Use of electromyographic biofeedback in rehabilitation following anterior cruciate ligament reconstruction: a systematic review and meta-analysis

BACKGROUND

Rehabilitation following anterior cruciate ligament (ACL) reconstruction surgery is essential to regain functionality and return to previous activity level. Electromyographic biofeedback may be an effective intervention for rehabilitation of patients following ACL surgery.

OBJECTIVE

To synthesize the available evidence on the effect of electromyographic biofeedback in the treatment of quadriceps strength following ACL surgery.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

PubMed, EMBASE, CENTRAL and Epistemonikos were searched.

ELIGIBILITY CRITERIA

Randomized clinical trials with patients undergoing ACL reconstruction surgery comparing biofeedback with a standard rehabilitation control group.

DATA EXTRACTION AND DATA SYNTHESIS

Two authors selected articles and performed data extraction. The analysed outcomes were strength, function, pain, knee extension and balance. The risk of bias of individual studies was assessed using the Cochrane Risk of Bias Tool. Results were combined through random-effects meta-analysis, reporting mean differences.

RESULTS

Eight articles were included in the qualitative analysis, and four articles were included in the quantitative analysis. The interventions lasted between 4 and 12 weeks. Three studies evaluated the effect of biofeedback on quadriceps strength; of these, two studies showed a significant difference in favour of the biofeedback group. In addition, biofeedback was found to improve knee extension [standardized mean difference - 1.3, 95% confidence interval (CI) - 1.74 to -0.86] and balance (one study). There was no significant difference in Lysholm score (mean difference -6.21, 95% CI -17.51 to 5.08; I2 =59%) or pain between the biofeedback group and the control group.

CONCLUSION

Electromyographic biofeedback in knee rehabilitation could be useful following ACL reconstruction surgery.

KEY MESSAGES

SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO (CRD42020193768).

The distance between the fibular collateral ligament tunnel and the common peroneal nerve allows a posterolateral corner reconstruction without neurolysis

PURPOSE

The most popular knee posterolateral corner (PLC) reconstruction techniques describe that a common peroneal nerve (CPN) neurolysis must be done to safely address the posterolateral aspect of the knee. The purpose of this study was to measure the distance between the CPN and the fibular insertion of the FCL in different degrees of knee flexion in cadaveric specimens, to identify if tunnel drilling could be done anatomically and safely without a CPN neurolysis.

METHODS

Ex vivo experimental analytical study. Ten fresh frozen human knees were dissected leaving FCL and CPN in situ. Shortest distance from the centre of the FCL distal tunnel and CPN was measured (antero-posterior and proximal-distal wire-nerve distances) at 90°, 60°, 30°, and 0° of knee flexion. Measurements between different flexion angles were compared and correlation between knee flexion angle and distance was identified.

RESULTS

The mean distance between the FCL tunnel and the CPN at 90° were 21.15 ± 6.74 mm posteriorly (95% CI: 16.33-25.97) and 13.01 ± 3.55 mm distally (95% CI: 10.47-15.55). The minimum values were 9.8 mm posteriorly and 8.9 mm, respectively. These distances were smaller at 0° (p ≤ 0.017). At 90° of knee flexion, the mean distance from the fibular tip to the CPN distally was 23.46 ± 4.13 mm (20.51-26.41).

CONCLUSION

Anatomic localization and orientation of fibular tunnels can be done safely while avoiding nerve neurolysis. Further studies should aim to in vivo measurements and results.

Tibial tubercle to trochlear groove and the roman arch method for tibial tubercle lateralisation are reliable and distinguish between subjects with and without major patellar instability

PURPOSE

Patellofemoral (PF) instability recurrence depends on several factors including the relative lateralisation of tibial tubercle (TT) regarding the trochlear groove (TG). TT relative lateralisation quantification has long been a topic of debate. Multiple measuring techniques have been described including TT-trochlear groove (TT-TG), TT-posterior cruciate ligament (TT-PCL) and TT-roman arch (TT-RA), with no clear consensus regarding the most reliable index or pathologic threshold. We set out to determine the normal value range of each index and their association with age, sex and PF instability status. Also, this study aims to determine a reliable pathologic distance threshold to effectively predict patellar dislocation.

