Flexion Force Research Articles

Reliability and validity of the finger flexor dynamometer

Introduction Dynamometric measurement is a low-cost, noninvasive method for diagnosing and evaluating traumatic and degenerative disorders. The purpose of this study was to assess the reliability and validity of a new custom-made finger flexor dynamometer and evaluate the feasibility of the measuring procedure. Methods Maximum voluntary isometric contraction force at the distal phalanx of the index finger was measured for 1.5 s in 25 healthy volunteers (18–50 yrs). Test–retest reliability and inter-day reliability were assessed by intraclass correlation coefficient model (2,k) on two and five consecutive days, respectively. Both a single measurement and the mean of three repeated measurements were carried out daily. The standard error of measurement was used to measure the absolute reliability, the smallest detectable change was determined, and the coefficient of variation was calculated for each individual. Construct validity was determined by Pearson coefficient. Results Repeated measurement test–retest reliability was excellent according to Munro’s rating scale, with an intraclass correlation coefficient of 0.99 (95%CI: 0.97–0.99), coefficient of variation of 2.6%, and standard error of measurement of 0.4 N. Single measurement test–retest reliability was high to excellent with an intraclass correlation coefficient of 0.94 (95%CI: 0.86–0.97), coefficient of variation of 4.1%, and standard error of measurement of 1.4 N. Smallest detectable change increased from 1.8 N (repeated measurement) to 3.3 N (single measurement). Inter-day reliability intraclass correlation coefficients exceeded 0.93. High construct validity was indicated by a convergent relationship with grip strength (r = 0.85, p < 0.001). Conclusions The novel dynamometer provides excellent reliability and construct validity and supports an objective diagnosis of finger limitations by quantifying the flexion force magnitude. Traumatic injuries and follow-up of rehabilitative treatment can be monitored more precisely.

An assessment of fatigability following nerve transfer to reinnervate elbow flexor muscles.

Improvements in the evaluation of outcomes following peripheral nerve injury are needed. Recent studies have identified muscle fatigue as an inevitable consequence of muscle reinnervation. This study aimed to quantify and characterize muscle fatigue within a standardized surgical model of muscle reinnervation. This retrospective cohort study included 12 patients who underwent Oberlin nerve transfer in an attempt to restore flexion of the elbow following brachial plexus injury. There were ten men and two women with a mean age of 45.5 years (27 to 69). The mean follow-up was 58 months (28 to 100). Repeated and sustained isometric contractions of the elbow flexors were used to assess fatigability of reinnervated muscle. The strength of elbow flexion was measured using a static dynamometer (KgF) and surface electromyography (sEMG). Recordings were used to quantify and characterize fatigability of the reinnervated elbow flexor muscles compared with the uninjured contralateral side. The mean peak force of elbow flexion was 7.88 KgF (sd 3.80) compared with 20.65 KgF (sd 6.88) on the contralateral side (p < 0.001). Reinnervated elbow flexor muscles (biceps brachialis) showed sEMG evidence of fatigue earlier than normal controls with sustained (60-second) isometric contraction. Reinnervated elbow flexor muscles also showed a trend towards a faster twitch muscle fibre type. The assessment of motor outcomes must involve more than peak force alone. Reinnervated muscle shows a shift towards fast twitch fibres following reinnervation with an earlier onset of fatigue. Our findings suggest that fatigue is a clinically relevant characteristic of reinnervated muscle. Adoption of these metrics into clinical practice and the assessment of outcome could allow a more meaningful comparison to be made between differing forms of treatment and encourage advances in the management of motor recovery following nerve transfer. Cite this article: Bone Joint J 2019;101-B:867-871.

