Clinical Outcomes of the Lateral Trabecular Metal Total Ankle Replacement at a 5-Year Minimum Follow-up.

BACKGROUND: The Trabecular Metal (Zimmer Biomet, Warsaw, IN) total ankle arthroplasty (TAA) system uses a lateral approach with a fibular osteotomy to gain access to the tibiotalar joint and a sagittally curved tibial component. This is the first TAA system to laterally approach the ankle, and few studies have explored outcomes associated with this implant. This study aimed to report the 5-year clinical and radiographic outcomes as well as the survivorship of the implant. METHODS: Over a 3-year period, 2 fellowship-trained foot and ankle surgeons used this implant system to treat 38 end-stage arthritic ankles. Reoperation and revision data were collected from all patients (100%) as part of the local prospective database. Patients completed the Foot and Ankle Outcome Score (FAOS) questionnaire preoperatively and at each annual follow-up visit; scores for a minimum of 5 years were available for 28 (73.7%) patients. A radiographic analysis compared postoperative coronal and sagittal alignment in weightbearing radiographs at a minimum of 5 years with that at 3 months postoperatively, as well as cyst or lucency formation, which was available for 21 patients (55.3%). RESULTS: At 5 years, there were 3 revisions (7.9%) and 9 reoperations (23.7%). Reoperations included 4 fibular hardware removal and 5 medial gutter debridement procedures. The FAOS significantly improved for all domains (P < .05). Implant positioning did not significantly change between 3 months and 5 years postoperatively. CONCLUSION: Our 5-year results in this small series using this unique prosthesis showed good overall survivorship (92.1%) and a reoperation rate of 23.7%, along with clinically significant improvement in patient-reported outcomes. LEVELS OF EVIDENCE: Level IV: Retrospective case series.

Midterm Survivorship of the INBONE II Total Ankle Arthroplasty.

BACKGROUND: The use of total ankle arthroplasty (TAA) in the treatment of ankle arthritis has grown substantially as advancements are made in design and surgical technique. Among the criteria guiding the choice between arthroplasty and arthrodesis, the long-term survival and postoperative outcomes are of crucial importance. Although outcomes of the INBONE I have been published, there is limited midterm survival data for the INBONE II. The purpose of this study was to determine the radiographic and patient-reported outcomes, and survivorship of this prosthesis in patients with a minimum 5-year follow-up. METHODS: We retrospectively identified 51 ankles (46 patients) from 2010 to 2015 who underwent TAA with the INBONE II prosthesis at our institution. Of these, 44 cases had minimum clinical follow-up of 5 years (mean, 6.4; range 5-9). Median age was 66 years (range 42-81) and median BMI was 27.5 (range 20.1-33.0). A chart review was performed to record the incidence of revision and reoperation. Preoperative and postoperative radiographs were analyzed to assess the coronal tibiotalar alignment (TTA), the talar inclination angle, and the presence of periprosthetic lucencies and cyst formation. Preoperative and minimum 5-year postoperative Foot and Ankle Outcome Score (FAOS) subscales were compared. Survivorship was determined by incidence of revision, defined as removal of a metallic component. RESULTS: The survivorship at 5 years was 98% and the rate of reoperation was 7.8% (n = 4); 2 patients underwent irrigation and debridement for infection, 1 patient underwent a medializing calcaneal osteotomy, and 1 patient underwent open gutter debridement, 1 patient underwent a revision of a subsided talar component at 3.2 years after index surgery. Average postoperative TTA was 88.6 degrees, with 42 rated as neutral (85-95 degrees), 2 varus (<85 degrees), and no valgus (>95 degrees) ankles. At final follow-up, asymptomatic periprosthetic cysts were observed in 8 patients. All FAOS domain scores improved between preoperative and final follow-up. CONCLUSION: At midterm follow-up, we observed significant improvement in radiographic alignment and patient-reported outcome scores for the INBONE II total ankle prosthesis. In addition, this cohort has had a relatively low reoperation rate and high survivorship. LEVEL OF EVIDENCE: Level IV, case series.

Effect of Dexamethasone in Peripheral Nerve Blocks on Recovery of Nerve Function.

