Review Question - QID 218737

Structure D represents the spring ligament (plantar calcaneonavicular ligament) the deficiency of which is responsible for the loss of medial peritalar stability in the setting of posterior tibialis tendon insufficiency (PTTI) and results in subsequent adult-acquired flatfoot deformity, as shown in Figure A.

Originally referred to as posterior tibial tendon dysfunction or insufficiency (PTTI), adult-acquired flatfoot deformity represents a wide spectrum of deformities across four typically cited stages. A stage I flatfoot represents a flatfoot that has been present throughout adulthood but without deformity, with or without the presence of tenosynovitis and/or tendinosis of the posterior tibialis tendon. In stage II, there is progression to deformity with medial arch collapse due to spring ligament degeneration, which causes plantar flexion and medial shifting of the talar head. It is important to recognize this, given that it can (and should) be repaired in addition to bony corrective procedures in symptomatic stage II flatfoot if progression to a rigid hindfoot with subtalar arthritis and/or tibiotalar arthritis (stages III and IV) has not yet occurred.

Brodell et al. review deltoid-spring ligament reconstruction in adult acquired flatfoot deformity (AAFD) with medial peritalar instability. The authors note that anatomic studies have demonstrated that the superficial deltoid ligament blends with the superomedial spring ligament, forming the tibiocalcaneonavicular ligament (TCNL), with some advocating for the addition of allograft TCNL reconstruction to osseous flatfoot correction to augment medial peritalar stability in advanced AAFD with large spring ligament tears. They reviewed 14 cases and concluded that deltoid-spring ligament
(TCNL) reconstruction is a viable surgical option for those with advanced stage AAFD with medial peritalar instability that leads to improved functional and radiographic outcomes.

Deland et al. reviewed the concept of adult-acquired flatfoot deformity (AAFD). The authors note that there is considerable surgeon-to-surgeon
variability in the treatment of AAFD, particularly in stage II disease. They conclude that in stage IIa deformity, surgical treatment with a medial slide osteotomy and tendon transfer has been shown to provide consistently good results, with lateral column lengthening providing more correction but placing the patient at risk of lateral overload, highlighting that care should be taken to avoid overcorrection and excessive stiffness.

Nery et al. reviewed combined spring and deltoid ligament repair in adult-acquired flatfoot deformity. The authors note that the pathology is typically due to a combination of mechanical failure of the osteoligamentous complex that maintains the medial longitudinal arch of the foot and attenuation or complete tear of the posterior tibial tendon. They conclude by presenting a novel technique to reconstruct the failed deltoid and spring ligament during flatfoot correction using internal brace augmentation with FiberTape® to help protect the soft tissue healing. Using the technique in 10 patients, they found no postoperative complications, stiffness, or loss of correction.

Figure A is a clinical photograph demonstrating the classic appearance of acquired flatfoot deformity. Figure B is a lateral radiograph of the foot demonstrating arch collapse with a preserved subtalar joint, indicating likely stage II flatfoot deformity. Figure C is an illustration depicting the plantar insertions of the following ligaments/tendons: (A) peroneus longus tendon, (B)long plantar ligament, (C) short plantar ligament, (D) spring ligament, (E) tibialis anterior tendon.

Incorrect Answers:
Answer A: Structure A is the peroneus longus tendon.
Answer B: Structure B is the long plantar ligament.
Answer C: Structure C is the short plantar ligament.
Answer E: Structure E is the tibialis anterior tendon.