The Effects of Vibration Exercise after Modified Bröstrom Operation in Soccer Players with Ankle Instability

Background: Vibration exercise after ankle surgery improves proprioception and ankle muscle strength through vibration stimulation. Objective: To examine the effects of vibration exercise on the ankle stability. Design: Randomized controlled clinical trial (single blind) Methods: Twenty soccer players were randomly divided into experimental group and control group. The Vibration exercise program was conducted 12 weeks and 3 times a week. Ankle joint proprioceptive sensory test and Isokinetic muscle strength test were performed using Biodex system pro Ⅲ to measure plantar flexion / dorsiflexion and eversion / inversion motion. Results: The result of isokinetic test of ankle joint is showed significant improvement in all measurement items, such as leg flexion, lateral flexion, external and internal muscle forces, compared to previous ones by performing vibration movements for 12 weeks. However, in the comparison group, plantar flexor (30°), eversion muscle (120°), inversion (30°) of limb muscle strength were significantly improvedcompared with the previous phase; was no significant difference in dorsi-flexion. There was no significant difference between groups in all the items. Conclusions: In this study, we analyzed the effects of rehabilitation exercise on soccer players who had reconstructed with an ankle joint ligament injury through vibration exercise device. As a result, we could propose an effective exercise method to improve the ability, and confirmed the applicability as an appropriate exercise program to prevent ankle injuries and help quick return.

Muscle recovery at 1year after the anterior cruciate ligament reconstruction surgery is associated with preoperative and early postoperative muscular strength of the knee extension.

The anterior cruciate ligament (ACL) injury often occurs in young athletes, but it also occurs in middle-aged individuals and the elderly during recreational sports activities. Clinical outcomes after the ACL reconstruction depend on postoperative recovery of muscular strength. The current study aimed to evaluate the recovery of knee extension and flexion strength after ACL reconstruction surgery and to examine the relationship between preoperative and postoperative muscle strength by age and the type of graft used. From 2007 to 2010, 32 patients (17 men, 15 women; average age, 31years; range, 14-66years) who underwent two-bundle ACL reconstruction surgery using hamstrings, i.e., semitendinous and gracilis tendon (STG) graft, and 25 patients (15 men, 10 women; average age, 28years; range, 15-59years) who underwent the ACL reconstruction surgery using bone-patellar tendon-bone (BTB) graft were included in this study. The muscular strength of the knee extension and flexion compared to non-injury side was measured by an isokinetic dynamometer at a velocity at 60°/s preoperatively, and postoperative measurements were performed at 6, 9months, and 1 year after the ACL reconstruction surgery. Covariates that influenced the outcome of the force of knee extension at 12months were the preoperative muscular strength [p = 0.045, odds ratio (OR): 1.105, 95% confidence interval (CI): 1.002-1.219] and muscular strength at 6months after surgery (p = 0.040, OR: 1.155, 95% CI: 1.006-1.326). Only muscle strength at 6months after surgery influenced the outcome of the force of the knee flexion at 1 year after surgery. In sub-analysis, muscular strength of the knee extension and flexion was greater in the STG group than in the BTB group at 6months after surgery although there was no difference between muscular strength of the knee extension in the STG group and that in BTB group at 1 year. Recovery of knee extension strength at a year after ACL reconstruction was significantly associated with preoperative muscular strength and muscle recovery at 6months. Age and graft type might be related to the muscle strength recovery. Preoperative and early postoperative strength training could improve the recovery of knee extension strength, which would support an earlier return to sports after ACL reconstruction.

Increases in Joint Laxity After Anterior Cruciate Ligament Reconstruction Are Associated With Sagittal Biomechanical Asymmetry

To investigate the longitudinal changes in landing mechanics and knee kinematics for patients both before and 3years after anterior cruciate ligament reconstruction (ACLR) and to investigate the association between changes in landing mechanics and magnetic resonance knee kinematics. Thirty-one ACLR patients were included in the study. All patients underwent magnetic resonance imaging and biomechanical analysis of a drop-landing task using the injured knee and contralateral knee preoperatively and at 6months and 3years after ACLR. For evaluations of knee joint anteroposterior laxity, tibial position was calculated using quantitative loaded magnetic resonance methods. The ACLR knee exhibited a significantly lower peak vertical ground reaction force and peak external knee flexion moment and angle at 6months compared with the contralateral knee; however, the differences were resolved at 3years. Tibial position was significantly more anterior on the injured side, and the side-to-side difference (SSD) in tibial position exhibited a significant increase from 6months to 3years. Among ACLR knees, a greater SSD in peak knee flexion moment at 6months was associated with an increase in the SSD in anterior tibial translation from 6months to 3years. Although landing mechanics and clinical outcomes recovered in patients with ACLR in this study, anteroposterior translation failed to be restored at 3years after surgery. In addition, patients who have low knee flexion moments in early stages could have greater anteroposterior laxity. Because of the adverse consequences of abnormal knee kinetics on anterior laxity after ACLR, efforts to improve knee movement patterns should be initiated.

