Metatarsophalangeal Joint Extension Research Articles

Effect of Increase the First Metatarsophalangeal Joint Extension and Ankle Dorsiflexion Using an Elastic Band on Ankle Stability

Background It is known that ankle stability is required to maintain balance. However, metatarsophalangeal joint movement is related to ankle stability, there is no study that increases the first metatarsophalangeal joint extension and ankle dorsiflexion affect together in ankle stability. Objectives The purpose of this study was to determine the effect of an elastic band on ankle stability during one leg standing on an unstable surface. Methods A total of 12 healthy adult volunteers were recruited for this study. The total distance of the marker which presents the center of mass displacement was measured using the camera - Kinovea®. The difference between with and without an elastic band was analyzed using the paired t-test with p < 0.05 as the significant level. Results The total distance of the center of mass was significantly decreased (p < 0.001) when one leg standing on an unstable surface with an elastic band versus without an elastic band. Conclusions The present findings demonstrate that using an elastic band on the first metatarsophalangeal joint and the ankle improves ankle stability during one leg standing on an unstable surface in healthy adults.

Evaluation of range of motion of hallux metatarsophalangeal and interphalangeal joints after periarticular osteotomies

Objective: Evaluate the impact of Chevron and extended Chevron techniques associated with Akin osteotomy on the range of motion (ROM) of hallux metatarsophalangeal joint (MPJ) and interphalangeal joint (IPJ) after three months and one year. Methods: Sixteen patients (17 feet) were evaluated for the ROM of hallux MPJ and IPJ pre-and postoperatively, the flexion-extension measurements were performed using a goniometer. Results: Comparing the pre-and postoperative measurements at three months and one year, the ROM decreased in MPJ extension and flexion, 9o and 5o, respectively, and IPJ flexion, 5o. The values presented statistical significance according to the analysis demonstrated (p&gt;0.05). However, the decrease in IPJ extension was not statistically significant (decrease of 0.8o and p&lt;0.05). Conclusions: Periarticular osteotomies of hallux MPJ had a significant decrease in the ROM after three months and one year. Level of Evidence II; Therapeutic Studies - Investigating the Results of Treatment; Prospective Comparative Study.

Influence of metatarsophalangeal joint stiffness on take-off performances and lower-limb biomechanics in jump manoeuvres

ABSTRACT Forefoot and toes are prominent regions for locomotion and individual metatarsophalangeal joint (MTPJ) stiffness may be linked to jump take-off mechanics and performances. However, little is known about the relationships between MTPJ stiffness and take-off related variables. This study examined the relationship between individual MTPJ stiffness and biomechanical variables under various vertical countermovement jumps (CMJ) conditions. We measured MTPJ stiffness on 21 male university basketball players and then asked them to perform jumps under single, consecutive and running CMJ conditions. Pearson’s correlation coefficient was employed to examine the relationships between MTP passive stiffness and each jumping performance, ground reaction force (GRF) and joint kinematic and kinetic variables. The results indicated that MTPJ stiffness significantly correlated with maximum jump height (r = 0.49, moderate), peak take-off velocity (r = 0.47, moderate), peak take-off ankle plantarflexion moment (r = 0.68, strong), peak dorsiflexion moment (r = 0.60, strong) and peak take-off ankle power (r = 0.44, moderate) in consecutive CMJ. Only a moderate correlation between MTPJ stiffness and peak MTPJ extension take-off velocity (r = −0.46, moderate) was determined in a single CMJ. There were no significant correlations found in running CMJ conditions. These findings imply that higher MTPJ stiffness of participants was related to improved jump performances in consecutive jumps.

Prediction of callus and ulcer development in patients with diabetic peripheral neuropathy by isosceles triangle-forming tuning fork.

