diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 0c2bb4543ba8..c807836f3dab 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -32,9 +32,6 @@ updates:
       - dependency-name: "org.apache.lucene:lucene-queries"
         versions:
           - ">= 6.0"
-      - dependency-name: "org.apache.lucene:lucene-backward-codecs"
-        versions:
-          - ">= 6.0"
       - dependency-name: "org.apache.lucene:lucene-analyzers-phonetic"
         versions:
           - ">= 6.0"
diff --git a/api/src/main/java/org/openmrs/api/context/Context.java b/api/src/main/java/org/openmrs/api/context/Context.java
index ffb1e5185bc0..f0201bc836a1 100644
--- a/api/src/main/java/org/openmrs/api/context/Context.java
+++ b/api/src/main/java/org/openmrs/api/context/Context.java
@@ -61,6 +61,7 @@
 import org.openmrs.util.DatabaseUpdater;
 import org.openmrs.util.InputRequiredException;
 import org.openmrs.util.LocaleUtility;
+import org.openmrs.util.LuceneIndexUpgrader;
 import org.openmrs.util.OpenmrsClassLoader;
 import org.openmrs.util.OpenmrsConstants;
 import org.openmrs.util.OpenmrsUtil;
@@ -1017,6 +1018,16 @@ public static synchronized void startup(Properties props) throws DatabaseUpdateE
 		// data directory can be set from the runtime properties
 		OpenmrsUtil.startup(props);
 
+		// Upgrade Lucene indexes if needed before any database operations
+		// This addresses TRUNK-5731 by ensuring old Lucene410 indexes are upgraded
+		// before Hibernate Search tries to read them
+		try {
+			LuceneIndexUpgrader.upgradeLuceneIndexesIfNeeded(props);
+		} catch (Exception e) {
+			log.warn("Failed to upgrade Lucene indexes during startup: {}", e.getMessage());
+			// Don't fail startup for Lucene index upgrade issues, but log the warning
+		}
+
 		openSession();
 		clearSession();
 
diff --git a/api/src/main/java/org/openmrs/util/LuceneIndexUpgrader.java b/api/src/main/java/org/openmrs/util/LuceneIndexUpgrader.java
new file mode 100644
index 000000000000..4a12f841f2cf
--- /dev/null
+++ b/api/src/main/java/org/openmrs/util/LuceneIndexUpgrader.java
@@ -0,0 +1,139 @@
+/**
+ * This Source Code Form is subject to the terms of the Mozilla Public License,
+ * v. 2.0. If a copy of the MPL was not distributed with this file, You can
+ * obtain one at http://mozilla.org/MPL/2.0/. OpenMRS is also distributed under
+ * the terms of the Healthcare Disclaimer located at http://openmrs.org/license.
+ *
+ * Copyright (C) OpenMRS Inc. OpenMRS is a registered trademark and the OpenMRS
+ * graphic logo is a trademark of OpenMRS Inc.
+ */
+package org.openmrs.util;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Properties;
+
+import org.apache.lucene.index.DirectoryReader;
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.store.Directory;
+import org.apache.lucene.store.FSDirectory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Utility class to handle Lucene index upgrades during OpenMRS startup. This addresses TRUNK-5731
+ * by ensuring Lucene indexes are upgraded before any database operations that might try to read
+ * them.
+ * 
+ * @since 2.4.0
+ */
+public class LuceneIndexUpgrader {
+	
+	private static final Logger log = LoggerFactory.getLogger(LuceneIndexUpgrader.class);
+	
+	/**
+	 * Upgrades Lucene indexes if they exist and are using old codecs. This method should be called
+	 * before any database operations during startup.
+	 * 
+	 * @param properties Runtime properties containing application data directory
+	 * @return true if upgrade was performed, false if no upgrade was needed
+	 */
+	public static boolean upgradeLuceneIndexesIfNeeded(Properties properties) {
+		String appDataDir = properties.getProperty(OpenmrsConstants.KEY_OPENMRS_APPLICATION_DATA_DIRECTORY);
+		if (appDataDir == null || appDataDir.trim().isEmpty()) {
+			log.debug("No application data directory specified, skipping Lucene index upgrade check");
+			return false;
+		}
+		
+		Path luceneIndexDir = Paths.get(appDataDir, "lucene", "indexes");
+		if (!Files.exists(luceneIndexDir)) {
+			log.debug("Lucene index directory does not exist: {}", luceneIndexDir);
+			return false;
+		}
+		
+		log.info("Checking for Lucene index upgrade requirements in: {}", luceneIndexDir);
+		
+		boolean upgradePerformed = false;
+		try {
+			// Check each subdirectory in the lucene indexes directory
+			Files.list(luceneIndexDir)
+				.filter(Files::isDirectory)
+				.forEach(indexPath -> {
+					try {
+						if (needsUpgrade(indexPath)) {
+							log.info("Upgrading Lucene index: {}", indexPath);
+							upgradeIndex(indexPath);
+						}
+					} catch (Exception e) {
+						log.warn("Failed to upgrade Lucene index at {}: {}", indexPath, e.getMessage());
+						// Continue with other indexes even if one fails
+					}
+				});
+		} catch (IOException e) {
+			log.warn("Failed to list Lucene index directories: {}", e.getMessage());
+		}
+		
+		return upgradePerformed;
+	}
+	
+	/**
+	 * Checks if a Lucene index needs upgrading by attempting to read it. If it fails with a
+	 * codec-related error, it needs upgrading.
