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

Naviculocuneiform joint arthrodesis in a cohort of 36 patients

BACKGROUND

Arthrodesis of the naviculocuneiform joint (NCJ) can be performed in isolation or in conjunction with arthrodesis of other joints, often in the presence of deformity. In the literature there is relative rarity of articles reporting on results and complications of NCJ arthrodesis.

PATIENTS AND METHODS

Thirty-six patients (36 feet) with symptomatic NCJ arthritis underwent arthrodesis. Mean age was 59.1 years (SD 13.1; range 26-78) and 24 were women. Adjuvant procedures were performed simultaneously in 29 patients, whilst 17 had planovalgus and 1 had cavovarus foot deformity.

RESULTS

Union of the NCJ arthrodesis was achieved in 35 out of 36 (97.2 %) patients, whilst one patient developed non-union. Mean time to union was 13.1 weeks (SD 3.8; range 8-24). Two patients (5.6 %) developed deep infection and 5 patients (13.9 %) required secondary surgical procedures. Twenty-three patients (63.9 %) rated the outcome as good or excellent, 11 (30.6 %) as fair and 2 (5.6 %) as poor.

CONCLUSIONS

NCJ arthrodesis was part of a more complex procedure in most of the patients. Whilst union was achieved in almost all patients and complication rate was acceptable, only 64 % rated their outcome as good or excellent.

LEVEL OF CLINICAL EVIDENCE

IV.

The Navicular Cuneiform Joint: Updates on Avoiding and Managing a Nonunion

Naviculocuneiform arthrodesis, while often used to support the medial column during management of primary/post-traumatic arthritis, deformity correction, or in the surgical treatment of progressive collapsing foot deformity, can develop nonunion. Addressing this condition hinges on the assessment of various parameters such as patient/host factors and recognition of the etiology of the nonunion. In this article, methods of optimizing this surgical intervention through anatomic and physiologic considerations are highlighted. Further, information is provided to assist foot and ankle surgeons in performing a comprehensive work-up to allow for successful reconstruction and optimal patient outcomes.

Addressing Medial Column Instability in Flatfoot Deformity

A stable medial column is important to the normal function of the foot and ankle. Medial column instability and forefoot varus can result in compensatory hindfoot motion leading to stress along the medial soft-tissue structures. Medial column stabilization should therefore be considered when (1) forefoot varus deformity is identified following hindfoot realignment; (2) pronounced medial column instability is present, even in the absence of forefoot varus; and (3) when degenerative changes are present within the medial column articulations. Common surgical procedures include arthrodesis of the talonavicular joint, naviculocuneiform joint, and first tarsometatarsal joint, as well as osteotomy of the medial cuneiform (Cotton osteotomy).

Naviculocuneiform Arthrodesis for Treatment of Adult-Acquired Flatfoot Deformity

The adult-acquired flatfoot is a complex multiplanar deformity that requires the foot and ankle surgeon to balance soft tissue, correct hindfoot valgus, and address instability of the medial column. The naviculocuneiform joint is historically underappreciated in regard to its involvement in medial column instability relative to the talonavicular and tarsometatarsal joints. Proper clinical and radiographic evaluation of the medial column, specifically evaluating for deformity at each medial column joint, will allow the surgeon to ensure correction of deformity and decrease the recurrence of instability or failure of the reconstruction.

Correction of a Complex Foot Deformity With V and Y Osteotomy and Ilizarov Method

