time to regain 80% quadriceps strength. Secondary outcomes included International Knee Documentation Committee (IKDC) and Marx scores at 12-month follow-up and return to sport.

RESULTS

There were no significant differences in return to jogging or 80% quadriceps strength (HS 149.5 ± 38.2 days, BTB+QT 131.7 ± 40.1 days, n.s.), number able to return to sport (HS 62%, BTB+QT 93%, n.s.), months to return to sport (HS 10.6 ± 1.4, BTB+QT 10.5 ± 2.3, n.s.), return to pre-injury level of competition (HS 62%, BTB+QT 73%, n.s.), or IKDC (HS 77.2 ± 16.4, BTB+QT 74.8 ± 23.9, n.s.) and Marx scores (HS 9.2 ± 5.3, BTB+QT 8.0 ± 3.7, n.s.) at one-year follow-up.

CONCLUSION

The main finding of the present study was that outcomes for patients who underwent revision ACL reconstruction with a second extensor mechanism autograft were comparable to those seen for patients who underwent revision ACL reconstruction with extensor mechanism autograft after primary ACL reconstruction with hamstring autograft. By better understanding the consequences of harvesting a second graft from the extensor mechanism, surgeons can better decide what graft to use in revision ACL reconstruction.

LEVEL OF EVIDENCE

Level III.

Long-Term Outcomes of Multiligament Knee Injuries

OBJECTIVE

To characterize long-term outcomes of multiligament knee injuries (MLKIs) using patient-reported outcome measures, physical examination, and knee radiographs.

DESIGN

Retrospective clinical follow-up.

METHODS

Twenty knees (18 patients) were evaluated at a mean follow-up of 13.1 years (range 11-15 years). The primary outcome measure was the Internal Knee Documentation Committee score. Patients also completed secondary patient-based outcome assessments including Patient-Reported Outcomes Measurement Information System computer adaptive testing, Short Form-36, and Tegner activity score. Sixteen knees (14 patients) also had physical examination and bilateral knee radiographs assessed with the Kellgren-Lawrence score.

RESULTS

The mean Internal Knee Documentation Committee score was 56 points, which was significantly lower than the age-matched normative value of 77 ( P = 0.004) and exceeds the minimum clinically important difference of 12 points. Most secondary outcome scores were worse than normative population values. Posttraumatic arthritis was present in 100% of MLKIs that had radiographs. Comparing operative versus nonoperative management, there were no statistical differences in patient demographics, injury characteristics, physical examination, or imaging, but surgical patients had better Short Form-36 Social Functioning (89 vs. 63, P = 0.02) and Tegner scores (4.5 vs. 2.9, P = 0.05).

CONCLUSION

The long-term outcomes of MLKIs are generally poor, and posttraumatic radiographic evidence of arthritis seems to be universal . Operative management of these injuries may improve long-term outcomes. Clinicians should be aware of these results when counseling patients.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Scoping Review on ACL Surgery and Registry Data

Purpose of Review

To present an overview of registry-based anterior cruciate ligament (ACL) research, as well as provide insight into the future of ACL registries.

Recent Findings

During the past decades, the ACL registries have had an important role in increasing our understanding of patients with ACL injuries and their treatment. The registry data has deepened our understanding of factors that have been associated with an increased risk of sustaining an ACL injury and for evaluation of treatment factors and their impact on patient-related outcomes. Recently, registry-based ACL research using artificial intelligence (AI) and machine learning (ML) has shown potential to create clinical decision-making tools and analyzing outcomes. Thus, standardization of collected data between the registries is needed to facilitate the further collaboration between registries and to facilitate the interpretation of results and subsequently improve the possibilities for implementation of AI and ML in the registry-based research.

Summary

Several studies have been based on the current ACL registries providing an insight into the epidemiology of ACL injuries as well as outcomes following ACL reconstruction. However, the current ACL registries are facing future challenges, and thus, new methods and techniques are needed to ensure further good quality and clinical applicability of study findings based on ACL registry data.

Return to Sports After Anterior Cruciate Ligament Reconstruction: Validity and Reliability of the SPORTS Score at 6 and 12 Months

Background:

The Subjective Patient Outcome for Return to Sports (SPORTS) score is a single-item scale that measures athletes' ability to return to their preinjury sport based on effort and performance.

