Joint Preservation of the 1st MTP

Category: Midfoot/Forefoot Introduction/Purpose: Focal damage to articular cartilage and the supporting subchondral plate, commonly referred to as an osteochondral defect (OCD), can be a cause of joint pain and subsequent decreased range of motion. There are few studies specifically describing these lesions in the first metatarsophalangeal (MTP) joint, where they are traditionally grouped into hallux rigidus. There exists an opportunity for early detection and intervention with the intent to prevent deterioration and improve patient outcomes. One contemporary treatment concept is to implant particulated juvenile cartilage allograft to restore articular cartilage. The aim of our study was to review the clinical results of patients that had undergone this procedure for first metatarsal head OCDs. Methods: After IRB approval, a retrospective review of a consecutive case series was studied utilizing the records of three foot and ankle surgeons. Inclusion criteria included all adult patients who were a minimum of one year post surgery and consented to participate. Patient demographics and preoperative visual analog scale (VAS) pain level were recorded from a standardized intake sheet. From the operative note, the OCD size and location was recorded, as well as any concomitant procedures. At a minimum follow up of one year, we obtained objective measurements of arthritis grade and subjective considerations of pain and function, including VAS pain level, Foot Function Index (FFI) questionnaire, the American Orthopaedic Foot and Ankle Society (AOFAS) Hallux Metatarsophalangeal-Interphalangeal scale, and an overall patient satisfaction score. Results: Nine patients met inclusion criteria, 4 males and 5 females. The average age was 41 years old (±11.77, range 21-65). The mean preoperative VAS pain score was 57.50 (±18.32, range 30-80). Four OCDs were located centrally on the first metatarsal head. The average OCD size intraoperatively was 30 mm2 (range 16-49). The average time since surgery was 3.26 years (±1.21, range 1.41-5.62). Average first MTP dorsiflexion was 41.78 degrees (±20.70, range 6-70). The average postoperative hallux rigidus classification was grade 2 (range 1-3). The mean VAS pain score improved to 5.22 (±8.44, range 0-20). The average AOFAS score was 88 (±15.91, range 52-100). The average FFI score was 8.04 (±12.60, range 0-30.6). All but one patient were satisfied or very satisfied with their results. Conclusion: At an average of 3.26 years postoperatively, patients had improved pain, did not show significant progression of their first MTP joint degeneration, and were satisfied with their results. Patients reported very little, if any, limitations in their activity level. We believe that articular damage of the first MTP should be viewed in the same way as OCD lesions in larger joints with emphasis on early detection and treatment to avoid the progression to arthritis. Particulated juvenile cartilage allograft is a valuable tool for surgeons to use in treating focal articular defects of the first metatarsal head

Medial Structure Injury During Suture Button Insertion Utilizing “Center-Center” Technique for Syndesmotic Stabilization

Category: Ankle Introduction/Purpose: The “Center-Center” technique for syndesmosis fixation has been described as an improved and reliable technique for proper reduction of the syndesmosis during ankle fracture repair. Concurrently, the use of a flexible suture button is becoming an established means of syndesmotic stabilization. The purpose of this cadaveric study was to assess for medial structure injury during the placement of a suture button utilizing the “Center-Center” technique for ankle syndesmotic repair at 3 insertion intervals. Methods: Simulated open syndesmosis repair was performed on 10 cadaveric specimens. Three intervals were measured at 10 mm, 20 mm, and 30 mm proximal to the level of the distal tibial articular surface along the fibula. Proper longitudinal alignment of the “Center-Center” technique was completed under fluoroscopic guidance and was marked on the medial aspect of the tibia. The 3 intervals were drilled in the appropriate technique trajectory. The suture button was passed through each drill-hole interval. Using a digital caliper, the distance was measured from each suture button aperture with respect to the anterior tibial tendon, posterior tibial tendon, greater saphenous vein and nerve by single observer. Results: The average distance from the suture button to each anatomic structure was -2.61 ± 3.75 mm for the greater saphenous vein, -3.44 ± 6.82 mm for the saphenous nerve, 15.09 ± 4.02 mm for the anterior tibial tendon, and -21.70 ± 4.89 mm for the posterior tibial tendon. Direct impingement of the greater saphenous vein was seen in 11/30 (36.6%) interval measurements. Six of the 11 (54.5%) entrapment intervals occurred at the 10 mm drill hole. Conclusion: The results of the present study suggest the use of the “Center-Center” technique for syndesmotic repair with suture button application does involve risk of injury to the greater saphenous vein and saphenous nerve. These injuries could manifest as persistent lower extremity edema and paresthesias for injury to the saphenous vein and nerve respectively. The “Center-Center” technique with suture button fixation may warrant a minimal medial open dissection, prior to quadricortical drilling, for optimal placement to prevent neurovascular injury