Objectives:Tuning fork vibration sensation testing is widely used as a diagnostic test to detect diabetic neuropathy. However, evidence-based literature indicates that reliability between examiners is low. Attaching isosceles triangle diagrams on tuning forks lowers the discrepancy between examiners. This study aimed to analyze the relationship between vibration sensation measurement using an improved tuning fork and the presence of callus and wound development in patients with diabetic peripheral neuropathy.Methods:Participants included 56 general older adults and 52 patients with diabetic peripheral neuropathy. The methods included confirmation of the presence or absence of callus, range of motion of the ankle and the first metatarsophalangeal joint, vibratory sensitivity of the medial malleolus and the dorsal aspect of the first distal phalanx using an improved tuning fork, and touch-pressure sensitivity of the plantar aspect of the hallux. Patients with diabetic peripheral neuropathy were followed up for 3 years to check for the presence or absence of wounds.Results:When compared with the general older adults, the patients with diabetic peripheral neuropathy had significantly lower touch-pressure sensitivity (p < 0.01), vibratory sensitivity at the distal phalanx (p < 0.01) and medial malleolus (p < 0.01), ankle dorsiflexion range of motion (p < 0.01), and metatarsophalangeal joint extension range of motion (p < 0.01). The area under the receiver operating characteristic curve with callus formation was 0.93 for the medial malleolus and 0.96 for the distal phalanx, indicating that the accuracy of the distal phalanx was higher (p < 0.01) than the medial malleolus. According to the Cox proportional hazard analysis, the vibratory sensitivity of the distal phalanx was a significant risk factor for ulcer development (p < 0.05).Conclusion:These findings suggest that the vibration sensation test, which we improved via the technique described in this study, is useful for predicting the occurrence of callus and ulcer.

Structural and functional foot and ankle characteristics associated with falls in older people

Falls affect approximately one in three older people, and foot problems are amongst the modifiable potential risk factors. what are the associations between foot and ankle functional and structural characteristics with falls in community-dwelling older adults? One hundred eighty-seven community-dwelling older adults (106 females) aged 62-90 years (mean 70.5 ± 5.2) from Isfahan, Iran were recruited. Foot and ankle structure and function (including foot posture, range of motion, muscle strength, deformity, pain and plantar loading patterns during walking) were measured. Fall history was documented in the preceding year. Univariate analyses compared fallers and non-fallers on all variables to determine significant differences and logistic regression analysis identified variables independently associated with falls. Seventy-four participants (39.9 %) had experienced a fall in the previous year. Logistic regression analysis revealed that less first metatarsophalangeal joint extension (odds ratio 0.82, 95 % CI 0.73-0.91), less plantarflexor muscle strength (odds ratio 0.29, 95 % CI 0.15-0.55), greater pressure-time integral in the medial forefoot (odds ratio 2.65, 95 %CI 1.10-6.38), greater center of pressure velocity in the forefoot (odds ratio 1.27, 95 % CI 1.07-1.49) and greater foot pain (odds ratio 1.09, 95 % CI 1.02-1.16) were significantly and independently associated with falls after accounting for physiological falls risk factors. We have identified several structural and functional foot and ankle characteristics associated with falling in older people. Future development of interventions to help prevent or treat these potentially modifiable risk factors may help decrease the risk of falling in this population.

Chronic Plantar Heel Pain Is Principally Associated With Waist Girth (Systemic) and Pain (Central) Factors, Not Foot Factors: A Case-Control Study.

To determine the independent associations of potential clinical, symptom, physical activity, and psychological factors with chronic plantar heel pain. Case-control. We investigated associations by comparing 220 participants with chronic (more than 3 months in duration) plantar heel pain to 100 age- and sex-matched controls, who were recruited randomly from the electoral roll. Exposures measured were waist girth, body mass index, body composition, clinical measures of foot and leg function, physical activity via accelerometry, depression and pain catastrophizing, symptoms of prolonged morning stiffness anywhere in the body, and multisite pain. Data were analyzed using multivariable conditional logistic regression. Waist girth (centimeters) (odds ratio [OR] = 1.06; 95% confidence interval [CI]: 1.03, 1.09), ankle plantar flexor strength (kilograms) (OR = 0.98; 95% CI: 0.97, 0.99), pain at multiple sites (pain at 1 other site: OR = 2.76; 95% CI: 1.29, 5.91; pain at 4 or more other sites: OR = 10.45; 95% CI: 3.66, 29.81), and pain catastrophizing status (none, some, or catastrophizer) (some: OR = 2.91; 95% CI: 1.33, 6.37; catastrophizer: OR = 6.79; 95% CI: 1.91, 24.11) were independently associated with chronic plantar heel pain. There were univariable but not independent associations with morning stiffness, first metatarsophalangeal joint extension range of motion, depression, and body mass index. There were no significant associations with physical activity or body composition (bioelectrical impedance analysis). Waist girth, ankle plantar flexor strength, multisite pain, and pain catastrophizing, but not foot-specific factors, were independently associated with chronic plantar heel pain. Of these 4 factors, 3 (waist girth, multisite pain, and pain catastrophizing) were central or systemic associations. J Orthop Sports Phys Ther 2021;51(9):449-458. Epub 7 May 2021. doi:10.2519/jospt.2021.10018.

