DEFINITION

The term hallux rigidus refers to a painful condition of the first metatarsophalangeal (MTP) joint of the great toe that is characterized by restricted motion (mainly dorsiflexion) and periarticular bone formation.

The basic pathologic entity is that of degenerative arthritis.

Initially, hallux rigidus is characterized by pain, swelling, and MTP joint synovitis.

As the degenerative process proceeds, proliferation of bony osteophytes on the dorsal and dorsolateral aspect of the first metatarsal head develop.

With advanced disease, near-complete bony ankylosis may occur.

 

 

ANATOMY

 

The round, cartilage-covered first metatarsal head articulates with the somewhat smaller, concave base of the proximal phalanx.

 

Articulating on the plantar surface of the metatarsal head are the two sesamoids, which are contained in the tendon of the flexor hallucis brevis.

 

Distally, the two sesamoids are attached by the plantar plate to the base of the proximal phalanx.

 

The sesamoids are connected by the intersesamoidal ligament and protect, on their plantar surface, the tendon of the flexor hallucis longus within its tendon sheath.

 

Dorsally, the extensor hallucis longus is anchored medially and laterally by the dorsal capsule and MTP joint hood ligaments.

 

The tendons of the abductor and adductor hallucis pass medially and laterally but much closer to the plantar surface of the MTP joint (FIGS 1 and 2).

 

 

 

FIG 1 • Axial drawing of the first MTP joint.

 

PATHOGENESIS

 

The cause of hallux rigidus has not been determined, but joint trauma often is cited as a predisposing factor.

 

 

This may occur as a single episode, such as an intra-articular fracture, as a crush injury, or with repetitive microtrauma.

 

In a patient who sustains an acute injury to the MTP joint, forced hyperextension or plantarflexion may lead to an acute chondral or osteochondral injury.

 

The only documented factors associated with the cause of hallux rigidus are a flat or chevron-shaped metatarsal articular surface, bilaterality in those with a positive family history, and female gender.

 

Metatarsus primus elevatus typically is a secondary phenomenon related to the severity of the disease and restricted MTP joint motion and is not a primary cause of hallux rigidus (FIG 3).

 

NATURAL HISTORY

 

A patient with hallux rigidus typically complains of stiffness with ambulation and pain localized to the dorsal aspect of the first MTP joint that is aggravated by walking, especially during toe-off.

 

Patients tend to ambulate with an inverted foot posture to prevent stress on the first MTP joint.

 

With time and further osteophyte formation, increased bulk around the MTP joint periphery can lead to substantial discomfort with constricting footwear.

 

 

More than 80% of patients, if followed long enough, will develop bilateral symptoms. Ninety-five percent of patients with bilateral symptoms have a positive family history.

 

05

 

 

 

FIG 2 • Lateral drawing of the first MTP joint.

 

PATIENT HISTORY AND PHYSICAL FINDINGS

 

Interdigital neuroma

 

 

 

The interdigital spaces should be palpated for any tenderness. A Mulder test should also be performed.

 

The second and third interspaces are the most common locations for an interdigital neuroma.

 

Hammer toe or mallet toe

 

 

The patient should be examined while standing to evaluate for the presence of a hammer or mallet toe deformity.

 

Crossover toe

 

 

Inspection may reveal either medial or lateral deviation of the lesser toes. The MTP joints of the lesser toes should be palpated for plantar tenderness as well as thickening of the joint capsule. A drawer test of the lesser MTP joints also should be performed. Crossover toes usually affect the second and third digits.

 

Gastrocnemius contracture

 

 

A Silfverskiöld test should be performed to assess for a gastrocnemius contracture.

 

 

Table 1 Coughlin/Shurnas Clinical and Radiographic Classification of Hallux Rigidus

 

Grade

Dorsiflexion

Radiographa

Clinical

 

1. Forty to 60 degrees

   and/or 10%-20% loss compared with normal side.

   Normal or minimal findings No pain, only stiffness and loss of passive motion on examination

    

2. Thirty to 40 degrees

   and/or 20%-50% loss compared with normal side.

