DEFINITION

Hallux rigidus, osteoarthrosis of the first metatarsophalangeal (MTP) joint, was first described by Cotterill8 and Davies-Colley12 in 1887.

Pain and restriction in range of motion (ROM) in the first MTP joint are the major characteristics of hallux rigidus.41

After hallux valgus, hallux rigidus is the second most common deformity of the first MTP joint. The big toe is the location in the foot with the highest incidence of osteoarthrosis; estimates suggest that nearly 10% of the adult population is affected by hallux rigidus.18,19

The incidence of hallux rigidus is higher in women than in men.5,6

 

 

ANATOMY

 

The first MTP joint is a stable joint formed by the rounded head of the first metatarsal bone fitting into the concave proximal facet of the proximal phalanx.

 

The joint is enhanced by the plantar and collateral ligaments. The deep transverse metatarsal ligament is connected to the second ray.

 

The sesamoid bones are embedded in the flexor hallucis brevis tendon. They are accommodated at the underside of the first metatarsal in two longitudinally oriented grooves. In a normal relationship, the sesamoids glide distally and proximally within the grooves by a combination of active and passive forces.

 

The extensor hallucis longus tendon covers the dorsal side of the first MTP joint and inserts into the base of the distal phalanx.

 

The dorsomedial cutaneous nerve is in danger when using a dorsomedial approach to the joint. It is the most medial branch of the superficial peroneal nerve. An anatomic study has shown that the minimum distance from

the medial edge of the extensor hallucis longus tendon is 6 mm.36

 

PATHOGENESIS

 

The mechanism responsible for developing hallux rigidus remains unclear.

 

In theory, damage to the cartilage surface of the first MTP joint, that is, osteochondral fractures or chondral defects, may lead gradually to posttraumatic arthrosis.

 

Alternatively, repetitive microtrauma to the first MTP joint, with eccentric overload and stresses that exceed physiologic stresses, may result in hallux rigidus, as seen in football players and ballet dancers.

 

The contact distribution shifts dorsally with increasing degrees of extension.1 This is consistent with the

observation that chondral erosions often initially affect the dorsal aspect of the articular surface of the first metatarsal.

 

Various factors, in isolation or in combination, have been suggested as contributing to the development of first MTP joint arthrosis: (1) hyperextension injury (ie, turf toe injury) to the hallux, (2) metatarsus primus elevatus,

(3) osteochondral lesions, (4) a long first metatarsal, or even (5) wearing inappropriate shoes.6,23,27,29,32,40,41

 

In 2003, Coughlin and Shurnas9 evaluated 114 patients treated operatively for hallux rigidus over a 19-year period in a single surgeon's practice for demographics, etiology, and radiographic findings associated with hallux rigidus.

 

 

The disease was not associated with metatarsus primus elevatus, first ray hypermobility, increased first metatarsal length, Achilles or gastrocnemius tendon tightness, abnormal foot posture, symptomatic hallux valgus, adolescent onset, footwear, or occupation.

 

Hallux rigidus was associated with hallux valgus interphalangeus, female gender, and a positive family history in bilateral cases.

 

In most cases, the problem was bilateral, except when trauma was involved—if trauma had occurred, then the problem was unilateral.

 

Metatarsus adductus was more common in patients with hallux rigidus than in the general population, but no significant correlation was found.

 

A flat or chevron-shaped MTP joint was more common in patients with hallux rigidus.

 

NATURAL HISTORY

 

The natural history of hallux rigidus is similar to that of degenerative arthritis in any joint. Once the process has started, the articular cartilage is more susceptible to injury, resulting from shear and compressive forces. The subchondral bone shares these stresses, which subsequently lead to increased subchondral bone density and formation of periarticular osteophytes. The osteophytes limit first MTP joint motion and further compromise the normal mechanics of this joint. This effect can accelerate the degenerative process.

 

The natural history is, at the end point, stiffness and constant pain. The length of time that elapses from initial symptoms to constant pain varies widely. The standard time frame over which daily or recreational sports activities become painful is about 5 to 10 years, whereas athletes (eg, tennis and basketball players) who experience constant and repetitive impacts develop constant symptoms in a shorter period of time. In most patients, stiffness is not an issue.

