Recommendation:
The historical nomenclature for the adult acquired flatfoot deformity (AAFD) is confusing, at times called posterior tibial tendon dysfunction (PTTD), the adult flexible flatfoot ...deformity, posterior tibial tendon rupture, peritalar instability and peritalar subluxation (PTS), and progressive talipes equinovalgus. Many but not all of these deformities are associated with a rupture of the posterior tibial tendon (PTT), and some of these are associated with deformities either primarily or secondarily in the midfoot or ankle. There is similar inconsistency with the use of classification schemata for these deformities, and from the first introduced by Johnson and Strom (1989), and then modified by Myerson (1997), there have been many attempts to provide a more comprehensive classification system. However, although these newer more complete classification systems have addressed some of the anatomic variations of deformities encountered, none of the above have ever been validated. The proposed system better incorporates the most recent data and understanding of the condition and better allows for standardization of reporting. In light of this information, the consensus group proposes the adoption of the nomenclature “Progressive Collapsing Foot Deformity” (PCFD) and a new classification system aiming at summarizing recent data published on the subject and to standardize data reporting regarding this complex 3-dimensional deformity.
Level of Evidence:
Level V, consensus, expert opinion.
Consensus Statements Voted:
CONSENSUS STATEMENT ONE: We will rename the condition to Progressive Collapsing Foot Deformity (PCFD), a complex 3-dimensional deformity with varying degrees of hindfoot valgus, forefoot abduction, and midfoot varus.
Delegate vote: agree, 100% (9/9); disagree, 0%; abstain, 0%.
(Unanimous, strongest consensus)
CONSENSUS STATEMENT TWO: Our current classification systems are incomplete or outdated.
Delegate vote: agree, 100% (9/9); disagree, 0%; abstain, 0%.
(Unanimous, strongest consensus)
CONSENSUS STATEMENT THREE: MRI findings should be part of a new classification system.
Delegate vote: agree, 33% (3/9); disagree, 67% (6/9); abstain, 0%.
(Weak negative consensus)
CONSENSUS STATEMENT FOUR: Weightbearing CT (WBCT) findings should be part of a new classification system.
Delegate vote: agree, 56% (5/9); disagree, 44% (4/9); abstain, 0%.
(Weak consensus)
CONSENSUS STATEMENT FIVE: A new classification system is proposed and should be used to stage the deformity clinically and to define treatment.
Delegate vote: agree, 89% (8/9); abstain, 11% (1/9).
(Strong consensus)
The rate of total ankle arthroplasty (TAA) is increasing relative to ankle arthrodesis (AA) for patients seeking surgical treatment for end-stage ankle arthritis. Patients and providers would benefit ...from a more complete understanding of the rate of improvement, the average length of time to achieve maximal function and minimal pain, and whether there is a greater decline in function or an increase in pain over time following TAA compared with AA. The objectives of this study were to compare treatment changes in overall physical and mental function and ankle-specific function, as well as pain intensity at 48 months after TAA or AA in order to determine if the improvements are sustained.
This was a multisite prospective cohort study that included 517 participants (414 TAA and 103 AA) who presented for surgical treatment. Participants were compared 48 months after surgery using the Foot and Ankle Ability Measure (FAAM) Activities of Daily Living and Sports subscales (0 to 100 points), the Short Form-36 (SF-36) Physical and Mental Component Summary (PCS and MCS) scores (0 to 100 points), and pain scores (0 to 10 points).
Both groups achieved significant improvement in the 2 FAAM measures, the SF-36 PCS score, and all of the pain measures at 48 months after surgey (p < 0.001). Mean improvements from baseline in patients undergoing TAA for the FAAM Activities of Daily Living, FAAM Sports, and SF-36 scores were at least 9 points, 8 points, and 3.5 points, respectively, which were higher than in those undergoing AA. Mean improvements in worst and average pain were at least 0.9 point higher in patients undergoing TAA than in those undergoing AA at 12, 24, and 36 months. These differences were attenuated by 48 months. For both treatments, all improvements from baseline to 24 months had been maintained at 48 months.
When both procedures are performed by the same group of surgeons, patients who undergo TAA or AA for end-stage ankle arthritis have significant improvement in overall function, ankle-specific function, and pain at 48 months after surgery, with better functional improvement in the TAA group.
Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
The best treatment for displaced, intraarticular fractures of the calcaneum remains controversial. Surgical treatment of these injuries is challenging and have a considerable learning curve. Studies ...comparing operative with nonoperative treatment including randomized trials and meta-analyses are fraught with a considerable number of confounders including highly variable fracture patterns, soft-tissue conditions, patient characteristics, surgeon experience, limited sensitivity of outcome measures, and rehabilitation protocols. It has become apparent that there is no single treatment that is suitable for all calcaneal fractures. Treatment should be tailored to the individual fracture pathoanatomy, accompanying soft-tissue damage, associated injuries, functional demand, and comorbidities of the patient. If operative treatment is chosen, reconstruction of the overall shape of the calcaneum and joint surfaces are of utmost importance to obtain a good functional result. Despite meticulous reconstruction, primary cartilage damage due to the impact at the time of injury may lead to posttraumatic subtalar arthritis. Even if subtalar fusion becomes necessary, patients benefit from primary anatomical reconstruction of the hindfoot geometry because
in situ
fusion is easier to perform and associated with better results than corrective fusion for hindfoot deformities in malunited calcaneal fractures. To minimize wound healing problems and stiffness due to scar formation after open reduction and internal fixation (ORIF) through extensile approaches several percutaneous and less invasive procedures through a direct approach over the sinus tarsi have successfully lowered the rates of infections and wound complications while ensuring exact anatomic reduction. There is evidence from multiple studies that malunited displaced calcaneal fractures result in painful arthritis and disabling, three-dimensional foot deformities for the affected patients. The poorest treatment results are reported after open surgical treatment that failed to achieve anatomic reconstruction of the calcaneum and its joints, thus combining the disadvantages of operative and nonoperative treatment. The crucial question, therefore, is not only whether to operate or not but also when and how to operate on calcaneal fractures if surgery is decided.
Weightbearing radiographs are widely used to investigate foot disorders. However, it is unclear how imaging during partial weightbearing affects foot alignment measurements. This study aimed to ...determine a partial weightbearing threshold that yields consistent measurements of various radiographic angles. Eighteen normal fresh‐frozen cadaveric foot specimens were dissected and prepared for mechanical testing using a custom‐designed, computed tomography‐compatible loading frame. Specimens were placed in a neutral ankle position and scanned in five axial loading conditions (0%, 12.5%, 25%, 37.5%, and 50% bodyweight) using weightbearing computed tomography. (Note 50% bodyweight per foot represents full bodyweight in quiet stance.) The lateral first talometatarsal and calcaneal pitch angles were measured on lateral radiographic projections, and the hallux valgus angle and first−second, fourth−fifth, and first−fifth intermetatarsal angles were measured on axial projection images. The lateral first talometatarsal angle decreased significantly with increased bodyweight loading (p < 0.01). Mean significant decreases in the lateral first talometatarsal angle compared to 0% were 6.6° for 12.5%, 7.6° for 25%, 8.8° for 37.5%, and 10.0° for 50% bodyweight loading; 12.5% to 50% was also significant. There was no significant differences between other loading condition pairings or with increased axial load at other angles. The medial longitudinal arch flattened with increasing axial load, resulting in a decreased lateral first talometatarsal angle. However, this radiographic parameter did not change between the 25% and 50% bodyweight conditions, indicating that partial weightbearing imaging (between 12.5% and 25% bodyweight) might be enough to reproduce the sagittal foot alignments observed under full weightbearing conditions in normal feet.
BACKGROUND:Newer designs and techniques of total ankle arthroplasty (TAA) have challenged the assumption of ankle arthrodesis (AA) as the primary treatment for end-stage ankle arthritis. The ...objective of this study was to compare physical and mental function, ankle-specific function, pain intensity, and rates of revision surgery and minor complications between these 2 procedures and to explore heterogeneous treatment effects due to age, body mass index (BMI), patient sex, comorbidities, and employment on patients treated by 1 of these 2 methods.
METHODS:This was a multisite prospective cohort study comparing outcomes of surgical treatment of ankle arthritis. Subjects who presented after nonoperative management had failed received either TAA or AA using standard-of-treatment care and rehabilitation. Outcomes included the Foot and Ankle Ability Measure (FAAM), Short Form-36 (SF-36) Physical and Mental Component Summary (PCS and MCS) scores, pain, ankle-related adverse events, and treatment success.
RESULTS:Five hundred and seventeen participants underwent surgery and completed a baseline assessment. At 24 months, the mean improvement in FAAM activities of daily living (ADL) and SF-36 PCS scores was significantly greater in the TAA group than in the AA group, with a difference between groups of 9 points (95% confidence interval CI = 3, 15) and 4 points (95% CI = 1, 7), respectively. The crude incidence risks of revision surgery and complications were greater in the AA group; however, these differences were no longer significant after adjusting for age, sex, BMI, and Functional Comorbidity Index (FCI). The treatment success rate was greater after TAA than after AA for those with an FCI of 4 (80% versus 62%) and not fully employed (81% versus 58%) but similar for those with an FCI score of 2 (81% versus 77%) and full-time employment (79% versus 78%).
CONCLUSIONS:At 2-year follow-up, both AA and TAA were effective. Improvement in several patient-reported outcomes was greater after TAA than after AA, without a significant difference in the rates of revision surgery and complications.
LEVEL OF EVIDENCE:Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
Background:
Patients with adult-acquired flatfoot deformity (AAFD) develop peritalar subluxation, which may stem from valgus inclination of the inferior surface of the talus. We hypothesized that ...patients with AAFD would have an increased valgus tilt of the subtalar joint in the coronal plane compared to controls when assessed with a novel multiplanar weight-bearing imaging (MP-WB).
