Orthotic treatment for stage I and II posterior tibial tendon dysfunction (flat foot): A systematic review.

OBJECTIVE: To investigate whether orthotic treatment is effective for the treatment of posterior tibial tendon dysfunction stages I and II (flat foot). DATA SOURCES: Five databases (PubMed, Scopus, PEDro, SPORTDiscus and The Cochrane Library) were searched for potential RCTs from their inception until August 2020. REVIEW METHODS: Only randomised controlled trials (RCT) that included subjects diagnosed with posterior tibial dysfunction in the initial stage and treated with orthotic treatments were selected. The outcomes assessed were whatever symptom related to posterior tibial tendon dysfunction stage I and II. Included RCTs were appraised using the Cochrane collaboration risk of bias tool. RESULTS: Four RCT articles and 186 subjects were included. 75% were at high risk of bias for blinding of participants and personnel. Three different types of conservative treatment were used in the studies: foot/ankle-foot orthoses, footwear and stretching /strengthening exercises. Foot orthoses, together with exercise programmes, seemed to improve the effect of orthotic treatment. Foot orthoses with personalised internal longitudinal arch support were more effective than flat insoles or standard treatments in reducing pain. CONCLUSIONS: The use of orthotic treatment may be effective in reducing pain in the early stages of posterior tibial tendon dysfunction. Further research is needed into individualised orthotic treatment and high-intensity monitored exercise programmes.

Effects of a 4-Week Short-Foot Exercise Program on Gait Characteristics in Patients With Stage II Posterior Tibial Tendon Dysfunction.

CONTEXT: Clinically, it has been suggested that increased activation of intrinsic foot muscles may alter the demand of extrinsic muscle activity surrounding the ankle joint in patients with stage II posterior tibial tendon dysfunction. However, there is limited empirical evidence supporting this notion. OBJECTIVE: The purpose of this study was to investigate the effects of a 4-week short-foot exercise (SFE) on biomechanical factors in patients with stage II posterior tibial tendon dysfunction. DESIGN: Single-group pretest-posttest. SETTING: University laboratory. PARTICIPANTS: Fifteen subjects (8 males and 7 females) with stage II posterior tibial tendon dysfunction who had pain in posterior tibial tendon, pronated foot deformity (foot posture index ≥+6), and flexible foot deformity (navicular drop ≥10 mm) were voluntarily recruited. INTERVENTION: All subjects completed a 4-week SFE program (15 repetitions × 5 sets/d and 3 d/wk) of 4 stages (standing with feedback, sitting, double-leg, and one-leg standing position). MAIN OUTCOME MEASURES: Ankle joint kinematics and kinetics and tibialis anterior and fibularis longus muscle activation (% maximum voluntary isometric contraction) during gait were measured before and after SFE program. Cohen d effect size (ES [95% confidence intervals]) was calculated. RESULTS: During the first rocker, tibialis anterior activation decreased at peak plantarflexion (ES = 0.75 [0.01 to 1.49]) and inversion (ES = 0.77 [0.03 to 1.51]) angle. During the second rocker, peak dorsiflexion angle (ES = 0.77 [0.03 to 1.51]) and tibialis anterior activation at peak eversion (ES = 1.57 [0.76 to 2.39]) reduced. During the third rocker, the peak abduction angle (ES = 0.80 [0.06 to 1.54]) and tibialis anterior and fibularis longus activation at peak plantarflexion (ES = 1.34 [0.54 to 2.13]; ES = 1.99 [1.11 to 2.86]) and abduction (ES = 1.29 [0.50 to 2.08]; ES = 1.67 [0.84 to 2.50]) decreased. CONCLUSIONS: Our 4-week SFE program may have positive effects on changing muscle activation patterns for tibialis anterior and fibularis longus muscles, although it could not influence their structural deformity and ankle joint moment. It could produce a potential benefit of decreased tibialis posterior activation.

Sonographic and radiographic findings of posterior tibial tendon dysfunction: a practical step forward.

