REVIEW ARTICLE |
https://doi.org/10.5005/jp-journals-10040-1318 |
Lesser Metatarsophalangeal Joints Instability: A Comprehensive Literature Review
1Department of Orthopedic Surgery, Ain Shams University Hospitals, Cairo, Egypt; Department of Trauma and Orthopaedics, University Hospital of Southampton NHS Foundation Trust, Southampton, United Kingdom
2Department of Trauma and Orthopaedics, University Hospital of Southampton NHS Foundation Trust, Southampton, United Kingdom
Corresponding Author: Sherif F Ahmed Kamel, Department of Orthopedic Surgery, Ain Shams University Hospitals, Cairo, Egypt; Department of Trauma and Orthopaedics, University Hospital of Southampton NHS Foundation Trust, Southampton, United Kingdom, Phone: +447442212290, e-mail: tumorman2011@gmail.com
Received on: 25 April 2023; Accepted on: 21 June 2023; Published on: 20 October 2023
ABSTRACT
Aim and background: Lesser metatarsophalangeal instability can result in forefoot pain and deformity. This represents a relatively common problem. Despite this, there has been little information about the main causes and management of this condition in the literature. The aim of this article is to review the current literature about the management of this problem and to highlight the role of plantar plate pathologies in pathogenesis. We also propose a management algorithm.
Materials and methods: A comprehensive literature search was performed, with no time limit through PubMed, Medline, and Embase. The article abstracts were reviewed, and those that were not involving lesser metatarsophalangeal joints (MTPJs), nor in English were excluded.
Results: A total of 313 articles were found by the search. After the removal of duplicates and exclusion as per methodology, 186 articles remained. We describe the anatomy of the plantar plate, clinical presentation, investigations, classification, and treatment options. We discussed the various outcome measures of different studies on this topic up to date.
Conclusion: Plantar plate tears play a pivotal role in lesser metatarsophalangeal instability. Conservative management is the mainstay of initial management. If this fails, then surgical treatment is indicated.
Clinical significance: We provided an up-to-date comprehensive literature review of this relatively common condition that is not fully understood.
How to cite this article: Ahmed Kamel SF, Koç T. Lesser Metatarsophalangeal Joints Instability: A Comprehensive Literature Review. J Foot Ankle Surg (Asia-Pacific) 2023;10(4):166–174.
Source of support: Nil
Conflict of interest: None
Keywords: Crossover deformity, Flexor tendon transfer, Lesser metatarsophalangeal joint instability, Metatarsalgia, Plantar plate, Plantar plate injury, Plantar plate repair
INTRODUCTION
Forefoot problems affect many people and can be debilitating, on either occupational or leisure aspects.1 Around 40 years ago, deformities at the lesser metatarsophalangeal joint (MTPJ) were not fully understood.1 In 1987, Coughlin described the term “crossover second toe deformity.”2 Around 2s ago, Deland and Sung systematically examined patients with unilateral crossover toe deformity and compared it to the normal contralateral foot.3 They found multiple pathologies, including medial displacement of the flexor tendons and plantar plate, plantar plate deformity, contracture of the medial collateral ligament, and rupture of the lateral collateral ligament of the toes. Around 1s ago, Coughlin et al. through cadaveric studies put forward that the causative pathology was a tear in the plantar capsule of the MTPJ, known later as the plantar plate.4,5
The aim of this article is to review the current literature about anatomy and pathology, clinical presentations, and management options of the lesser MTPJ instability. A management algorithm (Figs 123456789) is proposed for this relatively common condition.
