Combined vertical and external rotational force in plantarflexion position produces posterior pilon fracture: A preliminary cadaveric study.

BACKGROUND: Posterior pilon fracture is speculated to occur by a combination of rotation and axial load, which makes it different from rotational posterior malleolar fracture or pilon fracture, but is not validated in vitro. The aim of the current study is to investigate the injury mechanisms of posterior pilon fracture on cadaveric specimens. METHODS: Eighteen cadaveric specimens were mounted to a loading device to undergo solitary vertical loading, solitary external rotational loading, and combined vertical and external rotational loading until failure, in initial position of plantarflexion with or without varus. The fracture characteristics were documented for each specimen. RESULTS: Vertical loading force combined with external rotation force diversified the fracture types resulting in pilon fracture, tibial spiral fracture, rotational malleolar fracture, talar fracture or calcaneal fracture. Vertical violence combined with external rotational loading in position of 45° of plantarflexion and 0° of varus produced posterior pilon fracture in specimens No. 13 and 14. CONCLUSION: Combination of vertical and external rotational force in plantarflexion position on cadaveric specimens produce posterior pilon fracture.

Use of Ankle Dorsiflexion and the Dimeglio and Pirani Scores in Predicting Relapse of Clubfoot Treated With the Ponseti Method.

Although Dimeglio and Pirani scores are frequently employed to rate the severities of clubfoot and to evaluate treatment outcomes, it is unclear if these scores predict relapse after treatment. Ankle dorsiflexion has been suggested in recent years to be a promising predictor of relapse. The aim of this study was to investigate ankle dorsiflexion and Dimeglio and Pirani scores in predicting the relapse of clubfoot after treatment with the Ponseti method. We included patients with clubfoot previously treated by the Ponseti method, and retrospectively analyzed their initial ankle dorsiflexion, Pirani and Dimeglio scores, number of castings, and the occurrence of relapse. We analyzed 218 feet of 176 infants with clubfoot who showed an incidence of relapse of 17.0% (30/176). The mean initial Pirani and Dimeglio scores of the feet showing recurrence were significantly higher than individuals with non-recurrence (p < .001 each). We observed a robust association between Pirani and Dimeglio scores and the recurrence of clubfoot at the last follow-up (γ = 0.53, p = .001). In contrast, ankle dorsiflexion was negatively correlated with recurrence of clubfoot (γ = -0.21, p = .001). Dimeglio scores significantly predicted the recurrence of clubfoot (p = .014). Receiver operating characteristic curve analysis exhibited slightly better performance regarding the Dimeglio score relative to the Pirani score and ankle dorsiflexion in predicting recurrence. Ankle dorsiflexion and Pirani and Dimeglio scores were related to recurrence in patients with clubfoot. However, the Dimeglio score reflected superior accuracy in predicting the prognosis of clubfoot treated with the Ponseti method.

Functional effects of arthroscopic modified Broström procedure on lateral ankle instability: A pilot study.

BACKGROUND: This study aims to assess the mechanical and functional effects of the arthroscopic modified Broström procedure (AMBP) on patients with lateral ankle instability. METHODS: Eight patients with unilateral ankle instability treated with AMBP and eight healthy subjects were recruited. Healthy subjects, preoperative and one-year postoperative patients were assessed using outcome scales and the Star Excursion Balance Test (SEBT) for dynamic postural control. One-dimensional statistical parametric mapping was performed to compare ankle angle and muscle activation curve during stair descent. RESULTS: The patients with lateral ankle instability showed good clinical outcomes and increased posterior lateral reach during the SEBT after the AMBP (p = 0.046). The medial gastrocnemius activation after initial contact was reduced (p = 0.049), and the peroneal longus activation after initial contact was promoted (p = 0.014). CONCLUSION: The AMBP has functional effects of promoting dynamic postural control and peroneal longus activation within one year of follow-up, which can benefit patients with functional ankle instability. However, the medial gastrocnemius activation was unexpectedly reduced post operation.

The influence of local pain on balance control in patients with chronic ankle instability.

