Plantar Fascia Research Articles

The Impact of Tendon Lengthening Following Achilles Tendon Repair on Foot Kinetics, a Finite Element Analysis

Category: Midfoot/Forefoot; Hindfoot Introduction/Purpose: Triceps surae muscle force is transferred through the Achilles tendon to the calcaneus and from the calcaneus to the plantar fascia and then to the metatarsal heads and the toes which exert force on the ground. Achilles tendon ruptures occur in tendons that have reached a critical point of intrasubstance degeneration. The Achilles tendon almost always heals but frequently lengthens during the healing process, leading to an alteration in the triceps surae force production profile. We hypothesized that Achilles tendon overlengthening has implications not only for force generation but likely has many other impacts throughout the foot. The goal of this work was to evaluate the effect of a lengthened Achilles tendon following tendon repair on the kinetics of the foot. Methods: A validated finite element model of the foot was used to compare foot biomechanics between the foot with a functional and non-functional Achilles tendon. The model of the foot constructed from CT scan images of a female cadaveric foot weighing 60 kg included all 28 bones, 72 ligaments, cartilage, and an encapsulating soft tissue. The model was loaded with 0.5 body weight applied at the center of mass and 0.25 body weight applied to the Achilles tendon simulating quiet stance. The tendon forces were applied using force vectors in the direction of their lines of action. The foot with a non-functional Achilles tendon was created by unloading the Achilles tendon since triceps surae muscle shortening due to tendon lengthening significantly decreases force production. The force transmitted through the joints, force in the ligaments, and plantar pressure were determined for both the foot with a functional and non-functional Achilles tendon. Results: We found that the force transmitted through all the joints decreased when the Achilles tendon force was removed (Figure 1a). In addition, removing the Achilles tendon decreased the force within the plantar fascia, long and short plantar ligaments, and deep deltoid ligament, while it increased the force within the spring and superficial deltoid ligaments (Figure 1b). The plantar fascia experienced the greatest reduction in ligament force after unloading of the Achilles tendon (from 93 N to 26 N). Moreover, the maximum plantar pressure in the heel fat pad increased from 164 kPa to 231 kPa when the Achilles tendon was removed. Conclusion: The varying changes in the force in the ligaments and joints due to Achilles lengthening suggest that Achilles tendon rupture with sequent healing with overlengthening can alter the force distribution throughout the entire foot. A major implication of this work is that in treating Achilles ruptures, an extended period of protection with heel wedges beyond the customary six weeks may be needed to prevent over lengthening of the Achilles. Moreover, this study supports the efficiency of surgical lengthening of the Achilles in the treatment of diabetic forefoot foot ulcers by shifting the plantar pressure towards the calcaneus.

Plantar Fasciitis: An Updated Review.

Plantar fasciitis (PF) is a common musculoskeletal disease. Histologic findings of patients with PF showed mainly chronic degenerative processes rather than inflammation. In addition to mechanical factors, such as repetitive stress and reduced ankle dorsiflexion, PF is also linked to rheumatologic diseases and genetic factors. Ultrasound is becoming a standard imaging technique for assessing PF. Major sonographic findings included increased plantar fascia thickness and hypoechoic plantar fascia. In addition to traditional B-mode ultrasound, sonoelastography can also be utilized to diagnose PF. Ultrasound can also be used to guide therapeutic interventions. Over 80% of patients with PF improved under nonsurgical treatment. Treatment options for PF include physical therapy, modalities (laser, therapeutic ultrasound), extracorporeal shock wave therapy (ESWT), injections, transcatheter arterial embolization, and surgery. For injections, corticosteroid was mostly used in the past but has been replaced gradually by other techniques such as platelet-rich plasma or dextrose prolotherapy. There is also more and more evidence about ESWT in treating PF. Surgery serves as an option for recalcitrant PF cases, and endoscopic fasciotomy seemed to have good outcomes. Ultrasound plays an important role in diagnosing of PF and evaluating the treatment effect, and the use of sonoelastography in addition to traditional B-mode ultrasound may help in the early detection of PF and assessment of the treatment effect.