Effects of Ankle Muscle Fatigue and Visual Behavior on Postural Sway in Young Adults.

Ankle muscle fatigue has been shown to increase body sway. In addition, body sway in quiet upright standing is reduced when saccadic eye movements are performed. The purpose of this study was to investigate the effects of visual information manipulation on postural control during ankle muscle fatigue in young adults. Twenty young adults performed: (1) two 60-s trials in quiet bipedal standing with eyes open, eyes closed, and while performing saccadic eye movements; (2) maximum voluntary isometric contractions in a leg press device, custom-made to test ankle plantar flexion force; (3) a calf raise exercise on top of a step to induce ankle muscle fatigue; and (4) a repetition of items 1 and 2. Postural sway parameters were compared with two-way ANOVAs (vision condition × fatigue; p < 0.05). Ankle muscle fatigue increased anterior-posterior and medial-lateral displacement and RMS of sway, as well as sway area. Saccadic eye movements reduced anterior-posterior displacement and RMS of sway and area of sway compared to eyes open and eyes closed conditions. Both saccadic eye movements and eyes closed increased the frequency of AP sway compared to the eyes open condition. Finally, anterior-posterior displacement, anterior-posterior RMS, and both anterior-posterior and medial-lateral sway frequency were affected by an interaction of fatigue and vision condition. Without muscle fatigue, closing the eyes increased anterior-posterior displacement and RMS of sway, compared to eyes open, while during muscle fatigue closing the eyes closed reduced anterior-posterior displacement and had no significant effect on anterior-posterior RMS. In conclusion, body sway was increased after induction of ankle muscle fatigue. Saccadic eye movements consistently reduced postural sway in fatigued and unfatigued conditions. Surprisingly, closing the eyes increased sway in the unfatigued condition but reduced sway in the fatigued condition.

Superior mobility of knee parts with dual-versus single-axis hinge for extravehicular activity without prebreathing

The current U.S. extravehicular activity (EVA) suit is pressurized at 0.29 atm, which creates a risk of decompression sickness (DCS). If higher mobility is acquired, higher inner pressure is allowed. We previously demonstrated a wider range of motion (ROM) with lower muscle force using an elastic glove pressurized at 0.65 atm compared with a nonelastic glove pressurized at 0.29 atm, which simulated the current U.S. EVA suit. Pressurization at 0.65 atm is the lowest pressure that avoids DCS without prebreathing. For larger joints, other restraint parts are needed to depress ballooning of the elastic material during pressurization. In the present study, we developed hard restraint parts for the knee joint covering the elastic garment for the lower limb, and compared the ROM and flexion force between a dual and single axis during pressurization at 0.65 atm. The joint motion and force required during flexing action were recorded. During flexion, the ROM was significantly larger and the peak force was significantly lower with the dual-than single-axis part. Thus, a dual axis of hard restraint part has higher mobility than a single axis during pressurization without a risk of DCS.

MEDIAL AND LATERAL HAMSTRINGS RESPONSE AND FORCE PRODUCTION AT VARYING DEGREES OF KNEE FLEXION AND TIBIAL ROTATION IN HEALTHY INDIVIDUALS.

Hamstring weakness is a contributor to lower extremity pathology. Influence of knee flexion and tibial rotation on hamstrings muscle activation and knee flexion force has not been documented in the literature. The purpose of the study was to determine the angle of knee flexion and tibial rotation that elicits the greatest knee flexion force and hamstrings activation in healthy, physically active adults. Descriptive, observational cohort study. Eighteen young healthy adults were recruited for study participation. Each individual performed maximal voluntary isometric hamstrings contractions at six different knee flexion angles (15 °, 30 °, 45 °, 60 °, 75 ° & 90 °), each positioned at three different tibial rotation positions (internal rotation, neutral rotation and external rotation). Electromyographic activity of the medial and lateral hamstrings and knee flexion force production were recorded. On average, greatest force production was recorded at 30 ° knee flexion with tibia either in neutral rotation (124.1% of max) or in external rotation (123.5% of max). This same lower limb orientation also produced the highest amount of lateral hamstring activation (156.4% of max). Results also showed that force production and lateral hamstring activation decreased as knee flexion angle increased. Muscle activation for the medial hamstrings was not affected by knee flexion angle but did show higher activation in neutral or tibial internal rotation. The results of the current research describe the relationship between knee flexion and tibial rotation and their effect on overall knee flexion force production and hamstrings activation. This research provides key insights about the specific knee joint angles and tibial orientation that may be preferred in exercise prescription for maximizing hamstring activation. Level III.