BACKGROUND: Local pain around the ankle joint is a common symptom in patients with chronic ankle instability (CAI). However, whether the local pain would impose any influence on the balance control performance of CAI patients is still unknown. METHODS: A total of twenty-six subjects were recruited and divided into the following two groups: pain-free CAI (group A) and pain-present CAI (group B). Subjects in both groups received two independent tests: the star excursion balance test and the single-leg stance test, in order to reflect their balance control ability more accurately. RESULTS: Compared with group A, the group B showed significantly more episodes of the history of sprains, decreased ankle maximum plantarflexion angle, and lower Cumberland scores (all p < 0.05). In the star excursion balance test, group B demonstrated a significantly reduced anterior reach distance than group A (p < 0.05). During the single leg stance test, group B showed a significant increase in the magnitude of electromyographic signals both in peroneus longus and soleus muscles than group A (each p < 0.05). Additionally, group B had a significantly more anterolaterally positioned plantar center of pressure than group A (p < 0.05). CONCLUSION: CAI patients with local pain around the ankle joint had more episodes of sprains and lower functional scores when compared to those without pain. The balance control performance was also worse in the pain-present CAI patients than those without pain.

Surgical management of concurrent lateral ankle instability and osteochondral lesions of the talus increases dynamic sagittal ankle range of motion.

PURPOSE: A biomechanical study, in which imaging modalities are used to strictly include patients with concurrent lateral ankle instability (LAI) and osteochondral lesions of the talus (OLT), is needed to demonstrate the static and dynamic ankle range of motion (ROM) restriction in these patients, and determine whether ankle ROM restriction can be corrected postoperatively. METHODS: Eight patients with concurrent LAI and OLT treated with the arthroscopic modified Broström procedure and microfracture were recruited from June 2019 to January 2020. Patients were assessed using outcome scales, static ankle ROM, and a stair descent gait analysis for dynamic ankle ROM, a day prior to surgery and one year postoperatively. Eight healthy subjects were assessed using the same modalities upon recruitment. Operative outcomes and variables during stair descent were documented and compared among the preoperative, postoperative, and healthy groups. A curve analysis, one-dimensional statistical parametric mapping, was performed to compare the dynamic ankle kinematics and muscle activation curves over the entire normalised time series. RESULTS: The functional outcomes of patients with concurrent LAI and OLT were significantly worse than those of healthy subjects preoperatively, but were partially improved postoperatively. Patients had decreased static and dynamic ROM preoperatively, and static ROM did not significantly increase postoperatively (preoperative, 39.6 ± 11.3; postoperative, 44.9 ± 7.1; healthy, 52.0 ± 4.6; p = 0.021). Patients showed increased dynamic ankle flexion ROM (preoperative, 41.2 ± 11.6; postoperative, 53.6 ± 9.0; healthy, 53.9 ± 3.4; p = 0.012) postoperatively, as well as increased peroneus longus activation (preoperative, 35.8 ± 12.0; postoperative, 55.4 ± 25.1; healthy, 71.9 ± 13.4; p = 0.002) and muscle co-contraction of the tibialis anterior and peroneus longus (preoperative, 69.4 ± 23.4; postoperative, 88.4 ± 9.3; healthy, 66.2 ± 18.1; p = 0.045). CONCLUSIONS: Patients with concurrent LAI and OLT had decreased static and dynamic sagittal ankle ROM and altered neuromuscular activation patterns. The arthroscopic modified Broström procedure and microfracture did not significantly increase the static sagittal ankle ROM. However, the dynamic sagittal ankle ROM, peroneus longus activation and muscle co-contraction of the tibialis anterior and peroneus longus increased postoperatively. LEVEL OF EVIDENCE: IV.

The effect of partial deltoid ligament injuries on the external rotation stability: A cadaveric study.