 

Outcomes in 22 patients with hallux rigidus representing 24 feet treated nonoperatively at an average followup of 14.4 years showed that the pain remained about the same in 22 feet, improved with time in 1 foot, and became worse in

 

50

1 foot. There was measurable loss of cartilage space radiographically over time in 16 of 24 feet, and in 8 of the 16 feet, the loss of cartilage space was dramatic.16

PATIENT HISTORY AND PHYSICAL FINDINGS

 

Hallux rigidus is associated with a positive family history of great toe problems in almost two-thirds of patients.9

 

The standard history is a trauma at the MTP joint several years earlier, but more often, we find active persons

—mostly former athletes—who are performing high-impact sports such as tennis, golf, or basketball. Starting with “feeling the joint” after exercising, it becomes a progressively limiting factor that prevents them from performing their sport at their normal level.

 

The true etiology of hallux rigidus is often not known.

 

In the early stages, the patient complains of pain only on dorsiflexion of the great toe; the ROM is unaffected or only moderately restricted. In the midstage of hallux rigidus, the patient complains of motion-dependent pain. Dorsiflexion of the great toe is restricted. Osteophytes may occur dorsal to the first metatarsal head and may be palpable, the plantar structures become tight, plantarflexion becomes painful at the sesamoid-metatarsal joint (mostly medial), and the ROM also is restricted. A dynamic stress test in dorsiflexion (ie, pressure with the thumb on the medial or lateral sesamoid) can distinguish between sesamoid-metatarsal head pain and MTP pain. Unfortunately, this test is not clear in the presence of ongoing stiffness and arthritic changes of the MTP joint. The late stages present with reduced to complete inhibited dorsiflexion and plantarflexion of the toe, with palpable osteophytes dorsal (medial and lateral) to the metatarsal head and especially around the entire phalangeal base.

 

The most striking physical manifestation of hallux rigidus noticed by patients is the bony prominence at the dorsum of the metatarsal head, which is disturbing and painful, especially in firm leather shoes.

 

Methods for examining the first MTP joint are as follows:

 

 

ROM, dorsiflexion, and plantarflexion are checked. In the early stages, restriction of dorsiflexion (“dorsal impingement”) is found. In later stages, restriction of plantarflexion and pain at the midrange of the motion arc (indicative of global first MTP joint degenerative joint disease) also are found.

 

 

 

 

FIG 1 • A. Hallux rigidus grade 2 on AP weight-bearing radiograph. B. Hallux rigidus grade 3 on AP weight-bearing radiograph. C. MRI scan showing an osteochondral lesion of the metatarsal head.

 

 

Palpation of the first MTP joint. In later stages, palpable and painful osteophytes are present as a symptom of ongoing osteoarthritis.

 

Inspection for clinical changes in form or color of the first MTP joint

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

Standard weight-bearing anteroposterior (AP) (FIG 1A,B) and lateral radiographs of the foot as well as weight-bearing radiographs of the metatarsals and, in cases of sesamoid pathologies, a sesamoid special radiograph should be performed.

 

Coughlin and Shurnas10 proposed a classification system based on the radiographic system of Hattrup and

Johnson20 that is representative of the natural history. It includes ROM, as well as radiographic and examination findings, as follows:

 

 

Grade 0: dorsiflexion of 40 to 60 degrees (ie, 20% loss of normal motion), normal radiographic results, and no pain

 

Grade 1: dorsiflexion of 30 to 40 degrees, dorsal osteophytes, and minimal to no other joint changes

 

Grade 2: dorsiflexion of 10 to 30 degrees; mild flattening of the MTP joint; mild to moderate joint narrowing or sclerosis; and dorsal, lateral, or medial osteophytes

 

Grade 3: dorsiflexion of less than 10 degrees, often less than 10 degrees plantarflexion, severe radiographic changes with hypertrophied cysts or erosions or with irregular sesamoids, constant moderate to severe pain, and pain at the extremes of the ROM

 

Grade 4: stiff joint, radiographs showing loose bodies or osteochondritis dissecans, and pain throughout the entire ROM

 

Indications for magnetic resonance imaging (MRI) in MTP-sesamoid pathology include the following:

 

 

 

Severe pain in the MTP complex unrelated to radiographic results Absence of visible joint space narrowing on radiography

 

 

Suspected osteochondral lesion in the metatarsal head on radiography Suspected sesamoid arthritis or necrosis on radiography

 

51

 

The MRI examination should include sagittal, axial, and coronal views with T1-weighted (TR 35 ms, TE 16 ms) and high-resolution gradient echo (TR 1060 ms, TE 16 ms) images (FIG 1C).

