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The Journal of Foot & Ankle Surgery 52 (2013) 298–302

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The Journal of Foot & Ankle Surgery

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Lateral Release in Hallux Valgus Deformity: From Anatomic Study to Surgical Tip

Rastislav Hrom�adka, MD, PhD 1,2, Vladislav Bart�ak, MD, PhD 1, Ji�r�ı Bek, MD1, Stanislav Popelka Jr., MD 3,Jana Bedn�a�rov�a 2, Stanislav Popelka, MD, PhD 1

1 First Orthopaedic Clinic, First Faculty of Medicine, Charles University, Prague, Czech Republic2 Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic3 Second Faculty of Medicine, Charles University, Prague, Czech Republic

a r t i c l e i n f o

Level of Clinical Evidence: 4Keywords:hallux valguslateral release of hallux valgusreconstruction of forefootsoft procedure of hallux valgustenotomy of adductor hallucis muscle

Financial Disclosure: Supported by the ProjeRepublic) for Conceptual Development of Research O

Conflict of Interest: None reported.Address correspondence to: Rastislav Hrom�adka,

1.LF UK a FN Motol, V �Uvalu 84, Prague 5, 15006 CzeE-mail address: rastho@gmail.com (R. Hrom�adka)

1067-2516/$ - see front matter � 2013 by the Americhttp://dx.doi.org/10.1053/j.jfas.2013.01.003

a b s t r a c t

The important part of hallux valgus deformity operations, especially in the case of an incongruent joint, is therelease of the soft tissue on the lateral side of the first metatarsophalangeal joint. The purpose of the presentanatomic study was, with preparation of the lateral structures of the joint and lateral conjoined tendon, toprovide a background for a surgical tip of the release of the joint for an additional metatarsal osteotomy. Forthe present study, we used 30 specimens (15 left and 15 right) from 19 cadavers at the Institute of Anatomy,First Faculty of Medicine, Charles Faculty (Prague, Czech Republic). Only specimens that met the criteria ofhallux valgus were included in the present study. The technique was based on the incision of the lateralsesamoid ligament and partial tenotomy of the lateral conjoined tendon from the first interdigital web space.The release was done gradually with supination and abduction of the big toe to achieve the smallest size of thetenotomy. The median of the tenotomy size of the conjoined tendon was 6.5 (range 5 to 14) mm. The mediansize of the conjoined tendon in the frontal plane just ventral to the sesamoid bone was 10.6 (range 8 to14) mm. The technique of the release, in which the big toe was abducted and supinated, can minimize the sizeof the lateral conjoined tendon release and can minimize the possibility of a postoperative deformity.

� 2013 by the American College of Foot and Ankle Surgeons. All rights reserved.

Operations of the hallux valgus are the most common proceduresin orthopedic surgery. The important part of these procedures, incases of an incongruent joint, is the lateral release of the soft tissue ofthe first metatarsophalangeal joint. These procedures have beenroutinely used since the 1920s and 1930s (1–3).

The pathomechanics of the deformity are well known, and animportant part is the imbalance of the first metatarsophalangeal joint(MTP) stabilizers. In 1923, Silver (3) published the basic anatomy ofthe deformity according to the mechanical imbalances of the flexorsand extensors. Silver noted the basic role of the adductor hallucismuscle and its lateral conjoint tendon, whose action naturally tendsto increase the deformity. The lateral part of the joint has undergonesufficient structural adaptation to the deformed position, and thejoint capsule will also be stretched. There is no doubt that the positionand tension of the lateral structures play a role in the resistance of thedeformity (1–4).

The success of the correction depends on a balance between thelateral and medial conjoint tendons of the first MTP joint. The

ct (Ministry of Health, Czechrganization 00064203.

MD, PhD, 1. Ortopedick�a Klinika,ch Republic..

an College of Foot and Ankle Surgeon

balance usually must achieved by a suitable combination of a softtissue procedure and an osteotomy. The techniques of lateral releaseas a part of the procedure were designed to avoid the associatedcomplications. The most common complications have been reportedto be recurrence of hallux valgus, development of a hallux varus,and cock-up deformity of the toe. Various dynamic overcorrectionand cock-up deformities can result from excessive release of thelateral conjoined tendon, especially the part of the tendon thatbelongs to the lateral portion of the flexor hallucis brevis muscle(FHB) (5–12).

