Foot & Ankle International

The Ankle Arthritis Score (AAS) is a new patient-reported outcome derived from the Ankle Osteoarthritis Scale (AOS). This study analyzed longitudinally collected data from a cohort of patients in the Canadian Orthopaedic Foot and Ankle Society (COFAS) Ankle Arthritis Study in order to evaluate whether the postoperative AAS is associated with need for revision surgery.

A multicenter, prospective, ankle-reconstruction study enrolled 653 ankles undergoing total ankle replacement (TAR) or ankle arthrodesis (AA). The AAS was given at baseline and annually during postoperative follow-up. Time to revision surgery was modeled using a proportional hazards model. The final sample included 531 ankles in 509 patients.

Sixty-two patients underwent metal-component revision and 8 underwent arthrodesis revision during the follow-up time period. The remaining 461 unrevised ankles (300 TAR, 161 AA) had a minimum follow-up of 2 years (average of 3.4 years). Revision surgery after TAR was found to be associated with a higher postoperative AAS and a longer follow-up. The hazard ratio for the AAS indicated that for every 1-point increase in the score, the rate of revision surgery after TAR was 1 percentage point higher.

TAR patients who reported higher levels of postoperative functional impairment, as indicated by a higher AAS, were more likely to require metal-component revision surgery. After adjustment for other patient factors, the risk of revision surgery increased with length of follow-up after TAR. This study provides further evidence for the utility of the AAS in the clinical setting.

Level III, retrospective cohort study.

The effectiveness of corticosteroid injection for the treatment of Morton’s neuroma is unclear. In addition, most of the studies related to it are case-control or retrospective case series. The purpose of this study was to compare the effectiveness between corticosteroid injection associated with local anesthetic and local anesthetic alone (placebo control group) for the treatment of Morton’s neuroma.

Forty-one patients with a diagnosis of Morton’s neuroma were randomized to receive 3 injections of either a corticosteroid plus a local anesthetic or a local anesthetic alone. The patients and the researcher who collected data were blinded to the treatment groups. The visual analog scale for pain and the American Orthopaedic Foot & Ankle Score (metatarsophalangeal/interphalangeal score) were obtained at baseline, after each injection, and at 3 and 6 months after the last injection.

There were no significant between-group differences in terms of pain and function improvement at 3 and 6 months after treatment completion in comparison with baseline values. At the end of the study, 17 (48.5%) patients requested surgical excision of the neuroma: 7 (44%) in the experimental group and 10 (53%) in the control group (P = 1.0).

The injection of a corticosteroid plus a local anesthetic was not superior to a local anesthetic alone in terms of pain and function improvement in patients with Morton’s neuroma.

Level I, randomized controlled trial.

Persistent pain despite a total ankle replacement is not uncommon. A main source of pain may be an insufficiently balanced ankle. An alternative to the revision of the existing arthroplasty is the use of a corrective osteotomy of the distal tibia, above the stable implant. This strictly extraarticular procedure preserves the integrity of the replaced joint. The aim of this study was to review a series of patients in whom a corrective supramalleolar osteotomy was performed to realign a varus misaligned tibial component in total ankle replacement. We hypothesized that the supramalleolar osteotomy would correct the malpositioned tibial component, resulting in pain relief and improvement of function.

Twenty-two patients (9 male, 13 female; mean age, 62.6 years; range, 44.7-80) were treated with a supramalleolar osteotomy to correct a painful ankle with a varus malpositioned tibial component. Prospectively recorded radiologic and clinical outcome data as well as complications and reoperations were analyzed.

The tibial anterior surface angle significantly changed from 85.2 ± 2.5 degrees preoperatively to 91.4 ± 2.9 degrees postoperatively (P < .0001), the American Orthopaedic Foot & Ankle Society hindfoot score significantly increased from 46 ± 14 to 66 ± 16 points (P < .0001) and the patient’s pain score measured with the visual analog scale significantly decreased from 5.8 ± 1.9 to 3.3 ± 2.4 (P < .001). No statistical difference was found in the tibial lateral surface angle and the range of motion of the ankle when comparing the preoperative to the postoperative measurements. The osteotomy healed in all but 3 patients on first attempt. Fifteen patients (68%) were (very) satisfied, 4 moderately satisfied, and 3 patients were not satisfied with the result.

