Neuromuscular electrical stimulation is effective in strengthening the quadriceps muscle after anterior cruciate ligament surgery

Four-year comparative analysis of return to sport and psychological recovery following ACL revision: Artificial ligament vs. anterior tibial tendon allograft

Background

Research on return to sport and psychological recovery in anterior cruciate ligament (ACL) revision remains scarce. The clinical efficacy of artificial ligament in ACL revision requires further exploration. Our objectives were (1) to compare the midterm clinical outcomes of artificial ligament versus allogenic tendon graft in ACL revision and (2) to analyze the effects of employing artificial ligament on return to sport and psychological recovery in ACL revision.

Methods

This cohort study included the cases receiving ACL revision from 2014 to 2021 in Sports Medicine Department of Huashan Hospital. The grafts used were Ligament Advanced Reinforcement System (LARS) and ATT allograft. We recorded patients' baseline data. The final follow-up assessment included subjective scales, physical examination, and return to sport status. We recorded the rates and timings of return to sport. Subjective scales included the 2000 International Knee Documentation Committee (IKDC) subjective score, Lysholm Knee Scaling Score (LKSS), Knee injury and Osteoarthritis Outcome Score (KOOS), Tegner activity score, Marx activity rating score, and Anterior Cruciate Ligament-Return to Sport after Injury (ACL-RSI). Anterior knee stability was assessed using the KT-1000 arthrometer.

Results

Fifty cases (LARS group: 27; ATT group: 23) enrolled and 45 (LARS group: 23; ATT group: 22) completed evaluations with a median follow-up period of 49 months. At recent follow-up, LARS group outperformed in knee stability (1.0 ± 1.9 mm vs. 2.6 ± 3.0 mm, P = 0.039), confidence (86.7 ± 12.4 vs. 69.4 ± 18.6, P < 0.001), emotion (82.7 ± 11.3 vs. 70.7 ± 16.2, P < 0.001), KOOS knee function (78.7 ± 8.8 vs. 69.5 ± 11.0, P = 0.003), quality of life (79.1 ± 16.1 vs. 66.4 ± 19.5, P = 0.014), Tegner score (6.3 ± 1.9 vs. 5.2 ± 2.1, P < 0.001), and Marx activity score (10.7 ± 3.7 vs. 7.9 ± 4.0, P = 0.012). The LARS group had significantly higher return rates: recreational (91.3 % vs. 63.6 %, P = 0.026), knee cutting and pivoting (87.0 % vs. 59.1 %, P = 0.035), competitive (78.3 % vs. 45.5 %, P = 0.023), and pre-injury (56.5 % vs. 27.3 %, P = 0.047). For return timings, the LARS group was earlier at recreational (11.2 ± 3.9 vs. 27.8 ± 9.0 weeks, P < 0.001), knee cutting and pivoting (17.2 ± 5.8 vs. 35.6 ± 13.8 weeks, P < 0.001), competitive (24.8 ± 16.2 vs. 53.2 ± 22.0 weeks, P < 0.001), and pre-injury levels (32.8 ± 11.0 vs. 72.8 ± 16.9 weeks, P < 0.001).

Conclusion

In ACL revision, using LARS demonstrated improved joint stability and functionality compared to using allogenic ATT four years postoperative. Patients accepting the LARS procedure exhibited higher rates and earlier timings of return to various levels of sport, indicating enhanced confidence and emotional resilience.

The translational potential of this article

In ACL revision, the choice of artificial ligament to shorten recovery time, thereby enabling patients to return to sport more quickly and effectively, is thought-provoking. The research value extends beyond mere graft selection, guiding future clinical trials and studies. This research enhances our understanding of the application value of artificial ligament in ACL revision, emphasizing the importance of psychological recovery and updating our perceptions of return to sport levels post-revision. It stimulates exploration into personalized rehabilitation programs and treatment strategies, aiming to optimize clinical outcomes and meet the real-world needs of patients with failed ACL reconstruction.

Neuromuscular electrical stimulation for the treatment of diabetic sensorimotor polyneuropathy: A prospective, cohort, proof-of-concept study

OBJECTIVE

To assess a potential efficacy signal, safety and feasibility of neuromuscular electrical stimulation (NMES) therapy as an adjunct to standard care in patients with diabetic sensorimotor polyneuropathy (DSPN).

METHODS

In this single-centre, prospective, cohort, proof-of-concept study, 25 patients with DSPN consented to at least one daily 30-minute NMES therapy session (Revitive® IX) for 10 weeks, with 20 patients completing the study. The primary outcome measure was nerve conductivity assessed using a nerve conduction study of the sural, superficial peroneal, common peroneal and tibial nerves at 10 weeks compared to baseline. Secondary outcomes included superficial femoral artery (SFA) haemodynamics during NMES therapy compared to rest and quality-of-life at 10 weeks compared to baseline.

RESULTS

At 10 weeks, there were significant increases in sural sensory nerve action potential amplitude and conduction velocity (p < 0.001), superficial peroneal sensory nerve action potential amplitude (p = 0.001) and conduction velocity (p = 0.002), common peroneal nerve conduction velocity (p = 0.004) and tibial nerve compound muscle action potential amplitude (p = 0.002) compared to baseline. SFA volume flow and time-averaged mean velocity significantly increased (p ≤ 0.003) during NMES compared to rest. Patient-reported Michigan Neuropathy Screening Instrument scores significantly decreased (p = 0.028) at 10 weeks compared to baseline. Three unrelated adverse events occurred, and 15 participants adhered to treatment.

CONCLUSIONS

NMES therapy as an adjunct to standard care for 10 weeks significantly increased lower limb nerve conductivity in patients with DSPN and may be beneficial in the treatment of DSPN.

Nurse-Assisted Rehabilitation Protocols Following Anterior Cruciate Ligament Reconstruction

Despite significant advancements in surgical instruments and operation skills, short- and long-term outcomes following anterior cruciate ligament reconstruction (ACLR) remain unsatisfactory, as many patients fail to return to their pre-injury level of sports. Inadequate ACL rehabilitation is the primary cause of poor outcomes. Nurses have become a crucial element in the rehabilitation process. Although there is no consensus regarding the optimal post-operative rehabilitation protocols, restoring muscle strength and neuromuscular control are consistently the primary goals. This literature review presents nurse-assisted rehabilitation protocols aiming at improving muscle strength and neuromuscular control. The review discusses postoperative rehabilitation, including home-based and supervised rehabilitation, open and closed kinetic chain exercises, eccentric and concentric training, blood flow restriction training, and plyometric training. Each training protocol has its benefits and drawbacks, and should be used cautiously in specific stages of rehabilitation. Neuromuscular training, such as neuromuscular electrical stimulation, neuromuscular control exercises, and vibration therapy, is considered crucial in rehabilitation.

The past and future of peri-operative interventions to reduce arthrogenic quadriceps muscle inhibition after total knee arthroplasty: A narrative review

Total knee arthroplasty (TKA) improves patient-reported function by alleviating joint pain, however the surgical trauma exacerbates already impaired muscle function, which leads to further muscle weakness and disability after surgery. This early postoperative strength loss indicates a massive neural inhibition and is primarily driven by a deficit in quadriceps muscle activation, a process known as arthrogenic muscle inhibition (AMI). To enhance acute recovery of quadriceps muscle function and long-term rehabilitation of individuals after TKA, AMI must be significantly reduced in the early post-operative period. The aim of this narrative review is to review and discuss previous efforts to mitigate AMI after TKA and to suggest new approaches and interventions for future efficacy evaluation. Several strategies have been explored to reduce the degree of post-operative quadriceps AMI and improve strength recovery after TKA by targeting post-operative swelling and inflammation or changing neural discharge. A challenge of this work is the ability to directly measure AMI and relevant contributing factors. For this review we focused on interventions that aimed to reduce post-operative swelling or improve knee extension strength or quadriceps muscle activation measured by twitch interpolation. For individuals undergoing TKA, the use of anti-inflammatory medications, tranexamic acid, cryotherapy, intra-articular drains, torniquets, and minimally invasive surgical techniques for TKA have limited benefit in attenuating quadriceps AMI early after surgery. However, interventions such as inelastic compression garments, voluntary muscle contractions, and neuro-muscular electrical stimulation show promise in mitigating or circumventing AMI and should continue to be refined and explored.

[Current approach in the follow-up treatment of joint-preserving operations on the knee joint in German-speaking countries]

INTRODUCTION

Postoperative follow-up after joint-preserving knee surgery involves conventional physiotherapy as well as other approaches and devices such as CPM and CAM splints, TENS devices, BFR exercise, prehabilitation, and digital health applications. The aim of this survey was to investigate current standards, trends and control methods in postoperative care to identify fields of concern and to compare them with the current literature.

MATERIAL AND METHODS

We conducted a structured anonymous online survey of specialists in orthopaedics and trauma surgery listed by the German-speaking Society for Arthroscopy and Joint Surgery (AGA). The questionnaire included 36 closed-ended questions on the follow-up of joint-preserving surgery of the knee joint.

RESULTS

Questionnaires from 528 participants with long-term professional experience (86.6% with more than 10 years) were analysed. Standardised post-treatment schemes are used by 97.2% and their evidence is estimated to be high (59.1%) / very high (14.8%). Problems of rehabilitation are seen in 10-20% of cases by 87.3% (persistent muscular atrophy 30.9%). After reconstructive surgery, CPM splints (70.1%), CAM splints (42.1%), orthoses (85.0%) and TENS devices (40.0%) are prescribed. More potent approaches for the treatment of postoperative muscle deficits are desired by 89.4%. BFR exercise is known by 41.7% and is used regularly by 8%. Communication with treating physiotherapists is infrequent (written: 27.5%). Digital rehabilitation management would be supported by 83.3%; 22.7% are not aware of digital health applications. 87.9% of participants believe that prehabilitation can affect postoperative outcomes.