Tolerability and Safety of Collagenase Clostridium Histolyticum Injection in Participants with Plantar Fibromatosis

Category: Midfoot/Forefoot; Basic Sciences/Biologics Introduction/Purpose: Plantar fibromatosis (PFi) is a functionally disabling disorder characterized by fibrous collagen-containing nodules along the plantar fascia. Collagenase clostridium histolyticum (CCH) is a nonsurgical treatment approved for Dupuytren’s and Peyronie’s disease; both can coexist with PFi. Composed of two collagenases, CCH specifically hydrolyzes certain collagen types and may disrupt the nodule when injected directly. This proof-of-concept study evaluated pharmacokinetics, immunogenicity, and assessed tolerability and safety of CCH treatment of PFi. Methods: In this Phase 1, multicenter study, participants were randomly allocated (1:1:1) to receive 0.6, 1.2, or 2.25 mg/mL CCH. All participants underwent the initial treatment period (ITP) and received 1–2 intralesional injections per nodule on Day 1 with pharmacokinetic samples collected over 24hrs, followed by 5 follow-up visits. Post-ITP, participants with a remaining, palpable nodule could enter the retreatment period (RP) and receive additional CCH doses (at 2.25 mg/mL) with follow-up at specified intervals. Immunogenicity test sampling occurred at screening and at the end of ITP/RP. Adverse events (AEs) were monitored throughout. Results: Twenty-four participants enrolled into ITP, with 11 continuing into RP. Pharmacokinetic and immunogenicity findings were consistent with previous CCH studies in other therapeutic areas. CCH treatment was generally well tolerated, with no serious treatment emergent adverse events (TEAEs), drug discontinuations, or study withdrawals by study end. Over 70% of participants during ITP (19/24) and RP (8/11) reported at least 1 TEAE. Eighty-six TEAEs occurred during ITP and 35 in RP; most were mild in severity (73%, ITP; 83%, RP), and 67% of ITP and 49% of RP TEAEs were treatment related. TEAEs were reportedly injection site- related, with injection site bruising, pain, and swelling frequently recorded. Conclusion: CCH had an expected pharmacokinetics/immunogenicity profile and was safe and well tolerated in participants with PFi. CCH may be a potential nonsurgical intralesional option for PFi treatment.

How Does Lateral Column Lengthening Correct the Flatfoot? A Cadaveric Study

Category: Hindfoot; Basic Sciences/Biologics Introduction/Purpose: Since its description by Evan for correction of overcorrected clubfoot cases, lateral column lengthening ( LCL) has been widely used for correction of pes planovalgus deformity of any etiolog. The main indication is correction of forefoot abduction manifested radiologically as talonavicular uncoverage. It was reported by many authors that LCL improved forefoot abduction and talonavicular uncoverage, but it was also noticed that LCL corrects the flattening of medial longitudinal arch. The mechanism by which LCL corrects the medial longitudinal arch is still not clearly understood. It was also reported that LCL is associated with forefoot supination, but the exact mechanism of supination is not understood. This study aimed to try to understand the mechanism by which LCL changes the shape of the foot. Methods: LCL osteotomy using Hintermann technique was performed in ten fresh frozen below knee cadaveric specimens. After completion of the osteotomy, the talus and leg were removed to monitor how the foot moves under the talus with opening of the osteotomy to change the shape of the foot. The amounts of osteotomy displacement medially, laterally and planetary were observed and measured. After that, the whole plantar skin was removed and plantar ligaments were dissected to study the influence of plantar ligaments on the plane of motion of the osteotomy and the effect of the osteotomy on plantar ligaments. Results: With opening of the osteotomy, the distal portion did not move in pure adduction. Instead, it moved medial and plantar, working as a dorsolateral opening wedge . So, the distal portion was adducted and plantarflexed correcting the forefoot abduction and the flat arch. Because the osteotomy opens dorsally and laterally only, the lateral part of the distal portion was plantar flexed more than the medial part, and this is the cause of forefoot supination. After dissection of plantar ligaments, it was found that the long and short plantar ligaments prevent the osteotomy from opening inferiorly . It was possible to move the distal portion in pure adduction only after cutting the long and short plantar ligaments. Plantar fascia was relaxed after opening of the osteotomy. Conclusion: This mayexplain how the LCL osteotomy corrects the flat medial longitudinal arch and how it causes supination and lateral side overload. Based on this study, Cotton osteotomy should be added to LCL to correct the supination. Also, plantar fascia tightening can not be the cause of medial longitudinal arch correction as it actually becomes more lax after opening of the osteotomy.