BACKGROUND: Peripheral nerve blocks (PNBs) have revolutionized distal extremity surgery reducing pain and improving hospital efficiency. Perineural dexamethasone has been administered with PNBs to prolong their effects, although the safety of dexamethasone has not been established in the literature. This study aimed to determine if the addition of dexamethasone affected the postoperative neurological sensory status for foot and ankle surgeries and the recovery of nerve injuries. We hypothesized that the rate of persistent nerve injury would be higher in the dexamethasone group. METHODS: This is a retrospective observational cohort study of prospectively collected data of all patients from a single foot and ankle surgeon's practice. Perineural dexamethasone was routinely used as an adjunct by the regional anesthesia group until a clinical trend of increased paresthesia was found on short-term follow-up, which led to the discontinuation of its use. In this study, the cohort that received dexamethasone with ropivacaine was compared with the cohort that received ropivacaine alone. The primary outcome was a separate sensory nerve status sheet that was completed for every distal nerve territory for every patient at their follow-up visits at 2 weeks, 6 weeks, 3 months, and 6 months. Univariate analysis and a logistic regression model were used to determine the association between dexamethasone and delayed nerve recovery. A total of 250 patients were included in the study, with 117 patients in the dexamethasone group and 133 in the ropivacaine-only group. RESULTS: The rates of nerve injuries were not different between the groups (72 [62%] in the dexamethasone group vs 79 [59%] in the ropivacaine-only group). However, nerve injury symptoms were more likely to persist and not fully recover in the dexamethasone group (n = 47, 65%) compared with the ropivacaine-only group (n = 32, 41%) (OR, 2.12; P = .006). CONCLUSION: Perineural dexamethasone added to PNBs may be associated with delayed nerve recovery after foot and ankle surgery. It may be prudent to avoid its use until its full safety profile is established in larger prospective trials. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Reoperation Profile of Lateral vs Anterior Approach Ankle Arthroplasty.

BACKGROUND: The operative procedure for a total ankle replacement (TAR) is intimately associated with the prosthetic design. The anterior and lateral approaches both have pros and cons regarding their respective soft tissue complications, osteotomy requirements, orientation of the bone cut, and gutter visualization. Although both have been studied independently, few reports have compared both in the same setting. The purpose of this retrospective study was to investigate the difference in reoperation rate after lateral or anterior approach ankle arthroplasty. We hypothesized that the anterior approach had a higher rate of wound complications. METHODS: We evaluated data from a single center collected between 2014 and 2017, comprising a total of 115 total ankle replacements performed by 1 of 4 fellowship-trained foot and ankle surgeons. Reoperations were recorded as an operative report with classification by Canadian Orthopaedic Foot and Ankle Society (COFAS) Reoperations Coding System (CROCS). The index approach used was determined by the surgeon's practice preference. Patients were included when they had a primary TAR in the time frame noted and had a complete data set up to at least 2 years after surgery. The cohort comprised 67 anterior and 48 lateral operations with balanced demographics for age (95% CI: 63-67 years) and gender (47% F). The lateral group had more complex cases with higher COFAS type arthritis (more periarticular arthritis and surrounding deformity). RESULTS: Comparing the 2 groups, a total of 40 reoperations (7 anterior [A], 33 lateral [L]) occurred in 27 patients (5 A, 22 L). One patient had 4 related reoperations. The only revision was in the anterior group. The only soft tissue reconstruction was a split-thickness skin graft in the lateral group. Nine reoperations were irrigation debridement related to an infection or wound complication (3 A, 6 L). The majority (19/33) of reoperations in the lateral group were gutter debridement (8) or lateral hardware removal (11). Operative time was statistically different at 145 minutes (95% CI: 127-164 minutes) in anterior TAR and 178 minutes (95% CI: 154-202 minutes) for lateral TAR (P = .0058). The odds ratio of having any reoperation with a lateral approach TAR was 6.19 compared to the anterior group. CONCLUSION: The results at the 2-year time point demonstrated that there were more reoperations after a lateral approach TAR than an anterior TAR, recognizing the significant case complexity imbalance between the groups and a corresponding relative increase in resource utilization of lateral TAR patients. The 2 implant designs were associated with different reoperation rates, favoring the anterior group. Change in the lateral fixation may have reduced the risk of repeat surgery. LEVEL OF EVIDENCE: Level III, retrospective comparative series.

Agonizing and Expensive: A Review of Institutional Costs of Ankle Fusion Nonunions.

