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Subtalar fusion

72 citationsUpdated Sep 2026

Overview

Subtalar arthrodesis serves as a definitive salvage procedure for combined end-stage ankle and subtalar arthrosis, severe planar deformities, and posttraumatic arthritis, providing a stable and painless foot for ambulation [3]. While tibiotalocalcaneal arthrodesis is primarily a salvage intervention, most patients derive significant benefit from the procedure [18]. The technique is also indicated for markedly comminuted Sanders type IV calcaneal fractures, particularly when surgical treatment is delayed, and for calcaneal malunion, where it yields high rates of successful arthrodesis and patient satisfaction [15, 10]. Triple arthrodesis remains a technically demanding option with prolonged recovery times and is rarely appropriate outside of specific indications [24, 11].

Operative management offers multiple effective approaches, including open, arthroscopic, and medial techniques. Arthroscopic subtalar arthrodesis provides consistent improvement in posttraumatic arthritis with union rates comparable to open methods [19, 20]. A systematic review confirms high union rates for both open and arthroscopic techniques [8]. Medial approach arthrodesis is a safe alternative that guarantees long-term fusion, prevents non-unions, and significantly reduces wound complications while correcting fixed deformities [4]. For surgeons experienced in posterior arthroscopy, posterior arthroscopic tibiotalocalcaneal arthrodesis offers superior exposure, high patient satisfaction, and lower postoperative morbidity than traditional methods [22].

Outcomes are influenced by specific technical factors rather than the choice of approach alone. All three operative approaches do not influence the fusion rate or time to fusion [5]. Successful bone union within six postoperative months is associated with the use of fully threaded screws, autograft, and two screws compared to a single screw [21]. However, no statistically significant differences in union rates, time to union, or postoperative AOFAS scores were found between autografts, allografts, synthetic grafts, and no grafts [25]. Initial operative treatment for displaced intra-articular calcaneal fractures prior to subtalar arthrodesis results in significantly higher Maryland Foot Scores and fewer wound complications compared to initial nonoperative treatment [2]. In cases where soft tissue conditions limit safe access, satisfactory functional outcomes and pain relief can be achieved through tibiotalar fusion and subtalar joint immobilization, even without complete fusion [6].

Anatomy & Pathophysiology

Bony Anatomy and Ligaments

The ankle joint comprises the tibia, talus, and fibula, functioning as a ginglymus (hinge) joint [75]. The talar dome is biconcave with a central talar sulcus, and its radius of curvature is greater laterally [75]. The deltoid ligament consists of two distinct layers [75]. The superficial layer includes the tibionavicular and tibiocalcaneal ligaments, which cross both the ankle and subtalar joints [75]. The deep layer contains the anterior and posterior tibiotalar ligaments, which cross only the ankle joint [75]. The calcaneofibular ligament crosses both the ankle and the subtalar joint [75]. Additionally, the interosseous talocalcaneal ligament is also known as the cervical ligament [78], and the plantar calcaneonavicular ligament is also known as the spring ligament [78].

Muscles and Tendons

The gastrocnemius, soleus, and plantaris muscles insert on the calcaneus through the Achilles tendon [56]. The posterior tibialis muscle inserts on the navicular, plantar surface of the second, third, and fourth metatarsals, cuboid, and sustentaculum talus [56]. The peroneus longus muscle inserts on the medial cuneiform and base of the first metatarsal [56], while the peroneus brevis muscle inserts on the base of the fifth metatarsal [56].

Vascular and Neural Anatomy

The tibial nerve divides into three terminal branches before reaching the foot: the medial calcaneal nerve, lateral plantar nerve, and medial plantar nerve [70]. 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 [70]. The flexor retinaculum acts as the roof of the tarsal tunnel and extends from the medial malleolus to the medial side of the calcaneal tuberosity [70].

Biomechanics and Contact Characteristics

Subtalar joint contact area ratios and high-pressure zones increase with load [62]. Inversion of the subtalar joint reduces contact area while maintaining high pressures [62]. Increasing fibular load broadens the posterior facet contact area of the subtalar joint [62]. Talar neck misalignment significantly unloads the combined anterior/middle facet of the subtalar joint, except for medial displacement [68]. This misalignment may create an extraarticular load path or increase loading directly on the talonavicular joint [68]. A significant increase in subtalar joint plantar flexion is a primary compensation during overground walking and double heel-rise activity following tibiotalar arthrodesis [45].

