Mid- to long-term outcome of 96 corrective hindfoot fusions in 84 patients with rigid flatfoot deformity

Isolated Subtalar Repositional Arthrodesis Compared With Triple Arthrodesis for the Treatment of Progressive Collapsing Foot Deformity

The optimal extent of arthrodesis for severe and rigid progressive collapsing foot deformity is controversial. Traditionally, triple arthrodesis has been recommended; however, good results have been reported using subtalar arthrodesis only. We compared the results of triple arthrodesis and isolated subtalar repositional arthrodesis. A total of 22 symptomatic feet were evaluated retrospectively. Isolated subtalar repositional arthrodesis was performed in 13 cases (the subtalar group) and double or triple arthrodesis in 9 cases (the triple group). Various radiographic variables for assessing flatfoot and osteoarthritic changes in ankle and tarsal joints were measured and compared between the 2 groups at 3 time points: preoperatively, 3 months postoperatively, and 4 y postoperatively. Additionally, we analyzed various factors that affect postoperative valgus talar tilt in the ankle joint, which has been associated with poor prognosis. There were no differences in preoperative demographic data and the severity of the disease between the 2 groups; both groups showed improvement in radiographic parameters postoperatively compared with preoperative results. With the numbers available, no significant differences could be detected in postoperative radiographic measurements between the 2 groups. Of all the variables analyzed, postoperative hindfoot alignment angle was associated with postoperative talar tilt development. Additionally, postoperative talar tilt was observed more in triple group than in subtalar group. In conclusion, isolated subtalar repositional arthrodesis is an effective procedure to correct advanced progressive collapsing foot deformity. In addition, Chorpart joint arthrodesis with improper position can cause valgus talar tilt in the ankle joint.

Does foot shape really matter? Correlation of patient reported outcomes with radiographic assessment in progressive collapsing foot deformity reconstruction: A systematic review

BACKGROUND

In progressive collapsing foot deformity (PCFD), the goal of surgery is to obtain a well-balanced plantigrade foot. It remains unclear if restoration of the alignment and subsequent improvement in radiological parameters is associated with improved patient-reported outcome measures (PROMs). The aim of the current systematic review was to investigate whether there is a correlation between radiographic assessment and PROMs in patients treated surgically for flexible PCFD.

MATERIALS AND METHODS

The study was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. A comprehensive literature search was performed in Pubmed, EMBASE, Cochrane Central Register of Controlled Trails (CENTRAL), and KINAHL. We included all the studies reporting both PROMs and radiological outcomes in patients treated surgically for PCFD. The quality of the included studies was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal tool.

RESULTS

Six retrospective studies were included. Radiological parameters related to forefoot plantarflexion were associated with statistically significant differences in postoperative PROMs. A neutral hindfoot and midfoot position was positively correlated with postoperative PROMs but a statistically significant difference could not be established in all studies. The medial arch height was positively correlated with PROMs, but in one study this was the case only in revision surgeries.

CONCLUSION

The literature so far suggests restoration of the alignment may be associated with improved PROMs. Future prospective studies that investigate possible radiological and clinical correlations in PCFD surgery are needed.

LEVEL OF EVIDENCE

III.

Retrospective Review of Complications and Revision Rates Between Isolated Talonavicular vs Talonavicular and Subtalar (Double) Arthrodesis vs Triple Arthrodesis

Background

Hindfoot fusion procedures are common for the treatment of end-stage arthritis or deformity. Surgical treatments for these conditions include talonavicular joint (single) arthrodesis, talonavicular and subtalar (double) arthrodesis, or talonavicular, subtalar, and calcaneocuboid (triple) arthrodesis. This study evaluated the complication rate, revision surgery rate, and hardware removal rate for those treated with either single, double, or triple arthrodesis.

Methods

A retrospective review was conducted for patients who underwent single (Current Procedural Terminology [CPT] code 28740), double (CPT 28725 and 28740), or triple (CPT 28715) arthrodesis to treat hindfoot arthritis/deformity (International Classification of Diseases, Ninth Revision [ICD-9] code: 734, International Classification of Diseases, Tenth Revision [ICD-10] codes: M76821, M76822, and M76829) from 2005 to 2022 using the South Carolina Revenue and Fiscal Affairs databank. Data collected included demographics, comorbidities, procedure data, and postoperative outcomes within 1 year of principal surgery. Student t test, chi-squared test, and multivariable logistic regression analysis were utilized during data analysis.