Several investigators have studied the attachment of the conjoinedtendon to describe its structural changes in hallux valgus deformitywith regard to the release (13–15). Several techniques and tips havebeen previously published for the release of shortened parts on thelateral side of the first MTP joint. Coughlin and Smith (16) releaseda part of the adductor hallucis of the lateral conjoined tendon from thedorsal aspect of the lateral sesamoid and then sutured its stump to theproximal part of the first MTP joint capsule. The stump and suturereinforced the lateral aspect of the joint to help prevent postoperativehallux varus deformity. Barouk (17) used a partial release of theconjoined tendon distal to the lateral sesamoid and preserved thecollateral ligament of the first MTP joint to prevent dynamic over-correction. Both investigators released the ligament of the lateralsesamoid to allow its repositioning.

s. All rights reserved.

R. Hrom�adka et al. / The Journal of Foot & Ankle Surgery 52 (2013) 298–302 299

Our study was an anatomic study of the adductor hallucis muscleattachment and its lateral conjoint tendon and the lateral part of thefirst MTP joint capsule. A surgical tip is proposed to minimize thepossibility of a complete tenotomy and prevent postoperative defor-mity of the big toe position. We evaluated the level of the releasenecessary to correct the deformity on cadavers using the proposedtechnique and prepared the joint for an additional metatarsalosteotomy.

Fig. 2. Dorsolateral view of first metatarsophalangeal joint with hallux valgus deformityand lateral release of the deformity. Enlargement shows longitudinal incision releasingligament of the lateral sesamoid (LLS) and, in some cases, the lateral collateral ligament(LCL) and partial tenotomy of the lateral conjoined tendon (Lct). The conjoined tendonconsists of the lateral head of the flexor hallucis brevis (lh), oblique head (oh), andtransverse head (th) of the adductor hallucis muscle. DTML, deep transverse metatarsalligament.

Methods

For the purpose of the present study, we used 30 specimens of thelower extremities (15 left and 15 right) from 19 fresh cadavers at theInstitute of Anatomy, First Faculty of Medicine, Charles Faculty(Prague, Czech Republic). Only the 30 specimens that met the criteriaof hallux valgus were included in the present study. All cadavers hada hallux valgus angle greater than 15�. Precise measurements of theresulting angle were performed during the first phase of the dis-section while simulating the forefoot weightbearing. Cadavers withsevere deformities of the ankle joint or the midfoot and those withscars of the forefoot were excluded from the present study.

The preparations during dissection were done by us, and manip-ulation of the structures was minimal, allowing measurements of thestructures in their original positions.

In the first phase, the first interdigital web space was dissectedusing a longitudinal dorsal approach. The skin incision was about10 mm lateral to the tendon of the extensor hallucis longus muscle.The first dorsal digital nerve in the subcutaneous tissue was preparedand pulled medially. The space was then opened with a retractor, andthe blunt part of a scalpel was used to prepare the lateral part of thefirst MTP joint.

The hood ligament (4), which covers the lateral part of the joint(Fig. 1), was cut longitudinally in a transversal plane and pulledmedially. The 2 main ligaments of the lateral part of the joint capsulewere identified and prepared. We defined the lateral collateralligament, whichwent from themost lateral part of the first metatarsalhead to the lateroplantar part of the proximal phalanx (Fig. 2). Theligament of the lateral sesamoid was defined as fibers of the capsule,which pass from the most lateral part of the metatarsal head(epicondyle) toward the lateral margin of the lateral sesamoid bone(Fig. 2).

Fig. 1. Dorsolateral view of first metatarsophalangeal joint with hallux valgus deformity.Hood ligament (HL) covers the joint on lateral side with fibers oriented in coronal plane.The ligament holds tendons of the extensor hallucis longus (EHL) and extensor hallucisbrevis (EHB) muscles as a retinaculum.

