Effects of Medializing Calcaneal Osteotomy on Achilles Tendon Lengthening and Plantar Foot Pressures

Abstract

Posterior tibial tendon insufficiency, or adult acquired flatfoot deformity, involves collapse of the longitudinal arch of the foot with ensuing changes in the bony architecture of the foot as well. While it is generally accepted that a medializing calcaneal osteotomy (MCO) is a very useful treatment for restoring the fallen arch, questions regarding the effects of this procedure upon plantar foot pressures and Achilles tendon length changes need to be answered. This study focuses on changes in plantar foot pressures and Achilles tendon length as the result of performing a MCO. Fourteen fresh-frozen cadaver legs were used to test the effects of MCO on Achilles tendon length changes 2 cm proximal to the Achilles tendon insertion on the calcaneus. Differential variable reluctance transducers were anchored in ventromedial, dorsomedial, dorsolateral, and ventrolateral positions of the Achilles tendon at the aforementioned level. The effects of the MCO on plantar foot pressures were assessed simultaneously using the Tekscan HR Mat. Axial loading (100 lbs) of each specimen was performed in neutral and dorsiflexion (15°). Data were gathered for Achilles tendon length changes and plantar foot pressures for three trials in both the neutral and dorsiflexed positions. A medializing calcaneal osteotomy (1 cm medial translation) was then performed and testing was repeated in the fashion outlined heretofore. Analysis of the data revealed that there was no significant increase in Achilles tendon length as a result of the MCO. The data also showed that average pressure over the first and second metatarsal regions of the forefoot decreased significantly after MCO. At the same time there was a significant increase in average pressure over the medial and lateral aspect of the heel. These findings suggest that the Achilles tendon aids in inversion of the forefoot without undergoing a significant increase in length change of Achilles tendon fibers in any of the regions tested.

Keywords

Flatfoot Deformity Pes Planus Medializing Calcaneal Osteotomy (MCO)Plantar Foot Pressure Achilles Tendon Biomechanics Cadaver Testing Displacement Transducer

Get full access to this article

View all access options for this article.

References

Beals

Pomeroy

Manoli

II : Posterior tendon insufficiency: diagnosis and treatment. J. Am. Acad. Orthop. Surg. 7 (2):112–118, 1999.

Churchill

Sierra

: Posterior tibial tendon insufficiency. Its diagnosis, management, and Treatment. Am. J. Orthop. 27 (5):339–347, 1998.

Cavanagh

Rodgers

Liboshi

: Pressure distribution under symptom-free feet during barefoot standing. Foot Ankle 7 (5):262–276, 1987.

Coughlin

Mann

: Surgery of the Foot and Ankle, 7th ed, Vol. 1, St. Louis, MO, Mosby, 1999, pp. 702–767.

Duckworth

Betts

Franks

Burke

: The measurement of pressures under the foot. Foot Ankle 3:130–141, 1982.

Funk

Cass

Johnson

: Acquired adult flat foot secondary to posterior tibial-tendon pathology. J. Bone Joint Surg. 68-A:95–102, 1986.

Grieve

Rashdi

: Pressures under normal feet in standing and walking as measured by foil pedobarography. Ann. Rheum. Dis. 43:816–818, 1984.

Horton

Myerson

Parks

Park

: Effect of calcaneal osteotomy and lateral column lengthening on the plantar fascia: a biomechanical investigation. Foot Ankle Int. 19:370–373, 1998.

Johnson

: Tibialis posterior tendon rupture. Clin. Orthop. 177:140–147, 1983.

10.

Kitaoka

Luo

: Effect of the posterior tibial tendon on the arch of the foot during simulated weight bearing: biomechanical analysis. Foot Ankle Int. 18:43–46, 1997.

11.

Koch

: Measuring plantar pressure in conventional shoes with the TEKSCAN sensory system. Biomed. Tech. 38:243–248, 1993.

12.

Mann

Thompson

: Rupture of the posterior tibial tendon causing flat foot. Surgical treatment. J. Bone Joint Surg. 67-A:556–561, 1985.

13.

Magnaris

Paul

: In vivo human tendon mechanical properties. J. Physiol. 521:307–313, 1999.

14.

Michelson

Mizel

Jay

Schmidt

: Effect of medial displacement calcaneal osteotomy on ankle kinematics in a cadaver model. Foot Ankle Int. 19:132–136, 1998.

15.

Mosier-LaClair

Pomeroy

Manoli

: Operative treatment of the difficult stage 2 adult acquired flatfoot deformity. Foot Ankle Clin. 6 (1):95–119, 2001.

16.

Mueller

Strube

: Generalizability of in-shoe peak pressure measures using the F-scan system. Clin. Biomech. 11 (3):159–164, 1996.

17.

Muramatsu

Muraoka

: Mechanical properties of tendon and aponeurosis of human gastrocnemius muscle in vivo. J. Appl. Physiol. 90:1671–1678, 2001.

18.

Myerson

: Adult acquired flatfoot deformity. J. Bone Joint Surg. 78-A:780–792, 1996.

19.

Myerson

Fortin

Cunningham

: Changes in tibiotalar contact with calcaneal osteotomy. Trans. Am. Acad. Orthop. Surg. 61:149, 1994.

20.

Myerson

Corrigan

Thompson

Schon

: Tendon transfer combined with calcaneal osteotomy for treatment of posterior tibial tendon insufficiency: a radiological investigation. Foot Ankle Int. 16:712–718, 1995.

21.

Myerson

Horton

Parks

: The effect of calcaneal osteotomy and lateral column lengthening on the plantar fascia: a biomechanical investigation. AOFAS, Winter Specialty Day Meeting, Atlanta, GA; Feb. 1996.

22.

Myerson

Corrigan

: Treatment of posterior tibial tendon dysfunction with flexor digitorum longus tendon transfer and calcaneal osteotomy. Orthopedics 19: 383–388, 1996.

23.

Nyska

Parks

Chu

Myerson

: The contribution of the medial calcaneal osteotomy to the correction of flatfoot deformities. Foot Ankle Int. 22: 278–282, 2001.

24.

Otis

Deland

Kenneally

Chang

: Medial arch strain after medial displacement calcaneal osteotomy: an in vitro study. Foot Ankle Int. 20: 222–226, 1999.

25.

Pomeroy

Manoli

II : A new operative approach for flatfoot secondary to posterior tibial tendon insufficiency: a preliminary report. Foot Ankle Int. 18: 206–212, 1997.

26.

Resnick

Jahss

Choueka

Kummer

Hersch

: Deltoid ligament forces after tibialis posterior tendon rupture: effects of triple arthrodesis and calcaneal displacement osteotomies. Foot Ankle Int. 16: 14–20, 1995.

27.

Steffensmeier

Saltzman

Berbaum

Brown

: Effects of medial and lateral displacement calcaneal osteotomies on tibiotalar joint contact stresses. J. Orthop. Res. 14: 980–985, 1996.

28.

Van Bavel

Drost

: Strain distribution on rat medial gastrocnemius (MG) during passive stretch. J. Biomech. 29: 1069–1074, 1996.

29.

Weinfeld

: Medial slide calcaneal osteotomy. Technique, patient selection, and results. Foot Ankle Clin. 6: 89–94, vii, 2001.