Management of dropped head syndrome: a systematic review and single-arm meta-analysis

Dropped Head Syndrome (DHS) is a rare condition marked by severe neck extensor muscle weakness, leading to a chin-on-chest deformity caused by pathological kyphosis. This study aims to evaluate the efficacy of conservative versus surgical treatments for DHS. A systematic search of PubMed, Embase, and ScienceDirect was conducted for studies on DHS treatments. Outcomes included total/partial improvement, success, and failure rates. Statistical analyses were performed using R software and the "meta" package. We identified 1,252 articles, with 19 studies and 472 patients included. Of these, 134 (28.4%) underwent surgery and 338 (71.6%) received conservative treatment. Partial improvement after conservative treatment was 59% (95% CI 32.76-83.03%; I² = 78%), with total improvement at 4.45% (95% CI 0.01-13.21%; I² = 84%). Success rates were 6.73% (95% CI 0.74-16.16%; I² = 82%), and failure was 100% (95% CI 99.28-100%; I² = 78%). For surgical treatment, total improvement was 100% (95% CI 99.57-100%; I² = 18%), and success was also 100% (95% CI 98.37-100%; I² = 0%), with low heterogeneity. Only two surgical patients failed (95% CI 0.00-1.63%; I² = 0%). Conservative treatment was ineffective in achieving functional recovery and horizontal gaze. Surgical treatment is the preferred option for treating DHS and should be considered a disease-modifying therapy.