Foot & Ankle International

Tendinopathy is a debilitating tendon disorder that affects millions of Americans and costs billions of health care dollars every year. High mobility group box 1 (HMGB1), a known tissue damage signaling molecule, has been identified as a mediator in the development of tendinopathy due to mechanical overloading of tendons in mice. Metformin (Met), a drug approved by the Food and Drug Administration used for the treatment of type 2 diabetes, specifically inhibits HMGB1. This study tested the hypothesis that Met would prevent mechanical overloading-induced tendinopathy in a mouse model of tendinopathy created by intensive treadmill running (ITR).

C57BL/6J mice (female, 3 months old) were equally separated into 4 groups and treated for 24 weeks as follows: group 1 had cage control activities, group 2 received a single intraperitoneal injection of Met (50 mg/kg body weight) daily, group 3 underwent ITR to induce tendinopathy, and group 4 received daily Met injection along with ITR to inhibit HMGB1. Tendinopathic changes were assessed in Achilles tendons of all mice using histology, immunohistochemistry, and enzyme-linked immunosorbent assays.

ITR induced HMGB1 release into the tendon matrix and developed characteristics of tendinopathy as evidenced by the expression of macrophage marker CD68, proinflammatory molecules (COX-2, PGE₂), cell morphological changes from normal elongated cells to round cells, high levels of expression of chondrogenic markers (SOX-9, collagen type II), and accumulation of proteoglycans in tendinopathic tendons. Daily injection of Met inhibited HMGB1 release and decreased these degenerative changes in ITR tendons.

Inhibition of HMGB1 by injections of Met prevented tendinopathy development due to mechanical overloading in the Achilles tendon in mice.

Met may be able to be repurposed as a therapeutic option for preventing the development of tendinopathy in high-risk patients.

There is controversy regarding the effectiveness of postoperative antibiotics to prevent wound infection. Some surgeons still use a routine postoperative oral antibiotic regimen. The purpose of this study was to review a series of cases and document statistically any difference in infection rates and whether routine postoperative antibiotics in foot and ankle surgery are justified.

A retrospective chart review of 649 patients was performed who underwent elective foot and ankle surgery. Six hundred thirty-one patient charts were included in the final analysis. Evaluated were patients who did and did not receive postoperative oral antibiotics in order to identify whether a difference in infection rate or wound healing occurred. The study also evaluated risk factors for developing infection following foot and ankle surgery.

The number of infections in patients receiving postoperative oral antibiotics was 6 (3%), while the number of infections in those who did not receive postoperative oral antibiotics was 10 (2%) (P = .597). The difference of deep versus superficial infections and delays in wound healing between the 2 groups was not statistically significant. Patients who developed infections were older and had a higher prevalence of hypertension, a history of neoplasm, and a greater American Society of Anesthesiologists Classification of Physical Health.

This study suggests that routine use of postoperative antibiotics in foot and ankle surgery does not affect wound complications or infection rates. Additionally, patients who are older and those with multiple medical problems may be at higher risk for developing postoperative infection following foot and ankle surgeries.

Level III, retrospective comparative series.

Morton’s neuroma (MN) is often a diagnostic dilemma lacking a gold standard set of diagnostic criteria. Advanced imaging of MN is evolving including ultrasonography. The current study aimed to analyze the relationship between ultrasonographic findings and symptoms, clinical data, and operative findings in a subgroup of patients.

We evaluated physical examination, ultrasonographic findings, symptoms, and in a subgroup, the operative findings for Morton’s neuroma. We analyzed the symptoms, the findings on physical examination, and ultrasonography data and performed a statistical correlation between them. A total of 175 patients were seen for suspected Morton’s neuroma during the last 7 years.

Neuropathic pain of the toes was reported in 63% of patients. Presence of ultrasonographic findings suggesting Morton’s neuroma was observed in 77% of cases. A mild significant relationship between neuropathic pain and positive ultrasonographic findings was observed. We found a strong correlation between ultrasonographic and clinical evaluation, but more than half with clinical negative Morton’s neuroma had positive findings at ultrasonography. In the subgroup of operatively treated patients (n = 44) surgery confirmed Morton’s neuroma in all patients who had positive ultrasonography findings.

The current study suggests that the association of ultrasonographic evaluation and clinical evaluation can be very useful for the management of Morton’s neuroma. Our study could help with the development of a multiperspective approach in the diagnosis of Morton’s neuroma.

Level II, prospective cohort survey study.