Hemicraniectomy in Traumatic Brain Injury: A Noninvasive Platform to Investigate High Gamma Activity for Brain Machine Interfaces

Brain-machine interfaces (BMIs) translate brain signals into control signals for an external device, such as a computer cursor or robotic limb. These signals can be obtained either noninvasively or invasively. Invasive recordings, using electrocorticography (ECoG) or intracortical microelectrodes, provide higher bandwidth and more informative signals. Rehabilitative BMIs, which aim to drive plasticity in the brain to enhance recovery after brain injury, have almost exclusively used non-invasive recordings, such electroencephalography (EEG) or magnetoencephalography (MEG), which have limited bandwidth and information content. Invasive recordings provide more information and spatiotemporal resolution, but do incur risk, and thus are not usually investigated in people with stroke or traumatic brain injury (TBI). Here, in this paper, we describe a new BMI paradigm to investigate the use of higher frequency signals in brain-injured subjects without incurring significant risk. We recorded EEG in TBI subjects who required hemicraniectomies (removal of a part of the skull). EEG over the hemicraniectomy (hEEG) contained substantial information in the high gamma frequency range (65-115 Hz). Using this information, we decoded continuous finger flexion force with moderate to high accuracy (variance accounted for 0.06 to 0.52), which at best approaches that using epidural signals. These results indicate that people with hemicraniectomies can provide a useful resource for developing BMI therapies for the treatment of brain injury.

The impact of impairment on kinematic and kinetic variables in Va’a paddling: Towards a sport-specific evidence-based classification system for Para Va’a

ABSTRACT Para Va’a is a new Paralympic sport in which athletes with trunk and/or leg impairment compete over 200 m. The purpose of this study was to examine the impact of impairment on kinematic and kinetic variables during Va’a ergometer paddling. Ten able-bodied and 44 Para Va’a athletes with impairments affecting: trunk and legs (TL), legs bilaterally (BL) or leg unilaterally (UL) participated. Differences in stroke frequency, mean paddling force, and joint angles and correlation of the joint angles with paddling force were examined. Able-bodied demonstrated significantly greater paddling force as well as knee and ankle flexion ranges of movement (ROM) on the top hand paddling side compared to TL, BL and UL. Able-bodied, BL and UL demonstrated greater paddling force and trunk flexion compared to TL, and UL demonstrated larger bottom hand paddling side knee and ankle flexion ROM compared to BL. Significant positive correlations were observed for both male and female athletes between paddling force and all trunk flexion angles and ROM in the trunk and pelvis rotation and bottom hand paddling side hip, knee and ankle flexion. The results of this study are important for creating an evidence-based classification system for Para Va’a.

Semiology of hyperkinetic seizures of frontal versus temporal lobe origin.

Hyperkinetic seizures are usually associated with frontal lobe epilepsy. However, some patients have hyperkinetic seizures of temporal lobe origin. The semiological differences in hyperkinetic seizures between frontal and temporal lobe epilepsy have not been well studied. Here, we retrospectively assessed ictal semiology in order to distinguish between hyperkinetic seizures of frontal lobe origin and those of temporal lobe origin. We retrospectively reviewed data on patients who had undergone surgery for hyperkinetic seizures of temporal or frontal lobe origin and achieved favourable seizure outcomes (Engel Class I) with a minimum postoperative follow-up of 24 months. We reviewed seizure histories, imaging reports, video-EEG monitoring data, operative records, and pathological findings. We analysed and compared the hyperkinetic semiology of video-recorded seizures of temporal lobe origin and those of frontal lobe origin. Forty hyperkinetic seizures in eight patients (seven adult patients and one 12-year-old patient) with temporal lobe epilepsy and 45 hyperkinetic seizures in nine patients (eight adult patients and one 16-year-old patient) with frontal lobe epilepsy were analysed. Emotional facial expressions (such as fear, laughing, or anger), bilateral forceful elbow flexion, bilateral forceful grasping, facial flushing, and bilateral facial contraction were observed significantly more frequently in seizures of frontal lobe origin. Oroalimentary automatisms, seizures during wakefulness, salivation, and bilateral drop of the corners of the mouth were observed significantly more frequently in seizures of temporal lobe origin. Observation of a number of signs during hyperkinetic manifestations may help to predict whether a seizure originates from the frontal lobe or the temporal lobe.