METHODS

Skeletally mature patients up to 45 years of age who presented a CT Scan and an MRI of the same knee between 2014 and 2018 were included and divided into subgroups based on history of PF instability. Three indexes (TT-TG, TT-PCL and TT-RA) were assessed by two independent observers blinded to instability history. ROC curves were performed for each index to obtain the cut point that better predicts instability. Univariate and multivariate models adjusted by age, sex, instability history and type of imaging technique were performed to test the influence of these variables.

RESULTS

208 patients were included. Mean age was 27.93 ​± ​8.48 years, 67.3% were female and 71 patients (34.1%) presented major instability history. Good or excellent inter and intraobserver reliability was found for all three indexes. All indexes presented significantly different distributions between subjects with and without major instability (p ​< ​0.001), except for TT-PCL. Different cut point values differing between imaging modalities were found: 11.4 ​mm for MRI TT-TG, 17 ​mm for CT TT-TG, 15.6 ​mm for MRI TT-RA and 18.2 ​mm for CT TT-RA.

CONCLUSIONS

All indexes studied had good or excellent inter and intraobserver reliability. Measurements between imaging techniques (CT and MR) are not interchangeable. Both TT-TG and TT-RA correctly distinguish between subjects with and without major instability, while TT-PCL does not, recommending caution when evaluated on its own. Specific threshold values depending on imaging technique should be considered for surgical decision-making.

LEVEL OF EVIDENCE

Level IV, Diagnostic Test.

Evaluation of the Chilean National Orthopaedic Examination Over 11 Years: Progress and Outcomes of National and International Examinees

INTRODUCTION

The National Orthopaedics Examination (EMNOT) was initially designed for Chilean orthopaedic program graduates and is now a crucial component of the revalidation process for international orthopaedic surgeons seeking practice in Chile. This study aims to describe participation and performance of EMNOT examinees based on their origin and to analyze the difficulty and discrimination indexes during its first 11 years of implementation.

METHODS

A retrospective assessment was conducted on all EMNOT results from 2009 to 2019. The study evaluated the participation and performance of examinees according to their origin and examined the difficulty and discrimination indexes of the examination.

RESULTS

A total of 975 examinees were evaluated, with 41.23% from national resident programs (National Medical Graduates) and 58.77% from international examinees (International Medical Graduates). The number of participating universities increased from 4 in 2009 to 17 in 2019. National Medical Graduates examinees achieved a mean score of 66.52 ± 8.67 (0 to 100 points) while International Medical Graduates examinees scored 55.13 ± 11.42 (P < 0.001). The difficulty and discrimination indexes remained adequate throughout this period.

DISCUSSION

Over the course of 11 years, the number of EMNOT examinees exhibited notable growth. The examination effectively differentiates between candidates based on their origin and maintains appropriate levels of difficulty and discrimination.

Skyline view of the patella does not increase fracture detection: A non-inferiority diagnostic study

PURPOSE

Patella fractures are frequent injuries in the adult population. Initial study is made by plain radiographs and the standard set includes the skyline view of patella. Recommendation for use of this projection is variable among the experts, without data that support its performance in the diagnosis of patella fractures. The main purpose of this study was to determine the sensitivity of the antero-posterior and lateral view of the knee, without skyline view, in the diagnosis of patella fracture.

METHODS

A retrospective non-inferiority diagnostic study was designed with all the knee trauma adult patients of an Emergency Department in a single center in five years. A random sample of all the consecutive patella fracture cases were taken to elaborate the case group. The control group was matched by sex and age. Two blinded orthopedic surgeons reviewed the cases and control radiographs and defined the presence of fracture, with or without skyline view, with a wash-out time of three weeks between the two evaluations. Non-inferiority was defined a priori at 90% of minimum sensitivity.

