Inconsistency in the Reporting of Adverse Events in Total Ankle Arthroplasty: A Systematic Review of the Literature

Inconsistency in the Reporting Terminology of Adverse Events and Complications in Hallux Valgus Reconstruction: A Systematic Review

Surgical complications are inevitable in any surgical subspecialty. Throughout the years, many classification systems have been developed to better understand and report such complications. The aim of this systematic review is to investigate the variability and frequency of reporting terms used to describe adverse events and complications in hallux valgus reconstruction. We hypothesized that the terms used would be highly inconsistent, which further promotes a need for a standardized terminology reporting system. Studies related to hallux valgus reconstruction outcomes that met our predetermined inclusion criteria were investigated to identify and report the related adverse terms and complications. Adverse terms and complications were grouped into 9 categories. Of the 142 studies included, 376 distinct terms that described adverse events or complications related to hallux valgus reconstruction were identified. Of these, 73.4% (276/376) were mentioned only once in their respective studies. Five of 376 terms were mentioned in at least 25% of the papers, and only 2 of 376 were mentioned in at least 50%. The most frequently reported adverse events were "Recurrence," mentioned in 77 of 142 studies (54%), followed by "Nonunion," mentioned in 76 of 142 studies (53%). The most reported category was "Bone/Joint" with 135 related terms, mentioned in 135 of 376 of the papers (95.1%). The terminology used in reporting adverse events and complications in surgical hallux valgus correction was highly inconsistent and variable. This represents yet another barrier in accurate reporting of these terms, and subsequently a difficult analysis of the outcomes related to hallux valgus reconstruction. To overcome these challenges, we suggest developing a standardized terminology reporting system.Levels of Evidence: Level III; systematic review of Level III studies and above.

Application of the Mayo Periprosthetic Joint Infection Risk Score for Total Ankle Arthroplasty

BACKGROUND

Assessing patient's risk of infection is fundamental for prevention of periprosthetic joint infection (PJI) after total ankle arthroplasty (TAA). The Mayo Prosthetic Joint Infection Risk Score (Mayo Score) is based on data from total hip and knee arthroplasty and has not been validated for application for TAA.

METHODS

A total of 405 consecutive TAA cases were followed for 6 months for PJI. Individual patients' Mayo Scores were calculated and analyzed with logistic regression and receiver operating characteristic (ROC) for predictability for PJI. A critical cut-off Mayo Score for patients at high risk of PJI was determined by best Youden index. Among the Mayo Score-defined high-risk patients, the contribution of different risk factors were compared between the PJI and non-PJI patients.

RESULTS

There were 10 cases of PJI (2.5%) among the 405 cases within 6 months after TAA. Of the 405 patients, the Mayo Scores ranged between -4 and 13 (median 2; interquartile range 0-5). The average Mayo Score was 2.5 ± 3.4 in the non-PJI patients and 7.7 ± 3.1 in the PJI patients (P < .001). Logistic regression showed that the probability of PJI increased with higher Mayo Scores (odds ratio 1.48, 95% CI 1.23-1.78). All but 1 PJI patients had a Mayo Score >5. The sensitivity and specificity were 90.0% and 84.3%, respectively, when a Mayo Score >5 was used as a criterion for high risk of PJI.

CONCLUSION

This study demonstrated that the Mayo Score could similarly predict PJI risk after TAA as in total hip and knee arthroplasty. Data analysis suggests that a Mayo Score >5 could be a criterion for identifying high-risk patients for PJI, although further validation with a large number of PJI cases is necessary.

LEVEL OF EVIDENCE

II, developing diagnositic criteria with consecutive cases.

Complications after total ankle arthroplasty- A systematic review

BACKGROUND

Total ankle arthroplasty was developed as an alternative option to ankle arthrodesis in patients with end-stage ankle osteoarthritis. Multiple trials have assessed the outcomes of ankle arthroplasty, but complication risk or relative effectiveness is not systematized in literature.

AIM

Review complications of new designs of total ankle arthroplasty and the relationship between their severity and failure rates.

METHODS

We reviewed complications and revision rates of prospective studies of primary total ankle arthroplasty that included more than 50 patients and with minimum 2 years follow-up.

RESULTS

We included 22 studies (4412 ankles, median age of 61.9 years) with an adjusted mean follow-up time of 66.6 ± 40.9 months. The adjusted mean complication rate was 23.7 % (2.4-52 %), mostly high-grade complications (35.6 %). We found a statistically significant positive correlation between high- and medium-grade complications and revision rates.

CONCLUSION

Patient selection is crucial to successfully treat end-stage ankle osteoarthritis. Further multicenter clinical trials with consistent reporting of complications are warranted.

Total Ankle Replacement Versus Arthrodesis for End-Stage Ankle Osteoarthritis: A Randomized Controlled Trial

BACKGROUND

End-stage ankle osteoarthritis causes severe pain and disability. There are no randomized trials comparing the 2 main surgical treatments: total ankle replacement (TAR) and ankle fusion (AF).

OBJECTIVE

To determine which treatment is superior in terms of clinical scores and adverse events.

DESIGN

A multicenter, parallel-group, open-label randomized trial. (ISRCTN registry number: 60672307).

SETTING

17 National Health Service trusts across the United Kingdom.

PATIENTS

Patients with end-stage ankle osteoarthritis, aged 50 to 85 years, and suitable for either procedure.

INTERVENTION

Patients were randomly assigned to TAR or AF surgical treatment.

MEASUREMENTS

The primary outcome was change in Manchester-Oxford Foot Questionnaire walking/standing (MOXFQ-W/S) domain scores between baseline and 52 weeks after surgery. No blinding was possible.

RESULTS

Between 6 March 2015 and 10 January 2019, a total of 303 patients were randomly assigned; mean age was 68 years, and 71% were men. Twenty-one patients withdrew before surgery, and 281 clinical scores were analyzed. At 52 weeks, the mean MOXFQ-W/S scores improved for both groups. The adjusted difference in the change in MOXFQ-W/S scores from baseline was -5.6 (95% CI, -12.5 to 1.4), showing that TAR improved more than AF, but the difference was not considered clinically or statistically significant. The number of adverse events was similar between groups (109 vs. 104), but there were more wound healing issues in the TAR group and more thromboembolic events and nonunion in the AF group. The symptomatic nonunion rate for AF was 7%. A post hoc analysis suggested superiority of fixed-bearing TAR over AF (-11.1 [CI, -19.3 to -2.9]).

LIMITATION

Only 52-week data; pragmatic design creates heterogeneity of implants and surgical techniques.

CONCLUSION

Both TAR and AF improve MOXFQ-W/S and had similar clinical scores and number of harms. Total ankle replacement had greater wound healing complications and nerve injuries, whereas AF had greater thromboembolism and nonunion, with a symptomatic nonunion rate of 7%.

PRIMARY FUNDING SOURCE

National Institute for Health and Care Research Heath Technology Assessment Programme.