The supramalleolar osteotomy was found to be a reliable treatment option for correcting the varus misaligned tibial component in a painful replaced ankle. However, nonunion (14%) should be mentioned as a possible complication of this surgery. Nonetheless, as a strictly extraarticular procedure, it did not compromise function of the previously replaced ankle, and it was shown to relieve pain without having to have revised a well-fixed ankle arthroplasty.

Level IV, case series.

There are 2 Level I studies comparing open reduction and internal fixation (ORIF) and primary arthrodesis (PA) in high-energy Lisfranc injuries. There are no studies comparing ORIF and PA in young athletic patients with low-energy injuries.

All operatively managed low-energy Lisfranc injuries sustained by active duty military personnel at a single institution were identified from 2010 to 2015. The injury pattern, method of treatment, and complications were reviewed. Implant removal rates, fitness test scores, return to military duty rates, and Foot and Ankle Ability Measure (FAAM) scores were compared. Thirty-two patients were identified with the average age of 28 years. PA was performed in 14 patients with ORIF in 18.

The PA group returned to full duty at an average of 4.5 months whereas the ORIF group returned at an average of 6.7 months (P = .0066). The PA group ran their fitness test an average of 9 seconds per mile slower than their preoperative average whereas the ORIF group ran it an average of 39 seconds slower per mile (P = .032). There were no differences between the 2 groups in the FAAM scores at an average of 35 months. Implant removal was performed in 15 (83%) in the ORIF group and 2 (14%) in the PA group (P = .005).

Low-energy Lisfranc injuries treated with primary arthrodesis had a lower implant removal rate, an earlier return to full military activity, and better fitness test scores after 1 year, but there was no difference in FAAM scores after 3 years.

Level III, comparative cohort study.

Lisfranc injuries result from high- and low-energy mechanisms though the literature has been more focused on high-energy mechanisms. A comparison of high-energy (HE) and low-energy (LE) injury patterns is lacking. The objective of this study was to report injury patterns in LE Lisfranc joint injuries and compare them to HE injury patterns.

Operative Lisfranc injuries were identified over a 5-year period. Patient demographics, mechanism of injury, injury pattern, associated injuries, missed diagnoses, clinical course, and imaging studies were reviewed and compared. HE mechanism was defined as motor vehicle crash, motorcycle crash, direct crush, and fall from greater than 4 feet and LE mechanism as athletic activity, ground level twisting, or fall from less than 4 feet. Thirty-two HE and 48 LE cases were identified with 19.3 months of average follow-up.

There were no differences in demographics or missed diagnosis frequency (21% HE vs 18% LE). Time to seek care was not significantly different. HE injuries were more likely to have concomitant nonfoot fractures (37% vs 6%), concomitant foot fractures (78% vs 4%), cuboid fractures (31% vs 6%), metatarsal base fractures (84% vs 29%), displaced intra-articular fractures (59% vs 4%), and involvement of all 5 rays (23% vs 6%). LE injuries were more commonly ligamentous (68% vs 16%), with fewer rays involved (2.7 vs 4.1).

LE mechanisms were a more common cause of Lisfranc joint injury in this cohort. These mechanisms generally resulted in an isolated, primarily ligamentous injury sparing the lateral column. Both types had high rates of missed injury that could result in delayed treatment. Differences in injury patterns could help direct future research to optimize treatment algorithms.

Level III, comparative series.

A most challenging condition for balancing a varus arthritic ankle is the presence of a defect in the medial tibial plafond. After our initial results with a medial tibial plafondplasty did not fulfill our expectations of success, we hypothesized that adding a correcting supramalleolar osteotomy of the distal tibia would move the loading force to the tibiotalar joint more medially and move the center of rotation of the talus more laterally. In this study, we analyzed midterm clinical and radiographic outcomes in patients with double tibial osteotomy.

Between January 2005 and February 2010, 20 patients were treated with a medial tibial plafondplasty and a medial supramalleolar osteotomy of the distal tibia. The mean age of the patients was 44 ± 12 years (range, 17-60 years). Follow-up averaged 5.9 ± 2.1 years (range, 4-11.2 years). Weight-bearing radiographs were used to assess osteotomy union and hindfoot alignment.

There were no intraoperative or perioperative complications. The average VAS pain score decreased significantly from 7.9 ± 1.3 (range, 6-10) to 1.3 ± 1.6 (range, 0-7). The average AOFAS hindfoot score increased significantly from 49 ± 15 points (range, 36-68) preoperatively to 86 ± 12 points (range, 66-96) postoperatively. The varus tilt improved significantly from 19.4° ± 8.2° (range, 6°-32°) to 6.9° ± 3.9° (range, 1°-12°).

