546859
research-articleXXXX
FASXXX10.1177/1938640014546859Foot & Ankle SpecialistFoot & Ankle Specialist
492
Dec 2014
Foot & Ankle Specialist
〈 Master Surgeon 〉 Endoscopic Adhesiolysis of the Flexor Hallucis Longus Muscle Abstract: Flexor hallucis longus muscle can adhere to the distal tibia after tibial fracture. The patient may complain of deep posteromedial ankle pain, checkrein deformity of the hallux, hallux flexus or development of hallux rigidus. Surgical treatment of release of the FHL muscle or lengthening of the FHL tendon has been proposed. We described an endoscopic approach of release of the FHL muscle from the distal tibia with the advantage of minimal soft tissue dissection. Level of Evidence: Therapeutic Level V: Expert Opinion/Technique Keywords: flexor hallucis longus; checkrein; fracture; compartment syndrome; hallux; trigger toe; hallux malleus; hallux equine
T
metatarsal. The proximal location of the aspect of the ankle joint.1 Adhesion of posteromedial portal can allow more the muscle to the distal tibia can occur proximal instrumentation for the release after distal tibial fracture. The patient of the FHL muscle and proceed to the may complain of deep posteromedial zone 2 FHL tendoscopy8,9,12-16 if needed. ankle pain, checkrein deformity of the 3,4 5,6 hallux, or hallux flexus. Progressive The posterolateral portal is located at the fibrosis at the FHL myotendinous lateral margin of the Achilles tendon just junction can also cause increased loading above the posterosuperior calcaneal of the first metatarsophalangeal joint, tubercle. Usually, there is fibrosis at the thereby leading to hallux rigidus.7 We posterior ankle covering the FHL tendon describe an endoscopic approach of and muscle. First of all, the fibrous tissue release of the FHL muscle from the distal tibia with the advantage of minimal We describe an endoscopic approach soft tissue dissection.
Description of Technique
he flexor hallucis longus (FHL) muscle is the most lateral muscle of the deep compartment of the calf. The muscle originates from the distal half of the fibula, interosseous membrane, and the posterior tibial muscle fascia.1,2 The tendon begins just above the level of the medial malleolus and is located posterolateral to the posterior tibialis and the flexor digitorum longus tendons at the posteromedial
T.H. Lui, MBBS(HK)
“
of release of the FHL [flexor hallucis
longus] muscle from the distal tibia with
the advantage of minimal soft tissue The patient is put on prone position with a dissection.” thigh tourniquet to provide a bloodless operative field. Zone 1 at the lateral part of the distal tibia is FHL tendoscopy was performed with the resected with arthroscopic shaver and the posteromedial and posterolateral 8-11 lateral part of the FHL muscle is then portals. The posteromedial portal is exposed. It is safer to identify the FHL established at the intersection point between the medial margin of the Achilles muscle first rather than the zone 1 FHL tendon because the whitish colored and tendon and a line joining the narrow-sized tendon is easily mixed up sustentaculum tali and the inferior border with the surrounding scar tissue. The of the medial cuneiform and the first
DOI: 10.1177/1938640014546859. Address correspondence to Tun Hing Lui, MBBS(HK), Department of Orthopaedics and Traumatology, North District Hospital, 9 Po Kin Road, Sheung Shui, NT, Hong Kong, SAR, China; e-mail: [email protected]. For reprints and permissions queries, please visit SAGE’s Web site at http://www.sagepub.com/journalsPermissions.nav. Copyright © 2014 The Author(s)
Downloaded from fas.sagepub.com at UNIV OF MICHIGAN on January 6, 2015
vol. 7 / no. 6
Foot & Ankle Specialist
Figure 1.
Figure 2.
Arthoscopic view showing the flexor hallucis longus muscle after resection of the overlying scar tissue.
