Fourth Metatarsophalangeal Joints Research Articles

Foot Posture Index Does Not Correlate with Dynamic Foot Assessment Performed via Baropodometric Examination: A Cross-Sectional Study.

Clinicians employ foot morphology assessment to evaluate the functionality of the method and anticipate possible injuries. This study aims to correlate static foot posture and the dynamic barefoot evaluation in a sample of healthy adult participants. The foot posture was evaluated using the Foot Posture Index-6 (FPI-6) and the dynamics were evaluated through baropodometric examination. Two operators independently assessed the participants' foot posture through FPI-6, and then a dynamic evaluation was performed by asking them to walk 8 times across a platform. One hundred participants (mean age: 32.15 ± 7.49) were enrolled. The inter-rater agreement between the two assessors was found to be excellent. The majority of the feet belonged to the 0 < FPI < 4 class (32%), followed by the 4 < FPI < 8 (31%) and the FPI > 8 ranges (19.5%). Our "area of contact" analysis showed a significant poor correlation between FPI and total foot, midfoot, and the second metatarsophalangeal joint (MTPJ) (-0.3 < r < 0). Regarding "force" parameters, the analysis showed a poor correlation between the midfoot, hallux, and the second toe (-0.2 < r < 2); finally the "pressure" analysis showed a poor correlation between FPI, the fourth MTPJ, and the second toe (-0.2 < rs < 0.3) and a moderate correlation between the hallux (r = 0.374) and the fifth MTPJ (r = 0.427). This study emphasizes the constrained correlation between static foot posture observation and dynamic barefoot examination.

Progressive First Metatarsal Shortening Is Observed Following Allograft Interpositional Arthroplasty in Hallux Rigidus

Introduction/Purpose: Interpositional arthroplasty (IPA) is a motion-preserving surgery in patients with advanced hallux rigidus. Literature displays several complications after the procedure including transfer metatarsalgia, cock-updeformity and infection. In a finite element model, shortening of the first metatarsal was associated with increased plantar pressure on lateral rays during gait. Additionally, there are reports of a positive correlation between first metatarsal shortening after hallux valgus surgery and transfer metatarsalgia of the second,third and fourth metatarsophalangeal joints. The goals of this study were to report the outcomes and complications of IPA using acellular dermal allograft (IPA-ADA) as well as study the changes in the length of the proximal phalanx of the hallux (P1) and the first metatarsal (M1) following the procedure. Methods: In this IRB-approved retrospective study, we assessed patients who underwent IPA-ADA in a single academic institute from 2019-2022. All patients’ demographic data, surgical details, complications, and patient-reported outcomes (PROs) were extracted. On standing conventional anteroposterior (AP) foot views, we measured the lengths of the first metatarsal (M1), the second metatarsal (M2), the proximal phalanx of the big toe (P1), and the entire length of the hallux (HX). The ratio of M1/M2 and P1/HX were calculated. The first metatarsophalangeal joint space was measured at the medial and lateral aspects of the joint on the APview. All measurements were recorded pre-operatively, at six weeks follow-up, and at the final follow-up. Descriptive statistics were performed, and comparison between groups was performed using analysis of variance(ANOVA) or Kruskal Wallis test according to data normality. The Dunn-Bonferroni test was then performed for pairwise group comparisons. A p-value &lt; 0.05 was considered significant. Results: Eleven patients were included, 9 being females (81.81%). Six were hallux rigidus Coughlin grade III (54.55%), and 5 were grade IV (45.45%). The average age was 59 years (SD±6.78), and the body mass index (BMI) was 26 (SD±4.79). At the final follow- up, there was significant shortening of the first ray in comparison to the pre-operative length evidenced by lower M1/M2 (82.63 SD±2.29 versus 75.42 SD±5.1; p=0.001) and P1/HX ratio53.38 ± 2.29 versus 48.98 SD ± 7.92; p=0.001). Although there was no significant difference between M1/M2 at 6 weeks and at the final follow-up (p=0.716), there was a significant negative correlation between follow-up length and M1/M2 (r= -0.76, p=0.003). Follow-up was (19.95 months; range 3-39). Complications and PROs are listed in Figure 1. Conclusion: Interposition arthroplasty using dermal allograft for HR is associated with progressive shortening of the first ray at the level of the first metatarsal as well as the proximal phalanx. Although the study did show shortening of the first ray, the small sample size didn't allow for a correlation between this shortening and complications such as transfer metatarsalgia and cock-up toe deformity. The potential shortening should be considered in the selection of patients, particularly in the setting of an already short first metatarsal or when simultaneous Akin/Moberg osteotomy is planned. Interposition arthroplasty using dermal allograft for HR is associated with progressive shortening of the first ray at the level of the first metatarsal as well as the proximal phalanx. Although the study did show shortening of the first ray, the small sample size didn't allow for a correlation between this shortening and complications such as transfer metatarsalgia and cock-up toe deformity. The potential shortening should be considered in the selection of patients, particularly in the setting of an already short first metatarsal or when simultaneous Akin/Moberg osteotomy is planned.