Fig. 1: Descriptive anatomical and histological data visualized in a schematic 3D drawing of the plantar plate. Legend: ACL, accessory collateral ligament; DTML, deep transverse metatarsal ligament; EDL+ EDB, extensor digitorum longus/brevis; EH, extensor hood; FDL + FDB, flexor digitorum longus/brevis; FS, flexor sheath; MT, metatarsal; PCL, proper collateral ligament; Pr Ph, proximal phalanx13
Fig. 2: Photograph of the metatarsal head with plantar plate reflected toward the bottom left and proximal plantar plate attachment visible with notable invagination of articular surface at the insertion site with pedicle labeled with a black arrow14
Fig. 3: Drawer test: the proximal phalanx is positioned at 25° of dorsiflexion then dorsal translation stress is applied to the proximal phalanx40
Figs 4A and B: (A) Paper pull-out test: placing a piece of paper under the second toe, and then asking the patient is bend the toe to grip the paper against the floor. The examiner then pulls the paper and if the patient is unable to keep the paper from being pulled from beneath the toe without tearing, the test is positive; (B) In B, the test is negative40
Figs 5A and B: A and B: Tapping is done to maintain 10° plantarflexion (A) From dorsal; (B) From plantar aspects8
Fig. 6: Budin splint: a flat sole pad with an elastic band wrapped around the affected toe55
Fig. 7: Clinical photograph of lesser MTPJ portals for arthroscopy32
Fig. 8: Flowchart of surgical algorithm
Fig. 9: Flowchart of proposed surgical approach
Epidemiology
Peck et al. studied 156 patients with lesser MTPJ instability and synovitis and found that these were present in 26% of patients attending the clinic with forefoot pain.6 Around 82% of patients were middle-aged women with a median age of 56.5 years.7 However, there was a secondary group, younger male athletes, representing 26–79% of cases.7,8 Lesser MTPJ instability is often bilateral, usually affects the second MTPJ but can also affect the third and/fourth MTPJs, can affect single or multiples MTPJs, and is frequently associated with lesser toe deformities such as hammer toe or cross-over toe.8
MATERIALS AND METHODS
A comprehensive literature search was performed, with no time limit to maximize the pool of studies available for review. The databases used were PubMed, Medline, and Embase. The terms used for searching were—“lesser metatarsophalangeal instability*,” “MTPJs,” “instab*,” “joint instability,” and “lesser.” The article abstracts were reviewed and those that were not involving lesser MTPJs, nor had English translations if original articles were not in English were excluded.
RESULTS
A total of 313 articles were found by the search. After the removal of duplicates and exclusion as per methodology, 186 articles remained.
Anatomy
The plantar plate is a flexible, firm, broad, ribbon-like disc that measures 19 × 2 mm.9,10 It originates from the periosteum of the metatarsal with its periphery stronger and thicker compared to its central portion.10 It inserts directly into the bone along the entire width of the plantar surface of the proximal phalanx with longitudinal and interwoven collagen bundles with multiple interdigitations.11,13 The flexor pulley is a distinct thickening of the tendon sheath that is adherent or invested into the borders of the plantar plate. Its plantar surface is smooth and grooved at its outer borders to allow for frictionless gliding of the flexor tendons.9
The plantar plate is a thick fibrocartilaginous tissue, which is composed mainly of type I (75%) and type II collagen bundles separated by loose connective tissue, chondrocytes, and fibroblasts.9 The bundles are mainly oriented longitudinally except the plantar one-third, where collagen fibers are orientated transversely in line with the deep transverse intermetatarsal ligament (DTML). The DTML connects the plantar plate to adjacent plantar plates of the lesser toes and in the case of the medial aspect of the second MTPJ plantar plate, the lateral sesamoid of the first MTPJ.9
Park et al.14 studied six cadaveric specimens and found that the plantar plate origin consists of a stout fibrous pedicle distinct from the surrounding synovial-type tissue that firmly anchors the plantar plate to the metatarsal. Imaging of 16 fresh frozen cadaveric specimens using nano-computed tomography showed that 63.5% of the vascular supply to the proximal portion of the plantar plate entered from the metatarsal pedicle and the rest from the plantar fascia.
