Vascularity evaluation of the equine tarsocrural and proximal intertarsal joint septum, and comparative analysis of two arthroscopic transection techniques.

OBJECTIVE: To evaluate vascularity of the synovial membrane covered septum (SMS) separating the tarsocrural (TC) and proximal intertarsal (PIT) joints (Part 1) and compare two methods of transection, electrosurgical or Ferris Smith rongeur (FS rongeur) (Part 2). STUDY DESIGN: Experimental study. SAMPLE POPULATION: Part 1, 10 SMS (n = 5 horses). Part 2, six horses (n = 12 tarsi). METHODS: In part 1, SMS harvested postmortem were each divided into eight regions of interest (ROIs), processed for histology, and immunostained with anti-α-actin antibody for blood vessel identification. Vascular density was calculated for each ROI. Data was compared within and between horses. In part 2, six horses underwent TC arthroscopy. Each limb was randomly assigned to undergo either electrosurgical or FS rongeur SMS transection. SMS transection and total operative time were recorded. Intraoperative hemorrhage was scored. Data was compared between both techniques. RESULTS: Significant interindividual variations in SMS vascular density were detected (p = .02), but there were no differences among ROIs. No differences in the transection time were detected between electrosurgery (4.83 ± 0.54 min) and FS rongeur (4.33 ± 0.67 min). No differences were found in intraoperative hemorrhage scores between techniques. CONCLUSION: Vascularity within the SMS varies among horses but not within its regions. Electrosurgical or FS rongeur transection of the medial SMS during tarsocrural arthroscopy is a rapid technique and improves surgical access to the dorsal compartment of the PIT.

Outcomes of Selective Arthrodesis Based on Joints Affected in 33 Feet With Müller-Weiss Disease.

No consensus exists regarding operative treatment of Müller-Weiss disease (MWD). Its only classification is based solely on Méary's angle and serves neither as guide to management nor prognosis. We report on 33 feet that underwent surgery following failed conservative management. Treatment was directed towards joint(s) involved, as determined by clinical examination, plain radiography and SPECT-CT. Thus, surgery consisted of isolated talonavicular in 6 feet, triple in 8, subtalar and talonavicular in 7, talonaviculocuneiform in 4, talonaviculocuneiform with interpositional tricortical iliac crest graft in 6 and pantalar arthrodesis in 2. PROMIS scores for pain interference and depression decreased significantly (p < .001) with significant accompanying increase in physical function (p = .003). Union occurred in 31 of 33 feet (94%) with complete resolution of pain at an average follow-up of 84 months. Of the 2 nonunions, 1 had fracture through the lateral navicular, and the other marked sclerosis and avascularity of the lateral navicular. We describe our pathways for selecting arthrodesis based on the joints affected. Isolated talonavicular arthrodesis was performed in early stages of MWD, which begins at the talonavicular articulation. When disease extended to both sides of the navicular, we performed talonaviculocuneiform arthrodesis. When considering isolated talonavicular, double medial or triple arthrodesis, there should be adequate cancellous bone stock remaining in the lateral part of the navicular, as determined on medial oblique radiographs and CT scan. In case of inadequate bone stock or fracture through the lateral navicular, talonaviculocuneiform arthrodesis with interpositional iliac crest bone graft is recommended.

Nonunion Rate Following Primary Arthrodesis for Acute Lisfranc Injuries.

Injury to the tarsometatarsal joint (TMT) results in instability throughout the midfoot that does not often improve with conservative management. If instability is identified, surgical intervention is frequently recommended, either open reduction and internal fixation (ORIF) or primary arthrodesis (PA). These 2 treatment options have been compared in the literature multiple times, often reporting similar outcomes. Due to this, as well as the need for subsequent hardware removal after ORIF has led many surgeons towards PA at the index surgery. Concern for nonunion is a leading concern with surgeons who advocate instead for ORIF. The purpose of this study is to review patients who underwent PA and observe nonunion rates. Nonunion at the TMT has been previously studied, but only in the chronic setting. We performed a retrospective study of 34 patients who had PA in the management of an acute Lisfranc injury. The average age in our study was 43.9 years old (range 19-72, SD 17.4) with an average follow-up of 9.4 months (range 4-33, SD 6.2). Radiographs were evaluated for signs of nonunion at regular postoperative intervals. Within the patients included in the study, a total of 71 TMT joints were fused. Overall successful fusion rate was 95.8% at an average of 7.9 weeks (range 6-12, SD 1.4) postoperatively. Individual nonunion rates at the first, second, and third TMT were 0%, 1.4% and 2.8% respectively. Our study demonstrates that primary arthrodesis provides a predictable outcome with low nonunion rates in the management of acute Lisfranc injury.

