An eight-week-old boy presented to the emergency department with active bleeding from a ruptured pseudoaneurysm. Four weeks earlier, he had undergone a percutaneous Achilles tenotomy in an outpatient clinic at an outlying facility in another state following a series of manipulations and Ponseti casts. The initial casting and tenotomy were carried out by a provider listed on the Ponseti International Association web site. The tenotomy appeared to have been performed percutaneously at a single level with a posteromedial approach. The original incision may have healed, but the site of the rupture through the skin was at this incision. Swelling on the medial aspect of the heel was first noted approximately three weeks following the percutaneous tenotomy. An ultrasound of the swelling confirmed the presence of a pseudoaneurysm of the posterior tibial artery that measured 2.62 × 2.54 × 2.71 cm (Fig. 1). Initial treatment included a compression dressing placed by the initial treating provider and outpatient referral to our facility for additional evaluation by a pediatric general surgeon.
En route to our facility for a scheduled clinic appointment, the infant became more irritable and cried excessively. By the time they arrived, the compression dressing was soaked in blood, and there was blood pooling in the car seat. The mother reported that he was pink in color and moving all extremities up to one minute before she entered the emergency room. On presentation, the patient was pulseless, pale, and unresponsive. He was in cardiopulmonary failure with asystole secondary to hemorrhagic shock.
Digital pressure was applied to the posterior tibial artery while cardiopulmonary resuscitation (CPR) was begun. The patient was intubated, and intraosseous access was obtained for initial fluids. Next, central access was obtained. He received additional fluids along with more than 650 cc of packed red blood cells. CPR was accomplished successfully over a twenty-minute interval. He regained spontaneous respirations; however, he was noted to have an upward gaze and some movements representing possible seizure activity. When the patient’s cardiovascular status was stable, he was transported to the operating room.
A combined team of pediatric general and orthopaedic surgeons explored the posterior tibial artery and ligated it proximal and distal to the pseudoaneurysm. The neurovascular sheath and the tibial nerve were identified. During exploration, it appeared that the pseudoaneurysm had ruptured into the area of the previous surgical incision, resulting in exsanguination. Multiple arterial branches were ligated near the pseudoaneurysm. The patient had adequate vascular supply to the foot with a palpable dorsalis pedis pulse, and the foot was pink. He was admitted for observation to evaluate for any secondary central nervous system injury.
The patient did well postoperatively. He was weaned from vasopressors and antiseizure medication and was extubated successfully. Repeat magnetic resonance imaging (MRI) of the brain during hospitalization and at three months following discharge showed no residual abnormalities. There were no symptoms of developmental delay or regression. The original treating surgeon performed the follow-up care of the Ponseti treatment. The patient also had congenital clubfoot on the contralateral side that had been treated without complication from the tenotomy procedure. By report, both feet were functioning well and were symmetrically corrected without evidence of recurrence. When contacted, the family indicated that the child had maintained the correction and was still using a brace at eighteen months postoperatively. Verbal and other neurologic development remained unaffected.
Idiopathic clubfoot deformity is the most common musculoskeletal congenital defect; it occurs in up to 6.8 of every 1000 live births and is bilateral in 40% to 50% of these cases4,5. The Ponseti method is a well-recognized and frequently utilized nonoperative corrective treatment for clubfoot deformity. Roughly 85% of patients undergo percutaneous Achilles tenotomy to correct the equinus deformity after casting has corrected the other foot deformities associated with clubfoot1.
While minor variations in technique occur and are surgeon-dependent, the basic procedure for percutaneous Achilles tenotomy is well recognized and accepted. A vascular examination of the foot is performed prior to the procedure, with palpation of the dorsalis pedis and posterior tibial arterial pulses. The reported rate of deficiency in the dorsalis pedis artery in children with clubfoot deformity is 45%, compared with 8% in controls6. Dobbs et al. described performing Doppler ultrasound examination of the vascular structures if neither pulse is palpable in order to delineate the vascular anatomy prior to the tenotomy procedure2. Pseudoaneurysm as a complication is exceedingly rare; to the best of our knowledge, it is reported only in small series of patients and in few case reports2. Mardjetko et al. reported a rate of 0.15% (four of 2756) for pseudoaneurysm in pediatric patients undergoing all types of foot surgery7.
It is imperative to have a good understanding of the neurovascular anatomy in the immediate vicinity of the Achilles tendon prior to performing a tenotomy. The peroneal artery lies anterolateral to the Achilles tendon8. This is the structure that has been previously described to be involved in vascular injuries following the tenotomy procedure2. Anterolateral to the peroneal artery are the sural nerve and the lesser saphenous vein8. The posterior tibial neurovascular bundle is located anteromedially to the Achilles tendon8,9. One anatomic imaging study, examining the adult ankle, determined that the tibial nerve is located 11.8 ± 2.4 mm and the posterior tibial artery is located 16.7 ± 3.8 mm deep to the Achilles tendon at the level of the tibiotalar joint9. Although, to our knowledge, these distances in infants have not been specified or published, they certainly are much less in a pediatric patient, particularly in an infant, as demonstrated by the close proximity of the Achilles tendon to the neurovascular structures that were affected in our patient. Figure 2 depicts the pertinent cross-sectional anatomy of a normal ankle in a very young child. Dorsiflexion of the foot to achieve maximal distance between the neurovascular bundle and the tendon, as well as strict adherence to close approximation of the scalpel to the anterior aspect of the Achilles tendon throughout the procedure is important. Variations on the percutaneous office procedure include similar techniques performed in the operating room under general anesthesia or conscious sedation so that there is less resistance and presumably more control over the limb, as well as open and “mini-open” tendon lengthening or tenotomy, which allow for direct visualization and isolation of the tendon prior to transection.
The Ponseti method for the treatment of congenital clubfoot deformity is well recognized and commonplace. Pseudoaneurysm is a risk associated with percutaneous Achilles tenotomy, a procedure required in the majority of patients treated by this method. This case report highlights the serious and potentially life-threatening consequences that occur if a pseudoaneurysm ruptures. The survival and recovery of our patient were likely possible because of the family’s proximity to the pediatric emergency room and the availability of a specialized care team at the time of rupture. To our knowledge, this is the first case report of its kind. Physicians should be cognizant of potential vascular injury following percutaneous tenotomy. This case brings to light the question of how best to monitor and treat a pseudoaneurysm once it has been identified. Historically, compression dressing with ultrasound surveillance has been suggested, and, to our knowledge, there are no described cases of surgical treatment for pseudoaneurysm. In the future, surgical treatment to address pseudoaneurysm may be warranted, depending on size, location, and presumed arterial integrity.