CHAPTER

THE YOUNG'S TENOSUSPENSIONDonald R. Green, D.PM../obn Colson, DPM.

The Young's tenosuspension entails rerouting all orone-half of the tibialis anterior tendon through aslot fashioned in the navicular. The tendon is notdetached from its insefiion at the medial-plantaraspect of the medial cuneiform-first metatarsalbase. Rather, it is slipped into the navicular key-hole slot by supinating the foot and stretching thetendon plantarly and posteriorly. The resultingposition will create a new insefiion for the tibialisanterior tendon into the dorsum of the navicular.The remainder of the tendon will function like aligament to support the medial arch (Fig. 1).

Figure 1. The Young's suspension rerolrtes the tibialis anterior througha keyhole slot in the navicular,

This will accomplish four functions: 1. Thetibialis anterior will continue to be capable ofinvefiing the foot around the longitudinal axis ofthe midtarsal joint (Fig. 2A). 2. The tibialis anteriorwill continue to function as one of the primarydorsiflexors of the foot at the ankle joint. (Theextensor halluces longus and the extensor digito-rum longus are the other two primary dorsiflexorsof the foot at the ankle jointXFig. 2B). 3 The distalportion of the tendon will become a strong liga-ment in the medial arch, running from the plantaraspect of the first metatarsal to the plantar aspect ofthe navicular (Fig. 2C). 4. Finally, the procedureremoves the dorsiflexory force of the tibialis

Figure 24. The tibialis anterior has a supinatory(inverting) force around the longitudinal axis ofthe midtarsal joinr.

anterior around the first ray axis (Fig. 2D). Thisallows a mechanical advantage to the plantar-flexory force of the peroneus longus (Fig. 2E). Mostof the time, this loss of dorsiflexory power of the 1stray during swing phase of gait does not lead to acocked hallux, although this is theoretically possible.

In the eady seventies, this procedure wasused alone or in combination with a tendo-achilleslengthening for corection of flexible pes valgoplanus foot deformities with good to satisfactoryresults. More commonly today, the Young'ssuspension is utilized with the Kidner tibialisposterior advancement as part of the medial archreconstruction, with more effective results (Fig. 3).However, there are times when the Young's sus-pension is still utilized as an isolated procedure.

I4 CHAPTER 1

Figure 2C. The distal portion of the tibialis antedor tendon *'illbecome a ligament for the medial arch. The ligament extends from thebase of the 1st metatarsal-1st cuneiform level to the navicular.

Figure 28. The tibialis anterior has a dorsiflexory force across the ankle joint.

Figure 2D, The tibialis anterior has a dorsiflex-ory forre arotrnd the lsl ray axi5.

Figure 28. The peroneus longus functions toplantarflex the 1st ray. It also resists dorsiflexionof the 1st ray.

CHAPTER 1

Figr"rre J. The medial arch reconstruction includes a combination ofthe Young's suspension and the meclial advancement of the tibialisposterior (Kidner procedure).

CASE REPORT

JJ. is an 17-year old black maie who had difficultywalking and frequently crawled. He had a dorsalprominence of his first metatarsal head and pain inthe area. He was mentally abused by his father, andhad a low self-esteem (Fig. 4A, 4B).

The patient's mother reported that her sonhad a history of a clubfoot as a young child. Earlysurgical correction was attempted, bilaterally. It isdifficult to know what procedure was done to cor-rect the clubfoot as an infant, as no records wereavailable. There is a residual medial scar at therearfoot and ankle area.

Examination revealed adequate range-of-motion of the subtalar, midtarsal, and ankle joints.There was limited eversion of the subtalar jointbeyond perpendicular. The forefoot was invertedrelative to the rearfoot in a neutral position, butflexible. There was a limited range of dorsiflexionat the first metatarsophalangeal ioint, but 90degrees of plantarflexion was available.

Although the peroneus longus appeared to bestrong, the function of the foot resembled thatwhich would be expected if the peroneus longuswas weak. The patient walked with an interestinggait, with the foot in a supinated position contact-ing the ground with the lateral aspect of the foot,and with the hallux plantarflexed.

