Analysis of the influence of anaesthesia on the clinical and quantitative assessment of the pivot shift: a multicenter international study

Isolated meniscus allograft transplantation with soft-tissue technique effectively reduces knee laxity in the presence of previous meniscectomy: In-vivo navigation of 18 consecutive cases

OBJECTIVES

Although meniscal allograft transplantation (MAT) is a well-established procedure with satisfactory clinical results, limited in vivo kinematic information exists on the effect of medial and lateral MAT performed in the clinical setting. The purpose of the present study was to evaluate the biomechanical effect of arthroscopic isolated medial and lateral MAT with a soft-tissue fixation on pre- and post-operative knee laxity using a surgical navigation system.

METHODS

18 consecutive patients undergoing MAT (8 medial, 10 lateral) were enrolled. A surgical navigation system was used to quantify the anterior-posterior displacement at 30 and 90 degrees of knee flexion (AP30 and AP90), the varus-valgus rotation at 0 and 30 degrees of knee flexion (VV0 and VV30) and the dynamic laxity on the pivot-shift test (PS), which was determined through the anterior displacement of the lateral tibial compartment (APlat) and posterior acceleration of the lateral tibial compartment during tibial reduction (ACC). Data from laxity before and after MAT were compared through paired t-test (p ​< ​0.05).

RESULTS

After medial MAT, there was a significant decrease in tibial translation of 3.1 ​mm (31%; p ​= ​0.001) for AP30 and 2.3 ​mm (27%; p ​= ​0.020) for AP90, a significant difference of 2.5° (50%; p ​= ​0.002) for VV0 and 1.7° (27%; p ​= ​0.012) for VV30. However, medial MAT did not determine any reduction in the PS kinematic data. Lateral MAT determined a significant decrease in the tibial translation of 2.5 ​mm (38%; p ​< ​0.001) for AP30 and 1.9 ​mm (34%; p ​= ​0.004) for AP90 as well as a significant difference of 3.4° (59%; p ​< ​0.001) for VV0 and of 1.7° (23%; p ​= ​0.011) for VV30. There was also a significant reduction of the PS of 4.4 ​mm (22%; p ​= ​0.028) for APlat and 384.8 ​mm/s2 (51%; p ​= ​0.005) for ACC.

CONCLUSION

MAT with soft-tissue fixation results in a significant laxity reduction in an in-vivo setting. Medial MAT improved knee kinematics by determining a significant reduction with particular emphasis on AP translation and VV manoeuvre. Conversely, Lateral MAT determined a massive reduction of the PS and a mild decrease of the AP translation and VV manoeuvre.

STUDY DESIGN

Controlled laboratory study.

Bilateral Knee Dislocations in an Active Duty Service Member: A Case Report

This case highlights a staged operative approach for a patient who sustained bilateral knee dislocations and subsequent staged operative treatment and rehabilitation. This patient underwent bilateral multiligamentous knee reconstructions and left-sided peroneal nerve allografting because of complete peroneal nerve palsy. The initial treatment was bilateral medial collateral ligament reconstructions, posterolateral corner reconstructions, and capsular repairs with left leg peroneal nerve allografting and repair of avulsed biceps femoris tendon. The patient underwent physical therapy following the first stage procedure until he regained appropriate motion and soft tissue healing occurred. Subsequently, combined anterior cruciate and posterior cruciate ligament reconstructions were performed in a staged fashion to allow one leg to fully bear weight for rehabilitation purposes. With the help of a multidisciplinary surgical and rehabilitation team, the patient has regained the stability of his knees and achieved acceptable functional outcomes. A staged systematic approach to multiligamentous bilateral knee reconstruction can provide optimal pain management, obtain initial joint stability, minimize complications, and achieve acceptable functional outcomes. Surgical techniques to first restore medial and lateral structures can be utilized to provide initial valgus and varus stability while allowing for knee mobilization and, eventually, in-line ambulation, before staged anterior and posterior cruciate ligament reconstructions. This case demonstrates a multistaged approach to bilateral knee dislocations with favorable outcomes in a 23-year-old active duty patient.

Posterior tibial plateau impaction fractures are not associated with increased knee instability: a quantitative pivot shift analysis

PURPOSE

This study aimed to evaluate posterolateral tibial plateau impaction fractures and how they contribute to rotatory knee laxity using quantitative pivot shift analysis. It was hypothesised that neither the presence of nor the degree of involvement of the plateau would affect rotatory knee laxity in the ACL-deficient knee.

METHODS

A retrospective review of prospectively collected data on 284 patients with complete anterior cruciate ligament (ACL) injuries was conducted. Posterolateral tibial plateau impaction fractures were identified on preoperative MRI. The patients were divided into two cohorts: "fractures" or "no fractures". The cohort with fractures was further categorised based on fracture morphology: "extra-articular", "articular-impaction", or "displaced-articular fragment". All data were collected during examination under anaesthesia performed immediately prior to ACL reconstruction. This included a standard pivot shift test graded by the examiner and quantitative data including anterior tibial translation (mm) via Rolimeter, quantitative pivot shift (QPS) examination (mm) via PIVOT tablet technology, and acceleration (m/sec²) during the pivot shift test via accelerometer. Quantitative examinations were compared with the contralateral knee.

RESULTS

There were 112 patients with posterolateral tibial plateau impaction fractures (112/284, 39%). Of these, 71/112 (63%) were "extra-articular", 28/112 (25%) "articular-impaction", and 13/112 (12%) "displaced-articular". Regarding the two groups with or without fractures, there was no difference in subjective pivot shift (2 ± 0 vs 2 ± 0, respectively,  n.s.), QPS (2.4 ± 1.6 mm vs 2.7 ± 2.2 mm, respectively, n.s.), anterior tibial translation measurements (6 ± 3 mm vs 5 ± 3 mm, respectively, n.s.), or acceleration of the knee during the pivot (1.7 ± 2.3 m/s² vs 1.8 ± 3.1 m/s², respectively, n.s.). When the fractures were further subdivided, subgroup analysis revealed no significant differences noted in any of the measured examinations between the fracture subtypes.