Methods:
Eighteen normal and 36 stage II AAFD patients scheduled to undergo operative reconstruction were evaluated by MP-WB through measuring 3 novel angles of the subtalar joint in the coronal view: (1) angle between inferior facet of the talus and the horizontal/floor (inftal-hor), (2) angle between inferior and superior facets of the talus (inftal-suptal), and (3) angle between inferior facet of the talus and superior facet of the calcaneus (inftal-supcal). Intra- and interobserver reliability were evaluated via intraclass correlation coefficients (ICCs). Differences in angles between AAFD patients and controls were evaluated using Wilcoxon rank-sum test.
Results:
Intra- and interobserver reliability were excellent for inftal-hor (ICC .942 and .991, respectively) and inftal-suptal (ICC .948 and .989, respectively), and moderate-good for inftal-supcal (ICC .604 and .742, respectively). Inftal-hor and inftal-suptal angles were found to be significantly greater in AAFD patients (P < 0.001) at all 3 locations along the posterior subtalar joint, while inftal-supcal did not demonstrate a significant difference (P = .741). While controls exhibited varus orientation at the anterior aspect of the joint, AAFD patients maintained a valgus orientation throughout.
Conclusion:
Inftal-hor and inftal-suptal angles provided a reliable means of evaluating the orientation of the subtalar joint axis in AAFD via MP-WB, and showed that the subtalar joint had increased valgus orientation in AAFD compared to controls. This may allow for identification of patients at risk for developing AAFD, and could potentially be used in guiding operative reconstruction.
Level of Evidence:
Level III, comparative series.
Acute and chronic subtalar instability and commonly coexistent with other hindfoot pathology but can be difficult to diagnose. A high degree of clinical suspicion is required as most imaging ...modalities and clinical maneuvers are poor at detecting isolated subtalar instability. The initial treatment is similar to ankle instability, and a wide variety of operative interventions have been presented in the literature for persistent instability. Outcomes are variable and limited.
Multi-segment foot models (MFMs) provide a better understanding of the intricate biomechanics of the foot, yet it is unclear if they accurately differentiate foot type function during locomotion.
We ...employed an MFM to detect subtle kinematic differences between foot types, including: pes cavus, neutrally aligned, and asymptomatic and symptomatic pes planus. The study investigates how variable the results of this MFM are and if it can detect kinematic differences between pathologic and non-pathologic foot types during the stance phase of gait.
Independently, three raters instrumented three subjects on three days to assess variability. In a separate cohort, each foot type was statically quantified for ten subjects per group. Each subject walked while instrumented with a four-segment foot model to assess static alignment and foot motion during the stance phase of gait. Statistical analysis performed with a linear mixed effects regression.
Model variability was highest for between-day and lowest for between–rater, with all variability measures being within the true sample variance. Almost all static measures (radiographic, digital scan, and kinematic markers) differed significantly by foot type. Sagittal hindfoot to leg and forefoot to leg kinematics differed between foot types during late stance, as well as coronal hallux to forefoot range of motion. The MFM had low between-rater variability and may be suitable for multiple raters to apply to a single study sample without introducing significant error. The model, however, only detected a few dynamic differences, with the most dramatic being the hallux to forefoot coronal plane range of motion.
Significance: Results only somewhat aligned with previous work. It remains unclear if the MFM is sensitive enough to accurately detect different motion between foot types (pathologic and non-pathologic). A more accurate method of tracking foot bone motion (e.g., biplane fluoroscopy) may be needed to address this question.
•The majority of static measures differed significantly by foot type.•Sagittal hind- and forefoot to leg kinematics differed between groups during stance.•Coronal hallux to forefoot range of motion varied by foot type during gait.•All variability measures were within the true sample variance.
Talonavicular (TN) fusion is a common treatment for TN arthritis or deformity correction. There is incongruous evidence regarding remaining motion at the talocalcaneal and calcaneocuboid joints after ...TN fusion. Additionally, the effects of a malaligned TN fusion are not well understood and alignment of the fusion may be important for overall foot integrity. This project assessed the kinematic and kinetic effects of neutral and malaligned TN fusions. Ten cadaveric feet were tested on a gait simulator in four conditions: unfused, fused in neutral, fused in varus, and fused in valgus. The fusions were simulated with external fixation hardware. An eight‐camera motion analysis system and a 10‐segment foot model generated kinematic data, and a pressure mat captured pressure data. Simulated TN fusion was achieved in eight feet. From unfused to fused‐neutral, range of motion (ROM) was not eliminated in the adjacent joints, but the positions of the joints changed significantly throughout stance phase. Furthermore, the ROM increased at the tibiotalar joint. Plantar pressure and center of pressure shifted laterally with neutral fusion. The malalignments marginally affected the ROM but changed joint positions throughout stance phase. Pressure patterns were shifted laterally in varus malalignment and medially in valgus malalignment. The residual motion and the altered kinematics at the joints in the triple joint complex after TN fusion may subsequently increase the incidence of arthritis. Clinical significance: This study quantifies the effects of talonavicular fusion and malalignment on the other joints of the triple joint complex.