Results

A total of 433 patients were identified, with 248 undergoing single arthrodesis, 67 undergoing double arthrodesis, and 118 undergoing triple arthrodesis. There was no significant difference between single, double, and triple arthrodesis in the rate of complications, hardware removals, revision surgeries, or 30-day readmission when controlling for confounding variables. However, a decrease in Charlson Comorbidity Index (CCI) was found to be predictive of an increase in the revision surgery rate (OR = 0.46, 95% CI 0.22-0.85, P = .02).

Conclusion

We found no difference in the rate of complications, hardware removals, or revision surgeries in those undergoing single, double, or triple arthrodesis. Surprisingly we found that a lower Charlson Comorbidity Index, indicating a healthier patient had a significant relationship with a higher rate of revision surgery. Further study including radiographic indications for surgery or the impact of overall health status on revision surgery rates may further elucidate the other components of this relationship.

Level of Evidence

Level III, cohort study.

Incidence and predictors of valgus tibiotalar tilt after progressive collapsing foot deformity reconstruction using subtalar fusion with concomitant procedures

PURPOSE

Development of valgus tibiotalar tilt is a significant complication after subtalar fusion for progressive collapsing foot deformity (PCFD) correction. However, its incidence and etiologic factors have not been extensively studied. The purpose of this study was to define the incidence of valgus tibiotalar tilt after subtalar fusion for PCFD reconstruction, and to determine predictors of this complication.

METHODS

This study included 59 patients who underwent PCFD reconstruction with subtalar fusion. Patients with tibiotalar tilt prior to surgery were excluded. On standard weightbearing radiographs, the talonavicular coverage angle, talo-1st metatarsal angle, calcaneal pitch, hindfoot moment arm (HMA), and medial distal tibial angle were measured. Weightbearing computed tomography (WBCT) was used to determine the presence of lateral bony impingement. A radiologist evaluated the superficial and deep deltoid ligaments using magnetic resonance imaging (MRI). Univariate regression analysis was used to identify the factors associated with development of postoperative valgus tibiotalar tilt, defined as tilt > 2 degrees.

RESULTS

Seventeen patients (28.8%) developed postoperative valgus tibiotalar tilt at a mean of 7.7 (range 2-31) months. Eight (47.1%) of these patients developed valgus tibiotalar tilt within 3 months. Univariate logistic regression demonstrated association between preoperative HMA and postoperative valgus tibiotalar tilt (odds ratio 1.06, P = 0.026), with a 6% increase in risk per millimeter of increased HMA. Deltoid ligament status and concomitant procedures on other joints did not correlate with postoperative valgus tilt.

CONCLUSION

Our findings indicate that surgeons should be cognizant of patients with a greater degree of preoperative hindfoot valgus and their propensity to develop a valgus ankle deformity. Additionally, our relatively high incidence of valgus tibiotalar tilt suggests that weightbearing ankle radiographs should be included in the initial and subsequent follow-up of PCFD patients with hindfoot valgus treated with subtalar fusion.

Medial Double Arthrodesis Through Single Approach

Triple arthrodesis is a time-tested procedure toward primary salvage in the context of posterior tibial tendon dysfunction, symptomatic rigid and severe hindfoot malalignment, end-stage degenerative and posttraumatic arthritis, and sequelae of paralytic diseases. Today, the indication for hindfoot arthrodesis is applied to correct painful deformities and arthritic joints, such as advanced cases of adult-acquired flatfoot secondary to ligament collapse and insufficiency of the posterior tibial tendon. Although the triple arthrodesis is an effective and reliable outcome procedure, the popularity of a medial double arthrodesis has increased.

Surgical Considerations for Revision Flatfoot Reconstruction: Overcorrection/Undercorrection

Reconstructive surgery of the symptomatic pes planus deformity is a very common procedure with relatively good outcomes. Many factors such as patient selection, patient expectations, and surgical execution can influence the results. In addition to achieving osseous union, the overall postoperative alignment is critical in determining functional outcome. Specifically, under- and over-correction respectively present their own unique problems and symptomatology. The purpose of this review is to discuss the adverse outcomes after mal-reduction of flatfoot reconstruction and emphasize the strategies to correct the subsequent deformity.

Talo-navicular and calcaneo-cuboid fusion with PEEK H-pode™ vs. Titanium Maxlock™ locking plates: Comparison of functional and radiographic outcomes

BACKGROUND

Locking plates are increasingly used to achieve hindfoot fusion. The objective of this study was to compare hindfoot fusion outcomes with the PEEK H-pode™ (Biotech™) locking plate and the titanium Maxlock™ (Tornier-Wright™) locking plate.

HYPOTHESIS

A polyetheretherketone (PEEK) H-pode™ locking plate provides similar fusion rates to a titanium Maxlock™ locking plate for talo-navicular and calcaneo-cuboid arthrodesis.

