Jeannie Huh

Biomechanical Comparison of Intramedullary Screw Versus Low-Profile Plate Fixation of a Jones Fracture

Background: Intramedullary screw fixation of fifth metatarsal Jones fractures often produces satisfactory results, however, nonunion and refracture rates are not negligible. The low-profile “hook” plate is an alternative fixation method that has been promoted to offer improved rotational control at the fracture site, but this remains to be proven. The purpose of this study was to document biomechanical performance differences between this type of plate and a contemporary solid, dual-pitch intramedullary screw in a cadaveric Jones fracture model. Methods: Simulated Jones fractures were created in 8 matched pairs of fresh-frozen cadaveric fifth metatarsals. One bone from each pair was stabilized using an intramedullary TriMed Jones Screw and the other using a TriMed Jones Fracture Plate (TriMed, Inc, Santa Clarita, CA). Controlled bending and torsional loads were applied. Bending stiffness and fracture site angulation, as well as torsional stiffness, peak torque, and fracture site rotation were quantified and compared. Results: Intramedullary screw fixation demonstrated greater bending stiffness and less fracture site angulation than plate fixation during plantar-to-dorsal and lateral-to-medial bending. Torsional stiffness of screw-fixed metatarsals exceeded that of plate-fixed bones at initial loading; however, as rotation progressed, the plate resisted torque better than the screw. No difference in peak torque was demonstrable between fixation methods, but it was reached earlier in specimens fixed with screws and later in those fixed with plates as rotation progressed. Conclusion: In this cadaveric Jones fracture model, intramedullary screw fixation demonstrated bending stiffness and resistance to early torsional loading that was superior to that offered by plate fixation. Clinical Relevance: Although low-profile “hook” plates offer an alternative for fixation of fifth metatarsal Jones fractures, intramedullary screw fixation may provide better resistance to bending and initiation of fracture site rotation. The influence of these mechanical characteristics on fracture healing is unknown, and further clinical investigation is warranted.

Allograft Reconstruction of Chronic Tibialis Anterior Tendon Ruptures

Background: Chronic ruptures of the tibialis anterior tendon are often associated with tendon retraction and poor-quality tissue, resulting in large segmental defects that make end-to-end repair impossible. Interpositional allograft reconstruction has previously been described as an operative option in these cases; however, there are no reports of the clinical outcomes of this technique in the literature. Methods: Eleven patients with chronic tibialis anterior tendon ruptures underwent intercalary allograft recon-struction between 2006 and 2013. Patient demographics, injury presentation, and details of surgery were reviewed. Postoperative outcomes at a mean follow-up of 43.8 (range, 6-105) months included the American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot score, Short Form–12 (SF-12) physical health score, Lower Extremity Functional Score (LEFS), visual analog scale (VAS) pain rating, dorsiflexion strength, gait analysis, and complications. Results: The average postoperative dorsiflexion strength, as categorized by the Medical Council grading scale, was 4.8 ± 0.45. The average postoperative VAS score was 0.8 ± 1.1. The average LEFS was 66.9 ± 17.2, SF-12 physical health score was 40.1 ± 14.4, and AOFAS score was 84.3 ± 7.7. One complication occurred, consisting of transient neuritic pain in the superficial peroneal nerve distribution. There were no postoperative infections, tendon reruptures, reoperations, or allograft-associated complications. Conclusion: Allograft reconstruction of chronic irreparable tibialis anterior tendon ruptures yielded satisfactory strength, pain, and patient-reported functional outcomes. This technique offers a safe and reliable alternative, without the donor site morbidity associated with tendon transfer or autograft harvest. Level of Evidence: Level IV, retrospective case series.