Noninvasive Soft Tissue Expansion Strips and Wound Complications After Total Ankle Arthroplasty

BACKGROUND

Total ankle arthroplasty through the anterior approach (TAR-AA) is an increasingly popular treatment for ankle arthritis, but it carries a known risk for wound complications. Several products have been investigated to mitigate this risk; however, most are either costly or invasive. Noninvasive skin expansion strips (NSESs) were designed to transfer tension away from the incision and induce new skin growth at the edges of the strips. We hypothesize that postoperative application of NSESs will decrease unplanned clinic visits and wound complications after TAR-AA.

METHODS

This is a prospective cohort study of 41 patients at a single institution (3 surgeons) treated with NSESs after undergoing TAR-AA. An additional 41 consecutive historical patients treated without NSESs were retrospectively included as a control group. Patients received application of NSESs in the operating room after routine wound closure and again 2 weeks postoperatively. No other changes were made to the surgeons' wound closure technique, immobilization, follow-up timing, or rehabilitation protocols. Primary outcomes included (1) additional clinic visit required for wound assessment or suture removal, (2) superficial wound complication, and (3) deep infection.

RESULTS

Baseline demographics did not differ significantly from our 41 consecutively treated historical controls. Additional clinic visits for suture removal or wound evaluation were significantly lower for patients treated with NSESs (15%, 6 of 41) compared to the control group (49%, 20 of 41) (P = .001). There was also a significant difference in the superficial wound complication rate in the treatment group vs control group, 2% and 12%, respectively (P = .04). There were no deep infections in either group.

CONCLUSION

Noninvasive skin expansion strips placed after TAR-AA with an anterior approach have the potential to decrease wound complications and unplanned clinic visits. Further high-volume or randomized studies are needed to clarify their cost effectiveness and effect on long-term outcomes.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

The Role of Distraction Arthroplasty in Managing Ankle Osteoarthritis

Ankle distraction arthroplasty (DA) is a joint-preserving option for the treatment of ankle osteoarthritis. The ideal patient is a young, active person who is compliant with follow-up and understands that clinical improvements may not be fully evident until 1 year after surgery. The procedure promotes cartilage healing and regeneration by removing mechanical stress at the joint surface through the application of a joint-spanning external fixator. There is an array of adjuvant procedures commonly performed to optimize healing potential-including microfracture, osteophyte removal, osteotomies, and soft tissue balancing procedures. Short- and intermediate-term studies have been promising, though there is a wide variance in reported failure and complication rates.

Revision Rates After Total Ankle Replacement: A Comparison of Clinical Studies and Arthroplasty Registers

BACKGROUND

The aim of this study was to assess the outcome of total ankle replacement (TAR) regarding revision rates by comparing clinical studies of the last decade to data displayed in arthroplasty registers. The secondary aim was to evaluate whether dependent clinical studies show a superior outcome to independent publications. Additionally, revision rates of mobile bearing implants (MB-TARs) were compared to those of fixed bearing implants (FB-TARs).

METHODS

Clinical studies on TARs between 2010 and 2020 were systematically reviewed, with the endpoint being a revision for any reason. The parameter "revision rate per 100 observed component years (CYs)" was calculated for each publication. The pooled revision rate for clinical studies was compared to the data reported in arthroplasty registers. In a second step, revision rates were subdivided and analyzed for independent and dependent publications and for FB-TARs and MB-TARs.

RESULTS

A total of 43 publications met the inclusion criteria comprising 5806 TARs. A revision rate of 1.8 per 100 observed CYs was calculated, corresponding to a 7-year revision rate of 12.6%. The 3 arthroplasty registers included showed revision rates ranging from 8.2% to 12.3% after 7 years. No significant difference between dependent and independent publications nor between FB-TARs and MB-TARs was detected.

CONCLUSION

Revision rates of clinical studies and arthroplasty registers are comparable. Surgeons can compare their own revision rates with those from this study. Dependent studies do not seem to be biased, and no superiority for one bearing type can be described.

LEVEL OF EVIDENCE

Level III, systematic review of level III studies.

Three-Year Rates of Reoperation and Revision Following Mobile Versus Fixed-Bearing Total Ankle Arthroplasty: A Cohort of 302 Patients with 2 Implants of Similar Design

BACKGROUND

Currently, the implants utilized in total ankle arthroplasty (TAA) are divided between mobile-bearing 3-component and fixed-bearing 2-component designs. The literature evaluating the influence of this mobility difference on implant survival is sparse. The purpose of the present study was therefore to compare the short-term survival of 2 implants of similar design from the same manufacturer, surgically implanted by the same surgeons, in fixed-bearing or mobile-bearing versions.

METHODS

All patients were enrolled who underwent TAA with either the mobile-bearing Salto (Tornier and Integra) or the fixed-bearing Salto Talaris (Integra) in 3 centers by 2 surgeons between January 2004 and March 2018. All patients who underwent TAA from January 2004 to April 2013 received the Salto implant, and all patients who underwent TAA after November 2012 received the Salto Talaris implant. The primary outcome was time, within 3 years, to first all-cause reoperation, revision of any metal component, and revision of any component, including the polyethylene insert. Secondary outcomes included the frequency, cause, and type of reoperation.

RESULTS

A total of 302 consecutive patients were included, of whom 171 received the mobile-bearing and 131 received the fixed-bearing implant. The adjusted hazard ratio for all-cause reoperation was 1.42 (95% confidence interval [CI], 0.67 to 3.00; p = 0.36); for component revision, 3.31 (95% CI, 0.93 to 11.79; p = 0.06); and for metal component revision, 2.78 (95% CI, 0.58 to 13.33; p = 0.20). A total of 31 reoperations were performed in the mobile-bearing group compared with 14 in the fixed-bearing group (p = 0.07). More extensive reoperation procedures were performed in the mobile-bearing group.

CONCLUSIONS

With the largest comparison of 2 implants of similar design from the same manufacturer, the present study supports the use of a fixed-bearing design in terms of short-term failure. We found a 3-times higher rate of revision among mobile-bearing implants compared with fixed-bearing implants at 3 years after TAA. Reoperations, including first and subsequent procedures, tended to be less common and the causes and types of reoperations less extensive among fixed-bearing implants.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Assessing risk of damage to posterior ankle structures during total ankle arthroplasty

AIMS

Arthroplasty has become increasingly popular to treat end-stage ankle arthritis. Iatrogenic posterior neurovascular and tendinous injury have been described from saw cuts. However, it is hypothesized that posterior ankle structures could be damaged by inserting tibial guide pins too deeply and be a potential cause of residual hindfoot pain.

METHODS

The preparation steps for ankle arthroplasty were performed using the Infinity total ankle system in five right-sided cadaveric ankles. All tibial guide pins were intentionally inserted past the posterior tibial cortex for assessment. All posterior ankles were subsequently dissected, with the primary endpoint being the presence of direct contact between the structure and pin.

