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Lesser toe deformities

64 citationsUpdated Sep 2026

Overview

The management of lesser toe deformities requires a comprehensive understanding of normal anatomy and biomechanics to address common adult deformities and apply evidence-based algorithms [1]. Surgical intervention ranges from percutaneous forefoot techniques, which offer theoretical advantages of lower morbidity and faster recovery but demand specific equipment and a lengthy learning curve [3], to arthroscopic-assisted correction via plantar plate tenodesis that facilitates early toe mobilization and minimizes the risk of stiffness [4]. For rheumatoid forefoot deformity, a novel combination of modified scarf osteotomy for the great toe and modified metatarsal shortening offset osteotomy for the lesser toes significantly improves clinical and radiological outcomes [11]. Additionally, distal metatarsal osteotomy by minimal invasive surgery is considered a safe and effective procedure for metatarsalgias of the lesser rays [19].

Operative decision-making must account for specific procedural risks and outcomes. Postoperative ischemia is a rare but immediate complication, particularly associated with revision procedures and active smokers [9]. The performance of associated tenotomies to incomplete phalanx osteotomies is associated with worse clinical outcomes, higher complication rates, and longer recovery times compared to similar forefoot surgeries without tenotomies [29]. Conversely, reduction of the PIP joint using an intramedullary nitinol implant is a good option with few complications, though it carries a high rate of arthrodesis [62].

Anatomy & Pathophysiology

Etiology and Causes

Lesser toe deformities arise from alterations in normal anatomy that create an imbalance between intrinsic and extrinsic muscles [13]. Contributing factors include improper shoe wear, trauma, genetics, inflammatory arthritis, and neuromuscular and metabolic diseases [13]. In bunionette deformity, friction between the bony prominence, soft tissue, and constrictive footwear leads to keratosis, inflammation, pain, and ulceration [38]. Cavus foot typically results from muscle imbalance in a growing foot [48]. While intrinsic muscle weakness is a major cause, weakness of the peroneal or anterior tibialis muscles is also implicated [48]. Cavus foot is rarely found in the absence of an underlying neuromuscular condition [48].

Musculoskeletal Anatomy

The extensor digitorum longus originates from the tibia and fibula and inserts into the middle and distal phalanx of the lesser toes [50]. It is innervated by the deep peroneal nerve [50] and acts to dorsiflex the toes [50]. The flexor digitorum longus originates from the tibia and inserts into the distal lesser phalanges [50]. It is innervated by the tibial nerve [50] and acts to plantar flex the lesser toes [50]. Detailed anatomical descriptions note that the extensor digitorum longus originates from the tibial condyle and fibula, inserting into the middle and distal phalanges of the toes [75]. It is innervated by the deep peroneal nerve (L5) [75] and functions to dorsiflex and extend the toes [75]. The flexor digitorum longus originates from the tibia and inserts into the distal phalanges of the second to fifth toes [75]. It is innervated by the tibial nerve (S1, S2) [75] and acts to plantar flex the toes and foot [75]. The extensor digitorum longus is the only dorsal intrinsic muscle of the foot [78]. The extensor digitorum brevis is innervated by the lateral terminal branch of the deep peroneal nerve [78].

The tarsal tunnel is a fibroosseous tunnel within the posteromedial ankle and hindfoot containing the tibial nerve, posterior tibial artery, accompanying veins, posterior tibial tendon, flexor digitorum longus, and flexor hallucis longus tendons [68]. The flexor retinaculum acts as the roof of the tarsal tunnel, extending from the medial malleolus to the medial side of the calcaneal tuberosity [68]. The floor of the tarsal tunnel is formed by the medial distal tibia, talus, and calcaneus [68]. The tibial nerve divides into three terminal branches before reaching the foot: the medial calcaneal nerve, lateral plantar nerve, and medial plantar nerve [68]. The medial plantar nerve innervates the abductor hallucis and forms common digital nerves that terminate in the first, second, and third web spaces [68]. The lateral plantar nerve supplies motor branches to the intrinsic muscles of the foot [68].

Vascular anatomy includes the dorsalis pedis artery, which passes deep under the inferior extensor retinaculum and lies between the tendons of the extensor hallucis longus medially and the extensor digitorum longus laterally [71]. The deep peroneal nerve lies immediately lateral to the dorsalis pedis artery as it passes anterior to the ankle joint [71]. The first dorsal metatarsal artery is the continuation of the dorsalis pedis artery and runs distally on the dorsal surface of the first dorsal interosseous muscle [71]. This artery may lie superficial to or within the substance of the first dorsal interosseous muscle in 78% to 88% of feet [71]. It may lie plantar to the first metatarsal in 12% to 22% of feet [71]. Circulation to the second or third toes is supplied through the dorsalis pedis and first dorsal metatarsal arteries or through the communicating artery to the plantar metatarsal arteries and then to the plantar digital arteries [72].

Foot compartments are organized as follows: Medial compartment: Lies on the plantar surface of the hallux and contains the intrinsic muscles of the great toe and flexor digiti minimi [77]. Lateral compartment: Lies on the plantar surface of the fifth metatarsal and contains the abductor digiti minimi [77]. Central compartment: Lies on the plantar surface of the foot and contains the flexor digitorum brevis (superficial) and quadratus plantae (deep/calcaneal) [77]. Interosseous compartment: Lies dorsal to the other compartments between the metatarsals and contains the interosseous muscles and digital nerves [77].

The lumbrical muscles are located plantar to the transverse metatarsal ligament [78]. The interosseous tendons are located dorsal to the transverse metatarsal ligament [78].