METHODS

We conducted a retrospective comparative study in 39 patients (including 21 [54%] with pes planovalgus and 11 [28%] with neurological equinovarus deformities) who underwent talo-navicular and/or calcaneo-cuboid fusion, usually combined with subtalar fusion. The first 17 patients (January 2014-February 2016) were managed with Maxlock™ locking plates and the next 22 patients (March 2016-August 2018) with H-pode™ locking plates. These two cohorts of consecutive patients were comparable regarding age, sex distribution, body mass index, and comorbidities. At last follow-up more than 1year after surgery, we compared functional scores, pain intensity, and fusion assessed by radiographs and computed tomography (CT) (threshold set at 33%).

RESULTS

Mean follow-up was 42months (range: 34-63months) in the Maxlock™ group and 25months (range: 12-36months) in the H-pode™ group. At last follow-up, the two groups were not significantly different for the mean values of the American Orthopedic Foot & Ankle Society score, European Foot & Ankle Society score, and visual analogue scale pain score. Neither were the two groups significantly different for talo-navicular and calcaneo-cuboid fusion by CT. In the Maxlock™ group, we found non-significant trends towards a higher proportion of patients with talo-navicular nonunion (18% vs. 5% in the H-pode™ group) and weaker talo-navicular fusion in patients with pes planovalgus (60.8% vs. 82.0%, respectively). Radiographic results overestimated the fusion rates.

DISCUSSION

Talo-navicular and calcaneo-cuboid fusion was not significantly different with H-pode™ and Maxlock™ locking plates. CT was more accurate than standard radiography to assess fusion. These results underline the usefulness of PEEK locking plates for talo-navicular and calcaneo-cuboid fusion; moreover, the radiolucency of PEEK facilitates the interpretation of radiographs.

LEVEL OF EVIDENCE

IV.

Double Versus Triple Arthrodesis Fusion Rates: A Systematic Review

Hindfoot arthrodesis is often required for end-staged deformities, such as posterior tibial tendon dysfunction, osteoarthritis, or rheumatoid arthritis. Although the need for hindfoot arthrodesis is generally accepted in severe deformities, there is a debate whether a double or triple arthrodesis should be performed. The aim of our systematic review is to review the fusion rates and mean time to fusion in double and triple arthrodesis. A total of 184 articles were identified using the keyword search through the database of articles published from 2005 to 2017. After review by 3 physicians, a total of 13 articles met the eligibility criteria. The reason for double or triple arthrodesis within the studies were posterior tibial tendon dysfunction, tarsal coalition, degenerative joint disease, osteoarthritis, rheumatoid arthritis, Charcot Marie Tooth, Multiple Sclerosis, Polio, neuromuscular disorder, cerebral palsy, acrodystrophic neuropathy, clubfoot, post-traumatic, and seronegative arthropathy (spondyloarthritis). Within these 13 studies, there were a total of 343 (6-95) subjects extremities operated on. The overall fusion rate for double arthrodesis was 91.75% (289/315) compared to 92.86% (26/28) triple arthrodesis fusion rate, p value .8370. The mean time to fusion for double arthrodesis was 17.96 ± 7.96 weeks compared to 16.70 ± 8.18 weeks for triple arthrodesis, p value = .8133. There are risks associated with triple arthrodesis including increased surgical times, lateral wound complications, residual deformity, surgical costs and peri-articular arthritis. Given the benefits of double arthrodesis over triple arthrodesis and the nearly equivalent fusion rates and time to fusion, double arthrodesis is an effective alternative to triple arthrodesis. The authors of this systematic review recommend double arthrodesis as the hindfoot fusion procedure of choice.

Persistent Pain After Hindfoot Fusion

One of the most challenging problems facing orthopedic surgeons is persistent pain after surgery and certainly is just as frustrating following hindfoot fusion. The hindfoot joints consist of the subtalar, talonavicular, and calcaneocuboid (CC) joints. These joints are commonly fused for degenerative changes, deformity correction, inflammatory or neuropathic arthropathy, tarsal coalition, or primarily after trauma. Goals of hindfoot fusion are a painless plantigrade foot capable of fitting in shoes without orthotics or a brace. Many believe that deformity correction is achievable without inclusion of the CC joint. Managing patient expectations is important when counseling a patient especially regarding potential complications.

Fusion Versus Joint-Sparing Reconstruction for Patients With Flexible Flatfoot

AIMS

Passively correctible, adult-acquired flatfoot deformities (AAFD) are treated with joint-sparing procedures. Questions remain as to the efficacy of such procedures when clinical deformities are severe. In severe deformities, a primary fusion may lead to predictable outcomes, but risks nonunion. We evaluated pre- and postsurgical flexible AAFD patients undergoing joint-sparing or fusion procedures, comparing reoperation and complication rates.

