Surgery for adult acquired flatfoot deformity

Findings by SBU Alert

Version: 1

Technology and target group

Adult acquired flatfoot deformity is a painful condition resulting from the collapse of the longitudinal arch of the foot, frequently caused by the rupture of a large tendon. Problems associated with the condition vary, from a moderate level at early stages to disabling pain accompanied by major impact on the joints in late stages. Mild forms are treated with orthopedic insoles and shoe modifications. Insoles are insufficient therapy for the more severe cases of flatfoot deformity and chronic tendon rupture. At this stage, surgery is the only alternative. Various surgical techniques are used, alone or in combination, for different stages of flatfoot deformity. The target group is estimated to be 600 patients per year in Sweden, primarily women aged 40 to 60 years who are not helped by insoles or shoe modification.

Patient benefit

Currently, there are no controlled studies that compare reconstructive foot surgery with insoles or no treatment. Compiling the results from followup studies shows that about 40 percent of the patients were very satisfied, about 40 percent were satisfied, and about 20 percent were uncertain or dissatisfied with the results of surgery. Several studies have shown a complication rate of surgery between 5 percent and 20 percent. Complications include delayed or no healing in bones, wound infection, and nerve injury.

Economic aspects

There are no studies that present information on what percentage of patients can return to work after surgery. Roughly, the average healthcare costs for reconstructive foot surgery are calculated to be 30 000 SEK per treatment. Since the condition is very debilitating, even moderate treatment effects would represent a major benefit to patients and society.

Scientific evidence

Scientific documentation on the short-term effects of reconstructive foot surgery in adult acquired flatfoot deformity is poor*. There is no* scientific documentation on the long-term effects or the cost-effectiveness of the method.

The research presented in the literature is comprised of retrospective studies or biomechanical studies in a laboratory environment. It is essential for the method to be subjected to further assessment in randomized trials before it is disseminated. Assessments should include economic evaluation.

*This assessment by SBU Alert uses a 4-point scale to grade the quality and evidence of the scientific documentation. The grades indicate: (1) good, (2) moderate, (3) poor, or (4) no scientific evidence on the subject.

This summary is based on a report prepared at SBU in collaboration with Assoc. Prof. Fredrik Montgomery, Malmö University Hospital and has been reviewed by Jan Lidström, MD, Sahlgrenska University Hospital.

The complete report is available in Swedish only.

Alert is a joint effort by the Swedish Council on Technology Assessment in Health Care (SBU), the Medical Products Agency, the National Board of Health and Welfare, and the Federation of Swedish County Councils.

References

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3. Funk DA, Cass JR, Johnson KA. Acquired adult flat foot secondary to posterior tibial-tendon pathology. J Bone Joint Surg Am 1986;68(1):95-102.
4. Harper MC. Talonavicular arthrodesis for the acquired flatfoot in the adult. Clin Orthop 1999;(365):65-8.
5. Hintermann B. Tibialis posterior dysfunction: a review of the problems and personal experience. Foot Ankle Surg 1997;3:61-70.
6. Hintermann B, Valderrabano V, Kunder HP. Lengthening of the lateral column and reconstruction of the medial soft tissue for treatment of acquired flatfoot deformity associated with insufficiency of the posterior tibial tendon. Foot Ankle Int 1999;20(10):622-9.
7. Janis LR, Wagner JT, Kravitz RD, Greenberg JJ. Posterior tibial tendon rupture: classification, modified surgical repair, and retrospective study. J Foot Ankle Surg 1993;32(1):2-13. Review.
8. Kitaoka HB, Patzer GL. Subtalar arthrodesis for posterior tibial tendon dysfunction and pes planus. Clin Orthop 1997;(345):187-94. Review.
9. Mann RA, Thompson FM. Rupture of the posterior tibial tendon causing flat foot. Surgical treatment. J Bone Joint Surg Am 1985;67(4):556-61.
10. Myerson MS. Adult acquired flatfoot deformity. J Bone Joint Surg 1996; 78A:780-92.
11. Phillips GE. A review of elongation of os calcis for flat feet. J Bone Joint
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14. Thordarson DB, Schmotzer H, Chon J. Reconstruction with tenodesis in an adult flatfoot model. A biomechanical evaluation of four methods. J Bone Joint Surg Am 1995;77(10):1557-64.