Re+Line Bunion Correction System for Correction of Hallux Abducto Valgus Deformity

Transcription

1 Re+Line Bunion Correction System for Correction of Hallux Abducto Valgus Deformity Amber M. Shane, DPM, FACFAS 1, Christopher L. Reeves, DPM, FACFAS 1 1. Orlando Foot & Ankle Clinic, Orlando, FL Abstract Background: Hallux abducto valgus (HAV) deformity is a common and disabling condition that can affect patients of all ages. When conservative options fail to treat HAV, surgical intervention is often necessary to correct the patient s deformity. The authors above propose a new system of fixation for distal first metatarsal osteotomy correcting HAV. Methods: Twenty-four patients underwent a distal first metatarsal osteotomy (Austin osteotomy) and fixated with the Re+Line Bunion Correction System by Nextremity Solutions, Inc. Patient records were reviewed retrospectively to determine the time to weight bearing, time to union of osteotomy, correction of Inter-metatarsal angle 1-2 (IM 1-2) and whether patients necessitated removal of hardware secondary to pain or other complications. Results: 24 of 24 osteotomies healed successfully within 8 weeks. The average time to weight bear was 1 week and the average decrease in the IM 1-2 was 3.6 degrees. Complications included removal of hardware, which included an additional surgical procedure (2 patients). Conclusion: Although further investigation is needed including a larger patient population, the Re+Line system provides an efficient and reliable way to fixate the distal first metatarsal osteotomies. Introduction Pain resulting from hallux valgus deformity can have both extrinsic and intrinsic causes. Impingement of the hallux on the second toe or irritation of the prominent medial eminence in shoe gear are examples of extrinsic causes. Intrinsic pain is caused by abnormal joint mechanics that cause increased joint contact stresses and synovitis and can lead to cartilage degeneration (Sammarco JBJS 2007). Non-operative treatment for HAV should be attempted prior to surgical intervention. Conservative approaches for treatment of HAV include but are not limited to: over the counter orthotics, shoe gear modifications (extra depth shoes with wider toe box) and a silicone spacer in the first web space. When conservative measures fail, surgical intervention is often necessary. There are over 150 surgical procedures that have been described for

2 the treatment of hallux valgus in the orthopedic literature with different modalities for fixation. Of the many osteotomy techniques to fixate hallux abducto valgus, distal head procedures are most commonly used when the IM 1-2 angle is less than 15 degrees (Chandler, Clinics in Pod. Medicine+surg). Austin and Leventen in 1981 published their description of the distal chevron osteotomy with the goal of addressing three key points: restoring the alignment of the first MTP joint, correcting hallux valgus and correcting the metatarsus primus varus while maintaining osteotomy stability to allow early ambulation (Austin DW clinics of Ortho). The authors typically fixate the Austin osteotomy with two screws to comply with AO technique, which creates adequate compression and fixation of the capital fragment after lateral translation. When shifting the capital fragment laterally in a distal first metatarsal osteotomy it is imperative that the surgeon maintains greater than 50% of boney apposition to prevent avascular necrosis (Palmanovich Foot and Ankle clinic 2014). Avascular necrosis (AVN) of the first metatarsal head following the chevron osteotomy has been reported widely in the literature, although encountered very infrequently clinically. In the study by Jones et al, he stated that the true prevalence of AVN is very low with zero cases in a review of eleven clinical studies comprising 2089 patients. The long arm Austin and Reverdin Laird osteotomy can also be performed and fixated with the Re+line system. The reverdin laird modification which was first described in 1977, allows for correction of proximal articular set angle (PASA) and the IM angle in correction of hallux abducto valgus (Hetman J. clinics in pod med and surg 2005). The Re+line system was developed to ensure reproducible success by utilizing tension band plate technology that provides compression across the osteotomy site allowing for increased stability and the potential for early weight bearing. The purpose of this paper is to evaluate the time to weight bear, time to union and correction of the HAV deformity when utilizing the Re+line system. Materials and Methods Twenty-four patients enrolled in the study, who all underwent Austin- Chevron osteotomies and were fixated with the Re+Line system from March 2015 to March The patient population consisted of 24 women and 0 males with an average age of 54 years old. Patient records were reviewed for age at time of surgery, gender, comorbidities, indications for surgery, postoperative course, osteotomy union, time to weight bearing, correction of IM 1-2 angle and any complications associated with the Re+Line system. Radiologic images included the anteroposterior, lateral and medial oblique views of the foot preoperatively, two weeks postoperatively, 8 weeks postoperatively, 12 weeks postoperatively, 6 months postoperatively and as needed if complications arose. Comorbid conditions that were commonly encountered consisted of Diabetes Mellitus and Hypertension.