PROMIS Scores for Chronic Plantar Fasciitis Before and After Gastrocnemius Recession

Category: Ankle; Hindfoot Introduction/Purpose: There has been an established relationship between increased loading on the Achilles tendon and tension on the plantar fascia. This supports the idea that either tight gastrocnemius and soleus muscles or contractures of the Achilles tendon are risk factors for plantar fasciitis. Gastrocnemius recession has gained popularity as a viable surgical intervention for cases of chronic plantar fasciitis due to isolated gastrocnemius contracture. To our knowledge, this is the first study to investigate PROMIS scores in patients with plantar fasciitis before and after gastrocnemius recession. Methods: The Electronic Medical Record was queried for medical record numbers associated with Current Procedural Terminology code 27687 (gastrocnemius recession). Our study included all patients with a preoperative diagnosis of chronic plantar fasciitis with treatment via isolated gastrocnemius recession with one-year minimum follow-up. 40 patients were included in our study. Patient variables were collected via chart review. Preoperative and postoperative PROMIS scores were collected in the clinic. Results: Preoperative and postoperative PROMIS scores improved for physical function and pain interference from 39.27 and 62.78 to 44.54 and 56.5 (p=0.0005, p=0.0001) respectively, PROIMS Depression scores were not significantly different (p=0.6727). VAS scores significantly decreased from 7.05 to 1.71 (p < 0.0001). Patients with preoperative peripheral neuropathy had significantly lower improvement in PROMIS physical function scores (p=0.0029). Tobacco use led to significantly lower improvement in in PROMIS depression (p=0.0202). Conclusion: Gastrocnemius recession is an effective option for patients with refractory pain in plantar fasciitis. Our PROMIS and VAS data confirm this procedure's utility and highlight its ability to significantly decrease pain and improve physical function in patients with chronic plantar fasciitis. We believe we have added to the literature by incorporating the, inherently superior, PROMIS scores. Based on the results of this study, the authors recommend gastrocnemius recession for patients who fail conservative management for plantar fasciitis.

Efficacy of Collagenase Clostridium Histolyticum Injection, a Potential Nonsurgical Intralesional Treatment Option for Plantar Fibromatosis: A Randomized, Open-Label, Dose-Ranging Study

Category: Midfoot/Forefoot; Basic Sciences/Biologics Introduction/Purpose: Plantar fibromatosis (PFi) is characterized by collagen-containing nodules on the foot along the plantar fascia that can cause pain and functional disability. Current treatments focus on symptom relief, which may become ineffective, or surgery, which can have lengthy recovery times. Collagenase clostridium histolyticum (CCH) is approved for Dupuytren’s and Peyronie’s disease treatment, which are both fibroproliferative disorders that may coexist in patients with PFi. This dose-ranging study assessed the efficacy and safety of CCH treatment of PFi. Methods: In this Phase 1, multicenter study, participants were randomly allocated (1:1:1) to receive 0.6, 1.2, or 2.25 mg/mL CCH. All participants underwent the initial treatment period (ITP) and received 1–2 intralesional injections per nodule on Day 1 with 5 follow-up assessments. Participants with palpable treated nodules could receive additional CCH doses (at 2.25 mg/mL; retreatment period, RP), with follow-up at specified intervals. Assessments included a 5-scale measure of nodule hardness (0 [nonpalpable] to 4 [hard]), and the Foot Function Index-Short Form23 (FFI-SF23) reported as a composite score (0 – 100) of 3 subscale scores (disability, difficulty, and pain subscales). Results: After ITP (n=24), 100% (8/8) of participants receiving 2.25 mg/mL CCH showed improvement in nodule hardness, compared with 87.5% (7/8) and 75% (6/8) of participants receiving 1.2 and 0.6 mg/mL, respectively. FFI-SF23 also showed a negative change from baseline across treatment groups, indicating improvement. Participants that received 2.25 mg/mL reported the largest percent improvement (-83.7%). After RP (n=11), 81.8% (9/11) of participants showed improvement in nodular hardness and an FFI-SF23 score change of -9.3%, indicating further improvement from baseline after ITP. CCH had a consistent safety profile in ITP/RP. Conclusion: CCH caused dose-dependent improvement of nodule hardness after treatment, with 2.25 mg/mL utilized for nodule retreatment; FFI-SF23 scores correlated with this finding, indicating CCH may be a potential nonsurgical intralesional option for PFi treatment.

Treatment Patterns for Plantar Fibromatosis in the United States: A Retrospective Observational Study