CONCLUSION

This study showed that the posterolateral tibial plateau impaction fractures are commonly encountered in the setting of ACL tears; however, contrary to previous reports, they do not significantly increase rotatory knee laxity. This suggests that this type of concomitant injury may not need to be addressed at the time of ACL reconstruction.

LEVEL OF EVIDENCE

Level III.

The presence of high-grade pivot shift test preoperatively is associated with inferior functional outcomes

BACKGROUND

The effect of high-grade preoperative pivot shift test on outcomes of anterior cruciate ligament (ACL) reconstruction surgery is not very well established. The present study was conducted to study the factors associated with high-grade pivot shift test and effect of high-grade preoperative pivot shift test on functional outcomes after ACL reconstruction surgery.

METHODS

Three hundred and sixty-two patients who underwent primary ACL reconstruction surgery were enrolled in the study. The pivot shift test was performed preoperatively under anesthesia in all patients. Side of the meniscal tear, if present at the time of ACL reconstruction, was documented. Patients were divided into two groups depending upon the grade of pivot shift test: group H, high-grade pivot shift (n = 84/362; 23%); and group L, low-grade pivot shift (n = 278/362; 77%). Patients were further divided into two groups depending upon the duration of injury: acute (<6 months) and chronic (>6 months). The functional assessment was done using Lysholm score and Tegner activity scale.

RESULTS

The presence of lateral meniscus tear (27/84 vs. 53/278) or both menisci tear (29/84 vs. 60/278) was associated with high-grade pivot shift (p < 0.05). Chronic ACL tears were also observed to be associated with high-grade pivot shift (p = 0.03). The mean Lysholm score in group H and group L patients was 93.8 ± 5.1 and 95.2 ± 5.3, respectively (p = 0.04). The mean post-op Tegner activity scale in group H was 6.8 and in group L was 7.3 (p = 0.0001). Also, 181/253 (71.5%) patients returned to same or higher level of sports activity in group L as compared to 33/72 (46%) patients in group H. The incidence of graft failure in groups H and L was 6.5% (5/77) and 1.6% (4/257; p = 0.03), respectively.

CONCLUSIONS

The high-grade pivot shift is associated with chronic ACL tear (>6 months) and concomitant lateral meniscus tear. The presence of high-grade pivot shift preoperatively is associated with inferior clinical outcomes and lower rate of return to sports.

LEVEL OF EVIDENCE

Level IV, case-control study.

S, J.S. ST, Nair RR. Comparison of Fixed- and Variable-Loop Button Fixation in Arthroscopic Anterior Cruciate Ligament Reconstruction

Introduction

With the advent of fixed- and variable-loop suspensory fixation devices for arthroscopic anterior cruciate ligament (ACL) reconstruction, a maximum number of grafts can be placed within the femoral tunnel. Although several biomechanical studies have been conducted comparing these two devices, only a few comparative clinical studies are available. This study was conducted to compare the functional outcomes of arthroscopic ACL reconstruction using fixed-loop devices with those of variable-loop devices by determining their effect on graft laxity clinical assessment and patient-reported outcome scores.

Methodology

Out of 32 patients (27 males and five females) who underwent primary ACL reconstruction using tripled hamstring autograft, fixed- and variable-loop devices were used for 13 and 19 patients, respectively. Thirteen patients in each group were evaluated over a period of one year using the Lysholm knee score. Six patients in the variable-loop group had only six months of follow-up. Anterior drawer and Lachman tests were performed at six-month and one-year follow-ups, respectively.

Results

The mean ages of patients in the fixed- and variable-loop groups were 34.5\begin{document}\pm\end{document}11 and 34.1\begin{document}\pm\end{document}9.1 years, respectively. The Lysholm knee score at six weeks was fair in 7.7% of the patients in the fixed-loop group when compared to 52.6% of those in the variable-loop group (p<0.05). All the other parameters were comparable between the two groups. One patient in each group had ligament laxity at six-month and one-year follow-up, respectively.

Conclusion

This study showed no statistically significant difference in graft laxity or functional outcomes of arthroscopic ACL reconstruction with fixed- and variable-loop devices, except for a better patient-reported outcome score in the variable-loop group at six weeks of follow-up. Hence, there is a need for more comparative studies in this direction.

[Anterolateral stabilization using the modified ellison technique-Treatment of anterolateral instability and reduction of ACL re-rupture risk]

OBJECTIVE

The goal of the modified Ellison operation as a supplement to a conventional anterior cruciate ligament (ACL) reconstruction is to decrease anterolateral rotational instability of a knee joint after ACL rupture, to improve the stability and prevent ACL re-rupture.

INDICATIONS

An ACL rupture with high risk of re-rupture (young age, high-performance sport, hyperlaxity, contralateral ACL rupture in history), increased subjective and objective anterolateral rotational instability of the knee after ACL rupture, ACL re-rupture.

CONTRAINDICATIONS

Gonarthrosis, additive instabilities (e.g. posterolateral, medial), non-anatomical ACL reconstruction with persistent instability, general contraindications to surgery (e.g. infections), chronic irritation of the knee joint.

SURGICAL TECHNIQUE

Supine position. Mark the typical landmarks. Incision from Gerdy's tubercle extending proximally along the iliotibial tract (ITT) to the lateral collateral ligament (approx. 5 cm). Incise the ITT in the line of its fibers about 10 mm anterior to its posterior border and continue the incision proximally to 5 mm proximal to the LCL. Make a parallel incision 10-12 mm anterior to the first incision. Use sharp subperiosteal dissection to elevate the strip of the ITT from Gerdy's tubercle. Secure the distal end of the ITT strip with a nonabsorbable suture (e.g. FiberWire No. 2, Arthrex, Naples, USA). Expose the LCL and pass the ITT strip deep to the LCL from proximal to distal and back to Gerdy's tubercle. Reattach the distal end of the strip of the ITT to its original position at Gerdy's tubercle with a bone anchor. The defect in the ITT can be closed with an absorbable suture (e.g. Vicryl, Ethicon, USA) in the proximal part. Layered closure.

