Prevalence and pattern of lateral impingements in the progressive collapsing foot deformity.

INTRODUCTION: The prevalence of lateral bony impingements [i.e., Sinus Tarsi (STI), Talo-Fibular (TFI) and Calcaneo-Fibular (CFI)] and their association with Peritalar Subluxation (PTS) have not been clearly established for progressive collapsing foot deformity (PCFD).This study aims to assess the prevalence of STI, TFI and CFI in PCFD, in addition to their association with PTS. We hypothesized that STI and TFI would be more prevalent than CFI. MATERIALS AND METHODS: Seventy-two continuous symptomatic PCFD cases were retrospectively reviewed. Weightbearing computed tomography (WBCT) was used to assess lateral impingements and classified as STI, TFI and CFI. PTS was assessed by the percent of uncovered and the incongruence angle of the middle facet, and the overall foot deformity was determined by the foot and ankle offset (FAO). Data were collected by two fellowship-trained independent observers. RESULTS: Intra-observer and inter-observer reliabilities for impingement assessment ranged from substantial to almost perfect. STI was present in 84.7%, TFI in 65.2% and CFI in 19.4%. PCFD with STI showed increased middle facet uncoverage (p = 0.0001) and FAO (p = 0.0008) compared to PCFD without STI. There were no differences in FAO and middle facet uncoverage in PCFD with TFI and without TFI. PCFD with CFI was associated with STI in 100% of cases. PCFD with CFI showed decreased middle facet incongruence (p = 0.04) and higher FAO (p = 0.006) compared to PCFD without CFI. CONCLUSIONS: STI and TFI were more prevalent than CFI in PCFD. However, only STI was associated with PTS. Conversely, CFI was associated with less PTS, suggesting a different pathological mechanism which could be a compensatory subtalar behavior caused by deep layer failure of the deltoid ligament and talar tilt.

A comparison between the Bluman et al. and the progressive collapsing foot deformity classifications for flatfeet assessment.

INTRODUCTION: Bluman et al., flatfoot classification is based on posterior tibial tendon (PTT) dysfunction leading to a chronological appearance of several foot deformities. An expert consensus recently proposed a new classification named Progressive Collapsing Foot Deformity (PCFD) in which the focus was shifted to five different independent foot and ankle deformities and their flexibility or rigidity. The aim of this study was to compare Bluman and PCFD classifications. We hypothesize that both classifications will be reliable and that the PCFD classification will allow a larger distribution of the different types of foot deformity. MATERIALS AND METHODS: We performed a retrospective IRB-approved study including 92 flatfeet. Three foot and ankle surgeons reviewed patient files and radiographs to classify each foot using both classifications. Bluman classification was performed one time as initially described and a second time after removing the Angle of Gissane sclerosis sign. Interobserver reliabilities were determined with Fleiss' kappa values. RESULTS: Interobserver reliabilities of Bluman and PCFD classifications were, respectively, substantial 0.67 and moderate 0.55. PCFD Class C and D reliabilities were, respectively, slight 0.07 and fair 0.28. The 276 readings were spread into 10 substages in Bluman and 65 subclasses in PCFD. The progressivity of the Bluman classification prevented the combination of flexible hindfoot valgus (II Bluman, 1A PCFD), midfoot abduction (IIB, 1B) and medial column instability (IIC, 1C) which was frequent in our study (112/276 readings, 40.6%). By removing the Angle of Gissane sclerosis sign from the Bluman classification, the prevalence of stage III decreased from 44.2 to 10.1%. CONCLUSIONS: Bluman and PCFD classifications were reliable. The PCFD classification showed a larger distribution of different types of flatfeet but Classes C and D need better definition. The progressivity of Bluman classification causes inconsistencies and Gissane angle sclerosis sign is inappropriately used and might lead to incorrect surgical indications.

Distribution, prevalence, and impact on the metatarsosesamoid complex of first metatarsal pronation in hallux valgus.