Clinical comparative study on resection and non-resection of the fifth metatarsal to rheumatoid forefoot deformity

To explore clinical effect of the fifth metatarsal head excision and non-excision in rheumatoid arthritis (RA) forefoot deformity reconstruction. Retrospective analysis was performed on 50 patients (76 feet) with moderate to severe forefoot deformity caused by RA treated from May 2015 to January 2019. According to degeneration of the fifth metatarsophalangeal joint,the fifth metatarsal head was retained or excised by wind-like forefoot reconstruction,and divided into the fifth metatarsal head preservation group (preservation group) and the fifth metatarsal head resection group (resection group). Twenty-four female patients in preservation group,aged from 47 to 81 years old with an average of (60.37±8.60) years old;the course of disease ranged from 13 to 22 years with an average of (19.00±3.06) years;body mass index (BMI) ranged from 21 to 28 kg·m-2 with an average of (23.53±2.47) kg·m-2;six patients (6 feet) with moderate hallux valgus deformity and 18 patients (30 feet) with severe hallux valgus deformity;treated with the first metatarsophalangeal joint fusion combined with the second th the fourth metatarsophalangeal joint arthroplasty and the fifth metatarsophalangeal joint cleanup. Twenty-six female patients in resection group were female,aged from 30 to 80 years old with an average of (58.53±13.70) years old;the course of disease ranged from 8 to 25 years with an average of (17.94±3.92) years;BMI raged from 20 to 28 kg·m-2 with an average of (24.60±2.03) kg·m-2;4 patients (4 feet) with moderate bunion valgus deformity and 22 patients (36 feet) with severe bunion valgus deformity;treated by the first metatarsophalangeal joint fusion combined with the second th the fifth metatarsophalangeal joint resection of the metatarsophalangeal head. Operation time and postoperative complications between two groups were observed,hallux valgus angle (HVA),intermetatarsal angles between the first and the second metatarsals (IMAFS),intermetatarsal angles between the first and fifth metatarsals (IMAFF),Japanese Society for Surgery of Foot (JSSF) score before surgery and at the latest follow-up were compared. Fifty patients were followed-up from 14 to 46(25.30±8.83) months in resection group and 12 to 48 with an average of (24.30±11.12) months in preservation group,while no significant difference between two groups (P>0.05). There were no significant difference in operation time and postoperative complications between two groups (P>0.05). JSSF scores,HVA,IMAFS and IMAFF in fesection group were improved from (45.09±3.35) points,(38.90±13.67) °,(12.88±1.72) °,(32.50±2.99) ° before operation to (81.60±3.27) points,(15.40±0.90),(9.06±2.27) °,(22.20±1.98) ° at the latest follow-up (P<0.05);preservation group were improved from (47.09±3.96) points,(43.30±12.65) °,(13.99±3.13) °,(33.20±6.14) ° to (83.10±3.66) points,(15.20±1.54) °,(8.99±1.02) °,(24.70±1.88) °,respectively. There were no significant difference in JSSF score,HVA,IMAFS and IMAFF between two groups before operation and the latest follow-up (P>0.05). At the latest follow-up,there were statistically significant differences in pain and deformity in JSSF scores between two groups (P<0.05). Both rheumatoid anterior foot reconstruction and anterior foot reconstruction fifth metatarsophalangeal joint debridement showed significant improvement in clinical efficacy and imaging results. Compared with rheumatoid prefoot reconstruction,the fifth metatarsophalangeal joint reconstruction for the treatment of moderate and severe deformity of rheumatoid prefoot showed better improvement in pain,but worse improvement in deformity. For the moderate to severe deformity of the forefoot caused by rheumatoid disease,patients with mild to moderate degenerative deformity of the articular surface of the fifth metatarsal phalanges may be considered for use.

Improvement of Valgus Deviation of the Lesser Toes of Moderate to Severe Hallux Valgus After Proximal Chevron Metatarsal Osteotomy and Akin Osteotomy.