Pathophysiology of Deformities

Lesser toe deformities result from an imbalance between the intrinsic and extrinsic musculotendinous units of the toes [53]. Hyperextension at the metatarsophalangeal (MTP) joint causes strong flexors to overpower the intrinsic extensors of the interphalangeal (IP) joints [53]. This muscle imbalance results in flexion deformities at the IP joints and extension deformities at the MTP joints [53]. Lesser MTP deformity starts with dysfunction of the plantar plate [53].

Specific deformity patterns are defined as: Mallet toe: A hyperflexion deformity at the distal interphalangeal (DIP) joint [53]. Hammer toe: A flexion deformity at the proximal interphalangeal (PIP) joint and an extension deformity at the MTP and DIP joints [53]. Claw toe: An extension deformity at the MTP joint combined with hyperflexion at the PIP and DIP joints [53].

In claw toe, flexor tendons pull the IP joints into flexion and the MTP joint into extension [53]. This mechanism depresses the metatarsal head and pulls the plantar fat pad distally, resulting in metatarsalgia, callus, or ulcer formation [53]. The primary deficiency at the MTP joint level in claw toe is dysfunction or tearing of the plantar plate [53].

Bunionette deformity is a forefoot protuberance laterally, dorsolaterally, or plantarlaterally along the fifth metatarsal head [38]. It is likely due to a multifactorial, anatomic interplay between fifth metatarsal bony morphology and forefoot soft-tissue imbalance [38]. Bunionette types are classified as: Type I: Distinguished by the presence of an enlarged fifth metatarsal head [51]. Type II: Demonstrates lateral bowing of the fifth metatarsal diaphysis [51]. Type III: Demonstrates an abnormally widened fourth–fifth metatarsal angle, with a normal angle being less than 8 degrees [51].

Hallux valgus is defined as lateral deviation of the great toe with medial deviation of the first metatarsal [69]. Its pathophysiology is likely multifactorial, involving intrinsic factors such as genetic predisposition, ligamentous laxity, and predisposing anatomy [69]. Extrinsic factors such as certain types of shoewear (narrow toe box, high heels) play a role in hallux valgus pathophysiology [69]. The pathoanatomy involves medial capsular attenuation [69]. In hallux valgus, the proximal phalanx drifts laterally, leading to plantar-lateral migration of the abductor hallucis [69]. The change in abductor hallucis position causes the proximal phalangeal unit to plantar flex and pronate the hallux [69]. The pronation of the hallux is amplified by the proximal phalangeal attachment of the adductor hallucis [69]. Lateral deviation of the extensor hallucis longus and flexor hallucis longus causes a muscular imbalance and deforming force for valgus progression and pronation of the great toe [69]. The first metatarsal head moves medially off the sesamoids, increasing the intermetatarsal angle [69]. Pronation of the first metatarsal leads to rounding of the lateral head, which should have a flat contour with no rotational deformity [69]. Secondary contracture occurs in the lateral capsule, adductor hallucis, and lateral metatarsal-sesamoid and intermetatarsal ligaments in hallux valgus [69].

Hallux valgus is a dynamic condition, and the deformity could be more correlated with motions during weightbearing than with plain static measurements [56]. Metatarsal pronation is associated with hallux valgus, with the underlying mechanism generally being cuneometatarsal instability [110]. Hallux valgus occurs almost exclusively in shoe-wearing societies [33]. Constricting footwear is implicated as a cause of hallux valgus [33]. The prevalence of hallux valgus was fifteen times higher in people who wore shoes than in those who did not in a study from China [33]. The prevalence of hallux valgus in women in Japan increased dramatically following the introduction of high-fashion footwear after World War II [33]. Pronation of the hindfoot has been suggested as a major cause of bunion formation [33]. Pes planus plays a minor role in bunion formation [33].

Hallux valgus deformity is defined as the lateral deviation of the proximal phalanx of the first metatarsophalangeal joint [90]. The etiology of hallux valgus is a combination of intrinsic factors such as genetic predisposition or a hypermobile first tarsometatarsal joint, and extrinsic factors predominantly related to high-heeled shoes with a narrow toe box [90]. Other predisposing factors for hallux valgus include rheumatoid or inflammatory arthritis, generalized ligamentous laxity, and dysmorphism of the first metatarsal [90]. The pathoanatomy of hallux valgus involves gradual failure of the medial supportive structures (medial collateral ligament and tibial sesamoid) resulting in a varus position of the first metatarsal [90]. Valgus deviation at the MTP joint of the proximal phalanx subsequently develops as hallux valgus progresses [90]. As hallux valgus progresses, the alignment of the flexor and extensor hallucis longus tendons shifts laterally relative to the MTP joint, further exacerbating the deformity [90]. Secondary pathology and deformity can develop in the lesser toes, such as hammertoes and claw toes, which may be symptomatic in patients with hallux valgus [90].

Adolescent bunion is frequently hereditary and usually seen in early adolescence [94]. Adolescent bunion is almost always found in conjunction with a wide forefoot caused by varus (medial deviation) of the first metatarsal shaft (metatarsus primus varus) [94]. The wide forefoot allows severe lateral deviation of the great toe (hallux valgus), causing the prominent base of the great toe to rub against the inside of the shoe and create a painful bunion [94]. Childhood hallux valgus is mainly due to distal M1 joint surface orientation abnormality, unlike in adults where increased M1M2 angle is the main deformity [114]. Subjects with concurrent neuropathy and claw toe deformity were associated with the smallest intrinsic foot muscle volumes and the thickest plantar aponeuroses [39]. Postoperative ischemia is a rare but immediate complication of lesser toe surgery, particularly in revision procedures and active smokers [9].

