Anterior knee translation measurements after ACL reconstruction are influenced by the type of laximeter used

Association of Patient-Surgeon and Patient-Physical Therapist Relationships With Return to Sports After ACL Reconstruction: The Untested Dimension in Outcome Assessments

Background

The Quality of Patient-Surgeon Relationship (QPASREL) is an 11-item questionnaire developed and validated to assess the relationship between practitioners and patients on recovery and return to work after surgery.

Purpose

To evaluate the association of patient-surgeon relationship (PSR) and patient-physical therapist relationship (PPR), as measured by QPASREL, with a patient's return to sports (RTS) after anterior cruciate ligament reconstruction (ACLR).

Study Design

Case-control study; Level of evidence, 3.

Methods

This study targeted patients who underwent primary ACLR at a specialized sports surgery referral center between January and May 2021. Patients who had revision surgery, multiligamentous knee injury, and sedentary status were excluded from the study. Patients were grouped based on ability to RTS at the preinjury level 1 year postoperatively (RTS group and no-RTS group). The primary outcome was rate of RTS at 1 year postoperatively, and the primary dependent variables were the quality of PSR and PPR as measured by QPASREL scores at 6-month intervals. Secondary outcomes were the correlation and discriminative capacity of the QPASREL compared with the Anterior Cruciate Ligament-Return to Sport After Injury (ACL-RSI) scores (collected at 6-month intervals).

Results

The study included 243 patients. Patients in the RTS group exhibited a higher mean PPR QPASREL score (36.6 ± 5.1) compared with no-RTS patients (34.8 ± 5.2; P = .01) as well as a higher mean PSR score (35.7 ± 5.1) compared with no-RTS patients (33.8 ± 5.9; P = .01). Multivariate analysis showed that every 5-point increase in the QPASREL scores for PPR and PSR resulted in a 39% (odds ratio [OR] = 1.39; P = 0.014) and 35% (OR = 1.35, P = 0.021) increased odds of RTS, respectively. A weak yet positive correlation was found between QPASREL and ACL-RSI. The predictive capacity of the QPASREL (area under the curve [AUC] = 0.60 for PPR and 0.61 for PSR), although significant, was less powerful compared with that of the ACL-RSI (AUC = 0.73).

Conclusion

The quality of the PPR and PSR, as measured by QPASREL scores, demonstrated a significant association with RTS rates at 1 year after ACLR. A weak yet positive correlation was found between QPASREL and ACL-RSI.

DYNEELAX Robotic Arthrometer Reliability and Feasibility on Healthy and Anterior Cruciate Ligament Injured/Reconstructed Persons

Background

Anterior cruciate ligament (ACL) injuries are commonly assessed using clinical examination and magnetic resonance imaging, but these methods have limitations in reproducibility and quantification. Instrumented laxity measurements using devices, like the DYNEELAX®, offer an alternative approach. However, to date, there is no human data on the DYNEELAX® and the reliability of these devices remains a subject of debate, and there is no consensus on appropriate knee tightening levels for testing. We hypothesized that the DYNEELAX®, with standardized knee tightening, would provide reliable measurements of knee laxity in adult volunteers.

Methods

This prospective cohort study involved 48 pain-free adult volunteers. Laxity measurements were taken using a robotic-type motorized instrument (DYNEELAX®) on two separate occasions, at least 1 h and no more than 8 h apart, with knee tightening forces of 90 N ± 5 N. Metrics of anterior tibial translation and internal/external tibial axial rotations were recorded.

Results

The device displayed excellent intrarater reliability for all the metrics, with intraclass correlation coefficients ranging from 0.91 to 0.96. Anterior translation exhibited the highest reliability (intraclass correlation coefficient = 0.96), with a minimum detectable change of 0.83 mm.

Conclusions

DYNEELAX® is reliable in measuring knee laxity in adult volunteers when using standardized stabilizing knee tightening forces of 90 ± 5 N. The most sensitive measurement parameters (in terms of minimum detectable change as a proportion of the observed range) were anterior translation (in mm) at 150 N and secondary compliance.