The function of the plantar plate is a duality of resistance to forces during weight-bearing and joint stability.15,16 The plantar plate provides cushioning to the MTPJ during weight-bearing. It is the primary restraint against sagittal tensile stresses by providing passive resistance to dorsiflexion and active resistance through the peripheral attachment of the intrinsic muscles of the foot. The collateral ligaments contribute to both transverse and longitudinal stability.17,4
Etiology
The exact cause of lesser MTPJ instability is unclear in the current literature despite being a common forefoot pathology.18 However, it is believed that there are several anatomical and biomechanical factors that may contribute to the pathology.19
High heels, first-ray instability, and “excessive” lesser metatarsal length have all been described in the literature.3,20-22 Kaz and Coughlin found a correlation between cross-toe deformity and hallux valgus, but others did not find a strong correlation of plantar plate disruption with the length of the second metatarsal, as only 44% of their study population had a long second metatarsal.21,23
All the above factors or other idiopathic factors may cause synovitis and capsulitis in the lesser MTPJ.24,25 Chronic injury to the plantar plate causes attrition, elongation, attenuation, and eventually rupture of the plantar plate.3,12,26 Subsequently, the dynamic stabilizing muscle balance between intrinsics and extrinsics is lost and the flexors move dorsomedially leading to progressive deformity.3 Plantar plate damage is likely to play a pivotal role in lesser MTPJ instability, according to several cadaveric and biomechanical studies.26-28
Clinical Presentation
A detailed history is crucial for diagnosis. Gradual plantar pain, localized to the proximal phalanx base and often during the third rocker phase of gait is typically the main complaint of early lesser MTP instability.29 However, this may not be present and lead to misdiagnosis and delay of management.19 Later, deformity, both sagittal and coronal, as well as plantar swelling and Morton’s neuroma-like symptoms may appear.3-5,15,30 A history of specific trauma is unlikely but may be associated with acute plantar plate tear or rupture. Enquiries about multiple steroid injections, systemic conditions like autoimmune arthropathies, neurologic or congenital conditions should be included in the assessment.31
Systematic examination focussing on the forefoot but incorporating salient aspects of the midfoot and hindfoot is recommended.32 While standing, a comparison can be made with the opposite foot and unaffected toes. Medial deviation of the toe(s), hammer toe, or a toe gap between adjacent toes are common features.7,4,33 Dorsiflexion and crossover deformity are advanced features.21,16,33 Hallux valgus or varus should also be noted as it may be a cause of MTP stability and should be addressed accordingly during treatment.33 Plantar hyperkeratotic lesions of forefoot overload tend to be singular and cover a large area or are more focalized under individual metatarsal heads in a disease affecting only one MTPJ. Systematic palpation for tenderness should be done, specifically the plantar plate insertion and underneath the metatarsal head. Tenderness in the intermetatarsal space due to MTPJ inflammation or intermetatarsal bursa can be interpreted as Morton’s neuroma, whereas Mulder’s test may result in pain without a “click.” Both conditions can coexist in 20% of cases,31,34 so local anesthetic injections can be used for diagnosis.31 The flexibility of the deformity is important to assess as it can affect the treatment.31 The Drawer test (also known as the Lachman test) was first described by Thompson and Hamilton (Fig. 3). A positive test is described as 50% joint subluxation in the sagittal plane.21,30 The Lachman test is for lesser MTPJ instability and has high sensitivity (80.6%), and specificity (99.8%) preoperatively and postoperatively.21,30,35 The “paper pull-out” test was described by Bouché and Heit, as a dynamic way to measure the degree of the digit purchase (Fig. 4).36 A positive test can suggest loss of intrinsic stability and function and is also important postoperatively as it is the common finding with the post-operative complication of “floating toe.”37-39 Klein et al. studied 90 patients and found that a positive drawer sign, with a gradual onset of pain and pain localized to the metatarsal head, was present in 95% of patients with a plantar plate tear.31,35
Classification
Classification systems are clinically useful as they may guide treatment. The most commonly used clinical and anatomic classification systems have been devised by Nery et al.30 and Coughlin et al.5 (Table 1). Grade III tears are considered the most prevalent, representing almost 50%.
