Flexor Hallucis Longus Research Articles

Resistance training suppresses accumulation of senescent fibro-adipogenic progenitors and senescence-associated secretory phenotype in aging rat skeletal muscle

AbstractAccumulation of senescent cells in tissues contributes to multiple aging-related pathologies. Senescent fibro-adipogenic progenitors (FAPs) contribute to aging-related muscle atrophy. Resistance training can help to maintain skeletal muscle mass, improve mobility, and reduce certain health risks commonly associated with aging. We investigated, using rat model, the impact of resistance training on FAPs in aging skeletal muscle, which remains unclear. Twenty-two-month-old female rats were divided into sedentary and training groups. The training group rodents were trained to climb a ladder while bearing a load for 20 training sessions over 2 months, after which, the flexor hallucis longus muscles were collected and analyzed. Senescent cells were identified using a senescence-associated β-galactosidase stain and p21 immunohistochemistry (IHC), and FAPs were identified using platelet-derived growth factor receptor alpha IHC. The results indicate that resistance training in rats prevented aging-associated skeletal muscle atrophy and suppressed M2 polarization of macrophages. The number of senescent cells was significantly reduced in the 24-month-old training group, with most of them being FAPs. Conversely, the number of senescent FAPs increased significantly in the 24-month-old sedentary group compared with that in the 18-month-old sedentary group. The number of senescent FAPs in the 24-month-old training group decreased significantly. Resistance training also suppressed the senescence-associated secretory phenotype (SASP). The killer T cell-specific marker, CD8α, was elevated in the skeletal muscles of the aging rats following resistance training, indicating upregulation of recognition and elimination of senescent cells. Overall, resistance training suppressed the accumulation of senescent FAPs and acquisition of SASP in aging skeletal muscles.

Comparative Effects of Moderate Intensity Continuous Training and High Intensity Interval Training on Serum Levels of Myonectin in Rats

Background: Myonectin (CTRP15), a recently identified myokine, plays a crucial role in regulating glucose metabolism. Objectives: This study aimed to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on serum myonectin levels, using matched training volumes for both interventions. Methods: Twenty-four male Wistar rats, aged 18 to 20 weeks, were randomly assigned to three groups of eight: Control, MICT, and HIIT. The training groups participated in HIIT and MICT programs (three days per week) on a treadmill for eight weeks. Measurements included serum glucose, insulin, myonectin, and the homeostasis model assessment of insulin resistance (HOMA-IR). Additionally, the weight of the Flexor hallucis longus (FHL), gastrocnemius muscles, and epididymal and retroperitoneal fat pads was recorded. Results: Both HIIT and MICT significantly reduced weight gain and fat mass (epididymal and retroperitoneal) compared to the control group (P < 0.05). Eight weeks of HIIT significantly decreased serum insulin levels and HOMA-IR compared to both the control and MICT groups (P < 0.05). No significant differences in serum myonectin levels were observed between the groups. Conclusions: This study suggests that HIIT is more effective than MICT in improving metabolic status in rats, though it does not significantly affect serum myonectin levels.

Treatment of chronic ruptures and defects of the Achilles tendon

Achilles tendon ruptures that are older than 4-6weeks or developed over amore extended period are chronic. Two challenges characterize the treatment. First, defect zones over alength of several centimeters must frequently be bridged. Second, aprolonged loss of function of the muscles leads to an irreversible fatty degeneration of the tissue. So that even if the tendon is restored, significant functional deficits remain. If there are doubts about the ability of the calf muscles to regenerate, regardless of the size of the defect, tendon transfers are recommended to use the power of an additional muscle to support the plantar flexion of the ankle. Established concepts are the transposition of the flexor hallucis longus or the peroneus brevis muscle. If the muscle is intact, defects of up to 2 cm can be treated with adirect suture. Defects between 2and 5 cm can be bridged using aVY-plasty or aturndown flap. For larger defects, free tendon transplants can be considered. The technical alternative for larger defects is atendon transfer of the flexor hallucis longus or the peroneus brevis muscle. Besides bridging the defect, another advantage of tendon transfer is that vital muscle tissue is placed in the bed of the Achilles tendon. Both tendons are covered with muscle tissue over nearly the full length, which offers advantages, especially in patients with critical soft tissue or after infection. Follow-up treatment is analogous to an acute Achilles tendon rupture. However, permanent impairments are possible; 75-80% of athletes regain their original performance level.

