This 1999 narrative review covers the full spectrum of posterior tibial tendon insufficiency (PTTI) — the most common cause of acquired adult flatfoot. It defines the four-stage Johnson-Strom-Myerson classification and maps each stage to its operative and nonoperative treatment options. The paper also provides the biomechanical rationale for why tendon transfer alone fails in stage II disease.
When a patient presents with medial ankle pain, a too-many-toes sign, and failed single-leg heel rise, the stage of their PTTI determines the entire surgical plan.
For stage II, resist the urge to do an isolated tendon transfer. FDL alone relieves pain but leaves the deformity uncorrected. The evidence supports combining medializing calcaneal osteotomy with FDL transfer and heel-cord lengthening to address both the dynamic deficit and the structural deformity.
For stage III with fixed deformity, arthrodesis is necessary, but the scope should match the deformity. Subtalar arthrodesis alone may not correct fixed forefoot supination, which then requires talonavicular fusion as well. Triple arthrodesis works but comes with real complication rates and adjacent-joint arthrosis.
One practical pearl: always test gastrocnemius tightness separately from the full Achilles complex (knee extended vs. Flexed). Equinus is commonly driven by the gastrocnemius alone, and missing this means missing a heel-cord lengthening that the reconstruction requires.
This 1999 narrative review covers the full spectrum of posterior tibial tendon insufficiency (PTTI) — the most common cause of acquired adult flatfoot. It defines the four-stage Johnson-Strom-Myerson classification and maps each stage to its operative and nonoperative treatment options. The paper also provides the biomechanical rationale for why tendon transfer alone fails in stage II disease.
When a patient presents with medial ankle pain, a too-many-toes sign, and failed single-leg heel rise, the stage of their PTTI determines the entire surgical plan.
For stage II, resist the urge to do an isolated tendon transfer. FDL alone relieves pain but leaves the deformity uncorrected. The evidence supports combining medializing calcaneal osteotomy with FDL transfer and heel-cord lengthening to address both the dynamic deficit and the structural deformity.
For stage III with fixed deformity, arthrodesis is necessary, but the scope should match the deformity. Subtalar arthrodesis alone may not correct fixed forefoot supination, which then requires talonavicular fusion as well. Triple arthrodesis works but comes with real complication rates and adjacent-joint arthrosis.
One practical pearl: always test gastrocnemius tightness separately from the full Achilles complex (knee extended vs. Flexed). Equinus is commonly driven by the gastrocnemius alone, and missing this means missing a heel-cord lengthening that the reconstruction requires.