The novel double osteotomy was found to be an efficient and successful method to restore tibiotalar joint congruency and to normalize hindfoot alignment.

Level IV, prospective cohort study.

The purpose of the study was to determine when patients can safely return to driving after first metatarsal osteotomy for hallux valgus correction.

After institutional review board approval, 60 patients undergoing right first metatarsal osteotomy for hallux valgus correction surgery were recruited prospectively. Patients’ brake reaction time (BRT) was tested at 6 weeks and repeated until patients achieved a passing BRT. A control group of twenty healthy patients was used to establish as passing BRT. Patients were given a novel driver readiness survey to complete.

At 6 weeks, 51 of the 60 patients (85%) had BRT less than 0.85 seconds and were considered safe to drive. At 6 weeks, the passing group average was 0.64 seconds. At the 8 weeks, 59 patients (100%) of those who completed the study achieved a passing BRT. Patients that failed at 6 weeks had statistically greater visual analog scale (VAS) pain score and diminished first metatarsophalangeal (MTP) range of motion (ROM). On the novel driver readiness survey, 8 of the 9 patients (89%) who did not pass disagreed or strongly disagreed with the statement, “Based on what I think my braking reaction time is, I think that I am ready to drive.”

Most patients may be informed that they can safely return to driving 8 weeks after right metatarsal osteotomy for hallux valgus correction. Some patients may be eligible to return to driving sooner depending on their VAS, first MTP ROM, and driver readiness survey results.

Level II, comparative study

Unstable ankle fractures require treatment with open reduction and internal fixation (ORIF). Long-term functional outcome is satisfying in most patients; however, a number of patients have persistent complaints. Superficial nerve complications following ankle surgery may be the cause of chronic pain and disability.

In this observational retrospective survey, a cohort of 527 women and men, who underwent ORIF in the period from January 2007 to January 2014, were invited to an online questionnaire. Pain symptoms were assessed using the McGill Pain Questionnaire (MPQ) and the Douleur Neuropathic en 4 Questions (DN4) Questionnaire. Descriptive statistics were used to present patient characteristics; a logistic regression model was used to analyze prognostic factors of neuropathic pain. A total of 271 patients completed the questionnaire. Mean follow-up period was 5.8 years (±1.9).

Persistent neuropathic pain symptoms were present in 61 of all patients, and 51 of these patients reported an impaired quality of life caused by their symptoms. In univariate analysis, the following parameters were associated with neuropathic pain: age, hypertension, a thyroid disorder, lower back pain, fracture dislocations, and late complications such as nonunion, posttraumatic arthritis, or osteochondral injury. In multivariate analysis, an age between 40 and 60 years was found to be a significant predictor of neuropathic pain. Hypertension, dislocation, and late complications were significant predictors of persistent pain without neuropathic characteristics.

The present study demonstrated a prevalence of persistent neuropathic pain symptoms after ORIF for ankle fractures in 23% of the respondents, which caused an impaired health-related quality of life. We identified 4 significant predictors of chronic and neuropathic pain after ORIF. This knowledge may aid the treating surgeon to identify patients who are at increased risk of persistent postoperative neuropathic pain and may affect the treatment of pain in these patients.

Level IV, retrospective case series.

Ankle fractures are among the most prevalent traumatic orthopaedic injuries. A large proportion of patients sustaining operative ankle fractures are admitted directly from the emergency department prior to operative management. In the authors’ experience, however, many closed ankle injuries may be safely and effectively managed on an outpatient basis. The aim of this study was to characterize the economic impact of routine inpatient admission of ankle fractures.

A retrospective review of all outpatient ankle fracture surgery performed by a single foot and ankle fellowship–trained surgeon at a tertiary level academic center in 2012 was conducted to identify any patients requiring postoperative inpatient admission. The National Inpatient Sample was queried for operative management of lateral malleolus, bimalleolar, and trimalleolar ankle fractures in 2012 with regard to national estimates of total volume and length of stay by age. The maximum allowable Medicare inpatient facility reimbursements for diagnosis related group 494 and Medicare outpatient facility reimbursements for Current Procedural Terminology codes 27792, 27814, and 27822 were obtained from the Medicare Acute Inpatient Prospective Pricer and the Medicare Outpatient Pricer Code, respectively. Private facility reimbursement rates were estimated at 139% of inpatient Medicare reimbursement and 280% of outpatient reimbursement, as described in the literature. Surgeon and anesthesiologist fees were considered similar between both inpatient and outpatient groups. A unique stochastic decision-tree model was derived from probabilities and associated costs and evaluated using modified Monte Carlo simulation.