The structures around the sesamoid bonewere then dissectedwithRochester-Pean forceps. The lateral conjoined tendon was identifiedbetween the sesamoid and its attachment to the lateroplantar side ofthe proximal phalanx. The transverse and oblique head of theadductor hallucis and the lateral head of the flexor hallucis brevis andthe attachment to the posterior part of the sesamoid bone wereprepared. Finally, the deep transverse intermetatarsal ligament and itsattachment into the lateral part of the sesamoid bone were identified.

In the second phase, the lateral release was performed (Fig. 2). Thegoal of the release was to reposition the lateral sesamoid bone andcorrect the deformity in the first MTP joint. The repositioning andcorrection were evaluated during dissection by 2 observers usingtechniques similar to those used during an operation of a forefoot. Theposition of the big toe was observed during simulated weightbearing,with force applied on the sole and to adduct the first metatarsal boneto decrease the first intermetatarsal angle. The physiologic position ofthe big toe (<15� of adduction) during simulated weightbearing wasconsidered a satisfactory result of the release. We also pulled the bigtoe into abduction, and a satisfactory result was 5� of overcorrection(5� of abduction of the big toe) and the lateral sesamoid bonepositioned on the plantar side of the first metatarsal head.

The release technique consisted of 2 incisions, similar to thatproposed by Barouk (17). The first incision was always between thesesamoid bone and the lateral side of the first metatarsal head in thesagittal plane. The incision released the sesamoid ligament and thesesamoid bone. The second incisionwas at the level of the joint gap inthe frontal plane, and partial tenotomy of the lateral conjoined tendonwas performed (Fig. 2). The primary goal of our modification was topull and turn the big toe into abduction and supination during thetenotomy of the conjoined tendon. If the release was not satisfactory,we continued with release of the adductor hallucis along the sesa-moid bone. If repositioning or rotation of the sesamoid bone was notsatisfactory, the transverse intermetatarsal ligament was dissected.

In the third phase, an additional dissection was performed fromthe plantar side of the first MTP joint and the first intermetatarsal webspace. A flexible gauge was used to measure the curved surface of thetendon (see the “Results” section). Using a flexible gauge and a plantaranatomic approach, we evaluated the size of the conjoined tendontenotomy, its tenotomy, and possible damage to the neurovascularstructures below the adductor muscle and transverse intermetatarsalligament.

Fig. 4. Frontal plane section of proximal phalanx base. b, extent of the released part of theconjoined tendon; c, extent of the lateral conjoined tendon in frontal plane; C, jointcapsule; EHB, extensor hallucis brevis muscle; EHL, extensor hallucis longus muscle; FHL,flexor hallucis longus muscle; HL, hood ligament; Lct, lateral conjoined tendon; Mct,medial conjoined tendon.

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Results

A total of 30 lower extremities from 19 cadavers were dissectedand measured. The group consisted of 67% females (20 specimens)and 33% males (10 specimens). The median deviation of hallux valguswas 36� (range 17� to 53�).

Structural abnormalities from the typical morphology of thedeformity were not found in any case. The lateral conjoined tendon isformed from the lateral head tendon of the flexor hallucis brevis andthe transversal and oblique head tendons of the adductor hallucis. All3 parts of the conjoined tendon come together just before thesesamoid bone; however, the transversal head is minimally involvedin its formation. The lateral sesamoid is embedded into the conjoinedtendon just below the first metatarsal head but does not fill thetendon in its entirety; it is mainly on the lateral side, and a part of theoblique head of the adductor passes around it (Fig. 3). The role of thetransversal head in forming the conjoined tendon is minimal, withonly a small ventral part of the head joining the tendon. The dominantpart of the transversal head passes through the fibers of the obliquehead toward the plantar side of the first MTP joint capsule and sheathof the flexor hallucis longus tendon.

The transverse metatarsal ligament, which connects the lateralsesamoid and plantar pads of the metatarsophalangeal joints, wasattached to the plantolateral side of the lateral sesamoid bone in allspecimens.