BACKGROUND: Previous simulated weight-bearing CT (WBCT) studies classifying first metatarsal (M1) pronation suggested a high prevalence of M1 hyper-pronation in hallux valgus (HV). These findings have prompted a marked increase in M1 supination in HV surgical correction. No subsequent study confirms these M1 pronation values, and two recent WBCT investigations suggest lower normative M1 pronation values. The objectives of our WBCT study were to (1) determine M1 pronation distribution in HV, (2) define the hyperpronation prevalence compared to preexisting normative values, and (3) assess the relationship of M1 pronation to the metatarso-sesamoid complex. We hypothesized that the M1 head pronation distribution would be high in HV. METHODS: We retrospectively identified 88 consecutive feet with HV in our WBCT dataset and measured M1 pronation with the Metatarsal Pronation (MPA) and α angles. Similarly, using two previously published methods defining the pathologic pronation threshold, we assessed our cohort's M1 hyper-pronation prevalence, specifically (1) the upper value of the 95% confidence interval (CI95) and (2) adding two standard deviations at the mean normative value (2 SD). Sesamoid station (grading) was assessed on the coronal plane. RESULTS: The mean MPA was 11.4+/-7.4 degrees and the α angle was 16.2+/-7.4 degrees. According to the CI95 method, 69/88 HV (78.4%) were hyperpronated using the MPA, and 81/88 HV (92%) using the α angle. According to the 2 SD method, 17/88 HV (19.3%) were hyperpronated using the MPA, and 20/88 HV (22.7%) using the α angle. There was a significant difference in MPA among sesamoid gradings (p = 0.025), with a paradoxical decrease in MPA when metatarsosesamoid subluxation was increased. CONCLUSION: M1 head pronation distribution in HV was higher than in normative values, but threshold change demonstrated contradictory hyper-pronation prevalences (85% to 20%), calling into question the previously reported high prevalence of M1 hyper-pronation in HV. An increase in sesamoid subluxation was associated with a paradoxical decrease in M1 head pronation in our study. We suggest that a greater understanding of the impact of HV M1 pronation is warranted before routine M1 surgical supination is recommended for patients with HV. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Impact of First Metatarsal Hyperpronation on First Ray Alignment: A Study in Cadavers.

BACKGROUND: There is increased evidence of first metatarsal hyperpronation in patients with hallux valgus, but its impact on the stability of the first metatarsophalangeal and metatarsosesamoid joints is unknown. A previous biomechanical study showed that an increase in hallucal pronation might lead to medial soft tissue failure of the first metatarsophalangeal joint. Conversely, dynamic studies on hallux valgus have shown that the first tarsometatarsal joint moves in supination during weightbearing, and supination was associated with an increase in the intermetatarsal angle (IMA) and hallux valgus angle (HVA). QUESTIONS/PURPOSES: (1) Does an increase in first metatarsal pronation cause an increase in hallucal pronation? (2) Can an intrinsic increase in first metatarsal pronation lead to first ray supination during weightbearing? (3) Can a combination of intrinsic first metatarsal hyperpronation and first metatarsophalangeal medial soft tissue failure increase supination of the first ray during weightbearing? (4) Is first ray supination during weightbearing associated with an increase in the IMA and HVA? METHODS: Twelve transtibial, nonpaired cadaver specimens without deformities were used. Each specimen underwent six weightbearing CT scans under different conditions. The first three CT examinations were performed without any osteotomy of the first metatarsal. The first was a simulated nonweightbearing condition. The second was a simulated weightbearing condition. The third was a simulated weightbearing condition with medial soft tissue release. Subsequentially, a 30° pronation osteotomy of the first metatarsal was performed, and the same sequence of weightbearing CT images was obtained. On each weightbearing CT image, the HVA, IMA, sesamoid rotation angle, metatarsal pronation angle (MPA), metatarsosesamoid rotation angle, and hallucal pronation (HP) were measured. Motions were calculated based on the differential values of these angular measurements produced by the six different conditions (weightbearing, medial soft tissue release, 30° pronation osteotomy, and combinations of these conditions). We compared means using a t-test for normally distributed variables and the Mann-Whitney U test for nonnormally distributed variables. Correlations were assessed with Pearson product-moment correlation coefficients. RESULTS: We found that 30° pronation osteotomy of the first metatarsal increased the MPA and HP by 28° ± 4° and 26° ± 6°, respectively, in the nonweightbearing condition. No differences between the increase in MPA and the increase in HP were noted (mean difference 2° [95% CI -1° to 5°]; p = 0.20). Therefore, an increase in first metatarsal pronation caused an increase in hallucal pronation. When a 30° pronation osteotomy of the first metatarsal was performed, the first ray motion during weightbearing went from pronation to supination (4° ± 2° in pronation without osteotomy versus 4° ± 2° in supination after the osteotomy, mean difference 8° [95% CI 6° to 9°]; p < 0.001). Therefore, an intrinsic increase in pronation of the first metatarsal led to a first ray supination motion during weightbearing. When a first metatarsophalangeal medial soft tissue release was performed in addition to the 30° osteotomy of the first metatarsal, the supination motion of the first ray increased (4° ± 2° without medial soft tissue release versus 11° ± 7° after the release, mean difference 8° [95% CI 3° to 12°]; p = 0.003). Therefore, a combination of intrinsic first metatarsal hyperpronation and first metatarsophalangeal medial soft tissue failure increased supination of the first ray during weightbearing. Regarding static angular measurements, the HVA and IMA were not correlated with the MPA (ρ = 0.20; p = 0.09 and ρ = 0.22; p = 0.07, respectively). Regarding motions, as the HVA and IMA increased from nonweightbearing to weightbearing the pronation decreased, with strong correlations (ρ = -0.82; p < 0.001 and ρ = -0.77; p < 0.001, respectively). Therefore, a first ray supination during weightbearing was associated with an increase in the HVA and IMA. CONCLUSION: The combination of first metatarsal intrinsic hyperpronation and first metatarsophalangeal medial soft tissue failure led to a hallux valgus deformity in this cadaveric study. The static measurement of first metatarsal head pronation relative to the ground (MPA) did not reflect the real intrinsic pronation of the first ray, and foot and ankle specialists should be careful when interpreting these measurements. Hallux valgus is a dynamic condition, and the deformity could be more correlated with motions during weightbearing than with plain static measurements. CLINICAL RELEVANCE: First ray supination compensating for first metatarsal intrinsic hyperpronation might be an important factor in the hallux valgus pathogenesis. Further in vivo studies involving nonweightbearing and weightbearing comparative assessments of hallux valgus and controls should be performed to confirm this pathomechanism.