Many authors consider the Ilizarov method as the best choice for correction of complex multiplanar foot deformities. Fifty-one patients, for a total of 55 feet, underwent V or Y osteotomy (respectively 32 and 23), 12 were due to congenital clubfoot outcomes, 11 were from post-traumatic pathologies, 9 from hemimelia, 7 from Charcot-Marie-Tooth, 5 from poliomyelitis, 3 from spina bifida, 2 from myopathy, 2 from poly-epiphyseal dysplasia, 1 from achondroplasia, 1 from arthrogryposis, 1 patient from Charcot's foot and 1 rheumatoid arthritis. All patients were contacted to undergo AOFAS and EQ-5D-5L questionnaire. The mean distraction time was 74.0 days (±25.3) and it was longer for V osteotomy (63.1 ± 21.1 vs 81.8 ± 25.4 days for Y and V respectively, p = .006). The average fixation time was 97.9 days (± 61.2), 90 days in the Y and 103 days in the V osteotomy groups. The mean preoperative foot length was longer in the group of Y osteotomy patients (158.7 ± 21.3 mm vs 133.5 ± 21.6 mm, p < .001). The mean length postoperatively was substantially the same (Y group 164.0 mm vs V group 167.4 mm, p < .562). The V osteotomy produces an elongation ratio of 440% with respect to that produced from the Y osteotomy (ratio length/distraction V/Y 0.44/0.1), with only 19% more in the distraction days. (81.8 V group vs 63.1 Y group). While the V osteotomy allows a lengthening of about 27%, the Y osteotomy, despite having correction potential superimposable to the V osteotomy, minimizes the elongation component.

Managing Complications of Foot and Ankle Surgery: Reconstruction of the Progressive Collapsing Foot Deformity

Our understanding of the cause and principles of treatment of progressive collapsing foot deformity (PCFD) has significantly evolved in recent decades. The goals of treatment remain improvement in symptoms, correction of deformity, maintenance of joint motion, and return of function. Although notable advancements in understanding the deformity have been made, complications still occur and typically result from (1) poor decision making, (2) technical errors, and (3) patient-related conditions. In this article, we discuss common surgical modalities used in the treatment of PCFD and further highlight the common complications that occur and the techniques that can be used to prevent them.

Subtalar Fusion for Correction of Forefoot Abduction in Stage II Adult-Acquired Flatfoot Deformity

BACKGROUND

Correction of talonavicular uncoverage (TNU) in adult-acquired flatfoot deformities (AAFD) can be a challenge. Lateral column lengthening (LCL) traditionally is utilized to address this. The primary study objective is examining stage II AAFD patients and determining if correction can be achieved with subtalar fusion (STF) comparable to LCL.

METHODS

Following institutional review board approval, retrospective chart review performed identifying patients meeting criteria for stage IIB AAFD who underwent either STF with concomitant flatfoot procedures (but not LCL) to correct TNU, or who underwent LCL as part of their flatfoot reconstruction. Patients indicated for STF had one or more of the following: higher body mass index (BMI), were older, had greater deformity, lateral impingement pain, intraoperative spring ligament hyperlaxity. Patients without 1-year follow-up or compete records were excluded. All other patients were included. A total of 27 isolated STFs identified, along with 143 who underwent LCL. Pre-/postoperative radiographic parameters obtained as well as PROMIS (Patient-Reported Outcomes Measurement Information System) and FAOS (Foot and Ankle Outcome Score) scores. Radiographic and patient reported outcomes both preoperatively and at 1-year follow-up evaluated for both groups.

RESULTS

STF patients were older (P < .05), with higher BMIs (P < .004). STF had significantly worse TNU (P < .001) than LCL patients, and average change in STF TNU was larger than LCL change postoperatively (P = .006), after adjusting for age, BMI, gender. PROMIS STF improvement reached statistical significance in Physical Function (P 0.011), for FAOS Pain (P 0.025) and Function (P = 0.04).

CONCLUSIONS

STF can be used in appropriately indicated patients to correct flatfoot deformity without compromising radiographic or clinical, correcting not only hindfoot valgus, but also talonavicular uncoverage (TNU) and corresponding medial arch collapse.

LEVELS OF EVIDENCE

Level III: Retrospective chart review comparison study (case control).

Deformity Correction of the Midfoot/Hindfoot/Ankle

The correction of the deformed arthritic foot and ankle is a complicated and somewhat controversial topic. After conservative methods fail, there is a wide range of possible bony procedures and arthrodesis that maybe performed. The appropriate work up and understanding of the pathomechanics is vital to the correct choice of procedures to correct these deformities. Once the work up and procedure selection is done, the operation must also be technically performed well and with efficiency, as most often the condition is corrected with a variety of procedures. This article discusses some of the most common procedures necessary to fully correct deformity of the midfoot, hindfoot, and ankle. This article will also discuss the authors' technique and pearls.