Talonavicular-cuneiform arthrodesis in the management of Mueller-Weiss Syndrome: a retrospective case series.

Mueller-Weiss Syndrome (MWS), characterized by spontaneous adult-onset tarsal navicular osteonecrosis, is an uncommon cause of chronic midfoot pain that can lead to functional impairment and progressive deformities. This study aimed to present clinical and radiological outcomes of talonavicular-cuneiform (TNC) arthrodesis in the treatment of patients with MWS. A retrospective study was performed on 8 consecutive patients (6 female, 2 male; mean age = 50 years; range = 33-64) who underwent TNC arthrodesis using plate fixation with autologous bone grafting for the treatment of MWS. To evaluate clinical status, the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Midfoot Score was performed immediately preoperatively and at the final follow-up. In radiographic evaluation, talus-first metatarsal angle (Meary's angle) was measured preoperatively and at the final follow-up. Solid fusion was also examined on postoperative radiographs and computerised tomography. The mean follow-up was 35 months (range = 24-52). The mean AOFAS improved from 37 (range = 24-53) preoperatively to 85 (range = 80-93) at the final follow-up (p < 0.001). No major intra- operative complications were observed in any of the patients. According to the Maceira and Rochera radiological staging system, 5 feet was stage 3, and 3 feet was stage 4. The mean union time was 10 months (range = 5-15). Radiographic solid fusion was achieved in all but one foot that developed talonavicular non-union. TNC arthrodesis using plate fixation with autologous bone grafting seems to be an effective surgical method for reconstruction of MWS.

Anatomic Description of the Calcaneocuboid Joint: Implications for Staple Fixation.

Understanding the anatomy of the calcaneocuboid (CCJ) remains essential when selecting staple fixation to optimize osseous purchase during rearfoot procedures. This anatomic study quantitatively describes the CCJ in relation to staple fixation sites. The calcaneus and cuboid from 10 cadavers were dissected. Widths at 5 mm and 10 mm increments away from the joint were measured in dorsal, midline, and plantar thirds of each bone. The widths between each position's 5 mm and 10 mm increments were compared using the Student's t test. The widths among the positions at both distances were compared using an ANOVA then post hoc testing. Statistical significance was set at p ≤ 0.05. The middle (23 ± 3 mm) and plantar third (18 ± 3 mm) of the calcaneus at the 10 mm interval was greater than the 5 mm interval (p = .04). At 5 mm distal to the CCJ, the dorsal third of the cuboid maintained a statistically significant greater width than the plantar third (p = .02). The 5 mm (p = .001) and 10 mm (p = .005) dorsal calcaneus widths as well as the 5 mm (p = .003) and 10 mm (p = .007) middle calcaneus widths were significantly greater than the plantar widths. This investigation supports the use of 20 mm staple 10 mm away from the CCJ in dorsal and midline orientations. Care should be taken when placing a plantar staple within 10 mm proximal to the CCJ as the legs may extend beyond the medial cortex compared to dorsal and midline placements.

Long-term Outcomes of Talonavicular Arthrodesis for the Treatment of Planovalgus Foot in Children With Cerebral Palsy.