METHODS

We identified patients with flexible AAFD between January 1, 2001 and 2016. Exclusion criteria were incomplete medical record, rigid AAFD, and prior flatfoot surgery. Patient demographics, pre- and postsurgical radiographic measurements, surgery performed, and postoperative complications were evaluated by bivariate analysis, comparing joint-sparing versus fusion procedures.

RESULTS

Of 239 patients (255 feet) (mean follow-up 62 ± 50 months), 209 (87%) underwent joint-sparing reconstructions, 30 (12.6%) underwent fusions. Fifty-four (24.1%) feet underwent joint-sparing reconstruction with reoperation versus 11 (35.5%) in fusion patients (P = .17). Radiographic improvement in talonavicular angle, talar first-metatarsal (anteroposterior view), and Meary's angle was higher in fusion patients (P < .001, P < .001, and P = .003, respectively).

DISCUSSION

More nonunion reoperations among fusion patients were offset by reoperations in joint-sparing patients. Fusion uniquely corrected Meary's angle. Nonunion is of less concern for joint-sparing versus fusion for patients with severe flexible AAFD. Degree of deformity versus advantage of joint motion should improve decision making.

LEVELS OF EVIDENCE

Level IV: Retrospective case series.

Evaluating Prospective Patient-Reported Pain and Function Outcomes After Ankle and Hindfoot Arthrodesis

Background:

Hindfoot and ankle fusions are mechanically limiting procedures for patients. However, patient-reported outcomes of these procedures have not been well studied. This study assessed outcomes of hindfoot and ankle fusions by using Patient-Reported Outcome Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) Computer Adaptive Tests (CATs).

Methods:

Between 2014 and 2018, 102 patients were prospectively enrolled after presenting to a tertiary care facility for ankle and hindfoot fusions, including tibiotalar, tibiotalocalcaneal, subtalar, and triple arthrodeses. Study participants completed preoperative and 12-month postoperative PF and PI CATs. The differences between mean 12-month postoperative and preoperative PROMIS PF and PI T scores were analyzed with paired t tests. The relationship between the 12-month PF and PI differences for the overall sample and patient factors was examined using multiple regression modeling.

Results:

The sample had mean age of 57.69 years; 48% were male, and 55% were obese. Patients who underwent ankle and hindfoot arthrodesis had statistically significant improvements from preoperative to 12 months postoperative in mean PF (36.26±7.85 vs 39.38±6.46, P = .03) and PI (61.07±7.75 vs 56.62±9.81, P = .02). Triple arthrodesis saw the greatest increases in physical function (▵PF = 7.22±7.31, P = .01) and reductions in pain (▵PI = –9.17±8.31, P = .01), achieving minimal clinically important difference (MCID). Patients who underwent tibiotalar fusion had significant improvement in physical function (▵PF = 4.18±5.68, P = .04) and pain reduction that approached statistical significance (▵PI = –6.24±8.50, P = .09), achieving MCID. Older age (≥60 years ) was associated with greater improvements in PF (β = 0.20, P = .07) and PI (β = –0.29, P = .04). Preoperative PF and PI T scores were significantly associated with the 12-month change in PF and PI T scores, respectively (β = –0.74, P < .01; β = –0.61, P < .01).

Conclusion:

Hindfoot and ankle fusions are procedures with favorable patient outcomes leading to increased physical function and decreased pain at 12 months postoperation relative to preoperation.

Level of Evidence:

Level II, prospective comparative study.

Calcaneal Osteotomies in the Treatment of Progressive Collapsing Foot Deformity. What are the Restrictions for the Holy Grail?

The progressive collapsing foot deformity is a complex three-dimensional deformity, including valgus malalignment of the heel. The medial displacement calcaneal osteotomy is an established surgical procedure reliably resulting in an efficient correction of the inframalleolar alignment. However, complications are common, including undercorrection of underlying deformity, progression of hindfoot osteoarthritis and/or deformity, and/or symptomatic hardware.

Is Arthrodesis Sufficient in the Setting of Complex, Severe and Rigid Progressive Collapsing Foot Deformities?

Arthrodesis of the hindfoot is typically used for the correction of severe and arthritic progressive collapsing foot deformity. Concomitant bony or soft tissue procedures may be helpful in patients with congenital abnormalities including the ball-and-socket ankle or congenital vertical talus. Dysplasia of the hindfoot bones may be more common than previously recognized, and corrective procedures or alterations in technique may need to be performed during hindfoot arthrodesis to account for bony deformity. Intraarticular osteotomies, extraarticular osteotomies, tendon lengthening, and tendon transfer procedures may be used in specific instances to aid in deformity correction and improve overall function.