BACKGROUND: The anterior and posterior part of the deltoid ligament have different functions during ankle flexion motion. Partial ligament injuries have been demonstrated in previous clinical reports. However, the efficacy of external rotation stress test in partial injured cases is unavailable till now. METHODS: Thirty-two fresh cadaveric specimens were included and allocated into two destabilization groups. In the first group, the anterior portion of deltoid ligament (DL) and syndesmotic ligament were sequentially severed, while in the second group, the posterior portion of DL and syndesmotic ligament were sequentially severed. Mortise view radiographs were taken after each destabilization stage when the ankles were placed at plantarflexion and dorsiflexion positions and stressed in standard external rotation force. The medial clear space (MCS) and talar tilt (TT) angle were measured and compared among different destabilization stages. RESULTS: When the ankles were placed at neutral position, the TT significantly increased in all destabilization stages. The MCS significantly increased after the partial deltoid ligament ruptures only with presence of syndesmotic ligament injuries. There was no significant difference of MCS at plantarflexion for all stages of destabilization if the anterior portion of DL is preserved. Similarly, no significant increase of MCS was detected at dorsiflexion if the posterior portion of DL and posterior inferior tibiofibular ligament are intact. CONCLUSION: Partial DL rupture causes ankle rotational instability at different ankle joint positions, especially when combined with syndesmotic injuries. The neutral position is recommended for diagnosis of partial DL ruptures under external rotation stress.

Length change pattern of the ankle deltoid ligament during physiological ankle motion.

BACKGROUND: Length change pattern of the ankle deltoid ligament during physiological ankle motion is still confused currently and had not been studied in vivo. METHODS: The deltoid ligaments from 7 cadaveric specimens were dissected. Lengths of each band during 30° plantarflexion to 20° dorsiflexion were measured. A dual fluoroscopy imaging system was utilized to capture the images of hindfoot joint of 7 healthy subjects during the stance phase of walking. 3D bone models were reconstructed from CT images. Lengths of each band were calculated after model-image registration utilizing a solid modeling software. Percentage of length variation and poses when the bands were in maximum extension were documented among each band. RESULTS: The anterior border of tibiocalcaneal ligament (TCL) had only 1.7% length variation in vitro and 5.7% length variation in vivo. The tibionavicular ligament, tibiospring ligament, and deep anterior tibiotalar ligament were in maximum extension at 30° plantarflexion, however, superficial posterior tibiotalar ligament, deep posterior tibiotalar ligament, and the posterior border of TCL were in maximum extension at 20° dorsiflexion. The tibionavicular ligament, tibiospring ligament, and deep anterior tibiotalar ligament were in maximum extension during foot flat. The TCL was in maximum extension during midstance. The superficial posterior tibiotalar ligament and deep posterior tibiotalar ligament were in maximum extension during heel off and toe off. CONCLUSION: The length of TCL did not change during ankle dorsiflexion and plantarflexion. The bands anterior to and posterior to the TCL showed different length change pattern during physiological ankle dorsiflexion and plantarflexion.

Histone deacetylase inhibitor chidamide induces growth inhibition and apoptosis in NK/T lymphoma cells through ATM-Chk2-p53-p21 signalling pathway.

We investigated the anti-tumour effects and the underlying molecular mechanisms of a new oral histone deacetylase inhibitor (HDACi), chidamide, in NK/T cell lymphoma (NKTCL), a rare and highly aggressive non-Hodgkin lymphoma with poor outcomes. SNT-8 and SNK-10 NKTCL cell lines were exposed to different concentrations of chidamide for the indicated time. The treated cells were analysed for cell proliferation, cell cycle progression, and cell apoptosis. Proteins in the AKT/mTOR and MAPK signalling pathways and the DNA damage response (DDR) cell cycle checkpoint pathway were measured by Western blotting. Chidamide inhibited cell proliferation in a dose- and time-dependent manner, arrested cell cycle progression at the G0/G1 phase, and induced apoptosis in the NKTCL cell lines. In addition, we found that chidamide suppressed the phosphorylation levels of proteins in the AKT/mTOR and MAPK signalling pathways and activated the DDR cell cycle checkpoint pathway, that is, the ATM-Chk2-p53-p21 pathway. Expression of EBV genes was also assessed by Real-Time PCR. Chidamide induced EBV lytic-phase gene expression in EBV-positive NKTCL. Our results provide evidence that chidamide shows antitumour effects by inhibiting the AKT/mTOR and MAPK signalling pathways and activating the ATM-Chk2-p53-p21 signalling pathway in vitro.

Steroidogenic Acute Regulatory Protein (StAR) Overexpression Reduces Inflammation and Insulin Resistance in Obese Mice.