The open anterior approach to ankle arthrodesis offers a technique that provides several advantages for surgeons, such as easier visualization of the joint for deformity correction and preservation of the malleoli for potential future conversion to total ankle arthroplasty. The purpose of this study was to evaluate clinical, radiographic, and functional outcomes in a large series of patients undergoing open ankle arthrodesis via a fibular-sparing anterior approach.

A retrospective review was performed of patients undergoing primary ankle arthrodesis with a single fellowship-trained foot and ankle orthopedic surgeon between 2009 and 2017. Patients were excluded if an approach other than anterior was performed. Patient-reported outcome measures (Foot and Ankle Ability Measure–Activities of Daily Living [FAAM-ADL], Short-Form 12 [SF-12], and visual analog scale [VAS] pain) were subsequently collected at a minimum of 24 months (2 years) following index surgery, along with outcome satisfaction and likelihood to repeat surgery. Fusion of the tibiotalar joint at the time of last radiographic follow-up was also assessed. Paired t tests were performed to assess change in pre- to postoperative outcomes, while linear regression analysis was performed to identify any patient factors associated with outcomes. Eighty-one patients, including 31 women and 50 men, with a mean age of 51.5 years and a mean follow-up of 58.9 (range, 24-104) months, were included.

Sixty-two patients reported significant improvement in mean FAAM-ADL (P < .0001), SF-12 Physical Composite Scale (P < .0001), and VAS pain (P < .0001), while the SF-12 Mental Composite Scale also improved, though not significantly (P = .2854). Twelve patients (14.8%) experienced complications following their arthrodesis procedure. Seventy-nine patients (97.5%) achieved fusion at their last radiographic follow-up. Multiple linear regression analysis revealed age (B = 0.071 [0.004, 0.128]; P = .0373) to have a positive association with postoperative VAS pain.

Ankle arthrodesis utilizing a fibular-sparing anterior approach combined with the transarticular screw fixation technique offers surgeons several advantages, along with a low postoperative complication rate, high rate of radiographic evidence of joint fusion, and substantially large improvement in pain and functional levels.

Level IV, retrospective case series.

Foot and ankle surgery often requires bone healing, whether in elective arthrodesis or trauma. While primary bone healing is possible, the rate of nonunion in foot and ankle surgery remains variable. The addition of autogenous bone graft can allow for higher union rates by adding to the biology at the site of bone healing. Harvesting autogenous bone graft from the calcaneus for foot and ankle surgery can be done quickly and efficiently and allow for an adequate amount of graft.

A retrospective chart and radiographic review was performed for 1438 patients at a single center between August 1, 2015, and December 15, 2018, who underwent calcaneal autograft harvesting using a power-driven reaming graft harvester.

In total, 966 patients were included and evaluated for the safety and complication rate associated with the procedure. Only 1 patient (0.1%) had a major complication, and there were 14 minor complications (1.4%).

The safety profile and low complication rate of this case series demonstrate that this simple and efficient calcaneal autograft harvest technique can be considered when a small to moderate amount of autogenous bone graft is required to augment bone healing.

Therapeutic level IV, case series.

The Kidner procedure is performed to treat painful accessory navicular syndrome, with varying results. Recurrent pain remains a complication, and to date, there is a paucity of literature regarding the causes of recurrent pain and surgical outcomes of revision.

Twenty-one patients who underwent revision surgery for recurrent pain after the Kidner procedure were identified. All patients had their tendon inspected and treated, and all had a medial displacement calcaneal osteotomy. Revision was indicated after 6 months of failed conservative therapy. Pre- and postrevision radiographic measurements included lateral talo–first metatarsal angle (Meary’s angle), talonavicular coverage angle, calcaneal pitch, and hindfoot moment arm (HMA). Meary’s angle >4 degrees was considered a planus deformity and HMA >9.1 mm was considered a hindfoot valgus deformity; patients fulfilling both criteria were categorized as having planovalgus deformity. Measurements in the contralateral foot were performed to determine whether alignment of the involved side was attributed to failed treatment or a preexisting deformity. Visual analog scale and Foot and Ankle Outcome Scores were compared and average follow-up was 20.1 months (range, 14-26).

Preoperatively, 20 of 21 (95%) patients had a form of valgus heel alignment (planovalgus, n = 11; hindfoot valgus only, n = 9), and 1 had an isolated planus deformity. The contralateral side revealed similar deformity, with 17 of 21 (81%) patients having a form of valgus heel alignment (planovalgus, n = 13; hindfoot valgus only, n = 4) and 4 patients with an isolated planus deformity. All patients underwent realignment surgery with medial displacement calcaneal osteotomy. All radiographic parameters except Meary’s angle (P = .885) significantly improved postoperatively along with significantly improved clinical outcomes.