   Dorsal osteophyte is main finding; minimal joint space narrowing, minimal periarticular sclerosis, minimal flattening of metatarsal head

   Mild or occasional pain and stiffness, pain at extremes of dorsiflexion and/or plantar flexion on examination

    

3. Ten to 30 degrees

   and/or 50%-75% loss compared with normal side.

   Dorsal, lateral, and possible medial osteophytes giving flattened appearance to metatarsal head, no more than one-fourth of dorsal joint space involved on lateral radiograph, mild to moderate joint narrowing and sclerosis, sesamoids not usually involved but may be irregular in appearance

   Moderate to severe pain and stiffness that may be constant; pain occurs just before maximum dorsiflexion and maximum plantar flexion on examination

    

4. Less than or equal to 10 degrees and/or

   75%-100% loss compared with normal side. There is notable loss of MTP plantarflexion as well (often 10 degrees or less plantarflexion).

   As in grade 2 but with substantial narrowing, possible periarticular cystic changes, more than 25% dorsal joint may be involved on lateral side, sesamoids are enlarged and/or cystic and/or irregular.

   Nearly constant pain and substantial stiffness at extremes of range of motion but not at midrange.

    

5. Same as grade 3 Same as grade 3 Same as grade 3 but with definite pain at midrange of motion

aWeight-bearing anteroposterior and lateral radiographs are used. MTP, metatarsophalangeal joint.

From Coughlin MJ, Shurnas PS. Hallux rigidus. Grading and long-term results of operative treatment, J Bone Joint Surg Am 2003;85-A(11):2072-2088.

 

 

 

FIG 3 • Lateral radiograph of a patient with hallux rigidus and notable metatarsus primus elevatus (MPE). The

arrow shows the elevation of the first metatarsal relative to the second.

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

Weight-bearing radiographs (anteroposterior [AP], lateral, and sesamoid views) are obtained to evaluate the first MTP joint.

 

The Coughlin/Shurnas classification of hallux rigidus (Table 1) is used to grade the severity of joint arthrosis.

 

The AP radiograph often demonstrates nonuniform joint space narrowing with widening and flattening of the first metatarsal head.

 

An oblique radiograph may demonstrate a well-preserved joint space, which is obscured on the AP radiograph by overlying osteophytes.

 

On the lateral radiograph, with more severe disease, the dorsal metatarsal osteophyte resembles “dripping candle wax” as it courses proximally along the first metatarsal (FIG 4).

 

The lateral radiograph also may be used to evaluate for the presence of an elevated first metatarsal in relation to the lesser metatarsals. Up to 5 mm of elevation is considered normal (see FIG 3).

 

 

06

 

 

 

FIG 4 • Lateral radiograph of a patient with hallux rigidus. The arrow points to a large dorsal metatarsal osteophyte.

 

 

Dorsal proximal phalangeal osteophytes and loose bodies also may be seen.

 

Subchondral cysts and sclerosis in the first metatarsal head, widening of the base of the proximal phalanx, and hypertrophy of the sesamoids are characteristic findings in more advanced stages of hallux rigidus.

 

Rarely, a magnetic resonance imaging (MRI) scan may be necessary to identify an occult chondral or osteochondral injury in a younger patient with a history of an acute injury.

 

DIFFERENTIAL DIAGNOSIS

MTP joint synovitis

Osteochondral injury or loose body Gouty arthropathy

Hallux rigidus Rheumatoid arthritis

Turf toe or capsular ligamentous injury

 

 

NONOPERATIVE MANAGEMENT

 

Conservative management of symptomatic hallux rigidus depends on a patient's symptoms and the magnitude of the articular degenerative process (see Table 1).

 

Nonsteroidal anti-inflammatory drugs (NSAIDs) and a graphite insole or Morton extension to reduce MTP motion are the mainstays of conservative treatment (FIG 5).

 

Several commercially prefabricated orthoses provide rigidity to the forepart of the shoe and can be moved from shoe to shoe.

 

The addition of an extended steel or fiberglass shank placed between the inner and outer sole may be effective in reducing MTP joint motion as well.

 

Custom-made orthoses may be fabricated to reduce midfoot pronation, which also may help to reduce symptoms.