Customized-individually-made origin® implants in total knee arthroplasty allow a reliable solution for accurate reproduction of planned implant positioning

PURPOSE

To evaluate the accuracy and reproducibility of a patient-specific, customized individually made (CIM) total knee replacement (TKR) using the ORIGIN® prosthesis.

METHODS

This was a prospective study conducted at a University Hospital from January 15, 2019, to April 30, 2021. The study included patients planned for an ORIGIN® CIM TKR procedure. Exclusion criteria included revision surgery, severe deformity, stiffness, or laxity. Evaluations were carried out using computed tomography scans performed 8 weeks preoperatively and 6 weeks postoperatively. The primary outcome measurements were the preoperative, planned, and postoperative CT scan alignment measurements including the Hip-Knee-Ankle (HKA) angle, mechanical Medial Distal Femoral articular surface Angle (mMDFA, distal alpha angle), Posterior Distal femoral articular surface angle (PDFA, posterior alpha angle), mechanical Medial Proximal Tibial articular surface Angle (mMPTA, beta angle) and posterior proximal tibial angle (PPTA). Secondary outcomes included the accuracy of implant positioning with percentage of outliers at 2° and 3° RESULTS: The study encompassed 51 knees from 50 patients with mean age of 68.1 (SD = 8.89). The overall HKA angle deviated by -0.93° [95% CI: -1.45; -0.43], and the PDFA angle by -0.61° [95% CI: -1.07; -0.15], while the mMPTA exceeded planned values by 1.00° [95% CI: 0.57; 1.43]. The 3° outliers rate ranged from 3.9% for the mMPTA to 7.8% for the HKA alignment, with no outliers in mMDFA and PPTA. Similarly, the 2° outliers rate ranged from 15.7% for both the PDFA angle and mMPTA to 19.6% for the HKA alignment. The Bland-Altman plots further emphasized the precision of planned and post-operative angles across all measurements.

CONCLUSION

The CIM TKR showed high accuracy and reproducibility, closely matching preoperative planning. The weakest accuracy at 3°-outliers is in the reproduction of the HKA alignment at 92.2% (range for all angle: 92.2-100%). Similarly, the weakest accuracy at 2°-outliers is in the reproduction of the HKA alignment at 80.4% (range for all angles: 80.4-92.2%).

Evaluation of Muscle Strength and Graft Laxity With Early Open Kinetic Chain Exercise After ACL Reconstruction: A Cohort Study

Background

Open kinetic chain (OKC) exercise is an effective method to improve muscle function during rehabilitation after anterior cruciate ligament reconstruction (ACLR); however, there is controversy about its use in the early phase of rehabilitation.

Purpose

To determine (1) whether the use of OKC and closed kinetic chain (CKC) exercises improves quadriceps and hamstring strength in the early phase of rehabilitation after ACLR and (2) whether the early use of OKC exercise affects graft laxity at 3 and 6 months postoperatively in patients with a hamstring tendon graft.

Study Design

Cohort study; Level of evidence, 3.

Methods

This study included an intervention group that underwent OKC + CKC exercises (n = 51) and a control group that underwent CKC exercise only (n = 52). In the intervention group, OKC exercise for the quadriceps and hamstring was started at 4 weeks after ACLR. At 3 and 6 months postoperatively, isokinetic testing was performed to calculate the limb symmetry index (LSI) and the peak torque to body weight ratio (PT/BW) for the quadriceps and hamstring. Anterior knee laxity was measured by an arthrometer.