Pathophysiology of Deformity and Arthritis

Persistent disabling pain after a calcaneal fracture results from joint incongruity leading to subtalar arthritis and deformation of the overall morphology of the calcaneus [12]. Anterior ankle pain after calcaneal fracture can result from abutment between the neck of the talus and anterior lip of the tibia due to horizontal positioning of the talus [12]. Lateral hindfoot pain after calcaneal fracture commonly results from peroneal tendinitis, calcaneofibular impingement, or sural neuritis [12]. Weakening of the gastrocnemius-soleus complex–soleus mechanism may result from elevation of the insertion of the Achilles tendon or shortening of the calcaneal lever arm [12].

Total dislocation of the talus results from excessive supination or excessive pronation, with supination being the more frequent mechanism [27]. Substantial ankle malalignment, mostly varus deformity, is common in ankles with end-stage osteoarthritis [30]. Joint facet area and fusion of the subtalar articular surface are closely related to the severity of flat foot deformity [26]. Type I and Type IV subtalar articular surface types are more likely to develop severe flat foot deformity [26]. The morphology of the subtalar joint is important in determining underlying foot posture in vivo [57].

Cavus foot is frequently accompanied by hindfoot varus deformity [54]. In cavus foot, the forefoot is severely plantar flexed on the hindfoot, requiring marked ankle dorsiflexion to compensate [54]. Severe cavus deformity can block ankle dorsiflexion, leading to anterior ankle impingement and pain [54]. The cause of cavus foot is usually muscle imbalance in a growing foot [54]. Cavus foot is rarely found in the absence of an underlying neuromuscular condition [54]. Rigid flatfoot deformities in adolescents have a less predictable clinical course and are associated with various underlying causes [13].

Posttraumatic arthritis of the tibial plafond occurs at an approximately 39% rate after fractures [40]. Radiographic appearance of subtalar arthritis after intra-articular calcaneal fractures has been noted in >21% of patients at 17 months [40]. Initial cartilage damage in pilon fractures is associated with early to mid-term osteoarthritis development and worse functional outcomes [40]. Tarsal coalition is a source of constriction beneath and adjacent to the tarsal tunnel [70]. A fixed valgus hindfoot can predispose to chronic traction neuropathy of the posterior tibial nerve or one of its branches [70].

Classification

Talo-calcaneal Coalition: A new classification system was developed specifically to facilitate operative planning for talocalcaneal coalition [96].

Peri-implant Fractures: Given the lack of consensus on treatment, a classification system may be helpful to guide clinical practice for peri-implant fractures around hindfoot fusion nails [52].

Clinical Presentation

Posttraumatic Arthritis and Deformity

Persistent disabling pain following calcaneal fracture stems from joint incongruity that leads to subtalar arthritis and from the deformation of the overall calcaneal morphology [12]. Anterior ankle pain may arise from abutment between the talar neck and the anterior tibial lip, a consequence of the talus assuming a horizontal position due to impaction into the calcaneus [12]. Patients often report difficulty wearing shoes because the widened calcaneus and malleoli rub against the heel counter [12]. Lateral hindfoot pain commonly results from peroneal tendinitis, calcaneofibular impingement, or sural neuritis [12]. Initial cartilage damage is associated with early to mid-term osteoarthritis development and worse functional outcomes [40]. Poor results characterized by pain and limited subtalar motion are produced by associated fractures involving the subtalar or talonavicular joints, open dislocations, and associated injuries requiring immobilization for more than three weeks [42].

Tarsal Coalition

Patients with tarsal coalitions often present with a symptomatic flatfoot [92]. Pain is typically localized to the sinus tarsi or along the medial longitudinal arch [92]. Limited subtalar motion may manifest as difficulty moving on uneven ground and/or frequent ankle sprains [92]. Talocalcaneal coalitions occur in children between 12 and 15 years of age and can involve any of the three subtalar joint facets, with the middle facet being most common [92]. The joint facet area and fusion of the subtalar articular surface are closely related to the severity of flatfoot deformity, with Type I and IV coalitions being more likely to develop severer flatfoot deformity [26].

Radiographic Findings: Lateral radiographs may demonstrate dorsal talar beaking, a nonspecific finding associated with many coalitions that is not a sign of degenerative arthrosis [92]. Harris axial radiographs have a high false-positive rate for tarsal coalition if the view is slightly oblique to the posterior or middle facet [92].