Does tibialis posterior dysfunction correlate with a worse radiographic overall alignment in progressive collapsing foot deformity? A retrospective study.

BACKGROUND: Posterior Tibial Tendon (PTT) dysfunction is considered to have an important role in Progressive Collapsing Foot Deformity (PCFD). The objective of our study was to assess the relationship between PTT status and three-dimensional foot deformity in PCFD. METHODS: Records from 25 patients with PCFD were included for analysis. The PTT was considered deficient in patients with a positive single heel rise test or a deficit in inversion strength. Three-dimensional foot deformity was assessed using the Foot and Ankle Offset (FAO) from Weight-Bearing-CT imaging. Hindfoot valgus, midfoot abduction and medial longitudinal arch collapse were assessed on X-Rays using hindfoot moment arm, talonavicular coverage angle and Meary's angle respectively. Deland and Rosenberg MRI classifications were used to classify PTT degeneration. RESULTS: PCFD with PTT deficit (13/25) had a mean FAO of 7.75 + /- 3.8% whereas PCFD without PTT deficit had a mean FAO of 6.68 + /- 3.9% (p = 0.49). No significant difference was found between these groups on the hindfoot moment arm and the talonavicular coverage angle (respectively p = 0.54 and 0.32), whereas the Meary's angle was significantly higher in case of PCFD with PTT deficit (p = 0.037). No significant association was found between PTT degeneration on MRI and FAO. CONCLUSION: PCFD associated three-dimensional deformity, hindfoot valgus and midfoot abduction were not associated with PTT dysfunction. PTT dysfunction was only associated with a worse medial longitudinal arch collapse in our study. Considering our results, it does not appear that PTT is the main contributor to PCFD. LEVEL OF EVIDENCE: Level III, Retrospective Comparative Study.

Risks of injury in distal metatarsal minimally invasive osteotomy when comparing standard and modified techniques: A cadaveric study.

BACKGROUND: The objectives of the study were to evaluate the structures at risk in distal metatarsal mini-invasive osteotomy (DMMO) and to compare standard and intraosseous approaches. METHODS: DMMO was performed on the second and fourth metatarsals of 11 fresh-frozen cadaveric specimens. The standard technique was performed in 11 metatarsals. It was then compared to a modified intraosseous technique that entails starting inside the bone in 11 other metatarsals. The cadavers were dissected to identify unintentional injury to soft tissue structures. RESULTS: In the standard group the most injured structures were the metatarsal joint capsules (MJC) (27%), extensor digitorum longus (EDL) (18%), and extensor digitorum brevis (EDB) (9%). The modified intraosseous group injured the EDL (27%), not the MJC (0%) and the EDB (0%). Distances between osteotomies and the dorsal metatarsal head articular surface (DMHAS) were 6.08 ± 3.99 mm in the standard and 9.92 ± 3.42 mm in the modified (p = 0.02). CONCLUSION: The DMMO techniques most frequently injured the EDL. Intra-articular positioning of the osteotomy was more observed in the standard. Overall, it appears the modified method could be an alternative to the standard DMMO. CLINICAL RELEVANCE: The modified minimally invasive DMMO has a comparable rate of potential iatrogenic injuries. This intraosseous procedure may present as an option when planning surgery to the lesser metatarsals. LEVEL OF EVIDENCE: Level III. Comparative Cadaveric Study.