 

Table 2 Indications and Contraindications for Surgery

Indications

Contraindications

Grade 4 hallux rigidus

Active infection

Grade 3 hallux rigidus with less than

50% metatarsal articular cartilage remaining at the time of surgery

Significant interphalangeal (IP) joint degenerative arthritis

Deformity associated with severe

hallux valgus, recurrent hallux valgus, traumatic arthritis, and rheumatoid arthritis

Grades 1, 2, and 3 hallux rigidus (with >50% metatarsal

articular cartilage remaining at the time of surgery) in younger athletic patients, in which case a cheilectomy is

preferable.8,13,14

Neuromuscular disorder with

instability

Severe osteoporosis, which can make it difficult to stabilize a

fusion site with routine methods of internal fixation

Failed implant surgery of the first

MTP joint

 

 

 

 

FIG 5 • Graphite insole with liner used to restrict first MTP joint motion.

 

 

Unfortunately, orthoses also diminish available room in the toe box of the shoe, which may, in turn, increase pressure on the dorsal exostosis.

 

Occasionally, judicious use of an intra-articular corticosteroid injection may provide temporary relief of pain. Repeated injections, however, may accelerate the degenerative process and are discouraged.

 

Synovitis and limited MTP joint motion without radiographic changes should be evaluated by ruling out an inflammatory or erosive joint process with the following laboratory tests: serum complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), antinuclear antibody (ANA), rheumatoid factor (RF), human leukocyte antigen (HLA)-B27, and uric acid tests.

 

SURGICAL MANAGEMENT

 

Indications and contraindications for surgery are presented in Table 2.

 

 

07

Preoperative Planning

 

All imaging studies must be carefully evaluated.

 

An arthrodesis provides stability to the first MTP joint, maintains length of the first ray, relieves pain, achieves permanent correction of any deformity of the hallux, and allows the use of ordinary shoes.

 

For grade 4 hallux rigidus, salvage procedures in addition to MTP joint arthrodesis include excisional arthroplasty,6,14 soft tissue interpositional arthroplasty,7,14 and prosthetic replacement.14

 

The Keller procedure may be considered in more sedentary patients or the household ambulator with a grade

3 or 4 hallux rigidus. However, Coughlin and Mann6 reported significant postoperative metatarsalgia after excisional arthroplasty.

 

Positioning

 

The patient is placed supine on the operating table with a bump beneath the ipsilateral buttock to align the foot in a neutral position (FIG 6).

 

A popliteal, sciatic, or ankle block is used for anesthesia.

 

An Esmarch bandage is used to exsanguinate the foot and ankle. It is applied as an ankle tourniquet and wrapped just above the malleoli with a thin layer of padding beneath the bandage (FIG 7).

 

 

 

FIG 6 • Patient is positioned supine with a bump under the ipsilateral hip allowing the foot to rest in a neutral position.

 

 

 

FIG 7 • An Esmarch bandage is used as a tourniquet.

 

Approach

 

Numerous surgical techniques have been proposed describing various approaches, techniques of joint preparation, and methods of internal fixation to improve both the alignment and the success rate of arthrodesis.

 

Although the use of flat surfaces for MTP joint arthrodesis has been popular because of the simplicity of creating horizontal osteotomies of the proximal phalanx and metatarsal articular surfaces, this technique requires precision to obtain the desired alignment.

 

The joint is prepared with a power reaming system coupled with internal fixation with a dorsal plate, providing a strong construct that “brings the bones to the plate,” usually ensuring correct alignment.

 

The convex male reamer excavates the proximal phalanx to a concave congruous surface, whereas the concave female portion of the reamer shapes the metatarsal surface to a matching uniform, curved hemisphere (FIG 8).

 

The cup-shaped surfaces tend to resect less bone, reducing shortening of the first ray.

 

The curved nature of the cup-shaped surfaces allows preparation without predetermination of the dorsiflexion or plantarflexion, rotation, and varus and valgus alignment.

 

After the joint preparation is completed, the surgeon can then select the appropriate alignment for the MTP joint arthrodesis.