Purpose/Hypothesis:

The purpose of this study was to examine the psychometric properties of the SPORTS score and a modified score within the first year after anterior cruciate ligament reconstruction (ACLR). The modified version replaced “same sport” with “any sport” in the answer choices. It was hypothesized that both versions of the SPORTS score would have acceptable floor and ceiling effects and internal responsiveness, moderate convergent validity, and excellent test-retest reliability.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

Patients were recruited preoperatively from 2 academic medical centers. The authors collected responses to the 1-item SPORTS scores at 6 and 12 months after ACLR and the Tegner activity scale, Lysholm knee score, Knee injury and Osteoarthritis Outcome Score (KOOS)–sport/recreation subscale, and Marx activity rating scale preoperatively and 6 and 12 months after ACLR. Ceiling and floor effects and responsiveness were assessed using descriptive statistics and cross-tabulations, respectively, at both follow-up time points. Spearman correlations and intraclass correlation coefficients were used to examine convergent validity and test-retest reliability, respectively.

Results:

Follow-up rates at 6 and 12 months were 100% and 99%, respectively. Test-retest follow-up was 77%. Floor effects for the SPORTS scores were not observed, while ceiling effects at 12 months ranged from 38% to 40%. Cross-tabulation of the SPORTS scores showed that 64% to 66% of patients reported a change in their score from 6 to 12 months, with significant differences noted between the proportions that improved versus worsened for return to any sport. Convergent validity was observed at 6 and 12 months via moderate correlations with the Tegner, Lysholm, KOOS–sport/recreation, and Marx scores (r = 0.31 to 0.47). Fair to good test-retest reliability (intraclass correlation coefficient, 0.58 and 0.60) was found at 12 months after ACLR.

Conclusion:

The SPORTS score appears to be a reliable, responsive, and valid 1-item scale that can be used during the first year after ACLR. No differences in psychometric properties were found between the SPORTS score and the modified version.

ACL Size, but Not Signal Intensity, Is Influenced by Sex, Body Size, and Knee Anatomy

Background:

Little is known about sex-based differences in anterior cruciate ligament (ACL) tissue quality in vivo or the association of ACL size (ie, volume) and tissue quality (ie, normalized signal intensity on magnetic resonance imaging [MRI]) with knee anatomy.

Hypothesis:

We hypothesized that (1) women have smaller ACLs and greater ACL normalized signal intensity compared with men, and (2) ACL size and normalized signal intensity are associated with age, activity levels, body mass index (BMI), bicondylar width, intercondylar notch width, and posterior slope of the lateral tibial plateau.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Knee MRI scans of 108 unique ACL-intact knees (19.7 ± 5.5 years, 62 women) were used to quantify the ACL signal intensity (normalized to cortical bone), ligament volume, mean cross-sectional area, and length. Independent t tests were used to compare the MRI-based ACL parameters between sexes. Univariate and multivariate linear regression analyses were used to investigate the associations between normalized signal intensity and size with age, activity levels, BMI, bicondylar width, notch width, and posterior slope of the lateral tibial plateau.

Results:

Compared with men, women had significantly smaller mean ACL volume (men vs women: 2028 ± 472 vs 1591 ± 405 mm³), cross-sectional area (49.4 ± 9.6 vs 41.5 ± 8.6 mm²), and length (40.8 ± 2.8 vs 38.1 ± 3.1 mm) (P < .001 for all), even after adjusting for BMI and bicondylar width. There was no difference in MRI signal intensity between men and women (1.15 ± 0.24 vs 1.12 ± 0.24, respectively; P = .555). BMI, bicondylar width, and intercondylar notch width were independently associated with a larger ACL (R² > 0.16, P < .001). Younger age and steeper lateral tibial slope were independently associated with shorter ACL length (R² > 0.03, P < .04). The combination of BMI and bicondylar width was predictive of ACL volume and mean cross-sectional area (R² < 0.3). The combination of BMI, bicondylar width, and lateral tibial slope was predictive of ACL length (R² = 0.39). Neither quantified patient characteristics nor anatomic variables were associated with signal intensity.

Conclusion:

Men had larger ACLs compared with women even after adjusting for BMI and knee size (bicondylar width). No sex difference was observed in signal intensity, suggesting no difference in tissue quality. The association of the intercondylar notch width and lateral tibial slope with ACL size suggests that the influence of these anatomic features on ACL injury risk may be partially explained by their effect on ACL size.