 

DIFFERENTIAL DIAGNOSIS

Gout

Rheumatoid arthritis Psoriatic arthritis Reiter syndrome Infectious arthritis

Sesamoid osteonecrosis

 

 

NONOPERATIVE MANAGEMENT

 

The primary nonoperative treatments of hallux rigidus are anti-inflammatory therapy and pain relief by orthotic devices.35

 

Anti-inflammatory drugs (eg, diclofenac) may be used systemically and locally.

 

Injections in the joint should be restricted to single cases. A single shot of corticosteroids may lead to pain relief.

 

Cooling devices also inhibit the inflammation process.

 

Orthotic devices such as stiff inserts for shoes or rocker bottom soles take pressure from the MTP joint by facilitating the scrolling process. To further alleviate pressure on the joint, a shoe with a roomy toe box should be worn and high heels should be avoided.

 

Physical therapy helps keep the joint mobile.

 

The question is whether immobilizing the joint by orthotics or stiff insoles in early arthritis is a reasonable approach because doing so results in the functional breakdown of the MTP joint. In our practice, we prefer to keep the joint mobile by physical therapy and manual therapy and by having the patient perform exercises for dorsiflexion and plantarflexion daily (eg, aqua jogging on tiptoes).

 

We have found that chondroitin and glucosamine sulfate, slow-acting drugs for the treatment of osteoarthritis,21,34 have comparable success in improving the pain and symptoms of osteoarthritis.

 

Additional nonsteroidal anti-inflammatory drugs and ice can be applied to support progress at the beginning of the physical therapy program.

 

 

 

 

FIG 2 • A. Postoperative radiograph of first MTP joint prosthesis. B,C. Osteochondral autograft transplantation from the plantar medial talus.

 

SURGICAL MANAGEMENT

 

The goal of surgical treatment is to achieve a pain-free joint.

 

 

Several surgical approaches have been proposed in the literature, including resection arthroplasty,7,22,23,30 interpositional arthroplasty,2,19,24 MTP replacement (implant arthroplasty),11,39 arthrodesis,18,28,32 and cheilectomy.13,18,20,25,27

 

After its first description by DuVries13 in 1959, cheilectomy emerged as the most popular choice for surgical intervention. Indications for performing a cheilectomy are controversial.10,14 Some authors recommend cheilectomy as a treatment for lower grades only,17,18,20,31 whereas others have reported successful results even for higher grades of the disease.14,15,27

 

Cheilectomy resects the dorsal obstacle but does not address the plantar pathology, which includes tremendous shortening of the plantar capsular, as well as the short flexors and plantar osteophytes of the phalangeal base.

 

Cheilectomy alone without plantar release, in our opinion, cannot be successful.

 

A remaining cartilage lesion also may be responsible for persistent symptoms. This observation led to our idea of stimulating fibrocartilage regeneration by microfracturing the subchondral bone with a specially designed awl to open the zone of vascularization.

 

Steadman et al38 has developed a microfracture technique for the knee that creates fibrocartilage in chondral lesions.

 

 

It has been shown to be effective in comparison to untreated lesions in experimental studies in horses16 and in clinical studies of the knee33,37,38 and talus.4

 

Coughlin and Shurnas type 2 and 3 lesions are indications for the microfracture technique.

 

 

In type 3 lesions, the patient must be informed that the surgery has only limited success.

 

A contraindication for cheilectomy with microfracture is the stiff joint of types 3 and 4 osteoarthritis. In this case, in patients with a low activity level who want good ROM, a resurfacingtype prosthesis (not a “head resection” type) is a good alternative and is being used with increasing frequency (FIG 2A).

 

Patients with isolated, painful osteochondral lesions without degenerative joint disease may be considered in rare cases for microfracture alone (for a small, contained lesion) or for an osteochondral transplantation from the plantar medial talus (FIG 2B,C).

 

 

 

Preoperative Planning

52

 

Standard weight-bearing AP and lateral radiographs as well as, in some cases, MRI evaluation should be performed for grading the patient according to the Coughlin and Shurnas classification, and the cartilage damage should be assessed.