This study examines the correction of lesser toe valgus deviation following proximal chevron metatarsal osteotomy (PCMO) and Akin osteotomy in moderate to severe hallux valgus patients, while identifying influencing factors. Among 89 patients (116 feet), those with moderate to severe hallux valgus underwent PCMO and Akin osteotomy. Radiologic assessments included preoperative metatarsus adductus angle (MAA), hallux valgus angle (HVA), intermetatarsal angle (IMA), valgus angles of the second to fourth metatarsophalangeal joints, and hallux valgus recurrence. Assessments included visual analog scale (VAS) pain scores, American Orthopaedic Foot & Ankle Society (AOFAS) scores, and patient satisfaction over an average follow-up of 30.6 ± 21.2 (range, 12-99) months. The mean preoperative HVA of 34.4 degrees decreased to 8.7 degrees at final follow-up. The valgus angles of the second, third, and fourth toes improved by 37.1%, 27%, and 44.5%, respectively. In metatarsus adductus patients, lesser toe valgus angles were significantly higher both preoperatively and at final follow-up. Hallux valgus recurrence patients had higher preoperative and final follow-up IMA and valgus angles in the second and third toes. Nonrecurrence patients showed greater decreases in these angles. A larger HVA correction corresponded to a greater decrease in lesser toe valgus deviation. VAS and AOFAS scores improved significantly at the last follow-up. The study found a significant reduction in the valgus angle of the second, third, and fourth toes after PCMO and Akin osteotomy in moderate to severe hallux valgus cases, without additional surgeries on lesser toes. The lesser toe angular reductions were less pronounced in patients with metatarsus adductus or with hallux valgus recurrence. Level IV, case series.

Distribution of Sesamoid Bones in the Foot and Hand Radiographs; A Descriptive Cross-Sectional Study in a Tertiary Care Center in Nepal

Objective: The aim of this study was to present data about the prevalence and distribution of sesamoid bones of the hands and feet in Nepalese population by using radiographs, to determine the number of the sesamoid bones of the foot and hand, commonest site of occurrence and to correlate the findings between gender and age. Methodology: This prospective quantitative study was performed in the Department of Radiology and Imaging, TUTH. The radiographs of foot and hand were reviewed to evaluate the presence or absence of sesamoid bones and patient demographics were also noted. Data collection was done for a period of three months and random probability sampling method was used. Results: This study resulted that in foot radiographs, the most common sites of sesamoid bones was first metatarsophalangeal joint (1st MTPJ) where two sesamoid bones were found, whereas single sesamoid bone was found in other sites. The percentage of sesamoid bones in first interphalangeal joint (1st IPJ), second metatarsophalangeal joint (2nd MTPJ), third metatarsophalangeal joint (3rd MTPJ), fourth metatarsophalangeal joint (4th MTPJ) and fifth metatarsophalangeal joint (5th MTPJ) were 7.9%, 15.4%, 0 %, 0.4%, and 26.7% respectively. The number of sesamoid bones ranged from 2- 5 in single foot with frequency of occurrence of 2 bones being highest (58.3%). The percentage of sesamoid bones in foot was found to be relatively higher in female than male. In the analysis of hand radiographs, the most common sites of sesamoid bones was 1st MCPJ ( single sesamoid bone in 80.33% and a pair of sesamoid bones in 19.67% ) .The percentage of sesamoid bones in 1st IPJ, 2nd MCPJ, 3rd MCPJ, 4th MCPJ and 5th MCPJ were 37.33%, 58.67% ,5.33% , 5.33% and 59.33% respectively. The number of sesamoid bones ranged from 1 - 6 in single hand with frequency of occurrence of 3 bones being higher (32%). The percentage of sesamoid bones in hand was relatively higher in male than female. Conclusion: The distribution and frequency of sesamoid bones differ according to sites, gender and age. This study improves the knowledge on distribution of sesamoid bones of the foot and hand and also provides anatomical data that could help clinicians in diagnosis and management of various sesamoid bone disorders in patients who present with pain and discomfort in the foot and hand.

Do Dynamic Plantar Pressures Differ Based on Sonographic Evidence of Metatarsophalangeal Joint Synovitis in People With Rheumatoid Arthritis?

The metatarsophalangeal joints (MTPJs) are the most common location for synovitis in people with rheumatoid arthritis (RA), yet their association with plantar foot pressures has received very little attention. This study aimed to determine whether plantar pressures differed based on sonographic evidence of MTPJ synovitis in people with RA. Ultrasound was used to assess synovitis (grey scale synovial hypertrophy and power Doppler signal) in MTPJs 1 to 5 using the combined EULAR/Outcome Measures in Rheumatology scoring system. Peak pressure (PP) and pressure time integrals (PTIs) were assessed during barefoot walking for seven plantar foot regions (heel, midfoot, first metatarsal, second metatarsal, third to fifth metatarsals, hallux, lesser toes). Mixed-effects linear regression was used to determine the difference in PP and PTI between MTPJs with none/minimal synovitis and MTPJs with moderate/severe synovitis. Thirty-five participants with RA were included. Mean age was 66.3 years and mean disease duration was 22.2 years. Participants with sonographic evidence of moderate/severe synovitis at the first MTPJ had reduced PTI at the hallux compared with those with none/minimal synovitis at this joint (P = 0.039). Participants with moderate/severe synovitis at the second MTPJ and fourth MTPJ had reduced PP and reduced PTI at lesser toes compared with those with none/minimal synovitis in these joints (all P ≤ 0.048). No significant differences were observed for synovitis in other joints. These findings may be suggestive of an inverse relationship between plantar pressure and soft tissue pathology, which is consistent with an offloading strategy and reduced use of the toes during propulsion.