The flexor hallucis longus (FHL) muscle (A) was released from the distal tibia (B) starting from the lateral edge of the muscle by instruments through the posteromedial portal (arrows). Similarly, the FHL tendon (C) can be released from the posterior talus (D).
tendon can be cut accidentally during resection of the fibrous tissue around it. Moreover, the proximity to the neurovascular bundle may cause damage to the bundle during debridement around the tendon. It is safer to identify the lateral edge of the muscle and trace distally to identify the lateral border of the FHL tendon. The fibrous tissue around the tendon was then resected with the shaver starting from the lateral side of the tendon. The shaver opening should always be pointing at the lateral side with minimal suction in order to avoid neurovascular damage. The resection of the fibrous tissue covering the FHL muscle can be extended medially and proximally to expose the muscle if needed (Figure 1). After identifying the lateral edge of the FHL muscle, the fibrous adhesions between the muscle and the distal tibia and fibula at the level of distal tibiofibular syndesmosis is released by an arthroscopic shaver or a periosteal elevator (Figure 2). When the release is proceeding proximally above the syndesmosis, it should be started from the posterolateral edge of the distal tibia and goes medially so that the muscle can be reflected medially to protect the neurovascular bundle. If release of the muscle lateral to the posterolateral edge of the distal tibia is needed, it should be performed carefully with the shaver
opening under arthroscopic visualization in order to avoid damage to the peroneal artery and veins at the interosseous membrane. However, there is still a potential risk of damage of the communicating and perforating branch of the peroneal artery.17 Any underlying bony prominence of the distal tibia or fibula impinging on the FHL is also resected. In case of screw fixation of the posterior malleolar fracture, the screw head can be exposed and removed under arthroscopic guide. Sometimes, the screw heads may be covered by bone and may not be identified under arthroscopy. The location of the screws can be identified under fluoroscopy. The overlying bone can be removed arthroscopically to expose the screw head. In case of posterior tibial plating, open procedure of release of muscle and removal of implants is more appropriate. Postoperatively, active and passive mobilization of the ankle and hallux is allowed.
Discussion Adhesion of the FHL muscle to the distal tibia can occur after fracture of the
distal tibia4,18 or distal fibula.19 It can be due to entrapment of the FHL in the fracture callus,4,6 scar adhesion of the muscle at the fracture site or as a result of subclinical compartment syndrome of the distal deep posterior compartment3,20-22 of the leg. Surgical treatment of release of the FHL muscle3,5 or lengthening of the FHL tendon20 has been proposed. The distal third and fourth portion of the FHL muscle was always found to be located in a more compressed and deeper compartment.2,22 Surgical release of the FHL muscle has been suggested, as a localized increase in pressure can result in ischemic lesion of the distal part of flexor muscle bellies. As only a small portion of the muscle is involved, there is no retraction of the main muscle belly. The necrotic part of the muscle can become fibrotic and adhere to the surrounding structures. The immobilization of the fibrotic portion during the posttrauma period immobilization can further reduce muscle and tendon mobility. This localized involvement of the muscle itself can explain why release of the FHL
Downloaded from fas.sagepub.com at UNIV OF MICHIGAN on January 6, 2015
493
494
Dec 2014
Foot & Ankle Specialist
muscle and tendon without tendon lengthening can improve the condition.3 In contrast, FHL tendon lengthening by Z-plasty in the foot has also been recommended as the surgical fields are relatively simple and are free of scar tissue and therefore less chance of recurrence of adhesions.10 Moreover, open FHL release at the site of fracture requires a large incision with extensive soft tissue dissection especially around the neurovascular structures.6 However, with the advance of hindfoot endoscopy,10,11 these problems of open release can be alleviated by the endoscopic FHL release. Dissection of the neurovascular bundle is not needed to approach the FHL muscle during the arthroscopic procedure. In order to avoid injury to the posterior tibial neurovascular bundle or its branches during adhesiolysis, the release should be started at the lateral border of the muscle and goes medially. By this way, the neurovascular bundle will be protected by the FHL muscle.23
4. Rosenberg GA, Sferra JJ. Checkrein deformity—an unusual complication associated with a closed Salter-Harris Type II ankle fracture: a case report. Foot Ankle Int. 1999;20:591-594. 5. Burda R, Morochovic R, Kitka M. Hallux flexus—the result of posttraumatic entrapment of the flexor hallucis longus tendon in the tibial fracture site [in Slovak]. Rozhl Chir. 2010;89:466-467. 6. Lee HS, Kim JS, Park SS, Lee DH, Park JM, Wapner KL. Treatment of checkrein deformity of the hallux. J Bone Joint Surg Br. 2008;90:1055-1058. 7. Kirane YM, Michelson JD, Sharkey NA. Contribution of the flexor hallucis longus to loading of the first metatarsal and first metatarsophalangeal joint. Foot Ankle Int. 2008;29:367-377. 8. Lui TH. Arthroscopy and endoscopy of the foot and ankle: indications for new techniques. Arthroscopy. 2007;23:889-902. 9. Lui TH. Flexor hallucis longus tendoscopy: a technical note. Knee Surg Sports Traumatol Arthrosc. 2009;17: 107-110. 10. Ogut T, Ayhan E, Irgit K, Sarikaya AI. Endoscopic treatment of posterior ankle pain. Knee Surg Sports Traumatol Arthrosc. 2011;19:1355-1361.