CONCLUSION

Follow-up of knee joint-preserving surgeries is usually standardised and regularly reviewed for up-to-date evidence. The evidence for recommendations made is considered high. Orthoses are usually used after reconstructive surgery, persistent muscle atrophy is a major problem, BFR training is only known to a limited extent, and there is currently a lack of standardised training protocols. Communication with physiotherapists needs to be improved. Digital rehabilitation management is rarely used but would be supported by the majority of surgeons.

Optimising the Early-Stage Rehabilitation Process Post-ACL Reconstruction

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

On Putting an End to the Backlash Against Electrophysical Agents

Electrophysical agents (EPAs) are core therapeutic interventions in academic physical therapy curricula around the world. They are used concomitantly with several other therapeutic interventions such as exercise, manual therapy techniques, medications, and surgery for the management of a wide variety of soft tissue disorders. Over the past decade, the practice of EPAs has been the subject of intense scrutiny in the U.S. This has been colored by some physical therapists publicly engaging in bashing rhetoric that has yet to be officially and publicly addressed by the guiding organizations which, together, regulate the practice of physical therapy in this country. Published in world renowned public media are unsubstantiated mocking remarks against the practice of EPAs and unethical allegations against its stakeholders. This rhetoric suggests that EPA interventions are "magical" treatments and that those practitioners who include them in their plans of care may be committing fraud. Such bashing rhetoric is in striking contradiction to the APTA's Guide to Physical Therapist Practice 4.0, which lists EPAs as one of its categories of interventions, the CAPTE's program accreditation policy, and the FSBPT's national licensing exam. The purpose of this commentary is to expose the extent of this discourse and to call to action the APTA, CAPTE, and FSBPT organizations, as well as physical therapists, with the aim at putting an end to this rhetoric.

Effect of neuromuscular electrical stimulation combined with early rehabilitation therapy on mechanically ventilated patients: a prospective randomized controlled study

BACKGROUND

This study aimed to investigate the effectiveness of neuromuscular electrical stimulation (NMES) blended with early rehabilitation on the diaphragm and skeletal muscle in sufferers on mechanical ventilation (MV).

METHOD

This is a prospective randomized controlled study. Eighty patients on MV for respiratory failure were divided into a study group (40 cases) and a control group (40 cases) randomly. The study group adopted a treatment method of NMES combined with early rehabilitation and the control group adopted the method of early rehabilitation only. The diaphragmatic excursion (DE), diaphragmatic thickening fraction (DTF), variation of thickness of intercostal muscles (TIM), variation of thickness of rectus abdominis (TRA), and variation of the cross-sectional area of rectus femoris (CSA-RF) were measured to evaluate the therapeutic effect by ultrasound before and after intervention at the first day of MV, the 3rd and 7th day of intervention and the day discharged from ICU.

RESULTS

No significant difference was found in the general demographic information and ultrasound indicators between the two groups before treatment (all P > 0.05). After treatment, the variation of DTF (0.15 ± 0.05% vs. 0.12 ± 0.04%, P = 0.034) was significantly higher in the study group than that in the control group on the day discharged from ICU. The variation of TRA (0.05 ± 0.09% vs. 0.10 ± 0.11%, P = 0.029) and variation of CSA-RF (0.13 ± 0.07% vs. 0.19 ± 0.08%, P < 0.001) in the study group were significantly lower than that in the control group. The duration of MV in the study group was significantly shorter than that in the control group [109.5 (88.0, 213.0) hours vs. 189.5 (131.5, 343.5) hours, P = 0.023]. The study group had better muscle strength score than the control group at discharge (52.20 ± 11.70 vs. 44.10 ± 15.70, P = 0.011).

CONCLUSION

NMES combined with early rehabilitation therapy is beneficial in reducing muscle atrophy and improving muscle strength in mechanically ventilated patients. This treatment approach may provide a new option for patients to choose a rehabilitation program; however, more research is needed to fully evaluate the effectiveness of this treatment option.

Graft-Specific Surgical and Rehabilitation Considerations for Anterior Cruciate Ligament Reconstruction with the Quadriceps Tendon Autograft

Anterior cruciate ligament reconstruction (ACLR) with a bone-patellar tendon-bone (BPTB) or hamstring tendon (HT) autograft has traditionally been the preferred surgical treatment for patients returning to Level 1 sports. More recently, international utilization of the quadriceps tendon (QT) autograft for primary and revision ACLR has increased in popularity. Recent literature suggests that ACLR with the QT may yield less donor site morbidity than the BPTB and better patient-reported outcomes than the HT. Additionally, anatomic and biomechanical studies have highlighted the robust properties of the QT itself, with superior levels of collagen density, length, size, and load-to-failure strength compared to the BPTB. Although previous literature has described rehabilitation considerations for the BPTB and HT autografts, there is less published with respect to the QT. Given the known impact of the various ACLR surgical techniques on postoperative rehabilitation, the purpose of this clinical commentary is to present the procedure-specific surgical and rehabilitation considerations for ACLR with the QT, as well as further highlight the need for procedure-specific rehabilitation strategies after ACLR by comparing the QT to the BPTB and HT autografts.

Level of Evidence

Level 5.

Evidence Review for Preventing Osteoarthritis After an Anterior Cruciate Ligament Injury: An Osteoarthritis Action Alliance Consensus Statement

CONTEXT

The Osteoarthritis Action Alliance formed a secondary prevention task group to develop a consensus on secondary prevention recommendations to reduce the risk of osteoarthritis after a knee injury.

OBJECTIVE

Our goal was to provide clinicians with secondary prevention recommendations that are intended to reduce the risk of osteoarthritis after a person has sustained an anterior cruciate ligament injury. Specifically, this manuscript describes our methods, literature reviews, and dissenting opinions to elaborate on the rationale for our recommendations and to identify critical gaps.

DESIGN

Consensus process.

SETTING

Virtual video conference calls and online voting.

PATIENTS OR OTHER PARTICIPANTS

The Secondary Prevention Task Group consisted of 29 members from various clinical backgrounds.

MAIN OUTCOME MEASURE(S)

The group initially convened online in August 2020 to discuss the target population, goals, and key topics. After a second call, the task group divided into 9 subgroups to draft the recommendations and supportive text for crucial content areas. Twenty-one members completed 2 rounds of voting and revising the recommendations and supportive text between February and April 2021. A virtual meeting was held to review the wording of the recommendations and obtain final votes. We defined consensus as >80% of voting members supporting a proposed recommendation.

RESULTS

The group achieved consensus on 15 of 16 recommendations. The recommendations address patient education, exercise and rehabilitation, psychological skills training, graded-exposure therapy, cognitive-behavioral counseling (lacked consensus), outcomes to monitor, secondary injury prevention, system-level social support, leveraging technology, and coordinated care models.

CONCLUSIONS

This consensus statement reflects information synthesized from an interdisciplinary group of experts based on the best available evidence from the literature or personal experience. We hope this document raises awareness among clinicians and researchers to take steps to mitigate the risk of osteoarthritis after an anterior cruciate ligament injury.

There Is Substantial Variation in Rehabilitation Protocols Following Anterior Cruciate Ligament Reconstruction: A Survey of 46 American Orthopaedic Surgeons

PURPOSE

To identify the clinical practice preferences of orthopaedic surgeons regarding anterior cruciate ligament reconstruction (ACLR) rehabilitation through a survey of members of the Arthroscopy Association of North American (AANA) and the American Orthopaedic Society for Sports Medicine (AOSSM).

METHODS

An online survey was distributed to members of AANA and AOSSM between November 2020 and September 2021. Participants reported on their clinical preferences for ACLR protocol development and patient selection, use of technology in ACLR recovery and rehabilitation, and preferences for advancing through multiple phases of the rehabilitative process.

RESULTS

Responses from 46 orthopaedic surgeons were analyzed. Patient-reported outcome measures were not found to be utilized often at various phases of the perioperative period. Thirty-eight (82.6%) participants reported utilization of postoperative bracing. There was no consensus on when participants allow their patients to advance through rehabilitation, but most report waiting 3 to 4 months for advancement to jogging/lateral movement, 6 to 8 months for return to noncontact sport, and 9 months of more for return to unrestricted sport. Many participants utilize functional and strength testing with associated limb symmetry indices to determine patient readiness to return to sport, with 18, 26, and 25 participants reporting use of functional testing and 28, 26, and 27 participants reporting use of strength testing at the return to jogging/lateral movements, noncontact return to sport, and unrestricted return-to-sport phases, respectively.

CONCLUSIONS

This study provides an insight into the rehabilitative protocols and modalities utilized for ACLR by orthopaedic surgeons in practice across the United States. There is notably substantial variation in rehabilitative patterns and preferences, particularly with regards to what constitutes criteria for progressing patients through the phases of returning to unrestricted sport. Additionally, our findings show that while many surgeons believe that quantitative assessment technology could be beneficial in decision-making for returning patients to sport, there are still many barriers that stand in the way of its implementation into clinical practice.

CLINICAL RELEVANCE

Postoperative rehabilitative protocols after ACLR vary by surgeon.