Of 76 lateral malleolar, bimalleolar, and trimalleolar ankle fracture open reduction internal fixation cases performed in 2012 by the senior author, 9 patients required admission for polytrauma, medical comorbidities, or age. All 67 outpatients were discharged home the day of surgery. In the 2012 national cohort analyzed, 48,044 estimated inpatient admissions occurred postoperatively for closed ankle fractures. The median length of stay was 3 days for each admission and was associated with an estimated facility reimbursement ranging from $12,920 for Medicare reimbursement of lateral malleolus fractures to $18,613 for private reimbursement of trimalleolar fractures. Outpatient facility reimbursements per case were estimated at $4,125 for Medicare patients and $11,459 for private insurance patients. Nationally, annual inpatient admissions accounted for $796,033,050 in reimbursements, while outpatient surgery would have been associated with $419,327,612 for treatment of these same ankle fractures.

In the authors’ experience, closed lateral malleolus, bimalleolar, and trimalleolar fractures were safely and effectively treated on an outpatient basis. Routine perioperative admission of patients sustaining ankle fractures likely results in more than $367 million of excess facility reimbursements annually in the United States. Even if a 25% necessary admission rate were assumed, routine inpatient admission of ankle fractures would result in a $282 million excess economic burden annually in the United States. Although in certain cases, inpatient admission may be necessary, with value-based decision making becoming increasingly the responsibility of the orthopaedic surgeon, understanding the implications of inpatient stays for ankle fracture surgery can ultimately result in cost savings to the US health care system and patients individually.

Level III, comparative series.

The purpose of this study was to describe the incidence of plafond impaction in supination-adduction type II (SAD-II) ankle fractures and assess the accuracy of plain radiographs in detecting plafond impaction and predicting planned operative management compared to computed tomography (CT).

Patients with SAD-II ankle fractures were retrospectively identified. All SAD-II plain radiographs were reviewed (120 fractures) and compared to CT images (55 fractures). For each plain radiograph or CT scan, 3 orthopedic surgeons were asked the following questions: (1) Is there impaction of the tibial plafond? (2) Does the impaction require direct visualization and articular reduction? The incidence of plafond impaction and the preoperative plan were calculated separately for plain radiographs and CT scans. The accuracy of plain radiographs was calculated using responses from corresponding CT imaging as the gold standard. Change in preoperative management decisions after reviewing CT images was also calculated.

In 120 SAD-II ankle fracture plain radiographs, marginal impaction of the plafond was visualized in 61% of fractures. The diagnosis of impaction using plain radiographs was correct in 84% of fractures when compared to CT imaging, resulting in a 91% positive predictive value (PPV) and a 55% negative predictive value (NPV). Plain radiographs were able to predict planned operative management after review of CT imaging with an 87% PPV and 75% NPV.

The majority of SAD-II ankle fractures involved marginal impaction of the tibial plafond. Plain radiographs were accurate in diagnosing impaction when it was present, but were not accurate in ruling out impaction. In the presence of impaction, CT likely will not change planned operative management.

Level III, comparative series.

Equinovalgus deformity is the second most common deformity in cerebral palsy and may be flexible or rigid. Several operative methods from joint sparing to arthrodesis have been described with varying success rates. The aim of this study was to investigate the effectiveness of naviculectomy in combination with midfoot arthrodesis (talo-cuneiform and calcaneocuboid arthrodesis) in the correction of a rigid equinovalgus foot deformity in cerebral palsy.

Forty-eight rigid equinovalgus feet were operated upon in 30 patients from 2008 to 2013. Of these, 44 feet in 26 patients with cerebral palsy (Gross Motor Function Classification System III, IV, or V) with follow-up of more than 2 years were included in the study. The mean age at surgery was 18.1 years. The outcomes were measured objectively using radiographic angles and subjectively using 5 questions to be answered by the caregiver. The feet were then graded into excellent, good, fair, and poor. The mean follow-up was 5.0 ± 1.7 years.

Excellent to good results were obtained in 81% of the feet. Both objective and subjective outcomes improved significantly postoperatively (P < .001). Three feet in 2 patients were graded as poor and underwent a revision operation for pain and recurrence.