RESULTS

All pin locations confer a risk of damaging posterior ankle structures, with all posterior ankle structures except the flexor hallucis longus tendon being contacted by at least one pin. Centrally-aligned transcortical pins were more likely to contact posteromedial neurovascular structures.

CONCLUSION

These findings support our hypothesis that tibial guide pins pose a considerable risk of contacting and potentially damaging posterior ankle structures during ankle arthroplasty. This study is the first of its kind to assess this risk in the Infinity total ankle system. Cite this article: Bone Jt Open 2021;2(7):503-508.

Outcomes of Ankle Arthrodesis Conversion to Total Ankle Arthroplasty: A Systematic Review

Ankle arthrodesis (AA) provides reliable pain relief, good patient satisfaction scores, and improved overall function. However, this procedure has been associated with numerous complications and sequelae, such as pseudoarthrosis, malunion, gait abnormalities, increased demand on surrounding joints, and a long period of convalescence. Conversion to total ankle arthroplasty (TAA) is a potential option in the management of these complex and challenging situations. The purpose of this study is to investigate the outcomes of AA conversion to TAA. A systematic review of electronic databases was performed. Six studies involving 172 ankles met inclusion criteria. The weighted mean preoperative Visual Analogue Scale (VAS) score at the time of TAA conversion was 7.8 and the weighted mean postoperative VAS score at the time of final follow-up was 2.5. The weighted mean preoperative AOFAS score at the time of TAA conversion was 32 and the weighted mean postoperative AOFAS score at the time of final follow-up was 72.4. The rate of salvage tibiotalocalcaneal arthrodesis was 2.3% and rate of transtibial amputation was also 2.3% after attempted conversion from initial AA to TAA. Conversion of AA to TAA appears to be a viable option to improve patient outcomes and prevent extensive hindfoot arthrodesis and transtibial amputation. More prospective studies with consistent reporting of outcomes, complications, and revision rates with long-term follow-up are needed.

Protective Approach for Anatomical Structures at Risk in Total Ankle Replacement

Currently, total ankle replacement (TAR) is an alternative to arthrodesis in selected patients, with the anterior approach being the most widely used to carry it out. Regardless of the type of implant used, the pins for bone resection guides, chisels, and the saw for distal tibial resection can endanger the neurovascular and tendon structures that lie in intimate proximity to the posterior aspect of the ankle. Additionally, there is a documented complication rate of up to 15.3% in such surgery. We have implemented a protective posteromedial approach that complements the anterior approach to reduce this risk of intraoperative iatrogenic injury. Using this method we introduce a protective instrument that separates the posterior anatomical structures from the posterior cortex of the tibia. This article describes the surgical technique used to carry out TAR through an anterior approach in a safer way, without increasing complications or the duration of real-time surgery.

Total ankle arthroplasty

AIMS

We report the medium-term outcomes of a consecutive series of 118 Zenith total ankle arthroplasties (TAAs) from a single, non-designer centre.

METHODS

Between December 2010 and May 2016, 118 consecutive Zenith prostheses were implanted in 114 patients. Demographic, clinical, and patient-reported outcome measures (PROMs) data were collected. The endpoint of the study was failure of the implant requiring revision of one or all of the components. Kaplan-Meier survival curves were generated with 95% confidence intervals (CIs) and the rate of failure calculated for each year.

RESULTS

Eight patients (ten ankles) died during follow-up, but none required revision. Of the surviving 106 patients (108 ankles: rheumatoid arthritis (RA), n = 15; osteoarthritis (OA), n = 93), 38 were women and 68 were men, with a mean age of 68.2 years (48 to 86) at the time of surgery. Mean follow-up was 5.1 years (2.1 to 9.0). A total of ten implants failed (8.5%), thus requiring revision. The implant survival at seven years, using revision as an endpoint, was 88.2% (95% CI 100% to 72.9%). There was a mean improvement in Manchester-Oxford Foot and Ankle Questionnaire (MOXFQ) from 85.0 to 32.8 and visual analogue scale (VAS) scores from 7.0 to 3.2, and overall satisfaction was 89%. The three commonest complications were malleolar fracture (14.4%, n = 17), wound healing (13.6%, n = 16), and superficial infection (12.7%, n = 15). The commonest reason for revision was aseptic loosening. No patients in our study were revised for deep infection.

CONCLUSION

Our results show that Zenith survival rates are comparable with those in the literature for other implants and in the National Joint Registry (NJR). Overall patient satisfaction was high as were functional outcomes. However, the data highlight potential complications associated with this surgery. The authors believe that these figures support ankle arthroplasty as an option in the treatment of ankle arthritis. Cite this article: Bone Joint J 2021;103-B(4):696-703.

Adverse events related to total ankle replacement devices: an analysis of reports to the United States Food and Drug Administration

Background

The published outcomes of total ankle replacement (TAR) implants came from limited institutions creating observational bias. For broader perspective, we queried the Food and Drug Administration’s (FDA) Manufacturer and User Facility Device Experience (MAUDE) voluntary database to explore complications reported outside published literature.

Methods

The database was reviewed retrospectively between November 2011 and April 2019 using two product codes assigned to six TAR devices.

Results

Among 648 relevant reports available in the database, common complications were aseptic loosening (19.3%), infection (18.2%), and alignment/mechanical issues (16.5%). Others included instrument/instrumentation complications, impingement, polyethylene problems, fractures, avascular necrosis of talus (AVN), and packaging issues.

Conclusion

MAUDE database revealed various patterns of device-related malfunctions that have been under-reported in published data. Despite inconsistency in the available reports, it provided opportunities for improvements in quality control, device design, and ultimately patient safety. Database would be further strengthened by more robust reporting mechanism or mandatory reporting of device-related complications.

Analysis of early failure rate and its risk factor with 2157 total ankle replacements

The failure rate of TAA is still higher than that of other joint replacement procedures. This study aimed to calculate the early failure rate and identify associated patient factors. Data from the Korean Health Insurance Review and Assessment Service database from 2009 to 2017 were collected. We evaluated patients who had TAA as a primary surgical procedure. Early failure was defined as conversion to revision TAA or arthrodesis after primary TAA within five years. Patients with early failure after primary TAA were designated as the "Failure group". Patients without early failure and who were followed up unremarkably for at least five years after primary TAA were designated as the "No failure group". Overall, 2157 TAA participants were included. During the study period, 197 patients developed failure within five years postoperatively, for an overall failure rate of 9.1%. Significant risk factors for early failure were history of chronic pulmonary disease, diabetes, peripheral vascular disease, hyperlipidemia, dementia, and alcohol abuse. A significant increase of odds ratio was found in patients with a history of dementia, chronic pulmonary disease, and diabetes. Surgical indications and preoperative patient counseling should consider these factors.