The lateral head of the flexor hallucis brevis connects the obliquehead in its course below the first metatarsal bone. In 24 cases (77%),we were not able to clearly separate the oblique head from thelateral fibers of the flexor hallucis brevis on the posterior margin ofthe lateral sesamoid bone. The transverse head of the adductor andlateral margin of the oblique head were clearly identified in all30 specimens.

The lateral conjoint tendon is attached to the lateroplantar side ofthe proximal phalanx to its lateral tubercle. We did not find anyseparate slip of the adductor with a solitary attachment. The mediansize of the part (Fig. 3, marked with “a”) that passes the lateralsesamoid was 4.4 (range 3 to 6) mm. The median size of the lateralconjoined tendon (Fig. 4) just ventral to the lateral sesamoid bonewas10.6 (range 8 to 14) mm. The median size of the tenotomy, whichappropriately corrected the adduction deformity of the big toe in ourgroup of specimens (Fig. 4), was 6.5 (range 5 to 14) mm.

Fig. 3. Frontal plane section of first and second metatarsal heads. a, extent of part ofadductor hallucis muscle, which runs past the lateral sesamoid; AbdH, abductor hallucismuscle; AddH, adductor hallucis muscle; C, joint capsule; DTML, deep transverse meta-tarsal ligament; EHB, extensor hallucis brevis muscle; EHL, extensor hallucis longusmuscle; FHL, flexor hallucis longus muscle; HL, hood ligament.

The deformity was treated by partial tenotomy of the conjoinedtendon and release of the lateral sesamoid ligament in 27 cases (90%).In 3 cases (10%), it was necessary to perform a tenotomy of the entiretendon to correct the deviation, with an adduction of 48�, 50�, and53�. The release of the transverse metatarsal ligament was done onlyin these 3 cases.

Discussion

The release of the structures on the lateral side of the first meta-tarsophalangeal joint is an important part of operations to treat halluxvalgus deformity in the case of an incongruent joint. Understandingthe pathologic anatomy is essential for the surgical technique andcorrection of the deformity. The lateral conjoined tendon of theadductor hallucis and lateral head of the flexor hallucis brevis muscleplays a major role in its development. Attached to the lateroplantarside of the proximal phalanx, the tendon influences the big toe inadduction and pronation (3,4). The release plays a major role in therestoration of the joint soft tissue imbalance (1,3,16–23).

In our study, we were successful in identifying the lateralconjoined tendon and both heads of the adductor hallucis muscleusing a dorsal interdigital approach. The structures were more visibleand could more easily be identified in an opened first web space witha deformity than in the case of a physiologically normal forefoot. Thisis especially true when the lateral conjoined tendon is distended fromits original position on the lateroplantar side of the first MTP joint tothe lateral position and when its rotation correlates with adduction ofthe big toe. The attachment of the lateral head of the FHB and theoblique head of adductor hallucis muscle to the dorsal side of thelateral sesamoid can also be more easily identified. The lateral head ofthe FHB can be easier to isolate; however, it can also be easilydamaged because the muscle is displaced from its original positionbeneath the first metatarsal bone. Our results support the idea thatthe more visible the structures, the more difficult it is to achievecorrection of the deformity during an operation and to perform theappropriate level of release.

Fig. 5. Frontal plane section of proximal phalanx base. An inappropriate tenotomy of the lateral conjoined tendon can result from a pronated position of big toe (left, white arrow).Different extent of tenotomy in abduction and supination of the big toe (right, black arrows).

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Any independent separate slip of the adductor hallucis was notfound in our study, but in all cases, a part of the oblique head passedaround the lateral sesamoid to form the conjoined tendon. Duringontogenesis of a human foot, the lateral conjoint tendon is formedfrom 3 separates parts: the lateral head of the flexor hallucis brevis,the oblique head of the adductor, and the interosseus plantaris hal-lucis muscle (24). The interosseus muscle later adheres to the obliquehead of the adductor. Theoretically, if the separate slip is present, itwill correspond to the interosseus plantar hallucis muscle as anontogenetic variation. In physiologic cases, the tendon of the inter-osseus muscle forms the part of the conjoined tendon that passesaround the sesamoid. The transverse head of the adductor does notbelong to the oblique head during ontogenesis and connects to it ina later phase of foot development.