Results

At 3 and 6 months postoperatively, quadriceps strength was higher in the intervention group than in the control group for the LSI (3 months: 76.14% ± 0.22% vs 46.91% ± 0.21%, respectively; 6 months: 91.05% ± 0.18% vs 61.80% ± 0.26%, respectively; P < .001 for both) and PT/BW (3 months: 1.81 ± 0.75 vs 0.85 ± 0.50 N·m/kg, respectively; 6 months: 2.40 ± 0.73 vs 1.39 ± 0.70 N·m/kg, respectively; P < .001 for both). There were similar findings regarding hamstring strength for the LSI (3 months: 86.13% ± 0.22% vs 64.26% ± 0.26%, respectively; 6 months: 91.90% ± 0.17% vs 82.42% ± 0.24%, respectively; P < .001 at three months, P = .024 at 6 months) and PT/BW (3 months: 1.09 ± 0.36 vs 0.67 ± 0.39 N·m/kg, respectively; 6 months: 1.42 ± 0.41 vs 1.07 ± 0.39 N·m/kg, respectively; P < .001 for both). No significant difference in laxity was observed between the intervention and control groups at 3 or 6 months.

Conclusion

Early use of OKC exercise for both the quadriceps and the hamstring, in addition to conventional CKC exercise, resulted in better correction of quadriceps and hamstring strength deficits without increasing graft laxity.

GNRB® laximeter with magnetic resonance imaging in clinical practice for complete and partial anterior cruciate ligament tears detection: A prospective diagnostic study with arthroscopic validation on 214 patients

BACKGROUND

Accurate diagnosis of anterior cruciate ligament (ACL) injury is not always obtained with magnetic resonance imaging (MRI). Other tools, such as the GNRB® arthrometer, help to accurately identify the type of ACL tear. The aim of this study was to show that the GNRB® could be a relevant complementary solution to MRI in ACL injuries detection.

METHODS

A prospective study performed between 2016 and 2020 included 214 patients who had undergone knee surgery. The study compared sensitivity/specificity pairs of MRI and the GNRB® at 134 N to detect healthy ACL, partial and complete ACL tears. Arthroscopies were the 'gold standard'. Forty-six patients had a healthy ACL with associated knee lesions, 168 patients had ACL tears where 107 were complete tears and 61 were partial tears.

RESULTS

For healthy ACL, MRI scored 100% for sensitivity (SE) and 95% for specificity (SP), and the GNRB® scored SE 95.65% and SP 97.5% at 134 N. For complete ACL tears, MRI scored 80.81% for sensitivity (SE) and 64.49% for specificity (SP), and the GNRB® scored SE 77.78% and SP 85.98% at 134 N. For partial tears, MRI scored SE 29.51% and SP 88.97%, and the GNRB® scored SE 73.77% and SP 85.52% at 134 N.

CONCLUSION

GNRB® sensitivity and specificity were equivalent to those of MRI for healthy ACL and complete ACL tear detection. However, MRI had some difficulty in detecting partial ACL tears compared with the GNRB® which showed better sensitivity.

Ecological and Specific Evidence-Based Safe Return To Play After Anterior Cruciate Ligament Reconstruction In Soccer Players: A New International Paradigm

Existing return to play (RTP) assessments have not demonstrated the ability to decrease risk of subsequent anterior cruciate ligament (ACL) injury after reconstruction (ACLR). RTP criteria are standardized and do not simulate the physical and cognitive activity required by the practice of sport. Most RTP criteria do not include an ecological approach. There are scientific algorithms as the "5 factor maximum model" that can identify risk profiles and help reduce the risk of a second anterior cruciate ligament injury. Nevertheless, these algorithms remain too standardized and do not include the situations experienced in games by soccer players. This is why it is important to integrate ecological situations specific to the environment of soccer players in order to evaluate players under conditions closest to their sporting activity, especially with high cognitive load. One should identify high risk players under two conditions: Clinical analyses commonly include assessments such as isokinetic testing, functional tests (hop tests, vertical force-velocity, profile), running, clinical assessments (range of motion and graft laxity), proprioception and balance (Star Excursion Balance Test modified, Y-Balance, stabilometry) and psychological parameters (kinesophobia, quality of life and fear of re-injury). Field testing usually includes game simulation, evaluation under dual-task conditions, fatigue and workload analysis, deceleration, timed-agility-test and horizontal force-velocity profiles. Although it seems important to evaluate strength, psychological variables and aerobic and anaerobic capacities, evaluation of neuromotor control in standard and ecological situations may be helpful for reducing the risk of injury after ACLR. This proposal for RTP testing after ACLR is supported by the scientific literature and attempts to approximate the physical and cognitive loads during a soccer match. Future scientific investigation will be required to demonstrate the validity of this approach.