Motor point heatmap of the calf

BACKGROUND

Contractions of muscles in the calf induced by neuromuscular electrical stimulation (NMES) may prevent venous thromboembolism, help rehabilitation and optimize strength training, among other uses. However, compliance to NMES-treatment is limited by the use of suboptimal stimulation points which may cause discomfort and less effectivity. Knowledge of where one is most likely to find muscle motor points (MP) could improve NMES comfort and compliance.

AIMS

To anatomically map the MPs of the calf as well as to calculate the probability of finding a MP in different areas of the calf.

MATERIAL AND METHODS

On 30 healthy participants (mean age 37 years) anatomical landmarks on the lower limbs were defined. The location of the four most responsive MPs on respectively the medial and lateral head of gastrocnemius were determined in relation to these anatomical landmarks using a MP search pen and a pre-set MP search program with 3 Hz continuous stimulation (Search range:4.0-17.5 mA). The anatomy of the calves was normalized and subdivided into a matrix of 48 (6 × 8) smaller areas (3 × 3 cm), from upper medial to lower lateral, in order to calculate the probability of finding a MP in one of these areas. The probability of finding a MP was then calculated for each area and presented with a 95% confidence interval.

RESULTS

The MP heatmap displayed a higher concentration of MPs proximally and centrally on the calf. However, there were wide inter-individual differences in the location of the MPs. The highest probability of finding a MP was in area 4, located centrally and medially, and in area 29, located centrolaterally and around the maximum circumference, both with 50% probability (95% CI: 0.31-0.69). The second highest probability of finding MPs was in areas 9, 10, 16, proximally and medially, all with 47% probability (95% CI: 0.28-0.66). These areas 4, 9, 10, 16 and 29 exhibited significantly higher probability of finding motor points than all areas with a mean probability of 27% and lower (p < 0.05) The lateral and distal outskirts exhibited almost zero probability of finding MPs.

CONCLUSIONS

This MP heatmap of the calf could be used to expedite electrode placement and to improve compliance in order to receive consistent and enhanced results of NMES treatments.

Study protocol for neuromuscular stimulation for rehabilitation after general and vascular surgery: a pilot randomised clinical study

OBJECTIVES

To investigate the acceptability and safety of neuromuscular stimulation (NMES) as an adjunct for rehabilitation after vascular and general surgery.

METHODS AND ANALYSIS

Prospective, single-centre, single-blind, parallel group, randomised controlled study. This study will be conducted in a single-centre, secondary care setting (National Healthcare Service Hospital) in the UK. All patients aged over 18 years undergoing vascular or general surgery with Rockwood Frailty Score of 3 or above on admission. Exclusion is inability or unwillingness to participate in trial, implanted electrical device, pregnancy and acute deep vein thrombosis. Target number of recruitment is 100. Participants will be randomly assigned to active NMES group (group A) or placebo NMES group (group B) prior to surgery. Participants will be blinded and asked to use the NMES device, 1-6 sessions daily (30 min per session) after surgery in addition to standard National Health Service rehabilitation care until discharge. The primary study outcomes are acceptability and safety of NMES assessed by the device satisfaction questionnaire on discharge and adverse events recorded during hospital stay. The secondary outcomes are the postoperative recovery and cost-effectiveness compared between two groups, assessed by various activity tests, mobility and independence measures and questionnaires.

ETHICS AND DISSEMINATION

Ethical approvals were provided by London-Harrow Research Ethics Committee (REC) and the Health Research Authority (HRA), Ref: 21/PR/0250. Findings will be published in a peer-reviewed journal and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT04784962.

Electromyostimulation in sport

Electromyostimulation (EMS) is a widely used therapeutic tool of low-frequency electrotherapy in several areas of rehabilitation, with gradual use increasingly in sports as well. The main goal of our article is to approach the use of EMS in sports based on available studies. EMS can be called as a training method used to obtain muscle activation through externally applied electric currents to the muscles to achieve a functional increase in sports performance by training fast motor units. Even if, based on the available study database, there are no clear conclusions regarding the effectiveness and application of EMS in the sense of sports, we can say that EMS represents one of the means by which we can influence muscle functionality, not only in terms of rehabilitation, but also as a possible way of increasing sports performance.

Comparable Recovery and Compensatory Strategies in Heel-Rise Performance After a Surgically Repaired Acute Achilles Tendon Rupture: An In Vivo Kinematic Analysis Comparing Early Functional Mobilization and Standard Treatment

BACKGROUND

Deficits in calf muscle function and heel-rise performance are common after an Achilles tendon rupture (ATR) and are related to tendon elongation and calf muscle atrophy. Whether early functional mobilization (EFM) can improve calf muscle function compared with standard treatment (ST) with 2 weeks of immobilization and unloading in a plaster cast is unknown.

HYPOTHESIS

EFM would lead to superior recovery of heel-rise performance, as demonstrated by more symmetrical side-to-side ankle and knee joint kinematics, compared with ST.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

In total, 47 patients with an ATR were prospectively included and treated with open surgical repair and randomized 2:1 postoperatively to either EFM or ST. Overall, 29 patients were treated with a dynamic orthosis (EFM), and 18 underwent ST. At 8 weeks and 6 months after ATR repair, 3-dimensional motion analysis of heel-rise performance was conducted. At 6 months, tendon length and muscle volume were assessed with ultrasound imaging, calf muscle function with the heel-rise test, and patient-reported outcomes with the Achilles tendon Total Rupture Score.

RESULTS

At 8 weeks and 6 months, there were no significant group differences between the EFM and ST groups in heel-rise performance, but significant side-to-side differences in ankle and knee kinematics were detected. At 8 weeks and 6 months, both the EFM and ST groups showed a significantly decreased peak ankle plantarflexion angle and increased knee flexion angle on the injured limb compared with the uninjured limb during bilateral heel raises. Linear regression demonstrated that greater atrophy of the medial gastrocnemius muscle (P = .008) and higher body weight (P < .001) were predictors of a decreased maximum peak ankle plantarflexion angle on the injured limb at 6 months.

CONCLUSION

EFM after an ATR repair did not lead to superior recovery of calf muscle function, as assessed by heel-rise performance, compared with ST. Increased knee flexion seemed to be a compensatory strategy for decreased ankle plantarflexion. Medial gastrocnemius atrophy and increased body weight were additional factors associated with a decreased ankle plantarflexion angle.

REGISTRATION

NCT02318472 (ClinicalTrials.gov identifier).

Isokinetic strengthening and neuromuscular electrical stimulation protocol impact on physical performances, functional status and quality of life in knee osteoarthritis overweight/obese women

BACKGROUND

Knee muscle weakness associated with overweight/obesity can lead to impairment of vital daily function in knee osteoarthritis patients. This study investigated the effect of a knee eccentric isokinetic muscle strength (IMS) training program combined with neuromuscular electrical stimulation (NMES) on muscle strength and flexibility, joint ROM, functional status, physical performance, and quality of life in knee osteoarthritis overweight/obese women.

METHODS

Thirty-six women were randomized into three groups, two experimental groups (EG) and a control group following a classic rehabilitation program. During 6 weeks of two sessions/week, one of the two EGs performed an IMS program (ISO.G); the other underwent combined IMS and NMES training (ISO + NMES.G). All patients were evaluated with clinical examination, isokinetic test at 60°/s and 240°/s speeds, physical performance tests related to activities of daily living, and Knee injury and Osteoarthritis Outcome Score (KOOS) quality of life questionnaire, before and after the intervention.

RESULTS

In the 10-m walk, chair stand, stair climb and monopodal stance tests, muscle flexibility and quality of life scores showed significant improvement for ISO.G (P = 0.000) and ISO + NMES.G (P = 0.000). Concentric strength at 240°/s was improved in ISO + NMES.G (P = 0.000) unlike the muscle strength at 60°/s (quadriceps, P = 0.104; hamstrings, P = 0.171), force asymmetry (P = 0.481) and post-intervention joint ROM (P = 0.309).

CONCLUSIONS

The combination of IMS and NMES shows significant superiority over the usual rehabilitation program for the majority of the parameters measured for optimal management of knee osteoarthritis.

Effects of Neuromuscular Electrical Stimulation and Blood Flow Restriction in Rehabilitation after Anterior Cruciate Ligament Reconstruction

The present study aimed to examine and compare the effects of a rehabilitation exercise (RE) using neuromuscular electrical stimulation (NMES) and blood flow restriction (BFR) on muscle function and knee functional abilities in patients who underwent anterior cruciate ligament reconstruction (ACLR). A total of 45 patients who underwent ACLR (28.76 ± 0.8 years; 34 males and 11 females) were retrospectively divided into three groups: control (CON, n = 15), NMES (n = 15), and BFR (n = 15). All participants carried out the RE program for 60 min, thrice a week for 12 weeks. The Lysholm score, International Knee Documentation Committee (IKDC) subjective score, thigh circumference at 5 cm from the knee joint, Y-balance posterior medial, and lateral significantly increased in all groups via intervention (p < 0.05). However, NMES showed a higher thigh circumference at 15 cm from the knee joint than CON via intervention (p < 0.05), and the strength and endurance of quadriceps femoris and hamstrings and Y-balance anterior showed a significant increase via intervention in NMES and BFR compared with CON (p < 0.05). In conclusion, we confirmed that RE using NMES and BFR effectively enhances muscle function and balance in ACLR patients.