POSTOPERATIVE MANAGEMENT

Knee brace for at least 6 weeks, movement limitation of 0‑0-90° for 6 weeks, 2 weeks 20 kg partial weight bearing.

RESULTS

A total of 36 patients (mean age 18.9 years) with a high risk of ACL re-rupture have been treated with ACL reconstruction and modified Ellison procedure. Follow-up over 2 years. Of the patients 35 returned to the previous sports level, 1 patient suffered a re-rupture, 2 patients had cyclops resection and 1 patient contralateral ACL rupture.

Augmentation of Anatomic Anterior Cruciate Ligament Reconstruction With Lateral Extra-articular Tenodesis Does Not Significantly Affect Rotatory Knee Laxity: A Time Zero, In Vivo Kinematic Analysis

BACKGROUND

The pivot-shift test is used to assess for rotatory knee laxity in the anterior cruciate ligament (ACL)-deficient knee and ACL-reconstructed knee; however, the pivot shift uses a subjective grading system that is limited by variability between examiners. Consequently, quantified pivot shift (QPS) test software (PIVOT iPad application) has been developed and validated to measure the magnitude of rotatory knee laxity during the positive pivot-shift test.

PURPOSE

To employ intraoperative QPS (iQPS) to assess for differences in residual rotatory knee laxity after ACL reconstruction (ACLR) versus ACLR augmented with lateral extra-articular tenodesis (ACLR + LET), and to employ iQPS to determine if ACLR and/or ACLR + LET result in overconstrained knee kinematics when compared with the contralateral knee.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

iQPS was performed in 20 patients by a single surgeon on both the operative and contralateral knees before ACLR. ACLR was augmented with a LET if the lateral compartment tibial translation measured during QPS was greater than or equal to double the amount of lateral tibial compartment translation measured for the contralateral knee. After each reconstruction (ACLR or ACLR + LET), iQPS measurements were performed. iQPS data were compared with the preoperative QPS measurements of the operative and contralateral knees. Postoperative iQPS data were compared with both the preoperative QPS measurements of the operative and contralateral knees with paired samples t tests. Categorical variables were compared using the Fisher exact test.

RESULTS

The mean age in the cohort was 17.3 years (range, 15-24 years). There were no significant differences between the groups in terms of the proportion of male patients (ACLR: 5 male, 5 female vs ACLR + LET: 4 male, 6 female) or age (ACLR: 17.7 ± 3.3 years; 95% CI, 15.4-24.0 vs ACLR + LET: 16.8 ± 2.8 years, 95% CI, 14.8-22.0; P = .999). There were no significant differences between the groups with respect to preoperative QPS performed during examination under anesthesia (ACLR: 4.7 ± 2.0 mm; 95% CI, 3.3-6.1 vs ACLR + LET: 3.6 ± 1.8 mm; 95% CI, 2.3-4.9; P = .2). Both ACLR and ACLR + LET resulted in significant decreases in rotatory knee laxity when compared with preoperative QPS measurements (ACLR: -3.4 ± 1.7 mm; 95% CI, -4.6 to -2.2; P < .001: ACLR + LET: -2.6 ± 1.9 mm; 95% CI, -3.9 to -1.3; P < .002). Moreover, when compared with isolated ACLR, ACLR + LET did not result in a significantly smaller magnitude of change in iQPS between the pre- and postoperative states (P = .3).

CONCLUSION

Both ACLR and ACLR + LET resulted in significant decreases in rotatory knee laxity. The augmentation of ACLR with LET did not change the constraint of the knee with respect to lateral compartment translation as measured during iQPS.

Objectifying the Pivot Shift Test

The pivot shift test is utilized for assessment of rotatory instability in the anterior cruciate ligament (ACL) deficient knee. There are multiple reports of the pivot shift maneuver, and there is a lack of consensus among clinicians as to a standardized maneuver. Measurement devices are a feasible option to evaluate rotatory knee instability, objectively or quantitatively. Traditionally, measurement systems have been invasive systems. More recently, electromagnetic system, inertial sensor, or imaging analysis systems, specifically with the utilization of a tablet computer, have emerged as noninvasive, and more importantly, validated options. It is important to recognize that anatomic structures other than the ACL contribute to rotatory knee stability. Addressing the tibial slope, anterolateral structures of the knee, specifically the iliotibial band, and menisci during ACL surgery may decrease residual pivot shift in an attempt to improve clinical outcomes and prevent reinjury. This review article describes the pivot shift maneuver, objective measurement tools, and clinical applications of the pivot shift test.

Quantitative assessment of the pivot shift test with smartphone accelerometer

PURPOSE

The pivot shift (PS) test is commonly used to diagnose and evaluate the dynamic instability of the knee joint in cases of anterior cruciate ligament (ACL) tear. There is a need of a reliable and inexpensive tool which is easily available to measure PS objectively in a clinical setting. The purpose of this study was to evaluate the use of a smartphone, which is readily available, to assess the PS phenomenon.

METHODS

Seventeen patients with unilateral ACL-injured knees, undergoing ACL reconstruction, were enrolled in the study. PS was initially graded according to the International Knee Documentation Committee classification by two observers. The PS test was then performed by them in normal and injured knees under anaesthesia using a smartphone attached to Gerdy's tubercle. Acceleration changes during the PS test were recorded using the smartphone accelerometer application. Intra-observer and inter-observer reliability of the test among the two observers were evaluated. Acceleration changes were compared between the injured and normal knees, and also between the clinical grades of PS. Diagnostic utility of the smartphone accelerometer was examined by a receiver operating characteristic curve analysis.