Radiographs demonstrated dorsal subluxationof the navicular on the talus. The foot was maxi-ma1ly pronated with occlusion of the sinus tarsi bythe leading wall of the posterior facet of the talus(positive Kirby's sign). There was a low calcaneal

Figure 4A. AlthoLrgh the left foot is pronated, the forefoot is in asLlpinatlls attitude. The hallux is plantarflexecl and the 1st ray is inelevatus. There is a dorsal prominence of the 1st metatarsal head.

Figure 48. Lateral view.

inclination angle, with little superimposition of thelesser tarsals and the metatarsal bases on the lateralview. The hallux was plantarflexed with an obviousmetatarsus primus elevatus (Fig. 5A).

A low talocalcaneal angle (Kite's angle) wasnoted on the dorsoplantar view. The cuboid abduc-tion angle was increased. A normal metatarsusadductus angle with a low forefoot adductus anglealso signified a pronated foot (Fig. 5B).

Figure 5A. The lateral x-ray:-

Dorsal subluxation of the navicular on the talus.-

Occlusion of the sinus tarsi by the leading rvall of the talus(positive Kirby's sign) demonstrates pronation.

-

A lol,, calcaneal inclination angle is seen.-

Little superimposition of the lesser tarslls is noted,-The hallur is plantarflexed.-

Metatarslls primus elevatus is obviotts.

CHAPTF]R 1

Figure 5R. The DP x-ray:-

A low talocalcaneal angle (Kite's angle) is present.-

The cuboicl abcluction angle is high.-

A low forefoot adductus angle in combination nith a norn'ralmetatarsus adcluctus angle signilies a pronated foot.

The authors' initial impressions includedhallux limitus, a significantly plantar-flexed halluxand metatarsus primus elevatus, and forefootsupinatus with a pronated foot. Consen/ative ther-apy afid orthotics failed to reduce the symptomsand, therefore, surgical correction was considered.The specific surgical options included arthrodesisof the metatarsophalangeal joint, plantarflexoryosteotomy of the first metatarsal, triple arthrodesis,and tendon transfers.

Although some limitation of eversion was pre-sent in the rearfoot, a Young's tenosuspension wasrecommended. There was a forefoot supinatus withmetatarsus primus elevatus. The hallux was plan-tarflexed with limited range of motion of the firstmetatarsophalangeal joint. The tibialis anterior andperoneus longus tendons were both strong.

The Young's tenosuspension intends todecrease the force on the forefbot supinatus and themetatarsus primus elevatus. This will decrease theplantarflexory force on the hallux. The dorsiflexoryforce of the tibialis anterior at the ankle should bemaintained, giving an advantage to the peroneuslongus, and dynamically providing a force to reducethe supinatus and plantarflex the first ray.Gradually, this will allow increased range of dorsi-flexion of the first metatarsophalangeal joint.

The ProcedureA dorsomedial curved incision is made from thebase of the 1st metatarsal over the dorsai medialaspect of the medial cuneiform and navicular, andends inferior to the medial malleolus (Fig. 6A). The

incision is carried deep in anatomic layers. Theextensor retinaculum and deep fascia are incised,identifying the tibialis anterior tendon (Fig. 5B). Ahorizontal incision is made through the periosteumover the medial cuneiform and navicular bones.The periosteum is reflected plantarly to allow forrouting of the tendon under these bones. A vertical"T" periosteal incision is made over the dorsome-dial aspect of the navicular to provide exposure fora drill hole in the navicular. The hole is made fromdorsal-proximal to plantar-distal (Fig. 5C). A siot isdeveloped from the drill hole, medially and proxi-mally (Fig. 5O). fne plantar surface of the mediaicuneiform and navicular is adequately exposed toallow for seating of the tibialis anterior tendon (Fig.6n). Using two surgical drains or two moist umbil-ical tape sections, the tendon is pulled proximallyand plantarly while the foot is held in full supina-tion (Fig. 6F). A distal force applied to the proximalaspect of the tendon will facilitate seating of thetendon into the slot in the navicular (Fig. 6G). \7iththe tendon locked in place, the periosteum isclosed, reinforcing the tendon's new insertion intothe dorsal navicular (Fig. 6H). The wound is thenclosed in anatomic layers, and the foot is dressedand casted in a mildly supinated position. A short-leg walking cast is kept in place for 4-6 weeks.