Assessment of Progressive Collapsing Foot Deformity Using Semiautomated 3D Measurements Derived From Weightbearing CT Scans

BACKGROUND

In progressive collapsing foot deformity (PCFD), hind- and midfoot deformities can be hard to characterize based on weightbearing plain radiography. Semiautomated 3-dimensional (3D) measurements derived from weightbearing computed tomography (WBCT) scans may provide a more accurate deformity assessment. In the present study, automated 3D measurements based on WBCT were used to compare hindfoot alignment of healthy individuals to patients with PCFD.

METHODS

The WBCT scans of 20 patients treated at our institution with either a flexible (N = 10) or rigid (N = 10) PCFD were compared with the WBCT scans of a control group of 30 healthy individuals. Using semiautomated image analysis software, from each set of 3D voxel images, we measured the talar tilt (TT), hindfoot moment arm (HMA), talocalcaneal angle (TCA; axial/lateral), talonavicular coverage (TNC), and talocalcaneal overlap (TCO). The presence of medial facet subluxation as well as sinus tarsi/subfibular impingement was additionally assessed.

RESULTS

With the exception of the TCA (axial/lateral), the analyzed measurements differed between healthy individuals and patients with PCFD. The TCA axial correlated with the TNC in patients with PCFD. An increased TCO combined with sinus tarsi impingement raised the probability of predicting a deformity as rigid.

CONCLUSION

Using 3D measurements, in this relatively small cohort of patients, we identified relevant variables associated with a clinical presentation of flexible or rigid PCFD. An increased TCO combined with sinus tarsi impingement raised the probability of predicting a deformity as rigid. Such WBCT-based markers possibly can help the surgeon in decision-making regarding the appropriate surgical strategy (eg, osteotomies vs realignment arthrodesis). However, prospective studies are necessary to confirm the utility of the proposed parameters in the treatment of PCFD.

LEVEL OF EVIDENCE

Level III, case-control study.

Joint Preservation Surgery for Varus and Posterior Ankle Arthritis Associated with Flatfoot Deformity

This article introduces novel types of ankle arthritis related to a flatfoot deformity. There has been a long-held belief that severe unmanaged flatfoot deformity leads to valgus ankle arthritis, due to deltoid ligament insufficiency. However, flatfoot deformity can also give rise to varus ankle arthritis as the talus and calcaneus subluxate into opposite directions. Plantarflexion and posterior translation of the talus in the sagittal plane contributes to the eccentric narrowing of the posterior aspect of the tibiotalar joint, which the authors termed posterior ankle arthritis. Subtalar arthrodesis was performed to address the opposing dynamics of the talus and calcaneus, and was combined with a medial longitudinal arch reconstruction in most cases of posterior ankle arthritis and in selected cases of varus ankle arthritis, and satisfactory clinical and radiological results were achieved.

Repositional Subtalar Arthrodesis Combined With Supramalleolar Osteotomy for Late-Stage Varus Ankle Arthritis With Hindfoot Valgus

BACKGROUND

Late-stage varus ankle arthritis is thought to be associated with varus of the tibial plafond and hindfoot. However, some late-stage varus arthritis show hindfoot valgus, which can be explained by subtalar subluxation with opposite directional motion between the talus and calcaneus. We hypothesized that late-stage varus ankle arthritis with hindfoot valgus could improve with repositional subtalar arthrodesis and supramalleolar osteotomy (SMO). The purpose of this study was to investigate the clinical and radiographic results of the repositional subtalar arthrodesis combined with SMO for late-stage varus ankle arthritis with hindfoot valgus.

METHODS

This study includes 16 consecutive patients (16 ankles) with late-stage varus ankle arthritis of Takakura stage 3-b and hindfoot valgus who were treated using repositional subtalar arthrodesis combined with SMO and followed for a minimum of 2 years. Clinical results were assessed with the visual analog scale (VAS) and the Foot Function Index (FFI). Radiographic results were assessed with standard parameters measured on weightbearing foot and ankle radiographs. Clinical and radiographic results were evaluated preoperatively and at the last follow-up.