Spring and Deltoid Ligament Insufficiency in the Setting of Progressive Collapsing Foot Deformity. An Update on Diagnosis and Management

The spring ligament and deltoid ligament are important stabilizers of the medial ankle. Together, they form a complex along the medial ankle and foot that is critical to stability of both the ankle and the medial longitudinal arch. Incompetence of the spring and deltoid ligament is a component of both the early and late stages of progressive collapsing foot deformity. As the importance of this medial ligament complex has been recognized, repair and reconstruction of these ligaments have progressively evolved, initially as separate reconstructions, and more recently as combined techniques.

Spare the Talonavicular Joint! The Role of Isolated Subtalar Joint Fusion in the Treatment of Progressive Collapsing Foot Deformity

Surgical management of progressive collapsing foot deformity continues to evolve. Previous studies have demonstrated that fusion of the talonavicular joint results in limited hindfoot motion and, therefore, may accelerate adjacent-joint arthrosis. Recent literature has supported using alternative arthrodesis constructs that spare the talonavicular joint, such as naviculocuneiform or isolated subtalar fusions, which may maintain some hindfoot motion through the talonavicular joint yet adequately address a patient's deformity. Concomitant reconstructive procedures may be used in addition to subtalar fusion to address severe deformities. Isolated subtalar fusions may be considered in cases of sinus tarsi or subfibular impingement deformities.

Imaging of Peritalar Instability

Undiagnosed medial ankle instability can be a prerequisite for pathogenic progression in the foot, particularly for adult acquired flatfoot deformity. With the complex anatomy in this region, and the limitations of each individual investigational method, accurately identifying peritalar instability remains a serious challenge to clinicians. Performing a thorough clinical examination aided by evaluation with advanced imaging can improve the threshold of detection for this condition and allow early proper treatment to prevent further manifestations of the instability.

Double hindfoot arthrodesis using a single-incision medial approach in the correction of adult-acquired flatfoot deformity: a case series

BACKGROUND

Hindfoot arthrodesis is used in patients with advanced-stage acquired flatfoot, usually associated with degenerative joint disease. The objective of the present study was to evaluate the clinical and radiographic results of hindfoot arthrodesis using the single-incision medial approach.

METHODS

A case series of 18 consecutive patients undergoing surgical correction between 2015 and 2018 with hindfoot arthrodesis using the medial approach was evaluated. The clinical assessment used the visual analog pain scale, AOFAS hindfoot score, SF-36, and foot function index. Radiographs and personal satisfaction criteria were also analyzed.

RESULTS

All radiographic parameters evaluated showed a significant improvement (p < .05), except the calcaneal pitch. Pain decreased by 5.1 points (p < .001), and the mean final AOFAS score was 72.6. In three feet, a new surgery was required. Two feet developed talar necrosis. None of the cases presented surgical wound dehiscence, and two presented with superficial infection, which was resolved with the use of oral antibiotics.

CONCLUSION

Double arthrodesis (subtalar and talonavicular) to correct adult-acquired valgus flatfoot using a medial approach has a low risk of soft tissue complications and presents satisfactory functional results. Avascular necrosis is a serious complication that was present in 11% of cases.

American College of Foot and Ankle Surgeons Clinical Consensus Statement: Appropriate Clinical Management of Adult-Acquired Flatfoot Deformity

This clinical consensus statement of the American College of Foot and Ankle Surgeons focuses on the highly debated subject of the management of adult flatfoot (AAFD). In developing this statement, the AAFD consensus statement panel attempted to address the most relevant issues facing the foot and ankle surgeon today, using the best evidence-based literature available. The panel created and researched 16 statements and generated opinions on the appropriateness of the statements. The results of the research on this topic and the opinions of the panel are presented here.

Consensus on Indications for Isolated Subtalar Joint Fusion and Naviculocuneiform Fusions for Progressive Collapsing Foot Deformity