RESULTS

Intra-observer and inter-observer reliability were high for the smartphone accelerometer. The acceleration change was higher in the ACL-injured knees than in normal knees. The mean acceleration change was 2.54 m/s² (SD = 0.97) in ACL-injured knees and 0.73 m/s² (SD = 0.19) in normal knees (p < 0.001). The mean acceleration change of Grade 1 knees was 1.89 m/s² (SD = 0.57), and that of knees of Grade 2 and above were 2.99 m/s² (SD = 0.95) (p < 0.05). Sensitivity was 94% and specificity was 100% for the acceleration change required to detect ACL injury, i.e., 1.24 m/s².

CONCLUSIONS

The results show that a smartphone can be used to evaluate the PS quantitatively and reliably, in the diagnosis of ACL injury.

LEVEL OF EVIDENCE

II.

Patient-Reported and Quantitative Outcomes of Anatomic Anterior Cruciate Ligament Reconstruction With Hamstring Tendon Autografts

Background:

The pivot-shift test has become more consistent and reliable and is a meaningful outcome measurement after anterior cruciate ligament reconstruction (ACLR).

Purpose/Hypothesis:

The purpose of this investigation was to assess patient-reported outcomes (PROs) and the quantitative pivot shift (QPS) preoperatively, at time zero immediately after anatomic ACLR, and after 24 months as well as the relationship between PROs and the QPS. It was hypothesized that anatomic ACLR would restore rotatory stability measured by the pivot-shift test and that QPS measurements would be positively correlated with PROs.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

The ACL-injured and contralateral uninjured knees from 89 of 107 (83.2%) enrolled patients at 4 international centers were evaluated using a standardized pivot-shift test. Tibial acceleration was assessed with an inertial sensor, and lateral compartment translation was measured using an image analysis system preoperatively, at time zero immediately postoperatively, and at follow-up after 2 years. PROs were assessed at 12 and 24 months postoperatively with the International Knee Documentation Committee (IKDC) subjective knee form, Cincinnati Knee Rating System (CKRS), Marx activity rating scale, and activity of daily living score (ADLS).

Results:

The mean patient age at surgery was 27 years (range, 15-45 years). A positive pivot shift preoperatively (side-to-side difference in tibial acceleration, 2.6 ± 4.0 m/s²; side-to-side difference in anterior tibial translation, 2.0 ± 2.0 mm) was reduced at time zero postoperatively (side-to-side difference in tibial acceleration, –0.5 ± 1.3 m/s²; side-to-side difference in anterior tibial translation, –0.1 ± 1.0 mm). All PROs improved from preoperatively to final follow-up at 24 months: from 56.5 to 85.5 points for the IKDC (P = .0001), from 28.8 to 32.4 points for the CKRS (P = .04), from 11.2 to 7.9 points for the Marx (P < .0001), and from 75.7 to 91.6 points for the ADLS (P < .0001). Neither preoperative nor time zero postoperative rotatory laxity assessed by the pivot-shift test correlated with PROs at 24-month follow-up. A graft retear was observed in 4 patients (4.5%) within 2 years of follow-up.

Conclusion:

Anatomic ACLR resulted in significantly improved and acceptable PROs at 2-year follow-up and a low failure rate. Anatomic ACLR restored QPS measurements of anterior tibial translation and tibial acceleration to those of the contralateral knee immediately after surgery while still under anesthesia, but there was no correlation between the QPS preoperatively or at time zero after ACLR and PROs at 2-year follow-up.

Stress radiography at 30° of knee flexion is a reliable evaluation tool for high-grade rotatory laxity in complete ACL-injured knees

PURPOSE

To evaluate the diagnostic value of stress radiography and determine the cutoff values for high-grade anterolateral rotatory laxity in complete anterior cruciate ligament (ACL)-deficient knees at different positions.

METHODS

Forty-two patients with complete ACL rupture (group 1) and 37 normal subjects (group 2) were prospectively enrolled. The amount of anterior translation in the medial (MM) and lateral (LL) distance compartments and the difference between them (LL-MM distance) were measured using stress radiography at 30°, 45°, 60°, and 90° positions. The area under the receiver operating characteristic curve (AUC) was assessed for the presence of a high-grade (grade > 2) pivot shift.

RESULTS

The MM and LL distances in group 1 were significantly different at 30° and 45° positions (P < 0.05). The AUC of the MM (AUC, 0.903) and LL (AUC, 0.901) distances at the 30° position was significantly higher than that of the other positions (P = 0.000); however, the cutoff values were different to diagnose ACL injury (MM vs. LL, 3.1 mm vs. 5.4 mm). A 2.1-mm cutoff for the LL-MM distance showed 78.4% sensitivity and 90.3% specificity for detecting the presence of a high-grade pivot shift (AUC = 0.905, P = 0.000).

CONCLUSION

The cutoff values of stress radiography differed according to anatomical references and knee flexion positions. Stress radiography of a 2.1 mm difference in LL-MM distance at 30° of knee flexion can be a reliable method for high-grade rotatory laxity in complete ACL-injured knees.

LEVEL OF EVIDENCE

Level 1, diagnostic study.

[Research progress in anterolateral ligament of knee]

Objective

To review research progress in the anterolateral ligament (ALL) of knee, and provide a clinical reference for diagnosis and treatment of ALL injury.

Methods

The literature on the diagnosis and treatment of ALL injury was widely reviewed. The incidence, anatomy, biomechanics, injury mechanism, and treatment status of ALL were summarized.

Results

The ALL contributes to the effect of controlling the internal rotation and anterior translation of the tibia, which affects the axial migration of the knee. ALL injury can be diagnosed according to the signs and MRI examination. Currently, no consensus exists for the surgical indications of ALL injury, but most surgeons tend to perform ALL reconstruction in patients requiring anterior cruciate ligament (ACL) reconstruction or revision surgery with higher pivot-shift tests. At present, various techniques have been used for ALL reconstruction, and there is no optimal technique. In addition, the long-term effectiveness of ALL reconstruction is unclear due to the lack of high-quality studies and long-term postoperative follow-up.

