Single-incision lateral approach for triple arthrodesis

Adult-Acquired Flatfoot Deformity: Combined Talonavicular Arthrodesis and Calcaneal Displacement Osteotomy versus Double Arthrodesis

Background: Adult-acquired flatfoot deformity due to posterior tibial tendon dysfunction (PTTD) is one of the most common foot deformities among adults. Hypothesis: Our study aimed to confirm that the combined procedures of calcaneal displacement osteotomy and talonavicular arthrodesis are equivalent to double arthrodesis. Methods: Between 2016 and 2020, 41 patients (13 male and 28 females, mean age of 63 years) were retrospectively enrolled in the comparative study. All deformities were classified into Stages II and III of PTTD, according to Johnson and Strom. All patients underwent isolated bony realignment of the deformity: group A (n = 19) underwent calcaneal displacement osteotomy and talonavicular arthrodesis, and group B (n = 23) underwent double arthrodesis. Measurements from the Foot Function Index-D (FFI-D) and the SF-12 questionnaire were collected, with a comparison of pre- and post-operative radiographs conducted. The mean follow-up period for patients was 3.4 years. Results: The mean FFI-D was 33.9 (group A: 34.5; group B: 33.5), the mean SF-12 physical component summary was 43.13 (group A: 40.9; group B: 44.9), and the mean SF-12 mental component summary was 43.13 (group A: 40.9; group B: 44.9). The clinical data and corrected angles showed no significant intergroup differences. Conclusion: Based on the available data, our study confirmed that the combined procedures of talonavicular arthrodesis and calcaneal shift, with preservation of the subtalar joint, can be considered equivalent to the established double arthrodesis, with no significant differences in terms of clinical and radiological outcomes.

Double hindfoot arthrodesis using a single-incision medial approach in the correction of adult-acquired flatfoot deformity: a case series

BACKGROUND

Hindfoot arthrodesis is used in patients with advanced-stage acquired flatfoot, usually associated with degenerative joint disease. The objective of the present study was to evaluate the clinical and radiographic results of hindfoot arthrodesis using the single-incision medial approach.

METHODS

A case series of 18 consecutive patients undergoing surgical correction between 2015 and 2018 with hindfoot arthrodesis using the medial approach was evaluated. The clinical assessment used the visual analog pain scale, AOFAS hindfoot score, SF-36, and foot function index. Radiographs and personal satisfaction criteria were also analyzed.

RESULTS

All radiographic parameters evaluated showed a significant improvement (p < .05), except the calcaneal pitch. Pain decreased by 5.1 points (p < .001), and the mean final AOFAS score was 72.6. In three feet, a new surgery was required. Two feet developed talar necrosis. None of the cases presented surgical wound dehiscence, and two presented with superficial infection, which was resolved with the use of oral antibiotics.

CONCLUSION

Double arthrodesis (subtalar and talonavicular) to correct adult-acquired valgus flatfoot using a medial approach has a low risk of soft tissue complications and presents satisfactory functional results. Avascular necrosis is a serious complication that was present in 11% of cases.

Triple Arthrodesis for Adult-Acquired Flatfoot Deformity

Originally described as a means to address fixed deformities or uncontrolled movement of the hindfoot observed in paralytic foot deformities, triple arthrodesis has evolved into a powerful procedure for the correction of a variety of foot deformities. Over the past decade, multiple advances have been made with respect to diagnostic imaging, fixation options, bone graft substitutes, and postoperative regimens. While this operation requires experience and skill to execute, when properly performed, it allows for correction of deformity and a plantigrade and ideally pain-free foot for ambulation. The purpose of this review is to highlight advances in the procedure and its application to the rigid planovalgus foot.

Level of Evidence:

Level V, review.

Adult-Acquired Flatfoot Deformity

Adult-acquired flatfoot deformity (AAFD) comprises a wide spectrum of ligament and tendon failure that may result in significant deformity and disability. It is often associated with posterior tibial tendon deficiency (PTTD), which has been linked to multiple demographic factors, medical comorbidities, and genetic processes. AAFD is classified using stages I through IV. Nonoperative treatment modalities should always be attempted first and often provide resolution in stages I and II. Stage II, consisting of a wide range of flexible deformities, is typically treated operatively with a combination of soft tissue procedures and osteotomies. Stage III, which is characterized by a rigid flatfoot, typically warrants triple arthrodesis. Stage IV, where the flatfoot deformity involves the ankle joint, is treated with ankle arthrodesis or ankle arthroplasty with or without deltoid ligament reconstruction along with procedures to restore alignment of the foot. There is limited evidence as to the optimal procedure; thus, the surgical indications and techniques continue to be researched.