RECOMMENDATION

Peritalar subluxation represents an important hindfoot component of progressive collapsing foot deformity, which can be associated with a breakdown of the medial longitudinal arch. It results in a complex 3-dimensional deformity with varying degrees of hindfoot valgus, forefoot abduction, and pronation. Loss of peritalar stability allows the talus to rotate and translate on the calcaneal and navicular bone surfaces, typically moving medially and anteriorly, which may result in sinus tarsi and subfibular impingement. The onset of degenerative disease can manifest with stiffening of the subtalar (ST) joint and subsequent fixed and possibly arthritic deformity. While ST joint fusion may permit repositioning and stabilization of the talus on top of the calcaneus, it may not fully correct forefoot abduction and it does not correct forefoot varus. Such varus may be addressed by a talonavicular (TN) fusion or a plantar flexion osteotomy of the first ray, but, if too pronounced, it may be more effectively corrected with a naviculocuneiform (NC) fusion. The NC joint has a curvature in the sagittal plane. Thus, preserving the shape of the joint is the key to permitting plantarflexion correction by rotating the midfoot along the debrided surfaces and to fix it. Intraoperatively, care must be also taken to not overcorrect the talocalcaneal angle in the horizontal plane during the ST fusion (eg, to exceed the external rotation of the talus and inadvertently put the midfoot in a supinated position). Such overcorrection can lead to lateral column overload with persistent lateral midfoot pain and discomfort. A contraindication for an isolated ST fusion may be a rupture of posterior tibial tendon because of the resultant loss of the internal rotation force at the TN joint. In these cases, a flexor digitorum longus tendon transfer is added to the procedure.

LEVEL OF EVIDENCE

Level V, consensus, expert opinion.

Minimally invasive technique for stage III adult-acquired flatfoot deformity: a mid- to long-term retrospective study

PURPOSE

The purpose of this study was to present the functional, radiological, and quality of life outcomes of a series of stage III adult-acquired flatfoot deformity corrections using an original operative approach based on minimal incision surgery (MIS).

METHODS

Sixty-two patients (67 feet) with a symptomatic stage III flatfoot deformity were treated using a modified double arthrodesis by MIS. The mean age was 63 years (range, 50 to 81) and the mean follow-up was 6.6 years (range, 3.2 to 11.5). Clinical, radiological, American Orthopaedic Foot and Ankle Society Hindfoot score (AOFAS score), quality of life (SF-36), and satisfaction scores were collected retrospectively.

RESULTS

The mean AOFAS score improved by 54.27 (95% [CI], 57.27-51.3; P < 0.0001), and the SF-36 improved by a mean of 17.5 points (95% CI, 1.4-20.9) in the physical component summary (PCS). Deformity correction was confirmed by a significant improvement in the x-ray measurements (six angles). Bony union was observed in 89.5% of cases (60/67). In all, nine patients (13.4%) needed a secondary surgery: three for talonavicular nonunion, four for progression of the flatfoot deformity, and two for screw protrusion. No cases of superficial infection, wound dehiscence, or avascular necrosis of the talus were observed.

CONCLUSION

The present series represents the largest study of stage III flatfoot correction using MIS with a mid- to long-term follow-up. Because the data showed clinical and functional improvement after surgery with fewer complications, this technique may be ideal for patients at risk of complications. Graphical abstract.

Comparative Study of Spring Ligament Reconstructions Using Either Hamstring Allograft or Synthetic Ligament Augmentation

BACKGROUND

Idiopathic flatfeet are usually caused by attenuation of the medial soft tissues rather than a lateral osseous deficiency. Debate continues on whether spring ligament attenuation or posterior tibial tendon (PTT) dysfunction is the initial driver for the deformity. Our comparative prospective study aimed to quantify the radiological and clinical outcomes of 2 techniques for spring ligament reconstruction using a hamstring graft or a synthetic ligament.

METHODS

Seventeen spring ligament reconstructions (SLRs) were performed in 17 patients using synthetic ligament augmentation and 16 SLRs were performed using hamstring allograft in 13 patients. Additional procedures such as gastrocnemius recession, PTT advancement, flexor digitorum longus transfer, and calcaneal osteotomy were performed as required. A minimum of 12 months of follow-up was available for all cases. Radiographic analysis was performed with standardized parameters.

RESULTS

Following SLR with synthetic ligament augmentation, all radiological parameters significantly improved (P < .05). Hamstring allograft SLR also demonstrated significantly improved radiographic parameters in all but Meary's line at final follow-up. At 12 months, patient outcome scores were significantly better in the synthetic ligament group.

CONCLUSION

Reconstruction of the spring ligament using either hamstring allograft or synthetic ligament augmentation provided significant improvements in radiological alignment; however, superior patient-reported outcomes were found in the synthetic ligament augmentation group.

LEVELS OF EVIDENCE

Level III, retrospective cohort study.

Combined Subtalar and Naviculocuneiform Fusion for Treating Adult Acquired Flatfoot Deformity With Medial Arch Collapse at the Level of the Naviculocuneiform Joint

BACKGROUND:

A challenge in treating acquired flatfoot deformities is the collapse of the medial arch at the level of the naviculocuneiform (NC) joint. Triple fusions, being a treatment option, may lead to problems such as increased foot stiffness. We thus established a method that combines subtalar (ST) fusion with NC fusion while preserving the Chopart joint. We analyzed the radiographic correction, fusion rate, and patient satisfaction with this procedure.