The effects of wearing high heeled shoes on the muscles and joints of lower limb

Abstract Study aim: The aim of this study is to investigate whether the lower extremity muscles’ force/torque/strength and range of motion may be affected in females wearing high heeled shoes and not wearing high heeled shoes. Material and methods: The study was carried out with 136 females aged between 18 and 45 years. The first group consisted of 66 females wearing 5 cm or higher high heeled shoes. The second group consisted of 70 females wearing shoes having heel height less than 5 cm. The Nicholas Manual Muscle Tester was used to evaluate lower extremity muscle force/torque/strength, while range of motion was assessed with an electronic goniometer. The SPSS 21.0 program was used for statistical analysis. Results: A significant difference was found in the lower extremity muscles’ force (except for hip adduction, dorsiflexion, metatarsophalangeal joint and interphalangeal joint extension), and muscles’ torque (except for hip adduction, dorsiflexion and left tibialis anterior muscle) and muscles’ strength values (except for hip adduction, dorsiflexion and tibialis anterior muscle). Also, as heel height increased, the range of motion of hip joint flexion, internal rotation and plantar flexion increased significantly. Conclusions: Excessive use of high heeled shoes can cause changes in muscle force/torque/strength and joint range of motion.

The effects of acute physical fatigue on sauté jump biomechanics in dancers

ABSTRACT Dancers spend large amounts of time practicing and performing, where fatigue may occur, resulting in adverse movement patterns. The purpose of this study was to compare sauté landings before and after acute physical fatigue in experienced female dancers. Twenty-one dancers completed 10 sauté jumps before and after a dance-specific fatigue protocol. A 12-camera motion capture system and a force plate were utilized to collect three-dimensional kinematic and kinetic data. After fatigue, dancers demonstrated an increase in mediolateral centre of mass displacement, pelvis excursion, peak knee abduction, peak ankle eversion and external rotation, as well as decreased peak metatarsophalangeal (MTP) joint extension, indicating less desirable movement patterns. Peak vertical ground reaction force was decreased after fatigue due to a softer landing strategy, demonstrated by increased peak hip flexion, knee flexion, and ankle dorsiflexion. There was some indication of shifting demands demonstrated by an increased peak knee extensor moment and decreased peak MTP flexor moment after fatigue. With jump landing kinematics and kinetics affected after only an average of 5 minutes of dancing, dancers may benefit from developing greater endurance and more eccentric strength to allow them to slow down properly while landing and to sustain the aesthetic demands throughout performance.

The Effect of Knee Flexion on Active and Passive Popliteal Venous Flow When Using Crutches or Knee Scooter While Immobilized

Category:Trauma; OtherIntroduction/Purpose:Knee flexion has been demonstrated to impede popliteal venous return with large effect size among patients lying supine for surgery. Passive popliteal flow impedance has also been suggested to occur with knee scooter usage due to knee flexion. This study compared the effect of knee flexion angles on popliteal venous return between upright, crutch and knee scooter positioning when immobilized. Further, the countervailing effect of standardized hallux musculovenous pump activation was observed.Methods:This was an IRB approved study of young, healthy volunteers. Popliteal venous diameter and flow metrics were assessed with venous ultrasonography and compared between straight leg, crutch, and knee scooter positioning while wearing a walking boot and nonweightbearing. Flow was assessed with muscles at rest and with hallux musculovenous pump activation via active oscillation between hallux metatarsophalangeal joint extension and flexion at one motion per second (0.5 Hz) as paced by a metronome. Observer consistency was assessed. Paired-sample Student’s t-test and the Wilcoxon signed rank tests were used to assess within-subject differences for diameter and venous flow parameters, respectively. Knee flexion and musculovenous pump activation effects sizes were calculated. A priori sample size indicated 24 subjects were needed to achieve 80% power to detect a significant ( p < 0.006 ) difference in medial flow for any of 8 comparisons, assuming large effect sizes.Results:16 of 24 (67%) subjects were female. Twelve limbs (50%) were right sided. The mean age was 21.9 years (SD 3.0 years) and the mean body mass index was 21.9 (SD 1.9). Observer consistencies were excellent (0.93 to 0.99). No significant differences in mean vessel diameter, time-averaged mean velocity, and total volume flow occurred. Corresponding knee flexion effect sizes were small (range -0.04 to -0.26). A significant decrease (-24%) in active median time-averaged peak velocity (TAPV) occurred between upright and crutch position (20.89 cm/s vs. 15.92 cm/s, p < 0.001) with a medium effect size (-0.51). Hallux musculovenous pump increased all flow parameters (all p< 0.001) and effect sizes were comparatively larger (>0.6) across all knee flexion positions.Conclusion:Compared to values reported for supine individuals, upright passive popliteal venous return was observed to be markedly diminished at all knee flexion angles. Knee flexion had minimal effect on diameter, a small effect in further diminishing TAMV and TVF and a medium effect on diminishing TAPV. Hallux musculovenous pump activiation had a large effect on increasing flow at all knee flexion angles. Patients may well be counseled to use toe motion to counter the negative effects of gravity, and to a lesser extent knee flexion, when using crutches and knee scooters while their ankle is immobilized.