Classification

Typical Deformities: The standard classification of lesser toe deformities encompasses mallet toe, hammer toe, claw toe, curly toe, and crossover toe [13].

Associated Pathology: These deformities are frequently associated with abnormalities at the metatarsophalangeal (MTP) joints, specifically hallux valgus of the first MTP joint and instability of the lesser MTP joints, particularly the second toe [13]. Midfoot and hindfoot deformities may also coexist, including cavus foot, varus hindfoot, and valgus hindfoot with forefoot pronation [13].

Other Considerations: The pathology and management of these conditions involve describing normal anatomy and biomechanics, detailing the pathology of common adult deformities, and proposing management algorithms based on current literature [1]. Nonsurgical management focuses on relieving pressure and correcting deformity with various appliances [13]. Surgical management is reserved for patients who fail nonsurgical treatment [13]. Surgical options include soft-tissue correction (e.g., tendon transfer), bony procedures (e.g., joint resection, fusion, metatarsal shortening), or a combination of techniques [13].

Clinical Presentation

Patients presenting with lesser toe deformities may exhibit concurrent midfoot and hindfoot pathologies, including cavus foot, varus hindfoot, and valgus hindfoot with forefoot pronation [13]. The associated foot and ankle pain reduces mobility and negatively affects both physical and psychological quality of life [13].

In bunionette deformity, friction generated between the bony prominence, soft tissue, and associated constrictive footwear can result in keratosis, inflammation, pain, and ulceration [38].

Investigations

Plain radiography: Weight-bearing radiographs are strongly preferred for the initial imaging workup of foot and ankle pathology, with the exception of postoperative or traumatic situations that may warrant non-weight-bearing radiographs [87]. A standard series includes anteroposterior, lateral, and oblique views [87]. Dedicated radiographs of the toes and sesamoids may be indicated depending on the clinical context [87]. Stress radiographs are indicated when an unstable Lisfranc injury is suspected [87]. The hindfoot alignment view, also known as the Saltzman view, is commonly obtained to evaluate the axial alignment of the hindfoot in relation to the ankle for preoperative planning in corrective deformity surgery [87]. In the evaluation of metatarsalgia, radiographic assessment includes weight-bearing anteroposterior, lateral, and oblique views of the foot [92]. A skyline view of the metatarsal heads, obtained with the metatarsophalangeal joints in dorsiflexion, is helpful to evaluate overall alignment and demonstrate the height of the metatarsal heads, particularly in cases resulting from previous surgery [92]. Weight-bearing radiographs are useful for excluding a stress fracture of the metatarsal neck in the evaluation of interdigital neuroma [86]. In the evaluation of pes cavus, weight-bearing radiographs are required to assess deformity [99]. An increased Meary angle, where the long axis of the talus intersects the long axis of the first metatarsal dorsally on the lateral view, is a radiographic finding in pes cavus, with a normal value of 0° to 5° [99]. An increased calcaneal pitch, defined as the intersection of a line running along the undersurface of the calcaneus and the floor, indicates a calcaneocavus foot when greater than 30° [99].

In the evaluation of lesser toe deformities, abnormalities associated with the metatarsophalangeal joints include hallux valgus of the first MTP joint and instability of the lesser MTP joints, especially the second toe [13]. In the evaluation of hallux valgus, radiographic parameters include the hallux valgus angle, intermetatarsal angle, sesamoid bone position, and bone foot width [35]. The hallux valgus angle is defined as the angle between the long axis of the first metatarsal bone and that of the first proximal phalanx [35]. The intermetatarsal angle is defined as the angle between the long axis of the first and second metatarsal bones [35]. Bone foot width is measured as the distance between the most medial point of the first metatarsal head and the most lateral point of the fifth metatarsal head [35]. Hallux valgus angles based on margo medialis pedis measurements are slightly but statistically significantly smaller than metatarsophalangeal angles and should be considered conservative estimates [60]. Methods using the metatarsal shaft as a reference for measuring the metatarsophalangeal angle have poor measurement accuracy, especially postoperatively [65].

MRI: Magnetic resonance imaging can be useful in the diagnosis of metatarsalgia to distinguish among a neuroma, cyst, bursa, or synovitis [92]. MRI is a fundamental tool in the workup of a patient with a soft-tissue or bone tumor in the foot, allowing detection and definition of masses [96]. Focused MRI imaging of the metatarsophalangeal joints can detect sesamoid pathology and plantar plate injuries [96]. MRI is a valuable imaging modality for evaluating suspected bone or soft-tissue infection, as it can detect osteomyelitis early, well before radiographic abnormalities are visible [96]. In neuropathic patients, the specificity of MRI signal abnormalities for osteomyelitis is reduced, often necessitating a workup that includes scintigraphy, laboratory data, and physical examination [96]. Normal MRI marrow signal confidently excludes osteomyelitis in the evaluation of the diabetic foot [96]. For the evaluation of surrounding soft-tissue infection, MRI is the modality of choice, with contrast-enhanced sequences helpful in defining nonenhancing fluid collections or abscesses [96]. MRI may be useful for diagnosing interdigital neuroma, and the administration of contrast medium may increase its accuracy [86]. MRI of the spine is indicated in patients with unilateral pes cavus involvement [99].