| Grade | Anatomy | Alignment | Physical examination |
|---|---|---|---|
| 0 | Plantar plate ± capsular attenuation | No instability | MTPJ pain, MTPJ swelling, reduced toe purchase, and negative drawer |
| I | Transverse distal tear <50% (width) or midsubstance tear <50% | Mild deformity—webspace deviation | MTPJ pain, MTPJ swelling, loss of toe purchase, and mild positive drawer (<50% subluxation) |
| II | Transverse distal tear >50% (width) or midsubstance tear >50% | Moderate deformity—toe elevation and coronal deviation | MTPJ pain, MTPJ swelling (less), loss of toe purchase, and moderate positive drawer (>50% subluxation) |
| III | Extensive tear (transverse or longitudinal or V tear or T tear) ± collateral ligament involvement | Severe deformity—toe elevation, overlap, and flexible hammertoe | MTPJ and toe pain, MTPJ swelling (little), loss of toe purchase, very positive drawer (dislocate), and flexible hammertoe |
| IV | Cruciform tear with buttonholing of MT head (MTPJ dislocation) | MTPJ dislocation—crossover, fixed hammertoe | MTPJ and toe pain, MTPJ swelling (little or no), loss of toe purchase, dislocated MTPJ, and fixed hammertoe |
Imaging
Imaging may be used in early stages, or for preoperative planning. Weight-bearing orthogonal and medial oblique views of the foot are important to assess associated hallux, midfoot or hindfoot deformity, the metatarsal cascade, MTPJ congruity, and associated arthritis or osteonecrosis.40,41 Several studies showed that magnetic resonance imaging (MRI) is considered highly sensitive and specific in determining plantar plate pathology.30,42,43 Ultrasonography may be used for confirmation of the diagnosis or alternative pathology like Morton’s neuroma. Although ultrasonography is operator-dependent, some studies showed that it was more sensitive than MRI (92 vs 74%) in experienced hands, while MRI was more specific (100 vs 25%) when done at 3.5 mm slice cuts.42,44,45 The presence of pericapsular fibrosis around the base of the proximal phalanx that extends into the intermetatarsal space (pseudoneuroma sign), and the plantar plate-proximal phalanx distance were independent predictors of plantar plate tears, according to Yamada et al.46
MANAGEMENT
Nonoperative
Conservative treatment is the primary line of management, on a case-by-case basis, especially in the early stages (Coughlin 0–II).22,27 Several modalities were described in the literature including footwear modifications, insoles, taping, and steroid injections. Patient compliance is crucial to the success of the treatment, which could be lengthy.47,48 The acute stage may take from 1 week up to 6 months.49-51 The whole treatment may take up to 1 year.49,50 Athletes could take longer periods to return to competitive sports.52
In the acute stage, nonsteroidal anti-inflammatory medications (NSAIDs) and offloading Darco, rocker-bottom, or stiff-soled shoes may help.12,13,22,49-51 Weight-bearing sports should be avoided until settlement of the acute symptoms and the drawer test turns negative.49-51
Taping of the affected toe, as in Figure 5, with or without Darco Peg-Assist, can help to reduce the pain by providing sagittal stability in early stages and for short periods only to avoid ulceration and chronic swelling.24,53 A budin splint can be used as an alternative (Fig. 6).49,51,52
Accommodative wide-toe box shoes with a soft upper material can be used to reduce mechanical irritation. Accommodative insoles with metatarsal pads can help in stress distribution in the third rocker of gait and hence reduce the pain in the affected toe.4,24,54
Finally, selective steroid injections should be used cautiously to avoid fat pad atrophy and plantar plate rupture.4,24,54 Following injection, taping, and restriction of weight-bearing for 6 weeks is recommended by some authors.22,55
Operative
Operative treatment is indicated if nonoperative measures fail.6,25,37,39,55,56 Techniques described are soft tissue, bony, or combined procedures. Soft tissue procedures include plantar plate repair, MTPJ collateral ligament balancing, or flexor-to-extensor tendon transfer. Bony procedures include distal metatarsal osteotomy or MTPJ arthrodesis. During the procedure, other relevant deformities should also be addressed (e.g., hallux valgus, hammer toe). These procedures were described as either open, percutaneous, or arthroscopic surgery. The goals of surgery are to improve plantar pain, correct malalignment and restore MTPJ stability.57
Plantar Plate Repair
Direct plantar plate repair could be done through a dorsal.12,30,56 or plantar approach,36,58 either alone or in conjunction with other procedures.58 A recent systematic review and meta-analysis reviewed different plantar plate repairs, including dorsal approach with or without distal metatarsal osteotomy, plantar approach, or dual approach, besides, suture button, and arthroscopic techniques.59
