Medical Policy: 07.01.34 

Original Effective Date: December 2006 

Reviewed: July 2020 

Revised: July 2020 



This policy contains information which is clinical in nature. The policy is not medical advice. The information in this policy is used by Wellmark to make determinations whether medical treatment is covered under the terms of a Wellmark member's health benefit plan. Physicians and other health care providers are responsible for medical advice and treatment. If you have specific health care needs, you should consult an appropriate health care professional. If you would like to request an accessible version of this document, please contact customer service at 800-524-9242.


Benefit Application:

Benefit determinations are based on the applicable contract language in effect at the time the services were rendered. Exclusions, limitations or exceptions may apply. Benefits may vary based on contract, and individual member benefits must be verified. Wellmark determines medical necessity only if the benefit exists and no contract exclusions are applicable. This medical policy may not apply to FEP. Benefits are determined by the Federal Employee Program.


This Medical Policy document describes the status of medical technology at the time the document was developed. Since that time, new technology may have emerged or new medical literature may have been published. This Medical Policy will be reviewed regularly and be updated as scientific and medical literature becomes available.



This policy only applies to subtalar arthroereisis (sinus tarsi implant or stent) surgery, a corrective operation to limit range of motion at the subtalar joint in cases of excessive mobility. Arthrodesis describes a surgical fusion of a joint so that the bones grow together. Subtalar arthrodesis (joint fusion) surgery is not addressed in this policy.


Flatfoot (also known as pes planus) is often a complex disorder, with diverse symptoms and varying degrees of deformity and disability - with the common characteristic of partial or total collapse of the arch. Flexible flatfoot is one of the most common types, anatomically described as excessive pronation during weight bearing due to anterior and medial displacement of the talus. (The term flexible means the foot is flat when standing (weight-bearing) and the arch returns when not standing). It may be congenital in nature, or may be acquired in adulthood due to posterior tibial tendon dysfunction.


Conservative treatments include orthotics or shoe modifications, stretching exercises and medication. Various surgical techniques of subtalar arthroereisis have been used in the treatment of patients who have failed conservative treatment.


Arthroereisis is the limitation of excessive movement across the joint. Subtalar arthroereisis is designed to correct the excessive talar displacement and calcaneal eversion by placing an implant in the sinus tarsi, a canal located between the talus and the calcaneus. Subtalar arthroereisis has been performed for a number of years, with a variety of implant designs and compositions. The Maxwell-Brancheau Arthroereisis (MBA) implant is currently favored due to the simple and reversible implantation procedure. The value of subtalar arthroereisis in the management and treatment of flatfoot deformity has not been established.


Alternatives to subtalar arthroereisis include, but may not be limited to, the following:

  • Orthotics
  • Physical therapy
  • Prescription drug therapy
  • Short leg walking cast or brace
  • Surgical procedures including:
  • Arthrodesis
  • Osteotomy


Summary of Evidence

Currently, updated guidelines and randomized high-quality studies are lacking. There has been a lack of consistency with conservative treatments in the available literature where efficacy is shown with the subtalar arthroeisis procedure. Defining the true treatment population in the treatment of childhood and adult flatfoot lack a clear consensus.


Practice Guidelines and Position Statements

National Institue for Clinical Excellence

2009 Guidance from the United Kingdom’s National Institute for Clinical Excellence concluded that current evidence on the safety and efficacy of sinus tarsi implant insertion for mobile flatfoot is inadequate in quality and quantity. Therefore this procedure should only be used with special arrangements for clinical governance, consent and audit, or research.


American College of Foot and Ankle Surgeons (ACFAS)

The ACFAS guideline on adult flatfoot states: "In the adult, arthroereisis is seldom implemented as an isolated procedure. Because of the long-term compensation and adaptation of the foot and adjunctive structures for flatfoot function, other ancillary procedures are usually used for appropriate stabilization. Long-term results of arthroereisis in the adult flexible flatfoot patient have not been established. Some surgeons advise against the subtalar arthroereisis procedure because of the risks associated with implantation of a foreign material, the potential need for further surgery to remove the implant, and the limited capacity of the implant to stabilize the medial column sag directly."


The ACFAS guideline on pediatric flatfoot states: "proponents of this procedure (arthroereisis) argue that it is a minimally invasive technique that does not distort the normal anatomy of the foot. Others have expressed concern about placing a permanent foreign body into a mobile segment of a child’s foot. The indication for this procedure remains controversial in the surgical community."


Regulatory Status

number of implants have been cleared for marketing by the U.S. Food and Drug Administration (FDA) through the 510(k) process and are summarized in Table 1. In general, these devices are indicated for insertion into the sinus tarsi of the foot, allowing normal subtalar joint motion while blocking excessive pronation.