The purpose of this article is to describe the sonographic and radiographic findings in the diagnosis and treatment of posterior tibial tendon dysfunction. Ultrasound and radiographs play a crucial role in the diagnosis of posterior tibial tendon dysfunction and in imaging the postoperative changes related to posterior tibial tendon dysfunction. Early detection and diagnosis of posterior tibial tendon dysfunction is important in helping to prevent further progression of disease, obviating the need for more invasive and complex procedures.

Correlation between three-dimensional medial longitudinal arch joint complex mobility and medial arch angle in stage II posterior tibial tendon dysfunction.

BACKGROUND: The purpose of this study was to evaluate correlation between three-dimensional medial longitudinal arch joint complex mobility and medial arch angle in stage II posterior tibial tendon dysfunction flatfoot under loading. METHODS: CT scans of 15 healthy feet and 15 feet with stage II posterior tibial tendon dysfunction flatfoot were taken both in non- and simulated weight-bearing condition. The CT images of the hindfoot and medial longitudinal arch bones were reconstructed into three-dimensional models with Mimics and Geomagic reverse engineering software. The three-dimensional complex mobility of each joint in the medial longitudinal arch and their correlation with the medial arch angle change were calculated. RESULTS: From non- to simulated weight-bearing condition, the medial arch angle change and the medial longitudinal arch joints mobility were significant larger in stage II posterior tibial tendon dysfunction flatfoot (p<0.05). The eversion of the talocalcaneal joint, the proximal translation of the calcaneus relative to the talus, the dorsiflexion of the talonavicular joint, the dorsiflexion and abduction of the medial cuneonavicular joint, and the lateral translation of the medial cuneiform relative to the navicular, and the dorsiflexion of the first tarsometatarsal joint were all significantly correlated to the medial arch angle change in stage II posterior tibial tendon dysfunction flatfoot (all r>0.5, p<0.05). CONCLUSIONS: There is increased mobility in the medial longitudinal arch joints in stage II posterior tibial tendon dysfunction flatfoot and the medial arch angle change under loading causes displacement not only at hindfoot joints but also involve midfoot and forefoot joint.

Genetic Influence on Accessory Navicular Bone in the Foot: A Korean Twin and Family Study.

An accessory navicular bone (AN) is the most common accessory ossicle in the foot. The presence of an AN bone can trigger various foot problems, such as posterior tibial tendon pathology, flattening of the medial longitudinal arch, and medial foot pain. Despite the clinical influence of presence of an AN in foot disease, the research regarding its inheritance is still insufficient. A total of 135 pairs of monozygotic (MZ) twins, 25 pairs of dizygotic (DZ) twins, and 676 singletons from families were enrolled in order to estimate genetic influences on AN. After confirmation of zygosity and family relationship with a tandem repeat marker kit and questionnaires, the presence and type of the AN was classified through bilateral feet radiographic examination. The heritability of an AN was estimated using quantitative genetic analysis based on a variance decomposition model considering various types of family relationships: father-offspring pair, mother-offspring pair, and pooled DZ twin and sibling pairs. As a result, approximately 40.96% of the participants in this study had an AN in either foot, with type II being the most common type. The heritability for the presence of any type of an AN in any foot was estimated as 0.88 (95% CI [0.82, 0.94]) after adjusting for age and sex. Specifically, type II AN showed the highest heritability of 0.82 (95% CI [0.71-0.93]). The high heritability of an AN found in this large twin and family study suggests that an AN is determined by the substantial influence of genetic factor.

Influence of tibialis posterior muscle activation on foot anatomy under axial loading: A biomechanical CT human cadaveric study.

