HISTOLOGICAL COMPARISON OF THE THIRD INTERDIGITAL NERVE IN PATIENTS WITH MORTON'S METATARSALGIA AND CONTROL PATIENTS

This study compares the histology of the plantar-digital nerve supplying the third web space in asymptomatic patients with those who have clinically diagnosed Morton's metatarsalgia. Despite several studies concentrating on the histological changes in the interdigital nerve, the relevance of these changes is a matter of contention while the exact pathological process responsible for the symptoms has not been determined. The histological findings in control patients were identical to Morton's patients with the exception of demyelination, which was more common in the Morton's group. This suggests that the characteristic nodule and fibrotic changes seen in the interdigital nerves of patients with Morton's neuroma cannot account for the symptoms and that the changes seen in the neurovascular bundle are degenerative in origin and are found in asymptomatic patients.     

Second metatarsal osteotomies for metatarsalgia: A robotic cadaveric study of the effect of osteotomy plane and metatarsal shortening on plantar pressure

Symptom relief of recalcitrant metatarsalgia can be achieved through surgical shortening of the affected metatarsal, thus decreasing plantar pressure. Theoretically an oblique metatarsal osteotomy can be oriented distal to proximal (DP) or proximal to distal (PD). We characterized the relationship between the amount of second metatarsal shortening, osteotomy plane, and plantar pressure. We hypothesized that the PD osteotomy is more effective in reducing metatarsal peak pressure and pressure time integral. We performed eight DP and eight PD second metatarsal osteotomies on eight pairs of cadaveric feet. A custom designed robotic gait simulator (RGS) generated dynamic in vitro simulations of gait. Second metatarsals were incrementally shortened, with three trials for each length. We calculated regression lines for peak pressure and pressure time integral vs. metatarsal shortening. Shortening the second metatarsal using either osteotomy significantly affected the metatarsal peak pressure and pressure time integral (first and third metatarsal increased, p < 0.01 and <0.05; second metatarsal decreased, p < 0.01). Changes in peak pressure (p = 0.0019) and pressure time integral (p = 0.0046) were more sensitive to second metatarsal shortening with the PD osteotomy than the DP osteotomy. The PD osteotomy plane reduces plantar pressure more effectively than the DP osteotomy plane. Published 2013 by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 32:385–393, 2014.     

Common disorders of the adult foot and ankle

Intricate bony and soft tissue anatomy associated with complex biomechanics can provide a significant challenge when considering the pathologies affecting the adult foot and ankle. The aim of this article is to introduce some of the clinical features and treatments for more common foot and ankle conditions.     

Plantar pressures and relative lesser metatarsal lengths in older people with and without forefoot pain

Forefoot pain is a common problem in older people. We determined whether plantar pressures during gait and the relative lengths of the lesser metatarsals differ between older people with and without plantar forefoot pain. Dynamic plantar pressure assessment during walking was undertaken using the Tekscan MatScan® system in 118 community‐dwelling older people (44 males and 74 females), mean age 74 (standard deviation = 5.9) years, 43 (36%) of whom reported current or previous plantar forefoot pain. The relative lengths of metatarsals 1–5 were determined from weightbearing X‐rays. Participants with current or previous plantar forefoot pain exhibited significantly (p = 0.032) greater peak plantar pressure under metatarsal heads 3–5 (1.93 ± 0.41 kg/cm² vs. 1.74 ± 0.48 kg/cm²). However, no differences were found in relative metatarsal lengths between the groups. These findings indicate that older people with forefoot pain generate higher peak plantar pressures under the lateral metatarsal heads when walking, but do not exhibit relatively longer lesser metatarsals. Other factors may be responsible for the observed pressure increase, such as reduced range of motion of the metatarsophalangeal joints and increased stiffness of plantar soft tissues. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 427–433, 2013     

拇外翻术后转移性跖痛症的研究进展

拇外翻术后少数患者易发生转移性跖痛症,严重影响患者工作和生活质量。熟悉并了解其发病机制和治疗方法对于转移性跖痛症的临床预防、治疗及康复均具有十分重要的指导意义。目前临床上除保守治疗外,主要采用手术治疗的方法。但因各家学术观点不同,给临床医生在选择治疗法则及术式上造成诸多困难。本文综合了国内外当前主要学术流派的观点及看法,并简要评价,针对其常见发病机制及治疗方法进行综述。     

The role of fasciae in Civinini–Morton's syndrome

This study evaluates the pathogenetic role of the perineural connective tissue and foot fasciae in Civinini–Morton's neuroma. Eleven feet (seven male, four female; mean age: 70.9 years) were dissected to analyse the anatomy of inter‐metatarsal space, particularly the dorsal and plantar fasciae and metatarsal transverse ligament (DMTL). The macrosections were prepared for microscopic analysis. Ten Civinini–Morton neuromas obtained from surgery were also analysed. Magnetic resonance images (MRIs) from 40 patients and 29 controls were compared. Dissections showed that the width of the inter‐metatarsal space is established by two fibrous structures: the dorsal foot fascia and the DMTL, which, together, connect the metatarsal bones and resist their splaying. Interosseous muscles spread out into the dorsal fascia of the foot, defining its basal tension. The common digital plantar nerve (CDPN) is encased in concentric layers of fibrous and loose connective tissue, continuous with the vascular sheath and deep foot fascia. Outside this sheath, fibroelastic septa, from DMTL to plantar fascia, and little fat lobules are present, further protecting the nerve against compressive stress. The MRI study revealed high inter‐individual variability in the forefoot structures, although only the thickness of the dorsal fascia represented a statistically significant difference between cases and controls. It was hypothesized that alterations in foot support and altered biomechanics act on the interosseous muscles, increasing the stiffness of the dorsal fascia, particularly at the points where these muscles are inserted. Chronic rigidity of this fascia increases the stiffness of the inter‐metatarsal space, leading to entrapment of the CDPN.     