Other Considerations: Ultrasonography has been reported to be 85% accurate in diagnosing interdigital neuroma [86]. Injection of the involved web space with local anesthetic that results in relief of neuritic symptoms is diagnostic of interdigital neuroma [86]. In the evaluation of cavus foot, a neurologic examination and family history are essential, with unilateral involvement suggesting a focal diagnosis such as spinal cord anomaly or nerve injury [99]. Bilateral involvement and a positive family history are common with Charcot-Marie-Tooth disease, although asymmetry may be seen [99]. Hindfoot flexibility in cavus foot is assessed by placing a 1-inch block under the lateral border of the foot, known as the Coleman block test [99].

Treatment

Non-Operative

Conservative management for lesser toe deformities focuses on symptom control rather than structural correction, as non-operative treatment cannot correct the deformity [34]. For mallet toe and hammer toe, patients are advised to wear shoes with high toe boxes and use foam or silicone gel toe sleeves [53]. Claw toe management similarly begins with shoe-wear modification, adequate plantar padding including metatarsal pad inserts, and a high-toe-box shoe, with crest pads also utilized for this deformity [53]. Symptomatic bunionettes are usually responsive to nonsurgical management, which includes shoewear modification, strategic padding, and shaving of the symptomatic callus [38, 51]. In bunionette deformity with plantar callus or associated pes planus, a metatarsal pad or custom orthotic device should be considered [51]. Steroid injections for claw toe have very limited indications and should be used judiciously, as they frequently result in weakening of the collateral ligaments and plantar plate, leading to progression and worsening of the deformity [53].

Operative

Indications: Surgical intervention is indicated when nonsurgical treatment fails for bunionette deformity [38]. For claw toe, surgery addresses MTP imbalance and associated components such as a long second metatarsal [53]. In cases of delayed diagnosis with subsequent arthritis, a first MTP fusion can restore stability and significantly improve function and should not be considered only for patients who are low demand [40].

Surgical Approach / Technique: Surgical correction of flexible mallet toe deformity is achieved with a percutaneous release of the FDL tendon at its insertion into the base of the distal phalanx [53]. Fixed mallet toe requires resection of the distal condyles of the middle phalanx and repair of the extensor tendon combined with temporary wire fixation [53]. In the absence of MTP pathology, hammer toe correction involves resection of the distal condyles of the proximal phalanx, which may be combined with an FDL tenotomy performed via a dorsal incision or through a plantar percutaneous release [53]. The toe is pinned with temporary wire fixation following hammer toe correction [53]. For claw toe, MTP imbalance is addressed with an extensor tendon Z-plasty lengthening and MTP capsular release, which may be combined with a distal oblique metatarsal shortening osteotomy when associated with a long second metatarsal [53]. An FDL-to-EDL (Girdlestone-Taylor) tendon transfer may be used to achieve balance of the affected MTP joint in claw toe deformity [53]. Newer procedures for claw toe include repairing the plantar plate at the proximal phalanx plantar insertion using a nonabsorbable suture passed through drill holes in the base of the proximal phalanx and tied dorsally with the toe positioned in slight plantar flexion [53]. When a crossover component is present, the damaged collateral ligament is repaired with nonabsorbable suture [53]. The hammer toe and mallet toe components of claw toe deformity are corrected via a proximal phalangeal distal condylar resection and FDL tenotomy, with a wire placed across the DIP, PIP, and MTP joints for temporary stabilization [53].

For bunionette deformity, surgical options depend on the underlying bony deformity. Lateral metatarsal head condylectomy is the treatment for type I bunionette [51]. Distal fifth metatarsal osteotomy (chevron) is the treatment for type II bunionette [51]. Oblique diaphyseal osteotomy is the treatment for type III bunionette [51]. Metatarsal head resection should be considered for salvage in bunionette deformity [51]. Proximal osteotomy should be avoided in bunionette deformity owing to the tenuous blood supply at the proximal metadiaphyseal junction of the fifth metatarsal [51]. Most type I and II bunionette deformities can be managed with the distal chevron osteotomy with minimal complications [17]. Type III bunionette deformities are effectively treated with diaphyseal osteotomy [17]. Percutaneous surgery for 5th ray deformity appears to be reproducible and effective in terms of subjective, clinical and radiological results [36].

In axial plane deformities, a shortening osteotomy of the metatarsal may be necessary to correct the deformity and instability of the metatarsophalangeal joint [101]. The Weil osteotomy is a preferred procedure for varus or valgus angulation of the toe not corrected with simple ligament balancing [101]. In the mildest cases of varus or valgus deformity, simple release of the contracted collateral ligament may be all that is necessary, with imbrication of the opposite side providing an additional measure of correction [101]. Satisfactory results have been reported with the use of the extensor digitorum brevis tendon rerouted underneath the transverse metatarsal ligament for varus deformity, provided a competent intermetatarsal ligament is present [101].

Implant Selection: Newer permanent implants are available to eliminate the need for K-wire fixation in hammer toe correction [53]. However, numerous studies have shown only minimal improvement in satisfaction without improvement in clinical outcomes, but at a significantly higher cost for the implants used in hammer toe correction [53].

Other Considerations: Persistent plantar plate dysfunction may result in recurrence of the deformity after claw toe surgery [53]. Recurrent MTP joint instability after surgical correction of mallet toe is usually a result of persistent plantar plate dysfunction [53]. The performance of associated tenotomies to incomplete phalanx osteotomies provides worse clinical outcomes, higher complication rates, and longer recovery time as compared to similar forefoot surgeries without tenotomies [29]. A shortening osteotomy of the metatarsal will prevent the use of the extensor digitorum brevis transfer [101].