Clinical and biomechanical comparison of suture-external button versus interference screw associated with V-Y advancement or turndown flaps for flexor hallucis longus transfer in chronic Achilles tendon rupture.

Surgical treatment of chronic Achilles tendon rupture is a technically challenging procedure. We aimed to compare the clinical outcomes, range of motion, and strength of ankle plantar- and dorsiflexors between two techniques for fixation of flexor hallucis longus tendon to the calcaneus: interference screw and suture-external button. Twenty-five patients participated in this retrospective comparative study. All patients underwent short harvest FHL tendon transfer for chronic AT rupture were asked for a follow-up visit, at least one year following surgery. The outcomes were evaluated by visual analog scale (VAS), AOFAS ankle-hindfoot score, and VISA-A questionnaire. Ankle ROM with possible restriction in addition to isokinetic strength of ankle plantar- and dorsiflexors was assessed. No statistically significant difference was observed between the groups for pain (P = 0.81), AOFAS ankle-hindfoot scale (P = 0.97), and VISA-A (P = 0.44). Notably, more decrease in ankle dorsiflexion was seen in interference screw group in comparison with suture-external button group (4.4 ± 6.6 vs. 9.5 ± 6.1 degrees, P = 0.06). The difference of active dorsiflexion between operated and non-operated side in interference screw group was statistically significant (P = 0.02). Biotenodesis screw imposed more limb asymmetry in comparison with suture-external button technique. Fixation of transcalcaneal FHL tendon transfer for chronic AT either by interference screw or suture-external button has encouraging postoperative clinical results. Although ROM of the ankle joint reduced in both techniques, interference screw may result in more reduction in dorsiflexion of the ankle.

Weight changes following Achilles debridement with flexor hallucis longus transfer: A retrospective analysis

Obesity poses a growing concern, with global predictions estimating over half the population to be overweight or obese by 2030 (1). While prior research has extensively explored the impact of obesity on hip and knee surgeries, a notable gap persists in understanding weight changes following foot and ankle procedures. This retrospective study focuses on the relationship between Body Mass Index (BMI) and Achilles debridement with flexor hallucis longus (FHL) transfer. Despite prevailing research on the adverse effects of obesity on orthopedic outcomes, few studies examine the reciprocal influence of surgeries on weight. A retrospective analysis of 136 patients undergoing primary Achilles debridement with FHL transfer was conducted. Data encompassing BMI, demographic information, and medical comorbidities were extracted from electronic medical records (EMRs). A clinically meaningful BMI change was considered as a 5 % variation. Inferential statistics in the form of analysis of variance, t-test, and linear regression were employed for data analysis. Among the 136 patients in the study, no statistically significant BMI changes were noted up to two years after surgery (p = 0.9967). While obesity remains a significant factor in foot and ankle surgery complications, our study suggests that Achilles debridement with FHL transfer does not induce significant weight changes. Further research exploring factors influencing weight changes and varying outcomes across demographics is warranted. Level of evidenceIII.

Botulinum toxin as an effective treatment for persistent twitching in first toe: a detailed case study.

Continuous fasciculation that occurs without weakness is referred to as benign fasciculation. Although generally considered non-threatening, cases that persist can significantly impact an individual's quality of life. This study presents a case of a male patient in his 30s experiencing unyielding twitching localized to the sole of his left foot for 2 years. His medical history was devoid of any notable neuromuscular diseases. Results from electromyography testing were also normal for all parameters. Attempts with pharmacological intervention did not yield any improvement of his condition. Although a nerve block targeting the left tibial nerve managed to reduce the severity of the twitching, it failed to decrease its frequency or provide a lasting solution. In search of a more effective treatment, botulinum toxin was administered via ultrasound guidance into the flexor hallucis and digitorum longus muscles. This approach resulted in a marked reduction in both the frequency and severity of the twitching, enabling the patient to resume his daily activities and achieve restful sleep without experiencing any adverse effects. Through this case, the efficacy of botulinum toxin injections as a treatment for intractable twitching is underscored, offering valuable insights into potential therapeutic strategies for similar clinical presentations.