The HyProCure device (extra-osseous subtalar joint implant) from GraMedica is an implantable device indicated for the correction of talotarsal displacement. The device is inserted into the sinus tarsi and thereby reorientates the talocalcaneonavicular joint. The focus and primary diagnosis of the procedure is to properly realign and stabilize the talus of the tarsal mechanism, thereby restoring the talotarsal joint and talotarsal mechanism to normal function and triplane motion.


Other subtalar implants include but are not limited to:

  • Arthrex Prostop and Arthrex Prostop Plus Subtalar Arthroeresis Implant
  • Bioarch Subtalar Arthroereisis Implant
  • BioBLOCK Resorbable Subtalar Implant
  • BioPro Horizon Subtalar Implant
  • Conical Subtalar Implant (CSI)Disco Subtalar Implant
  • Disco Subtalar Implant
  • Futura Angled Subtalar Implant 
  • Futura Conical Subtalar Implant
  • Kalix II
  • Life Spine Subtalar Implant System
  • Lundeen Subtalar Implant
  • Maxwell-Brancheau arthroereisis (MBA) Implant
  • MBA Resorb Implant
  • MetaSurg BioArch Subtalar Implant System
  • Nexa Orthopedics Subtalar Peg
  • Normed Vario Subtalar Screw 
  • OsteoMed Talar-Fit Subtalar Implant System
  • OsteoSpring FootJack Subtalar Implant System
  • Smith Subtalar Arthroereisis Implant
  • SubFix Arthroeisis Implant
  • Sub-Talar Lok Arthroereisis Subtalar Implant System
  • Subtalar Maxwell-Brancheau Arthroereisis (MBA) Implant System
  • Talus of Vilex (TOV) Subtalar Implant
  • Twist Subtalar Implant.


Prior Approval:

Not applicable



Subtalar arthroereisis as a stand alone or in a combination surgical procedure, is considered investigational.


Data in the published medical literature are inadequate to permit scientific conclusions. One limitation of the published data is the lack of long-term outcomes, particularly important since the procedure is often performed in growing children. Another limitation is the lack of controlled studies comparing use of the implants with other surgical procedures (alone or in combination).


Currently there are not published control trials comparing talotarsal stabilization with extra-osseous subtalar joint implant and nonsurgical treatment or alternative surgical techniques. There are currently no randomized, prospective controlled studies that evaluate the safety and efficacy of subtalar arthroereisis in combination with other surgical procedures. Limitations of the published data is the lack of longterm outcomes, particularly important since the procedure is often performed in growing children, and the difficulty in separating the effect of this procedure from that of other adjunctive treatments. In addition, some publications report high rates of complications and implant removal. Extra-osseous subtalar joint implant is considered investigational.


Procedure Codes and Billing Guidelines:

To report provider services, use appropriate CPT* codes, Modifiers, Alpha Numeric (HCPCS level 2) codes, Revenue codes, and/or diagnosis codes.

  • S2117 Arthroereisis, subtalar
  • 0335T Insertion of sinus tarsi implant
  • 0510T Removal of sinus tarsi implant
  • 0511T Removal and reinsertion of sinus tarsi implant
  • 28899 Unlisted procedure, foot or toes


Selected References:

