Background: The triple arthrodesis was described early by Myerson in 1923 and has been the gold standard surgical procedure for various conditions with the goal to reduce pain, improve deformity and facilitate function. Methods: The procedure consists of fusion of the subtalar joint, talonavicular joint and calcaneocuboid joint [1]. The procedure is traditionally done with internal fixation, however, Marinet al. has shown it to be performed with external fixation [2]. Dr. Marin and the associates have developed an alternative technique to perform a triple arthrodesis using internal and external fixation. This paper describes a step-by-step technique to perform a triple arthrodesis with both internal and external fixation. It will demonstrate the use of the prefabricated arches on the footplate for more precise and accurate placement of transosseous wires using arch-wire technique [3]. Results/Conclusion: We believe this technique will not only help increase the ability to achieve fusion with a less chance of non-union, but may also decrease healing time, which may allow patients to be mobile from the first week post-operatively and may diminish the risks associated with being non-weightbearing.
Background: The triple arthrodesis was described early by Myerson in 1923 and has been the gold standard surgical procedure for various conditions with the goal to reduce pain, improve deformity and facilitate function. Methods: The procedure consists of fusion of the subtalar joint, talonavicular joint and calcaneocuboid joint [
Keywords:Triple Arthrodesis, Podiatric Medicine, Surgery, External Fixation, Internal Fixation, Walking, Technique, Podiatry
With a triple arthrodesis that includes only internal fixation, the standard time for non-weightbearing ranges from 1 to 3 months with a below-knee cast which is then transitioned into a walking boot or cast towards the end of therapy [
The triple arthrodesis technique has evolved over the past century to include Ryerson who described the classic technique consisting of joint resection of the subtalar joint, calcaneocuboid joint and talonavicular joint [
Traditional arthrodesis techniques involved joint resection with or without internal fixation. Kirienko et al. developed an operative technique where external fixation followed joint resection for the triple arthrodesis. Joint compression and subsequent fusion was achieved by introducing wires into the foot and arching the wires onto the external fixator. This arch-wire technique allowed for compression of the joints as the wires of the talus, calcaneus, cuboid and navicular were tensioned and fixated upon the external fixator [
Clinical evaluation includes but is not limited to:
1) Post-traumatic arthritis 2) Posterior tibialis tendon dysfunction (PTTD)
3) Charcot neuroarthropathy 4) Collapsing pes planus 5) Rheumatoid arthritis 6) Degenerative joint disease (DJD) (see
7) Neuromuscular imbalance 8) Biomechanical deformities a) Equinovarus b) Cavovarus c) Pes planus Radiographic evaluation includes:
1) Anterior-posterior talus-first metatarsal angle 2) Talonavicular articular angle 3) Lateral talus-first metatarsal angle 4) Calcaneal inclination angle 5) Talar declination angle
Anequinus component to the patient’s lower extremity deformity requires a tendo Achilles lengthening. If deemed necessary, this procedure is performed prior to the dissection for the triple arthrodesis. Equinus is checked by placing the patient’s subtalar joint in the neutral position and dorsiflexing the ankle with the knee flexed at 30 degrees to eliminate the soleus influence and then with the knee fully extended. If equinus is present with the knee flexed and extended, a tendo Achilles lengthening is performed percutaneously with 3 transverse incisions, one lateral and two medial. The first incision is 2 cm proximal to the insertion at the calcaneus and each incision is performed directly over the tendon and is 1 cm apart. The blade is inserted parallel to the tendon fibers and then turned 90 degrees. The tendon is stretched, thus improving foot dorsiflexion. Incision sites are then re-approximated.
The incision sites of the foot are first marked with a marking pen. The lateral incision is marked 1 cm posterior to the lateral malleolus and then curved around the calcaneocuboid joint dorsally and onto the base of the fourth metatarsal. The medial incision is then marked 1 cm anterior and dorsal to the medial malleolus and extended distally to the talonavicular joint. The lower limb is exsanguinated with use of an Esmarch bandage and a thigh tourniquet is inflated to 350 mmHg. If a tendo Achilles lengthening is needed, it is performed at this time as described above. The procedure can begin either medially or laterally as per surgeon’s preference. With the use of #15 blade, the medial incision is made through the skin (see
dissection to gain access to articular surfaces.
