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.

Background: This study is a retrospective review of prospectively gathered data determining the postoperative outcomes of patients who underwent operative treatment to address chronic syndesmotic instability. Methods: The cohort is composed of 19 individuals who elected to undergo operative treatment of chronic syndesmotic instability. The operative repair consisted of arthroscopic debridement in all cases with reduction and suture button fixation of those patients who had greater than 4 mm of syndesmotic diastasis on arthroscopic evaluation. All patients had a minimum of 24 months follow-up. This study retrospectively examined the prospectively gathered preoperative and postoperative outcome scores to include a Visual Analog Scale (VAS) pain score and an American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score. In addition, patients were questioned on their ability to return to their preinjury level of activity and their ability to continue running sports. Fourteen patients returned their postoperative surveys. Results: Mean AOFAS scores improved significantly from 48 to 82.7 (P = .014). Mean VAS scores improved from 6.1 to 1.0 (P = .002). Overall, 86% (12/14) of patients were able to return to running and 79% (11/14) of patients were able to return to their preinjury level of sport. Preoperative and postoperative weight-bearing ankle radiographs were reviewed to evaluate the tibiofibular clear space and overlap. The clear space measured on anteroposterior (AP) radiographs decreased from 5.4 mm to 4.6 mm (P = .005), the clear space evaluated on the mortise radiograph decreased from 4.5 mm to 3.6 mm (P = .006), and the overlap measured on the AP radiograph increased from 5.7 mm to 6.9 mm (P = .019). All radiographs were measured by a board-certified musculoskeletal radiologist. Conclusion: This study presents a treatment method that can be instituted at the time of diagnosis for syndesmotic injuries with greater than 4 mm of diastasis that were treated with debridement and stabilization. The results of this treatment technique are promising, with significant improvements in subjective outcome scores and a high rate of return to running sports. Level of Evidence: Level IV, retrospective case series.

Background: Latent syndesmotic instability is a common cause of chronic ankle pain. The diagnosis is not readily apparent on static imaging as the fibula remains reduced. The hypothesis of this study was that a previously undescribed novel finding on coronal MRI (lambda sign) is an independent indicator of latent syndesmosis instability. We also report on the utility of classic radiographic and physical exam findings. Methods: A total of 23 patients with latent syndesmotic instability diagnosed via arthroscopy (group I) were compared to a cohort of 40 patients who were found to have a stable syndesmosis during arthroscopy for unrelated conditions (group II). A retrospective chart review was performed evaluating their clinical history, preoperative physical examination, and radiologic findings. The lambda sign is a high intensity signal seen on coronal MR imaging that resembles the Greek letter lambda. Results: All of the physical exam findings tested were statistically significant. Pain at the syndesmosis had the highest sensitivity (83%), while pain reproduced with the proximal squeeze test resulted in the highest specificity (89%). The external rotation stress test had the highest positive predictive value (75%). Of the radiographic examinations performed, only the lambda sign was found to have statistical significance with a sensitivity of 75% and a specificity of 63%. The presence of a lambda sign on the MRI of patients with physical exam findings suggestive of syndesmotic pain was highly sensitive (75%) and specific (85%). Conclusion: The lambda sign noted on the coronal MRI was both sensitive and specific for injuries involving greater than 2 mm of diastasis on arthroscopic stress examination of the syndesmosis. While neither the lambda sign nor any other finding on physical or radiographic examination represented an independent predictor of syndesmotic instability, the presence of a lambda sign in concert with positive physical exam findings might help health care providers determine which patients might benefit from operative intervention or referral. Level of Evidence: Level III, case control study.

Background: The treatment of osteochondral lesions of the talus (OLTs) with a juvenile cartilage allograft is a relatively new procedure. Although other treatment options exist for large OLTs, the potential advantage of a particulated juvenile allograft is the ability to perform the procedure arthroscopically or through a minimal approach. No previous studies have looked at the results of an arthroscopic approach, nor have any compared an arthroscopic technique with an open approach. Purpose: To compare the outcomes of an arthroscopic transfer technique with the previously published open technique. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 34 patients (mean age, 33 years) underwent treatment of talar cartilage lesions with a DeNovo NT Natural Tissue Graft. Of these treatments, 20 were performed arthroscopically and 14 were performed with open arthrotomy. There was no statistically significant difference between the groups with respect to age, lesion width, lesion depth, lesion length, or operative time. The mean lesion area was 107 mm². The scores from 6 different validated outcome measures were recorded for patients in each group preoperatively and subsequently at 6 months, 1 year, 18 months, and 2 years. Results: Comparing outcome scores at each time point to baseline, there were no statistically significant postoperative differences found between open and arthroscopic approaches with regard to the visual analog scale (VAS) for pain ( P = .09), American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale ( P = .17), Foot and Ankle Ability Measure (FAAM)–sports subscale ( P = .73), Short Form–12 (SF-12) physical health summary ( P = .85), SF-12 mental health summary ( P = .91), or FAAM–activities of daily living subscale ( P = .76). Conclusion: The treatment of talar articular cartilage lesions with a DeNovo NT Natural Tissue Graft demonstrated no significant differences in outcome at 2 years regardless of whether the graft was inserted with an arthroscopic or open technique. Clinical Relevance: Our analysis demonstrated no significant difference between an arthroscopic versus open approach at any time point for the first 2 years after implantation of a juvenile particulated cartilage allograft for large OLTs. With that said, both groups demonstrated improvement from baseline. These findings indicate that surgeons with different levels of comfort utilizing arthroscopic techniques can offer this treatment modality to their patients without altering their planned surgical approach. In addition, this will be particularly helpful in counseling patients for surgery when the extent of the defect will be evaluated intraoperatively. Patients can be counseled that they will likely have the same incisions regardless of whether they require debridement, microfracture, or implantation of a particulated allograft.

Latent or subtle syndesmotic instability is defined as an injury to the syndesmosis which is not apparent on static radiographs of the ankle. Syndesmotic injuries have also been referred to as high ankle sprains. Injury to the syndesmosis typically occurs with collision sports and often involves an external rotation force to the ankle. Diagnosis can be delayed because of negative initial imaging studies. Physical examination tests including the external rotation test, proximal squeeze test, and fibular shuck test can assist in the diagnosis. Advanced imaging modalities such as MRI and weight-bearing CT have been studied and can provide prognostic indications for management, although arthroscopic stress evaluation remains the benchmark for diagnosis. Both surgical and nonsurgical management techniques have been described, which can assist patients in returning to their preinjury level of function.