Outcomes of Bone Grafting of Bone Cysts After Total Ankle Arthroplasty

Background: The operative treatment of bone cysts after total ankle replacements (TAR) is not well described. Bone cysts may cause component migration, implant failure, and pain. Surgery is performed on cysts with the goals of reducing pain and preventing component failure. Methods: We retrospectively evaluated a consecutive series of 726 primary TARs performed between January 1998 and May 2013 and identified those who had a subsequent bone cyst grafting procedure. We identified cyst location and method of treatment. Clinical outcomes including secondary procedures, infection rate, complications, and failure rate were recorded. Thirty-one patients were treated with a total of 33 operative procedures for bone cysts after TAR. Of these patients, 22 (71.0%) were males with an average age of 62.2 and median follow-up 65.9 months. Results: Intraoperatively, 22 tibial cysts (71.0%), 20 talar cysts (64.5%), 5 fibular cysts (16.1%), and 13 multiple cysts (41.9%) were treated. Allograft was used in 25 procedures (75.8%), calcium phosphate in 4 (12.1%), cement in 3 (9.1%), and autograft in 1 (3.0%). These procedures were supplemented by calcaneus autograft, allograft mixed with mesenchymal stem cells, platelet-rich plasma, recombinant human bone morphogenic protein-2, and demineralized bone matrix. There were no infections or wound complications. Of the 27 subjects with a successful second surgery, the success rate for bone grafting of cysts was 90.9% (95% CI: 50.8, 98.7%) at 24 months and 60.6% (95% CI: 25.1%, 83.4%) at 48 months. One patient needed a repeat bone grafting. The 4 failures observed postprocedure resulted in 3 tibial and talar component revisions, and 1 tibiotalocalcaneal (TTC) fusion. Conclusions: Grafting bone cysts without revision of TAR was in general an effective and safe means for treating patients with peri-prosthetic bone cysts. Treatment with grafting and supplemental materials may improve implant survivorship and might improve the structural support surrounding the implant. Further exploration of the etiology of bone cysts may aid in the prevention and treatment of cystic formation in the TAR. Level of Evidence: Level IV, case series.

Total Ankle Arthroplasty Following Prior Infection About the Ankle

Background: We evaluated whether a history of prior infection about the native ankle joint, bone, or soft tissues was associated with a higher rate of infection following total ankle arthroplasty (TAA) when compared with that of primary TAA in the general population. Methods: This is a retrospective review of our institution’s TAA registry to identify all patients who reported a prior history of ankle joint sepsis or osteomyelitis and who were subsequently treated with TAA with at least 1-year follow-up. The primary outcome measure was re-infection rate. Secondary outcome measures were patient-reported outcome scores, implant survival, and complications. Twenty-two TAAs were performed in 22 patients, consisting of 9 men and 13 women, with a mean age of 58.4 years (range = 30-80 years). Patients were followed for a mean of 29.3 months (range = 11.4-83.8 months). The length of complete symptom-free interval between the index infection to time of TAA was 8.8 years (range = 0-44 years). These patients had a mean 2.7 (range = 0-13) procedures involving the ipsilateral ankle joint prior to TAA. Results: No deep infection was observed in this series. Eleven patients were followed for more than 2 years, with postoperative visual analog scale scores decreasing from 53.1 (range = 12-90) to 20.6 (range = 0-89) of 100. Ten of the 11 ankles also had AOFAS ankle-hindfoot and SF-36 scores. Their AOFAS ankle-hindfoot score increased from 38.9 (range = 10-61) to 70.1 (range = 29-90), and SF-36 score improved from 40.6 (range = 3.3-76.4) to 67.6 (range = 36.4-85.4). Conclusion: Single-stage TAA can be a viable option to treat arthritic ankle pain for those patients with resolved bone or ankle joint infection, producing improved outcomes in pain and function. Level of Evidence: Level IV, case series.

Characterization and Surgical Management of Achilles Tendon Sleeve Avulsions

Background: An Achilles sleeve avulsion occurs when the tendon ruptures distally from its calcaneal insertion as a continuous “sleeve.” This relatively rare injury pattern may not be appreciated until the time of surgery and can be challenging to treat because, unlike a midsubstance rupture, insufficient tendon remains on the calcaneus to allow for end-to-end repair, and unlike a tuberosity avulsion fracture, any bony element avulsed with the tendon is inadequate for internal fixation. This study aimed to highlight the characteristics of Achilles sleeve avulsions and present the outcomes of operative repair using suture anchor fixation. Methods: A retrospective analysis was conducted on 11 consecutive Achilles tendon sleeve avulsions (10 males, 1 female; mean age 44 years) that underwent operative repair between 2008 and 2014. Patient demographics, injury presentation, and operative details were reviewed. Postoperative outcomes were collected at a mean follow-up of 38.4 (range, 12-83.5) months, including the American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot score, visual analog scale (VAS) for pain, plantarflexion strength, patient satisfaction, and complications. Results: Eight patients (72.7%) had preexisting symptoms of insertional Achilles disease. Ten of 11 (90.9%) injuries were sustained during recreational athletic activity. An Achilles sleeve avulsion was recognized preoperatively in 7 of 11 (64%) cases, where lateral ankle radiographs demonstrated a small radiodensity several centimeters proximal to the calcaneal insertion. Intraoperatively, 90.9% of sleeve avulsions had a concomitant Haglund deformity and macroscopic evidence of insertional tendinopathy. All patients healed after suture anchor repair. The average AOFAS score was 92.8 and VAS score was 0.9. Ten patients (90.9%) were completely satisfied. One complication occurred, consisting of delayed wound healing. Conclusions: Achilles tendon sleeve avulsions predominantly occurred in middle-aged men with preexisting insertional disease, while engaged in athletic activity. Suture anchor fixation, combined with addressing concomitant insertional pathology, was a reliable and safe technique for the operative management of Achilles tendon sleeve avulsions. The majority of patients returned to their preinjury levels of work and recreational activity. Level of Evidence: Level IV, retrospective case series.

