Is there a Relationship between Bone Morphology and Injured Ligament on Imaging Studies and Laxity on Ankle Stress Radiographs?

Skeletal Features of Talus in Hepple V Lesion

The present study was to determine the characteristics of the ankle skeletal structure in patients with talus Hepple V type. We conducted a retrospective study on the skeletal structure of the talus in 110 patients with Hepple V osteochondral lesions of the talus and in control participants. The radiographic measurements taken include the following: in the coronal plane - depth of talus frontal curvature, length of the lateral and medial malleolus; in the sagittal plane - radius and height of talus, angle of tibial lateral surface, tibiotalar sector, and vertical neck angle. The osteochondral lesion of the talus showed a significantly larger mean radius (mean ± SD, 21.4 ± 2.5 mm; p < .001) and height (mean ± SD, 26.0 ± 2.7 mm; p < .005). It also demonstrated a longer mean medial malleolus length (mean ± SD, 15.7 ± 2.4 mm; p < .005), a larger mean vertical neck angle (mean ± SD, 86.2 ± 5.4°; p < .050), and a greater mean tibial lateral surface angle (mean ± SD, 80.0 ± 4.5°; p < .001). And there was a greater mean frontal curvature depth (mean ± SD, 3.9 ± 0.6 mm; p < .005). Overall, this study found that patients with Hepple V osteochondral lesions of the talus had a larger vertical neck angle and tibial lateral surface angle, a longer talus radius and medial malleolus length, a higher talus height, and a deeper frontal curvature depth. STUDY DESIGNS: Retrospective Case-Control Study.

Can Anatomical Differences Contribute to the Etiology of Danis-Weber Type B Lateral Malleolus Fractures?

Introduction Lateral malleolus fractures are among the most common ankle fractures, but the anatomical factors that may predispose individuals to this specific type of fracture are not fully understood. This study aims to explore whether distinct anatomical characteristics of the ankle joint contribute to an increased susceptibility to lateral malleolar fractures. Methods A retrospective analysis was conducted on 73 patients diagnosed with isolated lateral malleolar fractures between 2020 and 2023. An array of radiologic parameters, including distal tibial articular surface (DTAS) angle, bimalleolar tilt (BMT), medial malleolar length (MML), lateral malleolar length (LML), medial malleolar relative length (MMRL), lateral malleolar relative length (LMRL), medial malleolar slip angle (MMSA), talocrural angle (TCA), anterior inclination of the tibia (AI), and fibular position (FP), were meticulously measured on anteroposterior and lateral ankle radiographs for each study participant. We also measured the same parameters in 126 individuals who had not experienced an ankle fracture for comparison. Results Statistically significant differences were observed between the fracture group and the control group for DTAS angle, BMT, MML, MMRL, LMRL, TCA, AI, and FP (p<.05). Conversely, LML and MMSA displayed no significant variations between the two groups (p=0.745 and p=0.623). Effect sizes were notably large for DTAS and TCA, medium for MMRL, BMT, and AI, and small for LMRL, MML, and FP. Conclusion Our findings indicate an increased risk of lateral malleolus fractures in individuals with a relatively longer medial malleolus, a valgus-oriented ankle, reduced anterior inclination of the tibia, and an anteriorly positioned fibula. Taking protective measures during risky activities in individuals with these differences may help to prevent fractures.

Comparison of the effects of reconstruction of the lateral ankle ligaments using peroneus longus and peroneus brevis tendon graft

Peroneus longus and peroneus brevis tendon grafts have been frequently used to reconstruct the lateral ankle ligaments. However, there is no literature comparing the effect of the 2 methods. The purpose of this study was to compare the effects of 2 autologous tendon transplants on ankle joint activity.This retrospective study included 100 adult patients with chronic lateral ankle instability (CLAI) who underwent surgery from January 2014 to December 2017. Group A (50 patients): Reconstruction of the lateral ankle ligaments using the anterior half of peroneus longus tendon graft; Group B (50 patients): Using the anterior half of peroneus brevis tendon graft. Outcomes were assessed by comparing pre- and postoperative AOFAS scores, VAS pain scores, and Karlsson scores, and the radiographic assessment included talar tilt and anterior talar translation. A sensitive dynamometer was used before and after surgery to assess inversion, valgus, plantarflexion, and dorsiflexion strength to evaluate changes in muscle strength in the patients feet.Postoperatively, 88 patients were followed up for 12 to 24 months, including 46 cases in group A and 42 in group B. No severe complications were recorded in the 2 groups. There were significant pre- to post-operative differences between the groups. No significant differences were observed in the postoperative scores and muscle strength changes between the groups. However, the number of patients with decreased valgus strength in group B was statistically significant compared with group A.Both methods can improve the stability of the ankle joint, but the peroneus longus tendon has little effect on the postoperative muscle strength of the foot and should be used as the preferred surgical treatment for the treatment of CLAI.