Registration:

NCT02292004 and NCT02664545 (ClinicalTrials.gov identifier).

Anatomic all-epiphyseal ACL reconstruction with "inside-out" femoral tunnel placement in immature patients yields high return to sport rates and functional outcome scores a minimum of 24 months after reconstruction

PURPOSE

To understand if anatomic physeal-sparing ACL reconstruction in the immature host preserves range of motion, permits a return to sports, and avoids limb length discrepancy and accelerated intra-articular degeneration with a cross-sectional radiographic, physical examination and patient-reported outcomes analysis.

METHODS

A cross-sectional recall study included 38 patients aged 7-15 who underwent all-epiphyseal ACL reconstruction with hamstring allograft performed by a single surgeon at a large academic medical center. All-epiphyseal reconstructions were performed using a modified Anderson physeal-sparing technique, with the femoral tunnel placed using an "inside-out" technique. Assessments consisted of a physical exam, long leg cassette radiographs, KT-1000 measurements, subjective patient metrics, and magnetic resonance imaging.

RESULTS

Thirty-eight (56.7%) of 66 eligible patients returned for in-person clinical and radiographic exams. Patients were 11.4 ± 1.8 years at the time of surgery. Five patients were females (13.2%). Mean follow-up was 5.5 ± 2.4 years. ACL re-injuries occurred in four patients (10.5%), all of whom underwent revision reconstructions. Thirty-three of the remaining 34 (97.1%) patients returned to sports following their reconstruction, and 24 (70.6%) returned to their baseline level of competition. Mean limb length discrepancy (LLD) was 0.2 ± 1.4 cm. Nine patients had an LLD of > 1 cm (26.5%), which occurred at an equivalent age as those with < 1 cm LLD (10.8 ± 2.0 vs. 11.7 ± 1.7, n.s.). Pre-operative Marx scores (13.1 ± 3.5) were not significantly different from post-operative values (12.3 ± 5.1, n.s.). Patients who required ACL revisions had significantly lower Marx scores than those with intact primary grafts (8.3 ± 7.1 vs. 13.4 ± 4.5, p = 0.047). Cohort mean International Knee Documentation Committee (IKDC) score was 89.7 ± 12.7.

CONCLUSION

Anatomic all-epiphyseal anatomic ACL reconstruction appears to be useful in patients with significant projected remaining growth, with good return-to-sport outcomes and minimal risk of clinically significant physeal complications. However, given the limited patient recall possible in the present study, further large sample size, high-quality works are necessary to validate our findings.

LEVEL OF EVIDENCE

Level IV.

PROMIS Versus Legacy Patient-Reported Outcome Measures for Sports Medicine Patients Undergoing Arthroscopic Knee, Shoulder, and Hip Interventions: A Systematic Review

BACKGROUND

The Patient-Reported Outcomes Measurement Information System (PROMIS®) was designed to monitor the global wellbeing of patients, with the Physical Function Computer-Adaptive Test (PF-CAT) component focused specifically on functional outcome. PROMIS aims for increased item-bank accuracy, lower administrative burden, and decreased floor and ceiling effects compared to legacy patient-reported outcome measures (PROMs). Our primary research outcomes focused on sports medicine surgical populations, which may skew younger or have wide-ranging functional statuses. Specifically, for this population, we questioned if PROMIS PF-CAT was equal to legacy PROMs in (1) construct validity and (2) convergent/divergent validities; and superior to legacy PROMs with respect to (3) survey burden and (4) floor and ceiling effects.

METHODS

Searches were performed in April 2019 in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, utilizing PubMed, Cochrane Central, and Embase databases for Level I-III evidence. This resulted in 541 records, yielding 12 studies for inclusion. PROM data was available for patients undergoing arthroscopic orthopaedic procedures of the knee, shoulder, and hip. Measures of construct validity, convergent/divergent validity, survey burden, and floor/ceiling effects were evaluated for PROMIS PF-CAT versus legacy PROMs.

RESULTS

PROMIS PF-CAT demonstrated excellent or excellent-good correlation with legacy PROMS for physical function and quality of life for patients undergoing arthroscopic interventions of the knee, shoulder, and hip. Compared to legacy PROM instruments, PROMIS PF-CAT demonstrated the lowest overall survey burden and had the lowest overall number of floor or ceiling effects across participants.