Utility of Dehydrated Human Amniotic Membrane (DHAM) in Total Ankle Arthroplasty

BACKGROUND

Wound complications after total ankle arthroplasty (TAA) are a common postoperative complication occurring in 14% to 66% of all surgeries. Soft tissue breakdown along the anterior incision can cause exposure of anterior tendons and implant, and adhesions of the extensor tendons of the foot. Recent publications have advocated for the implantation of dehydrated human amniotic membrane (DHAM) allograft during closure of anterior ankle incisions during TAA. The goal of this study was to determine whether implantation of DHAM allograft in TAAs decreased overall postoperative wound complications.

METHODS

One hundred seventy patients with end-stage ankle arthritis refractory to conservative management underwent TAA with a standard anterior approach by 1 of 3 board-certified foot and ankle orthopedic surgeons. Ninety-one patients underwent closure of the anterior incision with addition of DHAM, whereas 79 patients served as the control (no addition of DHAM). The primary endpoints considered were postoperative complications and reoperation. Included in the postoperative complications was return to the operating room, postoperative plastic surgery intervention, wound communication with the implant, removal of the implant, neurolysis, tendon debridement, and extensor hallucis longus contracture/adhesions.

RESULTS

In the analysis of our demographically homogenous cohorts, there was no statistically significant difference in any postoperative complications between patients closed with DHAM and controls. Return to the operating room occurred in 8.9% of controls and 15.4% of the DHAM group (P = .291). Similarly, there was no statistically significant difference in postoperative plastic surgery, wound communication with the implant, implant removal, neurolysis, and tendon debridement between the control and DHAM groups.

CONCLUSION

The application of DHAM theoretically acts to decrease overall wound complications in TAA. The use of DHAM preceding wound closure in TAA did not show a statistically significant reduction in overall wound complications in our retrospective analysis. Further study, including prospective randomized studies, is needed to further investigate the effectiveness of DHAM in reducing wound complications in TAAs.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Variability in the Reporting Terminology of Adverse Events and Complications in Ankle Fracture Fixation: A Systematic Review

BACKGROUND

Classification systems for the reporting of surgical complications have been developed and adapted for many surgical subspecialties. The purpose of this systematic review was to examine the variability and frequency of reporting terms used to describe adverse events and complications in ankle fracture fixation. We hypothesized that the terminology used would be highly variable and inconsistent, corroborating previous results that have suggested a need for standardized reporting terminology in orthopedics.

METHODS

Ankle fracture outcome studies meeting predetermined inclusion and exclusion criteria were selected for analysis by 2 independent observers. Terms used to define adverse events and complications were identified and recorded. Discrepancies were resolved by consensus with the aid of a third observer. All terms were then compiled and assessed for variability and frequency of use throughout the studies involved. Reporting terminology was subsequently grouped into 10 categories.

RESULTS

In the 48 studies analyzed, 301 distinct terms were utilized to describe complications or adverse events. Of these terms, 74.4% (224/301) were found in a single study each. Only 1 term, "infection," was present in 50% of studies, and only 19 of 301 terms (6.3%) were used in at least 10% of papers. The category that was most frequently reported was "infection," with 89.6% of studies reporting on this type of adverse event using 25 distinct terms. Other categories were "wound healing complications" (72.9% of papers, 38 terms), "bone/joint complications" (66.7% of papers, 35 terms), "hardware/implant complications" (56.3% of papers, 47 terms), "revision" (56.3% of papers, 35 terms), "cartilage/soft tissue injuries" (45.8% of papers, 31 terms), "reduction/alignment issues" (45.8% of papers, 29 terms), "medical complications" (43.8% of papers, 32 terms), "pain" (29.2% of papers, 16 terms), and "other complications" (20.8% of papers, 13 terms). There was a 78.6% interobserver agreement in the identification of terms across the 48 studies included.

CONCLUSION

The reporting terminology utilized to describe complications and adverse events in ankle fracture fixation was found to be highly variable and inconsistent. This variability prevents accurate reporting of complications and adverse events and makes the analysis of potential outcomes difficult. The development of standardized reporting terminology in orthopedics would be instrumental in addressing these challenges and allow for more accurate and consistent outcome reporting.

LEVEL OF EVIDENCE

Level III; systematic review of Level III studies and above.

Does Patient-Specific Instrumentation Have a Higher Rate of Early Osteolysis Than Standard Referencing Techniques in Total Ankle Arthroplasty? A Radiographic Analysis

Introduction: Patient-specific instrumentation (PSI) has been developed for total ankle arthroplasty (TAA), with proven benefits. One concern regarding PSI is the need for more soft tissue dissection in order to accurately position the PSI guides, which has the theoretical disadvantage of increased osteolysis. The purpose of our study is to compare the incidence and magnitude of osteolysis for the INFINITY Total Ankle System between PSI and standard referencing (SR) techniques. Methods: Sixty-seven patients who underwent primary TAA using Prophecy (PSI) or SR technique between 2013 and 2015 were reviewed in a retrospective observational study. Osteolysis was assessed on radiographs at 2 years. The incidence was calculated by binomial distribution. The number of zones compromised and the magnitude of osteolysis was calculated using the median as a summary statistic and interquartile range as dispersion statistic. Fisher exact test was used to compare both groups, then a regression model was estimated to calculate the odds ratio for osteolysis. Results: Of the 67 TAAs, 51 were in the PSI group and 16 in the SR group. In the PSI group the incidence, number of compromised zones (CZ), and magnitude was 41% (25%-59%), 1 [1-2], and 2 [2-3], respectively. In the SR group these were 36% (13%-65%), 3 [2-3], and 3 [2-4], respectively. No significant differences were found (P = .46, P = .12, P = .33). A slightly higher risk of osteolysis was found in the PSI group (odds ratio = 1.33 [0.36-4.83]) (P = .46). The majority of lesions were in 1 zone with size of 2 to 5 mm (63% for all cohort, 64% PSI, 60% SR). Two cases underwent revision for aseptic loosening, 1 in the SR group and 1 in the PSI group. Conclusion: According to our data, there is no significant difference between PSI and SR in terms of risk, incidence, size and magnitude of osteolysis in the INFINITY Total Ankle System at 2 years. Levels of Evidence: Therapeutic, Level III, Retrospective cohort study.

Positive and negative factors for the treatment outcomes following total ankle arthroplasty? A systematic review

BACKGROUND

Patient selection, surgeon's experience and implant design play an integral role and affect the treatment outcomes of total ankle arthroplasty (TAA). The aims of this study were to investigate the positive and negative attributes that correlate with different clinical and radiographic outcomes.

METHODS

Eight-nine studies matched the inclusion criteria: (1) studies of primary TAA with uncemented prosthesis; (2) mean follow-up of no less than 2-year; (3) reports of clinical and radiographic outcomes, and exclusion criteria: (1) non-English study; (2) more than one type of prosthesis without separated data; (3) kin studies with shorter follow-up or smaller cohort. Age, etiology, preoperative deformity, surgeon's experience, follow-up duration and prosthetic type were studied with respect to different outcomes by mixed-effects logistic regression analysis.