A bone curette is utilized to excise the entire cartilagenous surfaces cartilages from the head of the talus and the proximal articular surface of the navicular with care taken to prevent gouging of the joint. A saline-moistened gauze is then placed over the medial incision site so now attention may be directed to the lateral aspect of the foot. The lateral incision is made through the skin and carried down to subcutaneous tissue with use of either sharp and/or blunt dissection (see
Utilizing a lamina spreader, the subtalar joint is distracted thus exposing all articular facets (see
The foot is then placed into the neutral position and then verified with intraoperative fluoroscopy. Once the calcaneus is properly positioned, a guide wire for the 6.5 mm headed, cannulated, short-thread, cancellous, bone screw is driven under fluoroscopy from the body of the calcaneus through the body of the talus with care taken to encompass the posterior facet of the subtalar joint. The countersink is then applied over the guide wire and cannulated measure is then employed to verify length of screw needed. The screw is placed over the guide wire and inserted across the fusion site. It is checked under fluoroscopy to ensure that all threads are distal to the articular surface. Care is taken to ensure no threads cross into the subtalar joint or into the ankle joint. Next, a 5.0 or 5.5 mm (depending on the size of the bone) headed, cannulated, partially-threaded, cortical bone screw guide wire is placed from the navicular into the talus. The countersink is then applied over the guide wire and cannulated measure is then utilized. The screw is placed over the guide wire and inserted across the fusion site. It is checked under fluoroscopy to ensure that all threads extend beyond the previous articulation site. Next, a 5.0 or
5.5 mm (depending on the size of the bone) headed, cannulated, partially-threaded, cortical bone screw guide wire is placed from the cuboid into the calcaneus. The countersink is then applied over the guide wire and the measure is then utilized to obtain the correct length. The screw is then placed over the guide wire and inserted across the fusion site. It is checked under fluoroscopy to ensure that all threads pass distal to the fusion site. All fixations are checked under fluoroscopy to verify proper positioning over the arthrodesis sites (see
All incision sites are then flushed with copious amounts of normal sterile saline. Layered wound closure is performed to ensure a more secure closure. At this level, it is important to cover all exposed bone and hardware to minimize dehiscence. The thigh tourniquet is then released to ensure vascular status is intact to the lower extremity. The skin is then re-approximated.
The external fixator for a triple arthrodesis is constructed with a footplate, matching plate, proximal ring and 4 columns or threaded rods per block. The author prefers to use carbon fiber rings with Radel columns to allow maximum radiolucency (see
After the incision sites are sutured, the tourniquet is deflated and the vascular status is determined to be intact, the external fixator (MDPO Systems, Sunrise, FL) is applied to the lower extremity and transosseous wires are placed as indicated by Catagni [
The first reference calcaneal wire must be parallel to the footplate and perpendicular to the calcaneus is placed as close to the pre-fabricated arches as possible. The matching plate is positioned proximal to the ankle joint and the footplate is kept proximal to the inferior calcaneal tuberosity 1.5 - 2.0 cm to allow for weightbearing (see
and tightened with a nut and fixation bolt and then tensioned on the opposite side to 110 - 130 kg (the wire should be parallel to the reference calcaneal wire). At this point, the frame can now be shifted from medial to lateral to ensure the leg is centered within the frame. Intra-operative fluoroscopy may be used to confirm the proper orientation of the rings and wires to the limb. The remaining wires are placed per author’s preference, but it should be known that the wires can be placed per the surgeon’s choice in no particular order as long as all wires driven are kept within the safe zones and follow standard technique.
The second frontal plane wire placed is a smooth or olive wire at the level of the matching plate oriented slightly anterior-superior to posterior-superior to the arch column (see
The talar wire is positioned in order to compress the subtalar joint (see
The midtarsal wire is then placed to compress the talonavicular and calcaneocuboid joints. The wire is directed along the medial navicular tuberosity towards the lateral cuboid. The anatomical arches will guide wire placement as they mimic the natural arch of the midfoot (see
The second calcaneal wire is then placed from proximal-lateral to distal-medial with the posterior calcaneal tubercle being the reference point. The wire is tightened and tensioned as previously discussed at 70 - 90 kg. Lastly, the midfoot (metatarsal) wire is inserted from medial to lateral and placed distal to the bent compression wire. The wire is secured to the footplate with a fixation bolt and nut and then tensioned on the opposite side at 50 kg. This wire should encompass at least 3 metatarsal shafts (see
Triple arthrodesis with internal and external fixation may provide a decrease in healing time and may decrease complications associated with non-weightbearing as the patient ambulates during the post-operative course. The application of an external fixator manufactured with prefabricated arches along with the resulting weightbearing
forces due to patient mobility allows compression at the subtalar joint, calcaneocuboid joint and talonavicular joint. The technique of using external fixation along with internal fixation is a novel modification to the published triple arthrodesis procedures.