BACKGROUND: Collapse of the medial longitudinal arch and subluxation of the subtalar joint are common occurrences in adult flatfoot deformity. Controversy exists about the role of the tibialis posterior (TP) tendon as first and/or essential lesion. Subtle changes in the foot configuration can occur under weight bearing. PURPOSE: This human cadaveric study is designed to investigate the effect that isolated actuation of the TP tendon has on the medial longitudinal arch and the hindfoot configuration under simulated weight bearing. METHODS: A radiolucent frame was developed to apply axial loading on cadaveric lower legs during computer tomography (CT) examinations. Eight pairs of fresh-frozen specimens were imaged in neutral position under foot-flat loading (75N) and under single-leg stance weight bearing (700N) without and with addition of 150N pulling force on the TP tendon. Measurements of subtalar joint subluxation, forefoot arch angle and talo-first metatarsal angle were conducted on each set of CT scans. RESULTS: Subtalar subluxation, talo-first metatarsal angle and talo-navicular coverage angle significantly increased under single-leg stance weight bearing, whereas forefoot arch angle significantly decreased. Actuation of the TP tendon under weight bearing did not restore the forefoot arch angle or correct subtalar subluxation and talo-metatarsal angle. CONCLUSION: Significant effect that weight bearing has on the medial longitudinal arch and the subtalar joint configuration is demonstrated in an ex-vivo model. In absence of other medial column derangement, actuation of the TP tendon alone does not seem to reconstitute the integrity of the medial longitudinal arch or correct the hindfoot subluxation under weight bearing. CLINICAL RELEVANCE: The findings of this study together with the developed model for ex-vivo investigation provide a further insight in foot anatomy.

Posterior tibial tendon transfer improves function for foot drop after knee dislocation.

BACKGROUND: Knee dislocation may be associated with an injury to the common peroneal nerve with a subsequent foot drop. Previous studies have demonstrated good functional results after posterior tibial tendon transfer in patients with foot drop. No studies, to our knowledge, have focused exclusively on knee dislocation as the cause of common peroneal nerve injury leading to foot drop. QUESTIONS/PURPOSES: We determined the percentage of patients developing common peroneal nerve paresis after knee dislocation, the symptom improvement rate in these patients, and patient-reported outcomes (American Orthopaedic Foot and Ankle Society [AOFAS] ankle-hindfoot score), ankle dorsiflexion strength, and ROM in patients with no symptom improvement treated with posterior tibial tendon transfer. METHODS: Two hundred forty-seven patients with knee dislocation, defined as an injury to both the ACL and PCL with an additional injury to the lateral and/or medial ligaments (Schenck Classification II to IV), were registered in a single institution's database between 1996 and 2011. The database was queried for the frequency of documented injuries to the common peroneal nerve and, among those, the frequency of spontaneous resolution after this injury. Patients demonstrating no active dorsiflexion 12 months after injury generally were offered posterior tibial tendon transfer. Postoperatively, patients were evaluated for AOFAS score, ankle dorsiflexion strength, and ROM. RESULTS: Forty-three patients (17%) had a common peroneal nerve paresis at admission. At 1-year followup, 15 of 43 patients (35%) had experienced symptom improvement. One patient experienced spontaneous improvement later than 1 year after injury. One patient was lost to followup. A below-knee amputation was performed in one patient due to the initial trauma. Seven patients were satisfied with their function using a brace or had medical contraindications to surgical treatment, while four patients refused the proposed operation with a tendon transfer, leaving 14 patients treated with posterior tibial tendon transfer. In the 12 patients available for evaluation, mean AOFAS score was 91 of 100. Mean (± SD) dorsiflexion strength was 118 (± 55) Nm on the operated side and 284 (± 94) Nm on the unaffected side (p < 0.001). Mean ROM was 67° (± 15°) on the operated side and 93° (± 14°) on the unaffected side (p < 0.001). CONCLUSIONS: Based on these findings, we recommend posterior tibial tendon transfer for treatment of foot drop that persists at least 1 year after knee dislocation. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Lower limbs biomechanical deficits associated with stage 1 and 2 posterior tibialis tendon dysfunction during walking.