Plantar pressures in people with midfoot osteoarthritis: cross-sectional findings from the Clinical Assessment Study of the Foot

BackgroundMidfoot osteoarthritis (OA) is a common condition, however its aetiology is not well understood. Understanding how plantar pressures differ between people with and without midfoot OA may provide insight into the aetiology and how best to manage this condition. Research questionTo compare plantar pressures between people with and without symptomatic radiographic midfoot OA. MethodsThis was a cross-sectional study of adults aged ≥ 50 years registered with four UK general practices who reported foot pain in the past year. Symptomatic radiographic midfoot OA was defined as midfoot pain in the last four weeks, combined with radiographic OA in one or more midfoot joints. Cases were matched 1:1 for sex and age ( ± 5 years) to controls. Peak plantar pressure and maximum force in 10 regions of the foot were determined using a pressure platform (RSscan International, Olen, Belgium) and compared between the groups using independent samples t-tests and effect sizes (Cohen’s d). ResultsWe included 61 midfoot OA cases (mean age 67.0, SD 8.1, 31 males, 30 females) and matched these to 61 controls (mean age 66.0, SD 7.9). Midfoot OA cases displayed greater force (d=0.79, medium effect size, p = <0.001) and pressure at the midfoot (d=0.70, medium effect size, p = <0.001), greater force at the fourth metatarsophalangeal (MTP) joint (d=0.28, small effect size, p = 0.13), and fifth MTP joint (d=0.37, small effect size, p = 0.10) and greater pressure at the fifth MTP joint (d=0.34, small effect size, p = 0.13). They also displayed lower force (d=0.40, small effect size, p = 0.02) and pressure at the hallux (d=0.50, medium effect size, p = <0.001) and lower force (d=0.54, medium effect size, p = <0.001) and pressure at the lesser toes (d=0.48, small effect size, p = <0.001) compared with controls. SignificanceMidfoot OA appears to be associated with lowering of the medial longitudinal arch, greater lateral push off and less propulsion at toe off. Longitudinal studies are needed to establish causal relationships.

Progressive First Metatarsal Shortening is Observed Following Allograft Interpositional Arthroplasty in Hallux Rigidus

Category: Midfoot/Forefoot; Bunion Introduction/Purpose: Interpositional arthroplasty (IPA) is a motion-preserving surgery in patients with advanced hallux rigidus. Literature displays several complications after the procedure including transfer metatarsalgia, cock-up deformity and infection. In a finite element model, shortening of the first metatarsal was associated with increased plantar pressure on lateral rays during gait. Additionally, there are reports of a positive correlation between first metatarsal shortening after hallux valgus surgery and transfer metatarsalgia of the second, third and fourth metatarsophalangeal joints. The goals of this study were to report the outcomes and complications of IPA using acellular dermal allograft (IPA-ADA) as well as study the changes in the length of the proximal phalanx of the hallux (P1) and the first metatarsal (M1) following the procedure. Methods: In this IRB-approved retrospective study, we assessed patients who underwent IPA-ADA in a single academic institute during the period 2019-2022. All patients’ demographic data, surgical details, complications, and patient-reported outcomes (PROs) were extracted. On standing conventional anteroposterior (AP) foot views, we measured the lengths of the first metatarsal (M1), the second metatarsal (M2), the proximal phalanx of the big toe (P1) and the entire length of the hallux (HX). The ratio of M1/M2 and P1/HX were calculated. The first metatarsophalangeal joint space was measured at the medial and lateral aspects of the joint on the AP view. All measurements were recorded pre-operatively, at six weeks follow-up and at the final follow-up. Descriptive statistics were performed, comparison between groups was performed using analysis of variance (ANOVA) or Kruskal Wallis test according to data normality. The Dunn-Bonferroni test was then performed for pairwise group comparisons.A p-value &lt; 0.05 was considered significant. Results: Eleven patients were included, 9 being females (81.81%). Six were hallux rigidus Coughlin grade III (54.55%) and 5 were grade IV (45.45%). The average age was 59 years (SD±6.78) and the body mass index (BMI) was 26 (SD±4.79). At the final follow- up, there was significant shortening of the first ray in comparison to the pre-operative length evidenced by lower M1/M2 (82.63 SD±2.29 versus 75.42 SD±5.1; p=0.001) and P1/HX ratio 53.38 ± 2.29 versus 48.98 SD ± 7.92; p=0.001). Although there was no significant difference between M1/M2 at 6 weeks and at the final follow-up (p=0.716), there was a significant negative correlation between follow-up length and M1/M2 (r= -0.76, p=0.003). Follow-up was (19.95 months; range 3-39). Complications and PROs are listed in Figure 1. Conclusion: Interposition arthroplasty using dermal allograft for HR is associated with progressive shortening of the first ray at the level of the first metatarsal as well as the proximal phalanx. Although the study did show shortening of the first ray, the small sample size didn't allow for a correlation between this shortening and complications such as transfer metatarsalgia and cock-up toe deformity. The potential shortening should be considered in the selection of patients, particularly in the setting of an already short first metatarsal or when simultaneous Akin/Moberg osteotomy is planned.