Influence of forefoot bending stiffness on American football performance and metatarsophalangeal joint bending angle

ABSTRACT Changes in forefoot bending stiffness have been shown to affect metatarsophalangeal peak bending angles as well as athletic performance. Increasing bending stiffness tends to reduce peak bending angles, which could potentially reduce hyperextension injuries such as turf toe. Limited information is available, however, on the efficacy of increasing forefoot bending stiffness on large-sized athletes such as those that participate in American Football, with prior studies being conducted on smaller athlete populations. Therefore, the purpose of this study was to determine the influence of increased forefoot bending stiffness on metatarsophalangeal joint extension and athletic performance of grid-iron football players. Ten varsity grid-iron football players performed four National Football League combine movements in a motion capture laboratory in three footwear conditions of varying bending stiffness: Soft (12.7 N/mm), Control (23.8 N/mm), Stiff (42.2 N/mm). None of the footwear conditions significantly altered the maximum metatarsophalangeal bending. Therefore, to reduce metatarsophalangeal hyperextension injuries in American football players a greater amount of forefoot bending stiffness may be required. Performance differences were present only during the five-metre sprint acceleration, with athletes having an improved performance in the Control and Stiff conditions. This improved performance was due to an increased horizontal impulse and improvements in power generation at the ankle joint.

The efficacy of an intramedullary nitinol implant in the correction of claw toe or hammertoe deformities.

A multitude of procedures has been described in the literature for the treatment of lesser toe deformities and there is currently no general consensus on the optimal method of fixation. The aim of this study is to assess the clinical and radiological outcomes of an intramedullary nitinol implant for the correction of lesser toe deformities, and to determine if the distal interphalangeal (DIP) joint and metatarsophalangeal (MTP) joint are modified during patient follow-up after correction of the PIP joint. A prospective analysis of 36 patients with claw toe or hammertoe who were treated with an intramedullary nitinol implant. Clinical manifestations and angulation of the metatarsophalangeal, proximal and distal interphalangeal (MTP, PIP, DIP) joints were evaluated in radiographic studies preoperatively, at first medical revision post-surgery, and after a minimum of 1year of follow-up. Complications such as non-union rate, implant rupture, and implant infection were also evaluated during follow-up. All patients were women with an average age of 65.5 (range 47-82) years. The average follow-up time was 2.4 (range 1-5.7) years. Fifty intramedullary nitinol implants were used. The MTP joint extension and PIP joint flexion decreased by 15.9° (95% CI - 19.11 to - 12.63) and 49.4° (95% CI - 55.29 to - 43.52), respectively, at the end of follow-up. Moreover, the DIP joint flexion increased progressively during follow-up (13.7° pre-surgery versus 35.6 in last medical check-up, 95% CI 13.24-30.57). There were four (8%) asymptomatic implant ruptures. The rate of fusion was 98%. The reduction of the PIP joint using an intramedullary nitinol implant is a good option in lesser toe deformities, with few complications and a high rate of arthrodesis. Moreover, the PIP joint reduction affects both the MTP and DIP joints.

Mechanical Diagnosis and Therapy and Morton's Neuroma: A Case Report.