Level of Evidence

5.

Magnetic Resonance Imaging Assessment of Hamstring Graft Healing and Integration 1 and Minimum 2 Years after ACL Reconstruction

BACKGROUND

An increase has been seen in the number of studies of anterior cruciate ligament reconstruction (ACLR) that use magnetic resonance imaging (MRI) as an outcome measure and proxy for healing and integration of the reconstruction graft. Despite this, the MRI appearance of a steady-state graft and how long it takes to achieve such an appearance have not yet been established.

PURPOSE

To establish whether a hamstring tendon autograft for ACLR changes in appearance on MRI scans between 1 and 2 years and whether this change affects a patient's ability to return to sports.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients with hamstring tendon autograft ACLR underwent MRI and clinical outcome measures at 1 year and at a final follow-up of at least 2 years. MRI graft signal was measured at multiple regions of interest using oblique reconstructions both parallel and perpendicular to the graft, with lower signal indicative of better healing and expressed as the signal intensity ratio (SIR). Changes in tunnel aperture areas were also measured. Clinical outcomes were side-to-side anterior laxity and patient-reported outcome measures (PROMs).

RESULTS

A total of 42 patients were included. At 1 year, the mean SIR for the graft was 2.7 ± 1.2. Graft SIR of the femoral aperture was significantly higher than that of the tibial aperture (3.4 ± 1.3 vs 2.6 ± 1.8, respectively; P = .022). Overall, no significant change was seen on MRI scans after 2 years; a proximal graft SIR of 1.9 provided a sensitivity of 96% to remain unchanged. However, in the 6 patients with the highest proximal graft SIR (>4) at 1 year, a significant reduction in signal was seen at final follow-up (P = .026), alongside an improvement in sporting level. A significant reduction in aperture area was also seen between 1 and 2 years (tibial, -6.3 mm², P < .001; femoral, -13.3 mm², P < .001), which was more marked in the group with proximal graft SIR >4 at 1 year and correlated with a reduction in graft signal. The patients had a high sporting level; the median Tegner activity score was 6 (range, 5-10), and a third of patients scored either 9 or 10. Overall, PROMs and knee laxity were not associated with MRI appearance.

CONCLUSION

In the majority of patients, graft SIR on MRI did not change significantly after 1 year, and a proximal graft SIR <2 was a sensitive indicator for a stable graft signal, implying healing. Monitoring is proposed for patients who have a high signal at 1 year (proximal graft SIR >4), because a significant reduction in signal was seen in the second year, indicative of ongoing healing, alongside an improvement in sporting level. A reduction in tunnel aperture area correlated with a reduction in graft SIR, suggesting this could also be a useful measure of graft integration.

Influence of residual anterior laxity on functional outcomes after anterior cruciate ligament reconstruction

INTRODUCTION

Residual laxity can persist after anterior cruciate ligament (ACL) reconstruction. This increased anterior translation can be measured with a knee arthrometer. Nevertheless, the measurement parameters and functional impact of this residual laxity are not well understood. The aims of this study were to (1) evaluate the effect of applying loads of 134N, 200N and 250N on the measured residual laxity after ACL reconstruction and (2) evaluate the prognostic ability of the various measurement parameters on the functional outcomes.

HYPOTHESIS

After ACL reconstruction, the functional outcomes will be correlated to the postoperative residual laxity.

METHODS

We did a prospective study of 61 recreational athletes who underwent surgical reconstruction of their ACL with the Kenneth-Jones technique between 2016 and 2019. The mean age of these patients was 27±7 years, and most were men (75%). The side-to-side difference in laxity was measured pre- and postoperatively using the GNRB® arthrometer at three load levels: 134N, 200N and 250N. The functional outcomes were determined based on the return to sports and the KOOS, IKDC and ARPEGE scores. The mean follow-up was 30±10 months.