Radiographic Outcomes Following Lateral Column Lengthening With a Porous Titanium Wedge

Background: Lateral column lengthening (LCL) is commonly utilized in treating stage II posterior tibialis tendon dysfunction. This study aimed to analyze the outcomes of LCL with porous titanium wedges compared to historic controls of iliac crest autograft and allograft. We hypothesized that the use of a porous titanium wedge would have radiographic improvement and union rates similar to those with the use of autograft and allograft in LCL. Methods: Between May 2009 and May 2014, 28 feet in 26 patients were treated with LCL using a porous titanium wedge. Of the 26 patients, 9 were males (34.6%). The average age for males was 43 years (range, 17.9-58.7), 48.7 years (range, 21-72.3) for females. Mean follow-up was 14.6 months. Radiographs were examined for correction of the flatfoot deformity and forefoot abduction. All complications were noted. Results: Radiographically, the patients had a significant deformity correction in the anteroposterior talo-first metatarsal angle, talonavicular coverage angle, lateral talo-first metatarsal angle, and calcaneal pitch. All but 1 patient (96%) had bony incorporation of the porous titanium wedge. The average preoperative visual analog scale pain score was 5; all patients but 3 (12%) had improvements in their pain score, with a mean change of 3.4. Conclusion: LCL with porous titanium had low nonunion rates, improved radiographic correction, and pain relief. Level of Evidence: Level IV, case series.

Use of a Continuous External Tissue Expander in Total Ankle Arthroplasty A Novel Augment to Wound Closure

Despite major improvements in surgical technique and implant designs in total ankle arthroplasty (TAA), wound healing complications are still commonly encountered. Not only do these problems delay postoperative recovery and threaten functional outcomes, they also carry an increased risk of progression to deep wound infection, which can jeopardize ultimate retention of the implant. In an effort to reduce the high frequency of wound-related complications after TAA, we have incorporated the use of continuous external tissue expansion (CETE) to augment our closures of the anterior ankle incision. CETE is an innovative technique that is currently being used to aid in the rapid closure of acute and chronic full thickness soft tissue defects, including fasciotomy wounds, high grade open fractures, and chronic foot ulcers. By exploiting the viscoelastic properties of the skin, this technique not only facilitates wound edge approximation of full thickness defects, it also helps take tension off tenuous incisions, thus allowing them to heal and reducing the chance for wound dehiscence. This is the first description of the use of an external tissue expander for the prevention of wound healing complications in the setting of TAA. Since introducing CETE to the closure of our TAA incisions, we have seen a decrease in the number of postoperative wound complications and time to wound healing. Based on our experience, we believe that the use of CETE for the prophylactic management of tenuous surgical incisions, specifically those used in the anterior approach to the ankle during TAA, is both safe and efficacious. Levels of Evidence: Level V: Technique tip

Sparing the Naviculocuneiform Joint during Medial Column Stabilization for Rigid Flatfoot Deformity

Category: Midfoot/Forefoot Introduction/Purpose: Combined arthrodesis of the talonavicular (TN) and 1st tarsometatarsal (TMT) joints is a treatment option for the patient with both a rigid flatfoot and hallux valgus deformity or 1st TMT joint arthritis. In these cases, the naviculocuneiform (NC) joint is spared, as long as no evidence of joint collapse or instability is present. The purpose of this study was to assess the effect of this medial column stabilization construct on the spared NC joint over time and its ability to improve the radiographic parameters in the flatfoot deformity. Methods: Patients who underwent concomitant TN and 1st TMT joint arthrodesis, while sparing the NC joint, in the setting of a rigid flatfoot deformity, between January 2006 and December 2014, were identified. The medical records, including preoperative and postoperative radiographs were retrospectively reviewed. Outcomes included radiographic correction gained by surgery (AP and lateral talo-first metatarsal angles), union rate, complications, and need for subsequent surgery. Specific radiographic attention was paid to development of subsequent collapse and/or arthritis at the NC joint at the time of final follow-up. Results: 21 consecutive combined TN and 1st TMT joint arthrodeses were performed. Average age at time of surgery was 61 (range, 23-82) years. 17 patients had a mean follow-up of 35 (range, 12-88) months. Union was achieved at both arthrodesis sites in 16/17 patients (94.1%). One patient (5.9%) had a nonunion at the TN joint, requiring revision arthrodesis. The mean lateral talo- first metatarsal angle correction was 24.5 (range, 12-36) degrees. The mean AP talo-first metatarsal angle correction was 11.6 (range, 0-33) degrees. One patient (5.9%) developed NC joint collapse and underwent subsequent arthrodesis at that level. There was radiographic evidence of NC joint arthritis to varying degrees in all cases by the time of final follow-up, however, none were symptomatic to warrant arthrodesis. Conclusion: Simultaneous arthrodesis of the TN and 1st TMT joints, while sparing the NC joint, is a reliable treatment in the carefully selected patient who presents with both a rigid flatfoot and hallux valgus deformity or 1st TMT joint arthritis. Good results in terms of union rate and radiographic correction, as well as a low complication rate were found in this study. Subsequent joint collapse and symptomatic arthritis at the spared NC joint was rare. Longer term follow-up and inclusion of functional outcomes are warranted in future studies on this topic.