Dorsal approaches are more commonly used than plantar approaches.59 A dorsal longitudinal incision is made lateral to the extensor tendons of the toe. The tendons are then retracted laterally and the MTPJ collateral ligaments are exposed. The collaterals are released from the base of the proximal phalanx but preserved on the metatarsal head to protect the blood supply. A McGlamry elevator is used to release the plantar plate from the metatarsal head to allow for visualization and mobilization. If an associated Weil osteotomy is performed, this is done and temporarily held with K-wire if desired. Definitive fixation of the Weil osteotomy should usually be done after soft tissue releases but before fixation of soft tissue repairs. Joint distraction is performed using a small joint distractor, then the tear is inspected and graded. If repair is decided, then the plantar plate is released from the base of the proximal phalanx distally, debrided, and a horizontal mattress suture is then placed in the distal part using a small, curved needle or other commercial devices like a mini-scorpion (Arthrex, Naples, FL). Medial and lateral tunnels are made through the base of the proximal phalanx from the dorsal aspect using a 1.6 mm K-wire. The suture is then passed using a suture passer from plantar to dorsal. The distractor is then removed and the suture is firmly tied with the toe held in 10–20° of plantarflexion. Collateral ligament release on the concavity with collateral ligament repair on the convexity of an MTPJ deformity in the medial/lateral plane can be performed.17,31 Wound closure is performed and dressings are applied to immobilize the toe in 10–20° of plantar flexion. Postoperative rehabilitation is with a postoperative shoe to allow heel weight-bearing for 6 weeks with continued taping/splinting of the operated toe in 10–20° of plantar flexion.31,53,60
The plantar approach was described by McAllister and Hyer.61 Bony procedures are performed first if necessary through a dorsal approach, then an 18G needle is placed through the dorsal wound into the MTPJ to mark the plantar incision. If no dorsal approach is required, an incision is placed under web space and the neurovascular bundle on either side of the MTPJ is identified and protected. The flexor tendon is exposed, the sheath is opened and a self-retaining retractor is placed to visualize the plantar plate. The tear is exposed and repaired using suture anchors, or transosseous fixation, using No. 0 vicryl sutures in a pants-over-vest fashion.31,61,62
Arthroscopic procedures were also described. A toe distractor is applied, then a 1.9 mm 30° arthroscope is used to visualize the joint utilizing dorsomedial and dorsolateral portals 4–5 mm medial and lateral to the extensor digitorum longus (EDL) tendon, respectively at the level or slightly distal to the MTPJ. The joint is distended using 2 mL saline. A 100% continuous flow of saline at 30 mm Hg pressure is used to avoid overdistention-induced neurapraxia. The medial and lateral gutters and the central joint are visualized to assess the articular cartilage, collateral ligaments, and the medial and lateral bundles of the plantar plate. A 2.0 mm shaver, small radiofrequency ablator, awls, curettes, or probes could be used for the management of intraarticular lesions.63-65
In arthroscopic-assisted double plantar plate tenodesis,63 No. 1 polydioxanone suture is passed through the plantar plate using a straight needle under arthroscopic visualization. A proximal incision is then made dorsally over the metatarsal shaft and the sutures are retrieved using a hemostat deep to the flexor tendons, then tenodesed to the extensor digitorum brevis (EDB). In arthroscopic direct plantar plate repair, the plantar plate is released from the proximal phalanx via the shaver or a beaver blade under arthroscopic guidance, then a horizontal mattress suture is passed into the plantar plate using the Arthrex Viper (Arthrex, Naples, FL). Transosseous fixation is done as before, with a small dorsal incision to ensure that the sutures are tied on bone and that the EDL tendon is not entrapped.31
Metatarsal Osteotomy
Weil osteotomy is an intraarticular, oblique osteotomy and is the most commonly used metatarsal osteotomy in the context of the management of lesser MTPJ instability. However, transverse shortening osteotomies (distal metatarsal, metatarsal shaft, or basal) were also described.66,70 In Weil osteotomy, a cut is made from distal dorsal to proximal plantar, starting just distal to the dorsal termination of the articular surface of the metatarsal head, parallel to the plantar surface of the foot, to allow for shortening without depression. It is important to angle the osteotomy more plantar when performed on more lateral metatarsals due to changes in metatarsal declination along the sagittal cascade. Once the osteotomy is complete, the metatarsal is shortened to the desired level avoiding over-shortening which could lead to adjacent iatrogenic transfer metatarsalgia. After preliminary fixation with a K-wire if desired, an image intensifier can be used to verify position before the osteotomy is fixed with one or two mini-screws.55,66-71
A recent study by Sallent et al.72 looked at the utilization of open Weil osteotomy and distal metatarsal metaphyseal osteotomy to medialize the metatarsal head without soft tissue procedures in divergent second and third toes. They found that this bony realignment allowed soft tissue rebalancing to restore normal alignment in the coronal and sagittal planes.