CONCLUSION

PROMIS PF-CAT is an accurate, efficient evaluation tool for sports medicine surgical patients. PROMIS PF-CAT strongly correlates with legacy physical function PROMs while having a lower test burden and less incidence of floor and ceiling effects. PROMIS PF-CAT may be an optimal alternative for traditional physical function PROMs in sports medicine patients undergoing arthroscopic procedures. Further studies are required to extend the generalizability of these findings to patients during postoperative timepoints after shoulder and hip interventionsLevel of Evidence: III.

Terminal knee extension deficit and female sex predict poorer quadriceps strength following ACL reconstruction using all-soft tissue quadriceps tendon autografts

PURPOSE

The all-soft tissue quadriceps tendon (QT) autograft is becoming increasingly popular for ACL reconstruction (ACLR); however, studies reporting strength recovery and early outcomes after QT autograft are limited with patient samples composed of predominantly males. The primary purpose was to characterize early, sex-specific recovery of strength, range of motion (ROM), and knee laxity in a large cohort of patients undergoing primary ACLR with standardized harvest technique of the all-soft tissue QT autograft. The secondary purpose was to examine the influence of demographic factors and clinical measures on 6-month quadriceps strength.

METHODS

Patients 14-25 years who underwent primary, unilateral ACLR with all-soft tissue QT autografts were prospectively followed. Knee laxity and ROM were collected at 6 weeks, 3 and 6 months; while, quadriceps normalized torques and limb symmetry indices (LSI) were collected at 3 and 6 months using isokinetic dynamometry at 60°/s. Two-way ANOVAs with repeated measures were conducted to determine recovery over time and between sexes. Stepwise linear multiple regressions were conducted to determine predictors of 6-month quadriceps strength.

RESULTS

Three-hundred and twenty patients were included (18 ± 3 years; 156 males:164 females; BMI = 24 ± 4 kg/m²) with no early graft failures within the study period. For strength, there were significant main effects of time (p < 0.001) and sex (p < 0.001), indicating similar improvement from 3 to 6 months with males demonstrating greater quadriceps LSI (6 months: 72.1 vs 63.3%) and normalized strength (6 months: 2.0 vs 1.6 Nm/kg). A significantly higher proportion of females had knee extension ROM deficits ≥ 5° compared to males at 6 weeks (61 vs 39%; p = 0.002). Female sex and 3-month extension ROM deficits were identified as significant predictors of 6-month quadriceps LSI (R² = 0.083; p < 0.001). Female sex, BMI, and 6-week extension ROM deficits were identified as significant predictors of 6-month normalized quadriceps strength (R² = 0.190; p < 0.001).

CONCLUSIONS

Females had decreased quadriceps strength and greater extension ROM deficits at 3 and 6 months following ACLR using all-soft tissue QT autografts. Female sex, higher BMI, and loss of extension ROM were independent predictors of poorer quadriceps strength at 6 months. There were no early graft failures, and laxity remained within normal ranges for both males and females. Surgeons and rehabilitation clinicians should be aware of the increased risk of postoperative loss of extension ROM in females and its implications on quadriceps strength recovery.

LEVEL OF EVIDENCE

III.

A Longitudinal Comparison of Patient-Reported Outcomes Measurement Information System to Legacy Scales in Knee and Shoulder Arthroscopy Patients

PURPOSE

The purpose of this prospective correlational study was to compare the psychometric properties of the Defense and Veterans Pain Rating Scale (DVPRS) and Patient-Reported Outcomes Measurement Information System (PROMIS) scales with those of traditional legacy scales over a longitudinal postoperative period in patients undergoing arthroscopic procedures.

METHODS

Active-duty military personnel undergoing shoulder and knee arthroscopic procedures completed the DVPRS, PROMIS, and legacy scales preoperatively and again at 3 months postoperatively. Rolling correlation coefficients (r_rm) were used to assess the concurrent validity between the DVPRS average pain scores and computer adaptive testing PROMIS scales (Anxiety, Depression, Pain Behavior, Pain Interference, Mobility, Sleep Disturbance, Satisfaction With Social Roles, and Upper Extremity Physical Function) and the legacy scales (American Shoulder and Elbow Surgeons [ASES] scale, Shoulder Activity Scale, International Knee Documentation Committee [IKDC] questionnaire, Single Assessment Numeric Evaluation [SANE], Marx Activity Rating Scale, and Veterans RAND 12-Item Health Survey).

