CHAPTER 21 TRANSVERSE PIANE METATARSOPHAIANGE,AL DEFORMITY Another Etiology and Solution

Stepben J. Miller, D.P.M.

The second metatarsophalangeal joint (MPJ) is a Both the pain and the degree of transverse location of frequent pathology in the , often plane deformity are usually insidious in onset, and resulting in metatarsalgia-type pain. It may be the toe most often adducts towards the hallux, associated with such deformities as plantar plate although it may present abducted. The second MPJ subluxation, a second metatarsal that is relatively is the most commonly affected joint. Without too high or too low, too short or too long, or flexor correction, the transmetatarsophalangeal joint tendon malalignment. The joint itself may present tendons tend to displace, and the capsule contracts with nontraumatic synovitis, predislocation ipsilateral to the direction of the deformity. Over syndrome, degenerative joint disease, rheumatoid time, the head of the metatarsal will adapt to the arthritis, or avascular collapse due to Freiberg's same direction, resulting in "tracking" of the toe in infraction. its altered position. In addition, the plantar plate There may also be associated sagittal, frontal, will tend to shift in the same direction, carrying or transverse plane deformities of the second toe with it the flexor tendons. Once this shift takes which may present singularly or in any combina- place, the transverse plane deformity increases as tion. Probably the most difficult component to treat the change in vector force gives the contracting successfully is the transverse plane deformity tendons more mechanical advantage. Thus, a occurring at the MPJ (Fig. 1). Although this may or vicious cycle ensues. may not be symptomatic, it is usually pain that In its early stages, the deformity is simply a brings the patient into the clinical setting. subluxation at the MPJ (Fig. 2). Howeveq over time

Figure 1. Clinical appearance of a second toe Figure 2. Transverse plane deformity at the transverse plane deformity. second MPJ. CHAPTER 21 125

there often develops flexion contractures at the Over time, the medial second MPJ structures interphalangeal of the toe. Occasionally, the contract and the thicker laletal joint structures toe may even rotate in the frontai plane at the same stretch, making the digital deformity less reducible. time. In its most extreme degree, the second toe As the planlar plate shifts medially, it carries with it will overlap the hallux. the flexor tendons which are firmly held within the sheathed plantar groove of the plate.'z Once the ETIOLOGY flexor tendons have moved medial to the vertical axis of the second MPJ, their force vector pulls Determining what initiates this transverse plane the second toe into further adduction, thereby deformity remains an enigma. There is very little increasing the deformity. \fith such imbalance, the information in the medical literature to date that medial interosseous tendon attached to the base of addresses this entity alone. Various descriptive the proximal phalanx will add its force to the terms really address a continuum of instability adduction as it gains mechanical advantage. leading to subluxation of the (usually second) A congenital shofi first metatarsal may also metatarsophalangeal joint that occasionally lead to transverse plane deformity of the second eventuates in complete dislocation (Table 1). The toe, but it will generally take a much longer time transverse plane deformity is a frequent component for the functional pull of the DTIL to overwhelm of this syndrome. the stabilizing structures about the second MPJ plantar p1ate.

Table 1 SURGICAL CORRECTION TERMS TO DESCRIBE Conservative measures to straighten the toe rarely SECOND MPJ PROBLEMS give permanent correction. Pain about the joint can be relieved with steroid injection,3 toe taping or Predislocation Syndrome of the Lessor MPJ splinting,a and shoe or orthotic modifications. The Melatarsal/Neuroma Sub-2nd Syndrome pain relief is usually only temporary as the actual Chronic Lesser Metatarsalphalangeal Dislocation deformity will progressively worsen. Floating Toe Syndrome Lesser MPJ Instability Syndrome Second MPJ Dislocation/Subluxation Nontraumatic Synovitis of the Second MPJ Crossover Second Toe Deformity Second Metatarsophalangeal Joint Instability

Based on clinical obselations, including response to treatment, one probable etiology relates to the deep transverse intermetatarsal (DTIL) befween the first and second metatarsophalangeal joints (Fig. 3). According to Sarrafian' and Deland et a1.,2 the plantar plate of the second MPJ is attached transversely to the sesamoid apparatus of the first MPJ via the DTIL. The plantar plate is firmly connected to the proximal phalanx of the toe. Therefore, if there is any increase in tension on the DTIL, as for example when the first metatarsal is shortened iatrogenically in hallux valgus surgery, the DTIL will pull the plantar plate and proximal phalanx Figure 3. Deep transverse intermetatarsal ligament connecting the plantar plate of the toward the hallux, instigating a transverse plane second metatarsophalangeal joint to the digital deformity. sesamoid apparatus underneath the first metatarsophalangeal joint. 126 CHAPTER 21

Surgical procedures for correcting transverse flrated with screws (Fig. 5), whereas a cylindrical plane second toe deformities at the MPJ have shortening osteotomy can be fixated with a plate included arthroplasties,a,5 various tendon transfers,6-e (Fig. 6), or a screw if it is angulated. Once the coliateral ligament reconstruction,'o " and a second metatarsal is shortened, the second toe will metatarsal head osteotomy.5 The osteotomy can be spontaneously fall back into coffect alignment either transpositional to realign the metatarsal head (Figs. 7A, 78, BA, BB). back over the plantar plate (Fig. 4) or angulational The greatest advantage here is that the to reduce the medially directed articular adaptation. metatarsophalangeal joint does not have to be violated and no digital pinning is required. A NEW APPROACH disadvantage is the postoperative care necessary to heal the osteotomy. Unfortunately, this procedure Since a short first metatarsal leaves a relatively long is not helpful in the long term deformities where second metatarsal, then one method of reducing there are advanced contractures of the soft tissues the deforming tension on the DTIL is to shofien and adaptations of articular structures. It is offered the second metatarsal. This can be done via a as an additional technique to address the difficult diaphyseal osteotomy using a technique of choice. transverse plane digital deformity. It also offers For example, a shortening Z-osteotomy can be some insight into the etiology of the problem.