Suturing and wiring a novel technique for Osteosynthesis of inferior pole patella fracture: A prospective comparative study

Background: Osteosynthesis and partial patellectomy with patellar tendon repair are accepted procedures for inferior pole fracture of patella. Fractures of lower end of patella are usually avulsion injuries due to forceful flexion of knee against contracted quadriceps muscle. Multiple small fragments attached to patellar tendon make the management difficult. We conducted a prospective study of clinical and radiological outcome of inferior pole of patellar fractures treated with patellar tendon repair with non absorbable Ethibond and circumferential wiring. We compared the results with those of mid patellar fractures treated with modified tension band wiring technique. Materials: We included all patients with lower pole patella fractures, presented to our department from 2012 to 2015. We included patients with fracture 34 A1 (b) (extra articular lower pole) and 34C1.3 (complete articular distal 3rd fracture). These fractures were fixed with Ethibond 5 by making transosseous longitudinal drill holes and supplemented with circumferential stainless steel wires. Bostman scoring system was used to analyze and assess clinical results. We compared the results with midpatellar fractures treated by tension band wiring at the end of follow up period. Results: We recruited 21 patients with inferior pole patella fractures. Independent T Test was used to compare the means of Bostman scoring, flexion and loss of extension of knee joint between two groups of patients. Anterior knee pain and implant loosening was found more prevalent in midpatellar fracture treated by tension band wiring technique and required implant removal. There was no significant difference between two groups of patients. Conclusion: Lower pole patella fracture can be successfully treated by this novel technique of fixation with less number of complications. Comminuted lower pole fractures which otherwise needed excision may be preserved with this technique.

Involuntary hamstring muscle activity reduces passive hip range of motion during the straight leg raise test: a stimulation study in healthy people

BackgroundInvoluntary hamstring muscle activity is present in some people during the straight leg raise test, but it is not known to what extent involuntary muscle activity limits passive joint range of motion. This study aimed to determine whether small amounts of involuntary hamstring activity limit passive hip range of motion during the straight leg raise test in healthy people.MethodsThirty healthy subjects were recruited from The University of Sydney. As the hamstring muscles were continuously stimulated to generate 0, 2.5, 5, 7.5 and 10% of knee flexion maximal voluntary contraction force, an investigator blinded to the amount of stimulation performed a straight leg raise test by passively raising the tested leg while keeping the knee extended. The test was stopped when the knee started to flex, at which point hip range of motion was recorded.ResultsOn average, passive hip range of motion decreased by 0.6° for every 1% increase in knee flexion force caused by muscle activation (95% CI 0.3 to 0.9°, p = 0.0012). Subjects were instructed to fully relax when the straight leg raise test was performed, but a small amount of involuntary muscle activity (median 2.4% of maximal activation) was present during the trial without stimulation.ConclusionsSmall amounts of involuntary hamstring muscles activity reduce passive hip range of motion during the straight leg raise test in healthy people.Trial registrationThe protocol for this study was registered with the Open Science Framework, reference: https://osf.io/fejpf/. Registered 9 March 2017.

Minimal force transmission between human thumb and index finger muscles under passive conditions.