RESULTS

Half the patients had returned to sport at their pre-injury levels, while 25% had returned to a lower level and 25% had stopped doing any physical activity. At 134N, a 1-mm increase in side-to-side difference was associated with a 2-fold higher risk of not returning to sports (OR 2; 95% CI 1.22-3.23; p<0.01). At 200N, a 1-mm increase in side-to-side difference was associated with a 50% higher probability of having a poor/fair ARPEGE score (OR 1.5; 95% CI 1.05-2.02; p=0.02). At 200N, a 4-mm side-to-side difference was the prognostic threshold for failure to return to sports with a positive predictive value of 86% and specificity of 98%.

CONCLUSIONS

This case series found a strong correlation between residual laxity and the functional outcomes after ACL reconstruction. A threshold of 4mm residual laxity evaluated on the GNRB® at 200N was predictive of adverse outcomes and failure to return to sports in our population of recreational athletes.

LEVEL OF EVIDENCE

IV, retrospective study.

Reliability of a Novel Automatic Knee Arthrometer for Measuring Knee Laxity After Anterior Cruciate Ligament Ruptures

Background:

The accuracy of existing devices for measuring knee laxity is adversely affected by examiner reliability.

Purpose:

To compare the accuracy of a novel automatic knee arthrometer (AKA) to that of the KT-2000 arthrometer for measuring knee laxity after anterior cruciate ligament (ACL) ruptures.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

We measured anterior displacement and the anterior displacement difference (ADD) at 134 N of anterior force in 221 healthy volunteers and 200 patients with ACL ruptures. All trials were performed by the same 2 examiners. We first analyzed the effects of examiner, side assessed, and device type using the intraclass correlation coefficient (ICC), t test, and F test. We then used the receiver operating characteristic curve to compare the diagnostic value of the measurements between devices.

Results:

In repeated measurements for a single healthy volunteer, there were no differences in the variance of the measurements between sides according to the AKA (standard deviation of right vs left knee for examiner A: 0.43 vs 0.58 mm, respectively [P = .39]; for examiner B: 0.49 vs 0.77 mm, respectively [P = .81]), while the KT-2000 measurements showed differences (standard deviation of right vs left knee for examiner A: 1.47 vs 0.80 mm, respectively [P = .02]; for examiner B: 1.78 vs 0.91 mm, respectively [P = .01]). The ADD assessed by the AKA was not significantly different between examiners A and B (0.50 vs 0.75 mm, respectively; P = .27; ICC = 0.83), but the KT-2000 showed a difference (1.07 vs 2.01 mm, respectively; P = .01; ICC = 0.55). The ADD of 20 healthy volunteers assessed by the AKA was less than that by the KT-2000 (0.98 vs 1.41 mm, respectively; P = .04). When comparing the diagnostic value of the 2 devices in the sample of 200 patients with ACL ruptures and 200 healthy controls, the area under the receiver operating characteristic curve for the AKA was larger than that for the KT-2000 (0.93 vs 0.87, respectively; P ≤ .01), and the threshold values were 1.75 and 2.73 mm, respectively.

Conclusion:

The AKA can be used to determine the degree of knee laxity in ACL injuries and to provide indications for treatment.

Female gender and medial meniscal lesions are associated with increased pain and symptoms following anterior cruciate ligament reconstruction in patients aged over 50 years

PURPOSE

Several studies report satisfactory clinical outcomes following ACLR in older patients, but none evaluated the effects of meniscal and cartilage lesions. The aim was to evaluate the influence of meniscal and cartilage lesions on outcomes of ACLR in patients aged over 50 years.

METHODS

The authors prospectively collected records of 228 patients that underwent primary ACLR, including demographics, time from injury to surgery, whether injuries were work related, and sports level (competitive, recreational, or none). At a minimum follow-up of 6 months, knee injury and osteoarthritis outcome scores (KOOS), International Knee Documentation Committee (IKDC) score and Tegner activity level were recorded, and differential laxity was measured as the side-to-side difference in anterior tibial translation (ATT) using instrumented laximetry devices. Regression analyses were performed to determine associations between outcomes and meniscal and cartilage lesions as well as nine independent variables.