 

The clinical examination should include measurement of active and passive ROM and determination of power in extension and plantarflexion, along with a dynamic stress test for evaluation of sesamoid pathology.

 

Positioning

 

The patient is placed supine on the operating table.

 

General or local anesthesia may be used, according to the setup and the surgeon's preference.

 

A pneumatic tourniquet or Esmarch bandage should be used.

TECHNIQUES

• Exposure

A 4- to 5-cm incision is made anteromedially (TECH FIG 1A), being careful to protect the dorsal nerve above the first metatarsal head.

The fatty tissue and the subcutaneous tissue are dissected, and the joint capsule is prepared.

 

 

 

 

TECH FIG 1 • A. Anteromedial approach. B,C. Joint exposure from the lateral side showing the restriction in plantarflexion.

 

 

 

The extensor hallucis longus tendon is retracted and the joint exposed (TECH FIG 1B,C). The joint is then inspected by flexing the great toe in the plantar direction.

• Cheilectomy

   

   

  After inspection of the joint, the dorsal osteophytes on the base of the proximal phalanx are removed. Cheilectomy is performed with an oscillating saw.

   

  The cut is performed in line with the dorsal metatarsal shaft.

   

  The resection must not exceed about 15% to 20% of the metatarsal head (TECH FIG 2A) because this leads to a jerking motion of the toe.

   

   

   

  TECH FIG 2 • A. Cheilectomy. B. Resection of remaining osteophytes.

   

   

  Osteophytes remaining on the medial and lateral facet of the joint are removed with a sharp rongeur, plantarflexing the proximal phalanx (TECH FIG 2B).

   

  The rims are smoothed with a rasp.

   

   

   

• Extensive Plantar Release

  53

   

  Release of the plantar structures is very important for improving the ROM.

   

  Because of the inhibition of dorsiflexion in the first MTP joint, contracture of the plantar structures (joint capsule, short toe flexors) has taken place.

   

  The joint capsule and the short flexors with the sesamoid bones are released subperiosteally using a McGlamry elevator (TECH FIG 3A,B).

   

  The phalangeal attachment of the plantar capsule and the insertion of the short flexor muscles are released (TECH FIG 3C).

   

  This maneuver must be performed cautiously so as not to detach the tendons from their insertion.

   

   

   

  TECH FIG 3 • A. Plantar release using a McGlamry elevator. B. Plantar release using a McGlamry elevator. C. Release of the distal capsule and short flexors using a scalpel. D. Plantarflexion after plantar release and resection of osteophytes.

   

   

  The joint is inspected again for plantar osteophytes of the phalangeal base and unstable cartilage parts, which will be resected.

   

   

  Further resection to the metatarsal head must be avoided to prevent joint instability. The rims are smoothed again with a rasp.

   

  Osteophytes at the proximal sesamoid site must be resected because this also is a source for plantar pain and restricted dorsiflexion (TECH FIG 3D).

• Microfracture

   

  The remaining cartilage lesions at the first MTP joint or the proximal phalanx must be débrided of all remaining unstable cartilage and fibrous tissue.

   

  The calcified cartilage layer must be completely removed.

   

  Using an awl, the microfractures are placed approximately 1 to 2 mm apart and about 2 to 4 mm deep (TECH FIG 4).

   

   

   

  TECH FIG 4 • Microfracturing of the metatarsal head.

   

   

   

• Wound Closure

  54

   

  The joint capsule is closed with interrupted absorbable sutures, and a 0.8-mm drain is placed between the capsule and the continuous subcutaneous suture.

   

  The skin is sutured intracutaneously.

   

  Infiltration of the skin with bupivacaine and morphine decreases pain and need for pain killers after surgery.

   

  A small splint, which fixes the joint in dorsiflexion, is important to stretch the released shortened plantar structures (TECH FIG 5).

   

   

   

  TECH FIG 5 • Splint in 40 degrees dorsiflexion.

• Case Example 1 (Courtesy of Mark E. Easley, MD)

  Background and Physical Examination

   

   

  Hallux rigidus may develop from an osteochondral defect to the metatarsal head. Rarely are we able to identify these early stages of first MTP joint arthritis.

   

  A 25-year-old woman who had 6 months right great toe pain. She had a remote history of a right great toe impaction injury/sprain.