BACKGROUND: Posterior tibialis tendon dysfunction (PTTD) is a chronic degenerative musculoskeletal disorder causing a progressive ankle complex and arch collapse altering lower limb biomechanics. However, biomechanical changes associated with stage 1 and 2 PTTD need to be better characterized during walking to guide clinical recommendations and improve non-operative treatments. RESEARCH QUESTION: What are the lower limb kinematic and kinetic differences between individuals with stage 1 (PTTD1), individuals with stage 2 PTTD (PTTD2) and healthy counterparts during gait? METHODS: Sixteen PTTD1, 11 PTTD2 and 20 healthy controls were included in this multicentric case-control study to compare their lower limb gait biomechanics. Kinematic and kinetic data were recorded using a three-dimensional motion capture system and a force plate. One-dimensional statistical parametric mapping was used to compare lower limb joint motion and moments between groups during the stance phase. RESULTS: PTTD1 had minimal biomechanical differences compared with the control group. In contrast, PTTD2 presented significant differences compared with controls and PTTD1. At the ankle, PTTD2 exhibited greater plantarflexion and eversion angles and midfoot dorsiflexion and inversion angles throughout stance compared with controls and PTTD1. PTTD2 presented lower midfoot abduction moments compared with controls. These changes led PTTD2 to exhibit knee and hip adaptative biomechanical mechanisms in the frontal and transverse planes in late stance. PTTD2 had greater knee internal rotation angles and smaller knee external rotation moments compared to controls. PTTD2 had smaller hip internal rotation angles compared with PTTD1 and smaller hip adduction moments compared with controls. SIGNIFICANCE: PTTD1 showed minimal biomechanical differences compared to controls and important differences compared to PTTD2. The lower limb biomechanical deficits accentuate as the pathology advances from stage 1 to stage 2. PTTD is a progressive condition needing early clinical management at stage 1 to avoid successive biomechanical changes associated with stage 2.

Total and distributed plantar loading in subjects with stage II tibialis posterior tendon dysfunction during terminal stance.

BACKGROUND: In subjects with stage II tibialis posterior tendon dysfunction (TPTD), the function of the tibialis posterior muscle is altered and may be associated with a change in total and distributed loading. METHODS: Thirty subjects with a diagnosis of stage II TPTD and 15 matched control subjects volunteered to participate in a study to examine the total and distributed plantar loading under the foot during the terminal stance phase of gait. Plantar loading, measured as the subject walked barefoot, was assessed using instrumented flexible insoles. A secondary analysis was done to explore the contribution of flatfoot kinematics to plantar loading patterns. RESULTS: Overall, there was reduced total plantar loading in subjects with stage II TPTD compared with controls. Accounting for differences in total loading, the presence of clinically measured weakness in subjects with TPTD was associated with reduced lateral forefoot loading. Medial longitudinal arch height was significantly correlated with loading patterns but explained only 21% of the variance in observed loading patterns. CONCLUSION: Subjects with TPTD who are strong exhibited loading patterns similar to controls. Changes in total and distributed loading during terminal stance suggest there are altered ankle mechanics at push-off during the functional task of gait. CLINICAL RELEVANCE: Strength, in the presence of TPTD, may be important to stabilize the midfoot during gait and might be important in rehabilitation protocols.

Flexor digitorum longus transfer and medial displacement calcaneal osteotomy for the treatment of stage II posterior tibial tendon dysfunction: kinematic and functional results of fifty one feet.

PURPOSE: Stage II posterior tibial tendon dysfunction (PTTD) can be treated by flexor digitorum longus (FDL) tendon transfer and medial displacement calcaneal osteotomy (MDCO). Numerous authors have studied the clinical and radiographic results of this procedure. However, little is known about the kinematic changes. Therefore, the purpose of this study was to assess plantar-pressure distribution in these patients. METHODS: Seventy-three patients with PTTD stage II underwent FDL tendon transfer and MDCO. Plantar pressure distribution and American Orthopaedic Foot and Ankle Society (AOFAS) score were assessed 48 months after surgery. Pedobarographic parameters included lateral and medial force index of the gait line, peak pressure (PP), maximum force (MF), contact area (CA), contact time (CT) and force-time integral (FTI). RESULTS: In the lesser-toe region, PP, MF, CT, FTI and CA were reduced and MF in the forefoot region was increased. These changes were statistically significant. We found statistically significant correlations between AOFAS score and loading parameters of the medial midfoot. CONCLUSIONS: Study results reveal that FDL tendon transfer and MDCO leads to impaired function of the lesser toes during the stance phase. However, there seems to be a compensating increased load in the forefoot region.

Effect of ankle-foot orthotic devices on foot kinematics in Stage II posterior tibial tendon dysfunction.