Recurrent pain following the Kidner procedure was associated with valgus heel alignment. Revision surgery including realignment procedure alleviated pain and improved functional outcomes with minimal complications. Therefore, we recommend assessing heel alignment in patients presenting with recurrent pain following the Kidner procedure.

Level IV, case series.

The midline-incision trans-achillary approach (MITA) is frequently used for addressing all pathologies of insertional Achilles tendinopathy (IAT). The aim of this study was to assess the complication rate and possible influencing factors following a MITA for IAT treatment.

Presented is a retrospective cohort study with current follow-up. Patients treated surgically by a MITA, addressing all pathologies of IAT, between January 2010 and October 2016 at a single reference center with at least 12 months of follow-up were included. General demographics (age, sex, and body mass index), medical history, surgical details (individual and sum of pathologies addressed), and duration of in-hospital stay were assessed. Patient satisfaction, shoe conflict, current employment status, time to return to sports, and type of sports were recorded using a custom questionnaire. Standard statistics, chi-square, and t tests were performed using SPSS. A total of 118 patients (follow-up, 63.4%) with a mean age (± SD) of 50 ± 12 years and a mean final follow-up time (± SD) of 4.2 ± 2.1 were included.

Fourteen percent of patients had a minor complication, the majority (75%) of which were surgical site infections. Forty-one percent were limited in their shoe selection, and 32% reported a shoe conflict. Seventy-eight percent were very satisfied, and 89% would recommend the surgery. Neither the individual surgical procedures, their sum, nor any other parameter showed a significant influence on the complication rate. The only factor negatively affecting patient satisfaction was a shoe conflict (P < .001).

The MITA for IAT treatment showed a moderate minor complication rate with good midterm patient satisfaction. However, the approach might predispose patients to shoe conflict, which negatively influences their satisfaction.

Level IV, retrospective cohort study.

Treatment of failed total ankle arthroplasty (TAA) is challenging. Limited literature is available on options and outcomes of revision arthroplasty despite failure rates ranging from 10% to 23% within 10 years after primary TAA. This study reports the clinical and radiographic outcomes of revision TAA using a fixed-bearing, intramedullary-referencing implant.

A retrospective review was performed of 18 consecutive revision TAA cases between 2008-2015 using an intramedullary-referencing, fixed-bearing, 2-component total ankle system. Demographic and radiographic data were collected preoperatively, immediately postoperatively, and at the most recent follow-up. Functional outcome data were collected immediately postoperatively and at mean follow-up 47.5 months.

Eighteen patients underwent revision TAA, with 77.8% (14/18) implant survival. Index revision was performed most commonly for aseptic talar subsidence (55.6%) or implant loosening (tibia, 29.4%; talus, 58.9%). Following revision, 22.2% (4/18) patients required reoperation at a mean 57.3 (39-86) months. Osteolysis of the tibia, talus, and fibula was present preoperatively in 66.7% (12/18), 38.9% (7/18), and 38.9% (7/18) of patients, respectively, with progression of osteolysis in 27.8% (5/18), 11.1% (2/18) and 11.1% (2/18) of patients, respectively. Subsidence of the tibial and talar revision components was observed in 38.9% (7/18) and 55.6% (10/18) of patients, respectively. The median American Orthopaedic Foot & Ankle Society (AOFAS) score was 74.5 (26-100) and Foot Function Index (FFI) score 10.2 (0-50.4).

Early results of intramedullary-referencing revision TAA demonstrated good patient-reported outcomes with maintenance of radiographic parameters at mean follow-up of 47.5 months. Aseptic talar subsidence or loosening were the main postoperative causes of reoperation. Revision arthroplasty utilizing an intramedullary-referencing implant was a viable option for the failed TAA.

Level IV, case series.

The Salto Talaris is a fixed-bearing implant first approved in the US in 2006. While early surgical outcomes have been promising, mid- to long-term survivorship data are limited. The aim of this study was to present the survivorship and causes of failure of the Salto Talaris implant, with functional and radiographic outcomes.