Foot and Ankle MRI Findings in Asymptomatic Professional Ballet Dancers.

Previous research in sport populations has demonstrated that abnormal magnetic resonance imaging (MRI) findings may be present in individuals without symptoms or known pathology. Extending this understanding to ballet, particularly in relation to the foot and ankle, is important to guide medical advice given to dancers. To assess foot and ankle MRI scans in asymptomatic ballet dancers focusing on bone marrow edema and the posterior ankle and to investigate whether these MRI findings would become symptomatic within 1 year. Case series; Level of evidence, 4. In total, 31 healthy dancers (62 feet/ankles; 15 male and 16 female; age, 26.5 ± 4.3 years) who were dancing in full capacity were recruited from an elite professional ballet company. Orthogonal 3-plane short tau inversion recovery imaging of both feet and ankles was obtained using 3T MRI and the images were reviewed using a standardized evaluation form by 2 musculoskeletal radiologists. Injuries in the company were recorded and positive MRI findings were assessed for correlation with any injuries requiring medical attention during the subsequent 12 months. A total of 51 (82%) of the 62 feet and ankles had ≥1 area of bone marrow edema. The most common locations of bone marrow edema were the talus (n = 41; 66%), followed by first metatarsal (n = 14; 23%). Os trigonum and Stieda process were seen in 5 (8%) and 8 (13%) ankles, respectively. Among them, 2 os trigona showed bone marrow edema. Fluid in the anterior and posterior talocrural joints and the subtalar joint was observed in 48%, 63%, and 63% of these joints, respectively. Fluid around foot and ankle tendons was observed, with the most prevalent being the flexor hallucis longus tendon (n = 13; 21%). Two dancers who had positive findings on their MRI subsequently developed symptoms during the next 12 months. Positive MRI findings are commonplace in the foot and ankle of asymptomatic professional ballet dancers. The majority do not result in the development of symptoms requiring medical attention within 12 months. Careful interpretation of MRI findings with the dancer's clinical picture is required before recommending activity modification or further intervention.

Single-Row Repair Versus Double-Row Repair in the Surgical Management of Achilles Insertional Tendinopathy: A Systematic Review.

Approximately 6% of people will report Achilles tendon pain during their lifetime, and one-third of these individuals will have Achilles insertional tendinopathy (AIT). For patients who have failed conservative treatment, surgical repair is performed. Achilles tendon repair can occur through various techniques, including a single-row or double-row repair. To determine if there are significant advantages to double-row repair over single-row repair with respect to biomechanical and clinical outcomes. Systematic review; Level of evidence, 3. A systematic review of the literature was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. An electronic search of the EMBASE and PubMed databases was performed for all studies related to surgical treatment of AIT, which yielded 1431 unique results. These included both biomechanical and clinical studies. Clinical studies in which patients were not diagnosed with AIT, underwent surgery for repair of acute Achilles tendon rupture, or studies that included additional procedures such as a concomitant flexor hallucis longus transfer were excluded. Eligible studies were independently screened by 2 reviewers. A risk-of-bias assessment was conducted using the Cochrane Risk Of Bias In Non-randomized Studies-of Interventions and risk-of-bias tool for randomized trials tools. A total of 23 studies were included, 4 of which were biomechanical studies and 19 were clinical studies. Biomechanical comparison found that there was a significant advantage to using double-row versus single-row fixation with respect to load at yield (354.7 N vs 198.7 N; P = .01) and mean peak load (433.9 N vs 212 N; P = .042). There was no significant difference between double-row and single-row repair with respect to load to failure. Significant heterogeneity of the studies did not allow for a statistical comparison of the clinical outcomes between double-row and single-row repairs. Although biomechanical studies favor double-row repair for AIT, the current data available on the clinical outcomes are not sufficient to determine if there is a clinical advantage of double-row repair. Larger, prospective randomized controlled trials utilizing validated outcome measures are needed to further elucidate whether the biomechanical advantages associated with double-row repair also translate into improved patient-reported outcomes.