References 1. Lo LD, Schweitzer ME, Fan JK, Wapner KL, Hecht PJ. MR imaging findings of entrapment of the flexor hallucis longus tendon. AJR Am J Roentgenol. 2001;176:1145-1148.
11. van Dijk CN, Scholten PE, Krips R. A 2-portal endoscopic approach for diagnosis and treatment of posterior ankle pathology. Arthroscopy. 2000;16:871-876.
2. Sassu P, Acland RD, Salgado CJ, Mardini S, Ozyurekoglu T. Anatomy and vascularization of the flexor hallucis longus muscle and its implication in free fibula flap transfer: an anatomical study. Ann Plast Surg. 2010;64:233-237. 3. Fitoussi F, Ilharreborde B, Guerin F, Souchet P, Pennecot GF, Mazda K. Claw
toes after tibial fracture in children. J. Child. Orthop. 2009;3:339-343.
14. Lui TH, Chan KB, Chan LK. Zone 2 flexor hallucis longus tendoscopy: a cadaveric study. Foot Ankle Int. 2009;30:447-451. 15. Lui TH, Chan KB, Chan LK. Cadaveric study of zone 2 flexor hallucis longus tendon sheath. Arthroscopy. 2010;26:808-812. 16. Lui TH. Lateral plantar nerve neuropraxia after FHL tendoscopy: case report and anatomic evaluation. Foot Ankle Int. 2010;31:828-831. 17. Choi SW, Kim HJ, Koh KS, Chung IH, Cha IH. Topographical anatomy of the fibula and peroneal artery in Koreans. Int J Oral Maxillofac Surg. 2001;30:329-332. 18. Berentey G, Tamásy S. Adhesion of the tendon of the m. flexor hallucis longus following tibial fracture [in Hungarian]. Magy Traumatol Orthop Helyreallito Seb. 1973;16:161-168. 19. Leitschuh PH, Zimmerman JP, Uhorchak JM, Arciero RA, Bowser L. Hallux flexion deformity secondary to entrapment of the flexor hallucis longus tendon after fibular fracture. Foot Ankle Int 1995;16:232-235. 20. Hernández-Cortés P, Pajares-López M, Hernández-Hernández MA. Ischemic contracture of deep posterior compartment of the leg following isolated ankle fracture. J Am Podiatr Med Assoc. 2008;98:404-407. 21. Kwiatkowski TC, Detmer DE. Anatomical dissection of the deep posterior compartment and its correlation with clinical reports of chronic compartment syndrome involving the deep posterior compartment. Clin Anat. 1997;10:104-111.
12. Keeling JJ, Guyton GP. Endoscopic flexor hallucis longus decompression: a cadaver study. Foot Ankle Int. 2007;28:810-814.
22. Piper KJ, Yen-yi JC, Horsley M. Missed posterior deep, inferior subcompartment syndrome in a patient with an ankle fracture: a case report. J Foot Ankle Surg. 2010;49:398.e5-8.
13. Lui TH. Endoscopic assisted flexor hallucis tendon transfer in the management of chronic rupture of Achilles tendon. Knee Surg Sports Traumatol Arthrosc. 2007;15:1163-1166.
23. Apaydin N, Loukas M, Kendir S, et al. The precise localization of distal motor branches of the tibial nerve in the deep posterior compartment of the leg. Surg Radiol Anat. 2008;30:291-295.