Flexor digitorum brevis tendon transfer to the flexor digitorum longus tendon according to Valtin restored toe flexion in all patients with no recurrent claw toe deformity in posttraumatic flexible claw toe deformity due to extrinsic toe flexor shortening [7]. The percutaneous technique of PIP release, flexor digitorum brevis tenotomy, and proximal phalanx osteotomy provides effective realignment of PIP plantar flexion deformities of the second toe while preserving passive and active plantar flexion with good intermediate term results and a low rate of complications [2]. Arthroscopic-assisted correction of claw toe or overriding toe deformity via plantar plate tenodesis allows early toe mobilization and minimizes the risk of toe stiffness [4].

Surgical management of lesser toe deformities includes joint resection, fusion, metatarsal shortening, or a combination of techniques [13]. Joseph et al. reported a statistically significant reduction in pain, improvement in alignment, and full return to unrestricted weight-bearing activities in 31 patients with metatarsophalangeal joint fusions [101]. Complications of metatarsophalangeal joint fusions were relatively frequent: 13% with nonunions, 6% with implant breakage, and 3% with soft-tissue infection [101].

Metatarsosesamoid arthroscopy is effective for the management of intra-articular causes of plantar pain of the first metatarsophalangeal joint after surgical correction of hallux valgus deformity [24]. Arthroscopic correction of the hallux valgus deformity can achieve good clinical and radiologic results, provided that careful preoperative clinico–radiologic assessment is made to exclude patients contraindicated for the procedure [30]. The short-term results of the syndesmosis procedure for the treatment of hallux valgus are satisfactory, with good clinical and radiological results two years post-operatively [37]. Patients who underwent Scarf osteotomy had a gait pattern similar to that of their non-operated foot, whereas those who underwent arthrodesis of the first metatarsophalangeal joint did not totally recover the propulsive forces of the forefoot [58]. Although combined hemiepiphysiodesis does not create a large degree of correction as osteotomy, it did improve HV deformity with adequate growth remaining [43]. Minimally invasive surgery for juvenile hallux valgus allows another surgery to be done on minimally or undamaged tissues if needed later on [28]. Appropriate treatment for iatrogenic hallux varus requires careful clinical and radiological work-up to identify the causes, and each cause must then be corrected to achieve stable results over time [15]. The postoperative management must be meticulously carried out to ensure optimal alignment of the hallux [18].

Percutaneous distal metatarsal osteotomy is an effective and reliable method for correction of a mild-to-moderate hallux valgus deformity [6]. The minimally invasive distal linear osteotomy allows to achieve good clinical and radiographic outcomes comparable to those obtained with open surgical techniques in the management of mild to severe hallux valgus deformity, with decreased recovery and rehabilitation times [57]. Proximal first metatarsal osteotomy in combination with a lateral soft-tissue procedure is effective in correcting moderate to severe symptomatic hallux valgus deformity with metatarsus primus varus [5]. Proximal osteotomy is a good method for treating a severe hallux valgus deformity, with 86% of patients stating the operation was worthwhile after 8 years of follow-up [20]. The chevron osteotomy was found to be a reliable procedure for the correction of mild and moderate hallux valgus deformity, and outcome did not differ on the basis of age [27]. Better clinical and radiological outcomes can be achieved in patients with moderate to severe hallux valgus deformity operated by Lindgren–Turan distal metatarsal osteotomy when it combines with transosseous capsuloplasty [16]. The combination of modified scarf osteotomy for the great toe and modified metatarsal shortening offset osteotomy for the lesser toes is a novel surgical procedure for rheumatoid forefoot deformity that significantly improves clinical and radiological outcomes [11]. The combination of the modified Scarf osteotomy with medial capsular interposition and shortening metatarsal offset osteotomy was useful and safe in feet with noninflammatory arthritis [107]. During the first metatarsal osteotomy, a maximum of 6 mm shortening length is considered to be within the safe range [12]. Control of the crescentic osteotomy in the sagittal plane was unpredictable despite modification of the surgical technique, resulting in a 20% rate of persistent or new areas of increased pressure under the second metatarsal [47]. These results suggest that distal metatarsal osteotomy by minimal invasive surgery could be a safe and effective surgical procedure to be considered for metatarsalgias of the lesser rays [19]. Measurements of the Maestro criteria at the last followup showed a more balanced distribution in the Weil osteotomy group than in the DMMO group [32]. Recoil of the metatarsal heads between the pre-operative measurement and the last follow-up were identical and averaged 4 to 5 mm for each ray in DMMO patients [32]. This recoil was different between the rays in Weil osteotomy patients [32].

Male feet undergoing MITA present with worse baseline functional impairment but show greater early functional recovery, with clinical and radiographic outcomes comparable to those of female feet at 1 year [14]. Treatment options for foot deformities in Apert syndrome may include conservative means (i.e. insoles, orthopedic shoes) or surgery to improve biomechanics and normalize plantar pressures [26].

Complications

Surgical Technique: The performance of associated tenotomies to incomplete phalanx osteotomies provides higher complication rates compared to similar forefoot surgeries without tenotomies [29]. This combination also results in worse clinical outcomes [29] and longer recovery time [29] relative to procedures performed without tenotomies.

Radiological Degeneration: The radiological outcome of isolated Scarf osteotomies worsened with time [21]. Consequently, the classical Scarf osteotomy should not be recommended in patients with an increased lateral tilt of the metatarsal articular surface [21].