Eighty-seven prospectively followed patients who underwent total ankle arthroplasty with the Salto Talaris between 2007 and 2015 at our institution were retrospectively identified. Of these, 82 patients (85 ankles) had a minimum follow-up of 5 (mean, 7.1; range, 5-12) years. The mean age was 63.5 (range, 42-82) years and the mean body mass index was 28.1 (range, 17.9-41.2) kg/m². Survivorship was determined by incidence of revision, defined as removal/exchange of a metal component. Preoperative, immediate, and minimum 5-year postoperative AP and lateral weightbearing radiographs were reviewed; tibiotalar alignment (TTA) and the medial distal tibial angle (MDTA) were measured to assess coronal talar and tibial alignment, respectively. The sagittal tibial angle (STA) was measured; the talar inclination angle (TIA) was measured to evaluate for radiographic subsidence of the implant, defined as a change in TIA of 5 degrees or more from the immediately to the latest postoperative lateral radiograph. The locations of periprosthetic cysts were documented. Preoperative and minimum 5-year postoperative Foot and Ankle Outcome Score (FAOS) subscales were compared.

Survivorship was 97.6% with 2 revisions. One patient underwent tibial and talar component revision for varus malalignment of the ankle; another underwent talar component revision for aseptic loosening and subsidence. The rate of other reoperations was 21.2% (n = 18), with the main reoperation being exostectomy with debridement for ankle impingement (n = 12). At final follow-up, the average TTA improved 4.4 (± 3.8) degrees, the average MDTA improved 3.4 (± 2.6) degrees, and the average STA improved 5.3 (± 4.5) degrees. Periprosthetic cysts were observed in 18 patients, and there was no radiographic subsidence. All FAOS subscales demonstrated significant improvement at final follow-up.

We found the Salto Talaris implant to be durable, consistent with previous studies of shorter follow-up lengths. We observed significant improvement in radiographic alignment as well as patient-reported clinical outcomes at a minimum 5-year follow-up.

Level IV, retrospective case series.

Talus avascular necrosis (AVN) is a challenging entity to treat. Management options depend on disease severity and functional goals. Total talus replacement (TTR) is a treatment option that maintains joint range of motion. The literature on TTR is limited with variability in implant design and material. The purpose of this study was to evaluate outcomes following TTR with a custom 3D printed metal implant.

Patients who underwent TTR were retrospectively reviewed over a 3-year period. Basic demographic data and comorbidities were collected. Medical records were reviewed to obtain postoperative and preoperative visual analog scale (VAS) scores, Foot and Ankle Outcome Scores (FAOSs), ankle range of motion, and postoperative complications. Statistical analysis was conducted to compare clinical and patient-reported outcomes pre- and postoperatively. Twenty-seven patients underwent TTR for talar AVN with a mean follow-up of 22.2 months.

Ankle range of motion remained unchanged postoperatively. VAS pain scores improved postoperatively from 7.1 to 3.9 (P < .001). FAOSs improved postoperatively with regard to pain (P < .001), symptoms (P = .001), quality of life (P < .001), and activities of daily living (P < .001). There were 3 complications requiring reoperation in this cohort.

3D printed TTRs represent a unique surgical option for patients with severe talar AVN. Patients in this cohort demonstrated significant improvements in pain scores and patient-reported outcomes. TTR allows for symptomatic improvement with the preservation of motion in individuals with talar collapse and AVN.

Level IV, retrospective case series.

Proper implant selection and placement is crucial during fixation of zone II and III fifth metatarsal fractures to avoid postoperative complications. This study examined the effects of screw parameters and placement on malreduction, delayed union, nonunion, and refracture rate.

A retrospective review of zone II and proximal zone III fifth metatarsal fractures managed with intramedullary screw fixation was conducted. Comparisons were made between cortex distraction (gap) and ratios of screw length, diameter, and entry point. Further analysis was carried out between time to union and distraction in the lateral and plantar cortices.

The plantar and lateral gaps were both associated with the mean entry point ratio on the lateral and anteroposterior (AP) views (P < .001 for both views). No association between the plantar and lateral gaps and the screw diameter ratio (P = .393 for AP and P = .981 for lateral) or the screw length ratio (P = .966 for AP and P = .740 for lateral) was identified. The ratio of postoperative to preoperative apex height on AP and lateral views was correlated with the presence of lateral and plantar fracture gaps (P < .001). The presence of a plantar gap was associated with increased time to union (P = .022). A majority of fractures showed radiographic union at 12 weeks (38/43). Only 5 of 38 patients had delayed union. There were no refractures or nonunions as per available records.