Figure 5. Shortening Z-osteotomy of the second metatarsal resulting in realignment of the second MPJ.

Figure 4. Transpositional osteotomy of a metatarsal head to relocate a dislocated second MP ioint by repositioning the head over the plantar plate.

Figure 6. Cylindrical shortening; osteotomy of the 2nd metatarsal resulting in relocation of the 2nd MPJ. CHAPTER 21 127

Figure 7A. Cxse +1. Preoperative x-ray of Figure 78. Case +1. Relocation of the 2nd X{PJ sr,rbluxing second MPJ. alter shortening osteotomy of the 2nd metatarsal.

Figure 8A. Case #2. Preoperative x-r'ay of sublux- f-igr-rre 8B. Case #2. Relocation of the second NIPJ ation transverse plane cleformitl, of the second by shortening of the second metatarsal. toe. 128 CHAPTER 21

REFERENCES ADDITIONAL REFERENCES

Sarrafian SK: Anatomy of tbe Fctot arul : Descriptiue, Coughlin MJ: Crossover second toe defbrmity. Foot Ankle 8:29-39, Topograpbical, Functional 2nd ed. Philadelphia, Pa: Lippincott: 7987. 7993: 207-217. Coughlin MJ:Subluxation and clislocation of the second metatarsalpha- Deland JT, Lee KT, Sobel M, DiCarlo EF: Anatomy of the plantar langeal joint. Oftbop Clin Nor.th Am 20:i39-55I, 1989. plate and its attachments in the lessor metatarsal phalangeal joint. Coughlin MJ: Second metatarsalphalangeal joint instability in the Foctt Ankle Int 161480-486, 1.995. athlete. Foot Ankle 74:309-379, 1993. Mizel MS, Michelson JD: Nonsurgical treatment of monarticular dePalma L, Gigante A, Ventura A, Chillemi C: Regnauld procedure in syno\.it1s of the second metatarsophalangeal joint. Foot Ankle Int the surgical treatment of metatarsalgia: Interpretation of fo11ow- L8:421-426, 7997. up x-ray imaging. J Foot Ankle Surg 36:1,65-169, 7997. 1. Yu GV, Judge M: Predislocation syndrome of the lesser metatarsal Harris RI, Beath T: The shot first metatarsal; Incidents and clinical phalangeal joint: a clistinct clinical entity. In Camasta CA, Vickers significance. rlBone Joint Surg 41A:553-565, 1919. NS, Carter SR eds. Reconsh.Ltctioe Surgery of tbe Foot and leg, Johnston RB, Smith J, Daniels T: The plantar plate of the lessor toes: Update 95 Tucker, Ga; The Podiatry Insrirure Publishing; 1!!!r an anatomical study in human cadavers. Foot Ankle 751276- 282, 709-773. r994. Phillips AJ: Chromc lesser metatarsal phalangeal dislocations, In Maxw-ell JR, Carro, A, Bean G, Carpenter B; Evaluation of the Camasta CA, Vickers NS, Ruch JA, eds. Reconstructiue Swgery of sub-second metatarsal/neurorna synclrome. In:Camasta CA, lhe F'oot and leg, Update 94, Tucker, Ga; The Podiatry Institute Vickers NS, Rr-rch JA, eds. Reconstrucliue Surgety ctf tbe Foot and Ptrblishing; 1,994:81,-90. Leg, Update p4 Tucker, Ga; The Podiatry Institute Publishing; Thompson FM, Hamilton \[G: Flexor tendon transf'er for 1994$9-74. metatarsal phalangeal instability of the second toe. Foot Ankle Morton DJ: Tbe Human Foot: It's Euolution, Pbysiology, and 14;385-388. 1993. Functional Disoldens. Ne$,- York;Hafher Publishing;1935: 1963. Schuberth JM, Jensen R: Flexor digitar longus transfer for second metatarsal-phalangeal joint dislocation/subluxation. In Vickers NS, et al. Reconstructioe Suryery of the Foot and. Leg, Llpddte 97, Tucker, Ga; The Podiatry Institute Publishing; Tucker, Ga: 1997: 17-74. 8. Rucl'r JA; Use of the EDB tendon for muscle-tendon balance of the lessor MPJ. In Camasta CA, Vickers NS, Cafter SR eds. Reconst?uctit)e Surgery of the Foot.tild Leg, tpdare 95Tucker, Ga; The Podiatry Instltute Publishing; 7995 :111-LL8. 9. Schwartz N: Ner,v procedure for stabilization of lessor metatarsal- phalangeal joints: A preliminary study. / Foot Ankle Surg 36:236-239, 1997 . t0 Ruch JA: A surgical technique for repair of the "pre-dislocation syndrome". Tn Camasta CA, Vickers NS, Carter SR eds. Reconsh ctiL)e Surgery of tbe Foot and Leg, t.lpdate 95Tucker, G^; The Pocliatry Institute Publishing; 1995 :7 -70. 11 Deland JT, Sobel M, Amoczky SP, Thompson FM: Collateral Ligament Reconstruction of the unstable metatarsalphalangeal joint: an in vitro study. Foot Ankle 13:391-395, 1992.