Purpose: Morton's neuroma (MN) is a neuralgia involving the common plantar digital nerves of the metatarsal region. Evidence-based treatment options for this condition are sparse, and physiotherapy's usefulness is limited. Client Description: A woman aged 44 years was referred to physiotherapy for left forefoot pain lasting 3 months. The podiatrist diagnosed MN using ultrasonography. Examination found positive squeeze test, painful interphalangeals and metatarsal heads, and painful metatarsophalangeal joint (MPJ) extension. Intervention: Repeated flexion of MPJ digit II relieved the patient's pain. She was treated six times over 3 months to progress treatment, achieve longer lasting pain relief, and recover function to full pain-free status, including running. Measures and Outcome: The patient's pain reduced after treatment from a variable 2-7 out of 10 on the Numeric Pain Rating Scale to 0 out of 10. After two sessions, the patient's Lower Extremity Functional Scale score improved, from 56 out of 80 to 70 out of 80, and by discharge, it was 73 out of 80. At 6-month follow-up, the patient was still running pain-free. Implications: This article describes the rapid and lasting improvement in chronic forefoot pain associated with MN after mechanical diagnosis and therapy assessment and treatment. Finding new, effective, conservative interventions is important for this condition because so few evidence-supported treatments exist. The findings from this case report demonstrate the benefit derived from exercise-based treatment and may indicate a role for physiotherapy in managing MN.

Metatarsophalangeal joint extension changes ultrasound measurements for plantar fascia thickness

BackgroundUltrasound is an inexpensive method for quantifying plantar fascia thickness, especially in those with plantar fasciitis. Ultrasound has also been used to assess the effectiveness of various treatments for plantar fasciitis by comparing plantar fascia thickness before and after an intervention period. While a plantar fascia thickness over 4 mm via ultrasound has been proposed to be consistent with plantar fasciitis, some researchers believe the 4 mm plantar fascia thickness level to be a dubious guideline for diagnosing plantar fasciitis due to the lack of standardization of the measurement process for plantar fascia thickness. In particular, no universal guidelines exist on the positioning of the metatarsophalangeal (MTP) joints during the procedure and the literature also has inconsistent protocols. The purpose of this study is to investigate and compare the influence of MTP joint extension on plantar fascia thickness in healthy participants and those with unilateral plantar fasciitis.MethodsThe plantar fascia thickness of forty participants (20 with unilateral plantar fasciitis and 20 control) was measured via ultrasound three times at three different MTP joint positions: 1) at rest, 2) 30° of extension from the plantar surface, and 3) maximal extension possible.ResultsThe plantar fascia became significantly thinner as MTP joint extension increased in both the plantar fasciitis group (p < 0.001) and the control group (p < 0.001). In the plantar fasciitis group, the involved plantar fascia was 1.2 to 1.3 mm thicker (p < 0.001) than the uninvolved side depending on the MTP joint position. In the control group, the difference in plantar fascia thickness between the two sides was less than 0.1 mm (p < 0.92) at any MTP joint position.ConclusionsMTP joint position can influence the ultrasound measurement of plantar fascia thickness. It is recommended that plantar fascia thickness measurements be performed with the toes at rest. If MTP joints must be extended, then the toes should be extended maximally and then noted to ensure subsequent ultrasound procedures are repeated. Standardizing the position of the MTP joints is not only important for attaining the most accurate thickness measurement of the plantar fascia, but is also important to researchers who use plantar fascia thickness to determine the effectiveness of various plantar fasciitis interventions.

A simple method for equine kinematic gait event detection.

Previous studies have validated methods for determining kinematic gait events using threshold-based techniques. However, a simple method that can be successfully applied to walk, trot and canter is yet to be identified. To develop a simple kinematic method to identify the timing of hoof contact (hoof-on), peak vertical force and lift off (hoof-off), which can be applied in walk, trot and canter. In vivo method authentication study. Horses (n = 3) were ridden in walk, trot and canter down a runway on which four force plates were arranged linearly. Three-dimensional forces were recorded at a sampling rate of 960 Hz and were synchronised with a 10-camera motion analysis system sampling at 120 Hz. Events identified from vertical ground reaction force (GRFz) data were hoof-on (GRFz>50N), peak vertical force (GRFzpeak ) and hoof-off (GRFz<50N). Kinematic identification of hoof-on and hoof-off events was based on sagittal planar angles of the fore- and hindlimbs. Peak metacarpophalangeal (MCP)/metatarsophalangeal (MTP) joint extension was used to assess the time of GRFzpeak . The accuracy (mean) and precision (s.d.) of time differences between kinetic and kinematic events were calculated for fore- and hindlimbs at each gait. Hoof-off was determined with better accuracy (range: -3.94 to 8.33 ms) and precision (range: 5.43-11.39 ms) than hoof-on across all gaits. Peak MCP angle (range: 5.83-19.65 ms) was a more precise representation of GRFzpeak than peak MTP angle (range: 11.49-67.75 ms). The sample size was small and therefore further validation is required. The proposed method was tested on a single surface. This study proposes a simple kinematic method of detecting hoof-on, hoof-off and GRFzpeak at walk, trot and canter. Further work should focus on validating the methodology in a larger number of horses and should extend the method for use on surfaces with varying levels of compliance.