Diagnosis of Achilles Insertional Tendinopathies by Algometry.

INTRODUCTION: Diagnosis of Achilles insertional tendinopathies (AIT) is based on pain by tendon palpation. However, there is no consensus or standard with regard to the amount of force to be used during the evaluation. Algometry is a method of measuring the pressure applied in a specific region and can be a method for determining diagnosis values. GOAL: To determine a cutoff value for pain threshold (PT) in the assessment of AIT. DESIGN: This is a prospective case-control study of diagnostic accuracy, to develop a diagnostic criterion. METHODS: Forty asymptomatic individuals and forty patients with AIT, matched by age and sex, were evaluated and submitted to algometry for PT and for visual analog scale (VAS) levels with 3 kgf at the insertion of the calcaneal tendon by two different evaluators. Inter-observer reproducibility was assessed through the interclass correlation coefficient (ICC). Sensitivity and specificity calculations of PT and of VAS were calculated and plotted on a receiver operating characteristic curve. RESULTS: The lowest ICC found was 0.788. With regard to the diagnosis through PT , the 4.08-kgf value showed the best relation between sensitivity and specificity (92.5% and 92.5%, respectively). Algometry values lower than 4.08 were considered positive for disease. For the diagnosis of AIT through VAS with 3 kgf, the value of 2.98 was estabilished (sensitivity of 92.5% and specificity of 97.5%). CONCLUSION: Algometry was shown to be a simple and reliable method for diagnosing AIT. Values of PT less than 4.08 kgf were found to be predictors of the disease.

Crossed versus lateral K-wire fixation of supracondylar fractures of the humerus in children: a meta-analysis of randomized controlled trials.

BACKGROUND: Supracondylar fractures of the humerus are common in children. Whether fixation should be performed with crossed or lateral wires remains controversial. We performed a meta-analysis of randomized controlled trials to evaluate both techniques in terms of the function of the elbow and the risk of neurologic injury and loss of reduction. We also assessed the quality of the evidence currently available. METHODS: The MEDLINE, Embase, Cochrane Library, and LILACS (Latin American and Caribbean Health Sciences Literature) databases, as well as ongoing clinical trial databases, were searched until March 2020. The main outcomes were function, measured by the Flynn criteria, and complications (neurologic lesions and loss of reduction). A meta-analysis was conducted using relative risk (RR) analysis for dichotomous variables and difference in means for continuous variables. Heterogeneity was tested using the I2 statistic. RESULTS: Twelve trials, with a total of 930 patients, met the inclusion criteria. Both groups (crossed-wire and lateral-wire fixation) presented satisfactory functional results, with no difference between them (RR, 0.99; 95% confidence interval [CI], 0.96-1.02; P = .44). Patients undergoing crossed-wire fixation had a higher risk of iatrogenic neurologic injury (RR, 0.45; 95% CI, 0.21-0.99; P = .05). The crossed group showed greater fixation stability, with a lower incidence of loss of fracture reduction (RR, 1.39; 95% CI, 1.04-1.85; P = .03). The GRADEpro GDT (Guideline Development Tool) showed that the quality of evidence of the evaluated outcomes was low or very low. CONCLUSION: There is evidence of very low quality that fixation with lateral wires is safer regarding iatrogenic nerve lesions whereas fixation with crossed wires is more effective at maintaining fracture reduction.

The Role of the Transverse Arch in Progressive Collapsing Foot Deformity.

BACKGROUND: The transverse arch (TA) has recently been shown to significantly increase the intrinsic stiffness of the midfoot when coupled with the medial longitudinal arch (MLA). Progressive collapsing foot deformity (PCFD) is a complex deformity that ultimately results in a loss of stiffness and collapse of the MLA. The role of the TA has not been investigated in patients diagnosed with this disorder using weightbearing CT (WBCT). Therefore, this study aims to answer the following questions: (1) Is the curvature of the TA decreased in PCFD? (2) Where within the midfoot does TA curvature flattening happen in PCFD? METHODS: A retrospective review of weightbearing CT images was conducted for 32 PCFD and 32 control feet. The TA curvature was assessed both indirectly using previously described methods and directly using a novel measurement termed the transverse arch plantar (TAP) angle that assesses the angle formed between the first, second, and fifth metatarsals in the coronal plane. Location of TA collapse was also assessed in the coronal plane. RESULTS: The TAP angle was significantly higher in PCFD (mean 115.2 degrees, SD 10.7) than in the control group (mean 100.8 degrees, SD 7.9) (P < .001). No difference was found using the calculated normalized TA curvature between PCFD (mean 17.1, SD 4.8) and controls (mean 18.3, SD 4.0) (P = .266). Location of collapse along the TA in PCFD was most significant at the second metatarsal and medial cuneiform. CONCLUSION: The TA is more collapsed in PCFD compared to controls. This collapse was most substantial between the plantar medial cuneiform and the plantar second metatarsal. This may represent a location of uncoupling of the TA and MLA. LEVEL OF EVIDENCE: Level III, retrospective case control.