RESULTS

A total of 121 participants completed the scales preoperatively, 80 completed them at 3 months postoperatively, and 59 (49% of participants) completed them at both times. Rolling correlation coefficients between PROMIS Pain Interference (r_rm = -0.41, P = .006), Satisfaction With Social Roles (r_rm = 0.56, P < .001), and Upper Extremity (r_rm = 0.71, P < .001) scores showed acceptable concurrent validity with ASES scores over a longitudinal postoperative period. DVPRS scores (r_rm = -0.69, P = .002) and PROMIS Pain Behavior (r_rm = -0.57, P = .018), Pain Interference (r_rm = -0.71, P = .001), Sleep Disturbance (r_rm = -0.64, P = .005), and Mobility (r_rm = 0.65, P = .005) scores showed acceptable concurrent validity with IKDC scores. There was poor correlation between the PROMIS and DVPRS scores and the Single Assessment Numeric Evaluation, Marx Activity Rating Scale, Shoulder Activity Scale, and Veterans RAND 12-Item Health Survey scores.

CONCLUSIONS

PROMIS scales measuring physical function, pain presentation, and other health domains showed acceptable concurrent validity with ASES and IKDC scores. By integrating the prospective collection of biopsychosocial PROMIS scales into practice, it is possible for clinicians in orthopaedic settings to assess changes in validated patient-reported outcomes to inform patient-centered care planning throughout the postoperative recovery period.

LEVEL OF EVIDENCE

Level II, prospective comparative study (with not all participants completing follow-up).

Michigan Initiative for Anterior Cruciate Ligament Rehabilitation (MiACLR): A Protocol for a Randomized Clinical Trial

OBJECTIVE

Restoring quadriceps muscle strength following anterior cruciate ligament reconstruction (ACLR) may prevent the posttraumatic osteoarthritis that affects over 50% of knees with ACLR. However, a fundamental gap exists in our understanding of how to maximize muscle strength through rehabilitation. Neurological deficits and muscle atrophy are 2 of the leading mechanisms of muscle weakness after ACLR. High-intensity neuromuscular electrical stimulation (NMES) and eccentric exercise (ECC) have been shown to independently target these mechanisms. If delivered in succession, NMES and then ECC may be able to significantly improve strength recovery. The objectives of this study were to evaluate the ability of NMES combined with ECC to restore quadriceps strength and biomechanical symmetry and maintain cartilage health at 9 and 18 months after ACLR.

METHODS

This study is a randomized, double-blind, placebo-controlled, single-center clinical trial conducted at the University of Michigan. A total of 112 participants between the ages of 14 and 45 years and with an anterior cruciate ligament rupture will be included. Participants will be randomly assigned 1:1 to NMES combined with ECC or NMES placebo combined with ECC placebo. NMES or NMES placebo will be delivered 2 times per week for 8 weeks beginning 10 to 14 days postoperatively and will be directly followed by 8 weeks of ECC or ECC placebo delivered 2 times per week. The co-primary endpoints are change from baseline to 9 months and change from baseline to 18 months after ACLR in isokinetic quadriceps strength symmetry. Secondary outcome measures include isometric quadriceps strength, quadriceps activation, quadriceps muscle morphology (cross-sectional area), knee biomechanics (sagittal plane knee angles and moments), indexes of patient-reported function, and cartilage health (T1ρ and T2 relaxation time mapping on magnetic resonance imaging).

IMPACT

The findings from this study might identify an intervention capable of targeting the lingering quadriceps weakness after ACLR and in turn prevent deterioration in cartilage health after ACLR, thereby potentially improving function in this patient population.

Cross-Cultural Adaptation and Validation of the Romanian Marx Activity Rating Scale for Anterior Cruciate Ligament Reconstruction

AIM

We aimed to translate, cross-cultural adapt and validate the Marx activity rating scale (MARS) of the knee for Romanian patients with anterior cruciate ligament (ACL) injury.

METHOD

The original English form was translated according to guidelines. We included patients with ACL injury undergoing reconstruction in two centers over 3 years. Subjects completed the translated MARS, International Knee Documentation Committee (IKDC) subjective knee form and EuroQol EQ5D. The examining physician completed the Tegner Lysholm scale as an objective evaluation. Re-testing was obtained after one month. We used Spearman`s correlation to evaluate construct validity and reproducibility, Cronbach's alpha for internal consistency and intraclass correlation for test-retest reliability.