METHODS:

34 feet in 31 patients (female, 23; male, 8; age 67 [45-81] years) were treated with a ST and NC joint fusion. In 15 cases, a medial sliding-osteotomy was additionally necessary to fully correct hindfoot valgus. The following radiographic parameters were measured on weightbearing radiographs preoperatively and at 2 years: talo-first metatarsal angle, talocalcaneal angle, calcaneal pitch, talonavicular coverage angle and calcaneal offset. Fusion was radiologically confirmed.

RESULTS:

All parameters, except the calcaneal pitch, showed a significant improvement. Fusion was observed after 1 year in all but 2 cases (94.1%). One nonunion each occurred at the ST and NC joint without needing any subsequent treatment. One patient developed avascular necrosis of the lateral talus with need for total ankle replacement after 1 year. All patients were satisfied with the obtained results.

CONCLUSION:

Our data suggest that a combined fusion of the ST and NC joint was effective and safe when treating adult acquired flatfoot with collapse of the medial arch at the level of the NC joint. Although the talonavicular joint was not fused, its subluxation was significantly reduced.

LEVEL OF EVIDENCE:

Level IV, case series.

Outcomes of Reconstruction of the Stage II Adult-Acquired Flatfoot Deformity in Older Patients

BACKGROUND

Reconstruction of the stage II adult-acquired flatfoot deformity (AAFD) often requires the use of multiple osteotomies and soft tissue procedures that may not heal well in older patients. The purpose of our study was to determine whether patients older than 65 years with stage II AAFD had inferior clinical outcomes or an increased number of subsequent surgical procedures after flatfoot reconstruction when compared with younger patients.

METHODS

One-hundred forty consecutive feet (70 right, 70 left) with stage II AAFD in 137 patients were divided into 3 groups based on age: younger than 45 years (young; n = 21), 45 to 65 years (middle-aged; n = 87), and 65 years and older (older; n = 32). Preoperative and postoperative Foot and Ankle Outcome Scores (FAOSs) at a minimum of 2 years were compared. Hospital records were reviewed to determine if patients underwent a subsequent procedure postoperatively.

RESULTS

Patients in the older group did not demonstrate any differences in changes in FAOS subscales compared with patients in the young and middle-aged groups (all P > .15). The older group had significant preoperative to postoperative improvements in all the FAOS subgroups ( P < .01). In addition, patients in the older group were not more likely to undergo a subsequent surgery than were the younger patients (all P > .10).

CONCLUSIONS

Our study found that patients older than 65 years with stage II AAFD have improvements in patient-reported outcomes and rates of revision surgery after surgical reconstruction that were not significantly different than those of younger patients.

LEVEL OF EVIDENCE

Therapeutic Level III, comparative series.

Severe Stage 2: Fuse or Reconstruct

Stage II posterior tibial tendon dysfunction encompasses a wide range of patients with varying degrees of deformity and function. The spectrum of patients can be difficult to treat with a single surgical approach, as evidenced by the wide range of techniques present in the literature. Severity of the deformity, patient functional level, age, and comorbidities must be considered to determine the best course of treatment. This article examines when fusion versus reconstruction is the appropriate treatment of patients with severe stage II posterior tibial tendon dysfunction and its subclassifications.

Hindfoot Arthrodesis for the Elective and Posttraumatic Foot Deformity

Triple (talonavicular, subtalar, and calcaneocuboid) joint arthrodesis and most recently double (talonavicular and subtalar) joint arthrodesis have been well proposed in the literature for surgical repair of the elective, posttraumatic, and/or neuropathic hindfoot deformities. The articulation of the hindfoot with the ankle and midfoot is multiaxial, and arthrodesis of these joints can significantly alter the lower extremity biomechanical manifestations by providing anatomic correction and alignment. This article reviews the indications and preoperative planning for some of the most common procedures to address the hindfoot deformity.

Adult-acquired flatfoot deformity

Adult-acquired flatfoot deformity (AAFD) is a known and recognized cause of pain and disability. Loss of PTT function is the most important contributor to AAFD, and its estimated prevalence is thought to be over 3%. This review aims to summarize the current literature and encompass recent advances regarding AAFD.

Clinical Outcomes of Nonunions of Hindfoot and Ankle Fusions

BACKGROUND

While nonunion after foot and ankle fusion surgery has been associated with poor outcomes, we are not aware of any longitudinal study on this subject. Thus, we prospectively evaluated the impact of nonunion on clinical outcomes of foot and ankle fusions and identified potential risk factors for nonunion after these procedures.