Cone-Beam Weight-Bearing Computed Tomography of Ankle Arthritis and Total Ankle Arthroplasty.

Weight-bearing computed tomography has multiple advantages in evaluating the hindfoot and ankle. It can assess hindfoot and ankle alignment, pathology in ankle arthritis, and complications related to total ankle replacements. It is an essential tool in ankle osteoarthritis diagnostic, preoperative planning, and total ankle replacement outcomes. It allows for better accuracy and reproducibility of alignment and implant size. In addition, it has the potential to more assertively detect complications related to weight bearing.

Normal Values for Distal Tibiofibular Syndesmotic Space With and Without Subject-Driven External Rotation Stress.

BACKGROUND: The diagnosis and treatment of distal tibiofibular syndesmosis (DTFS) injury can be challenging, especially in cases of subtle instability that may be masked on 2-dimensional conventional radiographs. Weightbearing computed tomography (WBCT) has recently emerged as a useful diagnostic tool allowing direct assessment of distal tibiofibular area widening. The purpose of the current study was to examine and report normal threshold values for DTFS area measurements in a cohort of healthy volunteers, assessing the ankles in natural weightbearing position and under subject-driven external rotation stress. METHODS: In this prospective study, we enrolled 25 healthy volunteers without a history of DTFS injury or high ankle sprain, previous foot and ankle surgery, or current ankle pain. Subjects with any prior ankle injuries were excluded. Study participants underwent bilateral standing nonstress and external rotation stress WBCT scans. The DTFS area (mm2) was semiautomatically quantified on axial-plane WBCT images 1 cm proximal to the apex of the talar dome using validated software. Syndesmosis area values were compared between "unstressed" and "stressed" ankles, as well as left and right ankles. Statistical analysis was performed using independent t tests/Wilcoxon analysis with statistical significance defined as P <.05. RESULTS: The study cohort consisted of 50 ankles in 25 patients (12 males, 48%) with a mean age of 28.7 ± 9.3 years. In the unstressed ankle, the mean pooled DTFS area was determined to be 103.8 + 20.8 mm2. The mean syndesmosis area of unstressed left ankles (104.2 + 19.5 mm2) was similar to unstressed right ankles (109.2 + 17.2 mm2) in the cohort (P = .117). With external rotation stress, the DTFS area of left ankles (mean difference -0.304 mm2, CI -12.1 to 11.5; P = .082), right ankles (mean difference -5.5 mm2, CI 16.7-5.7; P = .132), and all ankles (mean difference -2.9 mm2, CI -10.8 to 5.1; P = .324) remained similar. CONCLUSION: This study presents normal values and range for DTFS area calculation. In uninjured ankles with expected intact ligaments, subject-driven external rotation stress did not result in significant widening of the DTFS space as imaged on with WBCT. LEVEL OF EVIDENCE: Level II, cross-sectional study.

Hindfoot Alignment in Flexible Cavovarus Deformity Under Orthostatic and Coleman Block Test Positions: A Weightbearing Computed Tomography Study.