Relationship between patient-reported outcome measures (PROM) and three measures of foot-ankle alignment in patients with metatarsal head pain: a cross-sectional study.

BackgroundThe aim of the present study is to establish the relationship between foot–ankle patient-reported outcome measures (PROM) and three measures of foot–ankle alignment (MoFAA) in patients with metatarsal head pain.MethodsA cross-sectional study where 206 patients completed three PROMs and a clinician recorded three MoFAA bilaterally (three times each). A reliability analysis of the MoFAA, a correlation analysis (between MoFAA and PROM) and regression analysis (dependent variable: PROM; independent variables: MoFAA) were performed.ResultsPearson’s coefficient changed in each PROM used, ranging from 0.243 (AAOS-FAMShoeComfortScale–FVARight) to 0.807 (FFIIndex–first MTPJEright). Regression indices (R2-corrected) ranged between 0.117 (AAOS-FAMShoeComfortScale) and 0.701 (FFIIndex).ConclusionsThe MoFAA correlated between moderately to strongly with the foot–ankle PROM selected. The level of correlation between MoFAA and PROM was higher when patients with metatarsal head pain were asked about foot health status, pain and function; however, the correlation was poor when the patient was asked about shoe aspects. In addition, the MoFAA variable that achieved the highest correlation value was the first metatarsophalangeal joint extension. The results obtained in this study could be used in future studies to develop tools for assessing and monitoring patients with metatarsal head pain.

Toe Flexor Strength, Flexibility and Function and Flexor Hallucis Longus Tendon Morphology in Dancers and Non-Dancers

Tendinopathy of the flexor hallucis longus (FHL), colloquially referred to as "dancer's tendinitis," is a common condition in dancers and attributed to high demand on this muscle in positions of extreme ankle plantarflexion and metatarsophalangeal (MTP)) flexion and extension. Despite such a high prevalence, there has been little research into preventative or nonsurgical interventions. As a means to identify potential targets for prevention and intervention, this study aimed to characterize toe flexors in dancers by measuring strength, flexibility, function, and FHL tendon morphology. Dancers (n=25) were compared to non-dancers (n=25) in toe flexor isometric strength, first MTP joint range of motion, foot longitudinal arch flexibility, balance ability, endurance during modified heel raises without use of the toes, and FHL tendon thickness, cross-sectional area, and peak spatial frequency. Significant differences were found in functional first MTP joint extension (dancers 101.95°, non-dancers 91.15°, p<0.001), balance ability during single-leg stance on the toes (dancers 11.43 s, non-dancers 5.90 s, p=0.013), and during modified heel raises (dancers 22.20 reps, non-dancers 28.80 reps, p=0.001). Findings indicate that dancers rely on toe flexors more than non-dancers to complete balance and heel raise tasks. Efficacy of using this modified heel raise task with the toes off the edge of a block as a means to train larger plantarflexors and as a nonsurgical intervention should be studied in the future. Improving interventions for FHL tendinopathy will be impactful for dancers, in whom this condition is highly prevalent.