RESULTS

A total of 228 patients aged 54.8 ± 4.3 years at index ACLR were assessed at a follow-up of 14.3 ± 3.8 months. KOOS subcomponents were 85 ± 13 for symptoms, 91 ± 10 for pain, 75 ± 18 for daily activities, 76 ± 18 for sport, and 88 ± 12 for quality of life (QoL). The IKDC score was A for 84 (37%) knees, B for 96 (42%) knees, C for 29 (13%) knees, and D for 8 (4%) knees. Tegner scores showed a decrease (median 0, range -4 to 4) and differential laxity also decreased (median - 4, range - 23.5 to 6.0). KOOS symptoms worsened with higher BMI (p = 0.038), for women (p = 0.007) and for knees that had medial meniscectomy (p = 0.029). KOOS pain worsened with higher BMI (p ≤ 0.001), for women (p = 0.002) and for knees with untreated (p = 0.047) or sutured (p = 0.041) medial meniscal lesions. Differential laxity increased with follow-up (p = 0.024) and in knees with lateral cartilage lesions (p = 0.031).

CONCLUSION

In primary ACLR for patients aged over 50 years, female gender and medial meniscal lesions significantly compromised KOOS symptoms and pain, while lateral cartilage lesions significantly increased differential laxity. Compared to knees with an intact medial meniscus, those with sutured or untreated medial meniscal lesions had worse pain, while those in which the medial meniscus was resected had worse symptoms. These findings are clinically relevant as they could help surgeons with patient selection and adjusting expectations according to their functional demands.

LEVEL OF EVIDENCE

III.

Two-year postoperative MRI appearances of anterior cruciate ligament hamstrings autografts are not correlated with functional outcomes, anterior laxity, or patient age

Aims

MRI has been suggested as an objective method of assessing anterior crucate ligament (ACL) graft “ligamentization” after reconstruction. It has been proposed that the MRI appearances could be used as an indicator of graft maturity and used as part of a return-to-sport assessment. The aim of this study was to evaluate the correlation between MRI graft signal and postoperative functional scores, anterior knee laxity, and patient age at operation.

Methods

A consecutive cohort of 149 patients who had undergone semitendinosus autograft ACL reconstruction, using femoral and tibial adjustable loop fixations, were evaluated retrospectively postoperatively at two years. All underwent MRI analysis of the ACL graft, performed using signal-to-noise quotient (SNQ) and the Howell score. Functional outcome scores (Lysholm, Tegner, International Knee Documentation Committee (IKDC) subjective, and IKDC objective) were obtained and all patients underwent instrumented side-to-side anterior laxity differential laxity testing.

Results

Two-year postoperative mean outcome scores were: Tegner 6.5 (2 to 10); Lysholm 89.8 (SD 10.4; 52 to 100); and IKDC subjective 86.8 (SD 11.8; 51 to 100). The objective IKDC score was 86% A (128 patients), 13% B (19 patients), and 1% C (two patients). Mean side-to-side anterior laxity difference (134 N force) was 0.6 mm (SD 1.8; -4.1 to 5.6). Mean graft SNQ was 2.0 (SD 3.5; -14 to 17). Graft Howell scores were I (61%, 91 patients), II (25%, 37 patients), III (13%, 19 patients), and IV (1%, two patients). There was no correlation between either Howell score or SNQ with instrumented anterior or Lysholm, Tegner, and IKDC scores, nor was any correlation found between patient age and ACL graft SNQ or Howell score.

Conclusion

The two-year postoperative MRI appearances of four-strand, semitendinosus ACL autografts (as measured by SNQ and Howell score) do not appear to have a relationship with postoperative functional scores, instrumented anterior laxity, or patient age at surgery. Other tools for analysis of graft maturity should be developed.

Cite this article: Bone Jt Open 2021;2(8):569–575.