Other Considerations: Percutaneous correction of second toe proximal deformity is associated with a low rate of complications [2].

Recovery

Other Considerations: Percutaneous forefoot surgery offers theoretical advantages regarding lower morbidity and faster recovery [3]. Arthroscopic-assisted correction of claw toe or overriding toe deformity facilitates early toe mobilization and minimizes the risk of toe stiffness [4]. The performance of associated tenotomies to incomplete phalanx osteotomies results in a longer recovery time compared to similar forefoot surgeries without tenotomies [29]. Minimally invasive distal linear osteotomy allows for decreased recovery and rehabilitation times in the management of mild to severe hallux valgus deformity [57]. Male feet undergoing minimally invasive distal transverse metatarsal osteotomy (MITA) demonstrate greater early functional recovery compared to female feet [14].

Key Evidence

  • [L5] The paper describes the normal anatomy and biomechanics of the lesser toes, the pathology of commonly adult deformities, and discusses the rationale behind various treatment strategies, proposing management algorithms based on current literature. [1] (10.1302/2058-5241.1.160017)
  • [L4] The percutaneous technique provides effective realignment of PIP plantar flexion deformities of the second toe while preserving passive and active plantar flexion with good intermediate term results and a low rate of complications. [2] (10.1016/j.otsr.2015.06.009)
  • [L5] Percutaneous forefoot surgery provides treatment options for various forefoot disorders with theoretical advantages of lower morbidity and faster recovery, though it requires specific equipment and a lengthy learning curve. [3] (10.1016/j.otsr.2013.06.017)
  • [L4] The procedure allows early toe mobilization and minimizes the risk of toe stiffness. [4] (10.1007/s00402-006-0224-4)
  • [L4] Proximal first metatarsal osteotomy in combination with a lateral soft-tissue procedure is effective in correcting moderate to severe symptomatic hallux valgus deformity with metatarsus primus varus. [5] (10.1007/pl00013769)
  • [L2] The study shows that percutaneous distal metatarsal osteotomy is an effective and reliable method for correction of a mild-to-moderate hallux valgus deformity. [6] (10.1007/s00402-012-1585-5)
  • [Paper] The procedure restored toe flexion in all patients with no recurrent claw toe deformity. [7] (10.1016/j.otsr.2014.12.008)
  • [L4] The combination of modified scarf osteotomy for the great toe and modified metatarsal shortening offset osteotomy for the lesser toes is a novel surgical procedure for rheumatoid forefoot deformity that significantly improves clinical and radiological outcomes. [11] (10.3390/ijerph181910473)
  • [L5] During the first metatarsal osteotomy, a maximum of 6 mm shortening length is considered to be within the safe range. [12] (10.1186/s12891-019-2973-6)
  • [L5] [13] (10.5435/00124635-201108000-00006)
  • [L3] Male feet undergoing MITA present with worse baseline functional impairment but show greater early functional recovery, with clinical and radiographic outcomes comparable to those of female feet at 1 year. [14] (10.1186/s12891-026-10023-8)
  • [L5] Appropriate treatment for iatrogenic hallux varus requires careful clinical and radiological work-up to identify the causes, and each cause must then be corrected to achieve stable results over time. [15] (10.1016/j.otsr.2019.05.018)
  • [L3] Better clinical and radiological outcomes can be achieved in patients with moderate to severe hallux valgus deformity operated by Lindgren–Turan distal metatarsal osteotomy when it combines with transosseous capsuloplasty. [16] (10.1007/s00402-009-0986-6)
  • [L5] Most type I and II deformities can be managed with the distal chevron osteotomy with minimal complications, while type III deformities are effectively treated with diaphyseal osteotomy. [17] (10.5435/00124635-200705000-00008)
  • [L5] The postoperative management must be meticulously carried out to ensure optimal alignment of the hallux. [18] (10.5435/00124635-199501000-00005)
  • [L4] These results suggest that this could be a safe and effective surgical procedure to be considered for metatarsalgias of the lesser rays. [19] (10.1186/s13018-019-1159-0)
  • [L3] Proximal osteotomy is a good method for treating a severe hallux valgus deformity, with 86% of patients stating the operation was worthwhile after 8 years of follow-up. [20] (10.1007/bf00433994)
  • [L3] The radiological outcome of isolated Scarf osteotomies worsened with time, and the classical Scarf osteotomy should not be recommended in patients with an increased lateral tilt of the metatarsal articular surface; alternate osteotomies are thought to be superior in these cases. [21] (10.1007/s00264-010-0958-z)
  • [L5] Metatarsosesamoid arthroscopy is effective for the management of intra-articular causes of plantar pain of the first metatarsophalangeal joint after surgical correction of hallux valgus deformity. [24] (10.1016/j.eats.2024.102990)
  • [L5] Treatment options may include conservative means (i.e. insoles, orthopedic shoes) or surgery to improve biomechanics and normalize plantar pressures. [26] (10.1186/s12891-020-03812-2)
  • [L3] At these two follow-up periods, the chevron osteotomy was found to be a reliable procedure for the correction of mild and moderate hallux valgus deformity, and outcome did not differ on the basis of age. [27] (10.2106/00004623-200010000-00002)
  • [L5] Minimally invasive surgery for juvenile hallux valgus allows another surgery to be done on minimally or undamaged tissues if needed later on. [28] (10.1016/j.otsr.2021.103168)
  • [L3] The performance of associated tenotomies to incomplete phalanx osteotomies provides worse clinical outcomes, higher complication rates, and longer recovery time as compared to similar forefoot surgeries without tenotomies. [29] (10.1186/s13018-019-1353-0)
  • [L4] Arthroscopic correction of the hallux valgus deformity can achieve good clinical and radiologic results, provided that careful preoperative clinico–radiologic assessment is made to exclude patients contraindicated for the procedure. [30] (10.1016/j.arthro.2008.03.001)
  • [L3] [32] (10.1016/j.otsr.2011.07.003)
  • [L5] [33] (10.2106/00004623-199606000-00018)
  • [L5] Non-operative treatment cannot correct the deformity but can help control symptoms. [34] (10.1302/2058-5241.1.000005)
  • [L4] [35] (10.1186/s13018-025-06361-3)
  • [L4] Percutaneous surgery for 5th ray deformity appears to be reproducible and effective in terms of subjective, clinical and radiological results. [36] (10.1016/j.otsr.2014.11.017)
  • [L4] The short-term results of this surgical procedure for the treatment of hallux valgus are satisfactory, with good clinical and radiological results two years post-operatively. [37] (10.1302/0301-620x.96b4.32193)
  • [L5] [38] (10.5435/jaaos-d-17-00345)
  • [L4] Subjects with concurrent neuropathy and claw toe deformity were associated with the smallest intrinsic foot muscle volumes and the thickest plantar aponeuroses. [39] (10.1186/s12891-020-03503-y)
  • [Paper] In cases of delayed diagnosis with subsequent arthritis, a first MTP fusion can restore stability and significantly improve function and should not be considered only for patients who are low demand. [40] (10.1016/j.csm.2020.07.007)
  • [L4] Although combined hemiepiphysiodesis does not create a large degree of correction as osteotomy, it did improve HV deformity with adequate growth remaining. [43] (10.1186/s12891-019-2867-7)
  • [L3] Control of the crescentic osteotomy in the sagittal plane was unpredictable despite modification of the surgical technique, resulting in a 20% rate of persistent or new areas of increased pressure under the second metatarsal. [47] (10.1097/01.blo.0000191269.50033.ec)
  • [L5] Hallux valgus is a dynamic condition, and the deformity could be more correlated with motions during weightbearing than with plain static measurements. [56] (10.1097/corr.0000000000002265)
  • [L5] The minimally invasive distal linear osteotomy allows to achieve good clinical and radiographic outcomes comparable to those obtained with open surgical techniques in the management of mild to severe hallux valgus deformity, with decreased recovery and rehabilitation times. [57] (10.1007/s00402-013-1778-6)
  • [L3] Patients who underwent Scarf osteotomy had a gait pattern similar to that of their non-operated foot, whereas those who underwent arthrodesis of the first metatarsophalangeal joint did not totally recover the propulsive forces of the forefoot. [58] (10.1302/0301-620x.98b5.36406)
  • [L4] Because the hallux valgus angles based on margo medialis pedis measurements were slightly but statistically significantly smaller, these measurements should be considered conservative estimates of the metatarsophalangeal angle. [60] (10.1186/1471-2474-15-133)
  • [L4] The reduction of the PIP joint using an intramedullary nitinol implant is a good option in lesser toe deformities, with few complications and a high rate of arthrodesis. [62] (10.1007/s00402-019-03203-w)
  • [L4] Methods using the metatarsal shaft as a reference have poor measurement accuracy, especially postoperatively. [65] (10.2106/00004623-200303000-00015)
  • [L4] The combination of the modified Scarf osteotomy with medial capsular interposition and shortening metatarsal offset osteotomy was useful and safe in feet with noninflammatory arthritis. [107] (10.2106/jbjs.21.01486)
  • [L4] The study found metatarsal pronation to be associated with hallux valgus, with the underlying mechanism generally being cuneometatarsal instability. [110] (10.1016/j.otsr.2012.05.005)
  • [L3] Childhood hallux valgus is mainly due to distal M1 joint surface orientation abnormality, unlike in adults where increased M1M2 angle is the main deformity. [114] (10.1016/j.otsr.2021.102938)