Other Etiologies

Rigid flatfoot deformities in adolescents have a less predictable clinical course and are associated with various underlying causes, making it critical to investigate the etiology to recommend proper management [13]. Standard radiographs may fail to detect occult talar neck fractures associated with subtalar dislocation, making fluoroscopy and CT mandatory for evaluation [64].

Investigations

Plain radiography: Weight-bearing radiographs are strongly preferred for the initial imaging workup of foot and ankle pathology, with exceptions for postoperative or traumatic situations that may warrant non-weight-bearing radiographs [82]. A standard series includes AP, lateral, and mortise views [82]. In the adult, the standard ankle views are AP, mortise (an AP view with the ankle internally rotated 15–20 degrees), and lateral [85]. The calcaneum is usually X-rayed in axial and lateral views [85]. Weight-bearing X-rays help show the coronal relationship of heel to tibia in stance [85]. Stress X-rays complement clinical tests for ankle stability [85]; if stress manoeuvres are painful, they can be carried out under general anaesthesia [85]. Medial and lateral oblique projections allow better assessment of the subtalar joint [85]. The Broden view is a special hindfoot view used to assess the posterior facet of the subtalar joint, particularly when evaluating intra-articular calcaneal fractures or subtalar coalition [82]. The hindfoot alignment view, or Saltzman view, is commonly obtained to evaluate axial hindfoot alignment in relation to the ankle and is particularly important for preoperative planning in corrective hindfoot deformity surgery [82]. For cavus foot evaluation, weight-bearing radiographs are required [90]. 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 cavus foot; the normal value is 0° to 5° [90]. 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° [90].

CT: Computed tomography scans are important in assessing fractures and for congenital bony coalitions [85].

MRI: Magnetic resonance imaging and ultrasound are used to demonstrate soft-tissue problems, such as tendon and ligament injuries [85]. MRI can also be used to diagnose joint effusions and bone infections [85]. MRI of the spine is indicated with unilateral involvement in patients with cavus foot [90].

Bone scan: Radio-isotope scanning is excellent for localizing areas of abnormal blood flow or bone remodelling activity, signs that suggest the presence of covert infection [85].

Other Considerations: Hindfoot flexibility is assessed by placing a 1-inch block under the lateral border of the foot (Coleman block test) [90]. A neurologic examination and a family history are essential for the evaluation of cavus foot [90]. Unilateral involvement in cavus foot suggests a focal diagnosis, such as spinal cord anomaly or nerve injury [90]. Bilateral involvement and a positive family history are common with Charcot-Marie-Tooth disease [90]. Rigid flatfoot deformities in adolescents are associated with various underlying causes, making it critical to investigate the etiology to recommend proper management [13]. Joint facet area and fusion of the subtalar articular surface were closely related to the severity of flat foot deformity [26]. Type I and IV subtalar articular surface types were more likely to develop severer flat foot deformity [26]. The anatomy of the subtalar joint presents significant individual variations in the Chinese population, with nearly two thirds of individuals having partly or completely fused anterior and middle facets [44].

Treatment

Non-Operative

The provided evidence does not detail specific conservative management protocols such as weight loss, physical therapy, NSAIDs, or injections. Surgical intervention is discussed primarily in the context of post-traumatic pathology, malunion, or failed joint preservation.

Operative

Indications: Surgical reconstruction for post-traumatic foot and ankle issues most often requires subtalar arthrodesis in conjunction with other procedures designed to address the morphology of the calcaneus [12]. Primary subtalar arthrodesis is especially indicated for markedly comminuted Sanders type IV calcaneal fractures when surgical treatment is delayed [15]. Triple arthrodesis should be performed only according to specific indications and is rarely appropriate [11]. It serves as a salvage operation for a painful, unstable foot or a foot with a fixed, disabling deformity [67]. In the presence of a well-preserved subtalar joint with a lateral wall bulge causing peroneal tendinitis or calcaneal fibular impingement, a good result can be achieved solely with lateral wall decompression [12]. However, four of seven patients who underwent lateral wall exostectomy alone had a poor result with persistent pain, emphasizing the need for proper patient selection [12].