BACKGROUND: Planovalgus foot (PVF) in cerebral palsy (CP) tends toward progression and rigidity in adolescence, especially in patients with greater functional impairment. Deformity at the talonavicular joint justifies the use of talonavicular arthrodesis as a corrective surgical technique. This study aims to assess patient or caregiver functional satisfaction and radiographic outcomes of talonavicular arthrodesis for PVF in CP patients with assisted ambulation in the long-term. METHODS: Retrospective comparative study of level III and level IV pediatric CP patients who underwent talonavicular arthrodesis for PVF between 1999 and 2010 as part of multilevel surgery and with a minimum follow-up of 10 years. Radiologic correction at 10 years was compared with preintervention values, and functional impact at 10 years was measured by the foot function index (FFI); correlation between radiologic measurements and FFI were obtained, and complications were recorded. RESULTS: Forty-nine PVFs in 25 patients with CP (72% level III and 28% level IV) were included; 52% were male. The patients had a median age of 12 years at the time of surgery (range: 11 to 15) and 23 years at the time of the study (21 to 26). Significant (P<0.01) pre-post radiologic improvements were obtained in Meary angle (37.86±10.7/8.37±5.5 degrees), calcaneal pitch (3.20±8.1/13.22±5.6 degrees), lateral talocalcaneus angle (42.18±12.1/25.29±2.9 degrees), Moreau-Costa-Bartani angle (167.04±8/146.12±7.1 degrees), talus-first metatarsal angle (27.92±13.9/9.69±4.4 degrees), anteroposterior talocalcaneal angle (37.61±7.4/22.61±2.4 degrees), and talus coverage angle (37.04±11.11/2.45±2.5 degrees). At 10 years postoperatively, functional outcome measured with the FFI was satisfactory (33.9±15.2%) and the mean maximum pain was 3.04; 56% of cases had mild pain. All patients were able to wear an ankle-foot orthosis and 8 no longer needed the device. A significant correlation was found between the talofirst metatarsal angle and the FFI (P=0.024). There were 8% of cases with screw protrusion and 14% presented pseudarthrosis, most of them asymptomatic. CONCLUSIONS: The adequate functional outcome, as well as the persistence of long-term radiologic correction and acceptable number of complications, enables us to recommend talonavicular arthrodesis as an alternative treatment to consider in level III and level IV CP patients with PVF. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

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.

Coronal Hindfoot Alignment in Midfoot Charcot Neuroarthropathy.

Coronal plane hindfoot malalignment produces abnormal compensatory forces within the midfoot and forefoot. The primary aim of this study is to compare radiographic hindfoot alignment in patients with a midfoot Charcot event, and identify patterns associated with breakdown. A retrospective review of 43 patients (48 limbs) with midfoot Charcot neuroarthropathy were compared between the coronal hindfoot alignments and Charcot joint involvement. Coronal hindfoot alignment was classified as neutral (n = 15), valgus (n = 16), and varus (n = 17) utilizing the Saltzman hindfoot alignment radiograph. Charcot joint breakdown was classified as isolated tarsometatarsal joint (n = 8), combination of tarsometatarsal and naviculocuneiform joints (n = 22), and midtarsal joints including talonavicular and calcaneocuboid joints (n = 18). Patients exhibiting varus hindfoot alignment had 5.8 times greater risk of breakdown at the tarsometatarsal and naviculocuneiform joints (odds ratio 5.8, 95% confidence interval 1.7-22.9, p < .01). Hindfoot varus induces external rotation of the talus, resulting in compensation through the naviculocuneiform and tarsometatarsal joint, which correlates with our findings of a 6-fold increase in naviculocuneiform and tarsometatarsal joint collapse. Patients exhibiting valgus hindfoot alignment had 27 times greater risk of breakdown at the midtarsal joint (odds ratio 27.0; 95% confidence interval 5.6-207.0, p < .01). Hindfoot valgus induces internal rotation of the talonavicular joint, which correlates with our findings of a 27-fold increase in midtarsal joint breakdown. Varus and valgus hindfoot alignment are associated with different midfoot injury patterns, which may have implications in surgical management and allow for focused surveillance in neuropathic patients presenting with early-stage clinical findings consistent with Charcot neuroarthropathy.