Effects of Ankle Dorsiflexion Flexibility on Forefoot and Toe Plantar Loading During a Weighted Sled Push

First metatarsophalangeal (MTP) joint sprain is an injury increasing in prevalence in football players resulting in a significant loss of participation time. Investigation of the unique plantar loading strategies in football may help identify critical components that predispose an athlete to MTP joint sprains. Furthermore, limitations in ankle dorsiflexion range of motion may increase the loading on the plantar side of the forefoot and hallux during late stance of athletic movements. PURPOSE: Therefore, the purpose was to examine the effects of ankle dorsiflexion range of motion on forefoot and toe plantar loading during a weighted sled-pushing task. METHODS: Subjects were dichotomized into low dorsiflexion (LD; n=5, height 178.7cm, mass 79.2kg, age 16.8yrs) and high dorsiflexion (HD; n=9, height 175.3cm, mass 79.6kg, age 17.9yrs) range of motion based on the mean value of 8.8cm. Ankle dorsiflexion range of motion was assessed during the standing knee-to-wall test. In-cleat plantar pressure distribution was measured during a weighted (75% of the subject’s body mass) sled-pushing task on a synthetic turf field while wearing standard football cleats. Force time integral was calculated for 9 specific regions and normalized to total foot force time integral. ANOVA (p<0.05) was used to determine the group differences in the relative load for each foot region. Only the forefoot and toe regions were analyzed as those regions had the majority of the total foot loading during the task. RESULTS: Significantly greater relative loading was found under the hallux in subjects who had decreased ankle dorsiflexion range of motion (LD 24.4±6.8%, HD 18.1±3.8%, p=0.044). In contrast, the subjects with greater dorsiflexion range of motion loaded the medial forefoot significantly more (LD 14.3±4.3%, HD 19.7±3.7%, p=0.029). CONCLUSIONS: Greater hallux loading was found during a task that required a large magnitude of MTP joint extension in football players who exhibited decreased ankle dorsiflexion range of motion. Future studies should determine whether interventions aimed at increasing ankle dorsiflexion modify hallux loading. The authors would like to acknowledge funding support from adidas International, Inc.

Functional hallux limitus (FHL) as a potential predisposing factor for anterior knee pain syndrome (AKPS). Results after endoscopic tenolysis of the flexor hallucis longus tendon: A prospective cohort study

Anterior knee pain syndrome (AKPS) is one of the most common musculoskeletal disorders. Functional hallux limitus (FHL) is a loss of metatarsophalangeal joint extension during the second half of the single-support phase. It constitutes a “sagittal plane blockade” attributed to a tendon glide limitation, namely the flexor hallucis longus (FHL) at the level of its retrotalar pulley (tenodesis effect). The aim of our study was to establish a causative relationship between FHL and AKPS and present a new treatment strategy for the AKPS. We prospectively studied a group of patients with AKPS and FHL treated with endoscopic tenolysis of the flexor hallucis longus (FHL) tendon. Inclusion criteria were failed conservative treatment for the AKPS and positive Stretch test for the diagnosis of FHL. Patients with known posture and gait pathology were excluded. Gait analysis performed before and after the operation focused on static, postural and dynamic parameters. Clinical questionnaires were used prospectively pre- and postoperatively. Statistical analysis was performed with SPPS for Mac (P < 0.05). Thirty-five patients were included in our study group (m/f - 39/61%). The mean age was 39-years-old (range 18–69). The patients underwent a posterior hindfoot arthroscopic release of the FHL tendon at the level of its retrotalar pulley, which was dissected. There were no complications encountered postoperatively. All patients did weight bear from day 1. Patellofemoral pain was found in 20% of patients postoperatively as compared to 100% preoperatively (P < 0.05). The area of pressure under the first metatarsal head was statistically significantly increased after the operation (P < 0.05). The average pressure under the tip of the hallux was statistically significantly lower in all patients after the FHL tenolysis. The time of support under the head of the first metatarsal head in dynamic conditions did significantly increase following the operation. (P < 0.05). Based on the Euroqol scores 85% of patients reported very good and excellent results postoperatively (P < 0.05). FHL disrupts the foot stability mechanisms leading to an asynchronous mistimed gait that alters the biomechanics of the lower limb. The substantial static and postural gait favorable changes, highlight the biomechanical importance of the FHL in the etiology of AKPS and also the safety and efficacy of our endoscopic technique pertaining to its treatment. FHL can be considered as a factor implicated in the pathogenesis of AKPS. Arthroscopic release can be considered as an efficacious and safe treatment providing satisfactory results. Additional research studies with larger population groups are warranted.