   

   

  Ache in right great toe with ROM Sharp pain with push-off during gait

   

   

  Occasional catch/click in the first MTP joint Swelling in the first MTP joint

   

  Hallux alignment was well maintained.

   

   

  ROM is well maintained with minimal to no dorsal impingement. Mild edema/effusion in first MTP joint

   

   

  Mild pain with great toe ROM, including at midrange of motion arc Occasional mechanical click with ROM

  Imaging

   

  Radiographs

   

  Well-maintained joint space and alignment

   

  No advanced arthritic changes or osteophytes

   

   

  No obvious loose body MRI

   

   

  Cartilage surfaces without advanced wear pattern suggested Signal change in first metatarsal head cartilage

  Surgical Management

   

   

  Dorsomedial longitudinal incision over first MTP joint Protect dorsomedial sensory cutaneous nerve to the hallux.

   

   

  Protect the extensor hallucis longus tendon. Dorsal capsulotomy to expose first MTP joint

   

   

  Joint inspection reveals large central osteochondral defect (TECH FIG 6A). Flap of unstable central cartilage (TECH FIG 6B)

   

   

   

  Débridement of unstable cartilage Microfracture (TECH FIG 6C) Capsular and wound closure

  Postoperative Care

   

  First 6 weeks:

   

   

  Protected weight bearing in postoperative shoe Gentle passive first MTP joint ROM

   

  Next 6 weeks, gradually advance activities to return to full activities.

   

   

   

  TECH FIG 6 • A. Central chondral flap reduced. (continued)

   

   

  55

   

   

   

  TECH FIG 6 • (continued) B. Instability of central chondral flap demonstrated by elevation on its medial “hinge.” C. Microfracture for first metatarsal head central chondral defect.

• Case Example 2 (Courtesy of Mark E. Easley, MD)

 

Similar presentation as Example Case 1

 

 

A 39-year-old woman with left first MTP joint pain, ache, and occasional sharp pain Remote history of first MTP joint injury

 

Pain with first MTP joint ROM but no dorsal impingement

Imaging

 

Radiographs

 

Well-maintained joint space and alignment

 

 

No advanced arthritic changes or osteophytes No obvious loose body

 

MRI

 

 

Cartilage surfaces without advanced wear pattern suggested Signal change in first metatarsal head cartilage

Surgical Management

 

Approach same as Example Case 1

 

Central defect in articular cartilage noted with unstable cartilage (TECH FIG 7A)

 

 

 

TECH FIG 7 • A. Central chondral defect. B. Central chondral defect débrided to stable cartilage rim.

(continued)

 

 

 

Débridement of unstable cartilage to stable residual cartilage rim (TECH FIG 7B). Microfracture (TECH FIG 7C)

 

 

In this case, central defect filled with commercially available allograft cartilage (TECH FIG 7D,E) Contains extracellular matrix, including type II collagen, proteoglycans, and growth factors

 

Fibrin glue to seal the defect and contain the extracellular matrix (TECH FIG 7F,G) Postoperative Care

 

 

Similar to Example Case 1 but with more gradual return to full activities First 6 weeks:

 

 

Protected weight bearing in postoperative shoe Gentle passive first MTP joint ROM

 

Next 12 weeks: Gradually advance activities to return to full activities.

 

 

56

 

 

 

TECH FIG 7 • (continued) C. Microfracture for central defect, performed with a small joint microfracture awl.

D. Central chondral defect being filled with commercially available allograft cartilage. E. Allograft cartilage filled to match the native first metatarsal head cartilage. F. Fibrin glue to seal the allograft cartilage within the defect. G. Appearance immediately prior to closure. No shear by first proximal phalanx on filled first metatarsal head defect.

 

 

PEARLS AND PITFALLS
	Resection of the metatarsal ▪ Do not exceed 20% of the metatarsal head circumference. head ▪ Too much resection may lead to instability of the joint.     Plantar release of flexor ▪ Rough detachment of the short flexors may result in weak tendons plantarflexion.

 

	Using the McGlamry raspatory, a distinct sound must be heard and felt.

 

 

 

 

POSTOPERATIVE CARE

57

 

After surgery, a gauze-and-tape compression dressing is applied to the wound and the hallux is fixed in 30 to 40 degrees dorsiflexion with a plantar cast for 2 days to support plantar release and to improve immediate ROM after surgery.