Surgical Approach / Technique: Surgical treatment for calcaneal malunion, including ostectomy, subtalar arthrodesis, or corrective osteotomy, has a high rate of successful arthrodesis and patient satisfaction [10]. The modified Blair arthrodesis provides a normal-appearing foot, produces no shortening, and allows motion to remain at the talonavicular and anterior subtalar joints [34]. Arthrodesis in patients with arthrosis and talar osteonecrosis may be successfully accomplished with use of bone graft spanning the affected joints and rigid fixation [39]. A posterior approach can provide an alternative for a fresh soft tissue plane for hindfoot arthrodesis in high-risk patients with compromised soft tissues [29]. Triple arthrodesis in older patients relieves or lessens pain; however, because of its technical difficulty and the relatively high rate of postoperative complications, it should be used only as a salvage operation for a painful, unstable foot or a foot that has a fixed, disabling deformity [67].

Arthroscopic Techniques: The LEAP subtalar arthrodesis technique is an efficient way to correct the hindfoot deformity and achieve sound arthrodesis of the subtalar joint [41]. The 2-portal lateral approach to arthroscopic subtalar arthrodesis is reproducible and safe with regard to the surrounding nerves [58]. Management of arthroscopic tibiotalar and subtalar joint arthrodesis may be on a day-surgery basis, and indications are the same as for open arthrodesis provided deformity can be reduced [51]. With two simple modifications, the indication for arthroscopic posterior subtalar arthrodesis could be extended to primary arthrodesis of Sanders type IV fractures of the calcaneus [99].

Tibiotalocalcaneal (TTC) Fusion: Tibiotalocalcaneal arthrodesis with a specifically designed retrograde intramedullary nail without formal débridement of the subtalar joint and a choice between open or percutaneous débridement of the ankle is a reliable method to achieve fusion [31]. All patients treated with tibiotalocalcaneal arthrodesis using a hindfoot intramedullary nail had fusion at followup radiograms and were able to walk full weight bearing without pain [50].

Outcomes and Complications: Primary subtalar arthrodesis for markedly comminuted Sanders type IV calcaneal fractures yields good mid-term results [15]. Both arthroscopic subtalar arthrodesis (ASTA) and open subtalar arthrodesis (ISTA) techniques are effective procedures for subtalar arthrodesis [93]. Calcaneal nonunion is rare but may be more common after conservative treatment; smoking may play a role in its pathophysiology [102]. This unique staged procedure for complete talar extrusion resulted in fair outcomes in terms of AOFAS ankle-hindfoot score and allowed the patient to continue with activities of daily living without complications of infection or collapse requiring additional unplanned procedures [9]. The relief of pain and the restoration of function achieved through effective correction of the severe pes planovalgus deformity account for the satisfactory outcomes [37]. Survival of the talar body prosthesis can provide satisfactory ankle and foot function for ten to thirty-six years, although early prosthesis failure may occur [36]. For patients with pain at the site of a failed ankle arthrodesis, conversion to total ankle arthroplasty with the use of a three-component ankle implant is a viable treatment option that provides reliable intermediate-term results [17].

Complications

Wound and Soft Tissue Complications: Postoperative wound complications are significantly reduced when subtalar and talonavicular arthrodesis is performed via a medial approach [4]. In patients with displaced intra-articular calcaneal fractures, initial operative treatment results in fewer postoperative wound complications compared with initial nonoperative treatment prior to subtalar arthrodesis [2]. For high-risk patients with compromised soft tissues, a posterior approach provides an alternative by creating a fresh soft tissue plane for hindfoot arthrodesis [29]. Arthroscopic tibiotalocalcaneal arthrodesis is associated with lower postoperative morbidity than traditional methods [22], and while nonunion rates are similar between arthroscopic and open combined ankle and subtalar fusion, wound complication rates are lower in the arthroscopic group [112].

Nonunion and Aseptic Necrosis: Successful bone union within six postoperative months after subtalar arthrodesis for posttraumatic arthritis is associated with the use of fully threaded screws, autograft, and two screws compared to a single screw [21]. Arthroscopic subtalar arthrodesis offers a union rate similar to published series of open arthrodesis for posttraumatic arthritis following calcaneal fractures [19]. The Hoke triple arthrodesis has an overall aseptic necrosis rate of 6.5%, which has been eliminated by modifying the technique to preserve the artery to the tarsal canal [114]. Tibiotalocalcaneal arthrodesis with headless compression screws is associated with a high fusion rate and low incidence of complications [14]. In a series of twenty-one patients undergoing tibiotalocalcaneal arthrodesis, satisfactory results were obtained in approximately 75 per cent, with osseous union radiographically evident in all but three patients [66]. A study of tibiotalar arthrodesis associated with fibular shortening osteotomy demonstrated a 97.6% fusion rate and a nonunion rate much lower than reported elsewhere [63]. Primary fusion was obtained in sixteen of eighteen patients undergoing arthrodesis of the ankle [28]. Clinical outcomes and the proportion achieving union were significantly better in the vascularised group compared with the conventional arthrodesis group for ankle arthrodesis using an anterior sliding tibial graft [116].

