Calcaneocuboid Distraction Arthrodesis With Synthetic Bone Grafts: Preliminary Results of an Innovative Bone Grafting Procedure in 13 Patients

Evaluation optimum ratio of synthetic bone graft material and platelet rich fibrin mixture in a metal 3D printed implant to enhance bone regeneration

BACKGROUND

This study aims to evaluate the optimal ratio of synthetic bone graft (SBG) material and platelet rich fibrin (PRF) mixed in a metal 3D-printed implant to enhance bone regeneration.

METHODS

Specialized titanium hollow implants (5 mm in diameter and 6 mm in height for rabbit; 6 mm in diameter and 5 mm in height for pig) were designed and manufactured using 3D printing technology. The implants were divided into three groups and filled with different bone graft combinations, namely (1) SBG alone; (2) PRF to SBG in 1:1 ratio; (3) PRF to SBG in 2:1 ratio. These three groups were replicated tightly into each bone defect in distal femurs of rabbits (nine implants, n = 3) and femoral shafts of pigs (fifteen implants, n = 5). Animal tissue sections were obtained after euthanasia at the 8th postoperative week. The rabbit specimens were stained with analine blue, while the pig specimens were stained with Masson-Goldner's trichrome stain to perform histologically examination. All titanium hollow implants were well anchored, except in fracture specimens (three in the rabbit and one fracture in the pig).

RESULT

Rabbit specimens under analine blue staining showed that collagen tissue increased by about 20% and 40% in the 1:1 ratio group and the 2:1 ratio group, respectively. Masson-Goldner's trichrome stain results showed that new bone growth increased by 32% in the 1:1 ratio PRF to SBG, while - 8% in the 2:1 ratio group.

CONCLUSION

This study demonstrated that placing a 1:1 ratio combination of PRF and SBG in a stabilized titanium 3D printed implant resulted in an optimal increase in bone growth.

I am Afraid of Lateral Column Lengthening. Should I Be?

Lateral column lengthening has long been used in conjunction with other soft tissue and bony procedures to correct the midforefoot abduction seen in class B progressive collapsing foot deformity. The effectiveness of this osteotomy to restore the physiologic shape of the foot has been used by foot and ankle surgeons around the world to provide functional improvement for patients suffering from this disease. The overall low complication rates, low nonunion rates, and improved radiographic and functional outcomes provided by lateral column lengthening make this a valuable option for the treatment of class B progressive collapsing foot deformity.

Calcaneocuboid distraction arthrodesis for children with symptomatic pes planovalgus: does fixation improve outcomes?

Lateral column lengthening is a common surgical procedure for addressing symptomatic pes planovalgus foot deformity. For more severe cases, the use of a calcaneocuboid distraction arthrodesis (CCDA) can allow for more powerful correction. Previous reports have cited an increased risk of graft collapse with loss of correction when this procedure is performed without supplemental hardware fixation. The purpose of this study was to assess the outcomes of CCDA in children with and without supplemental locking fixation. A retrospective review from 2008 to 2016 of CCDA procedures with and without supplemental fixation was performed. The primary endpoint was graft collapse. Secondary objectives included evaluation of radiographic loss of correction, hardware failure, pain at 1-year follow-up, reoperations, and changes in the foot loading pattern foot per pedobarography. Twenty-nine feet in 24 patients were eligible for review. Supplemental locked fixation was used in 18 feet [hardware (HW)], with the remaining 11 feet managed without fixation [no hardware (NoHW)]. The overall failure rate on the basis of graft collapse and loss of correction was 55% (56% for the HW group, 55% for the NoHW group). Eleven patients (61%) in the HW group experienced hardware failure, with six (33%) of these requiring hardware removal. Fifty-six percent of the HW group and 45% of the NoHW group reported continued pain at 1-year follow-up. One patient from each group underwent revision arthrodesis. Supplemental locked fixation did not provide additional benefit in preventing graft collapse and loss of correction in this cohort. Alternative strategies should be considered to improve the outcomes for this procedure.

Use of autologous bone grafting from the calcaneus and interconnected porous hydroxyapatite ceramic for bone transplantation in rheumatoid foot surgery

Cancellous bone grafts from the calcaneus have been used for the foot and ankle as well as iliac bone graft; however, there is a sparse report for calcaneal bone transplantation in the field of rheumatoid foot surgery. In this study, safety and usefulness of calcaneal bone grafts, and combination with interconnected porous hydroxyapatite ceramic, was evaluated in rheumatoid arthritis foot surgeries. Of six rheumatoid arthritis cases, three (talo-navicular joint fusion) used a calcaneal bone graft alone, and the remaining three cases (subtalar joint and talo-navicular joint fusion) used a combination of calcaneal bone graft and interconnected porous hydroxyapatite ceramic augmented with dense calcium hydroxyapatite for subtalar bony defect (1.5–2.0 cm) after the correction. Pre- and postoperative Japanese Society for Surgery of the Foot rheumatoid arthritis foot ankle scale scores were obtained for the clinical assessment. As radiographic assessment, tibio-calcaneal angle, calcaneal pitch, talo-1st metatarsal angle, and pronated foot index were also evaluated. After starting weight-bearing or walking, there was no pain and skin trouble at the fusion and harvesting sites. All cases achieved bony fusion within 6–10 weeks. Japanese Society for Surgery of the Foot rheumatoid arthritis foot ankle score was improved in all six cases. Furthermore, tibio-calcaneal angle, talo-1st metatarsal angle, and pronated foot index were also improved at latest follow-up in all cases. In conclusion, autologous bone grafting from the calcaneus was safe and convenient even in rheumatoid foot surgeries. For larger bony defects (1.5–2.0 cm), combination use with interconnected porous hydroxyapatite ceramic augmented with dense calcium hydroxyapatite was also useful.