Secondary Fusions Following Total Ankle Arthroplasty

Category: Ankle Arthritis Introduction/Purpose: While it is thought that stresses through the subtalar and talonavicular joints will be decreased in total ankle replacement (TAR) relative to ankle fusion, progressive arthritis or deformity of these joints may require a fusion after a successful TAR. However, after ankle replacement, it is unknown how hindfoot biomechanics and blood supply may have been affected. Consequently, subsequent hindfoot joint fusion may be adversely affected. We hypothesize that fusion rates are not significantly affected following a TAR. Methods: We retrospectively identified a consecutive series of 1001 primary TARs performed between January 1998 and December 2014. We identified patients who underwent a secondary triple, subtalar or talonavicular arthrodesis to treat progressive arthritis or pes planus deformity. Clinical outcomes including pain and functional outcome scores, revision procedures, delayed union, nonunion, complications, and failure rates were recorded. We then compared these patients to patients who had a subtalar fusion after an ankle arthrodesis (13). Results: 26 patients required a subtalar (18), talonavicular (3), talonavicular and subtalar (3), or triple arthrodesis (2) with a mean 70.9 months follow-up. The mean time between TAR and secondary fusion was 37.5 months. 92.7% of the patients went successfully fused. Two patients (7.7%) had a delayed union. Two patients had a nonunion who had one revision talonavicular and one revision subtalar fusion. The mean time to radiographic and clinical fusion was 26.5 weeks. Pain and functional outcome scores improved significantly. There were no differences in the rates of subsequent fusions among implant choices. Compared to thirteen patients with prior ipsilateral ankle arthrodeses and subtalar fusions, patients who had TAR had a higher fusion rate (p=0.03), but did not have a longer time to fusion. Conclusion: Hindfoot arthrodesis following a TAR is safe and effective in improving function and pain. Additionally, arthrodesis following a TAR is more successful than a subtalar fusion following an ankle arthrodesis. While the time to healing is relatively long, various hindfoot fusions can be used to treat progressive arthritis and deformity with high fusion rates.

Secondary Procedures in Third Generation Total Ankle Arthroplasties

Category: Ankle Arthritis Introduction/Purpose: As surgeons have become more comfortable with performing more complex total ankle replacements (TAR) with larger amounts of deformity, it is unclear whether or not to address additional pathology at the time of surgery. Currently, we address all foot and ankle pathology at time of the index arthroplasty. It is unclear however, how often and for what reasons secondary surgery is performed after TAR. We hypothesize that there were no differences in the type or rate of secondary surgeries performed. Methods: We identified a consecutive series of 761 primary TARs performed between January 1998 and December 2014. We identified patients who required a secondary surgery to treat foot and ankle pathology following a STAR, INBONE I/II, or Salto- Talaris. We then analyzed if there were differences between the implants in terms of time to secondary surgery or types of procedures performed. Results: 193 patients (25.3%) required a secondary procedure with an average time to a secondary procedure of 24.5 months. The rate of second surgery in both the Salto (25/113, HR=0.64 with 95%CI=0.408-0.996; p=0.048) and STAR (81/333, HR=0.694 with 95%CI=0.507-0.949; p=0.022) is less when compared to the INBONE group (87/315). The STAR had a significantly longer time to secondary procedure (33.8 months) versus a Salto-Talaris (12.8 months) or an INBONE (19.2 months, p=001). The number of secondary procedures (p< .001), polyethylene exchanges (p< .001), cyst grafting (p=.036) were similar in INBONE and STAR, but significantly more than the Salto. The INBONE prosthesis had a significantly higher talar component failure rate (p=.038), but similar rate of subtalar, ankle, and TTC fusion. Conclusion: Knowledge of the rates and types of secondary surgeries is useful information on the natural history of third generation ankle implants. While there are differences in the rate of failure or revisions between implants, no implant has proven superior to one another.