Figure 6A. The incision is macle on the dorsalmedial aspect of the foot, starting from the baseof the lst metatarsal and extending to a positk)ninferior to the medial malleolus.

CHAPTER 1

Figure 68. The tibialis anterior is identifiedundel the deep fascia and extensor retinacuh,rm.

Figure 6D. A slot is clirected fron-r the drill holemedially end posteriorly in the navicul:rr.

Figure 6C. A drill hole is made in the navicr:iarfrom dorsal-proximal to plantar-dista1.

Figure 6E. Adequate periosteal reflection plantarlyis neccssary to alkrrl,- tl-re tibialis anterior tendon toseat under tl're cuneifbrm ancl the navicular.

CHAPTER 1

Figure 6F. The tibialis anterior is pu1led posterl-orly ancl inf'eriorly s,ith the fbot in supination,using two rublLrer drains.

Figure 6H. \fith the tendon locked in place, theperiostellm can be closed around it, reinforcingthe tendon at the dorsal ntvicul:rr area.

Figure 6G. Distal force applied to the prorimalaspect of the tenclon will snap the tenclon intothe slot of the navicular.

Although the Young's procedure is usually justa pafi of the medial arch reconstruction, in thispatient, it was used as an isolated procedure. TheYoung's suspension tendon-balancing techniquegives mechanical advantage to the peroneus longustendon. This allows dynamic improvement of footfunction to continue, even after the surgery hashealed. Fufihermore, it decreases the forefoot func-tion of the tibialis anterior, while still allowing thenormal ankle joint function of dorsiflexion. In thispatient, the forefoot supinatus was reduced, therewas an increased range of motion of the firstmetatarsophalangeal joint. The young man is nowable to run and play, and is no longer crawlinpa toget around (Figs. 7A, 7B).

CHAPTER 1

Figure 7A. Thirteen months postoperatively the forefoot supinatus hasbeen reducecl. The plantarflerecl hallux ancl the metatarslrs primllseler.atus have been reducecl. The foot is less pronated.

At 13 months postoperative, radiographs con-tinuecl to demonstrate some subluxation of thenavicular on the talus. There is no longer lneximumpronation. Occlusion of the sinus tarsi by the lead-ing wali of the posterior facet of the talus is nolonger seen. The calcanezri inclination angleremains low, how'ever superimposition of thelesser tarsus and the metatarsal bases on the lateralview is markedly increased from the preoperativefilms. The hallux is more parallel to the grolrnd,and the metatarsus primus elevatus is markedlyreduced (Fig. BA).

Figure 78. Thirteen months postoperatir"e.

The talocalcaneal angle (Kite's angle) remains1ow on the dorsoplantar view-. Although the cuboidabduction angle remains increased, the forefootadductus angle has also increased. This alsodemonstrates less pronation postoperatively in thefoot (Fig. BB).

Although the criteria for r-rtilization of theYoung's suspension as an isolated procedure isvery narrow, it can still be an effective procedure.The key to appropriate utllization is a thoroughunderstanding of the biomechanics of foot func-tion, and a specific appreciation of the function ofthe tibialis anterior tendon.

Figure 8A. Lateral x-r-ay 13 months postoperatively:-

The calcaneal inclination angle remains 1or,.-

Increasecl sllperimposition of the lesser tarsus and n'ret:rtarsal b:rseis noted.The hallux is more par:rllel to the gr-ound.

- NletatarsLls primr.rs eler.atus is significantly reducecl.

Figure 8B. Dorsel plantar x-r'ay 13 months postoperativelY:-

The talocalcancal angle (Kite's angle) remains lon'.-

The cuboid abduction angle remains increased.-

The forefbot aclductr:s ;rng1e is increased fiom preoperative valuesdcmonstrating rechrced pronation.