Radiographic Outcomes of Talonavicular Joint Arthrodesis With Varying Fixation Techniques in Stage III Adult Acquired Flatfoot Reconstruction.

Utilization of the talonavicular joint (TN) arthrodesis as an isolated procedure or in combination with hindfoot arthrodesis has been described in the literature for treatment of numerous hindfoot conditions. When used in isolation or with concomitant hindfoot arthrodesis, the TN joint has demonstrated nonunion rates reported as high as 37% in the literature. Despite previous research, there remains a lack of agreement upon the ideal fixation technique for TN joint arthrodesis with and without concomitant subtalar joint arthrodesis. The purpose of this study was to retrospectively compare the radiographic and clinical results of TN joint arthrodesis as part of double arthrodesis procedure utilizing 4 separate fixation constructs in the treatment of advanced hindfoot malalignment in stage III adult-acquired flatfoot deformity. We retrospectively reviewed 105 patients who underwent TN joint arthrodesis as part of double arthrodesis procedure utilizing 4 separate fixation constructs. Our results demonstrated a nonunion rate of 16.2%, with 17 nonunions identified within our patient population. One (2.4%) nonunion was observed in the 3-screw cohort, 7 (33.3%) nonunions were observed in the 2-screw cohort, 4 (16.0%) nonunions were observed in the 2-screw plus plate cohort, and 5 (29.4%) nonunions were observed in the 1-screw plus plate cohort. The difference in nonunion rate between the 4 cohorts was statistically significant. Based on these results, we conclude that the use of a 3-screw construct for TN joint arthrodesis as part of double arthrodesis procedure demonstrates a statistically significant reduction in nonunion rate and should be considered a superior fixation construct for this procedure.

The transverse arch in the human feet: A narrative review of its evolution, anatomy, biomechanics and clinical implications.

The dominant characteristics of the human foot are its shock-absorbing capability during walking or gait cycle and its adaptation to uneven surfaces. On the stance phase of the gait, the foot has to be flexible at first for shock absorption and adapt to the terrain; whereas, during the propulsive phase, it has to be dynamically rigid to function as a lever. Foot flexibility and rigidity are mainly controlled at the subtalar and midtarsal joints by tendons and ligaments. The subtalar joint is part of the longitudinal arch, but the midtarsal joint along with the tarsometatarsal joint are components of the transverse arch. However, the existence and functional role of transverse arch in human was challenged by some authors. But recent studies have revealed that the transverse arch has a predominant role in midfoot stiffness (Venkadeshan et al., 2020, & Holowoka et al., 2017). This midfoot stiffness allows the human foot to store elastic energy at the time of heel strike, which is utilized during the push-off mechanism for propulsion, thus making bipedalism more energy-efficient. Moreover, the transverse arch allows the longitudinal arch to be flexible like a lever and, at the same time, makes the arch of the foot rigid to behave like a stiff spring lever. Understanding the role of the transverse arch is obligatory to study the biomechanics of foot injuries and Charcot or diabetic foot. Studies on diabetic foot have shown that the modulation of transverse arch biomechanics and off-loading modalities would improve outcomes in the form of wound-healing and prevention of re-ulceration.

Classification of the interosseous tarsometatarsal ligaments of the foot.

BACKGROUND: The aim of this study was to clarify the anatomical features of the interosseous tarsometatarsal ligaments of foot and to classify their types based on the combinations of their ligamentous components. METHODS: Fifty feet from 27 adult Korean cadavers were dissected. RESULTS: The interosseous tarsometatarsal ligaments were observed in the first, second, and third cuneometatarsal joint spaces. The interosseous tarsometatarsal ligament of the first cuneometatarsal space consistently connected the medial cuneiform and the second metatarsal, and was accompanied by one or two accessory ligaments above (34%) and/or below (6%) the Lisfranc ligament. The interosseous tarsometatarsal ligaments of the second and third cuneometatarsal joint spaces comprised seven and five components, and were classified into five and three types depending on the number and combination of the components, respectively. CONCLUSIONS: These results are expected to advance the current knowledge on the tarsometatarsal joint and provide helpful information for more accurate and successful diagnosis and treatment of lesions at this joint.