Steroidogenic acute regulatory protein (StAR), a mitochondrial cholesterol delivery protein, plays a beneficial role in hyperlipidemia, NAFLD, and endothelial inflammation. Elevated circulating fatty acids and low grade inflammation are known as key risk factors of insulin resistance and type 2 diabetes. In the present study, C57BL/6J mice were fed with HFD and infected with recombinant adenovirus expressing StAR by tail-vein injection. Intraperitoneal glucose/insulin tolerance test was performed to assess the insulin sensitivity. Morphological analysis and intramuscular lipid determination were used to illustrate the adipose hypertrophy and ectopic fat accumulation in skeletal muscle. The levels of inflammatory factor and nitric oxide were determined by ELISA and classic Griess reagent methods, respectively. The fatty acids composition was analysis using gas chromatography-mass spectrometry (GC-MS). The expression of genes associated with inflammation and insulin resistance were determined by Western blotting and qPCR to elucidate the underlying mechanism. We demonstrated that StAR overexpression ameliorated insulin resistance and systemic inflammatory response with the reduction of adipose hypertrophy and intramuscular lipid in HFD-fed mice. In addition, StAR overexpression increased serum unsaturated fatty acids (UFAs) and PPARγ expression in muscle and adipose tissue of obese mice. In conclusion, StAR may activate PPARγ by increasing UFAs, which leads to a protective role in systemic inflammation and insulin resistance in obese mice. J. Cell. Biochem. 118: 3932-3942, 2017. © 2017 Wiley Periodicals, Inc.

Effect of memory CD4+ T cells' signal transducer and activator of transcription (STATs) functional shift on cytokine-releasing properties in asthma.

BACKGROUND: Recent data have demonstrated that long-lived memory T cells are present in the human lung and can play significant roles in the pathogenesis of specific allergic and autoimmune diseases. However, most evidence has been obtained from mouse studies, and the potential roles of memory T cells in human allergic diseases, such as asthma, remain largely unknown. METHODS: Thirty-three asthmatics, 26 chronic obstructive pulmonary disease (COPD) patients, and 22 healthy volunteers were enrolled in this study. Peripheral blood mononuclear cells (PBMCs) were isolated from the peripheral blood, and cell surface staining (CD4, CD45RO, CRTH2, CD62L, and CCR7) was performed for the detection of memory CD4+ T cells in blood. After stimulation with interleukin-27 (IL-27) or IL-4 for 15 min, the STAT1/STAT6 phosphorylation of memory CD4+ T cells was measured separately by flow cytometric techniques. The cytokine-releasing profiles after 6 days of culture under neutralization, TH2, TH2 + lipopolysaccharide (LPS), and TH2 + house dust mite (HDM) conditions were detected by intracellular protein (IL-5, IL-17, and interferon (IFN)-γ) staining. Correlation analyses between the profile of memory CD4+ T cells and clinical characteristics of asthma were performed. RESULTS: The number of circulating memory CD4+ T (CD4+ Tm) cells in asthmatics was increased compared with that in the healthy subjects (48 ± 5.7 % vs. 32 ± 4.1 %, p < 0.05). Compared with COPD and healthy subjects, the phosphorylation of signal transducer and activator of transcription 1 (STAT1-py) was impaired in asthmatics, whereas the phosphorylation of signal transducer and activator of transcription 6 (STAT6-py) was slightly enhanced. This imbalance of STAT1-py/STAT6-py was attributed to TH2 memory cells but not non-TH2 memory cells in blood. The cytokine-releasing profiles of asthmatics was unique, specifically IL-5high, IL-17high, and IFN-rlow, compared with those of COPD patients and healthy subjects. The IL-17 production levels in CD4+ Tm cells are associated with disease severity and positively correlated with medication consumption in asthma. CONCLUSIONS: The long-lived, antigen-specific memory CD4+ T cells, rather than PBMCs or peripheral lymphocytes, might be the ideal T cell subset candidates for analyzing the endotype of asthma. Memory CD4+ T cells exhibiting a shift in STAT phosphorylation and specific cytokine-releasing profiles have the potential to facilitate the understanding of disease heterogeneity and severity, allowing the more personalized treatment of patients.