RESULTS

140 patients were evaluated (70 cases and 70 controls). Sensitivity of the set without skyline view was 92.86% (CI 95% 0.90 - 0.96) and the standard set was 97.86% (CI 95% 0.96 - 0.99), without significant differences (p = 0.1) CONCLUSION: Sensitivity of the plain radiograph set without skyline view is non-inferior to the standard set. The routine use of skyline view when suspecting patella fractures is questionable.

The AO classification system for tibial plateau fractures: An independent inter and intraobserver agreement study

PURPOSE

Classifying tibial plateau fractures is paramount in determining treatment regimens and systemizing decision making. The original AO classification described by Müller in 1996 and the Schatzker classification of 1970 are the most cited classifications for tibial plateau fractures, demonstrating substantial to almost perfect agreement. The main problem with these classifications schemes is that they lack the detail required to convey the variety of fracture patterns encountered. In 2018, the AO foundation published a new classification system for proximal tibia fractures, highlighting a more complete and detailed number of categories and subcategories. We sought to independently determine inter and intraobserver agreement of the AO classification system, compared to the previous systems described by Müller and Schatzker.

METHODS

One hundred seven consecutive tibial plateau fractures were screened, and a representative data set of 69 was created. Six independent evaluators (three knee surgeons, three senior orthopedic residents) classified the fractures using the original AO, the Schatzker and the new AO classifications. After six weeks, the 69 cases were randomized and reclassified by all evaluators. The Kappa coefficient (k) was calculated for inter- and intraobserver correlation and is expressed with 95% confidence intervals.

RESULTS

interobserver agreement was moderate for all three classifications. k = 0.464 (0.383-0.560) for the original AO; k = 0.404 (0.337-0.489) for Schatzker; and k = 0.457 (0.371-0.545) for the base categories of the new AO classification. The inclusion of subcategories and letter modifiers to the new classification worsened agreement to k = 0.358 (0.302-0.423) and k = 0.174 (0.134-0.222), respectively. There were no significant differences between knee surgeons and residents for the new classification. Intra-observer correlation was also moderate for each of the scores: k = 0.630 (0.578-0.682) for the original AO; k = 0.623 (0.569-0.674) for Schatzker; and k = 0.621 (0.566-0.678) for the new AO base categories; without differences between knee surgeons or residents.

CONCLUSIONS

This study demonstrated an adequate inter and intra-observer agreement for the new AO tibial plateau fractures classification system for its base categories, but not at the subcategory or letter modifier levels.

Tibial Cut Accuracy in Mechanically Aligned Total Knee Arthroplasty Using Extensor Hallucis Longus Tendon to Determine Extramedullary Tibial Guide Position

This study aimed to determine the tibial cut (TC) accuracy using extensor hallucis longus (EHL) tendon as an anatomical landmark to position the total knee arthroplasty (TKA) extramedullary tibial guide (EMTG), and its impact on the TKA mechanical alignment (MA). We retrospectively studied 96 TKA, performed by a single surgeon, using a femoral tailored intramedullary guide technique. Seventeen were prior to the use of the EHL and 79 used the EHL tendon to position the EMTG. We analyzed preoperative and postoperative standing total lower extremity radiographs to determine the tibial component angle (TCA) and the correction in MA, comparing pre-EHL use and post-EHL technique incorporation. Mean TCA was 88.89 degrees and postoperative MA was neutral in 81% of patients. Pre- and postoperative MAs were not correlated. As a conclusion of this study, using the EHL provides a safe and easy way to determine the position of EMTG.