BACKGROUND: Data are limited on the various orthotic devices available for patients with Stage II posterior tibial tendon dysfunction (PTTD). Foot kinematics observed while walking with an orthotic device are hypothesized to be associated with clinical outcomes and could be used to refine future device designs. METHODS: Fifteen subjects (age, 63.6 ± 6.8 years) with Stage II PTTD walked in the lab under four conditions: (1) shoe only (control condition), (2) shoe with a custom solid AFO (Arizona Co, Mesa, AZ), (3) shoe with a custom articulated AFO (Arizona Co, Mesa, AZ), and (4) shoe with an off-the-shelf AFO (AirLift, DJ Orthopedics). Kinematic data were collected to determine the degree of hindfoot inversion, forefoot plantarflexion (reflective of raising the MLA), and forefoot adduction associated with each condition. RESULTS: The custom articulated device was associated with greater hindfoot inversion compared to the shoe only condition at loading response (p = 0.002), mid-stance (p < 0.001), and terminal stance (p = 0.02). The custom articulated device, custom solid device, and off-the-shelf device were associated with greater forefoot plantarflexion compared to the shoe only condition across all four phases of stance. There were no differences between any of the devices and the shoe condition associated with forefoot adduction. CONCLUSION: The custom devices were associated with greater hindfoot inversion and forefoot plantarflexion compared to walking with only a shoe, while the off-the-shelf device was associated with forefoot plantarflexion but no change in hindfoot motion. None of the devices corrected forefoot abduction compared to the shoe only condition. CLINICAL RELEVANCE: The current biomechanical data may aid in understanding the clinical outcomes seen using these devices as well as provide data to support new designs.

The use of arthrodesis to correct rigid flatfoot deformity.

Rigid adult flatfoot deformity ranges in severity and is caused by a variety of conditions. Treatment is based on the etiology, the severity of symptoms, the stage of the deformity, and patient goals. Posterior tibial tendon pathology, osteoarthritis, posttraumatic arthritis/deformity, inflammatory arthropathy, and neuropathic arthropathy are all known causes of adult flatfoot deformity. Regardless of the cause, treatment goals are the same-restore a plantigrade foot, decrease symptoms, and increase function. When nonsurgical modalities have failed, many surgical reconstructive options are available to restore anatomy and function.

Biomechanical effects of three types of foot orthoses in individuals with posterior tibial tendon dysfunction.

BACKGROUND: Posterior tibial tendon dysfunction (PTTD) is characterized by degeneration of this tendon leading to a flattening of the medial longitudinal arch of the foot. Foot orthoses (FOs) can be used as a treatment option, but their biomechanical effects on individuals with PTTD are not yet fully understood. RESEARCH QUESTION: The aim of this study was to investigate the effects of three types of FOs on gait biomechanics in individuals with PTTD. METHODS: Fourteen individuals were recruited with painful stage 1 or 2 PTTD based on Johnson and Strom's classification. Quantitative gait analysis of the affected limb was performed in four conditions: shoes only (Shoe), prefabricated FO (PFO), neutral custom FO (CFO) and custom varus FO (CVFO) with a 5° medial wedge and a 4 mm medial heel skive. A curve analysis, using 1D statistical parametric mapping, was undertaken to assess differences in lower limb joint motion, joint moments and muscle activity over the stance phase of gait across conditions. RESULTS: Decreased hindfoot eversion angles, decreased ankle inversion moments and increased ankle eversion moments were observed with custom FOs compared to the Shoe and PFO conditions (p < 0.001). CFOs and CVFOs induced an increased knee abduction moment compared to Shoe (p < 0.001). No changes in hip kinematics and kinetics or in EMG activity of tested muscles were observed between conditions. SIGNIFICANCE: Custom orthoses may be more suitable than PFOs to decrease the pathological biomechanical outcomes observed in PTTD. Decreased ankle inversion moments during the stance phase could explain why custom orthoses are effective at reducing pain in PTTD patients. However, clinicians should be careful when prescribing custom orthoses for PTTD since unwanted collateral biomechanical effects can be observed at the knee.