The Influence of Surgical Realignment Procedures on Dynamic Patellar Tracking: A Dynamic Magnetic Resonance Imaging-Controlled Feasibility Study

Persisting patellar maltracking following surgical realignment often remains unseen. The aim of this study was to analyze the effects of realignment procedures on patellofemoral kinematics in patients with patellofemoral instability (PFI) and patellofemoral maltracking (PM) by using dynamic magnetic resonance imaging (MRI). Patients planned for surgical patellar realignment due to PFI and a clinically and radiologically apparent PM between December 2019 and May 2022 were included. Patients without PM, limited range of motion, joint effusion, or concomitant injuries were excluded. Dynamic mediolateral translation (dMPT) and patella tilt (dPT) were measured preoperatively and three months postoperatively. In 24 patients (7 men, 17 women; mean age 23.0 years), 10 tibial tubercle transfers, 5 soft tissue patella tendon transfers, 6 trochleoplasties, 3 lateral lengthenings, 1 varizating distal femoral osteotomy (DFO), and 1 torsional DFO were performed. At final follow-up, dMPT (from 10.95 ± 5.93 mm to 4.89 ± 0.40 mm, p < 0.001) and dPT (from 14.50° ± 10.33° to 8.44° ± 7.46°, p = 0.026) were significantly improved. All static radiological parameters were corrected to physiological values. Surgical patellar realignment contributed to the significant improvement of patellofemoral kinematics, with an approximation to normal values. The postoperative application of dynamic MRI allowed for a quantification of the performed correction, allowing for a postoperative control of success.

Factors Influencing Treatment Outcome and Proprioception after Electrocoagulation of the Femoral Insertion of the Anterior Cruciate Ligament

(1) Background: Studies have established that exercises shaping the sense of deep sensation are an important element of medical rehabilitation of patients after vaporization of the femoral insertion of the anterior cruciate ligament and affect the restoration of correct movement patterns, thus reducing the risk of injuries. The aim of this study was to determine the factors influencing the treatment outcome and deep-feeling function after applying a specific rehabilitation scheme 12 weeks after anterior cruciate ligament electrocoagulation surgery. (2) Methods: The study group consisted of 41 patients after partial rupture of the anterior cruciate ligament, who underwent electrocoagulation of the femoral cruciate ligament attachment and microfracture of the femoral attachment area. All patients were operated on by the same surgeon and then rehabilitated according to the same medical rehabilitation protocol. The anthropometric and clinical data were collected through an anterior drawer test, Lachman test, assessment of the range of movements in the knee joint, muscle strength test, Unterberger test and Lysholm questionnaire. The assessment was performed before the surgery, and then on days 7-10, after 6 and 12 weeks of rehabilitation treatment. (3) Results: Statistical improvement of the parameters was demonstrated by strength of the quadriceps and hamstrings muscle, the Unterberger test, and the Lysholm scale after surgery. A negative correlation was found between the Unterberger test and Lysholm scale at the end of the research period and it differed depending on the gender and the dominant limb. The Lysholm scale and muscle strength were independent of sex, dominant extremity and associated damage of the meniscus and cartilage. The Lysholm scale 6 weeks after surgery negatively correlated with BMI. (4) Conclusions: Stability of the knee joint and improvement of proprioception were demonstrated 12 weeks after treatment with an ACL electrocoagulation and rehabilitation regimen. The factors contributing to a better treatment outcome were greater muscle strength, less thigh asymmetry, better sense of depth, younger age and lower body weight.

A Novel Mobile App-based Neuromuscular Electrical Stimulation Therapy for the Management of Knee Osteoarthritis: Results From an Extension Study of a Randomized, Double-blind, Sham-controlled, Multicenter Trial

Mobile app-based neuromuscular electrical stimulation (NMES) is a promising treatment of knee osteoarthritis as previously demonstrated in a 12-week, randomized, double-blind, sham-controlled, multicenter trial (parent study).

Return to sports after ACL injury 5 years from now: 10 things we must do

Background

The outcome after ACL reconstruction (ACLR) is in general disappointing with unacceptable number of athletes that do not return to pre-injury level of sports, high re-injury rates, early development of osteoarthritis and shorter careers. Athletes after ACLR have high expectation to return to sports which is in contrast with the current outcomes. The aim of this manuscript is to present an overview of factors that are needed to be incorporated and to personalize the rehabilitation process for an athlete who has undergone an ACLR.

Level of evidence

4.

Rehabilitation after anterior cruciate ligament and meniscal injuries: a best-evidence synthesis of systematic reviews for the OPTIKNEE consensus

OBJECTIVE

Synthesise evidence for effectiveness of rehabilitation interventions following ACL and/or meniscal tear on symptomatic, functional, clinical, psychosocial, quality of life and reinjury outcomes.

DESIGN

Overview of systematic reviews with Grading of Recommendations Assessment, Development and Evaluation certainty of evidence.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, SPORTDiscus and Cochrane Library.

ELIGIBILITY CRITERIA

Systematic reviews of randomised controlled trials investigating rehabilitation interventions following ACL and/or meniscal tears in young adults.

RESULTS

We included 22 systematic reviews (142 trials of mostly men) evaluating ACL-injured individuals and none evaluating isolated meniscal injuries. We synthesised data from 16 reviews evaluating 12 different interventions. Moderate-certainty evidence was observed for: (1) neuromuscular electrical stimulation to improve quadriceps strength; (2) open versus closed kinetic chain exercises to be similarly effective for quadriceps strength and self-reported function; (3) structured home-based versus structured in-person rehabilitation to be similarly effective for quadriceps and hamstring strength and self-reported function; and (4) postoperative knee bracing being ineffective for physical function and laxity. There was low-certainty evidence that: (1) preoperative exercise therapy improves self-reported and physical function postoperatively; (2) cryotherapy reduces pain and analgesic use; (3) psychological interventions improve anxiety/fear; and (4) whole body vibration improves quadriceps strength. There was very low-certainty evidence that: (1) protein-based supplements improve quadriceps size; (2) blood flow restriction training improves quadriceps size; (3) neuromuscular control exercises improve quadriceps and hamstring strength and self-reported function; and (4) continuous passive motion has no effect on range of motion.

CONCLUSION

The general level of evidence for rehabilitation after ACL or meniscal tear was low. Moderate-certainty evidence indicates that several rehabilitation types can improve quadriceps strength, while brace use has no effect on knee function/laxity.

A Novel Mobile App-Based Neuromuscular Electrical Stimulation Therapy for Improvement of Knee Pain, Stiffness, and Function in Knee Osteoarthritis: A Randomized Trial

Background

Knee osteoarthritis (OA) is a widespread and debilitating disease that continues to plague patients. Over the past decade, neuromuscular electrical stimulation (NMES) therapy has shown promise in alleviating knee OA-related symptoms. This study sought to evaluate the efficacy and safety of a home-based NMES therapy for reduction of pain, stiffness, and function associated with knee OA.

Material and methods

A randomized, sham-controlled, double-blind, multicenter trial was conducted with 12-week follow-up in 156 knee OA patients receiving either home-based NMES therapy or a modified low-voltage NMES therapy. Outcome measures including knee pain, stiffness, and functionality were collected at baseline through week 12 after the therapy. The primary endpoint was the percentage change from baseline (PCFB) in the Visual Analog Scale (VAS) pain for a patient-nominated physical activity. Secondary endpoints included VAS for general knee pain, Western Ontario and McMaster Universities Osteoarthritis Index, Knee Injury and Osteoarthritis Outcome Score Joint Replacement, and isometric quadriceps strength test.

Results

A clinically meaningful reduction for VAS Nominated Activity was higher in the per-protocol treatment-compliant NMES group than that in the sham low-voltage NMES group at week 12 (PCFB of 42.8% vs 38.6%, P = .562). This was similarly true for the Western Ontario and McMaster Universities Osteoarthritis Index pain subscale (PCFBs of 36.8% vs 26.6%, P = .038). Similar trends and reductions of pain were observed for VAS General, Knee Injury and Osteoarthritis Outcome Score Joint Replacement Pain subscale, and isometric quadriceps strength.

Conclusion

Home-based NMES treatment resulted in a clinically meaningful reduction of knee pain, stiffness, and knee functional improvements at week 12 compared with sham NMES treatment.

Lateral Patellar Dislocation: A Critical Review and Update of Evidence-Based Rehabilitation Practice Guidelines and Expected Outcomes

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Nonoperative treatment of a lateral patellar dislocation produces favorable functional results, but as high as 35% of individuals experience recurrent dislocations.

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Medial patellofemoral ligament reconstruction is an effective treatment to prevent recurrent dislocations and yield excellent outcomes with a high rate of return to sport.

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Both nonoperative and postoperative rehabilitation should center on resolving pain and edema, restoring motion, and incorporating isolated and multijoint progressive strengthening exercises targeting the hip and knee.

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Prior to return to sports, both functional and isolated knee strength measurements should be used to determine leg symmetry strength and to utilize patient-reported outcome measures to assess the patient's perceived physical abilities and patellofemoral joint stability.

Anterior Cruciate Ligament Reconstruction Recovery and Rehabilitation: A Systematic Review

BACKGROUND

The success of anterior cruciate ligament (ACL) reconstruction is influenced by effective rehabilitation. Previously published, comprehensive systematic reviews evaluating rehabilitation after ACL reconstruction have studied Level-I and II evidence published through 2012. Interval studies continue to evaluate the efficacy of various rehabilitative modalities.

METHODS

A total of 824 articles from 2012 to 2020 were identified using multiple search engines. Fifty Level-I or II studies met inclusion criteria and were evaluated using the Consolidated Standards of Reporting Trials (CONSORT) criteria and National Institutes of Health (NIH) Study Quality Assessment Tools.