Category: Midfoot/Forefoot; Other Introduction/Purpose: Plantar fibromatosis (PF) is a rare disease affecting the plantar aponeurosis, characterized by disordered fibrous tissue and subsequent formation of subcutaneous nodules on the foot/feet. There are no established clinical guidelines for management of PF symptoms, and real-world evidence on treatment patterns among PF patients in the United States (US) is scarce. This retrospective observational study used a comprehensive approach to identify newly diagnosed PF patients and describe subsequent conservative (non-surgical) and surgical treatment patterns. Methods: Patients with evidence of PF from ICD-9/10 diagnosis codes in IQVIA’s PharMetrics® Plus were identified between January 2015-March 2020 and linked to IQVIA’s Ambulatory Electronic Medical Records (AEMR) to confirm diagnosis, using PF- specific SNOMED diagnosis codes or problem name; the earliest evidence of PF was the diagnosis date. Further, eligible patients were required to have continuous enrollment (CE) in a health plan for 12 months before diagnosis (baseline), 24 months of CE after diagnosis (follow-up), evidence of PF ≥30 days after first diagnosis, and age ≥18 years on diagnosis date. Patients with prior diagnosis of PF (through 2014) or other select lower limb conditions during baseline were excluded. Baseline demographic/clinical characteristics and conservative treatment utilization prior to PF diagnosis were assessed. Proportion of patients receiving PF- related conservative and surgical treatment, frequency of use, and time from diagnosis to initiation of first treatment were reported during follow-up. Results: The incident PF cohort (N=620) had mean (SD) age of 52.2(9.9) years and 63.2% were women. Most common baseline comorbidities were thyroid diseases (14.2%), diabetes without complications (12.3%), and smoking (12.3%); 19.0% had evidence of foot or ankle pain/stiffness. During baseline, 53.5% of patients received prescribed analgesic medications (30.6% received opioids). Most patients (91.1%) received conservative treatment after PF diagnosis, including analgesics and physical/occupational therapy (Figure 1A). Among all treatment modalities, time to initiation (months) was shortest for orthotics (median:0.5; IQR:5.5), injectable corticosteroids (median:2.0; IQR:9.2) and prescribed NSAID (median:2.5; IQR:9.1; Figure 1B). Among 42 patients (6.8%) receiving PF-related surgery, conservative treatments were common both before surgery (83.3%; median time from diagnosis to surgery:6.0 months) and after surgery (92.9%). Conclusion: Most newly diagnosed PF patients received conservative treatments within the first 3 months after diagnosis. Analgesic use was high during baseline as well as follow-up. During the 24 months after diagnosis, few patients received surgery and conservative treatment modalities often continued after surgery. Overall, continued and widespread conservative management among PF patients indicates lack of treatment options for PF. Further studies on treatment patterns in US patients aged ≥65 years are needed.

Three-Dimensional Analysis of Windlass Mechanism Using Loading Computed Tomography in Patients With Hallux Rigidus and Healthy Volunteers

Category: Midfoot/Forefoot; Basic Sciences/Biologics Introduction/Purpose: The windlass mechanism (WM) increases the height of the medial longitudinal arch (MLA) of the foot by tensing the plantar aponeurosis during dorsiflexion of the metatarsophalangeal (MTP) joint. We speculated that this mechanism may be deeply involved in the pathogenesis of forefoot diseases such as hallux rigidus (HR). These conditions are three- dimensional (3D) deformities including rotational deformity, but the role of the WM has been evaluated only two-dimensionally by measuring the height of the navicular on lateral plain radiographs. The purpose of this study was to analyze in detail the WM of normal and HR feet in 3D. Methods: Participants were 14 patients with HR (17 feet) and 13 volunteers (21 feet). The volunteers had no history of foot disease or trauma, whereas the patients with HR had Coughlin and Shurnas classification I or II. Computed tomography (CT) of the foot with a load equivalent to the participant’s body weight was performed. Imaging was performed with the 1st MTP joint in the neutral position and dorsiflexed 30 degrees. 3D models were created using the software Mimics Research 17.0. Next, we used the iterative closest point (ICP) algorithm, which allows 3D objects to be superimposed without specifying anatomical feature points. Then, we performed 3D measurements of the (1) rotation of each bone in the MLA with respect to the tibia, (2) rotation of the distal bone in each joint of the MLA, and (3) changes in the height of the geometric center of the navicular. Results: At the calcaneus, navicular and medial cuneiform, the HR group showed less inversion, adduction than healthy group. (P < 0.05) At the talonavicular joint, the navicular was 3.7° inversion, 2.9° adduction in the healthy group and 2.4°inversion, 1.3° adduction in the HR group. At the talocalcaneal joint, the calcaneus was 1.7° inversion, 1.5° adduction in the healthy group and 0.9°inversion, 0.6° adduction in the HR group. In the talonavicular and talocalcaneal joint, the HR group showed less inversion and adduction than control. (P < 0.05) With dorsiflexion of the hallux, the height of the navicular increased by 2.1 mm in the healthy group and 1.3 mm in the HR group. There was a significant difference (P < 0.05) between the two groups. Conclusion: In both groups, the calcaneus, navicular, and medial cuneiform bones moved not only in the sagittal plane but also in the frontal plane. But the movement of the talonavicular and talocalcaneal joints and the change in height of the navicular were significantly reduced compared with the healthy group. In other words, in the HR group, the motion of the midfoot and hindfoot was limited, suggesting that there may be a close relationship between WM dysfunction and midfoot and hindfoot motion. This study indicates that the dysfunction of the WM may have been a clue to the cause of HR.