Which surgical approach is optimal for joint preparation in talonavicular fusion - A cadaver study.

BACKGROUND: Fusion of the talonavicular joint has proven challenging in literature. The optimal surgical approach for talonavicular arthrodesis is still uncertain. This study compares the amount of physical joint preparation between dorsal and medial approaches to the talonavicular joint. METHODS: Twenty fresh frozen cadaver specimens were randomly assigned to receive either a dorsal or medial operative approach to the talonavicular joint. The joint surface was prepared, and the joint was disarticulated. Image analysis, using ImageJ, was performed by two blinded reviewers to assess the joint surface preparation and this was compared by surgical approach. RESULTS: The dorsal approach had a higher median percentage of talar and total talonavicular joint surface area prepared (75% vs. 59% (p = .007) and 82% vs. 70% (p = .005)). Irrespective of approach, the talus was significantly more difficult to prepare than the navicular (62% vs 88% (p = .001)). CONCLUSION: The dorsal approach provides superior talonavicular joint preparation. The lateral »th of the talar head was the most difficult surface to prepare, and surgeons performing double or triple arthrodesis may prepare the lateral talar head from the lateral approach. LEVEL OF EVIDENCE: Level V.

Comparison of each bundle of the spring ligament complex between the standing and supine positions: A multiposture magnetic resonance imaging study.

BACKGROUND: The spring ligament complex (SLC) supports the medial longitudinal arch of the foot, particularly in standing. We evaluated posture-related changes in the thickness and length of the three SLC bundles and their histology. METHODS: The thickness and length of the supramedial calcaneonavicular ligament (smCNL), medioplantar oblique calcaneonavicular ligament (mpoCNL), and inferoplantar calcaneonavicular ligament (iplCNL) were measured in the supine and standing positions, using a multiposture magnetic resonance imaging system, in 72 healthy adult feet. Histological examination was performed for 10 feet from five cadavers. RESULTS: The smCNL thickness decreased and its length increased from the supine to the standing position (P < 0.001); no other posture-related effects were noted. Histologically, smCNL fibers overlapped along multiple directions while mpoCNL and iplCNL, fibers were oriented horizontally along the longitudinal axis and vertically along the short axis, respectively. CONCLUSION: The complex, multidirectional, orientation of the smCNL allows an adaptive response to changes in loading.

Loss of Mechanical Ankle Function Is Not Compensated by the Distal Foot Joints in Patients with Ankle Osteoarthritis.