RESULTS

Accelerated rehabilitation can be effective for patients with semitendinosus-gracilis grafts. Blood flow restriction (BFR) training with high-intensity exercise is not effective for ACL reconstruction recovery. Postoperative bracing does not offer any advantages or improve limb asymmetry. Cryotherapy is an effective analgesic when used perioperatively. The early introduction of open kinetic chain exercises may improve ACL reconstruction outcomes, and high-intensity plyometric exercise is not effective. Estimated pre-injury capacity (EPIC) levels may be more accurate than the Limb Symmetry Index (LSI) when using functional test results to predict reinjury rates, and hip external rotation strength may be the most accurate predictor of the hop test performance. Nerve blocks can provide postoperative analgesia with minimal complication risk. Neuromuscular electrical stimulation is effective when used independently and in combination with rehabilitative exercises. Psychological readiness should be evaluated both objectively and subjectively before allowing patients to safely return to sport. Electromyography biofeedback may help to regain muscular function, and whole-body vibration therapy can improve postural control. Supervised rehabilitation is more effective than unsupervised rehabilitation.

CONCLUSIONS

Various rehabilitative modalities following ACL reconstruction are effective in improving surgical outcomes and return-to-sport rates. Further evidence and improved study design are needed to further validate modalities including accelerated rehabilitation, BFR training, functional testing, and return-to-sport criteria.

LEVEL OF EVIDENCE

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

Arthrogenic Muscle Inhibition Following Anterior Cruciate Ligament Injury

Arthrogenic muscle inhibition (AMI) is a common impairment in individuals who sustain an anterior cruciate ligament (ACL) injury. The AMI causes decreased muscle activation, which impairs muscle strength, leading to aberrant movement biomechanics. The AMI is often resistant to traditional rehabilitation techniques, which leads to persistent neuromuscular deficits following ACL reconstruction. To better treat AMI following ACL injury and ACL reconstruction, it is important to understand the specific neural pathways involved in AMI pathogenesis, as well as the changes in muscle function that may impact movement biomechanics and long-term structural alterations to joint tissue. Overall, AMI is a critical factor that limits optimal rehabilitation outcomes following ACL injury and ACL reconstruction. This review discusses the current understanding of the: (1) neural pathways involved in the AMI pathogenesis following ACL injury; (2) consequence of AMI on muscle function, joint biomechanics, and patient function; and (3) development of posttraumatic osteoarthritis. Finally, the authors review the evidence for interventions specifically used to target AMI following ACL injury.

Acute Effects of 3 Neuromuscular Electrical Stimulation Waveforms on Exercising and Recovery Microvascular Oxygenation Responses

CONTEXT

When emphasizing muscular strength during postoperative rehabilitation it is recommended to use a neuromuscular electrical stimulation (NMES) waveform that elicits the greatest muscle force and local metabolic demand that is also well tolerated. The present investigation examined the effects that 3 different clinically used NMES waveforms had on the electrically elicited force (EEF), local metabolic demand (exercising muscle oxygen saturation [SmO2]), and the subsequent reactive hyperemia response (recovery total hemoglobin concentration [THb]) of the knee extensors.

DESIGN

Single session repeated-measures design.

METHODS

EEF, local metabolic demand, and reactive hyperemia responses were measured during and subsequent to 3 NMES waveforms: Russian burst modulated alternating current (RUS), biphasic pulsed current (VMS™), and burst modulated biphasic pulsed current (VMS-Burst™). Exercising SmO2 and recovery THb were assessed noninvasively using a near-infrared spectroscopy sensor placed on the vastus lateralis. Participants completed one set of 10 repetitions of each NMES waveform and were provided with 5 minutes of passive, interset recovery. Two-way, repeated-measures analysis of variance examined if NMES waveform or repetition significantly affected (P < .05) EEF or exercising SmO2. Two-way, repeated-measures analysis of variance examined if NMES waveform or recovery time affected recovery THb.

RESULTS

VMS™ and VMS-Burst™ yielded higher EEF (F = 11.839, P < .001) and greater local metabolic stress (lower exercising SmO2, F = 13.654, P < .001) compared with RUS. Greater rate of EEF decline throughout the NMES set was observed during RUS (%Δ = -50 [6] %Rep1) compared with VMS-Burst™ (%Δ = -30 [7] %Rep1) and VMS™ (%Δ = -32 [7] %Rep1). VMS™ elicited a higher reactive hyperemia response (higher recovery THb) compared with RUS (F = 3.427, P = .048).

CONCLUSIONS

The present findings support the use of VMS™ or VMS-Burst™ compared with RUS when promoting muscular strength. In addition, the use of VMS™ might provide a greater blood volume to the target muscle subsequent to NMES contractions compared with RUS.

Contemporary Principles for Postoperative Rehabilitation and Return to Sport for Athletes Undergoing Anterior Cruciate Ligament Reconstruction

Despite advancements in our understanding of anterior cruciate ligament (ACL) injury prevention and nonsurgical management, ACL reconstruction continues to occur at an alarming rate. Among athletic patients, individuals participating in basketball, soccer, and football have the highest incidence of ACL injury, often requiring surgical intervention. To ensure the optimal treatment strategy for return to sport and prevention of secondary graft re-tear, it is important to tailor to the specific demands of the injured athlete and apply evidence-based best practices and rehabilitation principles. The purpose of this review is to provide readers with a brief background regarding ACL injuries, a focused review of clinical outcome studies after ACL reconstruction, and an updated framework with expert-guided recommendations for postoperative rehabilitation and return to sporting activity. Currently, there is no gold standard for rehabilitation after ACL reconstruction, highlighting the need for robust studies evaluating the best modalities for athlete rehabilitation, as well as determining the efficacy of new tools for improving therapy including blood flow restriction therapy and neuromuscular electrical stimulation. Based on clinical experience, a renewed focus on objective, criteria-based milestones may maximize the ability of return to preinjury levels of athletic function.

Effect of Neuromuscular Electrical Stimulation After Total Knee Arthroplasty: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: This systematic review and meta-analysis aimed to evaluate the effect of neuromuscular electrical stimulation (NMES) on quadriceps muscle strength, pain, and function outcomes following total knee arthroplasty (TKA).

Methods: PubMed/Medline, Embase, Web of Science, CENTRAL, Scopus, PsycINFO, PEDro, CINAHL, CNKI, and Wanfang were systematically searched for randomized controlled trials (RCTs) from their inception to 18 June 2021.

Results: Nine RCTs that involving 691 patients were included in the meta-analysis. Our pooled analysis showed that NMES improved quadriceps muscle strength after TKA within 1 months [standardized mean difference (SMD): 0.81; 95% CI: 0.51–1.11], 1–2 months (SMD: 0.55; 95% CI: 0.13–0.97), 3–4 months (SMD: 0.42; 95% CI: 0.18–0.66), and 12–13 months (SMD: 0.46; 95% CI: 0.18–0.74), pain between 1 and 2 months [mean difference (MD): −0.62; 95% CI: −1.04 to −0.19], pain between 3 and 6 months (MD: −0.44; 95% CI: −0.74 to −0.14) Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) between 3 and 4 months (MD: −0.43; 95% CI: −0.82 to −0.05), timed up and go test (TUG) within 1 month (MD: −2.23; 95% CI: −3.40 to −1.07), 3 minutes walk test between 3 and 6 months (MD: 28.35; 95% CI: 14.55–42.15), and SF-36 MCS between 3 and 6 months after TKA (MD: 4.20, 95% CI: 2.41–5.98).

Conclusion: As a supplementary treatment after TKA, postoperative NMES could improve the short-term to long-term quadriceps muscle strength, mid-term pain, and mid-term function following TKA. However, many outcomes failed to achieve statistically meaningful changes and minimal clinically important difference (MCID), thus the clinical benefits remained to be confirmed.

Level of Evidence: Therapeutic level I.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42021265609.

The effectiveness of preoperative exercise programmes on quadriceps strength prior to and following anterior cruciate ligament (ACL) reconstruction: A systematic review

OBJECTIVES

to evaluate the effectiveness of preoperative exercise programmes on quadriceps strength prior to and following anterior cruciate ligament (ACL) reconstruction.

DESIGN

Systematic review.

METHODS

a systematic review was undertaken, included studies were evaluated using the Modified Downs and Black checklist which is appropriate for determining the quality of randomised and non-randomised studies. Scientific databases searched included PubMED, EBSCO Health, CINAHL, Medline, and Cochrane Library databases from inception to March 2021.

RESULTS

Ten studies met the inclusion criteria. There were six randomised studies and four prospective studies. The level of evidence is categorised as 'limited' due to heterogenicity and only six studies reported quadriceps strength increases. Five studies demonstrated preoperative exercise of 4-16 weeks duration can significantly increase preoperative quadriceps strength. One study demonstrated preoperative OKC exercise produced significantly stronger preoperative quadriceps compared to CKC exercise. One study showed no between group (intervention vs control) quadriceps strength difference pre or 12 weeks postoperatively.

CONCLUSIONS

4-16 weeks of preoperative exercise could increase quadriceps strength preoperatively but any persistent postoperative strength benefit from undertaking a standardised preoperative intervention is unclear. There is considerable variation and methodological limitations across the included studies and the composition of optimal preoperative ACLR exercise is currently unknown.

Neuromuscular electrical stimulation for motor recovery in pediatric neurological conditions: a scoping review

AIM

To explore the breadth of pediatric neurological conditions for which neuromuscular electrical stimulation (NMES) has been studied.