There is no doubt that the structures of the joint must be adjustedto correct the imbalance of the incongruent joint. The basic objectiveis to determine how to release those structures to correct the defor-mity safely and prevent postoperative deformities such as halluxvarus, cock-up deformity, and hallux valgus recurrence (5,7–12).

Owens and Thordarson (14) described the clinical aspects of therelease in their anatomic study of cadavers. They used a dorsal directapproach to structures that are stretched on the lateral side of thejoint. During their study, they identified the insertion of the adductorhallucis posterior to the sesamoid bone and the gap between themedial part of the muscle and the lateral head of the FHB. In 9 of42 specimens, roughly 50% of the insertion was released. The iden-tification of the gap between the muscles is important for this type ofrelease when the surgeon must release the entire adductor hallucisfrom the dorsal part of the sesamoid. A possible complication isextensive release of the structures that are attached posterior to thesesamoid.

The gap is not important in the technique when the surgeonperforms a partial tenotomy of the conjoint tendon anterior to thelateral sesamoid (17); however, a possible pitfall of the technique canbe in the amount of the release. In severe deformities, the conjoinedtendon is turned from a plantolateral position with the sesamoid toa lateral position and the big toe is pronated. If the tenotomy is per-formed with the big toe in the pronated position, an inappropriatetenotomy could result. We recommend supinating and pulling the bigtoe into abduction during the tenotomy (Fig. 5). The supination turnsthe insertion of the lateral conjoined tendon below the proximalphalanx and thus protects the part of the tendon that belongs to the

lateral head of the FHB. The possibility of an extensive or completerelease is thus minimized.

The success of the operation and a satisfactory outcome dependson the balance of the lateral andmedial conjoint tendons. The balanceof the joint usually must be achieved by a suitable combination ofa soft tissue procedure and an osteotomy; however, only the lateralrelease to correct the joint deformity was used in our anatomic study.The correction of both sesamoids from the bone and distal soft tissueprocedure is important to the outcome and for painless walking. Theposition of the sesamoids can be evaluated, for example, using thetibial sesamoid–second metatarsal distance (25).

We believe that the technique of partial tenotomy is suitable in thecase of a subluxated first MTP joint to adjust the joint imbalance butthat it should be combined with the bone procedure. In 3 cases, thecorrection was not achieved, even with total tenotomy of the lateralconjoined tendon, andwe believe that resulted from the absence of anosteotomy.

Barouk (17) proposed not releasing the lateral collateral ligament,which protects the joint from postoperative dynamic overcorrection.We did not intentionally release it, except in 3 cases that requiredtotal tenotomy; however, it was unintentionally released in 78% of thecases during the first phase of the release. The ligament is enhanced inthe part of the joint capsule at the interval between the most lateralpart of the head and plantar to the lateral tubercle of the proximalphalanx. If the first incision in the transversal plane reaches the levelof the joint gap, the ligament will have already been released (Fig. 2).We believe it is difficult to release the joint without the incision ina part of the collateral ligament. The rest of the joint capsule canprotect the joint from dynamic postoperative overcorrection ifa longitudinal incision of the capsule is used.

Only an adequate release can correct the deformity and preventthe aforementioned postoperative complications. The tip is in theposition of the big toe during the performance of the lateral release.We suggest that in the first phase, for an appropriate release, that theincision should be made in the joint capsule in the sagittal planebetween the lateral sesamoid and the head of first metatarsal bone,such as was proposed by Barouk (17). The incision ventrally shouldopen the joint cavity to the level of the joint gap.

In the second phase, when partial tenotomy of the lateralconjoined tendon is done, the incision should be performed ina frontal plane at the level of joint gap. We recommend performingthe tenotomy for up to 6 to 7 mm. This part of the procedure should

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also be performed gradually, and the big toe should be pulled intoabduction and supinated to achieve a suitable tenotomy. Thesupinated proximal phalanx will protect the part of the conjoinedtendon that belongs to the lateral head of the flexor hallucis brevis.We think the stretched tendon can even protect the neurovascularbundle on the plantolateral side of the conjoined tendon. The tenot-omy is performed with a scalpel blade, usually from medially tolaterally (Fig. 5). The different consistency of the tissue of thestretched tendon and the fat tissue with the neurovascular bundleguarantee a lower possibility of damage with a precise surgicaltechnique. We did not detect any damage to these structures in ourgroup of specimens.