Clinical Tests of Tibialis Posterior Tendinopathy: Are They Reliable, and How Well Are They Reflected in Structural Changes on Imaging?

OBJECTIVE: To determine the reliability of common clinical tests for tibialis posterior tendinopathy (TPT) and to investigate their relationship with grayscale ultrasound findings in individuals who have medial foot/ankle pain. DESIGN: Prospective cohort. METHODS: Fifty-two individuals reporting medial foot/ankle pain were clinically examined by 2 physical therapists using 4 clinical tests for TPT: pain on tendon palpation, swelling around the tendon, pain/weakness with tibialis posterior contraction, and pain during or inability to perform a single-leg heel raise (SLHR). Individuals also underwent an ultrasound examination by a sonographer. Physical therapists and the sonographer were blind to each other's findings. Positive ultrasound examination included at least 1 of the following grayscale changes: hypoechogenicity, fibrillar disruption, or thickening of the tendon. For reliability between the 2 physical therapists, we calculated kappa coefficients and 95% confidence intervals (CIs). To assess relationships between clinical and imaging findings, we calculated odds ratios and 95% CIs. RESULTS: The SLHR was the most reliable test, with substantial agreement between physical therapists (κ = 0.74; 95% CI: 0.54, 0.93), while the other tests had moderate levels of reliability. Of all clinical tests, the SLHR was most related to grayscale findings on ultrasound (odds ratio = 5.8), but was imprecisely so, with a 95% CI of 1.7 to 20.4. CONCLUSION: Of all tests, the SLHR was the most reliable between clinicians and best related to imaging findings in individuals presenting with TPT, aligning with contemporary thinking of tendinopathy as a load-related clinical presentation. There was a disconnect between clinical findings and ultrasound grayscale changes in the tibialis posterior tendon in individuals with TPT. J Orthop Sports Phys Ther 2021;51(5):253-260. Epub 28 Mar 2021. doi:10.2519/jospt.2021.9707.

Correction and prevention of deformity in type II tibialis posterior dysfunction.

UNLABELLED: Cobb described a method of reconstruction in Johnson and Strom Type II tibialis posterior dysfunction (TPD) using a split tibialis anterior musculotendinous graft. We assessed patient function and satisfaction after a modified Cobb reconstruction in a group of patients with a narrow spectrum of dysfunction, examined a modification of the Johnson and Strom classification to emphasize severity of deformity, and assessed the ability of the technique to prevent subsequent fixed deformity. We prospectively followed 32 patients managed by this technique and a translational os calcis osteotomy with early flexible deformity after failed conservative treatment. There were 28 women and four men with unilateral disease. The average followup was 5.1 years. Staging was confirmed clinically and with imaging. The modified surgery involved a bone tunnel in the navicular rather than the medial cuneiform with plaster for 8 weeks followed by orthotics and physiotherapy. All of the osteotomies healed and 29 of the 32 patients could perform a single heel rise test at 12 months. The mean postoperative American Orthopaedic Foot and Ankle Society hindfoot score was 89. One patient had a superficial wound infection and one a temporary dysesthesia of the medial plantar nerve; both resolved. The observations suggest the technique is a comparable method of treating early Johnson and Strom Type II TPD. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Isolated talonavicular arthrodesis in patients with rheumatoid arthritis of the foot and tibialis posterior tendon dysfunction.

BACKGROUND: The foot is often affected in patients with rheumatoid arthritis. Subtalar joints are involved more frequently than ankle joints. Deformities of subtalar joints often lead to painful flatfoot and valgus deformity of the heel. Major contributors to the early development of foot deformities include talonavicular joint destruction and tibialis posterior tendon dysfunction, mainly due to its rupture. METHODS: Between 2002 and 2005 we performed isolated talonavicular arthrodesis in 26 patients; twenty women and six men. Tibialis posterior tendon dysfunction was diagnosed preoperatively by physical examination and by MRI. Talonavicular fusion was achieved via screws in eight patients, memory staples in twelve patients and a combination of screws and memory staples in six cases. The average duration of immobilization after the surgery was four weeks, followed by rehabilitation. Full weight bearing was allowed two to three months after surgery. RESULTS: The mean age of the group at the time of the surgery was 43.6 years. MRI examination revealed a torn tendon in nine cases with no significant destruction of the talonavicular joint seen on X-rays. Mean of postoperative followup was 4.5 years (3 to 7 years). The mean of AOFAS Hindfoot score improved from 48.2 preoperatively to 88.6 points at the last postoperative followup. Eighteen patients had excellent results (none, mild occasional pain), six patients had moderate pain of the foot and two patients had severe pain in evaluation with the score. Complications included superficial wound infections in two patients and a nonunion developed in one case. CONCLUSIONS: Early isolated talonavicular arthrodesis provides excellent pain relief and prevents further progression of the foot deformities in patients with rheumatoid arthritis and tibialis posterior tendon dysfunction.