Conclusion

The ALL contributes to maintaining knee stability, and the ALL reconstruction technique and its effectiveness still need further research.

Combined ACL and Anterolateral Reconstruction Is Not Associated With a Higher Risk of Adverse Outcomes: Preliminary Results From the SANTI Randomized Controlled Trial

Background

The widespread historical abandonment of lateral extra-articular procedures in anterior cruciate ligament (ACL) injuries occurred as a result of concerns about high rates of adverse events. Recently, the popularity of lateral extra-articular procedures has resurged, warranting an urgent evaluation of their safety profile.

Purpose/Hypothesis

The aim of this study was to perform an interim analysis of the ongoing SANTI randomized controlled trial to determine whether combined ACL and anterolateral ligament reconstruction (ACL + ALLR) is associated with an increased rate of adverse outcomes when compared with isolated ACL reconstruction (ACLR). The hypothesis was that there would be no significant difference between groups at a minimum follow-up of 1 year.

Study Design

Randomized controlled trial; Level of evidence, 1.

Methods

Recruitment commenced in November 2016. Patients scheduled for ACLR were randomized to either isolated ACLR (with bone-patellar tendon-bone [BPTB] autograft) or combined ACL + ALLR (with hamstring tendon autograft). All patients with a minimum follow-up of 1 year by March 2019 were included. The evaluated parameters included complications and reoperations, knee laxity parameters, range of motion, and scores on the Tegner, Lysholm, International Knee Documentation Committee (IKDC), and Knee injury and Osteoarthritis Outcome Score (KOOS) instruments.

Results

A total of 224 patients (112 in each group) with a mean ± SD follow-up of 12.3 ± 1.9 months (range, 12-19 months) formed the study population. A significantly higher rate of reoperation for cyclops syndrome was noted in the isolated ACLR group compared with the combined ACL + ALLR group (8.9% vs 0%, respectively; P = .0012). No significant differences were found in frequency of graft rupture (ACLR, 5.4%; ACL + ALLR, 0.9%; P = .1191), range of motion deficits, pain, or reoperation for meniscectomy between groups. No cases of postoperative infection, venous thromboembolism, or arthrofibrosis were seen. Subjective IKDC (81.2 vs 86.8; P = .0048), Lysholm (88 vs 92; P = .0131), and some components of the KOOS were significantly better in the combined ACL + ALLR group.

Conclusion

This study demonstrates no evidence of an increased risk of short-term adverse events after combined ACL + ALLR compared with isolated ACLR with BPTB graft.

Registration

NCT03740022 (ClinicalTrials.gov Identifier).

Triaxial accelerometer evaluation is correlated with IKDC grade of pivot shift

PURPOSE

The purpose of this study was to evaluate the correlation between tibial acceleration parameters measured by the KiRA device and the clinical grade of pivot shift. The secondary objective was to report the risk factors for pre-operative high-grade pivot shift.

METHODS

Two-hundred and ninety-five ACL deficient patients were examined under anesthesia. The pivot shift tests were performed twice by an expert surgeon. Clinical grading was performed using the International Knee Documentation Committee (IKDC) scale and tibial acceleration data was recorded using a triaxial accelerometer system (KiRA). The difference in the tibial acceleration range between injured and contralateral limbs was used in the analysis. Correlation coefficients were calculated using linear regression. Multivariate logistic regression was used to identify risk factors for high grade pivot shift.

RESULTS

The clinical grade of pivot shift and the side-to-side difference in delta tibial acceleration determined by KiRA were significantly correlated (r = 0.57; 95% CI 0.513-0.658, p < 0.0001). The only risk factor identified to have a significant association with high grade pivot shift was an antero-posterior side to side laxity difference > 6 mm (OR = 2.070; 95% CI (1.259-3.405), p = 0.0042).

CONCLUSION

Side-to-side difference in tibial acceleration range, as measured by KiRA, is correlated with the IKDC pivot shift grade in anaesthetized patients. Side-to-side A-P laxity difference greater than 6 mm is reported as a newly defined risk factor for high grade pivot shift in the ACL injured knee.

DIAGNOSTIC STUDY

Level II.

Knee hyperextension and a small lateral condyle are associated with greater quantified antero-lateral rotatory instability in the patients with a complete anterior cruciate ligament (ACL) rupture

PURPOSE

To identify factors associated with quantified rotatory stability (pivot-shift phenomenon) in the anterior cruciate ligament (ACL)-injured knee joint.

METHODS

A consecutive sample of 54 patients who were diagnosed with an ACL injury and admitted to our hospital to undergo ACL reconstruction were enrolled in this study. Antero-lateral rotatory laxity of the knee joint was quantified using a Kinematic Rapid Assessment device (KiRA; Orthokey LTD) under spinal block before initiating reconstruction of the ACL. Univariate and multivariate regressions were performed assuming relationships between patient characteristics (independent variables) and quantified antero-lateral rotatory stability (a dependent variable).

RESULTS

It was observed that a low BMI (t = - 1.659, n.s.), greater passive knee extension angle (t = 2.374, P = 0.023), and a narrower lateral femoral condyle width index (t = - 1.712, n.s.) could be candidates associated with the antero-lateral rotatory instability, using univariate analysis. Employing multivariate analysis controlling for these three variables, that the range of passive knee extension was found to be significantly associated with antero-lateral rotatory instability in the ACL-injured knee joint (t = 2.21, P = 0.035). Patients were then divided into two groups (pivot-shift negative versus positive groups) based on the KiRA-documented quantified pivot-shift test. Interestingly, 23.3% of patients were pivot-shift negative, even though their ACL was confirmed as a complete rupture by arthroscopic observations. The degree of passive knee extension was 2.3 ± 4.5 (mean ± SD) in the pivot-shift negative group, while it was 6.8 ± 6.6 in the pivot-shift positive group (n.s.). The lateral femoral condyle width index was 36.6 ± 2.0% in the pivot-shift negative group, and it was significantly wider than in the pivot-shift positive group (33.8 ± 2.6%, P = 0.0046). Finally, we estimated that the risk of positive pivot-shift depends on the degree of knee extension. The logistic regression analysis revealed that genu recurvatum significantly increased the odds ratio for positive pivot-shift (OR = 3.08, P = 0.047, 95% CI = 1.017-9.350).