Finite element modeling of multiple density materials of bone specimens for biomechanical behavior evaluation

The finite elements method allied with the computerized axial tomography (CT) is a mathematical modeling technique that allows constructing computational models for bone specimens from CT data. The objective of this work was to compare the experimental biomechanical behavior by three-point bending tests of porcine femur specimens with different types of computational models generated through the finite elements’ method and a multiple density materials assignation scheme. Using five femur specimens, 25 scenarios were created with differing quantities of materials. This latter was applied to computational models and in bone specimens subjected to failure. Among the three main highlights found, first, the results evidenced high precision in predicting experimental reaction force versus displacement in the models with larger number of assigned materials, with maximal results being an R2 of 0.99 and a minimum root-mean-square error of 3.29%. Secondly, measured and computed elastic stiffness values follow same trend with regard to specimen mass, and the latter underestimates stiffness values a 6% in average. Third and final highlight, this model can precisely and non-invasively assess bone tissue mechanical resistance based on subject-specific CT data, particularly if specimen deformation values at fracture are considered as part of the assessment procedure.

Offloader knee braces for knee osteoarthritis

INTRODUCTION Knee osteoarthritis is a relevant health problem given its high prevalence and associated disability. Within the non-pharmacological management alternatives, the use of offloader knee braces has been proposed, however, there is no consensus in the literature regarding its indication. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified 14 systematic reviews including nine studies overall, all of which were randomized trials. We conclude that the use of offloader knee braces in patients with knee osteoarthritis probably increases physical function through walking distance. However, its use may make little or no difference to physical function measured with the Hospital for Special Surgery Knee score, it may slightly worsen the quality of life and increase adverse events, but the certainty of the evidence is low. In addition, we are uncertain whether the use of offloader knee braces reduces pain as the certainty of the evidence has been assessed as very low.

Offloader knee braces for knee osteoarthritis

INTRODUCTION

Knee osteoarthritis is a relevant health problem given its high prevalence and associated disability. Within the non-pharmacological management alternatives, the use of offloader knee braces has been proposed, however, there is no consensus in the literature regarding its indication.

METHODS

We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSIONS

We identified 14 systematic reviews including nine studies overall, all of which were randomized trials. We conclude that the use of offloader knee braces in patients with knee osteoarthritis probably increases physical function through walking distance. However, its use may make little or no difference to physical function measured with the Hospital for Special Surgery Knee score, it may slightly worsen the quality of life and increase adverse events, but the certainty of the evidence is low. In addition, we are uncertain whether the use of offloader knee braces reduces pain as the certainty of the evidence has been assessed as very low.

Medial opening wedge high tibial osteotomy: more than ten years of experience with Puddu plate technique supports its indication

PURPOSE

To describe the short-term and long-term results of patients who underwent a medial opening wedge high tibial osteotomy (MOW-HTO) for unicompartmental medial knee joint osteoarthritis.

METHODS

A retrospective review was conducted of patients with MOW-HTO using a Puddu plate®, with more than ten year follow-up. The degree of correction, initial chondral damage, number of meniscal lesions, preoperative and 1-year postoperative functional scale scores (IKDC and Lysholm), and arthroplasty conversion rates at the ten year follow-up were registered. We assumed early indication when patients underwent the operation before they were 40 years old and delayed ≥ 40. Functional outcomes were analyzed by adjusting for pre-operative values. Fisher's exact test was used to study the association between the arthroplasty conversion rates and the timing of indication.

RESULTS

Fifty-five patients were included, 37 of whom were male (67%). Twenty-nine patients had early indications for surgery (53%). All patients completed ten year follow-up. All patients improved IKDC (p < 0.01) and Lysholm (p < 0.01) scores compared to their presurgical scores at the one year post-operative evaluation. We had six minor complications, none requiring revision surgery. We had three conversions to arthroplasty, all in the late indication group, not statistically significant different. Linear regression showed that early indication was associated with a higher IKDC score when adjusting for the Outerbridge chondral damage score, the number of meniscal lesions, and sex (p < 0.01).