Neglected Metatarsophalangeal Joint Dislocation of the Lesser Toe with Associated Metatarsal Fracture Malunion in a 4-Year-Old Child: A Case Report.

A 4-year-old girl presented with a 5-week-old, neglected fourth metatarsophalangeal (MTP) joint dislocation with malunion of the fourth metatarsal. A previous attempt at closed reduction had failed. The reduction was hindered by dynamic stabilizing of soft tissues around the MTP joint. Open reduction of the fourth MTP joint dislocation and corrective osteotomy of the fourth metatarsal was performed. The patient was pain-free without any cosmetic deformity at the 1-year follow-up. Prompt recognition of a MTP dislocation is vital. The long extensor tendon to the toe can hinder the closed reduction of the MTP dislocation. Osteotomy of the metatarsal malunion is necessary for stable reduction. 4.

Vascular Supply to the Proximal Plantar Plate of Lesser Toe Metatarsophalangeal Joint is Primarily Supplied by the Attachment to the Metatarsal: A Nano-CT Microvasculature Study

Category: Lesser Toes Introduction/Purpose: Lesser toe metatarsophalangeal (MTP) instability is implicated in common forefoot pain and deformities. The plantar plate is a major stabilizing structure of the MTP joint with instability frequently occurring after a tear or attenuation of this structure. Previous studies have demonstrated that the blood supply to the proximal plantar plate comes from both the metatarsal and the plantar fascia. Commonly, a McGlamry elevator is used to strip the plantar plate from the plantar surface of the metatarsal to improve exposure of the MTP joint. The vascular consequence of stripping the plantar plate from the metatarsal is not yet well understood. The purpose of this study is to quantify the relative contribution of blood supply to the proximal plantar plate from the metatarsal and plantar fascia. Methods: Twelve fresh-frozen human adult cadaver lower extremity specimens were utilized for this study, resulting in 35 lesser MTP joints that were studied. All specimens were between the ages of 18 and 65 years and had no history of diabetes, peripheral vascular disease, or connective tissue disorders. Specimens with a history of trauma to the foot or ankle, prior foot or ankle surgery, or evidence of clinical deformity of less toes upon inspection were excluded. The specimens were prepared as described previously in Finney et al. The anterior and posterior tibial arteries were perfused with a barium solution and counterstained with phosphomolybdic acid. The second through fourth MTP joints of 12 feet were imaged with nano-computed tomography (nano- CT) at 14-micron resolution. Reconstructed 3D and 2D CT images were utilized for analysis of the volume of vasculature along the metatarsal pedicle and plantar fascia of the proximal plantar plate. Results: Based on nano-CT imaging, the plantar plate specimen demonstrated microvascular infiltration at the proximal attachments of the metatarsal neck, interosseous muscles, periosteum, and plantar fascia (Figure 1). An average of 63.5% of the vascular supply to the proximal portion of the plantar plate entered from the metatarsal pedicle in 35 lesser toe specimens analyzed. The remaining 36.5% of the vascular supply entered from the plantar fascia. The second toes, third toes, and fourth toes had an average of 64.7%, 59.0%, and 67.1% of vasculature supply from the metatarsal pedicle, respectively. The average volume of vasculature from the metatarsal pedicle to the proximal plantar plate was 0.38 mm3, while the average volume of vasculature from the plantar fascia to the proximal plantar plate was 0.19 mm3. Conclusion: The vascular supply of the proximal plantar plate is supplied from both the metatarsal pedicle and plantar fascia. Using the McGlamry elevator for exposure of the MTP joint disrupts the dominant tributary for proximal plantar plate perfusion.

Plantar Pressure Distribution in Patients with Diabetic Peripheral Neuropathy and a First-Ray Amputation.