BACKGROUND: Patients with isolated ankle osteoarthritis (OA) often demonstrate disturbed ankle biomechanics during walking. Clinicians often believe that this triggers the distal foot joints to compensate these altered ankle biomechanics and that these foot joints are consequently subjected to degenerative joint diseases due to overuse. QUESTIONS/PURPOSES: Do patients with isolated ankle OA differ from those without ankle OA in terms of (1) ankle and foot joint kinematics and (2) ankle and foot joint kinetics as measured using three-dimensional (3-D) gait analysis? (3) Do these patients demonstrate compensatory strategies in their Chopart, Lisfranc, or first metatarsophalangeal joints in terms of increased joint kinematic and kinetic outputs? METHODS: Between 2015 and 2018, we treated 110 patients with unilateral ankle OA, and invited all of them to participate in the gait analysis laboratory. Of those, 47% (52) of patients did so, and of these, 16 patients met the inclusion criteria for this study, which were (1) diagnosis of unilateral ankle OA; (2) absence of radiographical signs of OA in the contralateral foot or lower limbs; (3) ability to walk at least 100 m without rest; and (4) being older than 18 years of age. A control group (n = 25) was recruited through intranet advertisements at the University Hospitals of Leuven. Participants were included if their age matched the age-range of the patient group and if they had no history of OA in any of the lower limb joints. Patients were slightly older (55.9 ± 11.2 years), with a slightly higher BMI (28 ± 6 kg/m2) than the control group participants (47.2 ± 4.4 years; p = 0.01 and 25 ± 3 kg/m2; p = 0.05). All participants underwent a 3-D gait analysis, during which a multisegment foot model was used to quantify the kinematic parameters (joint angles and ROM) and the kinetic parameters (rotational forces or moments), as well as power generation and absorption in the ankle, Chopart, Lisfranc, and first metatarsophalangeal joints during the stance phase of walking. Peak values were the maximum and minimum values of waveforms and the latter were time-normalized to 100% of the stance phase. RESULTS: Regarding joint kinematics, patients demonstrated a sagittal plane ankle, Chopart, Lisfranc, and first metatarsophalangeal joint ROM of 11.4 ± 3.1°, 9.7 ± 2.7°, 8.6 ± 2.3° and 34.6 ± 8.1°, respectively, compared with 18.0 ± 2.7° (p < 0.001), 13.9 ± 3.2° (p < 0.001), 7.1 ± 2.0° (p = 0.046) and 38.1 ± 6.5° (p = 0.15), respectively, in the control group during the stance phase of walking. With regard to joint kinetics in the patient group, we found a mean decrease of 1.3 W/kg (95% CI confidence interval 1.0 to 1.6) (control group mean: 2.4 ± 0.4 W/kg, patient group mean: 1.1 ± 0.5 W/kg) and 0.8 W/kg (95% CI 0.4 to 1.0) (control group mean: 1.5 ± 0.3 W/kg, patient group mean: 0.7 ± 0.5 W/kg) of ankle (p < 0.001) and Chopart (p < 0.001) joint peak power generation. No changes in kinetic parameters (joint moment or power) were observed in any of the distal foot joints. CONCLUSION: The findings of this study showed a decrease in ankle kinematics and kinetics of patients with isolated ankle OA during walking, whereas no change in kinematic or kinetic functions were observed in the distal foot joints, demonstrating that these do not compensate for the mechanical dysfunction of the ankle. CLINICAL RELEVANCE: The current findings suggest that future experimental laboratory studies should look at whether tibiotalar joint fusion or total ankle replacement influence the biomechanical functioning of these distal joints.

Finite element analysis of the kinematic coupling effect of the joints around talus when Ponseti manipulation.

BACKGROUND: Little information was obtained from the published papers about the kinematic coupling effect between tarsal bones during Ponseti manipulation. The aim was to explore the kinematic coupling effect of the joints around talus, to investigate the kinematic rhythm and coupling relationship of tarsal joints; to clarify the pulling effect on medial ligament of the ankle during the process of Ponseti manipulation. METHODS: The model of foot and ankle was reconstructed from the Chinese digital human girl No.1 (CDH-G1) image database. Finite element analysis was applied to explore the kinematic coupling effect of the joints around talus. The distal tibia and fibula bone and the head of talus were fixed in all six degrees of freedom; outward pressure was added to the first metatarsal head to simulate the Ponseti manipulation. Kinematic coupling of each tarsal joint was investigated using the method of whole model splitting, and medial ligament pulling of the ankle was studied by designing the model of medial ligament deletion during the Ponseti manipulation. RESULTS: All the tarsal joints produced significant displacement in kinematic coupling effect, and the talus itself produced great displacement in the joint of ankle. Quantitative analysis revealed that the maximum displacement was found in the joints of talonavicular (12.01mm), cuneonavicular (10.50mm), calcaneocuboid (7.97mm), and subtalar(6.99mm).The kinematic coupling rhythm between talus and navicular, talus and calcaneus, calcaneus and cuboid, navicular and cuneiform 1 were 1:12, 1:7, 1:2 and 1:1.6. The results of ligaments pulling showed that the maximum displacement was presented in the ligaments of tibionavicular (mean 27.99mm), talonavicular (21.03mm), and calcaneonavicular (19.18 mm). CONCLUSIONS: All the tarsal joints around talus were involved in the process of Ponseti manipulation, and the strongest kinematic coupling effect was found in the joints of talonavicular, subtalar, calcaneocuboid, and cuneonavicular. The ligaments of tibionavicular, talonavicular, and calcaneonavicular were stretched greatly. It was suggested that the method of Ponseti management was a complex deformity correction processes involved all the tarsal joints. The present study contributed to better understanding the principle of Ponseti manipulation and the pathoanatomy of clubfoot. Also, the importance of cuneonavicular joint should be stressed in clinical practice.

