Key Insights On Performing A Revisional Positional First MPJ Arthrodesis

These authors provide a guide for performing a revisional positional first metatarsophalangeal joint (MTP) arthrodesis with autogenous tricortical cancellous bone graft for a malunion in a 54-year-old patient. When performing an arthrodesis of the first metatarsophalangeal joint (MTP), the position of the fusion is of paramount importance for a successful outcome. Often, the desire for complete bone-on-bone contact between two surfaces being prepared for arthrodesis requires the surgeon to spend increased tourniquet time fashioning the “perfect” bone apposition while attempting to maintain optimum correction of deformity. Herein, we describe a technique in which surgeons can achieve optimal position of the bone segments and primary direct bone-on-bone contact where possible, and provide subsequent backfilling with an autograft.    With advances in internal fixation constructs, we are able to confidently neutralize forces across relatively large gaps, backfilling them with autogenous bone graft. Autograft backfilled bone provides the benefit of acting as an osteoconductive scaffold as well as an osteogenic biomaterial, allowing rapid consolidation of the fusion site.¹ Backfilling of bone voids is not a new concept. Surgeons routinely backfill bone graft donor sites with low percentages of complications.^2-4

A Guide To The Case Presentation

A 54-year-old female presented with a painful second digit and great toe. This patient had three previous surgeries for hallux limitus/rigidus. The first surgery was a cheilectomy. Unfortunately, this procedure did not relieve the symptoms. The second surgery consisted of an attempted arthrodesis of the first MTP with screw fixation. Regrettably, the surgery failed and went on to a nonunion. The third surgery was a revision arthrodesis of the non-union of the first MTP using a locking plate.    Approximately 18 months after the third surgery (revision surgery), the patient presented for a second opinion of a previous arthrodesis of her right first MTP. The previous arthrodesis consolidated adequately but the previous surgery left the arthrodesis in a dorsiflexed, abducted position. This caused pressure from the overlapping great toe on the second toe as well as pain from the toe box of shoes, causing pressure to the elevated great toe.    We decided to perform a revisional positional arthrodesis of the first MTP using autogenous bone graft. After ensuring supine positioning of the patient on the operating room table, we applied an ipsilateral thigh tourniquet to the right mid-thigh. Making the incision over the previous incisions of the first MTP, we carried dissection down to bone and created full thickness flaps. Reflecting the flaps medially and laterally exposed the mal-union. Utilizing fluoroscopic guidance, we identified the previous arthrodesis site and used a power saw to create an osteotomy of the near cortex. We took down the remainder of the malunion site with an osteotome and mallet. Inserting a laminar spreader brought the great toe out to length and an anatomic position. We spent a significant amount of time preparing the recipient site for grafting. A 2.0 drill, pics and curettes created bleeding bone.    We proceeded to focus on the lateral wall of the calcaneus where we made an oblique incision posteriorly and inferiorly to the sural nerve as well as the peroneal tendons. We carried this incision down to the periosteum and reflected the tissues, exposing that lateral wall of the calcaneus.    Subsequently, we shifted our attention to ensuring appropriate anatomic positioning of the first MTP. We measured for the needed graft size and used four 0.062 K–wires to create an appropriately sized harvest site in the calcaneus. Employing a power saw, osteotomes and a mallet, we harvested a tricortical cancellous bone graft from the lateral mid-portion of the calcaneus. Then we backfilled the host site with allogenic bone graft.    We fashioned the graft to fit the recipient site and tamped it into place. Subsequently, we inserted a 3.5 mm fully threaded positional screw from the first metatarsal (just behind the condyle) through the graft and into the distal lateral aspect of the great toe, ensuring that the screw would catch the far cortex. Then we inserted a six-hole plate consisting of locking and non-locking screws into the dorsal aspect of the first metatarsal, the autogenous bone graft and the great toe.    Clinical and fluoroscopic examination confirmed the desired anatomic alignment. We subsequently fixated the construct with a combination of locking and non-locking screws. Postoperatively, the patient bore partial weight in a fracture boot. There was good consolidation postoperatively and we were able to achieve a successful arthrodesis with the first MTP in good anatomic alignment.