Pain alleviation improves balance control and muscular coordination of lower limbs in patients with chronic ankle instability during sinusoidal perturbations.

BACKGROUND: It is well established that individuals with chronic ankle instability manifest deficits in balance control and muscle activation. Given the prevalence of pain as a prominent symptom in this population, there is a need for in-depth investigation of its role in contributing to these impairments. METHODS: A Stewart platform was used to generate translational sinusoidal perturbations in the antero-posterior direction. Eighteen individuals with chronic ankle instability and concurrent ankle pain were recruited. They were instructed to assume a central stance on the support surface with open eyes both before and 30 min after local analgesia. Data of center of pressure and electromyography of the tibialis anterior and medial gastrocnemius were recorded. Statistical analysis was performed to make comparisons pre- and post-analgesia using two-tailed paired t-test for the continuous variables. FINDINGS: Pain intensity was significantly decreased after local anesthetic injections. Antero-posterior center of pressure parameters significantly decreased following the injection. Also, there was an increase in the regularity of the center of pressure pattern. The electromyographic pattern of the tibialis anterior and medial gastrocnemius exhibited various activation patterns. After pain alleviation, the characteristic electromyographic response of the tibialis anterior and medial gastrocnemius was reciprocal contraction and relaxation that corresponded with the sinusoidal pattern of the perturbations. INTERPRETATION: Individuals who had chronic ankle instability and ankle pain demonstrated impaired balance control during sinusoidal perturbations. Mitigating pain improved their balance performance, evident in the center of pressure pattern and the coordination of lower limb muscles.

Brain and serum metabolomic studies reveal therapeutic effects of san hua decoction in rats with ischemic stroke.

San Hua Decoction (SHD) is a traditional four-herbal formula that has long been used to treat stroke. Our study used a traditional pharmacodynamic approach combined with systematic and untargeted metabolomics analyses to further investigate the therapeutic effects and potential mechanisms of SHD on ischemic stroke (IS). Male Sprague-Dawley rats were randomly divided into control, sham-operated, middle cerebral artery occlusion reperfusion (MCAO/R) model and SHD groups. The SHD group was provided with SHD (7.2 g/kg, i.g.) and the other three groups were provided with equal amounts of purified water once a day in the morning for 10 consecutive days. Our results showed that cerebral infarct volumes were reduced in the SHD group compared with the model group. Besides, SHD enhanced the activity of SOD and decreased MDA level in MCAO/R rats. Meanwhile, SHD could ameliorate pathological abnormalities by reducing neuronal damage, improving the structure of damaged neurons and reducing inflammatory cell infiltration. Metabolomic analysis of brain and serum samples with GC-MS techniques revealed 55 differential metabolites between the sham and model groups. Among them, the levels of 12 metabolites were restored after treatment with SHD. Metabolic pathway analysis showed that SHD improved the levels of 12 metabolites related to amino acid metabolism and carbohydrate metabolism, 9 of which were significantly associated with disease. SHD attenuated brain inflammation after ischemia-reperfusion. The mechanisms underlying the therapeutic effects of SHD in MCAO/R rats are related to amino acid and carbohydrate metabolism.

Diagnostic Evaluation of Mechanical Ankle Instability by Comparing Injured and Uninjured Contralateral Ankles Using Arthrometry.

