A Guide To The Triple Arthrodesis For Hindfoot Deformities
Joint preparation can occur several different ways, including resection of the joints with a saw or osteotome. In cases of severe deformity, one must resect wedges of bone to reduce the deformity adequately. Lambrinudi first described this in 1927 as reported by Bernau.9 Surgeons have continued to use this technique today with excellent success. Alternatively, one can use a rotary burr.
We recommend preparing the joint surfaces with curettage to avoid thermal necrosis of the fusion surfaces followed by fish scaling and fenestration with a 1.5 mm or 2.0 mm drill.
Fixation is largely surgeon dependent with no statistically significant difference between modern fixation techniques, which include screws, staples and plates.10 One can use external fixation in combination with internal fixation or alone. Indications for external fixation for triple arthrodesis include patients with poor bone stock, such as those with Charcot deformity or infection. In 2004, Treadwell showed promising results using an external fixation system in eight patients to allow earlier axial weightbearing.11
A study by Talarico looked at 87 patients undergoing triple arthrodesis with external ring and arched wire compression as the method of fixation.12 All patients were partially weightbearing within the first week postoperatively and 97 percent achieved clinical and radiographic fusion in six to eight weeks. Three of these patients experienced an asymptomatic nonunion and patients in both studies had issues with pin tract drainage and infection. Even with these complications, these studies indicate that with correct patient selection, external fixation does provide a good additional option for fixation.11,12
Keys To Emphasizing Proper Patient Selection
Before pursuing surgical intervention, the physician should pursue a thorough diagnostic workup and exhaust appropriate conservative treatment options. Be advised that in certain instances, clinical and radiographic findings may not correlate. If there is radiographic evidence of multiple joint arthritis but a clinical exam does not match the radiographic findings, one may use joint injections with local anesthesia to identify which joints are the source of pain.
As with any elective surgery, consider the general health of the patient preoperatively. Contraindications to this procedure are the same as for any other major arthrodesis procedure. Factors to consider when delaying surgery include poor nutrition status, endocrine abnormalities, inadequate peripheral flow and active smoking status. The ability to remain non-weightbearing for a significant period of time is also a primary concern in patient selection for this procedure.
A Guide To Post-Op Care And Possible Complications
Postoperatively, patients should expect to be completely non-weightbearing for at least six weeks. Apply a posterior splint until there are signs of incision skin healing. Then transition the patient to a cast or removable controlled ankle motion (CAM) boot for 12 weeks. If clinical and radiographic signs of healing are present, progressive weightbearing can begin at week seven as tolerated. Physical therapy can start at week 12. Patients undergoing triple or ankle fusion should avoid high impact sports and torsional loading in order to reduce the risk of accelerated secondary arthrosis in surrounding joints, arthrodesis failure or stress fracture.13
Like any reconstructive surgery, there are a number of complications that can occur following a triple arthrodesis. These include but are not limited to: wound dehiscence, infection, sural neuralgia, prominent hardware, persistent pain and arthritis of the adjacent proximal and distal joint.