Infection and Salvage Procedures: Infection risks and heterogeneity across studies highlight the need for standardized protocols and larger controlled trials to optimize patient selection and postoperative management in tibiotalocalcaneal arthrodesis for Charcot neuroarthropathy [115]. An aggressive operative approach is recommended for local complications, and early amputation may improve function and reduce burden in follow-up evaluation of open intra-articular fractures of the calcaneus [69]. Triple arthrodesis should be used only as a salvage operation for a painful, unstable foot or a foot that has a fixed, disabling deformity due to its technical difficulty and relatively high rate of postoperative complications [67].

Implant-Related Complications: Peri-implant fractures around hindfoot fusion nails lack consensus on treatment, and a classification system may be helpful to guide clinical practice [52]. Retrograde intramedullary nailing provides a load-sharing fixation device with superior biomechanical properties and is an excellent choice for use in tibiotalocalcaneal arthrodesis [35]. Low complication rates contribute to making tibiotalocalcaneal arthrodesis using an intramedullary nail a safe procedure [113].

Functional and Deformity Outcomes: A significant increase in subtalar joint plantar flexion is a primary compensation during overground walking and a double heel-rise activity following tibiotalar arthrodesis [45]. The relief of pain and the restoration of function achieved through effective correction of the severe pes planovalgus deformity account for the satisfactory outcomes in complex reconstruction [37].

Recovery

Light activity (weeks): The provided evidence does not specify a typical week range for light activities such as desk work, driving, or light ADLs.

Full activity (months): The provided evidence does not specify a month range for the return to manual work, sport, or full range of motion and strength.

Complete recovery / outcome plateau (months): The provided evidence does not specify a month range for the stabilization of pain, strength, and final functional outcomes.

Rehabilitation protocol: The evidence does not detail specific physiotherapy phasing, immobilisation duration, or weight-bearing progression protocols. However, tibiocalcaneal arthrodesis allows patients to return to mobility with good to excellent patient satisfaction [111]. In cases where soft tissue conditions limit safe access to the subtalar joint, satisfactory functional outcomes and pain relief can be achieved through tibiotalar fusion and subtalar joint immobilization, even without complete fusion [6].

Functional milestones: Patients who underwent initial operative treatment before subtalar arthrodesis had significantly higher Maryland Foot Scores compared with those who underwent initial nonoperative treatment [2]. Primary subtalar arthrodesis for markedly comminuted Sanders type IV calcaneal fractures yields good results even 5 years post-operation [65]. All patients undergoing tibiotalocalcaneal arthrodesis using a hindfoot intramedullary nail were able to walk full weight bearing without pain [50]. A significant increase in subtalar joint plantar flexion is a primary compensation during overground walking following tibiotalar arthrodesis [45]. A significant increase in subtalar joint plantar flexion is a primary compensation during a double heel-rise activity following tibiotalar arthrodesis [45].

Other Considerations: A systematic review found a high rate of union among patients who underwent open subtalar arthrodesis [8]. A systematic review found a high rate of union among patients who underwent arthroscopic subtalar arthrodesis [8]. All three operative approaches do not influence the fusion rate of the subtalar joint [5]. All three operative approaches do not influence the fusion time of the subtalar joint [5]. Subtalar and talonavicular arthrodesis through a medial approach guarantees long-term fusion [4]. Subtalar and talonavicular arthrodesis through a medial approach prevents non-unions [4]. Subtalar and talonavicular arthrodesis through a medial approach provides significant correction of fixed deformities [4]. Tibiotalocalcaneal fusion provides a stable and painless foot for ambulation [3]. Tibiotalocalcaneal arthrodesis with headless compression screws is associated with a short operation time [14]. Tibiotalocalcaneal arthrodesis with headless compression screws is associated with a high fusion rate [14]. Tibiotalocalcaneal arthrodesis with headless compression screws is associated with a low incidence of complications [14]. Tibiotalocalcaneal arthrodesis with headless compression screws is associated with good postoperative recovery [14]. All patients undergoing tibiotalocalcaneal arthrodesis using a hindfoot intramedullary nail had fusion at followup radiograms [50]. Patients who underwent initial operative treatment before subtalar arthrodesis had fewer postoperative wound complications compared with those who underwent initial nonoperative treatment [2]. Triple arthrodesis generally involves a prolonged recovery time [24].