CONCLUSIONS

This study revealed that greater antero-lateral rotatory instability in patients with a complete ACL rupture was associated with genu recurvatum and small lateral femoral condyle. These factors should be considered as predictors of a poor outcome from an ACL reconstruction due to a higher load on the ACL graft, and therefore, the attending physicians should modify the treatment strategies accordingly. This study indicates that joint hyperlaxity and bone morphology contribute to the rotational stability of the knee joint, in addition to the ACL and antero-lateral complex (ALC).

LEVEL OF EVIDENCE

IV.

Combined reconstruction of the anterolateral ligament in chronic ACL injuries leads to better clinical outcomes than isolated ACL reconstruction

PURPOSE

To evaluate the results of combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction in patients with chronic ACL injury. It was hypothesized that patients who underwent combined ACL and ALL reconstruction would exhibit less residual laxity and better clinical outcomes.

METHODS

Two groups of patients were evaluated and compared retrospectively. Both groups consisted only of patients with chronic (more than 12 months) ACL injuries. Patients in group 1 underwent anatomical intra-articular reconstruction of the ACL and patients in group 2 underwent anatomic intra-articular ACL reconstruction combined with ALL reconstruction. The presence of associated meniscal injury, the subjective International Knee Documentation Committee (IKDC) and Lysholm functional outcome scores in the postoperative period, KT-1000 evaluation, the presence of residual pivot shift and graft rupture rate were evaluated.

RESULTS

One hundred and one patients who underwent reconstruction of chronic ACL injuries were evaluated. The median follow-up was 26 (24-29) months for group 1 and 25 (24-28) months for group 2. There were no significant differences between groups regarding gender, age, duration of injury until reconstruction, follow-up time or presence of associated meniscal injuries in the preoperative period. Regarding functional outcome scores, patients in group 2 presented better results on both the IKDC (p = 0.0013) and the Lysholm (p < 0.0001) evaluations. In addition, patients in group 2 had better KT-1000 evaluation (p = 0.048) and a lower pivot shift rate at physical examination, presenting only 9.1% positivity versus 35.3% in the isolated ACL reconstruction (p = 0.011). Regarding re-ruptures, group 1 presented 5 (7.3%) cases, and group 2 presented no cases.

CONCLUSION

The combined ACL and ALL reconstruction in patients with chronic ACL injury is an effective and safety solution and leads to good functional outcomes with no increase in complication rate. The clinical relevance of this finding is the possibility to indicate this type of procedure when patients present with more than 12 months after injury for surgery.

LEVEL OF EVIDENCE

Level III.

[Anterolateral stabilization using the modified Lemaire technique for ACL deficiency]

OBJECTIVE

Treatment of persistent anterolateral knee instability.

INDICATIONS

Subjective/objective (rotational) instability of the knee after anatomic anterior cruciate ligament (ACL) reconstruction. ACL re-rupture including special demands (e.g., high-performance athletes, hyperlaxity) RELATIVE CONTRAINDICATIONS: Osteoarthritis, additional instability of the knee, which should be treated independently; non-anatomic ACL reconstruction with persisting instability should be treated first with anatomic ACL reconstruction.

ABSOLUTE CONTRAINDICATIONS

General contraindications for surgery (e. g. septic arthritis), acute irritation of the affected knee.

SURGICAL TECHNIQUE

Supine position. Incision along the proximal lateral femoral epicondyle. Marking of the needed width and length of the iliotibial band (ITB) graft. Passing the ITB graft underneath the lateral collateral ligament. Find and mark the isometric point for fixation next to the lateral femoral epicondyle. Fixation of the ITB graft. Layered wound closure.

POSTOPERATIVE MANAGEMENT

Knee brace for at least 6 weeks. Range of motion (RoM): from postoperative day 1: flexion-extension 90-0-0°; first 2 weeks after surgery: partial weight bearing (20 kg).

RESULTS

An anterolateral extra-articular reconstruction may reduce a persistent anterolateral rotatory instability as well as the re-rupture rate following ACL reconstruction with good patient-reported short-term outcomes. Based on current (biomechanical) data, anterolateral tenodesis seems to be superior to a reconstruction of the anterolateral ligament. If a tenodesis is performed, the graft should be fixed in an isometric position, with neutral rotation of the knee and low graft tension to avoid extraphysiologic load within the lateral compartment. Indications for such a procedure may include a high-grade pivot shift or revision ACL reconstruction as well as a persistent anterolateral rotatory instability following anatomic ACL reconstruction.

The diagnostic reliability of the quantitative pivot-shift evaluation using an electromagnetic measurement system for anterior cruciate ligament deficiency was superior to those of the accelerometer and iPad image analysis

PURPOSE

Several non-invasive devices have been developed to obtain quantitative assessment of the pivot-shift test in clinical setting using similar but diverse measurement parameters. However, the clinical usability of those measurements has yet to be closely investigated and compared. The purpose of this study was to compare the diagnostic accuracy of three non-invasive measurement devices for the pivot-shift test.

METHODS

Thirty patients with unilateral anterior cruciate ligament (ACL) injury were enrolled. The pivot-shift test was performed under general anaesthesia. Three devices, an accelerometer system (KiRA), an image analysis iPad application (iPad), and electromagnetic measurement system (EMS), were used simultaneously to provide two parameters, namely tibial acceleration monitored using KiRA and EMS, and tibial translation recorded using iPad and EMS. Side-to-side differences in each parameter and correlation between the measurements were tested, and a receiver-operating characteristic (ROC) curve analysis was conducted to compare their measurement accuracy.