Stress radiography in the diagnosis and assessment of the outcomes of surgical treatment of chronic anterolateral ankle instability

BACKGROUND

In about 20-40% of patients, damage to the soft tissues surrounding the ankle leads to recurrent and chronic pain with signs of instability of the talus in the tibiofibular fork.

PURPOSE

The aim of the study was to assess the usefulness of stress X-ray images in the diagnosis of long-term outcomes of conservative versus surgical treatment of anterolateral ankle instability.

MATERIAL AND METHODS

Thirty patients with chronic ankle instability (CAI) were recruited for the study. The participants were divided into two groups. The first group consisted of 15 non-operatively treated individuals diagnosed with anterior talofibular ligament (ATFL) damage. The second group consisted of 15 patients who had undergone surgical reconstruction of the ATFL. In both groups of patients, the contralateral normal limb was used as a control. In all patients, anteroposterior and lateral view stress radiographs of both ankles were taken using the TELOS Stress Device (GA - III/E, Hungen, Germany).

RESULTS

Statistical tests showed that the surgically treated patients had a significantly greater ankle stability compared to the non-surgically treated patients (P = 0.001 for talar tilt angle and P = 0.009 for anterior drawer distance). The results obtained in this study indicate that this method can also be used in postoperative assessment of the function of the reconstructed lateral ankle ligaments.

CONCLUSIONS

Stress radiography is a reliable and safe tool for diagnosing CAI. This imaging method is an objective instrument that can be successfully used in postoperative assessment of the function of the reconstructed ATFL.

Assessing mechanical ankle instability via functional 3D stress-MRI - A pilot study

BACKGROUND

Quantitative measurement of the mechanical deficit in chronic ankle instability (CAI) is difficult. Therefore, the distinction between functional (FAI) and mechanical ankle instability (MAI) as well as the evaluation of surgical techniques is difficult. This pilot study uses a novel method of functional 3-dimensional stress ankle-MRI to test its applicability for assessing mechanical ankle instability.

METHODS

We used a custom-built ankle arthrometer that allows a stepless positioning of the foot and an axial in situ loading with up to 500 N combined with a 3-dimensional MRI protocol. We assessed four parameters (3D cartilage contact area (CCA) fibulotalar, tibiotalar horizontal and vertical and intermalleolar distance) under six different conditions (neutral-null, plantarflexion-supination and dorsiflexion-pronation each with and without loading) in n = 10 individuals (7 suffering from MAI and 3 healthy controls).

FINDINGS

The MAI group showed a substantially increased reduction of lateral osseous constraint compared to healthy controls when the foot was positioned in plantarflexion-supination (CCA fibulotalar 69% vs. 30% in controls). The reduction of the weight bearing surface in plantarflexion-supination was also more pronounced (CCA tibiotalar horizontal -49% in MAI vs. -28% in controls).

INTERPRETATION

This novel technique is valuable for assessing mechanical ankle instability in the target population and has a potential clinical benefit for assessing the mechanical deficit of individual patients. Further studies are needed to provide evidence for a possible prognostic value of this novel technique.

Inverse Relationship Between Radiographic Lateral Ankle Instability and Osteochondral Lesions of the Talus in Patients With Ankle Inversion Injuries

BACKGROUND

Insufficient or excessive bony constraint surrounding the talus might contribute to the occurrence of ligamentous injury or bone contusion, respectively, at the time of ankle inversion injuries. This study aimed to investigate the relationship between radiographic lateral ankle instability and osteochondral lesions of the talus (OLT) following ankle inversion injuries.

METHODS

A total of 195 patients (113 men and 83 women; mean age, 38.7 years) with a history of ankle inversion injuries were included in this study. All patients underwent ankle magnetic resonance imaging (MRI) and stress radiography. The tibiotalar tilt angle on varus stress radiograph, anterior translation of the talus on anterior-drawer lateral radiographs, bimalleolar tilt angle, and fibular position were radiographically determined. The radiographic lateral ankle instability was defined as tibiotalar tilt angle ≥10 degrees, and the presence of OLT was confirmed on MR images. The relationship between the radiographic lateral ankle instability and the presence of OLT was statistically analyzed.