CONTEXT: Individuals with mechanical ankle instability (MAI) have obvious lateral ligament laxity and excessive ankle joint motion beyond the physiological range. Arthrometry has been introduced to quantitatively measure the laxity of the ankle joint. However, the diagnostic accuracy of arthrometry in MAI is still debatable. OBJECTIVES: To (1) evaluate the difference in laxity between bilateral ankles in patients with and those without MAI and (2) calculate the diagnostic accuracy of ankle arthrometry using bilateral comparisons. DESIGN: Cross-sectional study. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 38 individuals with unilateral MAI (age = 31.24 ± 7.90 years, height = 168.93 ± 7.69 cm, mass = 65.72 ± 10.47 kg) and 38 individuals without MAI (control group; age = 32.10 ± 7.10 years, height = 166.59 ± 7.89 cm, mass = 62.93 ± 10.72 kg). MAIN OUTCOME MEASURE(S): Bilateral ankle laxity in each participant was quantitatively measured by performing the arthrometric anterior drawer test. Continuous data of loading force and joint displacement were recorded. Data from both ankles were compared for the ankle joint displacement at a loading force of 75 N (D75) and load-displacement ratio from 10 to 40 N (LDR 10-40). RESULTS: The D75 between injured and uninjured ankles in patients with MAI was different (t37 = 9.78, P < .001). The mean LDR 10-40 in injured ankles was higher than that in uninjured ankles (t37 = 9.80, P < .001). In the control group, no differences were found between the left and right ankles. The MAI group had larger bilateral differences than the control group (t37 range = 7.33-8.18; P < .001). When LDR 10-40 was used to diagnose MAI, the arthrometer showed sensitivity and specificity of 0.900 and 0.933, respectively, with a cutoff value of 0.0351 mm/N. CONCLUSIONS: An ankle arthrometer can be used to quantitatively measure the difference in bilateral ankle laxity in patients with MAI. Arthrometer-measured LDR 10-40 can be used to diagnose MAI with high diagnostic accuracy.

Stress Tests for Deltoid Ligament and Syndesmosis Injury in Patients With Ankle Fracture: A Systemic Review With Meta-Analysis.

OBJECTIVES: To determine the diagnostic accuracy of various stress tests for deltoid ligament and syndesmosis injury in patients with ankle fracture. DATA SOURCES: A systemic literature search was conducted in the MEDLINE, Embase, and Cochrane Library databases to identify studies published from January 1990 to August 2022. STUDY SELECTION: Studies that evaluated external rotation or gravity stress tests or hook or tap tests for the diagnosis of deltoid ligament or syndesmosis injury were included. DATA EXTRACTION: Authors, publication years, study design, index tests, reference standards, demographic features of participants, reliability, and the numbers of true-positive, true-negative, false-positive, and false-negative subjects were extracted from 14 included studies. Article quality was assessed through the revised Quality Assessment of Diagnostic Accuracy Studies tool. DATA SYNTHESIS: The pooled sensitivity and specificity of each index test for each structure were calculated with a random-effects model using the extracted data of true-positive, true-negative, false-positive, and false-negative outcomes in all relevant studies. The overall diagnostic performance of the different index tests for different structures was determined with the estimation of the area under the curve using the summary receiver operating characteristics curve. CONCLUSIONS: The gravity stress test and the tap test exhibited high sensitivity and specificity in diagnosing deltoid ligament injury. The hook test has relatively high accuracy in diagnosing syndesmosis injury. Further studies with large sample sizes are warranted to confirm the results of this review. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

In Vivo Evaluation of the Position and Orientation of the Geometric Axis of the Tibiotalar Joint.

Background: Fitting the surface morphology of the talar trochlea is one of the common methods to define the geometric axis of the tibiotalar joint (GATJ). However, the in vivo motion of such axis during gait has not been fully investigated. Methods: The ankle kinematic data of fifteen volunteers were collected by a dual fluoroscopic imaging system with a model-image registration method. The GATJ was defined by sphere-fitting the medial or lateral part of the trochlear surface of the talus. The position and orientation of this axis during gait were measured. To verify this axis, the distances of the feature points of the talus to the GATJ during gait were also measured. Results: There was no statistically significant difference in the distances of feature points of the talus to the GATJ among the seven key poses of the gait cycle. And the position and orientation of the GATJ during gait also showed no statistically significant difference. Conclusion: The GATJ is the axis about which the talus rotated. And it is one fixed axis during gait. The current finding may help the design of the talar component for total ankle replacement based on the surface morphology of the talar trochlea.

Percutaneous Inferior Extensor Retinaculum Augmentation Technique for Chronic Ankle Instability.