  • Nelson SC, Haycock DM, Little ER. Flexible flatfoot treatment with arthroereisis: radiographic improvement and child health survey analysis. J Foot Ankle Surg. 2004;43(3):144-55. PubMed 15181430 [PMID].
  • Husain ZS, Fallat LM. Biomechanical analysis of Maxwell-Brancheau arthroereisis implants. J Foot ankle Surf. 2002 Nov-Dec;41(6):352-8.
  • Needleman RL. Current Topic Review: Subtalar Arthroereisis for the Correction of Flexible Flatfoot. Foot & Ankle Int. 2005 April;26(4):336-346.
  • Vora AN, Tien TR, Parks BG. Correction of moderate and severe acquired flexible flatfoot with medializing calcaneal osteotomy and flexor digitorum longus transfer. J Bone & Joint Sug. AM. 88:1726-1734, 2006.
  • Harris EJ, Vanore JV, Thomas JL, Kravitz SR, Mendelson SA, Mendicino RW, Silvani SH, Gassen SC; Clinical Practice Guideline Pediatric Flatfoot Panel. Diagnosis and treatment of pediatric flatfoot. J Foot Ankle Surg. 2004. Nov-Dec;43(6):341-73.
  • Lee MS, Vanore JV, Thomas JL, Catanzariti AR, Kogler G, Kravitz SR, Miller SJ, Gassen SC. Diagnosis and treatment of adult flatfoot. J Foot Ankle Surg 2005 Mar-Apr;44(2):78-113.
  • Needleman RL, A surgical approach for flexible flatfeet in adults including a subtalar arthroeresis with the MBA sinus tarsi implant. Foot Ankle Int. 2006 Jan;(1)9-18.
  • ECRI. Institute Subtalar Arthroereisis Implants for Treatment of Flexible Flatfoot Deformity. Plymouth Meeting (PA): ECRI Institute; 2006 Dec 28. 8p. [ECRI hotline response.
  • Saxena A, Nguyen A, Preliminary radiographic findings and sizing implications on patients undergoing bioabsorbable subtalar arthroeresis. J Foot Ankle Surg. 2007 May-June;46(3)175-80.
  • National Institute for Health and Clinical Excellence (NICE). Sinus tarsi implant insertion for mobile flatfoot. Interventional Procedure Guidance 305. July 2009.
  • Metcalfe SA, Bowling FL, Reeves ND. Subtalar joint arthroereisis in the management of pediatric flexible flatfoot: a critical review of the literature. Foot Ankle Int. 2011 Dec;21(12):1127-39.
  • ECRI. Subtalar Arthroereisis Implants for Treatment of Flexible Flatfoot. Plymouth Meeting (PA): ECRI Institute 2011 July 19. [Hotline Response].
  • Gross C, Erickson BJ, Adams SB, Parekh SG. Ankle arthrodesis after failed total ankle replacement: A systematic review of the literature. Foot Ankle Spec. 2015;8(2):143-151.
  • Chong DY, Macwilliams BA, Hennessey TA, et al. Prospective comparison of subtalar arthroereisis with lateral column lengthening for painful flatfeet. J Pediatr Orthop B. Jul 2015;24(4):345-353. PMID 25856275
  • Harris EJ, Vanore JV, Thomas JL, et al. Clinical Practice Guideline Pediatric Flatfoot Panel:American College of Foot and Ankle Surgeons (ACFAS). Diagnosis and treatment of pediatric flatfoot. J Foot Ankle Surg. Nov-Dec 2004;43(6):341-373. PMID 15605048
  • Lee MS, Vanore JV, Thomas JL, et al. Clinical Practice Guideline Adult Flatfoot Panel: American College of Foot and Ankle Surgeons (ACFAS). Diagnosis and treatment of adult flatfoot. J Foot Ankle Surg. Mar-Apr 2005;44(2):78-113. PMID 15768358
  • Sullivan MP, Firoozabadi R. Current management of talar fractures. Instr Course Lect. 2017;66:39-49.
  • Bernasconi, A., Lintz, F., Sadile, F. The role of arthroeisis of the subtalar joint for flatfoot in children and adults. EFFORT Open Rev 2017; 438-446. 
  • Walley KC, Greene G, Hallam J, et al. Short- to mid-term outcomes following the use of an arthroereisis implant as an adjunct for correction of flexible, acquired flatfoot deformity in adults. Foot Ankle Spec. 2018 Apr 1.
  • Caravaggi P, Lullini G, Berti L, et al. Functional evaluation of bilateral subtalar arthroereisis for the correction of flexible flatfoot in children: 1-year follow-up. Gait Posture. 2018;64:152-158. 
  • Indino C, Villafañe J, et. al. Effectiveness of subtalar arthroereisis with endorthesis for pediatric flexible flat foot: a retrospective cross-sectional study with final follow up at skeletal maturity. Foot Ankle Surg. 2018 Dec 21. pii: S1268-7731(18)30505-8. doi: 10.1016/j.fas.2018.12.002
  • Viladot Voegeli A, Fontecilla Cornejo N, Serrá Sandoval JA, Alvarez Goenaga F, Viladot Pericé R. Results of subtalar arthroereisis for posterior tibial tendon dysfunction stage IIA1. Based on 35 patients. Foot Ankle Surg. 2018 Feb;24(1):28-33. 


Policy History:

  • July 2020 - Annual Review, Policy Revised
  • July 2019 - Annual Review, Policy Revised
  • July 2018 - Annual Review, Policy Revised
  • July 2017 - Annual Review, Policy Revised
  • July 2016 - Annual Review, Policy Renewed
  • August 2015 - Annual Review, Policy Renewed
  • September 2014 - Annual Review, Policy Revised
  • October 2013 - Interim Review, Policy Revised
  • May 2013 - Annual Review, Policy Renewed
  • May 2012 - Annual Review, Policy Renewed
  • June 2011 - Annual Review, Policy Renewed

Wellmark medical policies address the complex issue of technology assessment of new and emerging treatments, devices, drugs, etc.   They are developed to assist in administering plan benefits and constitute neither offers of coverage nor medical advice. Wellmark medical policies contain only a partial, general description of plan or program benefits and do not constitute a contract. Wellmark does not provide health care services and, therefore, cannot guarantee any results or outcomes. Participating providers are independent contractors in private practice and are neither employees nor agents of Wellmark or its affiliates. Treating providers are solely responsible for medical advice and treatment of members. Our medical policies may be updated and therefore are subject to change without notice.


*CPT® is a registered trademark of the American Medical Association.