RESULTS

The presence of radiographic lateral ankle instability (tibiotalar tilt angle ≥10 degrees) showed an inverse relationship with that of OLT in the chi-squared test (P = .003). An increased tibiotalar tilt angle was associated with lower incidence of OLT (P = .011) in the multiple regression analysis, and the presence of OLT was associated with a decreased tibiotalar tilt angle (P = .016) in the binary logistic regression analysis.

CONCLUSIONS

This study showed an inverse relationship between lateral ankle instability and the development of OLT following ankle inversion injury. The role of bony constraint in the development of sports injuries in the ankle should be considered with these injuries.

LEVEL OF EVIDENCE

Level III, diagnostic, comparative study.

Reconstruction of the lateral ankle ligaments using the anterior half of peroneus longus tendon graft

BACKGROUND

This study aimed to report our institution's experience in the treatment of chronic lateral ankle instability using the anterior half of the peroneus longus tendon (AHPLT) to reconstruct the lateral ligament.

METHODS

This retrospective study included 32 consecutive patients with chronic lateral ankle instability who underwent surgery from January 2013 to December 2014. All patients had failed to resolve with conservative treatment. A total of 32 ankles underwent AHPLT transfer. Patients returned for a clinical and radiologic follow-up evaluation at an average of 28 (range, 24-35) months postoperatively. Outcomes were assessed by comparison of pre- and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) scores, visual analog scale pain scores, and Karlsson scores, and the radiographic assessment including talar tilt and anterior talar translation.

RESULTS

Thirty-two patients (32 ankles) (100%) returned for final evaluation. All patients had an excellent or good outcome on patient subjective self-assessment, pain scores, AOFAS scores, and Karlsson scores at final follow-up. Ankle range of motion was not affected by lateral ankle reconstruction. The talar tilt was significantly reduced from a preoperative mean of 14.1±4.2° to 3.4±1.3° postoperatively (P<.001), and the anterior drawer was significantly reduced from a preoperative mean of 13.8±3.4mm to 3.6±1.5mm after lateral ankle ligamentous reconstruction (P<.001).

CONCLUSIONS

AHPLT transfer to reconstruct the lateral ligament resulted in a high percentage of successful results, with excellent ankle stability and not affected of ankle motion.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Comparison of Magnetic Resonance Imaging and Stress Radiographs in the Evaluation of Chronic Lateral Ankle Instability

BACKGROUND

In patients who develop chronic ankle instability, clinicians often obtain magnetic resonance imaging (MRI) as part of the evaluation prior to operative referral. The purpose of this study was to analyze the diagnostic efficacy of MRI in the diagnosis of chronic lateral ankle instability. Our hypothesis was that magnetic resonance imaging would not be a specific diagnostic tool in the evaluation of chronic lateral ankle instability.

MATERIALS AND METHODS

A retrospective chart review of 187 consecutive patients (190 ankles) was performed. Inclusion criteria for the study group required a primary complaint of instability that required operative repair or reconstruction, a documented clinical evaluation consistent with instability, stress radiographs, and MRI. Stress radiographs and clinical examinations for the study group and a control group were reviewed independently by both a musculoskeletal radiologist and a board-certified orthopaedic foot and ankle surgeon. Predictive values in terms of sensitivity, specificity, and prevalence were performed. In total, 112 patients (115 ankles) were identified who underwent an operative reconstruction of their lateral ligaments with a history, physical examination, and stress radiographs consistent with lateral ankle instability. A control group was selected consisting of 75 patients seen in the foot and ankle clinic with a diagnosis other than lateral ankle instability. Thirty-seven of the patients in the control group had stress radiographs performed in the clinic to rule out instability as part of their evaluation, and this allowed for an evaluation of the efficacy of stress radiographs in addition to MRI. Statistical analysis was performed using predictive values from sensitivity, specificity, and prevalence.

RESULTS

The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) in regards to MRI in the evaluation of patients found to have clinical lateral ankle instability and those who did not had statistical significance. Sensitivity of MRI was 82.6%, specificity was 53.3%, NPV was 66.7%, and PPV was 73%. Since 37 patients in the control group also had stress radiographs, a subanalysis was performed to identify the same values with stress radiographs. Sensitivity, specificity, NPV, and PPV were 66%, 97%, 48%, and 98.7%, respectively. The overall accuracy within this study was 71% for MRI and 74% for stress radiographs.

CONCLUSION

This study demonstrated that MRI has high sensitivity but low specificity in the evaluation of clinical ankle instability. While MRI has value as a screening tool for concomitant ankle pathology, it should not be considered diagnostic in terms of lateral ankle instability.

LEVEL OF EVIDENCE

Level III, retrospective cohort, comparative series.