Downloaded from fas.sagepub.com at UNIV OF MICHIGAN on January 6, 2015
research-articleXXXX
FASXXX10.1177/1938640014546859Foot & Ankle SpecialistFoot & Ankle Specialist
492
Dec 2014
Foot & Ankle Specialist
〈 Master Surgeon 〉 Endoscopic Adhesiolysis of the Flexor Hallucis Longus Muscle Abstract: Flexor hallucis longus muscle can adhere to the distal tibia after tibial fracture. The patient may complain of deep posteromedial ankle pain, checkrein deformity of the hallux, hallux flexus or development of hallux rigidus. Surgical treatment of release of the FHL muscle or lengthening of the FHL tendon has been proposed. We described an endoscopic approach of release of the FHL muscle from the distal tibia with the advantage of minimal soft tissue dissection. Level of Evidence: Therapeutic Level V: Expert Opinion/Technique Keywords: flexor hallucis longus; checkrein; fracture; compartment syndrome; hallux; trigger toe; hallux malleus; hallux equine
T
metatarsal. The proximal location of the aspect of the ankle joint.1 Adhesion of posteromedial portal can allow more the muscle to the distal tibia can occur proximal instrumentation for the release after distal tibial fracture. The patient of the FHL muscle and proceed to the may complain of deep posteromedial zone 2 FHL tendoscopy8,9,12-16 if needed. ankle pain, checkrein deformity of the 3,4 5,6 hallux, or hallux flexus. Progressive The posterolateral portal is located at the fibrosis at the FHL myotendinous lateral margin of the Achilles tendon just junction can also cause increased loading above the posterosuperior calcaneal of the first metatarsophalangeal joint, tubercle. Usually, there is fibrosis at the thereby leading to hallux rigidus.7 We posterior ankle covering the FHL tendon describe an endoscopic approach of and muscle. First of all, the fibrous tissue release of the FHL muscle from the distal tibia with the advantage of minimal We describe an endoscopic approach soft tissue dissection.
Description of Technique
he flexor hallucis longus (FHL) muscle is the most lateral muscle of the deep compartment of the calf. The muscle originates from the distal half of the fibula, interosseous membrane, and the posterior tibial muscle fascia.1,2 The tendon begins just above the level of the medial malleolus and is located posterolateral to the posterior tibialis and the flexor digitorum longus tendons at the posteromedial
T.H. Lui, MBBS(HK)
“
of release of the FHL [flexor hallucis
longus] muscle from the distal tibia with
the advantage of minimal soft tissue The patient is put on prone position with a dissection.” thigh tourniquet to provide a bloodless operative field. Zone 1 at the lateral part of the distal tibia is FHL tendoscopy was performed with the resected with arthroscopic shaver and the posteromedial and posterolateral 8-11 lateral part of the FHL muscle is then portals. The posteromedial portal is exposed. It is safer to identify the FHL established at the intersection point between the medial margin of the Achilles muscle first rather than the zone 1 FHL tendon because the whitish colored and tendon and a line joining the narrow-sized tendon is easily mixed up sustentaculum tali and the inferior border with the surrounding scar tissue. The of the medial cuneiform and the first
DOI: 10.1177/1938640014546859. Address correspondence to Tun Hing Lui, MBBS(HK), Department of Orthopaedics and Traumatology, North District Hospital, 9 Po Kin Road, Sheung Shui, NT, Hong Kong, SAR, China; e-mail: [email protected]. For reprints and permissions queries, please visit SAGE’s Web site at http://www.sagepub.com/journalsPermissions.nav. Copyright © 2014 The Author(s)
Downloaded from fas.sagepub.com at UNIV OF MICHIGAN on January 6, 2015
vol. 7 / no. 6
Foot & Ankle Specialist
Figure 1.
Figure 2.
Arthoscopic view showing the flexor hallucis longus muscle after resection of the overlying scar tissue.