Musculoskeletal Ultrasound for the Diagnosis of Plantar Fasciitis: An Accuracy and Diagnostic Yield Study.

To evaluate the accuracy of musculoskeletal ultrasound measurement of plantar fascia thickness and shear wave elastography (SWE) calculation of Young's modulus in the diagnosis of plantar fasciitis (PFis), and to explore whether it will have any impact on clinical decision-making, rather than just using established diagnostic methods of clinical symptoms and signs. A diagnostic single-center study was conducted in 60 patients with PFis and 64 patients with other types of heel pain. The sensitivity and specificity of musculoskeletal ultrasound in the diagnosis of PFis were calculated according to the diagnostic criteria for PFis recommended by the Clinical Practice Guide for PFis of the American Physical Therapy Association (APTA) Orthopaedic Branch. The analysis of the receiver operating characteristic curve of the subjects was used to study the accuracy of the diagnosis of PFis by two indicators alone and two indicators jointly. The thickness of plantar fascia measured by musculoskeletal ultrasound and the area under the curve (AUCs) calculated by shear wave elastography for diagnosing PFis were 0.925 and 0.917, respectively, and the optimal cutoff values were 3.15 mm (sensitivity: 100.0%, specificity: 81.3%) and 63.24 kPa (sensitivity: 78.3%, specificity: 92.2%), respectively. The area under the curve (AUCs) for the combined diagnosis of the two is 0.973 (sensitivity: 93.3%, specificity: 93.8%). The thickness of plantar fascia measured by musculoskeletal ultrasound and Young's modulus calculated by SWE have high accuracy in diagnosing PFis, and the combined diagnosis of the two can improve the diagnostic accuracy of patients with PFis.

An ayurvedic management of vatakantak with special reference to plantar fasciitis

Ayurveda - the science of life and longevity - is an ancient Indian system of holistic medicine.Vatakantak can be correlated with Plantar Fasciitis.According to theAyurveda“Vatakantaka” is defined by Acharya Charaka in Charak chikitsa 28 (Vata vyadhi chikitsa adhyaya), by Sushruta in Sushruta Nidan 1 and by Vaagbhata in Vagbhat Nidan15 which is caused by vitiated Vata at Gulfa Sandhi Pradesha(Khudakashrit by Sushruta).Plantar Fasciitis is a chronic inflammation of plantar fascia and degeneration of fibrous tissue with without fibrous formation.Plantar fasciitis is a common cause of foot pain in adults, with the peak incidence occurring in people between the ages of 40 and 60 years, according to the Harrison. A 42-year-old male patient came to outpatient department with chief complaints pain in left heel and foot sole since 1 month.Pain was increased during first few step after waking up from bed. In modern medicine diclofenac sodium introduce by intramuscular, orally can be given for pain management of Plantar Fasciitis. He was treated with Agnikarma (5 seatings at interval of 8days) at local site and Yogaraj Guggulu 500 mg thrice daily for 30 days and Vatavidhwansa Rasa500 mg thrice daily for 30 days. The condition was completely cured without recurrence. Plantar fasciitis can be cured completely without recurrence through Ayurvedic management like Agnikarma with Rajat Shalaka.

Ledderhose's Disease: An Up-to-Date Review of a Rare Non-Malignant Disorder.

Plantar fibromatosis (or Ledderhose's disease) is a rare benign condition, difficult to treat, defined by gradual-growing nodules in the central medial part of the plantar fascia, with the possibility of sclerosis and shrinkage of the entire fascia or, rarely, contractures of the toes. From a histopathological point of view, it is linked to Dupuytren's contracture of the hand and Peyronie's disease of the penis, being part of a large group of fibromatoses, based on a proliferation of collagen and fibroblasts. Its etiology is still not fully understood, even though it has been associated with trauma, diabetes mellitus, use of anticonvulsants, frozen shoulder, alcohol consumption, and liver disease. Typically, ultrasound confirms the diagnosis, and magnetic resonance imaging is used for more aggressive and advanced types. Several conservative treatment techniques, such as steroid injections, verapamil, imatinib, radiation therapy, extracorporeal shock wave therapy, tamoxifen, sorafenib, mitomycin C, and collagenase, have been documented. When non-operative care fails, surgical measures may be considered, even though recurrence is expected. We attempted to provide a better understanding of this disease by covering all of the important aspects: its history, clinical and radiologic findings, diagnosis, pathophysiology features, conservative and surgical treatment, recurrence rate, and prognosis.