Early Functional Outcomes and Complications of Tibial and/or Peroneal Sesamoidectomy Utilizing a Burr Through a Medial Approach.

Sesamoid pathology can lead to significant pain and disability both with activities of daily living and high-impact athletic movements. Sesamoidectomy is a widely used procedure for patients who fail conservative treatment measures. Traditional dorsal or plantar approaches for sesamoidectomy have shown to successfully alleviate pain, but complications were reported. A proposed alternative medial approach using a burr may provide many advantages compared with traditional approaches. This study presents patient outcomes and complications for this technique. This was a retrospective chart review of patients undergoing sesamoidectomy (tibial, peroneal, or both) using a burr through a medial approach to the sesamoid metatarsal articulation. Data collected included patient demographics, radiographic analysis, and outcomes: Veterans Rand 12 Item Health Survey (VR-12), Foot and Ankle Ability Measure (FAAM), visual analog scale (VAS), patient satisfaction, and complications. Twenty-seven patients (29 feet) were included. The mean age was 38.4 years followed up for a mean of 30.9 months. VR-12 physical component improved from 35.98 ± 7.86 to 51.34 ± 8.01 (P < .001), FAAM ADL and sport improved from 58.33 ± 16.61 to 83.27 ± 18.28 (P < .001) and 26.37 ± 20.31 to 63.75 ± 29.74 (P < .001), respectively. Patient satisfaction with the treatment was 80.59% ± 27.06%. The overall complication rate was 11 (37.9%) whereas the overall reoperation rate was 4 (13.7%) of 29 feet. Complications included 1 arthrofibrosis, 1 flexor hallucis longus subacute rupture, and 1 asymptomatic hallux valgus. There were no sesamoid excision revisions. Sesamoidectomy using a medial approach with a burr provided significantly improved short-term functional outcomes, 80% patient satisfaction rate, with a relatively acceptable complications rate including 20% persistent pain. The medial approach is familiar to orthopaedic foot and ankle surgeons, provides adequate exposure, and eliminates the possibility of a painful plantar scar while avoiding disruption of the plantar plate, flexor hallucis brevis tendon, and ligamentous structures attached to the sesamoids. Larger studies with long-term follow-up from other centers are needed.

Anatomical evaluations of the adipose tissue surrounding the flexor hallucis longus tendon

This study aimed to evaluate the presence of adipose tissue surrounding the flexor hallucis longus (FHL) tendon through gross dissection and magnetic resonance imaging (MRI). Grossly, we observed the FHL tendon and surrounding tissues in nine cadavers. Using MRI, we quantitatively evaluated each tissue from the horizontal plane in 40 healthy ankles. Macroscopic autopsy revealed the presence of adipose tissue behind the ankle joint between the FHL and fibula, and horizontal cross-sections showed an oval-shaped adipose tissue surrounding the tendon. The cross-sectional area on MRI was 14.4 mm2 (11.7–16.7) for the FHL tendon and 120.5 mm2 (100.3–149.4) for the adipose tissue. Additionally, the volume of the adipose tissue was 963.3 mm3 (896.2–1115.6). There is an adipose tissue around FHL tendon and maybe this close anatomical relationship might influence the function of the tendon and be involved in its pathologies.

Effects of Rehabilitative Exercise and Neuromuscular Electrical Stimulation on Muscle Morphology and Dynamic Balance in Individuals with Chronic Ankle Instability.

