Immediate weight bearing without immobilization for operatively treated ankle fractures is safe - A systematic review.

BACKGROUND: This systematic literature review compared weight bearing (WB) vs. partial- / non-weight bearing (NWB) and mobilization (MB) vs. immobilization (IMB) for surgically treated ankle fractures. METHODS: Five databases were searched. Eligible were (quasi-)randomized controlled trials comparing at least two different postoperative treatment protocols. The risk of bias was assessed using the RoB-2 toolkit. The primary outcome was complication rate, secondary outcome Olerud and Molander Ankle Score (OMAS), range of motion (ROM), and return to work (RTW). RESULTS: Out of 10,345 studies, 24 papers were eligible. Thirteen studies (n = 853) compared WB/NWB, 13 studies (n = 706) MB/IMB with a moderate study quality. WB did not increase the risk for complications but resulted in superior short-term outcomes for OMAS, ROM, RTW. 12 studies found no inferior results for MB compared to IMB. CONCLUSION: Early and immediate WB and MB do not increase the complication rates but result in superior short term outcome scores. LEVEL OF EVIDENCE: Level I Systematic Review.

Safe drilling zones for anteriorly, central, and posteriorly angulated syndesmotic stabilization devices.

PURPOSE: The purposes of the study were to (1) analyze the shape of the distal fibula at the location of syndesmotic stabilization and to (2) define safe zones at the distal-lateral fibula for three different drilling tunnel orientations: anteriorly-, posteriorly angulated and center-center. METHODS: Postoperative, bilateral CT images of adult patients that underwent syndesmotic stabilization (suture-button system) for an acute, unilateral ankle injury were analyzed. Manual axial CT reconstructions of the uninjured side were generated. First, the axial shape of the distal fibula was classified. The aspect ratio between the anterio-lateral and the posterior-lateral surfaces of the fibula was calculated to assess symmetry. Second, the same axial planes were used to define the safe zones. Each drilling-tunnel orientation (anterior, central, posterior) comprised a fixed medial tibial anchor point and a safe zone on the lateral fibula. For each of the three orientations, the most anteriorly and posteriorly drilling tunnel location was simulated. Next to a cumulative visual analysis, a quantitative analysis of the most anterior and posterior point on the anterio- and posterior-lateral surfaces was calculated. RESULTS: A total of 96 CT datasets were analyzed. (1) 81% of fibulae revealed a triangular convex-, 10% an irregular-, and 8% a quadrilateral shape. The lateral surface ratio was 1.0 ± 0.2 (range: 0.7-1.5), not differing between the fibula types (n.s.). (2) The safe corridor on the lateral surface of the fibula for an anteriorly angulated drilling tunnel was - 8% to - 41%, for a posteriorly angulated drilling tunnel was 0% to 46%, and for a center-center alignment - 7 ± 11% (range: - 28 to 18%). CONCLUSION: The meta-diaphyseal region of the distal fibula revealed a homogeneous crosssectional shape. The lateral apex of the fibula can serve as a landmark defining safe zones to place the drilling tunnels correctly. Applying these safe zones in clinical practice could help to avoid the misplacement of the syndesmotic fixation device. LEVEL OF EVIDENCE: Level III, retrospective radiographic study.

A systematic review and meta-analysis on the value of the external rotation stress test under fluoroscopy to detect syndesmotic injuries.

Purpose: The aim was to conduct a systematic literature review and meta-anaylsis to analyze the diagnostic accuracy of the external rotation stress test (ERST) for syndesmotic injuries. Methods: The systematic review was conducted according to the PRISMA-P guidelines (Prospero ID: CRD42021282457). Four common databases were searched from inception to September 29, 2021. Eligible were any studies facilitating the ERST under fluoroscopy in a defined state of syndesmotic instability. Syndesmotic ligament-specific rupture must have been proven by MRI, arthroscopy, or controlled dissection (cadaver study). Two reviewers independently conducted each step of the systematic literature review. The risk of bias was assessed by the Quality Appraisal for Cadaveric Studies Score scale. The data analysis was performed qualitatively and quantitatively. Results: Eight studies were eligible for a qualitative analysis, and six studies were eligible for a quantitative analysis. All studies included were cadaver studies. The qualitative analysis comprised 94 specimens and revealed considerable heterogeneity. Six studies allowed for a quantitative analysis of the tibiofibular clear space (TFCS) and five studies for the medial clear space (MCS) during the ERST. The quantitative analysis of the TFCS revealed no significant differences between intact and any stage of syndesmotic injury. The MCS was able to differentiate between intact and 2-ligament- (Z = 2.04, P = 0.02), 3-ligament- (Z = 3.2, P = 0.001), and 3-ligament + deltoid ruptures (Z = 3.35, P < 0.001). Conclusion: The ERST is the only noninvasive test to assess syndesmotic instability and can be conducted bilaterally. The uninjured contralateral side can serve as a baseline reference. Based on the conducted quantitative analysis, the MCS seems to be able to differentiate between stable (intact/1-ligament) and unstable (2-ligament/3-ligament) lesions.