Elevated dynamic plantar pressures are a consistent finding in diabetic patients with peripheral neuropathy, with implications for plantar foot ulceration. This study aimed to investigate whether a first-ray amputation affects plantar pressures and plantar pressure distribution patterns in individuals living with diabetes and peripheral neuropathy. A nonexperimental matched-subject design was conducted. Twenty patients living with diabetes and peripheral neuropathy were recruited. Group 1 (n = 10) had a first-ray amputation and group 2 (n = 10) had an intact foot with no history of ulceration. Plantar foot pressures and pressure-time integrals were measured under the second to fourth metatarsophalangeal joints, fifth metatarsophalangeal joint, and heel using a pressure platform. Peak plantar pressures under the second to fourth metatarsophalangeal joints were significantly higher in participants with a first-ray amputation ( P = .008). However, differences under the fifth metatarsophalangeal joint ( P = .734) and heel ( P = .273) were nonsignificant. Pressure-time integrals were significantly higher under the second to fourth metatarsophalangeal joints in participants with a first-ray amputation ( P = .016) and in the heel in the control group ( P = .046). Plantar pressures and pressure-time integrals seem to be significantly higher in patients with diabetic peripheral neuropathy and a first-ray amputation compared with those with diabetic neuropathy and an intact foot. Routine plantar pressure screening, orthotic prescription, and education should be recommended in patients with a first-ray amputation.

On the Use of Auxetics in Footwear: Investigating the Effect of Padding and Padding Material on Forefoot Pressure in High Heels

Although high heels are known to affect the biomechanics of human movement, most notably by increasing forefoot plantar pressure, it is commonly worn due to the influence of fashion. To deal with the resulting clinical issues, some prescriptions include the use of cushioning pads to redistribute the plantar loads and increase comfort. This preliminary study has sought to investigate whether auxetic foam would be a good candidate for the redistribution of plantar loafing in the forefoot when compared to a more traditional material. From the results obtained, it was shown that auxetic foam demonstrated a decrease in forefoot peak plantar pressure while a commercial product, a material traditionally used for plantar cover paddings, increased pressure in the region of the second–fourth Metatarsophalangeal Joint. This demonstrates the potential for auxetic materials to become the material of choice for such applications, especially since it can be further remodeled until its properties can produce a significant forefoot pressure reduction.

Cadaveric Evaluation of Dorsal Intermetatarsal Approach for Plantar Plate and Lateral Collateral Ligament Repair of the Lesser Metatarsophalangeal Joints.

Access to the plantar plate has been described using either a plantar approach or an extensive dorsal approach that required complete joint destabilization and often a metatarsal osteotomy. Clinical scenarios related to plantar plate tear vary and the pathologies in early stages are frequently limited to unilateral soft tissue structures; a less invasive operative approach may be possible. A novel approach requiring a release of only the lateral collateral ligament and the lateral half of the plantar plate is presented in this cadaver model; the extent of joint exposure possible is described. The ability to place a secure suture through the lateral collateral ligament and the plantar plate was analyzed. Nine fresh-frozen cadaveric specimens were dissected in a randomized fashion across the second to fourth metatarsophalangeal joints through the intermetatarsal space dorsally. Under distraction, soft tissue was sequentially released, including dorsal capsule, lateral collateral ligament, and the lateral half of the plantar plate. Integrity of the extensor tendons, deep transverse intermetatarsal ligament, proximal attachment of the plantar plate, and osseous structures was carefully preserved. The joint exposure was quantified after each step with sizing rods. Using a suture passer, 2-0 nonabsorbable braided sutures were passed into the lateral collateral ligament and the plantar plate, and the construct strength was measured using a tensiometer. Progressive increase in mean joint exposure was noted after each step of soft tissue release with the final exposure of 6 mm after release of the lateral half of the plantar plate. Joint exposures after a capsulotomy and a lateral collateral release were 3 mm and 4 mm, respectively. Under distraction, the unilateral release of soft tissue created a lateral opening of the joint while the proximal phalangeal base adducted and medially deviated. Successful suture passage was noted in all specimens that could sustain a minimum tension of 25 N without a catastrophic failure. There was no statistically significant correlation with age, sex, foot length, and rays of the specimens when joint exposure was considered. The dorsal intermetatarsal approach appeared to be feasible for access to the lateral collateral ligament and the lateral half of the plantar plate. The average joint exposure of 6 mm allowed a quality suture passage by a suture passer in both structures in all specimens without the need of a metatarsal osteotomy. This operative approach may be appropriate for early stages plantar plate tear when only lateral soft tissue repair is needed. This technique should not preclude conversion to a more extensile operative approach or an additional metatarsal osteotomy if needed. Applicability of this operative approach in cases with more advanced pathologies or involving only medial soft tissue structures requires further studies.

Plantar Plate Repair for Lesser Metatarsophalangeal Joint Instability.