Background and Objectives: Muscle atrophy caused by chronic ankle instability (CAI) can incur muscle weakness, altered movement patterns, and increased risk of injury. Previous studies have investigated the effects of rehabilitative exercises and neuromuscular electrical stimulation (NMES) on characteristics in CAI individuals, but few studies have examined their effects on foot and ankle muscle morphology. This study aimed to determine the effects of rehabilitative exercises and NMES on muscle morphology and dynamic balance in individuals with CAI. Materials and Methods: Participants with CAI (n = 47) were randomly divided into control (CG), rehabilitative exercise (REG), NMES (NG), and rehabilitative exercise and NMES combined (RNG) groups. The six-week intervention program consisting of rehabilitative exercises and NMES was applied to groups excluding CG. Muscle morphology and dynamic balance were evaluated using a portable wireless diagnostic ultrasound device and dynamic balance tests. For statistical analysis, an effect size with 95% confidence interval was calculated to assess mean differences according to intervention. Results: After six weeks, significant increases in morphology and dynamic balance were observed for all muscles except flexor hallucis longus (p > 0.05) in the intervention groups except for CG. However, no significant changes were observed in the CG (p > 0.05). Conclusions: These findings suggest that intervention programs may help prevent muscle atrophy and improve balance in CAI individuals.

Outcomes of Flexor Hallucis Longus Percutaneous Tenotomy for Great Toe Tip Callosity and Ulcers in Patients with Diabetes Mellitus: Cohort Study

Outcomes of Flexor Hallucis Longus Percutaneous Tenotomy for Great Toe Tip Callosity and Ulcers in Patients with Diabetes Mellitus: Cohort Study

Does FHL Tendon Transfer Alter the Outcome of Haglund Deformity Treatment by Using Debridement and Ostectomy in Patients Older Than 50 Years? A Single-Blinded Randomized Controlled Trial.

Chronic Achilles tendinopathy following Haglund disease is a common ankle condition that is difficult to manage. In this study, we will compare the clinical outcomes of debridement and ostectomy with and without FHL tendon transfer in treating Haglund deformity. Forty eligible patients aged >50 years who did not respond to conservative treatment were randomly divided into 2 groups for surgical approach: using flexor hallucis longus (FHL) tendon transfer (FHL group) or "standard procedure" (control group). The main surgical treatment included debridement and ostectomy. AOFAS and VISA-A scores were obtained from all patients pre- and postoperatively. Twenty patients were assigned to each of the 2 groups and were observed for at least 1 year. The American Orthopaedic Foot & Ankle Society (AOFAS) ankle hindfoot scores and the Victorian Institute of Sports Assessment self-administered Achilles (VISA-A) questionnaires scores improved more in the FHL group; however, the average difference in the change in scores did not reach the levels previously reported for minimal clinically important differences. Surgical complications and hallux function were not significantly different between the 2 groups. We found that FHL tendon transfer may improve the clinical outcome scores of Achilles tendon treatment in patients aged >50 years using debridement and ostectomy. However, tendon transfer increases the time of surgery and creates additional skin incisions, which may cause more short-term wound complications, and the significance of the differences in outcome improvement may not be clinically meaningful. Level II, grade A recommendation.

Relationship Between the Flexion Torque of the First Metatarsophalangeal Joint and Intrinsic Foot Muscles Depends on the Ankle Joint Position.