Sagittal plane blocade chez les patients présentant un hallux limitus fonctionnel (HLF). Résultats après ténolyse endocopique du tendon du long fléchisseur de l’hallux par un modèle multi-segment, une étude comparative et prospective

Functional hallux limitus (Fhl) is a loss of 1st metatarsophalangeal joint extension during the second half of the single-support phase, when the weight-bearing foot is in maximal dorsiflexion, with important consequences during gait. Our objectives were to evaluate the functional results in the sagittal plane biomechanics following the endoscopic release of the Flexor Hallucis Longus (FHL) tendon at the retrotalar pulley, by assessing the kinematics and kinetics of the foot using a multi-segment model. A prospective cohort of 20 patients with FHL was analyzed before and after surgical treatment and compared with 10 healthy subjects comprising the control group. A complete orthopaedic clinical examination was performed. Foot posture was determined with the Foot Posture Index and function before and after surgery was measured with the AOFAS Ankle-Hindfoot and AOFAS Midfoot validated scales. The multi-segment model consisted of Gait and joint angles’ analysis with the use of inertial sensors, plantar pressure analysis and surface electromyography analysis with the use of EMG. Pressure parameters, e.g., peak pressure, maximum force, time of occurrence, and contact time in different foot sub-regions and duration of activation, normalized EMG amplitude, and frequency content of selected muscles of shank were calculated. Results showed an alteration of the gait pattern in the sagittal plane by increasing the flexion moment at the knee and ankle. A diminished dorsal flexion of the great toe at push-off, explaining the failure of the windlass mechanism, was also evident. An alteration of the plantar pressure distribution along the stance phase was associated to a mistimed supination to pronation motion, necessary to gain instability before heel-strike and push-off. FHL causes a sagittal plane blockade, which is usually present at the retrotalar pulley and causes an asynchronic and mistimed gait that changes the biomechanics of the lower limb, especially the foot. Range of motion at the 1st metatarsophalangeal (1MTPJ) joint, ankle and knee joints are comparable to control group values, indicating the restoration of gait biomechanics following the endoscopic release of the FHL. Even though not statistically significant, the existent changes in the angular velocity values of the lower limb, especially below the knee, illustrate the involvement of a delayed muscular activation which is a time dependent factor. Endoscopic FHL release is a safe and promising treatment alternative for 1MTPJ pathologies that restores normal gait and minimizes the occurrence of associated degenerative sequelae. Further studies including larger cohort groups are warranted.

L’Hallux limitus fonctionnel (HLF) comme facteur prédisposant au syndrome rotulien. Résultats après ténolyse endoscopique du tendon du long fléchisseur de l’hallux. Une étude prospective

Anterior knee pain syndrome (AKPS) is one of the most common musculoskeletal disorders. Functional hallux limitus (FHL) is a loss of metatarsophalangeal joint extension during terminal stance and it induces a sagittal plain blockade. The stability mechanisms of the foot are disrupted with consequences especially in the knee. The aim of our study was to establish a causative relationship between FHL and AKPS and present a new treatment strategy for the AKPS. We prospectively studied a group of patients with AKPS and FHL treated with endoscopic tenolysis of the Flexor Hallucis Longus (FHL) tendon. Inclusion criteria were failed conservative treatment for the AKPS and positive Stretch test for the diagnosis of FHL. Patients with known posture and gait pathology were excluded. A matched cohort of patients treated successfully conservatively for AKPS were used as control group. All the patients of the study group had an arthroscopic release of the FHL tendon. Gait analysis performed before and after the operation focused on static, postural and dynamic parameters. Clinical questionnaires were used prospectively pre and postoperatively. Statistical analysis was performed with SPPS for Mac (P < 0.05). Twenty-five patients were included in our study group (m/f – 36/64%). The mean age was 35 years old (range 18–65). There were no complications encountered postoperatively and all the patients were able to weight bear from day 1. Patello-femoral pain was found only in 20% of patients postoperatively as compared to 100% preoperatively (P < 0.05). The area of pressure under the first metatarsal head was statistically significantly increased after the operation (P < 0.05). The average pressure under the tip of the Hallux was statistically significantly lower in all patients after the FHL tenolysis. The time of support under the head of the first metatarsal head in dynamic conditions did significantly increase following the operation. (P < 0.05). Based on the Euroqol scores 85% of patients reported very good and excellent results postoperatively. (P < 0.05). FHL can be considered as a factor implicated in the pathogenesis of AKPS. Static and postural analysis showed a postoperative restoration of the functional anatomy of the forefoot. Postoperative clinical improvement, patient satisfaction and return to previous activities were good and excellent in more than 80%. Arthroscopic release can be considered as an efficacious and safe treatment providing satisfactory results. Additional research studies with larger population groups are warranted.