Tendon Transfer
Traditionally, a flexor-to-extensor tendon transfer is performed using single or two incisions.73 In the single incision technique, a dorsal incision is used, the extensor hood is split medially and laterally, then the EDB tendon is transected and/or the EDL lengthened. The MTPJ is sequentially released and the flexor digitorum longus (FDL) tendon is localized and then split into medial and lateral parts, which are passed dorsally and sutured to EDL distally on the dorsum of the proximal phalanx with nonabsorbable sutures, while the MTPJ is held reduced and the toe plantarflexed 10–20°.74
Flexor tendon tenodesis was shown to restore about 50% of dorsal stability of MTPJ according to a recent cadaveric study.73 Finally, EDB can be used to reconstruct the collateral ligaments through bony tunnels, via either dorsal or plantar approaches using 3 × 8 mm interference screws (Arthrex, Naples, FL).17,31
Other Procedures
Metatarsophalangeal joints (MTPJs) arthrodesis was described as a salvage procedure with satisfactory results, especially with prior or concomitant hallux MTPJ fusion.75 This is usually performed via a dorsolinear incision and fixed using a dorsal locking plate with mini-screws or two crossed screws in neutral rotation, neutral valgus/varus, and 5–15° of dorsiflexion, depending on the toe cascade.75
In the elderly, especially unfit patients, amputation of the affected digit at the level of MTPJ can be considered in severe cases.76 This can be performed utilizing a fish-mouth incision around the plantar aspect of the middle part of the proximal phalanx. Advantages are quicker postoperative recovery without the requirement for prolonged immobilization.
DISCUSSION
Despite lesser MTPJ instability being a relatively common pathology, its etiology is not fully understood. The plantar plate is thought to play a central role in the initiation of lesser MTPJ instability, leading to the flexors and extensors becoming potential deforming forces, leading to subluxation and subsequently dislocation of the lesser MTPJ. In this article, we discussed the anatomy of the plantar plate and associated soft tissue structures, from cadaveric to imaging studies.
A thorough clinical assessment is necessary with two special tests, a drawer test, and a paper pull-out test described. Radiographs, MRIs, and ultrasound scans can be useful in confirming the diagnosis and in assessing concomitant other pathology. The plantar plate tears were classified by different authors into grades 0–IV.
Conservative management is thought to be the initial treatment. Peck et al.6 studied 154 patients with lesser MTPJ instability, with 99 cases treated conservatively and followed up for 65 months with a 79% follow-up rate. Conservatively treated patients reported a 52% satisfaction rate in contrast to 66% in surgically treated patients. Around 24 patients from the operative group were managed conservatively first. In this subgroup, the satisfaction rate was 71%.
Surgical techniques are highly variable. Plantar plate repair has recently increased in popularity accompanied by studies to support its efficacy and some commercially available repair systems. A recent systematic review and metanalysis61 including 12 studies with 537 plantar plate tears found marked improvement in the functional and pain scores concluding that direct dorsal repair showed a predictable level of improvement with follow-up to 2 years.59 The authors suggested that Weil osteotomy was a critical part of the repair that contributes to the success of the procedure. Limitations were that the reviewed studies were mainly level 4 evidence, lacking control groups with only two studies included utilizing a plantar approach.