Clinicians and researchers are beginning to pay attention to the importance of the intrinsic foot muscles (IFMs). Among IFMs, the abductor hallucis (AbH) is associated with foot disorders. However, so far no method for assessing the strength of the AbH has been established. In addition, previous studies have shown increased IFM activity in the plantarflexed position of the ankle. Therefore, this study tests the hypothesis that a correlation will be found between the cross-sectional area (CSA) of the AbH and the flexion torque and that the first metatarsophalangeal (MTP) joint would be stronger in the plantarflexed (PF) position of the ankle joint than in the neutral (N) position. Eight male and 8 female patients (16 lower limbs) were included in this study to measure the CSA of IFM and the extrinsic foot muscles of the lower leg. Furthermore, the flexion torque of the first MTP joint was measured using a handheld dynamometer at the N and PF positions of the ankle joint. Correlation analysis was performed to examine the relationship between the CSA of each muscle and the flexion torque of the first MTP joint in the N and PF positions. In the N position, a correlation was found between the flexion torque of the first MTP joint and the CSA of the AbH (r = 0.818), flexor hallucis brevis (r = 0.730), and flexor hallucis longus (r = 0.726). In the PF position, a correlation was found between the flexion torque of the first MTP joint and the CSA of the AbH (r = 0.863) and flexor hallucis brevis (r = 0.680). (P < .05). Overall, this study suggested that by measuring flexion torque of the first MTP joint in the PF position, AbH strength can be estimated without using any expensive equipment. Level V, mechanism-baced reasoning.

Targeted Muscle Reinnervation for a Symptomatic Neuroma in a Traumatic Transmetatarsal Amputee: A Case Report.

An overall healthy 48-year-old man suffered a left foot mangled crush injury resulting in a post-transmetatarsal amputation and subsequently developing a painful neuroma on the plantar surface of the foot. To avoid the zone of injury, targeted muscle reinnervation was used to treat the neuroma by coapting the tibial nerve to the motor point of the flexor hallucis longus (FHL) muscle. At 1-year follow-up, the patient reported no pain at rest, returned to work, and could ambulate with an orthosis for 30 minutes. Rare tibial nerve coaptations to the FHL could serve as a treatment option for patients with neuromas in traumatic postmetatarsal amputation.

Talocalcaneal Coalition Resection with Local Fat Grafting and Flatfoot Reconstruction.

Talocalcaneal (TC) coalitions typically present in the pediatric population with medial hindfoot and/or ankle pain and absent subtalar range of motion. Coalition resection with fat interposition is well described for isolated tarsal coalitions1,2; however, patients with concomitant rigid flatfoot may benefit from additional reconstructive procedures. To address this, we employ the surgical technique of TC resection with local fat grafting and flatfoot reconstruction. This procedure is described in 3 steps: (1) gastrocnemius recession and fat harvesting, (2) TC coalition resection with local fat interposition, and (3) peroneus brevis Z-lengthening and calcaneal lateral column lengthening osteotomy with allograft. A 3 to 4-cm posteromedial longitudinal incision is made at the distal extent of the medial head of the gastrocnemius muscle. The gastrocnemius tendon is identified, dissected free of surrounding tissue, and transected. Superficial fat is then harvested from this incision before wound closure. A 7-cm incision is made from the posterior aspect of the medial malleolus to the talonavicular joint. The neurovascular bundle and flexor tendons are dissected carefully from the surrounding tissue as a group and protected while the coalition is completely resected, and bone wax and the local fat are utilized at the resection site to prevent regrowth of the coalition. An approximately 7-cm incision is then made laterally and obliquely following the Langer lines and centered over the lateral calcaneus. The peroneal tendons are released from their sheaths, and the peroneus brevis is Z-lengthened. A calcaneal osteotomy is performed about 1.5 cm proximal to the calcaneocuboid joint and angled to avoid the anterior and middle subtalar facet joints. Two Kirschner wires are inserted retrograde across the calcaneocuboid joint, and the calcaneal osteotomy is opened. A trapezoid-shaped allograft bone wedge is impacted, and the Kirschner wires are advanced across into the calcaneus. The lengthened peroneus brevis tendon is repaired, and the wound is closed in a layered fashion. First-line treatment is nonoperative with orthotics and immobilization. Surgical options include coalition resection with or without calcaneal lengthening osteotomy, arthrodesis, or arthroereisis. Following coalition resection, various grafts can be utilized, including fat autografts, bone wax, or split flexor hallucis longus tendon3-6. This procedure addresses TC coalition with concomitant rigid flatfoot. Resection alone may increase subtalar motion but does not correct a flatfoot deformity. Historically, surgeons performed arthrodesis or arthroereisis, but these are rarely performed in young patients. In patients with coalitions involving >50% of the posterior facet or preexisting degenerative changes, arthrodesis may be indicated7. Patients can expect improvement in pain and function8-11. Previous investigators reported improved patient satisfaction, improved range of motion, clinical and radiographic hindfoot correction, and an improved American Orthopaedic Foot & Ankle Society hindfoot score at the time of final follow-up8,9. Carefully free the neurovascular bundle from the surrounding soft tissue so that it can be carefully retracted away from the area of coalition resection.Utilize the interval between the posterior tibialis and flexor digitorum longus tendons to approach the coalition.Expose the medial wall of the coalition and perform a careful resection that avoids inadvertently diverging into the body of the talus or calcaneus.Place a smooth lamina spreader into the resected area and gently open the subtalar joint to confirm complete coalition resection.Place 2 retrograde wires across the calcaneocuboid joint before performing the osteotomy. Without this step, up to 50% of cases experience calcaneocuboid subluxation and/or rotation after the lateral column lengthening12.To determine the size of the allograft, place a lamina spreader into the osteotomy site to measure the width.If present, rigid supination of the forefoot must be corrected with a medial cuneiform plantar-based closing osteotomy. AOFAS = American Orthopaedic Foot & Ankle SocietyFADI = Foot and Ankle Disability IndexMRI = magnetic resonance imagingCT = computed tomographyOR = operating roomK-wire = Kirschner wire.