3 Operative Technique The patient was brought back into the operating room and placed into a supine position. Time out was performed. A well-padded ankle tourniquet was applied to the operative extremity. The foot was cleaned, prepped and draped in the normal aseptic technique. A dorsal medial incision was performed staying medial to the Extensor Hallucis Longus tendon. Incision was carried down through the skin and subcutaneous tissues. All bleeders were ligated as necessary and all neurovascular structures retracted. Dissection was then deepened down to the level of the periosteum of the 1 st metatarsal. Lateral release was then performed to reduce the sesamoids. A capsulotomy was then performed medially at the 1 st MTPJ. The first metatarsal medial eminence was removed, passed to the back table and discarded. Assessment of the metatarsal head and deformity then ensued and the 20mm x 6mm x15mm implant was opened. The landmark-positioning guide was centered on the medial aspect of the metatarsal head utilizing of the apex landmark as a guide. The landmarkpositioning guide was then pinned proximal to the osteotomy cuts. The 1.4mm drill was used to drill the three remaining holes on the landmark-positioning guide. The pin used to stabilize the landmark-positioning guide was removed. The Austin chevron osteotomy then performed, apex distal and at 60 degrees. The capital fragment translated laterally and temporarily fixated with a.045 k wire. The medial prominence was resected from the metatarsal. The Re+Line bunion correction plate was applied while maintaining pressure on the head of the metatarsal at the osteotomy site on the metatarsal shaft. Intraoperative fluoroscopy was used at this time to evaluate for satisfactory reduction of HAV deformity. The longer 2mm drill was then used to drill the proximal screw slot utilizing eccentric drilling technique, appropriate size screw was chosen and inserted noting compression at the osteotomy site. The longest 2mm drill was then used to drill the second hole in the center and appropriate size screw. A capsulorraphy was then performed to clean up redundant capsular tissue. Periosteum and capsular tissues were then re-approximated with 3-0 vicryl, skin re-approximated with 4-0 nylon in a horizontal mattress technique. Dry sterile dressing was then applied to surgical site. Postoperative Course Immediately following the procedure, the patient was non-weight bearing for the first week. The patient was then allowed to partial weight bear to the heel in a post-operative shoe 1 week after surgery. At the two-week post-operative appointment, the dressing was removed, surgical site inspected, plain radiographs obtained and sutures removed if the incision was well coapted. The patient was instructed to begin passive ROM exercises at the 1 st MTPJ. The patient was then placed back into a post op shoe and allowed to continue to partial weight bear to the heel. At six to eight weeks post operatively, incision

4 was inspected once again, range of motion was assessed at the 1 st MTPJ and repeat plain radiographs obtained. The patient was then placed into a normal tennis shoe. Physical therapy was started if warranted and if the patient elected. Final post-operative visit and plain radiograph evaluation obtained six months post-operatively. Results The authors achieved satisfactory correction utilizing the Re+Line product for fixation on distal first metatarsal osteotomies. All twenty-four patients healed successfully. The authors did not have any patients with superficial wound infections. Two out of the twenty-four patients required an additional procedure to remove the hardware, secondary to pain. The removal of hardware was performed only after signs of radiographic union of the osteotomy were present.

5 Discussion Hallux abducto valgus can be a debilitating condition for the active patient and can pose a challenge to the surgeon. There are many surgical options to choose from once conservative measures fail that routinely lead to successful treatment. Surgery does not come without risks, avascular necrosis of the first metatarsal head can result if the surgeon does not know the vascular anatomy of the first metatarsophalangeal joint (Rothwell et al.). AVN was not reported in any of the twenty-four patients who underwent distal first metatarsal osteotomies and fixated with the Re+Line system. The patients who underwent surgery and fixation with the Re+Line system healed uneventfully and saw an average reduction of 3.6 degrees for the IM 1-2 angle. The Re+Line system has proven to be a reliable reproducible way to fixate distal first metatarsal osteotomies in our small retrospective study. Further investigation should be performed to evaluate the Re+Line system including: a larger and balanced patient population, longer follow up period and assessment of patient progress/satisfaction utilizing AOFAS Scores. 1) Palmanovich, E; Myerson MS: Correction of moderate and severe hallux valgus deformity with a distal metatarsal osteotomy using an intramedullary plate. Foot Ankle Clinic. 19(2): , ) Rothwell, M; Pickard, J: The Chevron osteotomy and avascular necrosis. The Foot. 23(1): 34-8, ) Sammarco, VJ: Surgical correction of moderate and severe hallux valgus: proximal metatarsal osteotomy with distal soft-tissue correction and arthrodesis of the metatarsophalangeal joint. Instructional Course Lecture. 57: , ) Jones, KJ; Feiwell, LA; Freedman, EL; Cracchiolo A 3 rd : The effect of chevron osteotomy with lateral capsular release on the blood supply to the first metatarsal head. Journal of Bone and Joint Surgery. 77(2): , ) Chandler, LM: First metatarsal head osteotomies for the correction of hallux abducto valgus. Clinics in Podiatric Medicine and Surgery. 31(2): , ) Austin, DW; Leventen, EO: A new osteotomy for hallux valgus: a horizontally directed V displacement osteotomy of the metatarsal head for hallux valgus and primus varus. Clinical Orthopaedics and related research. 157: 25-30, ) Hetman, J; Myer, KD: The distal metatarsal osteotomy for the treatment of hallux valgus. Clinics in Podiatric Medicine and Surgery. 22(2): , 2005.