Effect of Active Stretching on Reducing Plantaris Fasciitis Pain on Sales Promotion Girl (SPG) Ramayana Makassar Town Square (MTOS)

Objective: to determine the effect of active stretching on reducing plantar fasciitis pain in Sales Promotion Girl (SPG) Ramayana Makassar Town Square (MTOS). Method: a quasi-experimental research design method. This study was carried out with a pretest-posttest design using a control group. The pretest was carried out in both groups, followed by active stretching interventions in the form of Active Calf Stretch and Achilles Tendon Stretch in the experimental group, while the control group was only given intervention in the form of Achilles Tendon Stretch. After that, a posttest was carried out in both groups. The population in this study is the entire SPG in Ramayana MTos. The sample in this study amounted to 60 SPGs which were determined using the Non-probability sampling method where all members of the sample were selected based on predetermined inclusion and exclusion criteria. The collected data were analyzed using the Wilcoxon test. Results: The Wilcoxon Signed Ranks Test showed a p value = 0.001 or a p value <0.05, which means that there is an effect of active stretching exercises on reducing plantar fasciitis pain. Therefore, it can be concluded that there is an effect of active stretching on reducing plantar fascia pain. Conclusion: this study has shown that active stretching exercises significantly reduce plantar fasciitis pain among Sales Promotion Girls (SPGs) at Ramayana Makassar Town Square (MTos). The findings underscore the efficacy of incorporating active stretching interventions to alleviate discomfort in this specific group. Implications of the research: The demonstrated efficacy of active stretching exercises in alleviating plantar fasciitis pain offers a practical solution for enhancing the occupational health and well-being of Sales Promotion Girls (SPGs) and similar professionals. By integrating these exercises into their routines, employers and individuals can potentially mitigate the impact of pain on job performance and overall comfort. Originality/value: This research offers a distinct and original contribution by examining the impact of active stretching exercises specifically on Sales Promotion Girls (SPGs) afflicted with plantar fasciitis pain. The focus on this specific occupational group provides a novel perspective within the context of pain management and occupational health. By investigating the efficacy of active stretching interventions tailored to the needs of SPGs, the research brings a fresh perspective to addressing the unique challenges faced by individuals in roles that involve prolonged standing and walking.

A Bio-Inspired Arched Foot with Individual Toe Joints and Plantar Fascia.

This paper presents the design and testing of an arched foot with several biomimetic features, including five individual MTP (toe) joints, four individual midfoot joints, and plantar fascia. The creation of a triple-arched foot represents a step further in bio-inspired design compared to other published designs. The arched structure creates flexibility that is similar to human feet with a vertical deflection of up to 12 mm. The individual toe joints enable abduction-adduction in the forefoot and therefore a natural pronation motion. Adult female bone data was obtained and converted into a CAD model to accurately identify the location of bones, joints, and arches. An analytical model is presented that gives the relationship between the vertical stiffness and horizontal stiffness of the longitudinal arches and therefore allows the optimization of stiffness elements. Experimental tests have demonstrated a vertical arch stiffness of 76 N/mm which is similar to adult human feet. The range of movement of the foot is similar to human feet with the following values: dorsi-plantarflexion (28°/37°), inversion-eversion (30°/15°), and abduction-adduction (30°/39°). Tests have also demonstrated a three-point contact with the ground that is similar to human feet.

Comparison of different surgical treatments for stage II progressive collapsing foot deformity: a finite element analysis

BackgroundThis study analyzed the advantages and disadvantages of different procedures for stage IIA progressive collapsing foot deformity (PCFD) through three-dimensional finite element models.MethodsA previous validated stage IIA PCFD FEA model was established consisting of 16 bones, 56 ligaments, 5 muscles and soft tissues. The ligament properties of the spring, deltoid, short plantar and long plantar ligaments, and plantar fascia were attenuated according to a previous publication. Medial column fusion (MCF), medializing calcaneal osteotomy (MCO), lateral column lengthening (LCL), and subtalar joint arthroereisis (SJA) operations were simulated in this model. The indexes of plantar stress distribution, maximum von Mises of the medial and lateral columns, strain of the medial ligaments and plantar fascia that supported the medial longitudinal arch, arch height, talo-first metatarsal angle, calcaneus pitch angle, and talonavicular coverage angle were all compared before and after simulated single-foot weight loading.ResultsThe maximum plantar stress of PCFD decreased with MCO and SJA but increased with MCF and LCL. MCF and LCL failed to significantly reduce the stress on the medial column fragments, thereby increasing their stress. Both MCO and SJA relieved medial plantar stress. MCF had no significant effect on stress relief of the medial ligament. MCO, LCL, and SJA were all shown to reduce the pressure on the medial plantar ligament, with LCL having the most obvious effect. All four procedures corrected the arch deformity; however, MCF was not as effective as the other methods. SJA is the best method for restoring arch height and correcting arch deformities. For stage IIA PCFD, isolated MCF failed to reduce pressure on the medial column; however, isolated MCO significantly reduced the pressure on the medial plantar and ligamentous soft tissues while restoring the foot’s arch and correcting the hindfoot valgus.ConclusionSJA with type II sinus tarsi implant effectively transferred pressure from the medial plantar tract to the lateral side and restored the arch. Isolated LCL was not found suitable for stage IIA PCFD.