Do We Really Need to Worry About Calcaneocuboid Subluxation During Lateral Column Lengthening for Planovalgus Foot Deformity?

BACKGROUND: Although lengthening of the lateral column through an osteotomy of the anterior calcaneus is an integral component of flatfoot reconstruction in younger patients with flexible planovalgus deformities, the procedure has been implicated in iatrogenic calcaneocuboid (CC) subluxation and subsequent degenerative changes at the CC articulation. The purpose of this study is to characterize alterations at the CC joint after lateral column lengthening (LCL) and determine if Steinmann pin stabilization of the CC joint before distraction maintains a normal relationship. METHODS: Seven matched pairs of fresh-frozen cadaveric feet underwent preprocedure plain radiography and cross-sectional computed tomography (CT) imaging. LCL by osteotomy through the anterior calcaneus was then performed. One foot of each matched pair had a single smooth Steinmann pin placed centrally across the CC joint before osteotomy distraction. Distraction across each osteotomy was then performed and maintained with a 12-mm porous titanium wedge. Repeat imaging was obtained and compared with preprocedure studies to quantify sagittal and rotational differences at the CC articulation. RESULTS: Following LCL, plain radiography demonstrated statistically significant increases in the percentage of the calcaneal articular surface dorsal to the superior aspect of the cuboid in both the pinned (8.2% vs. 17.6%, P=0.02) and unpinned (12.5% vs. 16.3%, P=0.04) specimens. No difference in the percentage of subluxation was found between the 2 groups after LCL. CT imaging demonstrated statistically significant increases in rotation between the calcaneus and cuboid after LCL in both the pinned (7.6±5.6 degrees, P=0.01) and unpinned (17±12.3 degrees, P=0.01) specimens. The degree of rotation was greater in unpinned specimens after LCL (P=0.043). CONCLUSIONS: Both sagittal and rotatory subluxation seem to occur at the CC joint after LCL regardless of pin stabilization. As a single pin would be expected to limit pure translation while having little effect on rotation, it is possible that the rotational changes identified on 3-dimensional imaging are interpreted as dorsal translation when viewed 2 dimensionally using plain radiography. Consideration should therefore be given to CC stabilization with 2 pins during LCL to prevent this rotatory subluxation. LEVEL OF EVIDENCE: Level V-cadaver study.

Charcot Arthropathy of Foot and Ankle: Radiographic and Clinical Patterns with Related Outcomes.

PURPOSE: Our aim is to retrospectively review and evaluate the patterns of affection of Charcot arthropathy of foot and ankle. METHODS: Two hundred twenty-eight patients (235 feet) with post-acute Charcot were reviewed and classified anatomically through plain radiographs into type I and type II based on single or multiple regions affected, respectively. Type I included ankle, Lisfranc (tarsometatarsal), naviculocuneiform, forefoot, and hindfoot which includes one of the following: talonavicular joint, calcaneocuboid joint, or calcaneus. Type II included peritalar, perinavicular, mid-tarsal Charcot, or any other combination. Both types were further classified into four stages (A, stable with no deformity; B, stable with deformity; C, unstable; and D, deformity/instability with associated mechanical ulcers). RESULTS: The most common type was type IIC (27.2%) followed by type IID (18.3%), while types IA and IIA represented the least common types (3.4% and 3.8%, respectively). Types IA and IIA were managed conservatively. All patients in types IC, ID, IIB, IIC, and IID and the majority of type IB received fusion surgery to achieve stability and correction of deformity. Type II D had the highest complication rate (30%). Five patients ended up with amputation, and all were stage IID. CONCLUSION: Affection of single region has better prognosis than affection of two or more regions. Stage A has the best prognosis and can be managed conservatively provided good diabetes control. Surgery is indicated in all cases of types IC, ID, IIB, IIC, and IID to achieve stability and correction of deformity and prevent complications. Mechanical ulcer (stage D) carries the worst prognosis and highest complication rate.