Plantar or lateral fracture site distraction (gap) was not influenced by screw diameter ratio or screw length ratio. The entry point ratio had a significant effect on plantar and lateral gaps on postoperative radiographs, with lateral and inferior placement leading to fracture site distraction. Patients with a plantar gap did have an increased risk of delayed union. The results of this study emphasize the significance of the entry point when managing zone II and III fifth metatarsal base fractures.

Level IV, case series.

The anterior talofibular ligament and the calcaneofibular ligament are 2 of the most frequently injured structures in sports, being damaged in 30% to 45% of all sports injuries. Most reconstructive procedures are successful but can deteriorate with time and can lead to low-grade radiographic degeneration.

We operated on 26 consecutive patients from 2001 to 2008 who had failed previous surgical procedures for the lateral ligamentous complex of the ankle, with an average of 104 (range, 75-140) months.

The overall functional rating was excellent in 14 ankles, good in 10, fair in 1, and poor in 1. Twenty-four patients (92.3%) were satisfied with the procedure and 15 (57.7%) were able to return to their preinjury level of activity. Local complications were detected in 2 patients who presented with skin necrosis; 1 patient developed severe reflex sympathetic dystrophy.

Revision surgery for the management of failure after surgical treatment of chronic lateral ankle instability is under debate, and the literature is devoid of clinical studies with long-term follow-up. The technique described offers a high rate of long-term excellent and good results, with a low rate of complications and a good rate of return to preinjury level.

Level IV, retrospective case series.

In preaxial polydactyly of the foot, the choice for excision of the lateral or medial hallux is not straightforward, in particular with proximal phalangeal (type IV) and metatarsal (type VI) duplication, because of anatomical characteristics. We evaluated whether medial or lateral hallux excision gives better outcomes in these duplication types, to help clinical decision making.

Children with type IV or type VI duplication (n=14, age: 4.4-17.2 years), who were operatively treated by excision of the lateral or medial hallux, were assessed for foot function using plantar pressure measurements and clinical examination. Foot aesthetics were scored by the child, an expert, and 10 laypersons, and additional patient-reported outcome questionnaires were obtained. Outcomes were compared between lateral and medial excision, per duplication type.

In type IV duplication (n=11), lateral excision showed a better distribution of peak pressure between the hallux and first metatarsal with significantly lower median first metatarsal peak pressure (P = .008). Lateral excision showed more medial hallux deviation (P = .017). Foot aesthetics were not different between excision sides. In type VI duplication (n=12), lateral excision showed a 59% higher hallux peak pressure, larger medial hallux deviation (P = .004), and more reoperations. Foot aesthetics were scored significantly better after lateral excision by experts and laypersons.

Foot function by virtue of plantar pressure was better after lateral hallux excision in type IV and after medial hallux excision in type VI duplication. Surgeons and laypersons perceived the foot as more normal after lateral excision in type VI, whereas children reported no differences. These outcomes can be used in clinical decision making.

Level III, therapeutic, comparative study.

This study was designed to investigate the incidence and hematological biomarker levels that are associated with deep venous thrombosis (DVT) following closed foot fractures (except calcaneal fractures).

A retrospective analysis of data on patients presenting with closed foot fractures (excluding the calcaneus) between October 2014 and December 2018 was conducted. Duplex ultrasonography was used to screen preoperative DVT of bilateral lower extremities. Data on demographics, comorbidities, types of fracture, and laboratory biomarkers at admission were collected. Univariate analyses and multivariate logistic regression analyses were carried out to determine the independent risk factors associated with DVT.

A total of 537 patients were included, among whom 28 patients had preoperative DVTs, indicating a crude incidence rate of 5.2%. In isolated closed foot fractures, DVT occurred in 12 (2.9%) out of 410 patients, while in patients with concurrent fracture in other locations, 16 (12.6%) out of 127 patients developed DVT. The average interval between fracture occurrence and diagnosis of DVT was 4.2 days (median, 2 days), ranging from 0 to 17 days. Twenty-four patients (85.7%) developed DVT in the injured extremity, 3 (10.7%) in the uninjured extremity, and 1 (3.5%) in bilateral extremities. Seven risk factors were identified to be associated with DVT, including alcohol consumption, concomitant other fractures, platelet distribution width (PDW) <12%, high-density lipoprotein cholesterol (HDL-C) <1.1mmol/L, serum alkaline phosphatase (ALP) >100 U/L, serum sodium concentration (Na⁺) <135 mmol/L, and D-dimer >0.5 mg/L.

Being aware of the prevalence of DVT in closed foot fractures can help physicians to carry out the overall assessment, risk stratification, and individual prevention programs.

Level III, a prospective cohort study.