It has been hypothesized that force can be transmitted between adjacent muscles. Intermuscle force transmission violates the assumption that muscles act in mechanical isolation, and implies that predictions from biomechanical models are in error due to mechanical interactions between muscles, but the functional relevance of intermuscle force transmission is unclear. To investigate intermuscle force transmission between human flexor pollicis longus and the index finger part of flexor digitorum profundus, we compared finger flexion force produced by passive thumb flexion after one of three conditioning protocols: passive thumb flexion-extension cycling, thumb flexion maximal voluntary contraction (MVC), and thumb extension stretch. Finger flexion force increased after all three conditions. Compared to passive thumb flexion-extension cycling, change in finger flexion force was less after thumb extension stretch (mean difference 0.028 N, 95% CI 0.005 to 0.051 N), but not after thumb flexion MVC (0.007 N, 95% CI -0.020 to 0.033 N). As muscle conditioning changed finger flexion force produced by passive thumb flexion, the change in force is likely due to intermuscle force transmission. Thus, intermuscle force transmission resulting from passive stretch of an adjacent muscle is probably small enough to be ignored.

Biceps tenodesis versus tenotomy in isolated LHB lesions: a prospective randomized clinical trial.

Currently there exists no clear evidence concerning the surgical treatment of LHB lesions with either tenotomy or tenodesis. The aim of the study is therefore to evaluate elbow flexion and forearm supination force as well as the biceps muscle distalization according to both techniques in isolated LHB lesions. Consecutive patients aged 40-70years with shoulder arthroscopies for isolated SLAP or biceps pulley lesions were prospectively randomized to arthroscopic suprapectoral intraosseous LHB tenodesis or tenotomy. Pre-, 6 and 12months postoperatively, the SST, ASES, Constant-Murley and LHB scores were recorded. The elbow flexion force was measured in 10°/90° flexion, the supination force in neutral/pronation position. In addition, the maximum upper-arm circumference and its position relative to the radial epicondyle of the humerus were evaluated preoperatively and in follow-up. 20/22 patients (mean age 52.0 ± 8.5; range 36-63 years, 11 male) completed the follow-up. 9/20 were treated with LHB tenodesis (mean age 51.5 ± 9.5; range 37-63 years, 7 male) and 11/20 with tenotomy (mean age 52.8 ± 8.0; range 36-62 years, 4 male). The force measurements and scores showed no significant difference after 12months. Tenodesis achieved a significant increase in force 6months postoperatively compared to preoperatively. One tenodesis patient and three tenotomy patients showed a postoperative popeye-sign deformity. This prospective randomized study comparing LHB tenodesis and tenotomy in isolated LHB lesions has shown no significant difference in elbow flexion and forearm supination force and clinical scores after 12months. After LHB tenotomy, there was a non-significant trend for a higher rate of popeye-sign deformities of the upper arm and biceps muscle cramps.

Leg muscle strength is reduced and is associated with physical quality of life in Antineutrophil cytoplasmic antibody-associated vasculitis

ObjectivePhysical quality of life is reduced in ANCA-associated vasculitis (AAV). This study aims to investigate whether this may be explained by reduced muscle strength and physical activity resulting from disease damage and steroid myopathy.MethodsForty-eight AAV patients were sequentially included from the outpatient clinic. Patients in different stages of disease and treatment underwent measurements of muscle strength and anthropometric parameters. Patients filled in physical activity (Baecke) and quality of life questionnaires (RAND-36) and carried an accelerometer for a week. Muscle strength and physical activity were compared to quality of life, prednisolone use and disease duration.ResultsMost AAV patients had lower knee extension (76%) and elbow flexion (67%) forces than expected based on healthy norms. Also, physical (P<0.001) and mental (P = 0.01) quality of life were significantly reduced compared to healthy norm values. Lower knee extension force (P = 0.009), younger age <70 (P<0.001) and relapse of vasculitis (P = 0.003) were associated with lower age-adjusted physical quality of life. Lower Baecke index (P = 0.006), higher prednisolone dose (P = 0.005) and ENT involvement (P = 0.006) were associated with lower age-adjusted mental quality of life. Leg muscle strength showed no association with current or cumulative prednisolone use. Disease duration was longer in patients with knee extension force below healthy norms (P = 0.006).ConclusionKnee extension force and physical activity are positively associated with quality of life in AAV. Knee extension force decreases with longer disease duration, suggesting that disease- and treatment-related damage have a cumulative negative effect on muscle strength.

Biomechanical comparison of the proximal interphalangeal joint arthrodesis using a compression wire.