Key Evidence

  • [L5] The authors recommend consideration of posterior arthroscopic talar body nonunion repair with subtalar arthrodesis as an alternative to the open technique. [1] (10.1002/atn2.70116)
  • [L4] Patients who underwent initial operative treatment had significantly higher Maryland Foot Scores and fewer postoperative wound complications compared with those who underwent initial nonoperative treatment before subtalar arthrodesis. [2] (10.2106/jbjs.i.01267)
  • [L5] Tibiotalocalcaneal fusion is an effective salvage procedure for combined end-stage ankle and subtalar arthrosis and severe planar deformities, providing a stable and painless foot for ambulation. [3] (10.5435/jaaos-d-14-00102)
  • [L4] Subtalar and talonavicular arthrodesis through a medial approach is a valuable and safe alternative that guarantees long-term fusion, prevents non-unions, and significantly reduces wound complications while providing significant correction of fixed deformities. [4] (10.1007/s00402-009-1029-z)
  • [L3] All three operative approaches do not influence the fusion rate and fusion time of the subtalar joint. [5] (10.1186/s13018-014-0115-2)
  • [L3] However, in cases where soft tissue conditions limit safe access to the subtalar joint, satisfactory functional outcomes and pain relief can still be achieved through tibiotalar fusion and subtalar joint immobilization, even without complete fusion. [6] (10.1186/s13018-025-05817-w)
  • [L4] Arthroscopically assisted posterior facet fusion of the subtalar joint is an effective method for management of subtalar arthritis after calcaneal fracture. [7] (10.1016/j.arthro.2008.12.017)
  • [L1] This systematic review found a high rate of union among patients who underwent open subtalar arthrodesis and patients who underwent arthroscopic subtalar arthrodesis. [8] (10.5435/jaaos-d-25-00920)
  • [L5] This unique staged procedure resulted in fair outcomes in terms of AOFAS ankle-hindfoot score and allowed the patient to continue with activities of daily living without complications of infection or collapse requiring additional unplanned procedures. [9] (10.5435/jaaos-d-16-00748)
  • [L5] Surgical treatment, including ostectomy, subtalar arthrodesis, or corrective osteotomy, has a high rate of successful arthrodesis and patient satisfaction. [10] (10.5435/00124635-201101000-00004)
  • [L4] Triple arthrodesis is rarely appropriate and should be performed only according to specific indications. [11] (10.2106/00004623-199303000-00004)
  • [L5] [12] (10.5435/00124635-200409000-00007)
  • [L5] Rigid flatfoot deformities in adolescents have a less predictable clinical course and are associated with various underlying causes, making it critical to investigate the etiology to recommend proper management. [13] (10.5435/jaaos-d-21-00448)
  • [L4] Tibiotalocalcaneal arthrodesis with headless compression screws for the treatment of severe arthropathy of the ankle and subtalar joint is an effective treatment that is minimally invasive and is associated with a short operation time, high fusion rate, low incidence of complications and good postoperative recovery. [14] (10.1186/s13018-016-0425-7)
  • [Paper] Primary subtalar arthrodesis for markedly comminuted Sanders type IV calcaneal fractures yields good mid-term results and is especially indicated when surgical treatment is delayed. [15] (10.1016/j.injury.2009.12.002)
  • [L4] For patients with pain at the site of a failed ankle arthrodesis, conversion to total ankle arthroplasty with the use of a three-component ankle implant is a viable treatment option that provides reliable intermediate-term results. [17] (10.2106/jbjs.i.01301)
  • [L4] Although tibiotalocalcaneal arthrodesis is a salvage procedure, most of the patients benefit from it. [18] (10.1016/s0020-1383(11)70037-7)
  • [L4] Arthroscopic subtalar arthrodesis offers consistent improvement in cases of posttraumatic arthritis following calcaneal fractures, with a union rate similar to published series of open arthrodesis. [19] (10.1016/j.injury.2018.07.022)
  • [L1] Arthroscopic subtalar arthrodesis is an effective treatment option for subtalar joint pathology. [20] (10.1016/j.arthro.2019.11.078)
  • [L4] Use of fully threaded screws, autograft, and two screws compared to a single screw were the factors associated with successful bone union within six postoperative months after subtalar arthrodesis for the posttraumatic arthritis. [21] (10.1186/s13018-023-04040-9)