BACKGROUND: Flexible cavovarus deformity is prevalent and the Coleman block test is frequently used to assess the first ray plantarflexion malpositioning in the overall deformity as well as the flexibility of the hindfoot. The objective was to assess and compare the weightbearing computed tomography (WBCT) 3-dimensional (3D) changes in clinical and bone alignment in flexible cavovarus deformity patients when performing the Coleman block test when compared to normal standing position and to controls. METHODS: Twenty patients (40 feet) with flexible cavovarus deformity and 20 volunteer controls (40 feet) with normal foot alignment underwent WBCT imaging of the foot and ankle. Cavovarus patients were assessed in normal orthostatic and Coleman block test positions. Foot and ankle offset (FAO), hindfoot alignment angle (HAA), talocalcaneal angle (TCA), subtalar vertical angle (SVA) and talonavicular coverage angle (TNCA) and a CT-simulated soft tissue envelope image, WBCT clinical hindfoot alignment angle (WBCT-CHAA), were evaluated by 2 readers. Measurements were compared between cavovarus nonstressed and stressed positions and to controls. P values of .05 or less were considered significant. RESULTS: The intra- and interobserver intraclass correlation coefficient were good or excellent for all WBCT measurements. Cavovarus patients demonstrated significant correction of WBCT-CHAA (9.7 ± 0.4 degrees), FAO (2.6 ± 0.4%), and TNCA (8.8 ± 1.8 degrees) when performing the Coleman block test (all P values <.0001). However, WBCT-CHAA and FAO measurements were still residually deformed and significantly different from controls (P values of .001 and <.0001, respectively). TNCA values corrected to values similar to healthy controls (P = .29). No differences were observed in cavovarus patients during Coleman block test for the coronal measures: HAA, TCA, and SVA measurements. CONCLUSION: In this study, we observed improvement in the overall 3D WBCT alignment (FAO), axial plane adduction deformity (TNCA), as well as CT simulated clinical hindfoot alignment (WBCT-CHAA) in flexible cavovarus deformity patients when performing a Coleman block test. However, we did not find improvement in measures of coronal alignment of the hindfoot, indicating continued varus positioning of the hindfoot in these patients.

Quantification of First Metatarsal Joint Surface Interactions in Hallux Rigidus Using Distance and Coverage Mapping: A Case-Control Study.

BACKGROUND: Weightbearing cone-beam computed tomography (WBCT) has proven useful for analysis of structural changes of the foot and ankle when compared to conventional radiographs. WBCT allows for extraction of distance and coverage mapping metrics, which may provide novel insight into hallux rigidus (HR). This study retrospectively assessed HR joint space using distance and coverage mapping in a case-control study. METHODS: WBCT images of the foot and ankle for 20 symptomatic HR and 20 control patients were obtained. Three-dimensional models were created and analyzed using a custom semiautomatic measurement algorithm. Distance and coverage mapping metrics for the first metatarsophalangeal and metatarsosesamoid joints were extracted from the models and compared between cohorts. Relationships between these metrics and visual analog scale (VAS) scores, a patient-reported outcome of pain, were assessed in HR patients. RESULTS: Overall first metatarsophalangeal joint space narrowing was noted in HR patients when compared to controls by an average of 11.8% (P = .02). However, no significant changes in the overall coverage of the joint were noted. Decreased joint space width and increased surface-to-surface coverage were only and particularly observed at the plantar medial quadrant of the first metatarsal head in HR patients relative to controls. VAS score was significantly but weakly correlated with dorsolateral quadrant coverage (R2 = 0.26, P = .03). CONCLUSION: Distance and coverage mapping serve as a complementary option to current techniques of quantifying HR changes. These metrics can expand the scope of future work investigating joint articulation changes in HR.

High-Ankle Sprain and Syndesmotic Instability: How Far Have We Come with Diagnosis and Treatment?

Probably one of the most controversial subjects in the orthopedic field is the distal tibiofibular articulation. Even though its most primary knowledge can be a matter of enormous debate, it is in the diagnosis and treatment most of the disagreements reign. Distinguishing between injury and instability remains challenging as well as an optimal clinical decision regarding surgical intervention. The last years presented technology and that was able to bring body to an already well-developed scientifical rationale. In this review article, we aim to demonstrate the current data behind syndesmotic instability in the ligament scenario, whereas using few fracture concepts.

Cone-Beam Weight-Bearing Computed Tomography of Ankle Arthritis and Total Ankle Arthroplasty.

Weight-bearing computed tomography has multiple advantages in evaluating the hindfoot and ankle. It can assess hindfoot and ankle alignment, pathology in ankle arthritis, and complications related to total ankle replacements. It is an essential tool in ankle osteoarthritis diagnostic, preoperative planning, and total ankle replacement outcomes. It allows for better accuracy and reproducibility of alignment and implant size. In addition, it has the potential to more assertively detect complications related to weight bearing.

Risks Associated With Posterior Ankle Hindfoot Arthroscopy Complications.

