diff --git a/pymupdf4llm/pymupdf4llm/helpers/__pycache__/get_text_lines.cpython-312-pytest-8.3.4.pyc b/pymupdf4llm/pymupdf4llm/helpers/__pycache__/get_text_lines.cpython-312-pytest-8.3.4.pyc
new file mode 100644
index 00000000..9aa2b4c3
Binary files /dev/null and b/pymupdf4llm/pymupdf4llm/helpers/__pycache__/get_text_lines.cpython-312-pytest-8.3.4.pyc differ
diff --git a/pymupdf4llm/pymupdf4llm/helpers/get_text_lines.py b/pymupdf4llm/pymupdf4llm/helpers/get_text_lines.py
index 8af6a1e8..171ad7f7 100644
--- a/pymupdf4llm/pymupdf4llm/helpers/get_text_lines.py
+++ b/pymupdf4llm/pymupdf4llm/helpers/get_text_lines.py
@@ -110,10 +110,11 @@ def sanitize_spans(line):
                     continue
                 if s["flags"] & 1 == 1:  # if a superscript, modify bbox
                     # with that of the preceding or following span
-                    i = 1 if sno == 0 else sno - 1
-                    neighbor = line["spans"][i]
-                    sbbox.y1 = neighbor["bbox"][3]
-                    s["text"] = f"[{s['text']}]"
+                    if len(line["spans"]) > 1:
+                        i = 1 if sno == 0 else sno - 1
+                        neighbor = line["spans"][i]
+                        sbbox.y1 = neighbor["bbox"][3]
+                        s["text"] = f"[{s['text']}]"
                 s["bbox"] = sbbox  # update with the Rect version
                 # include line/block numbers to facilitate separator insertion
                 s["line"] = lno
diff --git a/tests/pymupdf4llm/llama_index/__pycache__/test_pdf_markdown_reader.cpython-312-pytest-8.3.4.pyc b/tests/pymupdf4llm/llama_index/__pycache__/test_pdf_markdown_reader.cpython-312-pytest-8.3.4.pyc
new file mode 100644
index 00000000..d731ca5c
Binary files /dev/null and b/tests/pymupdf4llm/llama_index/__pycache__/test_pdf_markdown_reader.cpython-312-pytest-8.3.4.pyc differ