The flexor hallucis longus (FHL) muscle (A) was released from the distal tibia (B) starting from the lateral edge of the muscle by instruments through the posteromedial portal (arrows). Similarly, the FHL tendon (C) can be released from the posterior talus (D).
tendon can be cut accidentally during resection of the fibrous tissue around it. Moreover, the proximity to the neurovascular bundle may cause damage to the bundle during debridement around the tendon. It is safer to identify the lateral edge of the muscle and trace distally to identify the lateral border of the FHL tendon. The fibrous tissue around the tendon was then resected with the shaver starting from the lateral side of the tendon. The shaver opening should always be pointing at the lateral side with minimal suction in order to avoid neurovascular damage. The resection of the fibrous tissue covering the FHL muscle can be extended medially and proximally to expose the muscle if needed (Figure 1). After identifying the lateral edge of the FHL muscle, the fibrous adhesions between the muscle and the distal tibia and fibula at the level of distal tibiofibular syndesmosis is released by an arthroscopic shaver or a periosteal elevator (Figure 2). When the release is proceeding proximally above the syndesmosis, it should be started from the posterolateral edge of the distal tibia and goes medially so that the muscle can be reflected medially to protect the neurovascular bundle. If release of the muscle lateral to the posterolateral edge of the distal tibia is needed, it should be performed carefully with the shaver
opening under arthroscopic visualization in order to avoid damage to the peroneal artery and veins at the interosseous membrane. However, there is still a potential risk of damage of the communicating and perforating branch of the peroneal artery.17 Any underlying bony prominence of the distal tibia or fibula impinging on the FHL is also resected. In case of screw fixation of the posterior malleolar fracture, the screw head can be exposed and removed under arthroscopic guide. Sometimes, the screw heads may be covered by bone and may not be identified under arthroscopy. The location of the screws can be identified under fluoroscopy. The overlying bone can be removed arthroscopically to expose the screw head. In case of posterior tibial plating, open procedure of release of muscle and removal of implants is more appropriate. Postoperatively, active and passive mobilization of the ankle and hallux is allowed.
Discussion Adhesion of the FHL muscle to the distal tibia can occur after fracture of the
distal tibia4,18 or distal fibula.19 It can be due to entrapment of the FHL in the fracture callus,4,6 scar adhesion of the muscle at the fracture site or as a result of subclinical compartment syndrome of the distal deep posterior compartment3,20-22 of the leg. Surgical treatment of release of the FHL muscle3,5 or lengthening of the FHL tendon20 has been proposed. The distal third and fourth portion of the FHL muscle was always found to be located in a more compressed and deeper compartment.2,22 Surgical release of the FHL muscle has been suggested, as a localized increase in pressure can result in ischemic lesion of the distal part of flexor muscle bellies. As only a small portion of the muscle is involved, there is no retraction of the main muscle belly. The necrotic part of the muscle can become fibrotic and adhere to the surrounding structures. The immobilization of the fibrotic portion during the posttrauma period immobilization can further reduce muscle and tendon mobility. This localized involvement of the muscle itself can explain why release of the FHL
Downloaded from fas.sagepub.com at UNIV OF MICHIGAN on January 6, 2015
493
494
Dec 2014
Foot & Ankle Specialist
muscle and tendon without tendon lengthening can improve the condition.3 In contrast, FHL tendon lengthening by Z-plasty in the foot has also been recommended as the surgical fields are relatively simple and are free of scar tissue and therefore less chance of recurrence of adhesions.10 Moreover, open FHL release at the site of fracture requires a large incision with extensive soft tissue dissection especially around the neurovascular structures.6 However, with the advance of hindfoot endoscopy,10,11 these problems of open release can be alleviated by the endoscopic FHL release. Dissection of the neurovascular bundle is not needed to approach the FHL muscle during the arthroscopic procedure. In order to avoid injury to the posterior tibial neurovascular bundle or its branches during adhesiolysis, the release should be started at the lateral border of the muscle and goes medially. By this way, the neurovascular bundle will be protected by the FHL muscle.23
4. Rosenberg GA, Sferra JJ. Checkrein deformity—an unusual complication associated with a closed Salter-Harris Type II ankle fracture: a case report. Foot Ankle Int. 1999;20:591-594. 5. Burda R, Morochovic R, Kitka M. Hallux flexus—the result of posttraumatic entrapment of the flexor hallucis longus tendon in the tibial fracture site [in Slovak]. Rozhl Chir. 2010;89:466-467. 6. Lee HS, Kim JS, Park SS, Lee DH, Park JM, Wapner KL. Treatment of checkrein deformity of the hallux. J Bone Joint Surg Br. 2008;90:1055-1058. 7. Kirane YM, Michelson JD, Sharkey NA. Contribution of the flexor hallucis longus to loading of the first metatarsal and first metatarsophalangeal joint. Foot Ankle Int. 2008;29:367-377. 8. Lui TH. Arthroscopy and endoscopy of the foot and ankle: indications for new techniques. Arthroscopy. 2007;23:889-902. 9. Lui TH. Flexor hallucis longus tendoscopy: a technical note. Knee Surg Sports Traumatol Arthrosc. 2009;17: 107-110. 10. Ogut T, Ayhan E, Irgit K, Sarikaya AI. Endoscopic treatment of posterior ankle pain. Knee Surg Sports Traumatol Arthrosc. 2011;19:1355-1361.