RESULTS

We collected valid forms from 99 patients (32.1 ± 8.8 years, 64.6% males) during the preoperative evaluation and 45 were re-tested. Significant, very good correlations were found between the MARS and Tegner Lysholm (Spearman's r = 0.712, p < 0.0001) and IKDC (Spearman's r = 0.801, p < 0.0001). Cronbach's alpha was 0.893 at the initial completion and 0.799 at re-test. The intraclass correlation coefficient was 0.895.

CONCLUSIONS

The Romanian-translated MARS is a valid, consistent and reliable physical activity outcome measure in patients with anterior cruciate ligament reconstruction.

No Difference Between Posterolateral Corner Repair and Reconstruction With Concurrent ACL Surgery: Results From a Prospective Multicenter Cohort

Background:

Injuries to the posterolateral corner (PLC) may occur concurrently with anterior cruciate ligament (ACL) injury.

Purpose/Hypothesis:

This study evaluated the outcomes of patients who underwent operative management of PLC injuries concurrently with ACL reconstruction in a prospective multicenter cohort. We hypothesized that there would be no differences in outcomes between patients who were treated with PLC repair and PLC reconstruction.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Patients undergoing ACL reconstruction were enrolled into a prospective longitudinal multicenter cohort between 2002 and 2008. Those with complete 6-year follow-up data (patient-reported outcomes and subsequent surgery information) were identified. Excluded from the study were patients with posterior cruciate ligament injuries. Patients who underwent PLC repair were compared with those who underwent PLC reconstruction with regard to interval from injury to surgery, need for revision surgery, and long-term outcomes at 6 years.

Results:

During the identified time frame, 3026 identified patients underwent primary ACL reconstruction; 34 (1.1%) also underwent concurrent PLC surgery (15 repairs, 19 reconstructions [18 allografts, 1 autograft]). With the numbers available, we did not detect significant differences between groups regarding the rate of meniscal or chondral injuries. Median time to PLC reconstruction was 121 days as compared with 19 days for concurrent ACL reconstruction and PLC repair (P = .01). There were no between-group differences in Marx activity scores prior to surgery (P = .4). At 6-year follow-up, there were no between-group differences in Knee injury and Osteoarthritis Outcome Score (P = .36-.83) or International Knee Documentation Committee score (P = .84); however, patients treated with PLC reconstructions had lower Marx activity scores (4.1 vs 9.4; P = .02). There was 1 ACL revision in the PLC reconstruction group, and 1 of the PLC repairs was revised to a reconstruction during the follow-up period.

Conclusion:

Good outcomes were achieved at 6-year follow-up with both repair and reconstruction of PLC injuries treated concurrently with ACL reconstruction. The PLC reconstruction group had lower activity levels 6 years after surgery. The present data suggest that, for appropriately selected patients undergoing acute surgical treatment of combined ACL and PLC injuries, PCL repair can achieve good long-term outcomes.

Sex Comparisons of In Vivo Anterior Cruciate Ligament Morphometry

CONTEXT

Females have consistently higher anterior cruciate ligament (ACL) injury rates than males. The reasons for this disparity are not fully understood. Whereas ACL morphometric characteristics are associated with injury risk and females have a smaller absolute ACL size, comprehensive sex comparisons that adequately account for sex differences in body mass index (BMI) have been limited.

OBJECTIVE

To investigate sex differences among in vivo ACL morphometric measures before and after controlling for femoral notch width and BMI.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

Twenty recreationally active men (age = 23.2 ± 2.9 years, height = 180.4 ± 6.7 cm, mass = 84.0 ± 10.9 kg) and 20 recreationally active women (age = 21.3 ± 2.3 years, height = 166.9 ± 7.7 cm, mass = 61.9 ± 7.2 kg) participated.

MAIN OUTCOME MEASURE(S)

Structural magnetic resonance imaging sequences were performed on the left knee. Anterior cruciate ligament volume, width, and cross-sectional area measures were obtained from T2-weighted images and normalized to femoral notch width and BMI. Femoral notch width was measured from T1-weighted images. We used independent-samples t tests to examine sex differences in absolute and normalized measures.