Radiographic Results of Nitinol Compression Staples for Hindfoot and Midfoot Arthrodeses

BACKGROUND

The purpose of this study was to determine the radiographic union rate after midfoot and hindfoot arthrodeses using a new generation of nitinol staples, and to compare outcomes between a nitinol staple construct and a nitinol staple and threaded compression screw construct.

METHODS

A retrospective chart review was performed to identify patients who underwent hindfoot or midfoot arthrodesis using a new generation of nitinol compression staples with or without a partially threaded cannulated screw with minimum 3-month radiographic follow-up. The primary outcome variable was radiographic evidence of arthrodesis on radiographs and, when available, computed tomographic scan in patients who underwent midfoot or hindfoot arthrodesis using nitinol staples. Ninety-six patients and 149 joints were eligible for analysis. Median radiographic follow-up was 5.7 months.

RESULTS

Radiographic union was seen in 93.8% (60/64) of patients and 95.1% (98/103) of joints using the nitinol staple construct. Radiographic union was seen in 90.6% (29/32) of patients and 95.7% (44/46) of joints using the nitinol combined staple and screw construct. There was no significant difference in radiographic union rate or revision surgery between the 2 groups. Seven patients developed nonunion, 4 in the nitinol staple construct group and 3 in the staple and screw group.

CONCLUSIONS

New-generation nitinol staples were safe and effective for hindfoot and midfoot arthrodeses, with a high radiographic union rate. The use of a partially threaded screw for additional fixation was not found to either significantly increase or decrease radiographic fusion with nitinol staple fixation.

LEVEL OF EVIDENCE

Level III, comparative cohort study.

Hindfoot Arthrodesis for the Elective and Posttraumatic Foot Deformity

Triple (talonavicular, subtalar, and calcaneocuboid) joint arthrodesis and most recently double (talonavicular and subtalar) joint arthrodesis have been well proposed in the literature for surgical repair of the elective, posttraumatic, and/or neuropathic hindfoot deformities. The articulation of the hindfoot with the ankle and midfoot is multiaxial, and arthrodesis of these joints can significantly alter the lower extremity biomechanical manifestations by providing anatomic correction and alignment. This article reviews the indications and preoperative planning for some of the most common procedures to address the hindfoot deformity.

A new method for achieving compression in hindfoot arthrodesis

BACKGROUND

When performing hindfoot arthodeses, one goal of fixation is often to achieve compression across the joint. Traditional lag screws are applied eccentrically, providing compression more on the edge of the fusion. A new technique, using a post in one bone and a lag screw through the post to the other bone, may offer better compression across more of the joint.

METHODS

There are three parts to this study comparing a post-and-screw construct to traditional lag screws. Synthetic bone models, representative of the talonavicular joint, were created and assessed for biomechanical measures of compression. Next, the post-and-screw construct was tested in cadavers, under conditions representing early weight bearing after arthrodesis surgery. Finally, 18 patients who had a talonavicular fusion with a post-and-screw construct with one surgeon were compared to the previous 18 patients fixed with traditional screws.

RESULTS

In the synthetic bone model, the post-and-screw construct brought the centre of compression closer to the centre of the joint, suggesting compression was less eccentric. Neither traditional screws nor the post-and-screw construct were sufficiently strong to resist early weight bearing forces in cadaver specimens. In the clinical comparison, four patients had a painful nonunion when fixed with traditional screws, compared to none in the post-and-screw construct.

CONCLUSIONS

A post-and-screw construct spreads the forces of compression more uniformly across an arthrodesis, even when placed eccentrically. Although not all the biomechanical measures were superior, the post-and-screw construct achieved higher levels of successful fusion in patients. This technology may offer improved outcomes in some clinical scenarios and deserves further study.

LEVEL OF EVIDENCE

Level 3.