Lesser metatarsophalangeal (MTP) joint instability is a common cause of forefoot pain. Advances in operative technique and instrumentation have made it possible to anatomically treat plantar plate tears through a dorsal approach. Our goal was to evaluate the subjective, functional, and radiographic outcomes of plantar plate repair (PPR) from a dorsal approach. A prospective case series was performed evaluating the results of PPR in 97 feet with 138 plantar plate tears. Patients underwent PPR from a dorsal approach with a Weil osteotomy. We followed patients at regular intervals for 12 months and collected data preoperatively and postoperatively with respect to visual analog scale (VAS) scores, MTP range of motion (ROM), paper pull-out test, American Orthopaedic Foot & Ankle Society (AOFAS) scores, satisfaction, and radiographic measures. Eighty percent of patients scored "good" to "excellent" satisfaction scores at 12 months. The mean VAS pain score preoperatively was 5.4/10, and postoperatively was 1.5/10. The mean AOFAS scores increased from 49 to 81 points following surgery. The mean MTP ROM preoperatively was 43 degrees and postoperatively 31 degrees. Forty-two percent of toes passed the paper pull out test prior to surgery and 54% at 12 months. Mean metatarsal shortening was 2.4/3.1/1.2 mm for the second, third, and fourth metatarsals, respectively. The mean MTP joint angles preoperatively were 2/4.9/-1.3 degrees and postoperatively were 7.4/9.6/0.2 degrees, respectively, for the second, third, and fourth MTP joints. We found that the plantar plate could be repaired through a dorsal approach with reliable outcomes. PPR was a viable option to anatomically restore the ligamentous support in the unstable lesser MTP joint. Level IV, retrospective case series.

The Applicability of Plantar Padding in Reducing Peak Plantar Pressure in the Forefeet of Healthy AdultsImplications for the Foot at Risk.

We investigated the effectiveness and durability of two types of plantar padding, the plantar metatarsal pad and the single wing plantar cover, which are commonly used for reducing forefoot plantar pressures. Mean peak plantar pressure and impulse at the hallux and at the first, second, third, and fourth metatarsophalangeal joints across both feet were recorded using the two-step method in 18 individuals with normal asymptomatic feet. Plantar paddings were retained for 5 days, and their durability and effectiveness were assessed by repeating the foot plantar measurement at baseline and after 3 and 5 days. The single wing plantar cover devised from 5-mm felt adhesive padding was effective and durable in reducing peak plantar pressure and impulse at the first metatarsophalangeal joint (P = .001 and P = .015, respectively); however, it was not found to be effective in reducing peak plantar pressure and impulse at the hallux (P = .782 and P = .845, respectively). The plantar metatarsal pad was not effective in reducing plantar forefoot pressure and impulse at the second, third, and fourth metatarsophalangeal joints (P = .310 and P = .174, respectively). These results imply limited applicability of the single wing plantar cover and the plantar metatarsal pad in reducing hallux pressure and second through fourth metatarsophalangeal joint pressure, respectively. However, the single wing plantar cover remained durable for the 5 days of the trial and was effective in reducing the peak plantar pressure and impulse underneath the first metatarsophalangeal joint.

Accurate determination of screw position in treating fifth metatarsal base fractures to shorten radiation exposure time.

Anatomical markers can help to guide lag screw placement during surgery for internal fixation of fifth metatarsal base fractures. This study aimed to identify the optimal anatomical markers and thus reduce radiation exposure. A total of 50 patients in Huashan Hospital, Shanghai, China, who underwent oblique foot radiography in the lateral position were randomly selected. The angles between the fifth metatarsal axis and cuboid articular surface were measured to determine the optimal lag screw placement relative to anatomical markers. The line connecting the styloid process of the fifth metatarsal base with the second metatarsophalangeal (MTP) joint intersected with the fifth metatarsal base fracture line at an angle of 86.85° ± 5.44°. The line connecting the fifth metatarsal base styloid with the third and fourth MTP joints intersected with the fracture line at angles of 93.28° ± 5.24° and 100.95° ± 5.00°, respectively. The proximal articular surface of the fifth metatarsal base intersected with the line connecting the styloid process of the fifth metatarsal base with the second, third and fourth MTP joints at angles of 24.02° ± 4.77°, 30.79° ± 4.53° and 38.08° ± 4.54°, respectively. The fifth metatarsal base styloid and third MTP joint can be used as anatomical markers for lag screw placement in fractures involving the fifth tarsometatarsal joint. The connection line, which is normally perpendicular to the fracture line, provides sufficient mechanical stability to facilitate accurate screw placement. The use of these anatomical markers could help to reduce unnecessary radiation exposure for patients and medical staff.