RESULTS

Men had greater absolute ACL volume (1712.2 ± 356.3 versus 1200.1 ± 337.8 mm³; t₃₈ = -4.67, P < .001) and ACL width (8.5 ± 2.3 versus 7.0 ± 1.2 mm; t₃₈ = -2.53, P = .02) than women. The ACL volume remained greater in men than in women after controlling for femoral notch width (89.31 ± 15.63 versus 72.42 ± 16.82 mm³/mm; t₃₈ = -3.29, P = .002) and BMI (67.13 ± 15.40 versus 54.69 ± 16.39 mm³/kg/m²; t₃₈ = -2.47, P = .02).

CONCLUSIONS

Whereas men had greater ACL volume and width than women, only ACL volume remained different when we accounted for femoral notch width and BMI. This suggests that ACL volume may be an appropriate measure of ACL anatomy in investigations of ACL morphometry and ACL injury risk that include sex comparisons.

Biomechanical Responses and Injury Characteristics of Knee Joints under Longitudinal Impacts of Different Velocities

Background and Objective

Knee joint collision injuries occur frequently in military and civilian scenarios, but there are few studies assessing longitudinal impacts on knee joints. In this study, the mechanical responses and damage characteristics of knee longitudinal collisions were investigated by finite element analysis and human knee impact tests.

Materials and methods

Based on a biocollision test plateau, longitudinal impact experiments were performed on 4 human knee joints (2 in the left knee and 2 in the right knee) to measure the impact force and stress response of the bone. And then a finite element model of knee joint was established from the Chinese Visible Human (CVH), with which longitudinal impacts to the knee joint were simulated, in which the stress response was determined. The injury response of the knee joint-sustained longitudinal impacts was analyzed from both the experimental model and finite element analysis.

Results

The impact experiments and finite element simulation found that low-speed impact mainly led to medial injuries and high-speed impact led to both medial and lateral injuries. In the knee joint impact experiment, the peak flexion angles were 13.8° ± 1.2, 30.2° ± 5.1, and 92.9° ± 5.45 and the angular velocities were 344.2 ± 30.8 rad/s, 1510.8 ± 252.5 rad/s, and 9290 ± 545 rad/s at impact velocities 2.5 km/h, 5 km/h, and 8 km/h, respectively. When the impact velocity was 8 km/h, 1 knee had a femoral condylar fracture and 3 knees had medial tibial plateau fractures or collapse fractures. The finite element simulation of knee joints found that medial cortical bone stress appeared earlier than the lateral peak and that the medial bone stress concentration was more obvious when the knee was longitudinally impacted.

Conclusion

Both the experiment and FE model confirmed that the biomechanical characteristics of the injured femur and medial tibia are likely to be damaged in a longitudinal impact, which is of great significance for the prevention and treatment of longitudinal impact injuries of the knee joint.

Change in KOOS and WOMAC Scores in a Young Athletic Population With and Without Anterior Cruciate Ligament Injury

BACKGROUND

Several studies have examined changes in patient-reported outcome measures (PROMs) after anterior cruciate ligament (ACL) injury, but no studies to date have prospectively evaluated changes from preinjury baseline through injury and follow-up among ACL-injured patients compared to the baseline and follow-up changes of uninjured patients.

PURPOSE

To examine changes in PROMs over time from preinjury baseline to at least 2 years after ACL reconstruction and to compare these changes with those of an uninjured control group having similar physical activity requirements.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

The authors conducted a prospective cohort study with a nested case-control analysis at a US service academy. All incoming first year students were recruited to participate in this study. Consenting participants completed a baseline questionnaire that included the KOOS (Knee injury and Osteoarthritis Outcome Score), WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), and MARS (Marx Activity Rating Scale). Participants who sustained a subsequent ACL injury completed assessments at the time of surgery and at 6, 12, and 24 months after surgery. Healthy participants were recruited to repeat the baseline assessments within 1 year of graduation. Inter- and intragroup differences at these time points were evaluated with dependent and independent t tests, respectively. We also compared these results with established minimum clinically important difference (MCID) values.