  • [L4] For surgeons familiar with posterior ankle or subtalar arthroscopy, this minimally invasive debridement and nailing offers superior exposure, high patient satisfaction and lower postoperative morbidity than traditional tibiotalocalcaneal arthrodesis methods; fusion is encouraged by presence of the medullary reaming material at the site of the fusion. [22] (10.1016/j.otsr.2010.03.012)
  • [L4] With the 3-portal technique, a safe and time-efficient arthroscopic subtalar arthrodesis can be performed even in cases with limited subtalar joint space such as in symptomatic talocalcaneal coalition. [23] (10.1007/s00167-009-0795-z)
  • [L5] Triple arthrodesis is a technically demanding procedure that generally involves a prolonged recovery time. [24] (10.5435/00124635-199805000-00007)
  • [L1] No statistically significant differences in union rates, time to union, and postoperative AOFAS of subtalar arthrodesis were found between autografts, allografts, synthetic/artificial grafts, and no grafts. [25] (10.1530/eor-2024-0202)
  • [L3] Joint facet area and fusion of subtalar articular surface were closely related to the severity of flat foot deformity, and Type I and IV were more likely to develop severer flat foot deformity. [26] (10.1186/s12891-021-04872-8)
  • [L4] Total dislocation of the talus results from excessive supination or excessive pronation, with supination being the more frequent mechanism. [27] (10.2106/00004623-195537010-00010)
  • [L4] A primary fusion was obtained in sixteen of eighteen patients. [28] (10.2106/00004623-197456010-00007)
  • [L4] [29] (10.1007/s11999-016-4955-4)
  • [L3] Substantial ankle malalignment, mostly varus deformity, is common in ankles with end-stage osteoarthritis. [30] (10.1007/s11999-014-3960-8)
  • [L4] Tibiotalocalcaneal arthrodesis with a specifically designed retrograde intramedullary nail without formal débridement of the subtalar joint and a choice between open or percutaneous débridement of the ankle is a reliable method to achieve fusion. [31] (10.1097/blo.0b013e31814fb1bb)
  • [L4] The modified Blair arthrodesis provides a normal-appearing foot, produces no shortening, and allows motion to remain at the talonavicular and anterior subtalar joints. [34] (10.2106/00004623-197153070-00004)
  • [L5] Retrograde intramedullary nailing provides a load-sharing fixation device with superior biomechanical properties and is an excellent choice for use in tibiotalocalcaneal arthrodesis. [35] (10.5435/00124635-201201000-00001)
  • [L4] Although early prosthesis failure may occur, survival of the talar body prosthesis can provide satisfactory ankle and foot function for ten to thirty-six years. [36] (10.2106/jbjs.m.00377)
  • [L4] The relief of pain and the restoration of function achieved through effective correction of the severe pes planovalgus deformity account for the satisfactory outcomes. [37] (10.2106/00004623-199911000-00006)
  • [L4] Arthrodesis in patients who have arthrosis and talar osteonecrosis may be successfully accomplished with use of bone graft spanning the affected joints and rigid fixation. [39] (10.2106/00004623-199803000-00010)
  • [L5] [40] (10.2106/jbjs.25.01361)
  • [Paper] LEAP subtalar arthrodesis technique is an efficient way to correct the hindfoot deformity and achieve sound arthrodesis of the subtalar joint. [41] (10.1016/j.eats.2020.10.021)
  • [L4] Associated fractures involving the subtalar or talonavicular joints, open dislocations, and associated injuries requiring immobilization for more than three weeks produced poor results due to pain and limitation of subtalar motion. [42] (10.2106/00004623-198264030-00014)
  • [L5] The anatomy of the subtalar joint presents significant individual variations in the Chinese population, with nearly two thirds of individuals having partly or completely fused anterior and middle facets. [44] (10.1186/s12891-022-05715-w)
  • [L4] A significant increase in subtalar joint plantar flexion was found to be a primary compensation during overground walking and a double heel-rise activity following tibiotalar arthrodesis. [45] (10.2106/jbjs.19.01132)
  • [L4] All patients had fusion at followup radiograms and were able to walk full weight bearing without pain. [50] (10.1016/s0020-1383(13)70067-6)