Prevalence, morphological variation and ossification of sesamoid bones of the forefoot: a retrospective radiographic study of 8,716 Chinese subjects

Background and Aim: Previous studies provided evidence of a genetic basis for the occurrence of sesamoids bone in the foot among different ethnic populations. However, information for the Chinese population has not been previously reported. Therefore, the aim of our study was to determine the distribution, morphological variation and ossification timeline of sesamoid bones of the forefoot in a large sample of the Chinese population. Methods: Antero-posterior (AP) and oblique radiographs of 4,417 left and 4,299 right feet obtained from 8,716 patients in the Hebei province of Northern China, and retrospectively examined for the presence of sesamoid bones, identified as a small oval bone plantar to each metatarsophalangeal (MTP) joint and the first interphalangeal (IP) joint. Results and Conclusions: The prevalence rate of a sesamoid bone associated with the first to fifth MTP joints and the first IP joint was 99.96%, 3.08%, 0.39%, 0.69%, 8.94%, and 59.22%, respectively. Moreover, a morphological variation in hallucal sesamoids was identified in 12.09% of feet, with variations classified into three distinct types according to bone size and the number of ossification centers. Ossification begins in the hallucal MTP and IP joints at approximately 8 years of age, with the final ossification center being evidence for the sesamoid bone of the fourth MTP joint at 28 years of age. Relevance for patients: Our study provides important anatomical data regarding the prevalence of sesamoid bones in the forefoot of a large population of Chinese adult and pediatric patients for use in clinical practice and research in forensic science and anthropology.

Lesser Metatarsal Phalangeal Joint Arthroscopy: Anatomic Description and Comparative Dissection

The aim of this article is to describe the normal arthroscopic anatomy of the lesser metatarsophalangeal (MTP) joints and compare it with that seen in open dissection in cadaveric models. We performed arthroscopic examination of 18 MTP joints of 6 normal fresh frozen feet. The second, third, and fourth MTP joints were studied because of the higher incidence of pathologic conditions found in these joints. During arthroscopy, each anatomic structure identified was named and marked with different colored sutures using straight suture needles. After the arthroscopic procedure of identification and marking, each MTP joint was dissected, and all the anatomic structures were grossly identified. With these data, the correlation between the arthroscopic and the direct visualization of a normal MTP joint was established. Considering the joint regions, we found that the examination accuracy of the medial gutter was 91%, whereas the central joint accuracy reached 100% and the accuracy of the lateral gutter was 98%. The overall arthroscopic accuracy for the lesser MTP joints was 96%. There is a high level of anatomic accuracy at the lesser MTP joint with arthroscopy. The high overall level of anatomic accuracy of lesser MTP joint arthroscopy (96%) allows us to consider this resource as a valuable tool in the diagnosis and treatment of these joints, expanding the spectrum of indications using this method.

Pinning across the Metatarsophalangeal Joint for Hammertoe Correction: Where Are We Aiming and What Is the Damage to the Metatarsal Articular Surface?

Kirschner wire (K-wire) fixation across the metatarsophalangeal joint (MTPJ) is commonly used in hammertoe repair surgery. The purpose of the present study was twofold: (1) to determine where the K-wire penetrates the metatarsal articular surface to achieve a rectus digit; and (2) to quantify the percentage of cartilage disruption to better understand the consequences of K-wire transfixation of the MTPJ. Arthrodesis was conducted on the second, third, and fourth proximal interphalangeal joints of 10 below-the-knee cadaver specimens, using a 1.6-mm K-wire. Digital alignment was confirmed with simulated weightbearing intraoperatively and radiographically. The K-wire was removed, and the MTPJ was dissected until the metatarsal head was fully exposed. The penetration point was plotted on a quadrant system with deviation noted from the epicenter. Center was defined as the point equidistant from the medial-to-lateral and superior-to-inferior edges on the distal surface of the metatarsal head, excluding the plantar condyles. Statistically significantly deviations were found in the K-wire placement from the center (35.9% ± 17.5%, p < .001), medial-to-lateral width (22.2% ± 19.2%, p < .001), and dorsal-to-plantar height (15.8% ± 25.0%, p = .002). Relative to the center, the K-wire was superior in 22 (79%), inferior in 6 (21%), medial in 22 (79%), and lateral in 6 (21%) of the cadaveric MTPJs. The mean percentage of disruption of the articular cartilage was 1.8% ± .4% and was similar for the second, third, and fourth MTPJs (p = .13) and for the left and right feet (p = .75). This information could be used to guide surgeons when they transfixate the MTPJ during hammertoe correction and might contribute to preservation of the articular cartilage.

Irreducible dislocation of the fourth metatarsophalangeal joint—a case report

Traumatic dislocation of the metatarsophalangeal joint of an isolated lesser toe is an uncommon injury. We report a patient who presented 1 day after a dorsiflexion injury of the right foot. Physical examination showed a shortened and angulated right fourth toe resulting in scissoring of his digits. X-rays of the right foot confirmed complete dislocation of the fourth metatarsophalangeal joint. After failing 4 attempts at closed reduction, an orthopedic consult was made, and he underwent surgery. Six months after the operation, he developed avascular necrosis of the fourth metatarsal head. Reduction of the metatarsophalangeal of an isolated lesser toe is difficult due to the anatomical constraints imposed by the surrounding soft tissue. Failure at reduction after a single attempt by an experienced emergency physician should prompt the need for an orthopedic consult in view of likely surgery required. Avascular necrosis of the metatarsal head can also occur as a late complication after such injury.