 

 

 

FIG 8 • Four sizes of matched metatarsal and phalangeal reamers.

 

 

08

TECHNIQUES

• Joint Exposure

A dorsal longitudinal incision is centered directly over the MTP joint in an interval between the medial and lateral common digital nerves.

The incision is extended from a point just proximal to the interphalangeal joint of the hallux to a point 3 to 4 cm proximal to the MTP joint.

The dissection is deepened along the medial aspect of the extensor hallucis longus tendon through the extensor hood and the joint capsule (TECH FIG 1A).

A thorough synovectomy is performed, and the MTP joint is inspected to locate osteophytes or loose bodies and to assess the extent of the articular cartilage damage (TECH FIG 1B).

 

 

 

 

TECH FIG 1 • A. Dissection is carried out medial to the extensor hallucis longus (EHL) tendon (arrow). B.

The EHL tendon has been retracted medially and a capsulotomy performed.

• Joint Resection and Decompression

   

  A thin section of the articular surfaces of the distal first metatarsal and proximal phalanx is removed using a sagittal saw (TECH FIG 2A,B).

   

  If further shortening of the first ray is desired, more bone may be resected from the metatarsal head.

   

   

   

  TECH FIG 2 • A. A wafer of the distal first metatarsal is removed. B. A thin section of the base of the proximal phalanx is resected. C. The medial eminence is resected in a patient with a hallux valgus deformity.

   

   

   

  By decompressing the MTP joint, increased exposure is achieved for the MTP joint surface preparation. A sagittal saw is also used to resect the medial eminence if the fusion is performed for a hallux valgus

  deformity (TECH FIG 2C).

• Metatarsal Head Preparation

   

  A 0.062-inch Kirschner wire (K-wire) is driven in a proximal direction at the center of the metatarsal head (TECH FIG 3A).

   

  The appropriate size of the reamer is chosen by comparing the diaphyseal width of the metatarsal to the inner size of the metatarsal reamer.

   

  The power reamer engages the K-wire and is then driven in a proximal direction, shaving the metatarsal subchondral surface and metaphysis to a cup-shaped convex surface (TECH FIG 3B).

   

  Any debris or excess bone along the periphery is removed with a rongeur.

   

  The K-wire is then removed and used to perforate the prepared metatarsal head in multiple places to increase the surface area for arthrodesis (TECH FIG 3C).

   

  09

   

   

   

  TECH FIG 3 • A. A K-wire is placed in the center of the metatarsal head. B. Power reamers prepare the metatarsal joint surface. C. Multiple perforations in the prepared metatarsal head.

• Proximal Phalangeal Preparation

   

  A 0.062-inch K-wire is centered on the base of the proximal phalanx and driven distally (TECH FIG 4A).

   

  The smallest of the convex cannulated phalangeal reamers is then chosen to prepare the phalangeal surface. Care must be taken to avoid “plunging” the reamer, as the proximal phalanx metaphyseal bone is often extremely osteoporotic beneath the subchondral bone.

   

   

   

  TECH FIG 4 • A. A K-wire is placed in the center of the base of the proximal phalanx. B. Power reamers prepare the proximal phalangeal joint surface. C. Multiple perforations in the prepared base of the proximal phalanx.

   

   

  Each successively larger reamer is used to enlarge the phalangeal surface until it matches the size of the prepared metatarsal surface (TECH FIG 4B).

   

  The K-wire is then removed and used to perforate the prepared phalangeal surface in multiple places to increase the surface area for arthrodesis (TECH FIG 4C).

   

  Cancellous bone shavings are collected throughout the joint preparation process and saved in a small cup to form a slurry for use as an autograft as the surfaces are coapted.

• Joint Alignment

   

  The bone slurry saved from the reamings is placed between the joint surfaces (TECH FIG 5).

   

  The congruous cancellous joint surfaces are coapted in the desired amount of varus and valgus, dorsiflexion and plantarflexion, and rotation.

   

  The desired position is 20 to 25 degrees of dorsiflexion, 10 to 15 degrees of valgus, and neutral rotation. For women who prefer high-heeled shoes, increased dorsiflexion at the fusion site may be desirable.

