Arteriovenous fistula and pseudoaneurysm of the posterior tibial artery after calcaneal slide osteotomy: a case report

Examination of Safe Zone to Avoid Injury of the Lateral Plantar Artery During Calcaneal Osteotomy: A Fresh Cadaveric Study

BACKGROUND

Calcaneal osteotomy are used to treat various pathologies in the correction of hindfoot deformities. But lateral plantar artery (LPA) pseudoaneurysms have been reported following calcaneal osteotomy, and LPA pseudoaneurysms may be at risk for rupture. Although the vascular structures in close proximity to calcaneal osteotomies have variable courses and branching patterns, there is little information on safe zone for LPA during calcaneal osteotomy. The aims of this study were to identify the safety zone to avoid the LPA injury during calcaneal osteotomy.

METHODS

Enhanced computed tomography scans of 25 fresh cadaveric feet (male, n = 13; female, n = 12; mean age 79.0 years at the time of death) were assessed. The specimens were injected with barium via the external iliac artery. Line A is the landmark line and extends from the posterosuperior aspect of the calcaneal tuberosity to the plantar fascia origin, and the perpendicular distance between the LPA and line A at its closest point was measured on sagittal images.

RESULTS

The average perpendicular distance between the LPA and line A at its closest point was 15.2 ± 2.9 mm. In 2 cases (8.0 %), the perpendicular distance between the LPA and line A at its closest point was very close, approximately 9 mm. In 18 of 25 feet (72.0%), the point where perpendicular distance from the line A to LPA is the closest was the bifurcation of one of the medial calcaneal branches from LPA, and in 7 feet in 25 feet (28.0%) feet the point where perpendicular distance from the line A to LPA is the closest was the trifurcation of LPA, medial plantar artery, and one of the medial calcaneal branches.

CONCLUSIONS

Calcaneal osteotomy approximately more than 9 mm from the line A could injure the LPA in overpenetration into the medial aspect of tcalcaneal osteotomy. Completion of the osteotomy on the medial side should be performed with caution to avoid iatrogenic injury of the LPA.

LEVELS OF EVIDENCE:

Level IV, Cadaveric study.

Pseudoaneurysm of the posterior tibial artery after manipulation under anesthesia of a total ankle replacement

Although pseudoaneurysm of the posterior tibial artery has been reported, no investigators have discussed the development of a pseudoaneurysm after manipulation under anesthesia of a total ankle replacement. We present the case of a 59-year-old female with end-stage post-traumatic tibiotalar joint disease who underwent an uneventful INBONE® Total Ankle Replacement. She experienced continued postoperative pain and impingement after physical therapy. Consequently, she underwent manipulation under anesthesia. The manipulation provided complete and immediate pain relief. However, she developed a pseudoaneurysm of the posterior tibial artery that required vascular repair. She recovered uneventfully and was ambulating free of pain with improved functionality. Although manipulation under anesthesia of a total ankle replacement is a valuable, noninvasive tool that can provide near-immediate pain relief, it is important to realize that this distal arterial injury, although uncommon, is a possibility.

Calcaneal osteotomy in the treatment of adult acquired flatfoot deformity

Calcaneal osteotomies are an essential part of our current armamentarium in the treatment of AAFD. Soft tissue correction or bony realignment alone have failed to adequately correct the deformity; therefore, both procedures are used simultaneously to achieve long-term correction. Medial displacement and lateral column lengthening osteotomies in isolation or in combination and the Malerba osteotomy have been employed along with soft tissue balancing to good effect by various authors. The goal is to create a stable bony configuration with adequate soft tissue balance to maintain dynamic equilibrium in the hindfoot. In “pronatory syndromes,” the relation of the osteotomy to the posterior subtalar facet modifies the biomechanics of the hindfoot in different ways. Anterior calcaneal osteotomies correct deformities in the transverse plane (forefoot abduction), whereas posterior tuberosity osteotomies result in “varization” of the calcaneus and correct the frontal plane deformity. The choice of osteotomy depends on the plane of the dominant deformity. If the subtalar axis is more horizontal than normal, transverse plane movement is cancelled out and the frontal plane eversion–inversion is predominant. The patient presents with marked hindfoot valgus without significant forefoot abduction. Conversely, if the subtalar axis is more vertical than normal, transverse plane movement is predominant and the patient presents with forefoot abduction and instability of the medial midtarsal joints, although without significant hindfoot valgus. In this situation, a lateral column lengthening procedure is recommended to decrease the uncovering of the talar head and improve the height of the arch while correcting the forefoot abduction. With a predominant frontal plane deformity, medialization of the calcaneal tuberosity is used to displace the calcaneal weight bearing axis medially, aligning it with the tibial axis and restoring the function of the gastrosoleus as a heel invertor. An essential prerequisite for this is the absence of arthritis affecting the subtalar joint. The Achilles tendon may need to be lengthened at the same time.

Relationship of the Scarf valgus-inducing osteotomy of the calcaneus to the medial neurovascular structures

BACKGROUND

The Scarf valgus inducing osteotomy of the calcaneus is an operative technique to correct varus deformity of the hindfoot. It is versatile with significant corrective power; however, the neurovascular structures are in close proximity on the medial side and thus may be harmed during the osteotomy. Moreover, because this type of osteotomy can cause a great lateral translation, traction of the medial neurovascular structures is possible. We performed an anatomic study to evaluate the medial soft tissues after a lateralizing Scarf-type calcaneal osteotomy.

MATERIALS AND METHODS

The osteotomies were carried out on ten fresh-frozen cadaver specimens. We performed the osteotomy and induced valgus. Then we performed a medial dissection to identify the important medial structures: the medial and lateral plantar nerve (MPN , LPN) and the posterior tibial artery (PTA). We noted their relation to the osteotomy and their integrity.

RESULTS

In several cases, one or more of the structures were sectioned. In five cases, all the structures crossed the osteotomy, four of which even a transection of one or both of the plantar nerves occurred. Although the PTA crossed the osteotomy in eight specimens, there was no transection of this structure.

CONCLUSION

Scarf osteotomy of the calcaneus is a highly corrective osteotomy. However, caution must be exercised when performing as the medial neurovascular structures cross the osteotomy lines and transection can occur.

CLINICAL RELEVANCE

When performing the osteotomy one should keep in mind that vigorous sawing and large displacement can cause damage to the medial neurovascular structures.