The Biomechanical, Biochemical, and Morphological Properties of 19 Human Cadaveric Lower Limb Tendons and Ligaments: An Open-Access Data Set

Background: Methodological heterogeneity hinders data comparisons across isolated studies of tendon and ligament properties, limiting clinical understanding and affecting the development and evaluation of replacement materials. Purpose: To create an open-access data set on the morphological, biomechanical, and biochemical properties of clinically important tendons and ligaments of the lower limb, using consistent methodologies, to enable direct tendon/ligament comparisons. Study Design: Descriptive laboratory study. Methods: Nineteen distinct lower limb tendons and ligaments were retrieved from 8 fresh-frozen human cadavers (5 male, 3 female; aged 49-65 years) including Achilles, tibialis posterior, tibialis anterior, fibularis (peroneus) longus, fibularis (peroneus) brevis, flexor hallucis longus, extensor hallucis longus, plantaris, flexor digitorum longus, quadriceps, patellar, semitendinosus, and gracilis tendons; anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments; and 10 mm–wide grafts from the contralateral quadriceps and patellar tendons. Outcomes included morphology (tissue length, ultrasound-quantified cross-sectional area [CSAUS], and major and minor axes), biomechanics (failure load, ultimate tensile strength [UTS], failure strain, and elastic modulus), and biochemistry (sulfated glycosaminoglycan [sGAG] and hydroxyproline contents). Tissue differences were analyzed using mixed-model regression. Results: There was a range of similarities and differences between tendons and ligaments across outcomes. A key finding relating to potential graft tissue suitability was the comparable failure loads, UTS, CSAUS, sGAG, and hydroxyproline present between hamstring tendons (a standard graft source) and 5 tendons not typically used for grafting: fibularis (peroneus) longus and brevis, flexor and extensor hallucis longus, and flexor digitorum longus tendons. Conclusion: This study of lower limb tendons and ligaments has enabled direct comparison of morphological, biomechanical, and biochemical human tissue properties—key factors in the selection of suitable graft tissues. This analysis has identified 6 potential new donor tissues with properties comparable to currently used grafts. Clinical Relevance: This extensive data set reduces the need to utilize data from incompatible sources, which may aid surgical decisions (eg, evidence to expand the range of tendons considered suitable for use as grafts) and may provide congruent design inputs for new biomaterials and computational models. The complete data set has been provided to facilitate further investigations, with the capacity to expand the resource to include additional outcomes and tissues.