RESULTS

Patients factor: older patients reported less pain or stiffness and demonstrated less radiographic loosening which did not require additional surgical intervention. More traumatic arthritis experienced adjacent joints degeneration after TAA. Surgeon factor: less experienced surgeons had more intraoperative complications. Lack of experience for complications management without implant retrieval during early period might result in more revisions or fusion was done. Prosthetic factor: updated instrumentation decreased malalignment. If the polyethylene (PE) insert was significantly narrower than the metal components more implant instability and subsequent severe particulate wear was seen. Designs with flat-on-flat articulation and ridge at the center of the talar component associated with more PE fracture. Minimal bone resection reduced postoperative fractures. A flat cut of the tibial component and a flat undersurface with press-fit by two screws or pegs of the talar component demonstrated less postoperative fractures, whereas a syndesmosis fusion and a small triangular shape with one central fin of the talar component experienced more loosening which did not require additional surgery. Anatomic conical shape of the talar component seemed to reduce adjacent joint degeneration. Finally, fewer failures were found in patients who received HINTEGRA and Salto Talaris.

CONCLUSIONS

Based on our investigation, some positive and negative factors for different clinical and radiographic outcomes were found, which should be taken into consideration in clinical practice and ankle implant design.

Incidence and predictors of early complications following primary and revision total ankle arthroplasty

BACKGROUND

Total ankle arthroplasty (TAA) offers an effective option for end-stage osteoarthritis. The incidence and preoperative risk factors for early adverse events (AEs) following primary and revision TAA may be useful information for providers.

METHODS

A large database was queried from 2010 to 2016 to identify 905 patients of whom 818 underwent primary TAA (90.4%) and 87 underwent revision TAA (9.6%). Data on patient demographics, comorbidities, and hospital length of stay were analyzed as risk factors for reported 30-day AEs.

RESULTS

The overall AE rate was 5.5% (50/905) for the entire cohort. AEs occurred more frequently for revision TAA (9/87) than primary TAA (41/818) cases (OR 2.43, p=0.022). Age (OR 1.03, p=0.045), BMI (OR 1.04, p=0.046), and revision TAA (OR 2.56, p=0.002) were independent risk factors for 30-day AEs in multivariate analysis.

CONCLUSIONS

Older age, higher BMI, and revision cases are associated with a higher risk of AEs.

What Can We Expect Following Anterior Total Hip Arthroplasty on a Regular Operating Table? A Validation Study of an Artificial Intelligence Algorithm to Monitor Adverse Events in a High-Volume, Nonacademic Setting

BACKGROUND

Quality monitoring is increasingly important to support and assure sustainability of the orthopedic practice. Surgeons in nonacademic settings often lack resources to accurately monitor quality of care. Widespread use of electronic medical records (EMR) provides easier access to medical information, facilitating its analysis. However, manual review of EMRs is highly inefficient. Artificial intelligence (AI) software allows for the development of algorithms for extracting relevant complications from EMRs. We hypothesized that an AI-supported algorithm for complication data extraction would have an accuracy level equal to or higher than manual review after total hip arthroplasty (THA).

METHODS

A total of 532 consecutive patients underwent 613 THA between January 1 and December 31, 2017. A random derivation cohort (100 patients, 115 hips) was used to determine accuracy. After generation of a gold standard, the algorithm was compared to manual extraction to validate performance in raw data extraction. The full cohort (532 patients, 613 hips) was used to determine recall, precision, and F-value.

RESULTS

AI accuracy was 95.0%, compared to 94.5% for manual review (P = .69). Recall of 96.0% (84.0%-100%), precision of 88.0% (33%-100%) and F-measure of 0.85 (0.5-1) was achieved for all adverse events. No adverse events were recorded in 80.6%, 1.3% required reintervention and 18.1% had "transient" events.

CONCLUSION

The use of an automated, AI-supported search algorithm for EMRs provided continuous feedback on the quality of care with a performance level comparable to manual data extraction, but with greater speed. New clinical information surfaced, as 18.1% of patients can be expected to have "transient" problems.

Total Ankle Arthroplasty Survival and Risk Factors for Failure

BACKGROUND

Total ankle arthroplasty (TAA) is an increasingly selected treatment for end-stage ankle arthritis; however, failure and revision of the tibial and talar components remains an issue. Although multiple risk factors have been shown to contribute to early component revision, no study has looked at combining such risk factors into a predictive model that could potentially decrease revision rates and improve implant survival. This study aimed to develop a predictive model for TAA failure based on patient characteristics, patient-reported outcomes (PROs), and immediate postoperative radiographs.

METHODS

A retrospective review of a single-site ankle arthritis database was conducted. All patients with current-generation ankle replacements including the Hintegra and Infinity prostheses implanted between 2004 and 2015 and with complete postoperative radiographs taken between 6 and 12 weeks postoperatively were included. Eight coronal and sagittal radiographic parameters were assessed and performed twice by 2 independent orthopedic surgeons on included TAAs. These radiographic parameters were then analyzed in association with patient demographics and PRO. Advanced statistical methods including survival analysis were used to construct a predictive model for TAA survival. A total of 107 patients were included and analyzed with a median clinical follow-up of 49 months (minimum 24 months).

RESULTS

A predictive model was created, with 4 parameters identified as being statistically associated with TAA metal-component revision: diabetes mellitus, poor baseline Ankle Osteoarthritis Scale (AOS) score, excessively dorsiflexed talar component, and an anteriorly/posteriorly translated talus relative to the tibial axis. The presence of 3 parameters predicted TAA survival of 0.60 whereas presence of all 4 parameters predicted survival of only 0.13 in the period studied.

CONCLUSION

Our predictive model is based on a combination of patient factors, PROs, and radiographic TAA alignment. We believe it can be used by surgeons to predict failure in their TAA patients, thereby optimizing postoperative outcomes by improving patient selection and modifiable outcome-specific parameters.

LEVEL OF EVIDENCE

Level III, retrospective cohort study using prospectively collected data.

Comparison of cartilage and bone morphological models of the ankle joint derived from different medical imaging technologies

Background

Accurate geometrical models of bones and cartilage are necessary in biomechanical modelling of human joints, and in planning and designing of joint replacements. Image-based subject-specific model development requires image segmentation, spatial filtering and 3-dimensional rendering. This is usually based on computed tomography (CT) for bone models, on magnetic resonance imaging (MRI) for cartilage models. This process has been reported extensively in the past, but no studies have ever compared the accuracy and quality of these models when obtained also by merging different imaging modalities. The scope of the present work is to provide this comparative analysis in order to identify optimal imaging modality and registration techniques for producing 3-dimensional bone and cartilage models of the ankle joint.