OBJECTIVE: To specify indications and contraindications of the modified percutaneous inferior extensor retinaculum augmentation (PIERA) technique for chronic ankle instability cases, and to introduce technique details and report surgical outcomes and complications. METHODS: The PIERA technique was performed on seven patients with chronic ankle instability (four females and three males, 36.4 ± 15.1 years of age, and course of symptoms of 33.7 ± 8.8 months) from June to October 2018 in this retrospective study of case series. All patients demonstrated attenuated ligamentous tissue quality, which was confirmed using preoperative ankle MRI. IER were drew up to the distal fibula using suture anchors with the ankle in neutral position for all cases, to engage the entire IER in reconstructing the stability of the ankle. Patients were assessed using American Orthopaedic Foot and Ankle Society Ankle-Hindfoot (AOFAS) score and Cumberland Ankle Instability Tool (CAIT) scores pre- and postoperatively at the last follow-up examination. Preoperative and postoperative outcome scores of patients were compared using paired t-test. A p value of less than 0.05 was regarded statistically significant. RESULTS: Mean follow-up duration was 16.7 ± 1.6 months. The mean AOFAS score significantly improved from 66.9 ± 11.2 preoperatively to 93.7 ± 8.5 postoperatively (P = 0.001). Mean CAIT score significantly improved from 13.1 ± 4.7 preoperatively to 26.3 ± 1.8 postoperatively (P = 0.001). Patients did not report any wound healing problem, numbness, swelling, or instability at the last follow-up examination, except for one patient who reported pain and minimal stiffness, and presented an AOFAS score of less than 80 and a CAIT score below 24. All patients returned to at least recreational sport activity level. CONCLUSION: The PIERA technique can improve the functional outcomes of patients with chronic ankle instability with few complications.

Quantitative analysis with load-displacement ratio measured via digital arthrometer in the diagnostic evaluation of chronic ankle instability: a cross-sectional study.

BACKGROUND: Arthrometry has been introduced to evaluate the laxity of ankle joint in recent years. However, its role in the diagnosis of chronic ankle instability is still debatable. Therefore, we assessed the diagnostic accuracy of a digital arthrometer in terms of sensitivity and specificity. METHODS: According to the inclusion and exclusion criteria proposed by the International Ankle Consortium, we recruited 160 uninjured ankles (control group) and 153 ankles with chronic ankle instability (CAI group). Ankle laxity was quantitively measured by a validated digital arthrometer. Data of loading force and joint displacement were recorded in a continuous manner. Differences between the control and CAI groups were compared using 2-tailed independent t test. A receiver operating characteristic curve analysis was used to calculate area under a curve, sensitivity and specificity. RESULTS: Load-displacement curves of the two groups were depicted. Differences of joint displacement between the control and CAI groups were compared at 30, 45, 60, 75, 90, 105 and 120 N, which were all of statistical significance (all p < 0.001) with the largest effect size at 90 N. Statistical significance was found in the differences between the two groups in load-displacement ratio at 10-120 N, 10-40 N, 40-80 N and 80-120 N (all p < 0.001), with the largest effect size at 10-40 N. Load-displacement ratio at the interval of 10-40 N had the highest area under a curve (0.9226), with sensitivity and specificity of 0.804 and 0.863, respectively, when the cutoff point was 0.1582 mm/N. CONCLUSION: The digital arthrometer measurement could quantitively analyze the ankle laxity with high diagnostic accuracy. The load-displacement ratio would be a reliable and promising approach for chronic ankle instability diagnosis. Level of evidence level II.

Concomitant osteochondral lesions of the talus affect the stair descent biomechanics of patients with chronic ankle instability: A pilot study.

BACKGROUND: Previous studies on the kinematics of patients with chronic ankle instability (CAI) that did not incorporate MRI and arthroscopic assessment could not differentiate between patients with CAI without osteochondral lesion of the talus (OLT) and patients with CAI and OLT and have thus presented contradictory results. RESEARCH QUESTION: This study aimed to investigate the kinematic and electromyographic differences between patients with and without OLT. METHODS: Sixteen subjects with CAI (eight without OLT and eight with OLT confirmed through MRI and arthroscopic assessment) and eight healthy subjects underwent gait analysis in a stair descent setting. The three groups' patient-reported outcomes; ankle joint range of motion in flexion, inversion and rotation; and muscle activation of the peroneus, tibialis anterior, and gastrocnemius during a gait cycle were analyzed and compared. A curve analysis, namely, one-dimensional statistical parametric mapping, was performed to compare the dynamic ankle kinematics and muscle activation curves over the entire normalized time series. RESULTS: The patients with and without OLT had no difference in patient-reported outcomes. The maximal ankle plantarflexion of the patients without OLT and the healthy subjects was significantly larger than that of patients with OLT (p = 0.005). The maximal ankle internal rotation of patients without OLT was significantly larger than that of patients with OLT (p = 0.048). The peroneal activation during 0-6% of the gait cycle of patients with OLT was reduced compared with the healthy subjects. SIGNIFICANCE: Patients with CAI and OLT and patients with CAI without OLT have no difference in patient-reported outcomes, but patients with OLT can be differentiated using the post-initial-contact peroneal activation deficit and the restriction of ankle plantarflexion and internal rotation during stair descent. These variables can be utilized to monitor the function of patients with CAI and their possibility of developing OLT.