CONCLUSION

All patients improved functional scores one year after surgery. Early indication (i.e., younger than 40 years of age) was independently associated with better functional outcomes than late indication at one year follow-up.

Contralateral canes for knee osteoarthritis

Introduction

Knee osteoarthritis is a relevant health problem given its high prevalence and associated disability. Within the non-pharmacological management alternatives, the use of canes has been proposed, however, there is no consensus in the literature regarding its indication.

Methods

We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

Results and conclusions

We identified three systematic reviews including four studies overall, of which one was randomized trials. We conclude that the use of a contralateral cane in patients with knee osteoarthritis probably reduces pain. In addition, it could slightly increase function, but the certainty of the evidence is low.

Weight loss exclusively through diet for knee osteoarthritis

INTRODUCTION

Knee osteoarthritis is a highly prevalent chronic disease, associated with various risk factors and with multiple treatment options. Overweight is among the main risk factors and also constitutes an aggravating factor of the symptoms. It has been suggested that weight loss would be able to improve symptoms and to stop the progression. It can be achieved by several methods: exercise, diet, drugs, surgery, or a combination of them. Apparently, diet is a reasonable option given its availability, low technical complexity and greater acceptability, especially in the population susceptible to developing knee osteoarthritis, but it is not clear whether the benefit of diet as the only intervention leads to symptomatic improvement.

METHODS

We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSIONS

We identified seven systematic reviews including six primary studies overall, all corresponding to randomized trials. We concluded diet may improve functionality and quality of life, with probably minimal or no adverse effects. However, we are uncertain whether diet reduces pain as the certainty of the evidence has been assessed as very low.

Non-uniform strain distribution in anterolateral capsule of knee: Implications for surgical repair

The existence of a ligamentous structure within the anterolateral capsule, which can be injured in combination with the anterior cruciate ligament, has been debated. Therefore, the purpose of this study was to determine the magnitude and direction of the strain in the anterolateral capsule in response to external loads applied to the knee. The anterolateral capsule was hypothesized to not function like a traditional ligament. A 6-degree-of-freedom robotic testing system was used to apply ten external loads to human cadaveric knees (n = 7) in the intact and anterior cruciate ligament (ACL) deficient states. The position of strain markers was recorded on the midsubstance of the anterolateral capsule during the resulting joint kinematics to determine the magnitude and direction of the maximum principal strain. The peak maximum principal strain ranged from 22% to 52% depending on the loading condition. When histograms of strain magnitude values were analyzed to determine strain uniformity, the mean kurtosis was 1.296 ± 0.955, lower than a typical ligament, and the mean variance was 0.015 ± 0.008, higher than a typical ligament. The mean angles of the strain direction vectors compared to the proposed ligament ranged between 38° and 130° (p < 0.05). The magnitude of the maximum principal strain in the anterolateral capsule is much larger than a typical ligament and does not demonstrate a uniform strain distribution. The direction of strain is also not aligned with the proposed ligament. Clinical Significance: Reconstruction methods using tendons will not produce normal joint function due to replacement of a multi-axial structure with a uni-axial structure. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

What are the benefits and risks of total arthroplasty in arthrodesed knees?

INTRODUCTION

The conversion of a previously arthrodesed knee to a total knee arthroplasty is an alternative seldom used. However, arthroplasty would provide greater functionality to the arthrodesed joint. Since it is a technically demanding procedure, not exempt from complications, there is controversy about the role of this intervention.

METHODS

To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSIONS

We identified two systematic reviews including 10 studies overall, none of which corresponded to a randomized trial. We concluded the conversion of knee arthrodesis to total knee arthroplasty could increase the functionality, but it is not clear whether it increases the complications or if it has any impact on pain or patient satisfaction because the certainty of the evidence is very low.

Is duloxetine an alternative in the treatment of osteoarthritis?

INTRODUCTION

Many osteoarthritis patients continue to present symptoms despite nonsurgical treatment. Duloxetine might be a viable alternative for such cases, but real clinical relevance remains unclear.