METHOD

Databases (PubMed, Google Scholar, Scopus, and Embase) were searched from 2000 to 2020, using the search terms 'neuromuscular electrical stimulation' OR 'functional electrical stimulation' with at least one of the words 'pediatric OR child OR children OR adolescent', and without the words 'dysphagia OR implanted OR enuresis OR constipation'. Articles focused on adults or individuals with cerebral palsy (CP) were excluded.

RESULTS

Thirty-five studies met the inclusion criteria, with a total of 353 pediatric participants (293 unique participants; mean age 7y 4mo, range 1wk-38y). NMES was applied in a range of pediatric conditions other than CP, including stroke, spinal cord injury, myelomeningocele, scoliosis, congenital clubfoot, obstetric brachial plexus injury, genetic neuromuscular diseases, and other neuromuscular conditions causing weakness.

INTERPRETATION

All 35 studies concluded that NMES was well-tolerated and most studies suggested that NMES could augment traditional therapy methods to improve strength. Outcome measurements were heterogeneous. Further research on NMES with larger, randomized studies will help clarify its potential to improve physiology and mobility in pediatric patients with neuromuscular conditions. What this paper adds Neuromuscular electrical stimulation (NMES) appears to be tolerated by pediatric patients. NMES shows potential for augmenting recovery in pediatric patients with a range of rehabilitation needs.

Quadriceps muscle strength recovery with the use of high tone power therapy after anterior cruciate ligament reconstruction: a randomized controlled trial

Background

There are no scientific reports clearly describing the effectiveness of the High Tone Power Therapy in patients after ACL reconstruction. This caused that in own research an attempt was made to present the possibilities of using the selected method of electrical stimulation in the treatment of an orthopaedic patient. The aim was to assess the effectiveness of electro stimulation of the quadriceps muscle in patients after ACL reconstruction, with the use of High Tone Power Therapy.

Methods

In randomized controlled trial took part thirty-five men, aged 21–50, after ACL reconstruction. The tests were carried prior to and 6 months following the ACL reconstruction. After the surgery, the patients were randomly divided into experimental group (17 patients) with the High Tone Power Therapy in rehabilitation and control group (18 patients) without the High Tone Power Therapy. Patients were subjected to 6-month rehabilitation. Research tools included the measurement of muscle strength torque, ROM, knee and thigh circumference measurements, the Lysholm and the VAS scale.

Results

After applying HiToP, the analysis showed a statistically significant improvement of muscle torque (p = 0.041, Es = 3.71), knee circumference (p = 0.039, Es = 1.65), thigh circumference (p = 0.049, Es = 1.26), knee extension (p < 0.001, Es = 2.20) in Experimental group compared to the control group. Only the results of the VAS scale did not differ statistically significantly both within a given group and between groups.

Conclusions

The results confirm the hypothesis that the use of HiToP in patients after ACLr have a beneficial effect on muscle strength, reduction of joint effusion, muscle mass gain and joint function. The assumption that HiToP significantly reduces pain levels is not supported - the results in both groups are statistically insignificant.

Trial registration

The research project was retrospectively registered in the Australian New Zealand Clinical Trials Registry (ANZCTR). Date of first registration 11.10.2016. Registration number: ACTRN12616001416482.

THE EFFECTS OF NEUROMUSCULAR ELECTRICAL STIMULATION IN ASSOCIATION WITH WHEY PROTEIN SUPPLEMENTATION AFTER ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

OBJECTIVE

To analyze the effects of neuromuscular electrical stimulation of the femoral quadriceps associated or not with whey protein supplementation on the electromyographic activity and body mass distribution in volunteers undergoing anterior cruciate ligament reconstruction.

METHODS

24 volunteers were randomly divided into three groups: basal control, whey protein in association with neuromuscular electrical stimulation, and neuromuscular electrical stimulation alone.

RESULTS

In the postoperative evaluation, during the mini squat, the basal group showed a decrease in the electromyographic activity of the vastus medialis (p = 0.005, eyes open; p = 0.003, eyes closed), vastus lateralis (p = 0.005, eyes open; p = 0.020; eyes closed) and rectus femoris (p = 0.075, eyes open; p = 0.074, eyes closed) and of body mass distribution in the injured limb (p < 0.001, eyes open; p < 0.001, eyes closed), and in the healthy limb (p < 0.001, eyes open; p < 0.001, eyes closed).

CONCLUSION

The early use of neuromuscular electrical stimulation of the quadriceps femoris maintained the electromyographic activity of the vastus medialis and vastus lateralis muscles and prevented asymmetries in body mass distribution 15 days after anterior cruciate ligament reconstruction. Level of Evidence I, High quality randomized trial.

A systematic review of using electrical stimulation to improve clinical outcomes after hip fractures

BACKGROUND

Pain and muscles weakness often delays regaining independent mobility following hip fracture surgery. Electrical stimulation may relieve pain and improve muscle strength and function.

PURPOSE

To systematically review and evaluate available literature examining the effectiveness of using electrical stimulation to promote clinical outcomes after hip fractures.

METHODS

Two researchers independently searched MEDLINE, CINAHL, EMBASE, Web of Science, Cochrane Reviews, Physiotherapy Evidence Database, and PsycInfo from inception to July 1, 2018, with no restrictions. The quality and fidelity of the included interventions were assessed, and expert consultation was conducted to help explain the results.

RESULTS

We identified 432 records through database searching. Initial screening indicated 24 articles were appropriate for full-text review, and four articles met the inclusion criteria. In included studies, electrical stimulation (i.e. TENS) reduced pain (mean difference (MD) = 3.3 points on 10-point Visual Analogue Scale, p < .001), improved range of motion (ROM) (MD: 25.7°, p < .001), and accelerated functional recovery immediately after hip fracture (p < .001). Conflicting evidence existed when using neuromuscular electrical stimulation to improve muscle strength and other functional outcomes (e.g. mobility); however, nine experts advised that longer-term interventions might be necessary to achieve significant improvment in muscle strength.

CONCLUSION

Available evidence, albeit limited, supports the early application of noninvasive electrical stimulation (e.g. TENS) for improving clinical outcomes (i.e. reducing pain, improving ROM, and accelerating functional recovery after hip fractures). We could not find conclusive evidence on the effectiveness of using electrical stimulation to improve muscle strength. This review establishes the need for future additional high-quality trials in this field.

Assessment of Static Steadiness and Dynamic Stability at Various Stages of Healing of a Grade 2 Medial Collateral Ligament Tear: A Case Report

Injuries to ligaments of the knee are extremely common among athletes who participate in high-risk sports or any sport that requires frequent cutting motions, jumping, or contact. In order to determine the best way to heal these injuries, it is important to understand not just the pathology of the injury but also the biomechanical factors that are affected, including stability and steadiness. While many studies have been conducted to examine the stability of healthy knees, there is little to no existing literature on stability of knees afflicted by injury. In order to surpass this obstacle, static steadiness and dynamic stability data were collected using the Lockhart Monitor phone application and Xsens accelerometers, respectively, both before and after completion of a course of physical therapy in a subject with a grade 2 medial collateral ligament (MCL) tear. These results were then used to determine the degree to which the prescribed physical therapy protocol was effective in healing the MCL, which can be useful for adjusting the individual protocol for future conservative treatment and management of the injury.

Optimising the 'Mid-Stage' Training and Testing Process After ACL Reconstruction

Outcomes following anterior cruciate ligament (ACL) reconstruction need improving, with poor return-to-sport rates and high risk of secondary re-injury. There is a need to improve rehabilitation strategies after ACL reconstruction, if we can support enhanced patient outcomes. This paper discusses how to optimise the mid-stage rehabilitation process after ACL reconstruction. Mid-stage is a difficult and vitally important stage of the functional recovery process and provides the foundation on which to commence late-stage rehabilitation training. Often many aspects of mid-stage rehabilitation (e.g. knee extensors isolated muscle strength) are not actually restored prior to return-to-sport. In addition, if we are to allow time for optimal late-stage rehabilitation and return-to-sport training, we need to optimise the mid-stage rehabilitation approach and complete it in a timely manner. This paper forms a key part of a strategy to optimise the ACL rehabilitation approach and considers factors more specific to mid-stage rehabilitation characterised in 3 areas: (1) muscle strength: muscle and joint specific, in particular at the knee level, with the knee extensors and flexors and distally with the triceps surae and proximally with the lumbo-pelvic-hip complex, as well as closed kinetic chain strength; (2) altered basic motor patterning (movement quality) and (3) fitness re-conditioning. In addition, the paper provides recommendations on how to implement these into practice, discussing training planning and programming and suggests specific screening to monitor work and when the athlete is able to progress to the next stage (e.g. late-stage rehabilitation criteria).

Postoperative Management for Articular Cartilage Surgery in the Knee

The postoperative rehabilitation team plays a crucial role in optimizing outcomes after articular cartilage surgery. A comprehensive approach to postoperative physical therapy that considers the type of surgery, location in the knee, concurrent procedures, and patient-specific factors is imperative. While postoperative rehabilitation protocols should be specific to the patient and type of surgery performed and include phased rehabilitation goals and activities, the key principles for postoperative rehabilitation apply across the spectrum of articular cartilage surgeries and patients. These key principles consist of preoperative assessments that include physical, mental, and behavioral components critical to recovery; education and counseling with respect to expectations and compliance; and careful monitoring and adjustments throughout the rehabilitation period based on consistent communication among rehabilitation, surgical, and imaging teams to ensure strict patient compliance with restrictions, activities, and timelines to optimize functional outcomes after surgery.