References 1. Lo LD, Schweitzer ME, Fan JK, Wapner KL, Hecht PJ. MR imaging findings of entrapment of the flexor hallucis longus tendon. AJR Am J Roentgenol. 2001;176:1145-1148.
11. van Dijk CN, Scholten PE, Krips R. A 2-portal endoscopic approach for diagnosis and treatment of posterior ankle pathology. Arthroscopy. 2000;16:871-876.
2. Sassu P, Acland RD, Salgado CJ, Mardini S, Ozyurekoglu T. Anatomy and vascularization of the flexor hallucis longus muscle and its implication in free fibula flap transfer: an anatomical study. Ann Plast Surg. 2010;64:233-237. 3. Fitoussi F, Ilharreborde B, Guerin F, Souchet P, Pennecot GF, Mazda K. Claw
toes after tibial fracture in children. J. Child. Orthop. 2009;3:339-343.
14. Lui TH, Chan KB, Chan LK. Zone 2 flexor hallucis longus tendoscopy: a cadaveric study. Foot Ankle Int. 2009;30:447-451. 15. Lui TH, Chan KB, Chan LK. Cadaveric study of zone 2 flexor hallucis longus tendon sheath. Arthroscopy. 2010;26:808-812. 16. Lui TH. Lateral plantar nerve neuropraxia after FHL tendoscopy: case report and anatomic evaluation. Foot Ankle Int. 2010;31:828-831. 17. Choi SW, Kim HJ, Koh KS, Chung IH, Cha IH. Topographical anatomy of the fibula and peroneal artery in Koreans. Int J Oral Maxillofac Surg. 2001;30:329-332. 18. Berentey G, Tamásy S. Adhesion of the tendon of the m. flexor hallucis longus following tibial fracture [in Hungarian]. Magy Traumatol Orthop Helyreallito Seb. 1973;16:161-168. 19. Leitschuh PH, Zimmerman JP, Uhorchak JM, Arciero RA, Bowser L. Hallux flexion deformity secondary to entrapment of the flexor hallucis longus tendon after fibular fracture. Foot Ankle Int 1995;16:232-235. 20. Hernández-Cortés P, Pajares-López M, Hernández-Hernández MA. Ischemic contracture of deep posterior compartment of the leg following isolated ankle fracture. J Am Podiatr Med Assoc. 2008;98:404-407. 21. Kwiatkowski TC, Detmer DE. Anatomical dissection of the deep posterior compartment and its correlation with clinical reports of chronic compartment syndrome involving the deep posterior compartment. Clin Anat. 1997;10:104-111.
12. Keeling JJ, Guyton GP. Endoscopic flexor hallucis longus decompression: a cadaver study. Foot Ankle Int. 2007;28:810-814.
22. Piper KJ, Yen-yi JC, Horsley M. Missed posterior deep, inferior subcompartment syndrome in a patient with an ankle fracture: a case report. J Foot Ankle Surg. 2010;49:398.e5-8.
13. Lui TH. Endoscopic assisted flexor hallucis tendon transfer in the management of chronic rupture of Achilles tendon. Knee Surg Sports Traumatol Arthrosc. 2007;15:1163-1166.
23. Apaydin N, Loukas M, Kendir S, et al. The precise localization of distal motor branches of the tibial nerve in the deep posterior compartment of the leg. Surg Radiol Anat. 2008;30:291-295.
Downloaded from fas.sagepub.com at UNIV OF MICHIGAN on January 6, 2015