Methods

One cadaveric leg was instrumented with multimodal markers and scanned using five different imaging modalities: a standard, a dual-energy and a cone-beam CT (CBCT) device, and a 1.5 and 3.0 Tesla MRI devices. Bone, cartilage, and combined bone and cartilage models were produced from each of these imaging modalities, and registered in space according to matching model surfaces or to corresponding marker centres. To assess the quality in overall model reconstruction, distance map analyses were performed and the difference between model surfaces obtained from the different imaging modalities and registration techniques was measured.

Results

The registration between models worked better with model surface matching than corresponding marker positions, particularly with MRI. The best bone models were obtained with the CBCT. Models with cartilage were defined better with the 3.0 Tesla than the 1.5 Tesla. For the combined bone and cartilage models, the colour maps and the numerical results from distance map analysis (DMA) showed that the smallest distances and the largest homogeneity were obtained from the CBCT and the 3.0 T MRI via model surface registration.

Conclusions

These observations are important in producing accurate bone and cartilage models from medical imaging and relevant for applications such as designing of custom-made ankle replacements or, more in general, of implants for total as well as focal joint replacements.

Peri-prosthetic bone cysts after total ankle replacement. A systematic review and meta-analysis

BACKGROUND

Periprosthetic cystic osteolysis is a well-known complication of total ankle replacement. Several theories have been proposed for its aetiology, based on individual biomechanical, radiological, histopathology and outcome studies.

METHODS

Studies that met predefined inclusion/exclusion criteria were analysed to identify literature describing the presence of peri-prosthetic ankle cystic osteolysis. Quantitative data from the selected articles were combined and statistically tested in order to analyse possible relations between ankle peri-prosthetic bone cysts and specific implant characteristics.

RESULTS

Twenty-one articles were elected, totalizing 2430 total ankle replacements, where 430 developed peri-prosthetic cystic osteolysis. A statistically significant association (P<.001) was found between the presence of bone cysts and non-anatomic implant configuration, hydroxyapatite-coating, mobile-bearing and non tibial-stemmed implants. No significant association existed between the type of constraining and the presence of cysts (P>.05).

CONCLUSIONS

Non-anatomic, mobile-bearing, hydroxyapatite-coated and non tibial-stemmed total ankle replacements are positively associated with more periprosthetic bone cysts.

Incorporating patients' perspectives into the initial stages of core outcome set development: a rapid review of qualitative studies of type 2 diabetes

Conducting systematic reviews of qualitative studies to incorporate patient perspectives within the early stages of core outcome set (COS) development can be resource intensive. We aimed to identify an expedited approach to be used as part of the wider COS development process. Specifically, we undertook a rapid review of qualitative studies of patients' views and experiences of type 2 diabetes. We searched MEDLINE from inception to June 2017 to identify studies reporting qualitative empirical findings of perspectives of people with type 2 diabetes. Qualitative methodological filters were used to minimize irrelevant references. Drawing on content analysis, data synthesis involved identifying text in eligible studies relevant to outcomes of type 2 diabetes and interpreting and categorizing this according to the 38 core domains of the Core Outcome Measures in Effectiveness Trials taxonomy. Of 146 studies screened, 26 were included. Four hundred and fifty-eight outcomes were derived from the included studies. In comparison to the outcomes extracted from clinical trials, more life impact outcomes were derived from the qualitative studies, but fewer physiological/clinical outcomes. Outcomes relating to 'mortality/survival' and 'role functioning' were more prevalent in studies conducted in low/middle-income countries. This rapid review and synthesis of qualitative studies identified outcomes that had not previously been identified by a systematic review of clinical trials. It also identified differences in the types of outcomes given prominence to in the clinical trials and qualitative literatures. Incorporating qualitative evidence on patient perspectives from the outset of the COS development process can help to ensure outcomes that matter to patients are not overlooked. Our method provides a pragmatic and resource-efficient way to do this. For those developing international COS, our method has potential for incorporating the perspectives of patients from diverse countries in the early stages of COS development.

Total ankle arthroplasty: what are the risks?: a guide to surgical consent and a review of the literature

AIMS

Total ankle arthroplasty (TAA) surgery is complex and attracts a wide variety of complications. The literature lacks consistency in reporting adverse events and complications. The aim of this article is to provide a comprehensive analysis of each of these complications from a literature review, and to compare them with rates from our Unit, to aid clinicians with the process of informed consent.

PATIENTS AND METHODS

A total of 278 consecutive total ankle arthroplasties (251 patients), performed by four surgeons over a six-year period in Wrightington Hospital (Wigan, United Kingdom) were prospectively reviewed. There were 143 men and 108 women with a mean age of 64 years (41 to 86). The data were recorded on each follow-up visit. Any complications either during initial hospital stay or subsequently reported on follow-ups were recorded, investigated, monitored, and treated as warranted. Literature search included the studies reporting the outcomes and complications of TAA implants.

RESULTS

There were wound-healing problems in nine ankles (3.2%), superficial infection in 20 ankles (7.2%), and deep infection in six ankles (2.2%). Intraoperative fractures occurred in medial malleoli in 27 ankles (9.7%) and in lateral malleoli in four ankles (1.4%). Aseptic loosening and osteolysis were seen 16 ankles (5.8%). Fracture of the polyethylene component occurred in one ankle (0.4%) and edge-loading in seven ankles (2.5%). We observed medial gutter pain in 31 ankles (11.1%). The incidence of thromboembolism occurred in two ankles (0.7%). The results were found to be comparable to the previously reported complications of total ankle arthroplasty in the literature.

CONCLUSION

Total ankle arthroplasty continues to evolve and improve the ankle function. Despite high overall complication rates with TAA surgery, most complications appear to be minor and do not affect final clinical outcome. Our results and literature review will help in the consent process and provide detailed complication rates for an informed consent. Cite this article: Bone Joint J 2018;100-B:1352-8.

Frequency and Impact of Adverse Events in Patients Undergoing Surgery for End-Stage Ankle Arthritis

BACKGROUND

This study summarized the frequency and functional impact of adverse events (AEs) that occur after surgery for end-stage ankle arthritis (ESAA) to inform decision making.

METHODS

This was a multisite prospective cohort study to compare ankle arthroplasty to ankle arthrodesis in the treatment of ESAA among 6 participating sites. We compared the risk and impact of nonankle AEs and ankle-specific AEs versus no AEs controlling for potential confounding factors, including operative procedure using multinomial logistic regression. We estimated differences in postoperative functional outcomes by AE occurrence using linear mixed effects regression. Among 517 patients who had surgery for ankle arthritis and completed the full baseline assessment, follow-up scores were available in 494 (95%) patients.