   

  All angular measurements relate to the axis of the first metatarsal shaft.

   

  An advantage of using the ball-in-socket surface preparation technique is that any dimension may be adjusted without disturbing the other alignment variables.

   

  10

   

   

   

  TECH FIG 5 • Cancellous autograft bone reamings are placed between the prepared joint surfaces before fixation.

• Internal Fixation

 

After obtaining proper alignment, the arthrodesis site is temporarily stabilized with one or two crossed 0.062-inch K-wires (TECH FIG 6).

 

A rongeur is used to smooth the dorsal aspect of the first metatarsal and proximal phalanx to allow the plate to sit flush against the bone.

 

The primary arthrodesis plate comes prebent to the desired dorsiflexion and valgus angles and is placed over the dorsal aspect of the prepared metatarsal and proximal phalanx (TECH FIG 7).

 

If more or less dorsiflexion is desired, the plate may be bent further to the desired dorsiflexion.

 

If more or less valgus is desired, the plate may be offset slightly to accommodate MTP joint angulation.

 

Bicortical self-tapping screws are used first to fix the plate to the proximal phalanx. Locking screws may be used in the presence of osteopenic bone, which is often the case.

 

The plate is then affixed to the metatarsal, with the first screw placed in compression. There is usually no need for locking screws in the metatarsal because the bone quality is generally better (TECH FIG 8A).

 

The K-wire is then removed, and a neutralization screw is placed to augment the fixation construct.

 

 

 

TECH FIG 6 • Temporary fixation with a 0.062-inch K-wire.

 

 

 

TECH FIG 7 • Precontoured primary arthrodesis plates.

 

 

The general philosophy is that in most cases, the plate can be trusted for appropriate alignment of the arthrodesis.

 

Using the flat surface of an instrument cover is helpful to ensure the hallux is in appropriate and acceptable dorsiflexion alignment.

 

The capsule and skin are then closed in a routine manner (TECH FIG 8B).

 

TECH FIG 8 • A. Dorsal plate in place. The compression screw will augment the fixation construct. B. Final wound closure with interrupted mattress sutures.

 

 

11

PEARLS AND PITFALLS
	Joint ▪ Results vary depending on the selected method of joint preparation. preparation ▪ An enlarged surface area is created by using the ball-and-socket-shaped reamers. Coupled with this, multiple perforations of the prepared surfaces and the use of a bony slurry aid in increasing the rate of successful joint fusion.   Alignment ▪ If the MTP joint is fixed in a straight position (minimal valgus or slight varus), the medial border of the hallux may impact the toe box of the shoe. Dorsiflexion of less than 10 degrees may cause a complaint of pressure at the tip of the toe. Malrotation in either pronation or supination is poorly tolerated (FIG 9). The use of precontoured plates helps to minimize this type of complication.   Internal ▪ A variety of methods can be used to stabilize the arthrodesis, including K-wires, fixation single or cross screws, staples, wire sutures, and plates. We have demonstrated a high rate of successful fusion with dorsal plates and a cross-compression screw.

 

 

 

	Radiographic ▪ Although preoperative radiographs may demonstrate an abnormally widened 1-2 parameters intermetatarsal angle, a first metatarsal osteotomy is rarely, if ever, indicated in combination with a first MTP joint arthrodesis. Typically, following decompression and arthrodesis of the first MTP joint, the 1-2 intermetatarsal angle will reduce substantially.
FIG 9 • Neutral rotation of the final arthrodesis. Note that the toenail is parallel to the plantar surface of the foot.

 

 

 

POSTOPERATIVE CARE

 

The foot is wrapped in a gauze-and-tape compression dressing following the surgery, and the dressing is changed weekly.

 

 

The patient is allowed to ambulate in a postoperative shoe or short walking boot. Weight initially is borne on the heel and lateral aspect of the foot.

 

Dressings are discontinued, and the patient is transitioned to normal shoe wear at 12 weeks after surgery with radiographic evidence of a successful MTP joint arthrodesis (FIG 10).

 

 

 

FIG 10 • A. AP and (B) lateral radiograph of a healed first MTP joint fusion.

