To the best of our knowledge, we described the largest case-control study comparing operative and nonoperative treatment of TCC with RFF (see table 4). We found that operative treatment, consisting in a one-step procedure combining TCC resection, graft interposition and subtalar arthroereisis, may produce better clinical and functional results compared to nonoperative treatment.
Currently, poor evidence supports the management of painful RFF with TCC in children. Recommended treatment includes manipulation, continuous or intermittent casting and orthosis, while surgery is generally reserved to those cases in which nonoperative treatment fails.(1, 13-15, 39)
Concerning the nonoperative treatment, it can relieve pain and improve function in 25%-68% of cases.(18, 40-44) Most authors suggested that surgery should be performed on patients whose symptoms were not relieved by conservative treatment. However, previous reports about nonoperative treatment were often weakened by limited statistical analysis or lack of essential outcome measures. We found that nonoperative management produced satisfactory outcomes (total AOFAS-AHS > 80) in 55% of cases and 7 feet (15%) required surgery after nonoperative treatment. These results are consistent with previous studies investigating the role of nonoperative treatment of RFF with TCC (41, 42). Moreover, in our experience, the manipulation under anesthesia and casting was much more expensive than other nonoperative strategies (for instance, analgesia, physiotherapy and orthotics) since, it contempated an average hospitalization of 4 days and a mean surgical room occupation of 30 minutes. Therefore we believe that this treatment should be reserved only to those cases in which other nonoperative treatments failed, that need but refuse surgery.We believe that efforts should be done to avoid costly and time consuming nonoperative attempts, if they are destined to fail or to be unsatisfactory for the patient. A possible prognostic factor could be the level of pain at baseline as recently suggested by Birisik (14); therefore, children with high level of pain could be addressed directly with surgical treatment.
If surgery is considered as definitive management, the surgeon must keep in mind the goals of surgery: to eliminate pain and improve function.(13, 45)
Currently, there is no complete agreement concerning the best surgical strategy in children with RFF and TCC. Recommended treatments include bar resection alone or combined with tissue interposition and hindfoot correction, (5, 8, 19, 24, 26, 29, 33, 36, 39-41, 46-62) isolated calcaneal osteotomy (13), subtalar fusion or triple arthrodesis; the latter being recommended for subtalar OA, failure of previous surgeries, or large irresectable coalitions with severe heel valgus. (17, 18, 39, 46) The known poor long-term outcomes of triple arthrodesis, however, make this an undesirable option, particularly for children(16).
Concerning the resection of the coalition, several authors reported favorable results in children with isolated TCC resection.
Wilde et al reported results from 17 children (20 feet) undergoing TCC resection and fat interposition. (19) He found that heel valgus >16°, coalition area > 50%, JSN and impingement of the lateral talar process on the calcaneum were predictors of symptoms’ recurrence after surgery. Gantsoudes et al. (29) analyzed a cohort of 32 children (49 feet) treated with TCC resection and fat tissue interposition. They reported satisfactory results in 42 feet (84%), but 11 feet required secondary procedures, in particular 8 corrective osteotomies to realign the hindfoot. The authors aknowledged that a valgus heel could worsen the outcome but they abitually postponed the hindfoot correction, since the use of a cast for eigth weeks could increase the likelyhood of relapse.
Mosca reported outcomes from a cohort of children who underwent isolated calcaneal osteotomy for RFF with TCC, concluding that heel valgus correction may achieve pain relief, whether or not the coalition is resected.(13)
Based on our experience, the heel valgus, whenever present, should be addressed along with the TCC, in order to avoid symptomatic recurrence and need for re-operation.
In our practice, the subtalar arthroereisis is the preferred technique to address the heel valgus in children. Currently, this technique is commonly used to address painful flexible flatfoot in children.(63-66) The main advantages include minimal invasiveness, short surgical time, early return to daily activities, favorable and durable results with low rate of complications. The lateral arthroereisis does not burn any bridges for future treatment modalities, making this procedure suitable for children.(66) Compared to the calcaneal osteotomy (13, 29), the screw arthroereisis limits or does not require a long time of cast immobilization (10, 65, 67, 68). Moreover, there is initial evidence that lateral arthroereisis may offer a potentially less-invasive alternative to lateral column lengthening.(69) On the other hand, potential disadvantages and complications of the subtalar arthroereisis include loosening, breakage of the implant, pain and discomfort at the surgical incision, peroneal spasm, joint effusion, stress fracture and infection (67, 68, 70, 71). Although there is no evidence about the role of the hardware removal, in our practice we routinely remove the calcaneo-stop screw two years after surgery. This procedure maybe reduces the likelihood of breakage or loosening of the screw, residual pain and increase the subtalar motion without significant relapse of the heel valgus deformity.
Some brief reports and short case-series describe the association of TCC resection and hindfoot realignment in children(25, 26, 58, 72, 73).
Giannini et al. investigated 12 children (14 feet) undergoing TCC resection and subtalar arthroereisis by bioresorbable screw, reporting improvement of the subtalar motion in 13/14 patients, complete restoration of alignment in 3 feet, partial in the remaining 11 feet and pain improvement in all cases, at a mean follow-up of 3 years. The authors demonstrated that hindfoot alignment, subtalar motion, and age at surgery were predictors of symptoms’ recurrence after surgery.(25) These findings were confirmed also in other studies, suggesting that, whenever indicated, this kind of surgery should be undertaken at an early age, before the arthritic changes of the subtalar joint might jeopardize the outcomes.(19, 27)
Kernback described excellent results in 3 children with RFF and TCC, undergoing combined TCC resection and calcaneal osteotomy.(26)
To the best of our knowledge, we presented the largest series of RFF with TCC in children, comparing nonoperative and operative management. Nonetheless, this study has weaknesses. The retrospective design and lack of randomization introduced potential biases. In particular, the follow-up period was different between the two groups and insufficient for the potential onset of subtalar OA, especially in the operative group. We performed propensity analysis and statistical adjustment to correct or mitigate biases, nonetheless the concern remains. Few postoperative radiographs were available, therefore, no conclusion could be drawn about radiographic correction, recurrence of coalition, and onset of radiographic OA.
The AOFAS-AHS is a clinician-based outcome measure, which lacks sufficient reliability, validity and numeric threshold for a clinically significant difference.(74)
To overcome this issue, we administered the FADI at the latest visit, but the lack of a preoperative patient-reported measure limits any consideration about the real effectiveness of both treatments from the patient’s perspective. The study compared two possible ways to manage RFF and TCC, thus it cannot completely answer to some important questions such as the role of manipulation over just immobilization, the risk-effectiveness and cost-effectiveness of the anesthesia, the effect of the arthroereisis over just resection and the comparison with other surgical procedures, such as osteotomies. The allograft interposition possibly reduces the rate of relapse and increases subtalar motion but increases the costs of the procedure; therefore, additional studies must be conducted to demonstrate the superiority of the allograft over autograft (fat tissue, tendon sheath), silicone or bone wax.