RESULTS

There were a total of 628 reported AEs (477 in the arthroplasty group and 151 in the arthrodesis group). These occurred in 261 (63%) arthroplasty patients and 67 (65%) arthrodesis patients. There were 50 (8%) ankle-specific AEs. The risk of an ankle-specific AE was slightly higher in the arthrodesis group versus the arthroplasty group, odds ratio (OR) 1.84, 95% confidence interval (CI, 0.85, 3.98). The OR for the risk of non-ankle-specific AE versus no AE was 0.96, 95% CI (0.57, 1.61) for those receiving arthrodesis compared to arthroplasty. Compared to patients with no AEs, those experiencing ankle-specific AEs had significantly less improvement in Foot and Ankle Ability Measure Sports and activities of daily living (ADL) subscores and worst pain outcomes; however, both groups improved significantly in all measures except mental health.

CONCLUSIONS

Ankle-specific AEs were infrequent and only weakly associated with operative procedure. Although patients improved in all functional outcomes except mental health, regardless of AE occurrence, ankle-specific AEs negatively impacted patient improvement compared to those with no AEs or a nonankle AE. The logistical effort and cost of tracking nonankle AEs does not seem to be justified.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Vancouver Foot and Ankle WNS (Wound, Nerve, and Systemic) Classification System for Foot and Ankle Orthopedic Surgery

BACKGROUND

Adverse events require consistent recording to determine the effect of alternate treatments. This study was undertaken to evaluate the Vancouver Foot and Ankle WNS complication scale to capture complications (W: wound, N: nerve, S: systemic) to assist in outcome recording.

METHODS

Interrater reliability was tested in 2 settings: (1) between 2 blinded clinicians in a live clinical setting and (2) between 8 orthopedic surgeons using case vignettes based on a retrospective analysis of 500 foot and ankle procedures performed at the Toronto Western Hospital, Department of Orthopaedics. The intrarater reliability of the WNS scale was tested in a single rater using the case vignettes. Inter- and intrarater reliability were assessed using the Fleiss and Cohen weighted kappa ( k), respectively and 95% confidence intervals (CIs). There was adequate power over 0.8.

RESULTS

In the live clinical setting, the Cohen weighted k (95% CI) values for the W (0.935 [0.862, 1.01]), N (0.914 [0.752, 1.08]), and S (1 [1, 1]) parameters, indicating a near perfect level of agreement between raters. In the broader community of professional foot and ankle surgeons, the Fleiss k values (95% CI) had moderate agreement for the W (0.712 [0.688, 0.735]), N (0.775 [0.738, 0.811]), and high agreement for S (0.834 [0.802, 0.866]) parameters based on case vignettes. However, the Fleiss k values continued to indicate moderate to strong agreement between raters for all parameters.

CONCLUSIONS

The WNS scale provided a standardized method of measuring foot and ankle surgical complications. There was at least moderate-strong interrater agreement for all parameters measured on case vignettes and excellent concordance in the live setting.

LEVEL OF EVIDENCE

Level III, comparative series.

Scandinavian Total Ankle Replacement: 15-Year Follow-up

BACKGROUND

Over the past decade, total ankle arthroplasty (TAA) has become a mainstay in the treatment of end-stage ankle arthritis. Currently in its fourth generation, the Scandanavian Total Ankle Replacement (STAR) is the only 3-piece mobile bearing ankle prosthesis available in the United States. Our current study reports implant survivorship at 15 years and patient outcomes for a subset of these survivors available for study.

METHODS

Eighty-four TAAs were performed between 1998 and 2000. Metal component survivorship at 15 years was calculated with a Kaplan-Meier curve. Twenty-four (29%) of 84 patients were available for participation with a minimum 15-year follow-up. Any radiographic changes were documented. All additional procedures and complications were recorded. Clinical findings, self-reported performance and pain evaluations, and AOFAS ankle/hindfoot scores were noted.

RESULTS

Metal implant survival was 73% at 15 years. Of the 24 patients available for clinical evaluation, 18 of 24 patients (70.7%) had no change in prosthetic alignment from the immediate postoperative radiograph. Only 1 subtalar fusion was required for symptomatic adjacent joint arthritis. Three patients sustained a broken polyethylene component. AOFAS scores improved from an average of 39.6 points preoperatively, to an average of 71.6. More than half (52.4%) of patients with retained implants required an additional surgical procedure; 3 required 2 additional procedures. The average time to subsequent procedure was 10.2 years.

CONCLUSION

Our small cohort demonstrated STAR ankles with retention at 9 years were highly likely to survive to 15 years, and patients continued to have significant improvement in pain relief and minimal decrease in function. At 15 years from TAA, metal survivorship was 73%. As with all ankle replacements, supplementary procedures were common.

LEVEL OF EVIDENCE

Level IV, case series.

A taxonomy has been developed for outcomes in medical research to help improve knowledge discovery

Objectives

There is increasing recognition that insufficient attention has been paid to the choice of outcomes measured in clinical trials. The lack of a standardized outcome classification system results in inconsistencies due to ambiguity and variation in how outcomes are described across different studies. Being able to classify by outcome would increase efficiency in searching sources such as clinical trial registries, patient registries, the Cochrane Database of Systematic Reviews, and the Core Outcome Measures in Effectiveness Trials (COMET) database of core outcome sets (COS), thus aiding knowledge discovery.

Study Design and Setting

A literature review was carried out to determine existing outcome classification systems, none of which were sufficiently comprehensive or granular for classification of all potential outcomes from clinical trials. A new taxonomy for outcome classification was developed, and as proof of principle, outcomes extracted from all published COS in the COMET database, selected Cochrane reviews, and clinical trial registry entries were classified using this new system.

Results

Application of this new taxonomy to COS in the COMET database revealed that 274/299 (92%) COS include at least one physiological outcome, whereas only 177 (59%) include at least one measure of impact (global quality of life or some measure of functioning) and only 105 (35%) made reference to adverse events.

Conclusions

This outcome taxonomy will be used to annotate outcomes included in COS within the COMET database and is currently being piloted for use in Cochrane Reviews within the Cochrane Linked Data Project. Wider implementation of this standard taxonomy in trial and systematic review databases and registries will further promote efficient searching, reporting, and classification of trial outcomes.

Medium to long-term results of 130 Ankle Evolutive System total ankle replacements-Inferior survival due to peri-implant osteolysis

BACKGROUND

The study reports the medium to long-term results of 130 Ankle Evolutive System total ankle replacements operated at a single-centre. Previously high amount of peri-implant osteolysis was reported from the same material.

METHODS

Between 2002 and 2008 one hundred and thirty consecutive ankles replaced with AES ankle prosthesis were followed both radiologically and clinically.

RESULTS

The five-year survival was 87.3% (95% confidence interval (CI) 80.0-92.0%), and ten-year survival 74.9% (95% confidence interval (CI) 65.4-82.2%) at a median follow-up time of 96 months (range 2-161; 8 years). Peri-implant osteolysis was found in 91 (70%) ankles, marked in 78 (60%). 44 ankles (34%) have been revised by filling of the cavities, 24 (18%) by fusion, and 6 by further replacement, resulting in the revision rate of 58%. Osteolysis was the main reason for all revisions. The improvement of the Kofoed Score and pain points was significant (all p<0.0001), and the subjective patient satisfaction was good.