RESULTS

Of 1268 first year students entering the academy, 1005 with no previous injuries consented to participate in this study (82% male, mean ± SD age 19 ± 1 years). Of those enrolled, 30 suffered an ACL injury and met the inclusion criteria for this study. Ninety uninjured control students who met the inclusion criteria completed follow-up assessments. There were statistically significant differences across all KOOS and WOMAC subscales between ACL-injured group and uninjured group at the time of the final follow-up assessment. Four KOOS subscales (Pain, Symptoms, Sports and Recreation Function, and Knee-Related Quality of Life) and the WOMAC Stiffness subscale demonstrated >8-point differences between groups, which exceeded the established MCID for these instruments. There were no significant differences between the ACL-injured group and uninjured groups noted for the MARS ( P = .635). At the time of final follow-up, the ACL-injured group also reported significant deficits on the WOMAC Stiffness subscale ( P = .032), the MARS ( P = .030), and all KOOS subscales, with the exception of Functional Activities of Daily Living, as compared with their preinjury baseline scores. These deficits exceeded the established MCID values for 3 KOOS subscales and the MARS.

CONCLUSION

Patients with ACL injuries reported significant deficits on PROMs at least 2 years after surgical reconstruction in relation to preinjury baseline scores and an uninjured control group. Many of these deficits exceeded established MCID values.

The Role of Athletic Trainers in Preventing and Managing Posttraumatic Osteoarthritis in Physically Active Populations: a Consensus Statement of the Athletic Trainers' Osteoarthritis Consortium

OBJECTIVE

  To provide athletic trainers with a fundamental understanding of the pathogenesis and risk factors associated with the development of posttraumatic osteoarthritis (PTOA) as well as the best current recommendations for preventing and managing this condition.

BACKGROUND

  Posttraumatic osteoarthritis, or osteoarthritis that develops secondary to joint injury, accounts for approximately 5.5 million US cases annually. A young athlete with a joint injury is at high risk for PTOA before the age of 40, which could lead to the patient living more than half of his or her life with a painful and disabling disorder. Given our frequent contact with physically active people who often sustain traumatic joint injuries, athletic trainers are in a unique position to help prevent and manage PTOA. We can, therefore, regularly monitor joint health in at-risk patients and implement early therapies as necessary.

RECOMMENDATIONS

  The recommendations for preventing and managing PTOA are based on the best available evidence. Primary injury prevention, self-management strategies, maintenance of a healthy body weight, and an appropriate level of physical activity should be encouraged among those at risk for PTOA after acute traumatic joint injury. Education of athletic trainers and patients regarding PTOA is also critical for effective prevention and management of this disease.

PATIENT-SPECIFIC AND SURGERY-SPECIFIC FACTORS THAT AFFECT RETURN TO SPORT AFTER ACL RECONSTRUCTION

CONTEXT

Anterior cruciate ligament (ACL) reconstruction is frequently performed to allow individuals to return to their pre-injury levels of sports participation, however, return to pre-injury level of sport is poor and re-injury rates are unacceptably high. Re-injury is likely associated with the timeframe and guidelines for return to sport (RTS). It is imperative for clinicians to recognize risk factors for re-injury and to ensure that modifiable risk factors are addressed prior to RTS. The purpose of this commentary is to summarize the current literature on the outcomes following return to sport after ACL reconstruction and to outline the biologic and patient-specific factors that should be considered when counseling an athlete on their progression through rehabilitation.

EVIDENCE ACQUISITION

A comprehensive literature search was performed to identify RTS criteria and RTS rates after ACL reconstruction with consideration paid to graft healing, anatomic reconstruction, and risk factors for re-injury and revision. Results were screened for relevant original research articles and review articles, from which results were summarized.

STUDY DESIGN

Clinical Review of the Literature.

RESULTS

Variable RTS rates are presented in the literature due to variable definitions of RTS ranging from a high threshold (return to competition) to low threshold (physician clearance for return to play). Re-injury and contralateral injury rates are greater than the risk for primary ACL injury, which may be related to insufficient RTS guidelines based on time from surgery, which do not allow for proper healing or resolution of post-operative impairments and elimination of risk factors associated with both primary and secondary ACL injuries.

CONCLUSIONS

RTS rates to pre-injury level of activity after ACLR are poor and the risk for graft injury or contralateral injury requiring an additional surgery is substantial. Resolving impairments while eliminating movement patterns associated with injury and allowing sufficient time for graft healing likely gives the athlete the best chance to RTS without further injury. Additional research is needed to identify objective imaging and functional testing criteria to improve clinical decision making for RTS after ACLR.

LEVEL OF EVIDENCE

Level 5.