RESULTS

VAS and FFI significantly improved after surgery. Mean talar tilt angle improved from 12.8 ± 2.8 degrees to 3.9 ± 3.1 degrees (P < .001). Talus center migration and Meary angle significantly improved after surgery. Medial distal tibial angle, lateral talocalcaneal angle, hindfoot moment arm, and talonavicular coverage angle significantly changed after surgery. Radiographic stage improved in 15 ankles (93.8%) after surgery.

CONCLUSION

In this series with minimum 2-year follow-up, we found that late-stage (Takakura stage 3-b) varus ankle arthritis with hindfoot valgus clinically and radiographically improved with repositional subtalar arthrodesis combined with SMO.

LEVEL OF EVIDENCE

Level IV, prognostic.

Plantar Plating for Medial Naviculocuneiform Arthrodesis in Progressive Collapsing Foot Deformity

Background:

Medial column procedures are commonly used to treat progressive collapsing foot deformity (PCFD) reconstruction. The aim of this research is to present the clinical results of plantar plating for medial naviculocuneiform (NC) arthrodesis when NC joint pathology contributes to medial arch collapse. The authors hypothesized that lag screws with a plantar neutralization plate would result in a satisfactory NC joint fusion rate.

Methods:

A single-surgeon, retrospective case series was performed on patients with flexible PCFD who underwent NC arthrodesis using lag screws and a contoured neutralization plate applied plantarly across the medial NC joint as part of PCFD reconstruction. Thirteen patients (11 females, 2 males; mean age 53.1 [34-62] years) between 2016 and 2019 were identified for inclusion. Mean follow-up was 25.2 ± 12.7 months. Preoperative and postoperative anteroposterior talo–first metatarsal angle, lateral talo–first metatarsal angle, talonavicular coverage angle, and calcaneal pitch were measured. Union was evaluated radiologically. AOFAS midfoot scores were recorded at final follow-up.

Results:

All parameters demonstrated a significant improvement. Fusion was confirmed in 11 of 13 patients (85%) at a mean 5.7 ± 2.1 months. One patient required a revision of their NC fusion because of symptomatic nonunion. There were no cases of symptomatic plantar hardware.

Conclusion:

The results of this small cohort series suggest that lag screw with plantar plate NC arthrodesis yielded generally improved short-term radiographic and clinical outcomes in PCFD patients with medial arch collapse through the NC joint.

Level of Evidence: Level IV, retrospective case series.

Talus morphology differs between flatfeet and controls, but its variety has no influence on extent of surgical deformity correction

BACKGROUND

Progressive collapsing foot deformity (PCFD) is a complex 3-dimensional (3-D) deformity with varying degrees of hindfoot valgus, forefoot abduction, and midfoot varus. The first aim of this study was to perform a 3-D analysis of the talus morphology between symptomatic PCFD patients that underwent operative flatfoot correction and controls. The second aim was to investigate if there is an impact of individual talus morphology on the success of operative flatfoot correction.

METHODS

We reviewed all patients that underwent lateral calcaneal lengthening for correction of PCFD between 2008 and 2018 at our clinic. Radiographic flatfoot parameters on preoperative and postoperative radiographs were assessed. Additionally, 3-D surface models of the tali were generated using computed tomography (CT) data. The talus morphology of 44 flatfeet was compared to 3-D models of 50 controls without foot or ankle pain of any kind.

RESULTS

Groups were comparable regarding demographics. Talus morphology differed significantly between PCFD and controls in multiple aspects. There was a 2.6° increased plantar flexion (22.3° versus 26°; p = 0.02) and medial deviation (31.7° and 33.5°; p = 0.04) of the talar head in relation to the body in PCFD patients compared to controls. Moreover, PCFD were characterized by an increased valgus (difference of 4.6°; p = 0.01) alignment of the subtalar joint. Satisfactory correction was achieved in all cases, with an improvement of the talometatarsal-angle and the talonavicular uncoverage angle of 5.6° ± 9.7 (p = 0.02) and 9.9° ± 16.3 (p = 0.001), respectively. No statistically significant correlation was found between talus morphology and the correction achieved or loss of correction one year postoperatively.