Intramedullary Screw Fixation and Relevant Diameter of the Proximal Phalanges of the Foot

Category: Midfoot/Forefoot Introduction/Purpose: The average intramedullary diameter of the proximal phalanges of the foot has not been well documented in the literature. This dimension has important implications for surgical fixation devices, such as intramedullary screws. By design, intramedullary fixation devices rely on endosteal fit to provide stability. The precise intramedullary diameter is not readily identifiable on plain radiographs. A better understanding of the average diameter of the proximal phalanges of the foot can assist surgeons in surgical planning and appropriate screw diameter selection to provide more satisfactory patient outcomes. Methods: Twenty below-knee cadaveric specimens were dissected to expose each proximal phalanx. A sagittal saw was used to transect the diaphysis at its narrowest portion. The dorsal to plantar and medial to lateral diameters were measured using a digital manometer. Results: The average diameter dorsal to plantar for each digit was 6.25 ± 2.24 mm, 3.61 ± 1.25 mm, 2.94 ± 0.70 mm, 2.72 ± 0.77 mm, and 2.48 ± 0.80 mm, respectively. The average diameter medial to lateral for each digit was 7.83 ± 2.13 mm, 3.08 ± 0.93 mm, 2.47 ± 0.74 mm, 2.33 ± 0.73 mm, and 2.62 ± 0.69 mm, respectively. The overall average diameter for toes one through five was 7.04 ± 1.95 mm, 3.35 ± 1.04 mm, 2.71 ± 0.66 mm, 2.52 ± 0.71 mm, and 2.55 ± 0.63 mm, respectively. Conclusion: Understanding the intramedullary diameters of the proximal phalanges of the foot is a valuable tool when utilizing intramedullary surgical stabilization. The hallux proximal phalanx demonstrated the largest, and most variable, diameter, which could make selection intramedullary fixation difficult. In addition, the hallux proximal phalanx may lend itself better to 2 smaller fixation devices rather than one larger one. The lesser phalanges demonstrated smaller diameters more consistently, which is more amenable to a single smaller (2.5 mm) intramedullary device. This data can provide surgeons with an expected intramedullary diameter during surgical planning