See Also

References

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[2] Percutaneous correction of second toe proximal deformity: Proximal interphalangeal release, flexor digitorum brevis tenotomy and proximal phalanx osteotomy. Orthopaedics & Traumatology: Surgery & Research. 2015. DOI: 10.1016/j.otsr.2015.06.009

[3] Percutaneous forefoot surgery. Orthopaedics & Traumatology: Surgery & Research. 2014. DOI: 10.1016/j.otsr.2013.06.017

[4] Arthroscopic-assisted correction of claw toe or overriding toe deformity: plantar plate tenodesis. Archives of Orthopaedic and Trauma Surgery. 2006. DOI: 10.1007/s00402-006-0224-4

[5] Moderate to severe hallux valgus deformity: correction with proximal crescentic osteotomy and distal soft-tissue release. Archives of Orthopaedic and Trauma Surgery. 2000. DOI: 10.1007/pl00013769

[6] Percutaneous distal metatarsal osteotomy versus distal chevron osteotomy for correction of mild-to-moderate hallux valgus deformity. Archives of Orthopaedic and Trauma Surgery. 2012. DOI: 10.1007/s00402-012-1585-5

[7] Flexor digitorum brevis tendon transfer to the flexor digitorum longus tendon according to Valtin in posttraumatic flexible claw toe deformity due to extrinsic toe flexor shortening. Orthopaedics & Traumatology: Surgery & Research. 2015. DOI: 10.1016/j.otsr.2014.12.008

[9] Combined Hammer Toe and Mallet Toe Deformity with Associated Double Corns. 2020.