+	 * 
+	 * @param indexPath Path to the Lucene index
+	 * @return true if the index needs upgrading
+	 */
+	private static boolean needsUpgrade(Path indexPath) {
+		try (Directory directory = FSDirectory.open(indexPath)) {
+			// Try to open the index with current Lucene version
+			try (IndexReader reader = DirectoryReader.open(directory)) {
+				// If we can open it successfully, no upgrade needed
+				log.debug("Lucene index at {} is already compatible", indexPath);
+				return false;
+			}
+		} catch (Exception e) {
+			// Check if this is a codec-related error
+			String errorMessage = e.getMessage();
+			if (errorMessage != null && 
+				(errorMessage.contains("Lucene410") || 
+				 errorMessage.contains("does not exist") ||
+				 errorMessage.contains("codec"))) {
+				log.info("Lucene index at {} needs upgrading: {}", indexPath, errorMessage);
+				return true;
+			} else {
+				log.debug("Lucene index at {} has a different error (not codec-related): {}", indexPath, errorMessage);
+				return false;
+			}
+		}
+	}
+	
+	/**
+	 * Upgrades a Lucene index by deleting the old index files. This forces Hibernate Search to
+	 * recreate the index with the current codec.
+	 * 
+	 * @param indexPath Path to the Lucene index to upgrade
+	 */
+	private static void upgradeIndex(Path indexPath) {
+		try {
+			log.info("Deleting old Lucene index files at {} to force recreation with current codec", indexPath);
+			
+			// Delete all files in the index directory
+			Files.list(indexPath)
+				.forEach(file -> {
+					try {
+						Files.delete(file);
+						log.debug("Deleted index file: {}", file);
+					} catch (IOException e) {
+						log.warn("Failed to delete index file {}: {}", file, e.getMessage());
+					}
+				});
+			
+			log.info("Successfully upgraded Lucene index at {}", indexPath);
+		} catch (IOException e) {
+			log.error("Failed to upgrade Lucene index at {}: {}", indexPath, e.getMessage());
+			throw new RuntimeException("Failed to upgrade Lucene index", e);
+		}
+	}
+}
diff --git a/api/src/test/java/org/openmrs/util/LuceneIndexUpgraderTest.java b/api/src/test/java/org/openmrs/util/LuceneIndexUpgraderTest.java
new file mode 100644
index 000000000000..de9565245b15
--- /dev/null
+++ b/api/src/test/java/org/openmrs/util/LuceneIndexUpgraderTest.java
@@ -0,0 +1,77 @@
+/**
+ * This Source Code Form is subject to the terms of the Mozilla Public License,
+ * v. 2.0. If a copy of the MPL was not distributed with this file, You can
+ * obtain one at http://mozilla.org/MPL/2.0/. OpenMRS is also distributed under
+ * the terms of the Healthcare Disclaimer located at http://openmrs.org/license.
+ *
+ * Copyright (C) OpenMRS Inc. OpenMRS is a registered trademark and the OpenMRS
+ * graphic logo is a trademark of OpenMRS Inc.
+ */
+package org.openmrs.util;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Properties;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+/**
+ * Tests for {@link LuceneIndexUpgrader}
+ * 
+ * @since 2.4.0
+ */
+public class LuceneIndexUpgraderTest {
+	
+	@TempDir
+	Path tempDir;
+	
+	@Test
+	public void upgradeLuceneIndexesIfNeeded_shouldReturnFalseWhenNoAppDataDir() {
+		Properties props = new Properties();
+		// No application data directory set
+		
+		boolean result = LuceneIndexUpgrader.upgradeLuceneIndexesIfNeeded(props);
+		
+		assertFalse(result);
+	}
+	
+	@Test
+	public void upgradeLuceneIndexesIfNeeded_shouldReturnFalseWhenLuceneDirDoesNotExist() throws IOException {
+		Properties props = new Properties();
+		props.setProperty(OpenmrsConstants.KEY_OPENMRS_APPLICATION_DATA_DIRECTORY, tempDir.toString());
+		
+		boolean result = LuceneIndexUpgrader.upgradeLuceneIndexesIfNeeded(props);
+		
+		assertFalse(result);
+	}
+	
+	@Test
+	public void upgradeLuceneIndexesIfNeeded_shouldReturnFalseWhenLuceneDirExistsButEmpty() throws IOException {
+		Properties props = new Properties();
+		props.setProperty(OpenmrsConstants.KEY_OPENMRS_APPLICATION_DATA_DIRECTORY, tempDir.toString());
+		
+		// Create lucene directory but leave it empty
+		Path luceneDir = tempDir.resolve("lucene").resolve("indexes");
+		Files.createDirectories(luceneDir);
+		
+		boolean result = LuceneIndexUpgrader.upgradeLuceneIndexesIfNeeded(props);
+		
+		assertFalse(result);
+	}
+	
+	@Test
+	public void upgradeLuceneIndexesIfNeeded_shouldHandleNonExistentAppDataDir() {
+		Properties props = new Properties();
+		props.setProperty(OpenmrsConstants.KEY_OPENMRS_APPLICATION_DATA_DIRECTORY, "/nonexistent/path");
+		
+		// Should not throw exception, just return false
+		boolean result = LuceneIndexUpgrader.upgradeLuceneIndexesIfNeeded(props);
+		
+		assertFalse(result);
+	}
+}