Deep posterior compartment strength and foot kinematics in subjects with stage II posterior tibial tendon dysfunction.

BACKGROUND: Tibialis posterior muscle weakness has been documented in subjects with Stage II posterior tibial tendon dysfunction (PTTD) but the effect of weakness on foot structure remains unclear. The association between strength and flatfoot kinematics may guide treatment such as the use of strengthening programs targeting the tibialis posterior muscle. MATERIALS AND METHODS: Thirty Stage II PTTD subjects (age; 58.1 +/- 10.5 years, BMI 30.6 +/- 5.4) and 15 matched controls (age; 56.5 +/- 7.7 years, BMI 30.6 +/- 3.6) volunteered for this study. Deep Posterior Compartment strength was measured from both legs of each subject and the strength ratio was used to compare each subject's involved side to their uninvolved side. A 20% deficit was defined, a priori, to define two groups of subjects with PTTD. The strength ratio for each group averaged; 1.06 +/- 0.1 (range 0.87 to 1.36) for controls, 1.06 +/- 0.1 (range, 0.89 to 1.25), for the PTTD strong group, and 0.64 +/- 0.2 (range 0.42 to 0.76) for the PTTD weak group. Across four phases of stance, kinematic measures of flatfoot were compared between the three groups using a two-way mixed effect ANOVA model repeated for each kinematic variable. RESULTS: Subjects with PTTD regardless of group demonstrated significantly greater hindfoot eversion compared to controls. Subjects with PTTD who were weak demonstrated greater hindfoot eversion compared to subjects with PTTD who were strong. For forefoot abduction and MLA angles the differences between groups depended on the phase of stance with significant differences between each group observed at the pre-swing phase of stance. CONCLUSION: Strength was associated with the degree of flatfoot deformity observed during walking, however, flatfoot deformity may also occur without strength deficits. CLINICAL RELEVANCE: Strengthening programs may only partially correct flatfoot kinematics while other clinical interventions such as bracing or surgery may also be indicated.

[Injuries and dysfunction of the posterior tibial tendon]. / Verletzungen und Funktionsstörungen der Tibialis-posterior-Sehne.

The function of the posterior tibial (PT) tendon is to stabilize the hindfoot against valgus and eversion forces. It functions as the primary invertor of the foot and assists the Achilles tendon in plantar flexion. The PT tendon is a stance phase muscle, firing from heel strike to shortly after heel lift-off. It decelerates subtalar joint pronation after heel contact. It functions as a powerful subtalar joint supinator and as a support of the medial longitudinal arch. The action of the tendon travels to the transverse tarsal joints, locking them and allowing the gastrocnemius to support heel rise. Acute injuries of the PT tendon are rare and mostly affect the active middle-aged patient or they are the result of complex injuries to the ankle joint complex. Dysfunction of the PT tendon following degeneration and rupture, in contrast, has shown an increasing incidence in recent years. To which extent changed lifestyle, advancing age, comorbidities, and obesity play a role has not yet been clarified in detail. Dysfunction of the PT tendon results in progressive destabilization of the hind- and midfoot. Clinically, the ongoing deformation of the foot can be classified into four stages: in stage 1, the deformity is distinct and fully correctable; in stage II, the deformity is obvious, but still correctable; in stage III, the deformity has become stiff; and in stage IV, the ankle joint is also involved in the deformity. Treatment modalities depend on stage: while conservative measures may work in stage I, surgical treatment is mandatory for the later stages. Reconstructive surgery is advised in stage II, whereas in stage III and IV correcting and stabilizing arthrodeses are advised. A promising treatment option for stage IV may be adding an ankle prosthesis to a triple arthrodesis, as long as the remaining competence of the deltoid ligament is sufficient. An appropriate treatment is mandatory to avoid further destabilization and deformation of the foot. Failures of treatment result mostly from underestimation of the problem or insufficient treatment of existing instability and deformity.