Nonunion after ankle arthrodesis requiring revision is a challenging operative complication, and bone graft substitutes are costly. This study sought to summarize all institutional expenditures related to the revision of an ankle fusion nonunion, presuming that cost and skin-to-skin time would exceed those of the index surgery. The electronic records from 2 foot and ankle centers were reviewed, leading to a list of patients with 2 or more entries for tibiotalar fusions being generated. A total of 24 cases were found to match the criteria. Demographic factors and skin-to-skin time of the remaining patients were compiled. This cohort included 24 patients (6 female and 18 male) with a mean age of 64 years and body mass index of 30.4 kg/m2. Supplemental clinic visits and investigations were included either after computed tomography to assess union or 365 days after index surgery. Total cost of the revision was calculated from billing codes, length of operation, and period of hospitalization. Postrevision outpatient fees were included as well. The revisions were performed open in all cases, and 21 patients received autograft and/or bone substitute. Mean postoperative hospitalization was 3 days. The additional costs (in US dollars) associated with nonunion were $1061 for imaging, $627 for prerevision visits, $3026 for the revision, $3432 for the hospital stay, and $1754 for postrevision follow-up. The total mean amount was $9683, equivalent to 9 nights of acute inpatient stay. Mean index skin-to-skin time was 114 minutes, being 126 minutes for revisions (P=.26). Additional care related to ankle fusion nonunion represents a financial burden equivalent to 9 nights of acute inpatient stay. The use of an orthobiologic would need to be less than $436 to be cost saving. Revision surgery is not significantly longer intraoperatively than index surgery. [Orthopedics. 2020;43(4):e219-e224.].

Intraoperative Assessment of the Axial Rotational Positioning of a Modern Ankle Arthroplasty Tibial Component Using Preoperative Patient-Specific Instrumentation Guidance.

BACKGROUND: The use of patient-specific instrumentation (PSI) in modern total ankle replacement (TAR) has augmented positioning of the tibial component, eliminating the need for complex jigs. Coronal and sagittal alignment are intuitive with this design and have been studied, but axial rotation has not. The purpose of this study was to assess the relationship between the planned preoperative axial rotation as set by the PSI guide and the rotation determined intraoperatively with non-PSI instrumentation. METHODS: This was a prospective cohort study of 22 consecutive cases. The axial rotation angle between the medial gutter and the tibial implant position on the preoperative CT-scan based plan was extracted. At the time of surgery, the medial gutter alignment instrument from the non-PSI instrumentation was inserted and an intraoperative axial photograph obtained to record the angle between the medial gutter and the axial rotation guide pins set by the PSI instrumentation. The 2 measurements were compared and further statistical analysis included Pearson correlation and paired Student t test. RESULTS: The average axial rotation angle between the medial gutter and the implant on the PSI preoperative plan was 5.4 ± 2.9 degrees, whereas the intraoperative photograph from the medial gutter alignment instrument to the pin was 5.9 ±3.8 degrees. This demonstrated a Pearson correlation of R = 0.54 and a P value of .53. The average difference between the two was -0.46 (95% CI: -2.04, 1.10), meaning that components were either slightly externally rotated or that the fork was aimed internally. Based on this group, 50% (11/22) were within 2 degrees of the target and 77% (17/22) were within 4 degrees of the target. CONCLUSION: Patient-specific guides allowed for reproducible rotational tibial component implantation in modern TAR. Further work is needed to better understand the biomechanical effects of the rotational profile and consequences on survivorship. LEVEL OF EVIDENCE: Level IV, case series.

Prospective Cohort Study on the Employment Status of Working Age Patients After Recovery From Ankle Arthritis Surgery.

BACKGROUND: People who are affected by end-stage ankle arthritis are as disabled as those suffering from arthritis in other main articulations of the lower extremity. Once these patients become unable to perform their job duties, they leave the workforce and require financial aid from government agencies, which represents a considerable economic burden. Regardless of whether arthrodesis or arthroplasty is performed, we hypothesized that patients younger than 55 years at the time of surgery should be able to return to work within 2 years and require less social assistance. METHODS: Patients from 2002 to 2014 included in the nationwide prospective Ankle Reconstruction Database treated for end-stage ankle arthritis with a total ankle replacement or an ankle arthrodesis and younger than 55 years at the time of surgery were included. This study used a standard preoperative survey (AAOS, SF-36) along with the same survey filled by patients in intervals up to 2 years postoperatively. Their employment status was determined at each time point. Participation in third-party wage assistance programs was recorded. This cohort had 194 patients with an average age of 47.0 ± 7.2 years and was balanced in terms of sex (104 female) and side (94 left). RESULTS: The employment rate prior to surgery was 56%, which increased to 62% at the 2-year postoperative mark. With regards to worker's compensation, disability, and social security, 20% of patients left all subsidized programs whereas 4% entered at least 1 which is significant (P < .05). CONCLUSION: The 2-year follow-up after tibiotalar arthrodesis/arthroplasty in patients younger than 55 years showed that significantly more people were able to leave subsidized work assistance programs than enroll in them. LEVEL OF EVIDENCE: Level II, prospective comparative study.