CONCLUSIONS

Outcome of the current study was seriously affected by osteolysis and is inferior compared to previous reports.

Ankle Arthrodesis Versus Total Ankle Arthroplasty

Reoperation rates are higher in total ankle arthroplasties (TAAs) compared with ankle arthrodesis. Infection rates for primary TAAs are 1.4% to 2.4%. The survival rate of TAA is approximately 75% to 90% at 10 years. Arc of motion is maintained with TAAs compared with ankle arthrodesis. Ankle arthrodesis increases arc of motion through the talonavicular joint. Several factors are strong reasons to favor ankle fusion rather than TAA. TAA and ankle arthrodesis are effective treatments of end-stage ankle arthritis but the choice must be tailored to individual patients.

Is There Anything to Learn from a National Joint Registry?

National joint registries (NJRs) have been established in Northern Europe for over 20 years. Since then, many other countries have begun collecting and reporting national data for total ankle arthroplasty (TAA). With relatively small numbers implanted, a large variety of available designs, and with any long-term reports dominated by designer groups, TAA is ideally placed to benefit from large national or even pooled national registries. This article reviews the existing registry-based literature with respect to what is already known. The potential positives and down sides of registry data also are highlighted.

Operative Wound Complications Following Total Ankle Arthroplasty

BACKGROUND

Wound complications following total ankle replacement (TAR) potentially lead to devastating consequences. The aim of this study was to compare the operative and demographic differences in patients with and without major wound problems which required operative management. We hypothesized that increased tourniquet and operative time would negatively influence wound healing.

METHODS

We identified a consecutive series of 762 primary TARs performed between December 1999 and April 2014 whose data were prospectively collected. We then identified the subset of patients who required a secondary surgery to treat major wound complications (ie, operative debridement, split-thickness skin grafting, and soft tissue reconstruction). All patients requiring a second surgery had operative wound debridement. We then compared the demographics, operative characteristics, and functional scores to see if any differences existed between patients with and without major wound complications. Clinical outcomes including secondary procedures and implant failure rates were recorded.

RESULTS

Twenty-six patients (3.4%) had a total of 49 operative procedures to treat major wound issues. Eighteen patients had flaps and 14 had split-thickness skin grafts. The median time to operatively treating the wound was 1.9 (range: 0.5-12.5) months after the index TAR. The median follow-up time from the wound procedure was 12.7 (range: 1.2-170.8) months. Compared to the control group, patients with major wounds had a significantly longer mean surgery (214.8 vs 189.3 minutes, P = .041) time and trended toward a longer median tourniquet time (151 vs 141 minutes, P = .060). Patients without wound complications were more likely to have posttraumatic arthritis, whereas those with wound complications were more likely to have primary osteoarthritis ( P = .006). The control group trended toward having a higher mean BMI (29.5 vs 27.2, P = .056). There were 6 failures in the major wound complication cohort (23.1%), including 2 below the knee amputations.

CONCLUSION

Ankle wounds that required operative management had high failure rates and some resulted in devastating outcomes. We did not find any increase in major wound complications in those with various risk factors as identified by other studies. Given our data, we recommend limiting operative time. While correcting hindfoot and midfoot alignment is important for improving patient functionality and survivorship of the implant, thought should be given to staging the TAR if multiple pathologies are to be addressed at the time of surgery to limit operative time.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Iatrogenic Arteriovenous Fistula With Associated Pseudoaneurysm of Posterior Tibial Artery After Revision Total Ankle Arthroplasty: A Case Report

Iatrogenic vascular injuries in elective orthopedic surgery are rare. However, these are important complications to recognize early and treat appropriately because the potential sequelae can be devastating. Arteriovenous fistula of the lower extremity after total ankle arthroplasty has not been previously described in published studies. The proper diagnosis of arteriovenous fistulas can be difficult without a high index of suspicion, and treatment often involves surgical intervention. We present the case of a 62-year-old male who developed an iatrogenic arteriovenous fistula with associated pseudoaneurysm of the posterior tibial artery after revision total ankle arthroplasty that was treated with surgical ligation and excision, followed by reverse saphenous vein grafting.

A Coding System for Reoperations Following Total Ankle Replacement and Ankle Arthrodesis

BACKGROUND

Repeated surgery can be a measure of failure of the primary surgery. Future reoperations might be avoided if the cause is recognized and procedures or devices modified accordingly. Reoperations result in costs to both patient and the health care system. This paper proposes a new classification system for reoperations in end-stage ankle arthritis, and analyzes reoperation rates for ankle joint replacement and arthrodesis surgeries from a multicenter database.

METHODS

A total of 213 ankle arthrodeses and 474 total ankle replacements were prospectively followed from 2002 to 2010. Reoperations were identified as part of the prospective cohort study. Operating reports were reviewed, and each reoperation was coded. To verify inter- and intraobserver reliability of this new coding system, 6 surgeons experienced in foot and ankle surgery were asked to assign a specific code to 62 blinded reoperations, on 2 separate occasions. Reliability was determined using intraclass correlation coefficients (ICCs) and proportions of agreement.

RESULTS

Of a total of 687 procedures, 74.8% (514/687) required no reoperation (Code 1). By surgery type, 14.1% (30/213) of ankle arthrodesis procedures and 30.2% (143/474) of ankle replacement procedures required reoperation. The rate for reoperations surrounding the ankle joint (ie, Codes 2 and 3) was 9.9% (21/213) for ankle arthrodesis versus 5.9% for ankle replacement (28/474). Reoperation rates within the ankle joint (ie, Codes 4 to 10) were 4.7% (10/213) for ankle arthrodesis and 26.1% (124/474) for ankle replacement. Overall, 0.9% (2/213) of arthrodesis procedures required reoperation outside the initial operative site (Code 3), versus 4.6% (22/474) for total ankle replacement. The rate of reoperation due to deep infection (Code 7) was 0.9% (2/213) for arthrodesis versus 2.3% (11/474) for ankle replacement. Interobserver reliability testing produced a mean ICC of 0.89 on the first read. The mean ICC for intraobserver reliability was 0.92. For interobserver, there was 87.9% agreement (804/915) on the first read, and 87.5% agreement (801/915) on the second. For the intra observer readings, 88.5% (324/366) were in agreement.

CONCLUSIONS

The new coding system presented here was reliable and may provide a more standardized, clinically useful framework for assessing reoperation rates and resource utilization than prior complication- and diagnosis-based classification systems, such as modifications of the Clavien Dindo System. Analyzing reoperations at the primary site may enable a better understanding of reasons for failure, and may therefore improve the outcomes of surgery in the future.

LEVEL OF EVIDENCE

Level III, retrospective comparative cohort study based on prospectively collected data.