CONCLUSION

The different morphological features mentioned above might be contributing or risk factors for progression to PCFD. However, despite the variety of talar morphology, which is different compared to controls, the surgical outcome of calcaneal lengthening osteotomy was not affected.

LEVEL OF EVIDENCE

III.

Adult Acquired Flatfoot Deformity

Adult acquired flatfoot deformity (AAFD) is a condition commonly seen by orthopaedic surgeons. Posterior tibial tendon dysfunction is thought to be the initial pathoanatomic etiology that leads to this deformity. Successful resolution of the pain associated with AAFD can be achievable with nonsurgical methods. Patients who continue to have pain or functional limitations despite nonsurgical treatment can find improvement with appropriately selected surgical interventions. This article addresses new advances in treatment based on the stage of AAFD and will identify areas of continued development with a focus on surgical management. The literature continues to evolve as demonstrated by a recent update regarding the nomenclature and treatment of this condition to progressive collapsing flatfoot deformity. Future goals of research include understanding the natural history of the disease, from asymptomatic to symptomatic, and studying a wide array of newer treatments and implants that have not been prospectively evaluated.

Biomechanical evaluation of naviculocuneiform fixation with lag screw and locking plates

BACKGROUND

There have been no biomechanical evaluations of naviculocuneiform (NC) joint fixation. This study compared biomechanically 3 different fixation constructs for NC-1-3 joint fixation.

METHODS

The present study compared the three fixation constructs lag screw with locking plate for each NC joint, two crossed lag screws for each NC joint and a separate lag screw for each NC joint with bridging locking plates. NC-1-3 fixation was performed stepwise, and rotation of each joint was evaluated after the application of each lag screw or locking plate and their removal.

RESULTS

All examined fixation techniques led to a significant reduced rotation of the NC joints. For NC-1 rotation decreased from 2.8° (Range 1.2-6.6°) to 0.6° (0.2-3.0°) for lag screw and locking plate (p = 0.002) and from 5.0° (1.7-9.8°) to 1.0° (0.1-3.6°) for crossed lag screws (p = 0.002). For NC-2, locking plate constructs were better with 0.2° (0.1-0.5°) compared to crossed lag screw osteosynthesis with 0.9° (0.2-1.6°) (p = 0.011).

CONCLUSION

Each evaluated fixation technique led to a reduced NC joint rotation. The fixation of any NC joint had no relevant effect on the adjacent NC joints. The results might support surgeons treating NC joint disorders.

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.

Deep Peroneal Neurectomy for Midfoot Arthritis

Osteoarthrosis of the tarsometatarsal joint (TMTJ) and naviculocuneiform joint (NCJ) is a common pathology treated by foot and ankle specialists. Arthrodesis is the most widely accepted surgical treatment. Patients that are not candidates for arthrodesis are often left without surgical treatment options. Neurectomy has been described for treatment of upper extremity joint arthrosis but has not been well described in the foot. The deep peroneal nerve innervates the first, second, third TMTJs and NCJ. We present a retrospective case series on the outcomes of patients treated with deep peroneal neurectomy for TMTJ and NCJ arthrosis (N = 34 feet in 26 patients). The median postoperative American Orthopedic Foot and Ankle Society midfoot score was 53 (range 16-75) points. Twenty two (85%) of 26 patients stated that their expectations were met as a result of the deep peroneal neurectomy procedure, and 20 (77%) of 26 patients stated that they would have deep peroneal neurectomy for their symptoms again. There were recurrent symptoms prompting patients to seek additional treatment in 7 (21%) of 34 feet. Recurrent pain is also documented in hand denervation studies and the physiologic explanation remains unclear. Our results suggest that deep peroneal neurectomy is an effective treatment option for TMTJ and NCJ arthritis and may be particularly helpful in patients that are poor candidates for arthrodesis.

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.

The Failed Deltoid Ligament in the Valgus Misaligned Ankle-How to Treat?