[Medial displacement calcaneal osteotomy with mini-incision for the treatment of acquired flexible flatfoot caused by posterior tibial tendon dysfunction].

OBJECTIVE: To investigate the clinical outcomes of medial displacement calcaneal osteotomy with mini-incision for the treatment of acquired flexible flatfoot caused by posterior tibial tendon dysfunction. METHODS: From 2005 to 2009, 10 patients (13 feet) of acquired flexible flatfoot with obvious heel valgus underwent medial displacement calcaneal osteotomy with mini-incision. The lateral skin incision of 3.0 - 4.5cm was made to explore the lateral calcaneal wall. Calcaneal osteotomy was performed from inferior and lateral to superior and medial, perpendicular to the longitudinal axis of calcaneal body. The distal segment was displaced medially for 1/3-1/2 width of calcaneal body and fixed by two parallel cannulated screws. All patients were evaluated at 6 weeks, 3 months, 6 months, 12 months and every 6 months pre- and post-operatively by clinical examinations and radiological studies. All patients were physically examined with an extended protocol of questionnaires and the AOFAS Ankle & Hindfoot Scales. The lateral view of full foot allowed an assessment of bone healing, calcaneus inclination angle (CI), talocalcaneal angle (TC) and talar first metatarsal angle (TMT). The AP view of full foot allows assessment of TC and TMT. The heel varus/valgus alignment could be evaluated on the axial radiographs of hindfoot. RESULTS: With a mean postoperative follow-up period of 20.3 months (range 7 - 55 Ms), all patients had bone union as confirmed by clinical examination and radiology. The AOFAS rating scale improved from a pre-operative mean of 50.3 to a mean of 80.2 at 6 months and a mean of 84.2 at last follow-up, without any complication of infection, nerve injure and so on. All radiographic parameters were statistically significant (P < 0.001), including CI, TC and TMT on the lateral view and TC and TMT on the AP view. The heel varus/valgus was corrected on the axial view. CONCLUSION: The medial displacement calcaneal osteotomy with mini-incision is a recommended procedure for the treatment of acquired flexible flatfoot with excellent clinical outcomes, correction of deformity and fewer complications.

Gait alterations in posterior tibial tendonitis: A systematic review and meta-analysis.

BACKGROUND: Posterior tibial tendon dysfunction (PTTD) is a common and debilitating tendinopathy that can lead to a profound decrease in gait function. While the clinical diagnosis and treatment of this disorder are well described, the pathomechanics have not been adequately characterized. The purpose of this systematic review and meta-analysis is to compare foot/ankle kinematics and kinetics in patients with PTTD with healthy controls during gait. METHODS: Relevant articles were selected thought Medline (Pubmed), Scopus, CINAHL, and Web of Science. Studies focused on foot/ankle kinematics and kinetics in patients with PTTD were involved. Articles were included if they: 1) compared patients with PTTD to healthy controls, 2) utilized kinematics or kinetics as the primary outcome measure, 3) evaluated gait tasks, and 4) were written in English. RESULTS: Eleven articles were included in this systematic review, and 8 studies were synthesized and analyzed. Our meta-analyses indicated increased dorsiflexion and abduction of the forefoot, as well as increased plantarflexion and eversion of hindfoot for patients with PTTD during stance of walking. CONCLUSION: Our results from the meta-analysis showed more conclusive changes in the forefoot (increased dorsiflexion and abduction) and hindfoot (increased plantarflexion and eversion) kinematics during stance of walking, which may be associated with a pathological process of PTTD. This review provides an improved understanding of gait function in patients with PTTD and preliminary knowledge for future research.