[11] Combination of Modified Scarf Osteotomy and Metatarsal Shortening Offset Osteotomy for Rheumatoid Forefoot Deformity. International Journal of Environmental Research and Public Health. 2021. DOI: 10.3390/ijerph181910473

[12] Impact of first metatarsal shortening on forefoot loading pattern: a finite element model study. BMC Musculoskeletal Disorders. 2019. DOI: 10.1186/s12891-019-2973-6

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[14] Gender differences in early functional recovery after minimally invasive distal transverse metatarsal osteotomy - Akin Osteotomy (MITA) for hallux valgus: a propensity-matched study of 300 cases. BMC Musculoskeletal Disorders. 2026. DOI: 10.1186/s12891-026-10023-8

[15] Surgical treatment of iatrogenic hallux varus. Orthopaedics & Traumatology: Surgery & Research. 2020. DOI: 10.1016/j.otsr.2019.05.018

[16] Transosseous capsuloplasty improves the outcomes of Lindgren–Turan distal metatarsal osteotomy in moderate to severe hallux valgus deformity. Archives of Orthopaedic and Trauma Surgery. 2009. DOI: 10.1007/s00402-009-0986-6

[17] Bunionette Deformity. Journal of the American Academy of Orthopaedic Surgeons. 2007. DOI: 10.5435/00124635-200705000-00008

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[19] Evaluation of results after distal metatarsal osteotomy by minimal invasive surgery for the treatment of metatarsalgia: patient and anatomical pieces study. Journal of Orthopaedic Surgery and Research. 2019. DOI: 10.1186/s13018-019-1159-0

[20] Proximal osteotomy in hallux valgus, long-term results of 167 operated feet. Archives of Orthopaedic and Trauma Surgery. 1997. DOI: 10.1007/bf00433994

[21] Mid-term results of Scarf osteotomy in hallux valgus. International Orthopaedics. 2010. DOI: 10.1007/s00264-010-0958-z

[24] Metatarsosesamoid Arthroscopy for Management of Plantar Pain of the First Metatarsophalangeal Joint After Surgical Correction of Hallux Valgus Deformity. Arthroscopy Techniques. 2024. DOI: 10.1016/j.eats.2024.102990

[26] Is the Apert foot an overlooked aspect of this rare genetic disease? Clinical findings and treatment options for foot deformities in Apert syndrome. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03812-2

[27] The Chevron Osteotomy for Correction of Hallux Valgus. The Journal of Bone and Joint Surgery-American Volume. 2000. DOI: 10.2106/00004623-200010000-00002

[28] Treatment of hallux valgus in children and adolescents. Orthopaedics & Traumatology: Surgery & Research. 2022. DOI: 10.1016/j.otsr.2021.103168

[29] The impact of associated tenotomies on the outcome of incomplete phalangeal osteotomies for lesser toe deformities. Journal of Orthopaedic Surgery and Research. 2019. DOI: 10.1186/s13018-019-1353-0

[30] Arthroscopy‐Assisted Correction of Hallux Valgus Deformity. Arthroscopy. 2008. DOI: 10.1016/j.arthro.2008.03.001

[32] Distal osteotomy of the lateral metatarsals: A series of 72 cases comparing the Weil osteotomy and the DMMO percutaneous osteotomy. Orthopaedics & Traumatology: Surgery & Research. 2011. DOI: 10.1016/j.otsr.2011.07.003

[33] Instructional Course Lectures, The American Academy of Orthopaedic Surgeons - Hallux Valgus†. The Journal of Bone & Joint Surgery*. 1996. DOI: 10.2106/00004623-199606000-00018

[34] Treatment of hallux valgus deformity. EFORT Open Reviews. 2016. DOI: 10.1302/2058-5241.1.000005

[35] Outcomes and Complications for Minimally Invasive Distal Transverse Metatarsal Osteotomy–Akin Osteotomy (MITA) for Hallux Valgus: 493 Cases. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-025-06361-3

[36] Percutaneous bunionette correction: Results of a 49-case retrospective study at a mean 34 months’ follow-up. Orthopaedics & Traumatology: Surgery & Research. 2015. DOI: 10.1016/j.otsr.2014.11.017

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[38] Management of Bunionette Deformity. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-17-00345

[39] Neuropathy, claw toes, intrinsic muscle volume, and plantar aponeurosis thickness in diabetic feet. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03503-y

[40] Turf Toe, Traumatic Hallux Valgus, and Hallux Rigidus -What Can I Do After an Metatarsophalangeal Fusion?. Clinics in Sports Medicine. 2020. DOI: 10.1016/j.csm.2020.07.007

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[47] Surgery for Hallux Valgus with Proximal Crescentic Osteotomy Causes Variable Postoperative Pressure Patterns. Clinical Orthopaedics & Related Research. 2006. DOI: 10.1097/01.blo.0000191269.50033.ec

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[62] The efficacy of an intramedullary nitinol implant in the correction of claw toe or hammertoe deformities. Archives of Orthopaedic and Trauma Surgery. 2019. DOI: 10.1007/s00402-019-03203-w

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[114] Abnormalities in distal first metatarsal joint surface orientation: Distal Metatarsal Articular Angle and Distal Metatarsal-2 Articular Angle. Orthopaedics & Traumatology: Surgery & Research. 2021. DOI: 10.1016/j.otsr.2021.102938

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