Structures at Risk from an Intermetatarsal Screw for Lapidus Bunionectomy

Category: Midfoot/Forefoot Introduction/Purpose: The Lapidus procedure is a common procedure for the treatment of hallux abducto valgus. Traditional fixation consists of two crossing screws in the sagittal plane. Despite arthrodesis of the first tarsometatarsal joint, recurrence of the hallux abducto valgus deformity remains a concern. A transverse screw spanning the base of the first metatarsal to the base of the second metatarsal has been advocated to provide transverse plane stability. However, the neurovascular bundle is located within the proximity of this screw. The literature is sparse with a standard technique to safely provide appropriate fixation. An anatomic cadaver study was undertaken to assess the risk of injury to the neurovascular bundle. Methods: Ten unmatched cadaveric limbs that had been disarticulated at the knee were used. Under fluoroscopic guidance, the guide wire to a 4.0-mm screw was driven across the base of the first metatarsal and into the second metatarsal. A 4.0-mm screw was inserted, taking care to obtain osseous purchase into the second metatarsal. A longitudinal incision was made and careful dissection was carried to identify the neurovascular bundle and screw. The neurovascular bundle was inspected for trauma and the proximity of the screws was measured using a digital caliper. Results: There were three left-sided and seven right-sided specimens. Five of the specimens were male and five were female. The mean age of the specimens at date of death was 71.4 years. The mean body mass index was 20.5. The mean distance from the 4.0-mm screw to the first metatarsal base 11.24 mm distal to the first tarsometatarsal joint. The deep plantar artery and deep peroneal nerve was free from injury in 10/10 (100%) specimens. However, the screw was measured to be less than 5 mm in three specimens. In these instances, the average distance of the screw distal to the first tarsometatarsal joint was 12.1 mm. Conclusion: The addition of the intermetatarsal screw for Lapidus bunionectomy is widely accepted clinical practice. Descriptions of the operative technique for the placement of hardware into the second metatarsal have not included specific recommendations to avoid potential risk to the neurovascular bundle as it courses between the bases of the first and second metatarsals. According to this cadaveric study, the neurovascular bundle was avoided with placement of the intermetatarsal screw, if placed approximately 11.24 mm distal to the first tarsometatarsal joint. Further study is warranted to evaluate the optimal distance distal to the first tarsometatarsal joint

Anterior Ankle Incision Complications

Category: Ankle Introduction/Purpose: The anterior incision is commonly used for total ankle replacement (TAR), and anterior approach ankle arthrodesis. Historically, the anterior incision has demonstrated a high incidence of complications, specifically with early generation TAR. Modern TAR designs have provided instrumentation and techniques that better respect the vulnerability of the anterior soft tissues, potentially reducing the incidence of anterior incision related complications. To our knowledge, anterior wound healing rates have not been evaluated in the context of modern anterior approach ankle arthrodesis and arthroplasty. The purpose of this study was to evaluate and compare the incisional healing and complications of the anterior approach for ankle arthrodesis and arthroplasty. Methods: This was an IRB-approved retrospective review of wound healing and complications among 304 patients who underwent primary TAR or ankle arthrodesis via the anterior approach between August 1, 2011 and August 31, 2015. Of the 304 patients, 191 (62.8%) underwent TAR and 113 (37.2%) underwent arthrodesis. The surgical approach, intraoperative soft tissue handling, and postoperative protocol for the first 30 days was the same between groups. Demographics, clinical characteristics of the wound healing, and neurovascular status were analyzed using two-sample t-tests or Wilcoxon rank sum tests for continuous variables and chi-square or Fisher’s exact tests for categorical variables. To diminish the effect of selection bias, a subgroup analysis was performed comparing 91 TAR patients matched to an equal number of ankle arthrodesis patients based upon gender, age, diabetes, and smoking status. Results: The mean follow-up was 11.8 (range, 1.4 to 62.2) months. Overall, 19.7% of patients experienced delayed wound healing greater than 30 days, 15.8% required office-based wound care, 12.2% had a wound infection, 15.1% were prescribed antibiotics, 9.5% underwent wound debridement in the office, 4.6% had nerve injury, and 0.7% had a vascular injury. Implant revision or removal occurred in 10.5%, with a bias towards hardware removal in ankle arthrodesis. In the entire group of 304 patients, there was no difference between TAR and arthrodesis in risk of incisional wound challenges or complications nor neurovascular injury. In the subgroup matched for gender, age, diabetes status and smoking history there was no difference in outcomes. Conclusion: In this large cohort of 304 patients undergoing anterior approach to the ankle, postoperative complication rates were constant at all levels of analysis, with no difference seen between anterior ankle arthrodesis or ankle approach total ankle arthroplasty. This suggests that the primary determinates of complications were neither the demographic nor implant factors considered herein. The anterior ankle incision has a documented wound complication risk, regardless of the surgical procedure, and any modifiable risk factors remain elusive