One of the earliest studies about plantar plate repair and Weil osteotomy was the retrospective study by Gregg et al.58 of 35 cases with a 74% patient satisfaction rate. However, Jastifer and Coughlin77 concluded that Weil osteotomy was not necessary in their cadaveric study. Flint et al.38 studied 138 procedures of dorsal plantar plate repair and they reported 80% good and excellent satisfaction scores at 1 year follow-up. The authors drew attention to significant MTPJ stiffness postoperatively, however only six had residual positive drawer tests.
The main concern about the plantar approach for plantar repair is wound complications, plantar scar pain, and the lack of exposure to concomitant procedures such as Weil osteotomy. Sharpe et al.,62 described it as safe and effective, as they retrospectively studied 204 plantar plate repairs in 185 patients. They reported a complication rate of 15% including superficial infection (6.8%, especially in smokers, or nine), painful scar (8.3%), or reoperations for deformity or instability (1.4%). The odds of complications were not affected by the method of repair, diabetes, neuropathy, or associated ipsilateral procedures.78-80
Arthroscopic repair may be attractive due to smaller incisions, quicker recovery, less morbidity, and the diagnostic role of intraarticular lesions. Lui and LiYeung63 used arthroscopically-assisted double plantar repair tenodesis for 10 cases, and they found full correction with no recurrence at the final follow-up, however, two cases had residual pain, which was 80% less than preoperatively.
Metatarsal osteotomy has a variable success rate of 57–100%.68 Possible complications include transfer metatarsalgia, due to excessive shortening, nonunion and hardware failure, or malunion.63,65 Weil osteotomy is the most popular, due to its oblique nature that allows controlled shortening, stable fixation, big surface area for bony union, and low risk of osteonecrosis and arthritis.69,78 Fleischer et al.71 studied 86 patients with 21 cases of isolated Weil metatarsal osteotomy (WMO) and 65 cases of Weil osteotomy and plantar plate repair [WMO + Plantar plate repair (PPR)], for a 3.5-year follow-up. They found better functional results, pain scores, and quality of life in those who had WMO + PPR. They recommended plantar plate repair should be attempted with shortening osteotomy, regardless of the grade of plantar plate tear.72
Donegan et al.79 described FDL reinforcement of the plantar plate in ten patients with an average follow-up of 3.7 months. There was no recurrence but two cases had superficial infection that settled on oral antibiotics and one had broken hardware that was removed. Boyer and DeOrio80 studied 79 toes in 38 patients who had flexor to extensor tendon transfer, retrospectively for a mean follow-up of 33 months, and they found a satisfaction rate of 89% with few complications.
Hollawell et al.75 reported on the management of five toes of four patients with lesser MTPJ instability utilizing MTPJ arthrodesis. After a mean follow-up of 21 (range 15–24) months. One patient had minor wound dehiscence that was managed conservatively and another patient had nonunion requiring revision arthrodesis. All patients achieved clinical and radiographic union, with a mean time to radiographic union of 16.4 weeks.
Gallentine and DeOrio,76 retrospectively studied 12 patients (17 toes) with MTPJ amputation with a mean age of 78 (range 72–86) years. All patients were satisfied, 75% had activity improvement, and two-thirds had a valgus drift of the big toe which was not clinically significant.
Management Algorithm
CONCLUSION
Lesser MTPJ instability is a relatively common condition and plantar plate tears are the main etiology. Conservative management is the mainstay of initial treatment. If this fails, then surgical treatment is needed. There is a paucity of literature on the comparison between the different surgical approaches. A randomized controlled trial with longer follow-up is recommended to establish the difference in the outcomes of matched populations.
Clinical Significance
The clinical significance of this article is that it provided a comprehensive date literature review of this common pathology which is not fully understood.
ORCID
Sherif F Ahmed Kamel https://orcid.org/0000-0001-7164-336X
Togay Koç https://orcid.org/0009-0002-1570-0854
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