Dynamic Reach Deficit Is a Predictive Factor of Inferior Outcomes After Modified Broström Procedure for Lateral Ankle Instability.

BACKGROUND: Only a few studies have analyzed functional predictive factors for inferior outcomes after modified Broström procedure (MBP). The aim of the current study is to identify the influence of the preoperative dynamic reach deficit on the surgical outcomes of MBP. METHODS: Sixty-one patients with lateral ankle instability who underwent MBP were included in the current study and followed up for a median of 24 months. The Karlsson scores and the reaches of the Star Excursion Balance Test (SEBT) were evaluated before surgery and during the last follow-up. A total of 19 prognostic factors were analyzed. The relationship between the variables and inferior outcomes (Karlsson score < 90) in the bivariate analysis was tested through the Mann-Whitney U test or the Fisher exact test. A multivariate logistic regression model was developed to investigate the influence of the selected factors on inferior outcomes. RESULTS: Thirty-two of the patients had superior outcomes, and the rest had inferior outcomes. The age, gender, and body mass index of the groups with superior and inferior outcomes did not differ. Preoperative dynamic reach deficit (P = .032), osteochondral lesion of the talus (P = .004), and decreased preoperative Karlsson score (P = .004) were independent predictors of inferior outcomes. CONCLUSION: Patients with preoperative dynamic reach deficit, osteochondral lesion of the talus, or decreased preoperative Karlsson score have inferior outcomes after MBP. LEVEL OF EVIDENCE: Level III, case-control study.

Epidemiological Characteristics of Patients Operated for Achilles Tendon Rupture in Shanghai.

OBJECTIVE: To reflect the potential epidemiological characteristics of Achilles tendon (AT) rupture in Shanghai, China, which has been rarely reported before. METHODS: This work is a descriptive epidemiology study. A total of 302 cases of AT rupture admitted to our department between 01/2013 and 02/2020 are analyzed according to telephone follow-up and medical records. Male to female ratio is 10.3 and the average age is 37.5 years. The record of each case includes age, gender, Body mass index (BMI), quinolone use, corticoid exposure and related medical history/comorbidities. If the case is sports-related (SR), details including kind of sports, intensity of exercise, exercise time before rupture, specific action that causes rupture and situation of warm-up are collected. Two independent sample t-tests and Pearson chi-square tests are used for statistical analysis. RESULTS: A total of 252 ruptures are SR. Male to female ratio is 15.6 in SR cases. Most SR ruptures occur in patients aged 25-39 years. Ball games are major sports responsible for rupture: basketball in 95 (37.7%), badminton in 68 (27.0%) and soccer in 62 (24.6%). Acceleration and running start is the specific action that cause most (37.7%) ruptures. AT cases are observed in 91 patients with warm-up and 161 without preparation before exercise. As a result, more ruptures happened within 10 min' sports in 161 unprepared (22.4%) than in 91 prepared (5.5%) cases. In SR cases, 107 and 145 cases are observed on weekends and weekdays. Of the 302 total cases, 64 are associated with Achilles tendinopathy. Frequently reported factors such as quinolone use and corticoid exposure are found only in two and 11 of all cases, respectively. CONCLUSION: Middle-aged males are common victims of AT rupture in Shanghai. Sports including basketball, badminton, soccer and actions involving in sudden and severe contraction of AT cause most ruptures. Warm-up before exercise reduces rupture in short time. Factors such as quinolone, corticoid and Achilles tendonitis still need attention.