Arthrodesis of the proximal interphalangeal joint of the finger is a common procedure for the treatment of osteoarthritis. The aim of this biomechanical study was to compare the primary stability of one, respectively, two compression wires to intraosseous wiring and tension band wiring for the arthrodesis. The stability of the arthrodesis was tested by applying flexion (n = 11) and extension (n = 10) force with 10° bending. Arthrodesis was achieved by one, respectively, two crossed compression wires and intraosseous wiring. In a control group (n = 11) tension band wiring was tested to 10° flexion and extension as well. Mean values for flexion bending for intraosseous wiring were 10.94N, for one compression wire 12.82N, for tension band wiring 17.95N, and for two crossed compression wires 20.42N. Mean values for extension bending were 9.71N for intraosseous wiring, 13.63N for one compression wire, 21.43N for tension band wiring and 22.56N for two crossed compression wires. The primary stability of the compression wires was statistically significant superior to intraosseous wiring. In comparison to tension band wiring which showed an intermediate stability. The application of a compression wire could be considered for further clinical testing in the arthrodesis of interphalangeal joints.

Isokinetic Profile of Elbow Flexor and Extensor Muscles in Climbers and Non-Climbers

Background: Sport climbing places high mechanical demand on the elbow, which is the third most common region to be injured in climbing. It has been suggested that overuse injuries are associated with disrupted muscle balance. However, little is known about the muscle balance around the elbow.Aim: To investigate moment and work profile of the elbow flexors and extensors in climbers and non-climbers.Methods: Climbers (n=16) and non-climbers (n=18) volunteered to participate in the study. Each participant was examined bilaterally for concentric elbow flexion and extension muscle forces. Experimental equipment included the isokinetic dynamometer at speeds of 60°/sec and 180°/sec. Outcome measures included peak moment, average moment, total work and average work. Flexion/extension ratio was calculated for all measures.Results: Elbow extensor muscles were significantly stronger than the elbow flexors in both groups (p<0.001), with a flexor/extensor total work ratio ranging from 0.76-0.86. Surprisingly, no significant group differences were found for any measure between climbers and non-climbers.Conclusion: This study did not demonstrate a difference in elbow muscle work and moment between climbers and non-climbers, but did show elbow extensors were stronger than flexors. It may be that isokinetic testing is not sensitive to the functional strength developed in climbing and further research is needed to integrate additional functional strength evaluations.

Relationship between Toe Flexion Force and Balance Scale

Relationship between Toe Flexion Force and Balance Scale

Regenerative rehabilitation: exploring the synergistic effects of rehabilitation and implantation of a bio-functional scaffold in enhancing nerve regeneration.

Clinically, rehabilitation is one of the most common treatment options for traumatic injuries. Despite that, recovery remains suboptimal and recent breakthroughs in regenerative approaches may potentially improve clinical outcomes. To date, there have been numerous studies on the utilization of either rehabilitative or regenerative strategies for traumatic injury treatment. However, studies that document the combined effects of rehabilitation and regenerative tissue engineering options remain scarce. Here, in the context of traumatic nerve injury treatment, we use a rat spinal cord injury (SCI) model as a proof of concept to evaluate the synergistic effects of regenerative tissue engineering and rehabilitation. Specifically, we implanted a pro-regenerative hybrid fiber-hydrogel scaffold and subjected SCI rats to intensive rehabilitation. Of note, the rehabilitation session was augmented by a novel customized training device that imparts normal hindlimb gait movements to rats. Morphologically, more regenerated axons were observed when rats received rehabilitation (∼2.5 times and ∼2 times enhancement after 4 and 12 weeks of recovery, respectively, p < 0.05). Besides that, we also observed a higher percentage of anti-inflammatory cells (36.1 ± 12.9% in rehab rats vs. 3.31 ± 1.48% in non-rehab rats, p < 0.05) and perineuronal net formation in rehab rats at Week 4. Physically, rehab animals were also able to exert higher ankle flexion force (∼0.779 N vs. ∼0.495 N at Week 4 and ∼1.36 N vs. ∼0.647 N at Week 12 for rehab vs. non-rehab rats, p < 0.001) and performed better than non-rehab rats in the open field test. Taken together, we conclude that coupling rehabilitation with regenerative scaffold implantation strategies can further promote functional recovery after traumatic nerve injuries.