Larger Achilles and plantar fascia induce lower duty factor during barefoot running

ObjectivesTendons play a crucial role allowing the storage and release of mechanical energy during the running cycle. Running kinematics, including duty factor, constitute a basic element of the runner's biomechanics, and can determine their performance. This study aimed to analyze the link between Achilles tendon and plantar fascia morphology and running parameters, considering the influence of wearing shoes versus running barefoot. DesignCross-sectional study. Methods44 participants (30 men and 14 women) engaged in two running sessions, one with shoes and one without, both lasting 3 min at a consistent speed of 12 km/h. We captured running kinematic data using a photoelectric cell system throughout the sessions. Before the trials, we measured the thickness and cross-sectional area of both the Achilles tendon and plantar fascia using ultrasound. ResultsThe Pearson test revealed a significant correlation (p < 0,05) between Achilles tendon and plantar fascia morphology and contact time (r > −0.325), flight time (r > −0.325) and duty factor (ratio of ground contact to stride time) (r > −0.328) during barefoot running. During the shod condition, no significant correlation was found between connective tissue morphology and kinematic variables. ConclusionsIn barefoot running, greater size of the Achilles tendon and plantar fascia results in a reduced duty factor, attributed to longer flight times and shorter contact times.

Biomechanical Comparison between Rotational Scarf Osteotomy and Translational Scarf Osteotomy: A Finite Element Analysis.

Rotational Scarf osteotomy has its unique advantages in treating hallux valgus, but it also has certain drawbacks. The biomechanical differences between rotational Scarf and translational Scarf osteotomy are not clear evaluates the correction ability and biomechanical difference of two surgical methods for hallux valgus by finite element analysis. The computerized tomography data of a hallux valgus patient were selected to establish a finite element model. The standard Scarf osteotomy was simulated based on the model, and the rotation and translation were performed, respectively. The size of the intermetatarsal angle, contact area, distal metatarsal articular angle and the absolute length of the first metatarsal was compared between the two groups. We completed the cartilage, ligament and other tissues on the bone model to establish a full foot model. We analyzed the troughing, plantar aponeurosis tension, plantar soft tissue, and ground stress and also observed the stability of the fracture site by a three-point bending test. Both surgical methods may effectively correct the intermetatarsal angle. After rotational osteotomy, the contact area increased, and the length of the first metatarsal bone initially increased and then decreased compared to that in the translational group. Furthermore, rotational Scarf significantly increased the distal metatarsal articular angle. Mechanical analysis showed that the cancellous bone in the contact part of the fracture site in the translation group had greater stress, which was the reason for the occurrence of the troughing. Stress distribution of plantar aponeurosis, plantar soft tissue, and the ground showed no significant difference. The three-point bending test showed that the separation of the broken ends of the rotational Scarf osteotomy model (0.133 mm) was slightly smaller than the translational group (0.147 mm). Both surgical methods can successfully correct intermetatarsal angle (IMA). Compared to traditional translational Scarf osteotomy, rotational Scarf osteotomy is more conducive to postoperative stability and healing, but it also has certain drawbacks. In clinical practice, individualized surgical methods still need to be selected for different types of patients with hallux valgus.

A randomized study comparing the effect of platelet-rich plasma and platelet-poor plasma for the treatment of plantar fasciitis

Objective: To verify the effectiveness of therapy with platelet-rich plasma (PRP) in patients with plantar fasciitis, this prospective, longitudinal, double-blind study was carried out. Methodology: Twenty-three participants with chronic plantar fasciitis aged &gt; 20 years, already treated with conventional methods were included. Participants were randomly divided into platelet-poor plasma (PPP) and platelet-rich plasma (PRP) groups. Double centrifugation was carried out to prepare the platelets samples and two millilitres of PPP (supernatant fraction) or PRP (sediment fraction) were mixed with 1mL of 2% calcium gluconate solution and injected in the plantar fascia, as a single dose. A follow-up at 15 days and then every 60 days up to 180 days of application was carried out and a visual analogue scale (VAS) for pain assessment and the quality-of-life scale validated by the American Orthopedic Foot and Ankle Society (AOFAS) were used to measure the outcomes. Results: A reduction in pain (VAS 8 to 4), in both groups, was seen in the first 15 days and remained up to the 6th month after the application of plasmas, however, no difference was observed between the groups. No significant improvement was observed in the quality of life of the patients. Conclusion: PPP or PRP were able to reduce the VAS, but the presence of platelets did not have a role in the pain relief. Other factors in the plasma may play a role in reducing the pain caused by plantar fasciitis for a period of up to 180 days.