BACKGROUND: The use of posterior ankle and hindfoot arthroscopy (PAHA) has been expanding over time. Many new indications have been reported in the literature. The primary objective of this study was to report the rate of PAHA complication in a large cohort of patients and describe their potential associations with demographical and surgical variables. METHODS: In this IRB-approved retrospective comparative study, patients who underwent posterior ankle and/or hindfoot arthroscopy in a single institution from December 2009 to July 2016 were studied. Three fellowship-trained orthopaedic foot and ankle surgeon performed all surgeries. Demographic data, diagnosis, tourniquet use, associated procedures, and complications were recorded. To investigate a priori factors predictive of neurologic complication after PAHA, univariate and multivariable logistic regression was utilized. Where appropriate, sparse events sensitivity analysis was tested by fitting models with Firth log-likelihood approach. RESULTS: A total of 232 subjects with 251 surgeries were selected. Indications were posterior ankle impingement (37%), flexor hallux longus disorders (14%), subtalar arthritis (8%), and osteochondral lesions (6%). Complications were observed in 6.8% (17/251) of procedures. Neural sensory lesions were noted in 10 patients (3.98%), and wound complications in 4 ankles (1.59%). Seven neurologic lesions resolved spontaneously and 3 required further intervention. In a multivariable regression model controlled for confounders, the use of accessory posterolateral portal was the significant driver for neurologic complications (odds ratio [OR] 32.19, 95% CI 3.53-293.50). CONCLUSION: The complication rate in this cohort that was treated with posterior ankle and/or hindfoot arthroscopy was 6.8%. Most complications were due to neural sensorial injuries (sural 5, medial plantar nerve 4, medial calcaneal nerve 1 ) and 3 required additional operative treatment. The use of an accessory posterolateral portal was significantly associated with neurologic complications. The provided information may assist surgeons in establishing diagnoses, making therapeutic decisions, and instituting surgical strategies for patients that might benefit from a posterior arthroscopic approach. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Effect of Peritalar Subluxation Correction for Progressive Collapsing Foot Deformity on Patient-Reported Outcomes.

BACKGROUND: Peritalar subluxation (PTS) is part of progressive collapsing foot deformity (PCFD). This study aimed to evaluate initial deformity correction and PTS optimization in PCFD patients with flexible hindfoot deformity undergoing hindfoot joint-sparing surgical procedures and its relationship with improvements in patient-reported outcome measures (PROMs) at latest follow-up. We hypothesized that significant deformity/PTS correction would be observed postoperatively, positively correlating with improved PROMs. METHODS: A prospective comparative study was performed with 26 flexible PCFD patients undergoing hindfoot joint-sparing reconstructive procedures, mean age 47.1 years (range, 18-77). We assessed weightbearing computed tomography (WBCT) overall deformity (foot and ankle offset [FAO]) and PTS markers (distance and coverage maps) at 3 months, as well as PROMs at final follow-up. A multivariate regression model assessed the influence of initial deformity correction and PTS optimization in patient-reported outcomes. RESULTS: Mean follow-up was 19.9 months (6-39), and the average number of procedures performed was 4.8 (2-8). FAO improved from 9.4% (8.4-10.9) to 1.9% (1.1-3.6) postoperatively (P < .0001). Mean coverage improved by 69.6% (P = .012), 12.1% (P = .0343) and 5.2% (P = .0074) in, respectively, the anterior, middle, and posterior facets, whereas the sinus tarsi coverage decreased by an average 57.1% (P < .0001) postoperatively. Improvements in patient-reported outcomes were noted for all scores assessed (P < .03). The multivariate regression analysis demonstrated that improvement in both FAO and PTS measurements significantly influenced the assessed PROMs. CONCLUSION: This study demonstrated significant improvements in the overall 3D deformity, PTS markers, and PROMs following hindfoot joint-sparing surgical treatment in patients with flexible PCFD. More importantly, initial 3D deformity correction and improvement in subtalar joint coverage and extraarticular impingement have been shown to influence PROMs significantly and positively. Addressing these variables should be considered as goals when treating PCFD. LEVEL OF EVIDENCE: Level II, prospective cohort study.

Influence of Weightbearing Computed Tomography in the Progressive Collapsing Foot Deformity Classification System.

BACKGROUND: The objective of this study was to compare progressive collapsing foot deformity (PCFD) classifications performed using clinical and conventional radiographs (CR) with classifications established using clinical and weightbearing computed tomography (WBCT). METHODS: This retrospective comparative study evaluated 89 consecutive PCFD feet (84 patients). Three readers performed chart reviews and CR evaluations, determining PCFD classifications that were previously published. After a washout period, the sequence was randomized, and a new classification was executed using clinical and WBCT assessment. One of the readers repeated the WBCT evaluation for intrarater reliability. RESULTS: Interrater reliability for the WBCT was found moderate (0.55) and intrarater excellent (0.98). Evaluation using WBCT produced 29.6% of 1ABC (CR: 25.4%, P = .270), 11.6% of 1ABCD (CR: 6.9%, P = .081), and 6.4% of BC (CR: 3.3%, P = .090) as most prevalent. Class A was presented in 83.9% (CR: 89.5%, P = .55), class B in 89.9% (CR: 76.4%, P < .001), class C in 93.6% (CR: 86.2%, P = .004), class D in 46.4% (CR: 34.8%, P = .006), and class E in 27.7% (CR: 22.5%, P = .158) of the classifications performed by WBCT. CONCLUSION: WBCT showed a different rate of deformity recognition, which increased the incidence of all classes, especially B, C, and D. An excellent intrarater agreement was found, which infers assessment reliability combining clinical and WBCT evaluation. The obtained information could enhance disease understanding and supply patients with more precise care. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Association Between Middle Facet Subluxation and Foot and Ankle Offset in Progressive Collapsing Foot Deformity.