Anatomic Description of the Distal and Intercuneiform Articulations: A Cadaveric Study.

The medial, intermediate, and lateral cuneiforms play a pivotal role in foot biomechanics. When correcting deformities of this joint complex understanding the clinical anatomy remains imperative to provide both anatomic reduction and appropriately sized fixation. This study qualitatively and quantitatively describes the distal and intercuneiform articulations and their clinical implications. The cuneiform complex of 10 fresh-frozen cadavers was dissected, and the width of the complex was measured with digital calipers. Following further dissection, the distal articular surface shapes of each cuneiform were described, and the individual heights and widths were measured. The intercuneiform articular facets were described and the protrusion distances, between the medial and lateral cuneiforms with the intermediate cuneiform, were measured. The width of the joint complex was 44.74 ± 3.40 mm. The medial cuneiform height, width, dorsal anterior, and plantar protrusion distances were 32.58 ± 2.77 mm, 14.08 ± 2.26 mm, 8.51 ± 2.17 mm, and 6.66 ± 1.21 mm, respectively. The intermediate cuneiform height and width was 23.05 ± 1.92 mm and 9.59 ± 1.85 mm, respectively. The lateral cuneiform height, width, dorsal, and plantar anterior protrusion distances were 23.38 ± 2.67 mm, 10.98 ± 3.01 mm, and 6.76 ± 1.43 mm, and 4.19 ± 1.10 mm respectively. The anterior surface of the medial, intermediate, and lateral cuneiforms was described as reniform, triangular, and triangular, respectively. The majority of intermediate cuneiforms shared an inverted L-shaped articulation with the medial cuneiform, and a B-shaped articulation with the lateral cuneiform. The shapes and sizes of distal and intercuneiform articulations were described with shared anatomical features across cadavers. Understanding the dimensions of the respective surfaces allows for anatomically appropriate fixation size.

Load to Failure of the Ankle Joint Complex After Fusion of the Subtalar and Talonavicular Joints: A Cadaveric Study.

Recent literature has proposed that restriction of joints in the rearfoot secondary to coalitions may lead to increased risk for severe ankle fracture after trauma. There is a paucity of literature regarding the rigidity of the ankle joint after arthrodesis of the subtalar and talonavicular joints. In this study, load-to-failure testing of cadaveric ankle joints with and without fusion of the subtalar and talonavicular joints was performed to determine if clinically relevant fracture patterns could be reproduced. Of the 3 fixation patterns studied, combined subtalar and talonavicular joint fusion resulted in a measurable increase in joint stiffness; however, this was not statistically significant. Clinical and radiographic examination postloading revealed that all tested ankle joints sustained a dislocation type injury rather than a specific bone fracture pattern. It was determined that a pure low-speed bending and compression model does not produce clinically relevant fracture patterns, and that higher energy mechanisms are required.

Pre and Postoperative Analysis of Flatfoot Reconstruction Sparing the Talonavicular Joint.

Surgical correction of a flatfoot deformity is controversial. The purpose of our study was to evaluate the structural radiographic changes of the flatfoot deformity while maintaining the mobile adapter of the foot. We conducted a retrospective analysis of 56 patients that underwent this procedure comparing their pre- to postoperative angular changes during a follow-up period. The mean age of our study cohort was 53.6 (range, 20-77) years and mean follow-up period was 23 (range, 4-73) months. Radiographic union was achieved in 48 patients (86%). Forty-six patients (82%) had all required radiographs completed through final follow-up visit. We illustrated statistically significant changes to the talonavicular, Meary, talocalcaneal, calcaneal inclination, and talar declination angles, and navicular height at 3 months and final follow-up. This study suggests surgical correction of the flatfoot deformity that fused the subtalar but spared the talonavicular joint appears to achieve and maintain radiographic angular changes and achieve union.