METHODS

A literature review was conducted in Epistemonikos, the largest database for systematic reviews in health that compiles multiple sources, including MEDLINE, EMBASE, and Cochrane, among others. Relevant data were extracted, and information from the primary studies was reanalyzed. A subsequent meta-analysis was conducted, and summary of findings tables were constructed using the GRADE methodology.

RESULTS AND CONCLUSIONS

Four systematic reviews including four randomized trials, were identified. In conclusion, while duloxetine slightly improves pain and functionality in osteoarthritis patients, its use is associated with frequent adverse side effects. Therefore, the benefit/risk balance appears unfavorable.

Is diacerein an alternative for the treatment of osteoarthritis?

INTRODUCTION

Among the possibilities for the management of osteoarthritis, different pharmacological alternatives have been proposed, being diacerein one of them due to its anti-inflammatory effect. However, diacerein clinical utility is not clear.

METHODS

To answer this question, we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSION

We concluded diacerein may lead to a slight reduction in pain and probably not improve functionality among patients with knee osteoarthritis and can frequently present diarrhea as an adverse effect. [corrected].

The Role of Extra-Articular Tenodesis in Combined ACL and Anterolateral Capsular Injury

BACKGROUND

The "gold standard" treatment of anterolateral capsular injuries in anterior cruciate ligament (ACL)-deficient knees has not been determined. The purpose of this study was to determine the effects of ACL reconstruction and extra-articular reconstruction on joint motion in the ACL-deficient knee and in the combined ACL and anterolateral capsule-deficient knee.

METHODS

An anterior tibial load of 134 N and internal tibial torque of 7 Nm were applied to 7 fresh-frozen cadaveric knees using a robotic testing system continuously throughout the range of flexion. The resulting joint motion was recorded for 6 knee states: intact, ACL-deficient, ACL-reconstructed, combined ACL and anterolateral capsule-deficient, ACL-reconstructed + anterolateral capsule-deficient, and ACL-reconstructed + extra-articular tenodesis.

RESULTS

Anterior tibial translation of the ACL-reconstructed + anterolateral capsule-deficient knee in response to an anterior tibial load was restored to that of the intact knee at all knee-flexion angles (p > 0.05). However, for this knee state, internal tibial rotation in response to internal tibial torque was not restored to that of the intact knee at 60° or 90° of knee flexion (p < 0.05). For the knee state of ACL-reconstructed + extra-articular tenodesis, internal rotation in response to internal tibial torque was restored to the motion of the intact knee at each of the tested knee-flexion angles (p > 0.05). Compared with the intact knee, 2 of 7 specimens showed decreased internal tibial rotation with ACL reconstruction + extra-articular tenodesis.

CONCLUSIONS

In this study, an extra-articular tenodesis was necessary to restore rotatory knee stability in response to internal tibial torque in a combined ACL and anterolateral capsule-deficient knee. The amount of rotatory knee instability should be carefully assessed to avoid over-constraint of the knee in these combined ligament-reconstruction procedures.

CLINICAL RELEVANCE

On the basis of our findings, the surgical procedure needs to be personalized depending on the amount of rotatory knee instability in the injured knee and the amount of rotation in the contralateral knee.

Does anatomic single-bundle ACL reconstruction using hamstring autograft produce anterolateral meniscal root tearing?

Background

To determine if tibial tunnel reaming during anatomic single-bundle anterior cruciate ligament (ACL) reconstruction using hamstring autograft can result in anterolateral meniscal root injury, as diagnosed by magnetic resonance imaging (MRI).

Methods

A case series of 104 primary anatomic single-bundle ACL reconstructions using hamstring autograft was retrospectively reviewed. Pre- and post-operative (>1 year) MRIs were radiologically evaluated for each patient, with a lateral meniscus extrusion > 3 mm at the level of the medial collateral ligament midportion on a coronal MRI, to establish anterolateral meniscal root injury.