Utility of Neuromuscular Electrical Stimulation to Preserve Quadriceps Muscle Fiber Size and Contractility After Anterior Cruciate Ligament Injuries and Reconstruction: A Randomized, Sham-Controlled, Blinded Trial

BACKGROUND

Anterior cruciate ligament (ACL) injuries and reconstruction (ACLR) promote quadriceps muscle atrophy and weakness that can persist for years, suggesting the need for more effective rehabilitation programs. Whether neuromuscular electrical stimulation (NMES) can be used to prevent maladaptations in skeletal muscle size and function is unclear.

PURPOSE

To examine whether early NMES use, started soon after an injury and maintained through 3 weeks after surgery, can preserve quadriceps muscle size and contractile function at the cellular (ie, fiber) level in the injured versus noninjured leg of patients undergoing ACLR.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients (n = 25; 12 men/13 women) with an acute, first-time ACL rupture were randomized to NMES (5 d/wk) or sham (simulated microcurrent electrical nerve stimulation; 5 d/wk) treatment to the quadriceps muscles of their injured leg. Bilateral biopsies of the vastus lateralis were performed 3 weeks after surgery to measure skeletal muscle fiber size and contractility. Quadriceps muscle size and strength were assessed 6 months after surgery.

RESULTS

A total of 21 patients (9 men/12 women) completed the trial. ACLR reduced single muscle fiber size and contractility across all fiber types (P < .01 to P < .001) in the injured compared with noninjured leg 3 weeks after surgery. NMES reduced muscle fiber atrophy (P < .01) through effects on fast-twitch myosin heavy chain (MHC) II fibers (P < .01 to P < .001). NMES preserved contractility in slow-twitch MHC I fibers (P < .01 to P < .001), increasing maximal contractile velocity (P < .01) and preserving power output (P < .01), but not in MHC II fibers. Differences in whole muscle strength between groups were not discerned 6 months after surgery.

CONCLUSION

Early NMES use reduced skeletal muscle fiber atrophy in MHC II fibers and preserved contractility in MHC I fibers. These results provide seminal, cellular-level data demonstrating the utility of the early use of NMES to beneficially modify skeletal muscle maladaptations to ACLR.

CLINICAL RELEVANCE

Our results provide the first comprehensive, cellular-level evidence to show that the early use of NMES mitigates early skeletal muscle maladaptations to ACLR.

REGISTRATION

NCT02945553 (ClinicalTrials.gov identifier).

Skeletal Muscle Disuse Atrophy and the Rehabilitative Role of Protein in Recovery from Musculoskeletal Injury

Muscle atrophy and weakness occur as a consequence of disuse after musculoskeletal injury (MSI). The slow recovery and persistence of these deficits even after physical rehabilitation efforts indicate that interventions designed to attenuate muscle atrophy and protect muscle function are necessary to accelerate and optimize recovery from MSI. Evidence suggests that manipulating protein intake via dietary protein or free amino acid-based supplementation diminishes muscle atrophy and/or preserves muscle function in experimental models of disuse (i.e., immobilization and bed rest in healthy populations). However, this concept has rarely been considered in the context of disuse following MSI, which often occurs with some muscle activation during postinjury physical rehabilitation. Given that exercise sensitizes skeletal muscle to the anabolic effect of protein ingestion, early rehabilitation may act synergistically with dietary protein to protect muscle mass and function during postinjury disuse conditions. This narrative review explores mechanisms of skeletal muscle disuse atrophy and recent advances delineating the role of protein intake as a potential countermeasure. The possible synergistic effect of protein-based interventions and postinjury rehabilitation in attenuating muscle atrophy and weakness following MSI is also considered.

Movement Caused by Electrical Stimulation of the Lumbosacral Region in Standing Horses

Electrical stimulation is commonly used as a modality for physical therapy in human and veterinary medicine. However, studies measuring the movement generated by electrical stimulation in horses are rare. The present study therefore evaluates the range of movement provoked by a commercially available physical therapy unit (FES310) and contrasts it with the movement generated by manually induced pelvic inclination (back rounding). Ten horses were tested on three measurement days over one week. Electrical stimulation was applied via a back treatment pad (belonging to the FES310 system) containing six electrodes (three on either side of the spine) placed over the lumbosacral region. This system produced a pulsed, biphasic electrical stimulation in a rectangular waveform which was gradually increased to a maximum of 10 volts. Before and after electrical stimulation testing, manual pelvic inclination was achieved by pressure on two points lateral to the root of the tail. Muscle tone and lameness were evaluated before and after treatments. Skinfold thickness, body condition score, and body mass were measured to detect possible confounding factors. Using kinematics, the angle ranges during movement of ten three-dimensional angles of the trunk, the pelvis, and the hind limbs were further analyzed. Movement was produced with manual stimulation in every tested individual on all measurement days and with electrical stimulation on at least one measurement day. The electrical stimulation led to significantly (P < .05) smaller angle ranges which were 15 %-57 % of the median of the manually stimulated movement. Strong positive correlations between angle ranges of the electrically generated movement were found for the hind limbs implicating their involvement in the movement created. Correlations between skinfold thickness, body condition score, and body mass with the angle ranges were weak and not significant. Before and after electrical and manual stimulation, muscle tone and lameness were similar. In the present study, both electrical and manual stimulation were proven to produce significant trunk and hind limb movement. Within this study's electrical stimulation treatment protocol, the movement generated by electrical stimulation was significantly less than the movement caused by manual pelvic inclination. However, electrical stimulation could easily be applied over a longer period and in a higher frequency than it would be possible for manual pelvic inclination. This treatment shows potential for stabilization and or mobilization of the lumbosacral region, although its efficiency as a therapeutic tool and its effect on specific orthopedic problems and is to be evaluated in further research.

A Cyber-Physical System for Near Real-Time Monitoring of At-Home Orthopedic Rehabilitation and Mobile-Based Provider-Patient Communications to Improve Adherence: Development and Formative Evaluation

BACKGROUND

Knee extensor muscle performance is reduced after lower extremity trauma and orthopedic surgical interventions. At-home use of neuromuscular electrical stimulation (NMES) may improve functional recovery, but adherence to at-home interventions is low. Greater benefits from NMES may be realized with closer monitoring of adherence to at-home prescriptions and more frequent patient-provider interactions.

OBJECTIVE

This study aimed to develop a cyber-physical system to monitor at-home adherence to NMES prescription and facilitate patient-provider communications to improve adherence in near real time.

METHODS

The RehabTracker cyber-physical system was developed to accomplish this goal and comprises four components: (1) hardware modifications to a commercially available NMES therapy device to monitor device use and provide Bluetooth functionality; (2) an iPhone Operating System-based mobile health (mHealth) app that enables patient-provider communications in near real time; (3) a clinician portal to allow oversight of patient adherence with device use; and (4) a back-end server to store data, enable adherence analysis, and send automated push notifications to the patient. These four elements were designed to be fully compliant with the Health Insurance Portability and Accountability Act. The system underwent formative testing in a cohort of patients following anterior cruciate ligament rupture (n=7) to begin to assess face validity.

RESULTS

Compared with the NMES device software-tracked device use, the RehabTracker system recorded 83% (40/48) of the rehabilitation sessions, with 100% (32/32) of all sessions logged by the system in 4 out of 7 patients. In patients for whom tracking of automated push notifications was enabled, 100% (29/29) of the push notifications sent by the back-end server were received by the patient. Process, hardware, and software issues contributing to these inaccuracies are detailed.

CONCLUSIONS

RehabTracker represents a promising mHealth app for tracking and improving adherence with at-home NMES rehabilitation programs and warrants further refinement and testing.

Hop tests can result in higher limb symmetry index values than isokinetic strength and leg press tests in patients following ACL reconstruction

PURPOSE

Quadriceps weakness is a common clinical sign following anterior cruciate ligament injury and reconstruction surgery (ACLR). The aim of this study was to compare strength deficits and the limb symmetry index (LSI) from three different types of functional tests: isokinetic dynamometry, hop test, and leg press.

METHODS

A total of 26 subjects with ACLR (average 8.3 months post-operation) participated in the study. The peak knee extension torque was tested with isokinetic dynamometry at 60/180/300 °/s (ISO60/180/300). Hop distance was tested during single hop (SH) and triple hop (TH). Unilateral peak leg power (POWER) was tested during a bilateral leg press test. LSI was calculated as the ratio of the involved limb over the uninvolved limb values. Pearson correlation coefficients and paired t-tests were used to establish relationships among ISO60/180/300, SH/TH, and POWER values and compare these values between the limbs, respectively. Within-subject one-way analysis of variance (ANOVA) with post hoc analyses was used to compare LSI values among different tests.

RESULTS

ISO60/180/300 values were significantly positively correlated with SH/TH and POWER (P < 0.05), while SH/TH and POWER values were not significantly correlated. Significant limb differences were found in all tests (P = 0.001-0.008). ANOVA revealed significant LSI differences among different tests. Specifically, post hoc analyses revealed that LSI during SH was significantly higher than LSI during ISO60. Similarly, LSI during TH was significantly higher than LSIs from ISO60, ISO180, and POWER tests.

CONCLUSIONS

Peak knee extension torque values were positively associated with hop distance and leg power during the leg press test. However, LSI values should be interpreted with caution as hop tests provided significantly higher LSI values than isokinetic testing. Both isokinetic dynamometry and unilateral leg press machine could be used to isolate and strengthen the quadriceps in the involved limb. The current "gold standard" isokinetic testing at slow speed (ISO60) provided the lowest LSI value among all functional tests; therefore, the current study supported a continued use of isokinetic testing when examining individual's readiness and return-to-sport.