BACKGROUND: Subtalar middle facet (MF) subluxation was recognized as a reliable marker for progressive collapsing foot deformity (PCFD) diagnosis. Foot and Ankle Offset (FAO) is an established measurement, predictive of malalignment severity. The objective of this study was to assess the potential association between MF subluxation and FAO in PCFD patients. METHODS: 56 individuals with flexible PCFD (74 feet) were assessed. Two blinded foot and ankle surgeons calculated MF uncoverage, MF incongruence, and FAO. Agreement was quantified using intraclass correlation coefficient (ICC). A multivariate regression analysis and partition prediction models were applied to assess relationship between values. RESULTS: All ICCs were >0.80. MF subluxation and FAO were found to be correlated (rs = 0.56; P < .0001). Changes in the MF subluxation were noticeably explained by FAO and BMI (R2 = 0.33). MF incongruence was not correlated with the assessed variables (P = .10). In this cohort, an MF subluxation of 27.5% was a threshold for increased FAO (FAO of 3.4%±2.4% when below; FAO of 8.0% ±3.5% when above). CONCLUSION: We found a correlation between MF subluxation and FAO. An MF subluxation of 27.5% was found to be a threshold for higher FAO, which corresponded to a greater malalignment. These data may help surgeons optimize treatment decisions in PCFD patients. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Deformity Correction in Ankle Osteoarthritis Using a Lateral Trans-Fibular Total Ankle Replacement: A Weight-Bearing CT Assessment.

Background: Ankle osteoarthritis (AO) is often secondary to prior trauma and frequently presents with joint deformity. Total ankle replacement (TAR) has been shown as a viable surgical option to reduce pain, improve function, and preserve ankle joint range of motion. The standard TAR uses an anterior approach, but recently a lateral trans-fibular approach has been developed. Our aim was to determine if the lateral TAR was able to correct alignment and improve patient reported outcomes (PROs) in patients with end-stage AO. Methods: This IRB-approved, retrospective comparative study included 14 consecutive patients that underwent lateral trans-fibular approach TAR for end-stage AO. All patients had received pre-and post-operative WBCT imaging on the affected foot and ankle. Using multiplanar reconstruction of WBCT images, measures of coronal and sagittal plane ankle alignment: Foot and Ankle Offset (FAO), Talar Tilt Angle (TTA), Hindfoot Moment Arm (HMA), and Lateral Talar Station (LTS) were performed. PROs were collected pre- and postoperatively at the latest clinical follow-up. Results: All patients demonstrated a significant deformity correction in all measurements performed: FAO (7.73%-3.63%, p=0.031), HMA (10.93mm - 5.10mm, p=0.037), TTA (7.9o-1.5o, p=0.003), and LTS (5.25mm-2.83mm, p=0.018). Four of the PROs measured exhibited significant improvement postoperatively, the Tampa Scale for Kinesiophobia (TSK) (42.7-34.5, p=0.012), PRO-MIS Global Physical Health (46.1-54.5, p=0.011), EFAS (5-10.3, p=0.004), and FAAM Daily Living (60.5-79.7, p=0.04). Multivariate analysis assessing the influence of deformity correction in the improvements of PROs found that PROMIS Global Physical Health was significantly associated with improvements in FAO and LTS, TSK associated with HMA, and FAAM Daily Living with FAO and TTA (p<0.05). Conclusion: The results of this retrospective comparative cohort study suggest that the lateral trans-fibular TAR can correct different aspects of AO deformity. The method also impacted PROs, particularly TSK, PROMIS Global Physical Health, EFAS, and FAAM Daily Living. Direct correlation between some of the deformity correction measurements and the significantly improved PROs was found. The obtained data could help surgeons when making treatment decisions and be the base for comparative prospective studies. Level of Evidence: III.