Acknowledgment

We want to thank Ms J. C. Cortese for her editing of our report.

References

1. Hiss JM. Hallux valgus. Am J Surg 9:51, 1931.2. McBride ED. A conservative operation for bunions. J Bone Joint Surg 10:735–739,

1928.3. Silver D. The operative treatment of hallux valgus. J Bone Joint Surg 5:225–232,

1923.4. Haines RW, McDougall A. The anatomy of hallux valgus. J Bone Joint Surg Br

36:272–293, 1954.5. Coughlin MJ. Why bunion surgery fails. Contemp Orthop 23:27, 1991.6. Coughlin MJ. Surgeonsdhallux valgus. J Bone Joint Surg Am 78:932–966, 1996.7. Hawkins FB. Acquired hallux varus: cause, prevention and correction. Clin Orthop

Relat Res 76:169–176, 1971.

8. Hawkins FB, Mitchell CL, Hedrick DW. Correction of hallux valgus by metatarsalosteotomy. J. Bone Joint Surg. Am 27:387–394, 1945.

9. McBride ED. Hallux valgus, bunion deformity: its treatment in mild, moderate andsevere stages. J Int Coll Surg 21:99–105, 1954.

10. McBride ED. The McBride bunion hallux valgus operation. J Bone Joint Surg49A:1675–1683, 1967.

11. Miller JW. Acquired hallux varus: a preventable and correctable disorder. J BoneJoint Surg Am 57:183–188, 1975.

12. Turner RS. Dynamic post-surgical hallux varus after lateral sesamoidectomy:treatment and prevention. Orthopedics 9:963–969, 1986.

13. Lin I, Bonar SK, Anderson RB, Davis WH. Distal soft tissue release using direct andindirect approaches: an anatomical study. Foot Ankle Int 17:458–463, 1996.

14. Owens S, Thordarson DB. The adductor hallucis revisited. Foot Ankle Int22:186–191, 2001.

15. Sarrafian SK. Anatomy of Foot and Ankle, JB Lippincott, Philadelphia, 1983.16. Coughlin MJ, Smith BW. Hallux valgus and first ray mobility: surgical technique.

J Bone Joint Surg Am 90:153–170, 2008.17. Barouk LS. Forefoot Reconstruction, pp. 19–20, Springer, Paris, 2004.18. DuVries HL. Surgery of the Foot, pp. 381–388, CV Mosby, St. Louis, 1959.19. Joseph B, Chacko V, Abraham T, Jacob M. Pathomechanics of congenital and

acquired hallux varus: a clinical and anatomical study. Foot Ankle 8:137–143, 1987.20. Mann RA, Coughlin MJ. Hallux valgusdetiology, anatomy, treatment and surgical

considerations. Clin Orthop 157:31–41, 1981.21. Mann RA, Coughlin MJ. Adult hallux valgus. In: Surgery of the Foot and Ankle, pp.

167–296, edited by RA Mann, MJ Coughlin, Mosby-Year Book, St. Louis, 1993.22. Mann RA, DuVries HL. Major surgical procedures for disorders of the forefoot. In:

DuVries’ Surgery of the Foot, ed 4, p. 563, CV Mosby, St. Louis, 1978.23. Mann RA, Pfeffinger L. Hallux valgus repair: DuVries modified McBride procedure.

Clin Orthop 272:213–218, 1991.24. �Cih�ak R. Ontogenesis of the Skeleton and Intrinsic Muscles of the Human Hand and

Foot: Advances in Anatomy, Embryology, and Cell Biology, pp. 137–143, Springer-Verlag, Berlin, 1972.

25. Judge MS, LaPointe S, Yu GV, Shook JE, Taylor RP. The effect of hallux abductovalgus surgery on the sesamoid apparatus position. J Am Podiatr Med Assoc89:551–559, 1999.