 

 

OUTCOMES

In seven published series on the use of conical joint preparation and dorsal plate fixation for MTP joint arthrodesis, we have achieved a 95% fusion rate (313/327 first MTP joint arthrodeses).2,3,4,5,8,10,11,12

The preoperative diagnoses of this multiseries cohort included patients with hallux rigidus (28%); hallux valgus, as a primary, recurrent, or postoperative complication (41%); and rheumatoid arthritis (31%).

12

Of the 14 nonunions in this multiseries analysis, only 5 were symptomatic.

Although the concept of the ball-and-socket-shaped preparation of joint surfaces has changed little over the last two decades except for refinement of power reamer design,1,2,4,9,11,14 the techniques and design of the dorsal plate fixation have changed dramatically.

Our initial use of a stainless steel minifragment plate witnessed a 34% hardware removal rate (12/35) after fusion and occasional hardware failure.2

More recently, the use of a precontoured low-profile titanium plate has demonstrated a significant reduction in the incidence of hardware removal to 2% (2/99 cases).10,11

Subjective good and excellent results were noted in 92% of cases (301/327 feet).

Overall, 48 patients were noted to have slight progression of interphalangeal joint arthritis, but only 6 were symptomatic.

 

COMPLICATIONS

Nonunion Malunion Hardware failure

 

Interphalangeal joint arthritis

 

 

REFERENCES

1. Coughlin MJ. Arthrodesis of the first metatarsophalangeal joint. Orthopaedic Review 1990;19:177-186.

    

    

2. Coughlin MJ. Arthrodesis of the first metatarsophalangeal joint with mini-fragment plate fixation. Orthopaedics 1990;13:1037-1048.

    

    

3. Coughlin MJ. Rheumatoid forefoot reconstruction. A long-term follow-up study. J Bone Joint Surg Am 2000;82(3):322-341.

    

    

4. Coughlin MJ, Abdo RV. Arthrodesis of the first metatarsophalangeal joint with Vitallium plate fixation. Foot Ankle 1994;15:18-28.

    

    

5. Coughlin MJ, Grebing BR, Jones CP. Arthrodesis of the metatarsophalangeal joint for idiopathic hallux valgus: intermediate results. Foot Ankle Int 2005;26:783-792.

    

    

6. Coughlin MJ, Mann RA. Arthrodesis of the first metatarsophalangeal joint as salvage for the failed Keller procedure. J Bone Joint Surg Am 1987;69(1):68-75.

    

    

7. Coughlin MJ, Shurnas PJ. Soft-tissue arthroplasty for hallux rigidus. Foot Ankle Int 2003;24:661-672.

    

    

8. Coughlin MJ, Shurnas PS. Hallux rigidus. Grading and long-term results of operative treatment. J Bone Joint Surg Am 2003;85-A(11): 2072-2088.

    

    

9. Coughlin MJ, Shurnas PS. Hallux rigidus. Surgical techniques (cheilectomy and arthrodesis). J Bone Joint Surg Am 2004;86A(suppl 2): 119-130.

    

    

10. Doty J, Coughlin MJ, Hirose CB, et al. Hallux metatarsophalangeal joint arthrodesis with a hybrid locking plate and a plantar neutralization screw: a prospective study. Foot Ankle Int 2013;34(11): 1535-1540.

     

     

11. Goucher N, Coughlin M. Hallux metatarsophalangeal joint arthrodesis using dome-shaped reamers and dorsal plate fixation: a prospective study. Foot Ankle Int 2006;27:869-876.

     

     

12. Grimes JS, Coughlin MJ. First metatarsophalangeal joint arthrodesis as a treatment for failed hallux valgus surgery. Foot Ankle Int 2006;27:887-893.

     

     

13. Mann RA, Coughlin MJ, DuVries HL. Hallux rigidus: a review of the literature and a method of treatment. Clin Orthop Relat Res 1979; (142):57-64.

     

     

14. Shurnas P, Coughlin M. Arthritic conditions of the foot. In: Coughlin M, Mann R, Saltzman C, eds. Surgery of the Foot and Ankle, ed 8. Philadelphia: Elsevier, 2007:805-922.