RESULTS

Significant side-to-side differences were successfully detected using any of the measurements (all p < 0.01). KiRA demonstrated moderate correlation with the EMS for tibial acceleration (r = 0.54; p < 0.01), while poor correlation was observed between iPad and the EMS for the translation (r = 0.28; p < 0.01). The ROC curve analysis demonstrated better accuracy for the detection of ACL insufficiency in the EMS than KiRA and iPad for tibial acceleration and translation, respectively.

CONCLUSIONS

Although all three measurements were similarly capable of detecting ACL deficiency, the EMS has the advantage of comprehensive evaluation of the pivot-shift test by evaluating both tibial acceleration and translation with higher accuracy than those of KiRA and iPad. It could be suggested that any of those measurement tools might improve the clinical diagnosis of ACL insufficiency.

LEVEL OF EVIDENCE

Diagnostic study of consecutive patients with a universally applied gold standard, Level Ib.

Correlation between quantitative pivot shift and generalized joint laxity: a prospective multicenter study of ACL ruptures

PURPOSE

To investigate whether an increased magnitude of quantitative rotatory knee laxity is associated with a greater level of generalized joint laxity in ACL-injured and contralateral knees.

METHODS

A total of 103 patients were enrolled across four international centers to undergo anatomic ACL reconstruction. Rotatory knee laxity was evaluated preoperatively, both in the awake state and under anesthesia, using the standardized pivot shift test. Two devices were used to quantify rotatory knee laxity; an inertial sensor, measuring the joint acceleration, and an image analysis system, measuring the lateral compartment translation of the tibia. The presence of generalized joint laxity was determined using the Beighton Hypermobility Score. The correlation between the level of generalized joint laxity and the magnitude of rotatory knee laxity was calculated for both the involved knee and the non-involved knee. Further, patients were dichotomized into low (0-4) or high (5-9) Beighton Score groups. Alpha was set at < 0.05.

RESULTS

Ninety-six patients had complete datasets, 83 and 13 in the low and high Beighton Score groups respectively. In anesthetized patients, there was a significant correlation between the degree of Beighton Score and quantitative pivot shift when analyzing the non-involved knee using the image analysis system (r = 0.235, p < 0.05). When analyzing the same knee, multivariate analysis adjusted for meniscal injury, age and gender revealed an increased odds ratio for patients with increased lateral compartment translation to be part of the high Beighton Score group (OR 1.86, 95% CI 1.10-3.17, p < 0.05). No other correlation was significant. When analyzing the dichotomized subgroups, no significant correlations could be established.

CONCLUSION

The findings in this study suggest that there is a weak correlation between generalized joint laxity and the contralateral healthy knee, indicating increased rotatory knee laxity in these patients. Generalized joint laxity does not appear to correlate with rotatory knee laxity in ACL-injured knees.

LEVEL OF EVIDENCE

Prospective cohort study; level of evidence, 2.

Over-the-top ACL Reconstruction Plus Extra-articular Lateral Tenodesis With Hamstring Tendon Grafts: Prospective Evaluation With 20-Year Minimum Follow-up

BACKGROUND

There are few published studies with very long-term follow-up of combined intra- and extra-articular anterior cruciate ligament (ACL) reconstruction.

PURPOSE

To analyze clinical and radiographic outcomes of over-the-top ACL reconstruction plus extra-articular lateral tenodesis with autologous hamstrings at minimum 20-year follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Of 60 originally eligible patients who underwent over-the-top ACL reconstruction with double-stranded hamstring tendon (leaving intact graft tibial insertions) and extra-articular lateral plasty (performed with the remnant part of tendons), 52 were prospectively evaluated at a minimum 20-year follow-up (mean follow-up, 24 years; 41 men, 11 women; mean age at time of surgery, 25.5 ± 7.6 years). Twenty-nine patients were available for prospective evaluations: clinical (Lysholm, Tegner, and objective International Knee Documentation Committee [IKDC]), instrumented (KT-2000), and radiographic (standard, long-standing, and Merchant views). Subjective KOOS (Knee injury and Osteoarthritis Outcome Score) and objective inertial sensor pivot-shift analysis (KiRA) were carried out at final follow-up. Twenty-three patients were investigated by phone interview for subjective Tegner score and documented complications, rerupture, or revision surgery.

RESULTS

At final follow-up, mean Lysholm score was 85.7 ± 14.6; median Tegner score, 4 (range, 3-5); sport activity resumption, 86.2%; and objective IKDC score, good or excellent in 86% of patients (31%, A; 55%, B). Only 3 of 26 patients (12%) had >5-mm manual maximum KT-2000 side-to-side difference. KiRA system documented positive pivot-shift (>0.9-m/s² tibial acceleration side-to-side difference) in these 3 of 26 patients (12%). Statistically significant changes were as follows: decrease in Tegner score from 7 (range, 6-8) at 5-year follow-up to 4 (range, 3-5) at 10 years ( P < .0001) and decrease in Lysholm score from 96.1 ± 7.3 at 10-year follow-up to 85.7 ± 14.6 at 20 years ( P = .0003). Radiographic evaluation demonstrated significant difference of medial joint space between injured and healthy knees in patients with concomitant medial meniscectomy (n = 8, 3.2 ± 0.6 vs 5.0 ± 1.8 mm, P = .0114). No significant differences were reported regarding lateral or patellofemoral joint space. One patient (2%) experienced rerupture, with 3 of 52 (5.8%) having a contralateral ACL injury (excluded from KT-2000 and radiographic evaluations). Overall, 4 of 29 clinical failures (objective IKDC, KT-2000) and 1 rerupture among 52 patients were registered at final follow-up.