This article deals with the treatment of a chronically failed deltoid ligament complex in the valgus misaligned ankle. This is a challenging task in every orthopedic foot and ankle surgery. Before embarking on any surgery that relates to the deltoid ligament complex, it is mandatory to analyze any underlying cause that could promote the impairment. Once this is done, it might be of value in considering anatomic reconstructions. The article provides an anatomic reconstruction technique, which should help address the problem.

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.

[Surgical procedures for the correction and stabilization of pes planovalgus]

The medial column of the foot is a relevant factor of the pathogenesis of pes planovalgus. Crucial anatomic structures are the tibiocalcaneonavicular ligament complex, the naviculocuneiform joints, including the ossa cuneiformia, and the first tarsometatarsal joint. A combination of bony and soft tissue reconstructive techniques must, therefore, be taken into account when treating pes planovalgus. The present article presents stabilizing and correcting surgical procedures for the medial column of the foot, including basic anatomy and biomechanics.

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.

Contribution of First-Tarsometatarsal Joint Fusion to Deformity Correction in the Treatment of Adult-Acquired Flatfoot Deformity

Background:

Severe adult-acquired flatfoot deformity (AAFD) is often associated with painful medial column collapse at the naviculocuneiform (NC) joint. However, many surgeons surgically correct the deformity without directly addressing this joint. The purpose of this study was to examine the role of first-tarsometatarsal (TMT) fusion combined with subtalar fusion in correcting deformity at the NC joint.

Methods:

We retrospectively analyzed 40 patients (41 feet) who underwent first-TMT and subtalar (ST) fusion as part of a flatfoot reconstructive procedure. We assessed 6 radiographic parameters both preoperatively and at a minimum of 6 months postoperatively, including talonavicular (TN) coverage angle, lateral talo–first metatarsal angle, lateral talocalcaneal angle, calcaneal pitch, hindfoot moment arm, and a newly defined navicular-cuneiform incongruency angle (NCIA). Patient-Reported Outcomes Measurement Information System (PROMIS) clinical outcomes were assessed preoperatively and at a minimum 1-year follow-up.

Results:

The NCIA demonstrated excellent interobserver reliability, with no significant change between pre- and postoperative measurements. All other radiographic parameters, except calcaneal pitch, demonstrated statistically significant improvement postoperatively (P < .01). Overall, patients had statistically significant improvement in all PROMIS domains (P < .01), except for depression. Worsening NC deformity was not associated with worse patient-reported outcomes.

Conclusions:

Our data suggest that when addressing painful collapse of the medial arch in patients with AAFD, fusion of the first-TMT joint in combination with other procedures leads to acceptable radiographic and clinical outcomes. There was no change in deformity at the NC joint in our patient cohort at short-term follow-up, and patients achieved significant improvement in multiple PROMIS domains. Although TMT fusion had no effect on NC deformity, residual or worsening NC deformity did not significantly affect clinical outcomes. In addition, the NCIA was found to be a reliable radiographic parameter to assess NC deformity in the presence of talonavicular and/or first-TMT fusion.

Level of Evidence:

Level III, retrospective comparative study.

Post-Traumatic Hindfoot Arthritis

The hindfoot is functionally defined as the articulations between the talus, calcaneus, navicular, and cuboid. It is a biomechanically important peritalar unit for shock absorption and propulsion with the subtalar and talonavicular joint essential to its function. The primary cause of hindfoot arthritis is post-traumatic. Other causes include long-term misalignment such as adult-acquired flatfoot, cavus foot, and inflammatory arthritis. Prevention of post-traumatic hindfoot arthritis is the primary objective. Anatomical reduction and fixation of articular hindfoot fractures is the preferred pathway. This article discusses the principles of treatment of hindfoot arthritis. When post-traumatic changes cannot be managed by nonsurgical means, an anatomical well-aligned arthrodesis is indicated. This article addresses the principles of managing this condition, which have been championed by Professor Sigvard T. Hansen. New approaches and techniques are discussed that achieve the goals of a stable, functional plantigrade foot.