Komplikationen der Tarsometatarsale I Arthrodese (modifizierte Lapidus Arthrodese)

BackgroundFirst tarsometatarsal arthrodesis, or known as modified Lapidus arthrodesis, is a powerful procedure for hallux valgus correction. Historically there have been high reported complication rates including nonunion, dorsiflexion malunion and transfer metatarsalgia, due to the high lever at the TMT I joint.MethodsThe development of new biomechanically more stable fixation methods has revolutionized the classic Lapidus arthrodesis in recent decades, so that more progressive mobilization regimens could be established.ResultsThe current clinical and radiological results of modern Lapidus arthrodesis using plate fixation confirm that nonunion rates could be drastically reduced. However, the rates of symptomatic transfer metatarsalgia remained unchanged.ConclusionOn the basis of new fixation methods, the modified Lapidus arthrodesis became a low-complication and satisfactory surgical method. The influence of first ray shortening and dorsiflexion malunion on the development of a transfer metatarsalgia has not yet been fully clarified.     

A Modified Fixation Technique for a Decompressional Shortening Osteotomy: A Retrospective Analysis

A long metatarsal and/or metatarsophalangeal joint dislocation associated with a digital contracture is a surgical challenge. Without appropriate surgical correction, the patient will be predisposed to numerous complications, including persistent subluxation or dislocation, recurrent metatarsalgia, dorsiflexory contracture of the digit, transfer lesions, and inadequate pain relief. The results of the present surgical treatment options have varied, with the most common complication being a floating toe. The purpose of our study was to introduce a decompression, shortening, lesser metatarsal osteotomy with a modified fixation technique using a T-plate and to report our results. Additionally, we have discussed trigonometric analysis of metatarsal declination and shortening. We retrospectively reviewed the outcomes of 30 consecutive patients with 33 osteotomies who had been treated surgically for pathologic features associated with a long metatarsal and varying biomechanical abnormalities. Before surgery, all the patients had been treated conservatively for a minimum of 3 months. The surgical procedure included a dorsal to plantar V-shaped shortening osteotomy of a lesser metatarsal that was fixated with a T plate. The patients were assessed radiographically and using the American Orthopaedic Foot and Ankle Society Lesser Metatarsophalangeal–Interphalangeal Scale and visual analog scale. The mean age at surgery was 53 (range 37 to 75) years, with a mean follow-up period of 9.1 (range 6 to 15.4) months. The average shortening of the metatarsal was 2.7 mm. One patient (3%) had had asymptomatic delayed union and 2 patients (6%) hypertrophic nonunion. No incidence of malunion or avascular necrosis was identified. Five cases (15.2%) of hardware failure occurred. The mean American Orthopaedic Foot and Ankle Society score was 76.7 postoperatively. The visual analog scale score had improved from 6.7 to 1.7. Of the 30 patients, 72% rated the overall surgical experience as excellent or good. In conclusion, the modified fixation technique for decompression, shortening metatarsal osteotomy using a T plate is a viable option when choosing a procedure to address a long, prominent metatarsal and/or digital contracture at the metatarsophalangeal joint and results in a low incidence of floating toe complications.     

Corticosteroid Injection for Morton's Interdigital Neuroma: A Systematic Review

BackgroudThis review aimed to evaluate the effects of corticosteroid injections on Morton''s neuroma using an algorithmic approach to assess the methodological quality of reported studies using a structured critical framework.MethodsSeveral electronic databases were searched for articles published until April 2020 that evaluated the outcomes of corticosteroid injections in patients diagnosed with Morton''s neuroma. Data search, extraction, analysis, and quality assessments were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). guidelines, and clinical outcomes were evaluated using various outcome measures.ResultsWith 3–12 months of follow-up, corticosteroid injections provided satisfactory outcomes according to Johnson satisfaction scores except in two studies. Visual analog scale scores showed maximal pain reduction between 1 week and 3 months after injection. We found that 140 subjects out of 469 (29.85%) eventually underwent surgery after receiving corticosteroid injections due to persistent pain.ConclusionsCorticosteroid injections showed a satisfactory clinical outcome in patients with Morton''s interdigital neuroma although almost 30% of the included subjects eventually underwent operative treatment. Our recommendation for future research includes using more objective outcome parameters, such as foot and ankle outcome scores or foot and ankle ability measures. Moreover, studies on the safety and effectiveness of multiple injections at the same site are highly necessary.