Results

No patients presented radiological findings of anterolateral meniscal root injury in this case series.

Conclusions

Examining a single-bundle ACL reconstruction technique using hamstring autograft that considered tibial tunnel positioning in the center of the tibial footprint, this case series found no evidence of anterolateral meniscal root injury in patient MRIs, even more than 1-year post-operation.

Is chondroitin sulfate effective for osteoarthritis?

Osteoarthritis is the most prevalent chronic articular disease, in which pain is one of the main symptoms and the major determinant of functional loss. Several therapeutic options have been proposed, including chondroitin sulfate, but its actual usefulness has not yet been established. To answer this question we searched in Epistemonikos database, which is maintained by screening multiple information sources. We identified 13 systematic reviews including 50 randomized trials overall. We extracted data, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. We concluded it is not clear whether the use of chondroitin sulfate leads to an improvement in pain or functionality in osteoarthritis because the certainty of the evidence is very low.

The Anterolateral Capsule of the Knee Behaves Like a Sheet of Fibrous Tissue

BACKGROUND

The function of the anterolateral capsule of the knee has not been clearly defined. However, the contribution of this region of the capsule to knee stability in comparison with other anterolateral structures can be determined by the relative force that each structure carries during loading of the knee. Purpose/Hypothesis: The purpose of this study was to determine the forces in the anterolateral structures of the intact and anterior cruciate ligament (ACL)-deficient knee in response to an anterior tibial load and internal tibial torque. It was hypothesized that the anterolateral capsule would not function like a traditional ligament (ie, transmitting forces only along its longitudinal axis).

STUDY DESIGN

Controlled laboratory study.

METHODS

Loads (134-N anterior tibial load and 7-N·m internal tibial torque) were applied continuously during flexion to 7 fresh-frozen cadaveric knees in the intact and ACL-deficient state using a robotic testing system. The lateral collateral ligament (LCL) and the anterolateral capsule were separated from the surrounding tissue and from each other. This was done by performing 3 vertical incisions: lateral to the LCL, medial to the LCL, and lateral to the Gerdy tubercle. Attachments of the LCL and anterolateral capsule were detached from the underlying tissue (ie, meniscus), leaving the insertions and origins intact. The force distribution in the anterolateral capsule, ACL, and LCL was then determined at 30°, 60°, and 90° of knee flexion using the principle of superposition.

RESULTS

In the intact knee, the force in the ACL in response to an anterior tibial load was greater than that in the other structures ( P < .001). However, in response to an internal tibial torque, no significant differences were found between the ACL, LCL, and forces transmitted between each region of the anterolateral capsule after capsule separation. The anterolateral capsule experienced smaller forces (~50% less) compared with the other structures ( P = .048). For the ACL-deficient knee in response to an anterior tibial load, the force transmitted between each region of the anterolateral capsule was 434% greater than was the force in the anterolateral capsule ( P < .001) and 54% greater than the force in the LCL ( P = .036) at 30° of flexion. In response to an internal tibial torque at 30°, 60°, or 90° of knee flexion, no significant differences were found between the force transmitted between each region of the anterolateral capsule and the LCL. The force in the anterolateral capsule was significantly smaller than that in the other structures at all knee flexion angles for both loading conditions ( P = .004 for anterior tibial load and P = .04 for internal tibial torque).

CONCLUSION

The anterolateral capsule carries negligible forces in the longitudinal direction, and the forces transmitted between regions of the capsule were similar to the forces carried by the other structures at the knee, suggesting that it does not function as a traditional ligament. Thus, the anterolateral capsule should be considered a sheet of tissue.

CLINICAL RELEVANCE

Surgical repair techniques for the anterolateral capsule should restore the ability of the tissue to transmit forces between adjacent regions of the capsule rather than along its longitudinal axis.