METHODS

Using data from a randomized clinical trial on recombinant human platelet-derived growth factor-BB (rhPDGF-BB; Augment Bone Graft, BioMimetic Therapeutics), union was defined either by assessment of computed tomography (CT) scans at 24 weeks by a reviewer blinded to the type of treatment or by the surgeon's composite assessment of clinical and radiographic findings at 52 weeks and CT findings at 24 or 36 weeks. The nonunion and union groups (defined with each assessment) were then compared in terms of clinical outcome scores on the American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Scale (AOFAS-AHS), Foot Function Index (FFI), and Short Form-12 (SF-12) as well as age, sex, body mass index (BMI), smoking status, diabetes status, work status, and arthrodesis site.

RESULTS

Blinded CT assessment identified nonunion in 67 (18%) of 370 patients, and surgeon assessment found nonunion in 21 (5%) of 389 patients. Postoperatively, the nonunion group scored worse than the union group, regardless of the method used to define the nonunion, on the AOFAS-AHS and FFI, with mean differences of 10 and 12 points, respectively, when nonunion was determined by blinded CT assessment and 19 and 20 points when it was assessed by the surgeon. The nonunion group also had worse SF-12 Physical Component Summary scores. Differences between the union and nonunion groups were clinically meaningful for all outcome measures, regardless of the nonunion assessment method. The concept of an asymptomatic nonunion (i.e., imaging indicating nonunion but the patient doing well) was not supported. Patients with nonunion were more likely to be overweight, smokers, and not working.

CONCLUSIONS

This prospective longitudinal study demonstrated poorer functional outcomes in patients with a nonunion after foot and ankle fusion, regardless of whether the diagnosis of nonunion was based on CT only or on combined clinical, radiographic, and CT assessment.

LEVEL OF EVIDENCE

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

Injectable Recombinant Human Platelet-derived Growth Factor in Collagen Carrier for Hindfoot Fusion

Arthrodesis of the hindfoot is a common procedure for degenerative joint disease and/or severe deformity. Nonunion is a common complication from this procedure, causing an increased burden to the patient and health care system, often resulting in the need for revision surgery. Recombinant human platelet-derived growth factor (rhPDGF) has been shown to be a safe and effective tool to enhance arthrodesis rates in hindfoot surgery while avoiding the potential morbidity of bone grafting. This article provides a review of the role of rhPDGF in hindfoot fusions, and the surgical technique for performing an rhPDGF enhanced double-arthrodesis through a medial approach.

The Importance of Sufficient Graft Material in Achieving Foot or Ankle Fusion

BACKGROUND

Nonunion, an important complication following foot and ankle arthrodesis, causes substantial morbidity and disability. In patients undergoing hindfoot and ankle arthrodesis, autogenous bone graft (autograft) or a suitable alternative is often used to promote osseous fusion across the joint. This study assessed the importance of adequate graft material in the fusion space to achieve joint fusion during ankle and hindfoot arthrodesis.

METHODS

This study used data from a previously published clinical trial of grafting material (recombinant human platelet-derived growth factor-BB with beta-tricalcium phosphate [rhPDGF-BB/β-TCP] or autograft) for healing in hindfoot and ankle arthrodesis to correlate the amount of graft fill at 9 weeks with ultimate healing. Patients who received supplemental graft material for ankle or hindfoot arthrodesis for end-stage ankle or hindfoot arthritis were stratified according to nonunion risk factors and surgical fusion site. Patients underwent arthrodesis using standard rigid internal fixation. Graft fill was defined as "adequate" if the material occupied ≥50% of the cross-sectional area of the fusion space on a computed tomography (CT) scan made at 9 weeks. Fusion was defined as osseous bridging of ≥50% of each articulation on a CT scan made at 24 weeks. Three hundred and seventy-nine patients with 573 joints (383 managed with rhPDGF-BB/β-TCP and 190 managed with autograft) that underwent arthrodesis had complete follow-up with 9-week and 24-week CT scans available.

RESULTS

Overall, 472 (82%) of 573 joints had adequate graft fill; of those, 383 (81%) were successfully fused at 24 weeks compared with 21 (21%) of 101 joints without adequate graft fill (p < 0.0001). Absolute fusion rate differences (joints with adequate fill minus those without adequate fill) were consistent across joints (61% to 63%) and for graft materials. The overall odds ratio (OR) of successful fusion in joints with adequate graft fill compared with those without adequate graft fill was 16.4 (95% confidence interval, 9.6 to 27.9).

CONCLUSIONS

This study demonstrates an association between the amount of graft material and successful hindfoot and ankle arthrodesis. Graft material filling of ≥50% of the fusion space at 9 weeks, regardless of type or origin, was associated with significantly higher fusion rates at 24 weeks.

LEVEL OF EVIDENCE

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