LEVEL OF EVIDENCE

III.

Influência da reabilitação física sobre aspectos funcionais em indivíduos submetidos à artroplastia total de quadril: uma revisão sistemática

Resumo Objetivo: Avaliar, por meio de revisão sistemática, a influência do tratamento fisioterapêutico sobre a funcionalidade, amplitude de movimento articular e força muscular em pacientes submetidos à artroplastia total de quadril devido à osteoartrite. Métodos: A busca sistemática de ensaios clínicos randomizados e não randomizados foi conduzida utilizando os bancos de dados eletrônicos PubMed, Web of Science, PEDro, Cochrane, Clinical Trials e SciELO, com base nas estratégias de pesquisa recomendadas pelos itens de relatórios preferenciais para análises sistemáticas e metanálises (PRISMA). Resultados: Em geral, protocolos supervisionados por fisioterapeutas associados à realização de exercícios ativos da musculatura periarticular do quadril e de extensores de joelho têm propiciado importante prognóstico físico e funcional. Exercícios resistidos (dinâmicos e isométricos) de alta intensidade são mais eficazes para a funcionalidade. Para a força muscular e Amplitude de movimento (ADM), exercícios dinâmicos com 3 a 5 séries de 8 a 12 repetições com baixa e alta intensidade promoveram ganhos mais expressivos em relação a outras modalidades terapêuticas. Conclusões: As técnicas e os protocolos utilizados pela fisioterapia para o tratamento da ATQ são variados e possuem importante eficácia clínica comprovada na literatura.

PRP and BMAC for Musculoskeletal Conditions via Biomaterial Carriers

Platelet-rich plasma (PRP) and bone marrow aspirate concentrate (BMAC) are orthobiologic therapies considered as an alternative to the current therapies for muscle, bone and cartilage. Different formulations of biomaterials have been used as carriers for PRP and BMAC in order to increase regenerative processes. The most common biomaterials utilized in conjunction with PRP and BMAC clinical trials are organic scaffolds and natural or synthetic polymers. This review will cover the combinatorial strategies of biomaterial carriers with PRP and BMAC for musculoskeletal conditions (MsCs) repair and regeneration in clinical trials. The main objective is to review the therapeutic use of PRP and BMAC as a treatment option for muscle, bone and cartilage injuries.

Functional electrical stimulation following anterior cruciate ligament reconstruction: a randomized controlled pilot study

Background

Inadequate quadriceps strength following anterior cruciate ligament reconstruction (ACLR) often results in alterations in gait pattern that are usually reported during loading response. Neuro-muscular electrical stimulation (NMES) is frequently used to overcome this quadriceps weakness. Despite the beneficial effects of NMES, persistent deficits in strength and gait are reported. The aim of this study was to investigate the feasibility of applying quadriceps functional electrical stimulation (FES) during walking in addition to standard rehabilitation, in the initial stage of ACLR rehabilitation.

Methods

Subjects were randomized to quadriceps FES synchronized with walking group (n = 10) or quadriceps NMES (duty cycle of 10 s on/10 s off) group (n = 13). Both interventions were performed for 10 min three days a week, in addition to a standard rehabilitation program. Assessments were performed up to 2 weeks before the ACLR (pre-ACLR), and 4 weeks postoperatively. Outcomes measured were gait speed, single limb stance gait symmetry, quadriceps isometric peak strength ratio (peak strength at 4 weeks/peak strength pre-ACLR) and peak strength inter-limb symmetry. Gait outcomes were also assessed 1-week post-surgery.

Results

Subjects in both groups regained pre-ACLR gait speed and symmetry after 4 weeks of rehabilitation, with no difference between groups. However, although pre-ACLR quadriceps peak strength was similar between groups (FES - 205 Nm, NMES − 225 Nm, p = 0.605), subjects in the FES group regained 82% of their pre-quadriceps strength compared to 47% in the NMES group (p = 0.02). In addition, after 4 weeks, the FES group had significantly better inter-limb strength symmetry 0.63 ± 0.15 vs. 0.39 ± 0.18 in the NMES group (p = 0.01).

Conclusions

Quadriceps FES combined with traditional rehabilitation is a feasible, early intervention treatment option, post-ACLR. Furthermore, at 4 weeks post-surgery, FES was more effective in recovering quadriceps muscle strength than was NMES. While spatiotemporal gait parameters did not differ between groups, kinetic and kinematic studies may be useful to further understand the effects of quadriceps FES post-ACLR. The promising results of this preliminary investigation suggest that such studies are warranted.

Trial registration

ISRCTN 02817399. First posted June 29, 2016.

Self-Managed Strength Training for Active Duty Military With a Knee Injury: A Randomized Controlled Pilot Trial

INTRODUCTION

Knee injuries among active duty military are one of the most frequent musculoskeletal injuries and are often caused by exercise or intense physical activity or combat training. These injuries pose a threat to force readiness. Our objective was to assess feasibility (including recruitment and retention rates) of three self-managed strengthening strategies for knee injuries and determine if they resulted in improvements in lower extremity strength, function, pain, and activity compared to usual physical therapy (PT) in military members.

METHODS

A pilot study using a randomized controlled trial was conducted at three outpatient military medical treatment facilities. After baseline testing, 78 active duty military members with a knee injury were randomized to 1-4 trial arms: (1) neuromuscular electrical stimulation (NMES) applied to the quadriceps muscle; (2) graduated strength walking using a weighted vest (WALK); (3) combined NMES with strength walking (COMBO); (4) usual PT alone. All groups received usual PT. The primary outcome was the rates of change in knee extensor and flexor strength over 18 weeks. Secondary outcomes explored the rates of change in functional performance, pain, and activities of daily living scale (ADLS). The primary analysis for the endpoints used repeated measures, linear mixed-effects models. This study was approved by Institutional Review Boards at all facilities.

RESULTS

The randomized sample (N = 78) included 19 participants in the PT-only, 20 in the WALK, 19 in the NMES and 20 in the COMBO groups. At baseline, there were no group differences. Fifty of the participants completed the 18-week study. The completers and non-completers differed at baseline on injury mechanism, with more completers injured during sports (45% vs 29%), and more non-completers during military training (36% vs 18%). Also, they differed in uninjured knee extension (completers 28% weaker), and uninjured knee flexion (completers 22% weaker). Adherence for self-reported daily step logs showed that the WALK group was 15% below goal and COMBO group 6% below goal. The 300 PV muscle stimulator showed the NMES group completed 34% of recommended stimulation sessions and the COMBO group 30%.Knee extension strength in the injured knee found only the COMBO group having a statistically higher improvement compared to PT-only (Change over 18 weeks: 10.6 kg in COMBO; 2.1 kg in PT-only). For the injured knee flexion changes, only the COMBO showed significant difference from PT-only (Change over 18 weeks: 7.5 kg in COMBO; -0.2 kg in PT-only). Similarly, for the uninjured knee, only the COMBO showed significant difference from PT-only in knee extension (Change over 18 weeks: 14.7 Kg in COMBO; 2.7 kg in PT-only) and knee flexion (Change over 18 weeks: 6.5 kg in COMBO; -0.2 kg in PT-only). Overall pain improved during the study for all groups with no significant group differences. Similarly, function and ADLS significantly improved over 18 weeks, with no significant group differences.

CONCLUSIONS

Knee extensor strength improvements in the COMBO group were significantly higher compared to usual PT. Pain, functional measures, and ADLS all improved during the study with no group differences. Further research is required to confirm these findings.

An Acute Exposure to Muscle Vibration Decreases Knee Extensors Force Production and Modulates Associated Central Nervous System Excitability

Local vibration (LV) has been recently validated as an efficient training method to improve muscle strength. Understanding the acute effects may help elucidate the mechanism(s). This study aimed to investigate the effects of a single bout of prolonged LV on knee extensor force production and corticospinal responsiveness of vastus lateralis (VL) and rectus femoris (RF) muscles in healthy young and old adults. Across two visits, 23 adult subjects (20-75 years old) performed pre- and post-test measurements, separated by 30-min of either rest (control; CON) or LV. Maximal voluntary contraction (MVC) force was assessed and transcranial magnetic stimulation (TMS) was used to evaluate cortical voluntary activation (VATMS) as well as the motor evoked potential (MEP) and silent period (SP). In 11 young adults, thoracic electrical stimulation was used to assess the thoracic motor evoked potential (TMEP). Although MVC decreased after both CON (-6.3 ± 4.4%, p = 0.01) and LV (-12.9 ± 7.7%, p < 0.001), the MVC loss was greater after LV (p = 0.001). Normalized maximal electromyographic (EMG) activity decreased after LV for both VL (-25.1 ± 10.7%) and RF (-20.9 ± 16.5%; p < 0.001), while it was unchanged after CON (p = 0.32). For RF, the TMEP and MEP/TMEP ratio decreased (p = 0.01) and increased (p = 0.01) after LV, respectively. Both measures were unchanged for VL (p = 0.27 and p = 0.15, respectively). No changes were reported for TMS-related parameters. These results confirm our hypothesis that modulations within the central nervous system would accompany the significant reduction of maximal voluntary force. A reduced motoneuron excitability seems to explain the decreased MVC after prolonged LV, as suggested by reductions in maximal EMG (all subjects) and TMEP area (data from 11 young subjects). A concomitant increased cortical excitability seems to compensate for lower excitability at the spinal level.