Comparison of graft bending angle during knee motion after outside-in, trans-portal and trans-tibial anterior cruciate ligament reconstruction

PURPOSE

To determine graft bending angle (GBA) during knee motion after anatomic anterior cruciate ligament (ACL) reconstruction and to clarify whether surgical techniques affect GBA. Our hypotheses were that the graft bending angle would be highest at knee extension and the difference of surgical techniques would affect the bending steepness.

METHODS

Eight healthy volunteers with a mean age of 29.3 ± 3.0 years were recruited and 3D MRI knee models were created at three flexion angles (0°, 90° and 130°). Surgical simulation of the tunnel drilling was performed with anatomic tunnel position using each outside-in (OI), trans-portal (TP) and trans-tibial (TT) techniques on the identical cases. The models were matched to other knee positions and the GBA in 3D was measured using computational software. Double-bundle ACL reconstruction was analysed first, and single-bundle reconstruction was also analysed to evaluate its effect to reduce GBA. A repeated-measures ANOVA was used to compare GBA difference at three flexion angles, by three techniques or of three bundles.

RESULTS

GBA changed substantially with knee motion, and it was highest at full extension (p < 0.001) in each surgical technique. OI technique exhibited highest GBA for anteromedial bundle (94.3° ± 5.2°) at extension, followed by TP (83.1° ± 6.5°) and TT (70.0° ± 5.2°) techniques (p < 0.01). GBA for posterolateral bundle at extension were also high in OI (84.6° ± 7.4°), TP (83.0° ± 6.3°) and TT (77.2° ± 7.0°) techniques (n.s.). Single-bundle grafts did not decrease GBA compared with double-bundle grafts. In OI technique, a more proximal location of the femoral exit reduced GBA of each bundle at extension and 90° flexion.

CONCLUSION

A significant GBA change with knee motion and considerably steep bending at full extension, especially with OI and TP techniques, were simulated. Although single-bundle technique did not reduce GBA as seen in double-bundle technique, proximal location of femoral exits by OI technique, with tunnels kept in anatomic position, was effective in decreasing GBA at knee extension and flexion. For clinical relevance, high stress on graft and bone interface has been suggested by steep GBA at full extension after anatomic ACL reconstruction.

LEVEL OF EVIDENCE

Therapeutic study (prospective comparative study), Level II.

Anatomical Individualized ACL Reconstruction

The anterior cruciate ligament (ACL) is composed of two bundles, which work together to provide both antero-posterior and rotatory stability of the knee. Understanding the anatomy and function of the ACL plays a key role in management of patients with ACL injury. Anatomic ACL reconstruction aims to restore the function of the native ACL. Femoral and tibial tunnels should be placed in their anatomical location accounting for both the native ACL insertion site and bony landmarks. One main component of anatomical individualized ACL reconstruction is customizing the treatment according to each patient's individual characteristics, considering preoperative and intraoperative evaluation of the native ACL and knee bony anatomy. Anatomical individualized reconstruction surgery should also aim to restore the size of the native ACL insertion as well. Using this concept, while single bundle ACL reconstruction can restore the function of the ACL in some patients, double bundle reconstruction is indicated in others to achieve optimal outcome.

[Cerebrotendinous xanthomatosis: report of one case]

Cerebrotendinous xanthomatosis is an inherited autosomal recessive disease caused by a mutation in the gene for the sterol 27-hydroxylase enzyme, which determines the accumulation of plasmatic cholestanol in various tissues. The natural history of this disease is characterized by chronic diarrhea beginning in childhood, cataract in youth, tendinous xanthomas in adulthood and later progressive neurological dysfunction manifested as dementia, psychiatric disorders, cerebellar, pyramidal or extra pyramidal signs or seizures. We report a 39 year-old male with a history of diarrhea during childhood and bilateral cataracts requiring surgery at 20 years of age, who evolves later with psychiatric disorders and bilateral increased volume in Achules tendons. High levels of plasmatic cholestanol and magnetic resonance imaging confirmed the diagnosis of this disease.