Background: Hallux rigidus (HR) is a common forefoot disorder, and surgical treatment is typically guided by the severity of the condition, as defined by the Coughlin and Shurnas four-grade classification. This study aimed to compare clinical and functional outcomes in patients undergoing first metatarsophalangeal joint arthrodesis (FMTPJA) with or without the use of an interfragmentary (IF) screw in addition to a dorsal plate. Methods: We retrospectively evaluated a cohort of patients who underwent surgery with a FMTPJA, dividing patients in two groups: patients who underwent FMTPJA through dorsal plate associated with an interfragmentary screw (WIS group) and patients who underwent FMTPJA through dorsal plate without an interfragmentary screw (WOIS group). The primary outcomes were analyzed using the FAAM score and FAAM sport score. Secondary outcomes included VAS, patient satisfaction, recovery time to return to sports, and the level of postoperative sports activity compared to preoperative levels. Results: In paired analyses, the WOIS group showed statistically significant improvements in both the FAAM and FAAM sport scores (p = 0.01). In contrast, the WIS group showed significant improvement only in the FAAM sport score (p = 0.01), while the FAAM score did not reach statistical significance (p = 0.42). Multivariate analysis revealed that a higher preoperative FAAM score predicted a higher postoperative FAAM score (p = 0.75), while the use of an IF screw was associated with a lower expected postoperative FAAM score (p = 0.25). Increased BMI and older age were significantly associated with lower postoperative FAAM scores. Conclusions: Both surgical techniques led to significant clinical improvements. However, patients in the WOIS group showed a trend toward faster recovery and higher postoperative sports activity levels, particularly in the athletic population. Although no statistically significant differences were found between groups overall, these findings suggest potential benefits of avoiding an IF screw in selected patients. Further prospective studies are warranted to better delineate the clinical impact of screw usage in FMTPJA.