CONCLUSION

Studied surgical technique demonstrated good results in laxity control at 20-year minimum follow-up. The lateral extra-articular plasty associated with ACL reconstruction did not generate lateral knee or patellofemoral osteoarthritis. The factor increasing osteoarthritis was meniscectomy.

Global rotation has high sensitivity in ACL lesions within stress MRI

PURPOSE

This study aims to objectively compare side-to-side differences of P-A laxity alone and coupled with rotatory laxity within magnetic resonance imaging, in patients with total anterior cruciate ligament (ACL) rupture.

METHODS

This prospective study enrolled sixty-one patients with signs and symptoms of unilateral total anterior cruciate ligament rupture, which were referred to magnetic resonance evaluation with simultaneous instrumented laxity measurements. Sixteen of those patients were randomly selected to also have the contralateral healthy knee laxity profile tested. Images were acquired for the medial and lateral tibial plateaus without pressure, with postero-anterior translation, and postero-anterior translation coupled with maximum internal and external rotation, respectively.

RESULTS

All parameters measured were significantly different between healthy and injured knees (P < 0.05), with exception of lateral plateau without stress. The difference between injured and healthy knees for medial and lateral tibial plateaus anterior displacement (P < 0.05) and rotation (P < 0.001) was statistically significant. It was found a significant correlation between the global rotation of the lateral tibial plateau (lateral plateau with internal + external rotation) with pivot-shift, and between the anterior global translation of both tibial plateaus (medial + lateral tibial plateau) with Lachman. The anterior global translation of both tibial plateaus was the most specific test with a cut-off point of 11.1 mm (93.8 %), and the global rotation of the lateral tibial plateau was the most sensitive test with a correspondent cut-off point of 15.1 mm (92.9 %).

CONCLUSION

Objective laxity quantification of ACL-injured knees showed increased sagittal laxity, and simultaneously in sagittal and transversal planes, when compared to their healthy contralateral knee. Moreover, when measuring instability from anterior cruciate ligament ruptures, the anterior global translation of both tibial plateaus and global rotation of the lateral tibial plateau add diagnostic specificity and sensitivity. This work strengthens the evidence that the anterior cruciate ligament plays an important biomechanical role in controlling the anterior translation, but also both internal and external rotation. The high sensitivity and specificity of this device in objectively identifying and measuring the multiplanar instability clearly guides stability restoration clinical procedures. Level of evidence Cross-sectional study, Level III.

Ultrasonographic Evaluation of Anterolateral Ligament Injuries: Correlation With Magnetic Resonance Imaging and Pivot-Shift Testing

PURPOSE

(1) To compare the diagnostic ability of ultrasonography (US) and magnetic resonance imaging (MRI) to detect anterolateral ligament (ALL) injuries in anterior cruciate ligament (ACL)-deficient patients, and (2) to evaluate the correlation between ALL injury status (as determined by US and MRI) and the knee's rotational stability.

METHODS

Thirty patients with an isolated ACL injury were included prospectively over a 3-month period. The condition of the ALL was evaluated by 2 experienced radiologists using both US and MRI. Rotational stability was evaluated by 2 surgeons with the pivot-shift test with patients under general anesthesia. It was classified as either negative (grades 0 and I) or positive (grades II and III). The radiologists were blinded to the knee's rotational stability, and the surgeons were blinded to the ALL's status based on the US images. The correlation between the ALL's injury status (US and MRI) and the pivot shift was determined with the Pearson χ² test. To evaluate the reproducibility of the results, the agreement between observers was determined with the Cohen κ coefficient.

RESULTS

On US, the ALL was identified and visible over its entire length in 100% of patients (30 of 30, κ = 1). The ALL was injured in 63% of patients (19 of 30, κ = 0.93). On MRI, the ALL was identified in 96% of patients (29 of 30, κ = 0.91). The ALL appeared injured in 53% of cases (16 of 30, κ = 0.93). An ALL that appeared injured on US was more often associated with a positive pivot shift than was an uninjured ALL (75% vs 39%, χ² = 13.7, P < .05). The interobserver agreement was high for both US (κ = 0.91-1) and MRI (κ = 0.76-1).

CONCLUSIONS

US is a reproducible examination for the diagnosis of ALL injury. An ALL injury is most often associated with a high pivot-shift grade.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Combined reconstruction of the anterior cruciate ligament associated with anterolateral tenodesis effectively controls the acceleration of the tibia during the pivot shift

PURPOSE

The pivot shift test is quantified subjectively during assessment of patients presenting with suspected Anterior Cruciate Ligament (ACL) tears and has a low interobserver reproducibility. The Kinematic Rapid Assessment (KiRA) is a triaxial accelerometer that makes it possible to non-invasively quantify tibial acceleration during the pivot shift test. Abolishing pivot shift is considered to be a key element in surgical reconstruction but is incomplete in 25-38% of patients.

METHODS

Patients were included prospectively. Inclusion criteria were patients requiring ACL reconstruction associated with at least one of the following factors corresponding to the patient who have a high risk of rupture either by their sports activity, a failure case, or the notion of important rotational laxity: the patient practiced a competitive pivot-contact sport, revision ACL reconstruction (besides STG (semitendinosus-gracilis graft) repair), subjective explosive rotational laxity, Segond fracture, and TELOS value of >10 mm. Standardized pre- and postoperative pivot shift tests were immediately performed under anesthesia in both knees.

RESULTS

Forty-three patients were included. Mean preoperative variations in tibial acceleration in the healthy and injured knees were 1.2 ± 0.1 and 2.7 ± 0.3 m/s², respectively, p < 0.01. A statistically significant decrease in immediate postoperative mean variations in acceleration in the injured knee occurred: 1.5 ± 0.3 m/s², p < 0.01. There was no longer any statistical difference between postoperative contralateral healthy knees and operated knees (n.s).

CONCLUSIONS

Combined ACL reconstruction associated with anterolateral tenodesis suppress acute pathologic tibial acceleration in the pivot shift.

LEVEL OF EVIDENCE

III.