Effects of technological running shoes versus barefoot running on the intrinsic foot muscles, ankle mobility, and dynamic control: a novel cross-sectional research

BackgroundTechnological running shoes have become increasingly popular, leading to improvements in performance. However, their long-term effects on foot musculature and joint mobility have not been thoroughly studied. ObjectiveTo compare the activation of the intrinsic foot muscles between runners wearing technological footwear and barefoot runners. Secondary objectives included assessing ankle dorsiflexion (DF) range of motion (ROM) and dynamic postural control in both groups. MethodsA cross-sectional study was conducted involving 22 technological footwear runners and 22 barefoot runners. Ultrasonography was used to measure the thickness of the plantar fascia (PF) and the quadratus plantae (QP), abductor digiti minimus (ADM), abductor hallucis (AH), and flexor hallucis longus (FHL) muscles. Ankle mobility and dynamic postural control were also recorded. ResultsUltrasonography measurements showed statistically significant differences for PF thickness (mean difference [MD]: -0.10 cm; 95% CI: -0.13, -0.05 cm), QP cross-sectional area (CSA) (MD: -0.45 cm2; 95% CI: -0.77, -0.12 cm2), ADM CSA (MD: -0.49 cm2; 95% CI: -0.70, -0.17 cm2), and FHL thickness (MD: 0.82 cm; 95% CI: 0.53, 1.09 cm), with all measurements being lower in the group wearing technological footwear compared to the barefoot runners. Ankle DF ROM was also significantly greater for the barefoot runners (MD: -5.1°; 95% CI: -8.6, -1.7°). ConclusionsThese findings suggest potential implications for the foot musculature and ankle mobility in runners using technological footwear.

Differences in muscle activity of extrinsic and intrinsic foot muscles in toe grip and push-down movements of the great toe

Toe flexor strength is generated primarily by the flexor hallucis longus (FHL) of the extrinsic foot muscles (EFMs) and the plantar intrinsic foot muscles (PIFMs) of the great toe. Toe flexion methods can be broadly classified into toe grip (TG) and toe push-down (TP). Additionally, TP's interphalangeal joint (IPJ) position may influence the FHL and PIFMs activity ratios. This study aimed to elucidate the differences in the muscle activity and muscle activity ratios of the FHL and AbdH during TG, TP with IPJ flexion (TPIF), and TP with IPJ extension (TPIE).Surface electromyography and a custom-made instrument were used to measure the FHL and AbdH muscle activity during TG, TPIF, and TPIE of the great toe in 28 healthy men. The muscle activity and AbdH/FHL muscle activity ratio in the three conditions were statistically compared.The FHL activity was significantly higher during TG and TPIF than during TPIE. The AbdH muscle activity was significantly higher during TPIF and TPIE than that during TG. The AbdH/FHL muscle activity ratio was significantly higher for TPIE, TPIF, and TG in that order.This study showed that the FHL and AbdH muscle activity differed depending on the TG and TP of the great toe, and that the AbdH/FHL muscle activity ratio was different in the IPJ position. These results suggest that selecting a toe flexion method according to the target muscle when measuring and training the great toe flexor strength is important.

Comparative Study of Degree of Great Toe Movement after Complete and Partial Flexor Hallucis Longus Harvest in Free Fibula Flap.

Background The flexor hallucis longus (FHL) muscle is crucial in fine motor control of the great toe but the muscle is often sacrificed in free fibula flap (FFF) reconstruction. The aim of this study was to compare great toe movement between complete and partial FHL resection during FFF harvest to see if FHL can be left behind (without undergoing fibrosis) in situ when bulk is not required at the recipient site. Methods A prospective, cross-sectional, observational study was performed including patients undergoing FFF harvest over a 2-year period. Movement of great toe interphalangeal joint was recorded of operated and unoperated legs in patients undergoing partial and complete FHL harvest and data analyzed. Results There was a statistically significant ( p < 0.05) difference between the two groups of patients. Conclusion FHL can be safely left in situ in patients not requiring bulk at the recipient site as blood supply, nerve supply, and muscle function are not compromised in partial FHL harvest. Further image-based and dye-based studies are warranted.