Naviculectomy in combination with midfoot arthrodesis enabled a good 3-dimensional correction of the forefoot. However, the procedure did not necessarily correct the fixed subtalar joint deformity. Several additional bony and soft-tissue procedures were necessary to achieve a complete correction in these difficult feet.

Level IV, retrospective case series.

Although standard fixation of proximal interphalangeal (PIP) arthrodesis by K-wire is relatively inexpensive and well established, it does have some drawbacks, making newer fixation devices interesting. The aim of this study was to clinically and radiologically assess the operative correction of the lesser toe deformation in the form of a PIP arthrodesis using a bioabsorbable 2.7-mm fixation screw.

From January 2011 until October 2013, 34 patients underwent a PIP arthrodesis using the TRIM-IT (Arthrex) 2.7-mm fixation screw and were contacted for this retrospective cohort study. At an average of 3.3 years after the operation, 24 patients and 26 toes were evaluated clinically, radiologically, through pedobarography, and a patient-satisfaction survey.

Using the PLLA screw for fixation, 84.6% showed bony union of the arthrodesis, and 84.6% were satisfied. Mean AOFAS score was 82.7 points and thus regarded as good. The mean VAS score was 1.3/10. Overall, 73.1% of the toes showed good alignment, and 7.7% had a painless recurrence of deformity and were still satisfied with the intervention. In addition, 34.6% had floating toes, but only 4.2% without Weil osteotomy or encroachment. Further, 3.8% were advised to undergo a revision because of severe misalignment.

The 2.7-mm bioabsorbable fixation screw yielded results that were comparable to other fixation devices for PIP fusion fixation regarding success rate, revisions, and patient acceptance.

Level IV, retrospective case series.

Aseptic component loosening is a leading cause of revision for total ankle replacement. Different operative approaches for resecting the tibia and talus impact the bony support for the prostheses due to variations in both bone density and resection area, and may therefore impact loosening performance.

Computed tomography data from 116 subjects were obtained, and solid models of the talus and tibia were generated. Bone density, resection area, and bony support were measured on a series of flat resections for each subject, at multiple resection depths. Similar measurements were performed using a series of subject-specific, anatomic radius–based resections (“round resections”) at multiple depths. Results were compared to assess the impact of both resection type (flat vs round) and resection depth (6-16 mm for the tibia, 2-6 mm for the talus) on bony support.

Statistically significant decreases in bony support for both the talus and the tibia were obtained for flat resections as compared to round resections. A decrease of 8% to 19% for the tibia was seen for all resection depths; a decrease of 8% to 46% for the talus was seen, with greater decreases seen for shallower flat-cut resections.

Bony support in total ankle arthroplasty may be decreased using flat resections compared to round resections at comparable resection depths. Estimated differences are resection-level dependent and different for the distal tibia vs the proximal talus.

Biomechanical characteristics of total ankle replacement impacted by bony support of the prostheses, including implant stability and resistance to subsidence, may be improved with round resections as compared to flat-cut resections.

Total ankle replacement (TAR) and ankle arthrodesis (AA) are usually performed for severe ankle arthritis. We compared postoperative foot segmental motion during gait in patients treated with TAR and AA.

Gait analysis was performed in 17 and 7 patients undergoing TAR and AA, respectively. Subjects were evaluated using a 3-dimensional multisegmental foot model with 15 markers. Temporal gait parameters were calculated. The maximum and minimum values and the differences in hallux, forefoot, hindfoot, and arch in 3 planes (sagittal, coronal, transverse) were compared between the 2 groups. One hundred healthy adults were evaluated as a control.

Gait speed was faster in the TAR (P = .028). On analysis of foot and ankle segmental motion, the range of hindfoot sagittal motion was significantly greater in the TAR (15.1 vs 10.2 degrees in AA; P = .004). The main component of motion increase was hindfoot dorsiflexion (12.3 and 8.6 degrees). The range of forefoot sagittal motion was greater in the TAR (9.3 vs 5.8 degrees in AA; P = .004). Maximum ankle power in the TAR (1.16) was significantly higher than 0.32 in AA;P = .008). However, the range of hindfoot and forefoot sagittal motion was decreased in both TAR and AA compared with the control group (P = .000).

Although biomechanical results of TAR and AA were not similar to those in the normal controls, joint motions in the TAR more closely matched normal values. Treatment decision making should involve considerations of the effect of surgery on the adjacent joints.

Level III, case-control study.