  • [L4] Management may be on a day-surgery basis, and indications are the same as for open arthrodesis provided deformity can be reduced. [51] (10.1016/j.otsr.2015.06.033)
  • [L4] Given the lack of consensus on treatment, a classification system may be helpful to guide clinical practice. [52] (10.1016/j.injury.2020.04.019)
  • [L3] This is the first study to demonstrate the importance of the morphology of the subtalar joint on the underlying foot posture in vivo. [57] (10.1302/0301-620x.98b4.36059)
  • [L5] This technique is reproducible and safe with regard to the surrounding nerves. [58] (10.1016/j.arthro.2013.04.016)
  • [L5] The study establishes normative data for subtalar joint contact characteristics, showing that contact area ratios and high-pressure zones increase with load, inversion reduces contact area while maintaining high pressures, and increasing fibular load broadens the posterior facet contact area. [62] (10.1002/jor.1100100408)
  • [L4] The study demonstrated the feasibility and contribution of associating fibular shortening osteotomy to tibiotalar arthrodesis, achieving a 97.6% fusion rate and a nonunion rate much lower than reported elsewhere. [63] (10.1016/j.otsr.2017.03.023)
  • [L5] Standard radiographs may fail to detect occult talar neck fractures associated with subtalar dislocation, making fluoroscopy and CT mandatory for evaluation. [64] (10.1016/j.otsr.2016.12.009)
  • [L4] Primary subtalar arthrodesis performed for the treatment of markedly comminuted Sanders type IV calcaneal fractures yields good results even 5 years post-operation. [65] (10.1016/j.injury.2010.11.030)
  • [L4] Satisfactory results were obtained in approximately 75 per cent of twenty-one patients; osseous union was radiographically evident in all but three patients. [66] (10.2106/00004623-198870090-00004)
  • [L4] Triple arthrodesis in older patients relieves or lessens pain; however, because of its technical difficulty and the relatively high rate of postoperative complications, it should be used only as a salvage operation for a painful, unstable foot or a foot that has a fixed, disabling deformity. [67] (10.2106/00004623-199303000-00006)
  • [L5] [68] (10.1002/jor.1100100409)
  • [L4] An aggressive operative approach is recommended for local complications, and early amputation may improve function and reduce burden. [69] (10.1007/s004020050289)
  • [L3] Both ASTA and ISTA techniques are effective procedures for subtalar arthrodesis. [93] (10.1016/j.jisako.2022.10.006)
  • [L4] A new classification system of the talocalcaneal coalition to facilitate operative planning was developed. [96] (10.1186/s12891-021-04567-0)
  • [Letter] With two simple modifications, the indication for arthroscopic posterior subtalar arthrodesis could be extended to primary arthrodesis of Sanders type IV fractures of the calcaneus. [99] (10.1016/j.arthro.2016.08.002)
  • [L4] Calcaneal nonunion is rare but may be more common after conservative treatment; smoking may play a role in its pathophysiology. [102] (10.1007/s00402-007-0516-3)
  • [L4] It allows patient's return to mobility with good to excellent patient satisfaction. [111] (10.1007/s00402-016-2420-1)
  • [L3] Nonunion rates are similar, wound complication rates are lower and outcomes are similar. [112] (10.1016/j.arthro.2023.01.051)
  • [L4] Low complication rates contribute to make this a safe procedure. [113] (10.1007/s00167-015-3548-1)
  • [L4] The results of the Hoke triple arthrodesis are similar to other series regarding deformity correction and non-union rates, with an overall aseptic necrosis rate of 6.5% that has been eliminated by modifying the technique to preserve the artery to the tarsal canal. [114] (10.2106/00004623-197860060-00012)
  • [L1] However, infection risks and heterogeneity across studies highlight the need for standardized protocols and larger controlled trials to optimize patient selection and postoperative management. [115] (10.1186/s13018-025-06077-4)
  • [L3] Clinical outcomes and the proportion achieving union were significantly better in the vascularised group compared with the conventional arthrodesis group. [116] (10.1302/0301-620x.98b3.36154)

See Also

References

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