Final Notes

The positioning of a first MTP arthrodesis is the most important step in this procedure. Most surgeons agree that the hallux should be parallel with the second digit, barring any digital deformity, and rest just off the weightbearing surface with the toenail facing superior in neutral. Depending on the patient’s anatomy, this position can be challenging, especially if it is a revision case. Some surgeons will use cup and cone reamers to fashion ball and socket surfaces. However, there must be no significant additional correction necessary if the surgeon wishes to implement this technique. When one must remove significant bone to achieve the desired position, partial or complete gapping can occur.    Corticocancellous allografts are a historic solution to bridging bony gaps. The properties of these are not optimal for bony fusion across such a cavernous gap. Reasons for allograft failure include resorption of the graft, thermal necrosis from fashioning, lengthy storage times, rejection, trabeculation issues over large areas, the freeze-dried/frozen nature of the graft, and cost.^1,5-10    When it comes to cases like the one above, autogenous bone graft offers the surgeon and the patient the best predictable resolution. The locked plating and axial screw provide the stability needed for primary bone healing. Additionally, this technique allows one to fashion the graft in the desired position with optimal biomechanical accuracy and precision.    The four main principles of positional arthrodesis are as follows: 1. Adequate removal of the subchondral plate/fibrous tissue or bone to bleeding bone 2. Manipulation of bone segments into optimal anatomic functional position 3. Use of fully threaded positional screws and plates 4. Aggressive backfilling of gaps with the needed autogenous graft    Dr. DiDomenico is affiliated with the Heritage Valley Residency Program in Beaver, Pa. He is the Section Chief of Podiatry at St. Elizabeth’s Hospital in Youngstown, Ohio. He is the Director of the Reconstructive Rearfoot and Ankle Surgical Fellowship within the Ankle and Foot Care Centers in Ohio, and the Kent State University College of Podiatric Medicine. Dr. DiDomenico is a Fellow of the American College of Foot and Ankle Surgeons.    Dr. Thomas is a second-year resident at Heritage Valley Hospital in Beaver, Pa. References 1. Faour O, Dimitriou R, Cousins C, Giannoudis PV. The use of bone graft substitutes in large cancellous voids: Any specific needs? Injury. 2011; 42(Suppl 2):S87–S90. 2. Burton DC, Carlson BB, Johnson PL, Manna BJ, Kermani MR, Glattes RC, Jackson RS. Backfilling of iliac crest defects with hydroxyapatite-calcium triphosphate biphasic compound: a prospective, randomized computed tomography and patient-based analysis. Spine J. 2013; 13(1):54–61. 3. Geidman W, Early JS, Brodsky J. Clinical results of harvesting autogenous cancellous graft from the ipsilateral proximal tibia for use in foot and ankle surgery. Foot Ankle Int. 2004; 25(7):451-5. 4. DeOrio JK, Farber DC. Morbidity associated with anterior iliac crest bone grafting in foot and ankle surgery. Foot Ankle Int. 2005; 26(2):147-51. 5. Kwong LM, Jatsy M, Harris WH. High failure rate of bulk femoral head allografts in total hip acetabular reconstructions at 10 years. J Arthroplasty, 1993; 8(4):341-6. 6. Cuttica DJ, Hyer CF. Femoral head allograft for tibiotalocalcaneal fusion using a cup and cone reamer technique. J Foot Ankle Surg. 2011; 50(1):126–129. 7. Den Hartog BD, Palmer DS. Femoral head allograft for large talar defects. Techniques Foot Ankle Surg. 2008; 7(4):264–270. 8. Draenert K, Draenert M, Erler M, Draenert A, Draenert Y. How bone forms in large cancellous defects: Critical analysis based on experimental work and literature. Injury. 2011; 42(Suppl 2):S47–S55. 9. Kucera T, Urban K, Ragkou S. Healing of cavitary bone defects. Eur J Orthop Surg Traumatol. 2012; 22:123–128. 10. Saies AD, Davidson DC. Femoral head allograft bone banking. Aust NZ J Surg. 1990; 60(4):267-270.