Rat Plantar Fascia Stem/Progenitor Cells Showed Lower Expression of Ligament Markers and Higher Pro-Inflammatory Cytokines after Intensive Mechanical Loading or Interleukin-1β Treatment In Vitro.

The pathogenesis of plantar fasciitis is unclear, which hampers the development of an effective treatment. The altered fate of plantar fascia stem/progenitor cells (PFSCs) under overuse-induced inflammation might contribute to the pathogenesis. This study aimed to isolate rat PFSCs and compared their stem cell-related properties with bone marrow stromal cells (BMSCs). The effects of inflammation and intensive mechanical loading on PFSCs' functions were also examined. We showed that plantar fascia-derived cells (PFCs) expressed common MSC surface markers and embryonic stemness markers. They expressed lower Nanog but higher Oct4 and Sox2, proliferated faster and formed more colonies compared to BMSCs. Although PFCs showed higher chondrogenic differentiation potential, they showed low osteogenic and adipogenic differentiation potential upon induction compared to BMSCs. The expression of ligament markers was higher in PFCs than in BMSCs. The isolated PFCs were hence PFSCs. Both IL-1β and intensive mechanical loading suppressed the mRNA expression of ligament markers but increased the expression of inflammatory cytokines and matrix-degrading enzymes in PFSCs. In summary, rat PFSCs were successfully isolated. They had poor multi-lineage differentiation potential compared to BMSCs. Inflammation after overuse altered the fate and inflammatory status of PFSCs, which might lead to poor ligament differentiation of PFSCs and extracellular matrix degeneration. Rat PFSCs can be used as an in vitro model for studying the effects of intensive mechanical loading-induced inflammation on matrix degeneration and erroneous stem/progenitor cell differentiation in plantar fasciitis.

Foot Plantar Pressure Profile Alteration after Microsurgical Great Toe-to-thumb Transfer.

Microsurgical great toe-to-thumb transfer (mGTT) is a widely used procedure when immediate replantation of thumb is not feasible. The aim of this study was to investigate the alteration of plantar pressure profile of the donor foot after mGTT. Twenty patients receiving microsurgical great toe-to-hand transfer between 1985 to 2014, and 16 healthy subjects were recruited. Group 1 consisted of 20 feet receiving mGTT, whereas group 2 consisted of 32 normal feet as control. The flap design in this study was to preserve 1 cm of the proximal phalanx to maintain the attachment of the plantar aponeurosis and intrinsic muscles. The Taiwan Chinese version of the Foot Function Index was used for patient-reported outcome measurement. A novel Emed-X system was used for dynamic plantar pressure measurement. A total of four parameters were collected, including peak pressure, contact area, contact time, and pressure-time integral. In group 1, the peak pressure redistributed under the first metatarsal bone and was significantly higher than group 2 (P < 0.05). There was no significant change of the contact area between the midfoot region of group 1 and group 2 (P > 0.05). Furthermore, similar foot clearance efficiency was demonstrated in group 1 and group 2 (P > 0.05). The windlass effect of the foot will not be affected when performing mGTT with preservation of 1 cm of the proximal phalanx. Therefore, this surgical procedure is highly recommended for clinical application.

Effect of Various Conventional Treatments on Plantar Fasciitis: A Brief Review

Plantar fasciitis is a painful ailment caused by inflammation of the plantar fascia characterised by heel pain. Plantar fasciitis is a degenerative syndrome of the plantar fascia caused by recurrent trauma to the calcaneus. The plantar fascia is a thick, multilayered fibrous connective tissue on the sole of the foot that aids in the creation of the longitudinal arch of the foot. It dynamically stabilises the medial longitudinal arch, restores the arch and helps in reconfiguration of the foot for efficient toe-off. Also, it provides static support to the longitudinal arch as well as dynamic shock absorption. The characteristic PF discomfort is localised around the medial tubercle of the calcaneus and arises after the first few steps in the morning or after a lengthy period of non-weight bearing activities. Standing or walking causes pain and tenderness on the sole of the foot, particularly under the heel. Keywords: plantar fasciitis, heel pain, Muscle stretching exercises, gluteal muscle strengthening