 

A second-generation cephalosporin is prescribed for 5 days. Dexamethasone is given for 4 days, according to this schedule: day 1, 4 mg; day 2, 8 mg; day 3, 4 mg; and day 4, 2 mg.

 

 

This regimen provides protection from infection, and the dexamethasone provides significant reduction of pain and swelling, which helps to restore ROM.

 

It also prevents excessive scar formation, which may result in recurrent loss of motion.

 

The first dressing change, with removal of the drain, occurs on the second postoperative day.

 

In our practice, from the second day, patients wear a postsurgical shoe with full weight bearing for 2 weeks to reduce loading and its accompanying pain and swelling. This allows the patient to become pain free more quickly and makes it possible to regain dorsiflexion earlier (FIG 3).

 

 

The shoe permits good mobility and excellent conditions for decreased swelling and improved wound healing.

 

“Aggressive” treatment of pain and swelling is crucial for the success of the surgical procedure because regaining and stabilizing the intraoperatively attained ROM is the postsurgical goal.

 

Passive and active ROM exercises are started from the second day if wound conditions and pain permit.

 

 

After removal of skin sutures, aggressive stretching is necessary to maintain ROM.

 

 

At this point, the patient should walk without the postsurgical shoe, focusing on a normal gait. The rehabilitation program also includes isometric and proprioceptive training.

 

Cooling, nonsteroidal anti-inflammatory drugs, and physical therapy with joint distraction support the daily self-guided dorsiflexion exercises.

 

At 3 to 4 months, the maximum ROM usually has been achieved. The patient must be aware that there is only a limited time frame for achieving good motion.

 

OUTCOMES

In a prospective study, 36 patients (26 women and 10 men) with 37 cases of hallux rigidus were operated by the senior author (HT) using the described technique.3

Patients were examined and interviewed preoperatively as well as 1 year (mean 12 monts; 28 cases) and 2 years (mean 23 months; 22 cases) postoperatively and rated using the American Orthopaedic

Foot and Ankle Society (AOFAS) hallux MTP-interphalangeal score31 and by a visual analog scale

 

 

(VAS; not scaled 10 cm, where 0 is very poor and 10 is excellent).

 

 

 

FIG 3 • This shoe reduces load to the forefoot.

 

 

The average age of the 36 patients at the time of surgery was 50 years (range 31 to 64 years).

 

Preoperative radiographs following Hattrup and Johnson's classification revealed 25 cases of grade 2 and 12 of grade 3. No patient was classified as grade 1.

 

Two patients, both grade 3, refused the follow-up examination.

 

According to the AOFAS score, the results revealed a significant improvement from 43 points preoperatively to an average of 78 points (range 35 to 100 points) after both 1 and 2 years postoperatively.

 

The average outcome on the VAS after 2 years was 7.1 for pain (preoperatively: 2.2; after 1 year: 7.0),

7.1 for function (preoperatively: 2.8; after 1 year: 6.7), and 7.4 for satisfaction (preoperatively: 1.1; after

1 year: 6.6).

 

Clinical examination showed an average improvement in ROM of 22 degrees.3

 

Patients classified as grade 3 were found to have significantly poorer results on average than grade 2.

 

Retrospectively, several of our patients would have been classified as grade 4 and, we now believe, should not have been considered for cheilectomy. We believe grade 3 is an indication if microfracturing and plantar release are added for treatment and the joint was not stiff before surgery.

 

COMPLICATIONS

In patients with coexisting hallux valgus deformity, correction of the axis with a soft tissue release is essential for a successful result. However, the obligatory immobilization of the osteotomy reduces the options for postoperative management and results sometimes are less successful in regaining ROM.

If too much metatarsal head is resected with the cheilectomy, first MTP joint instability may ensue. Rough detachment of the short flexors may result in weak plantarflexion.

 

 

 

REFERENCES

1. Ahn TK, Kitaoka HB, Luo ZP, et al. Kinematics and contact characteristics of the first metatarsophalangeal joint. Foot Ankle Int 1997;18:170-174.

    

    

2. Barca F. Tendon arthroplasty of the first metatarsophalangeal joint in hallux rigidus: preliminary communication. Foot Ankle Int 1997;18:222-228.

    

    

3. Becher C, Kilger R, Thermann H. Results of cheilectomy and additional microfracture technique for the treatment of hallux rigidus. Foot Ankle Surg 2005;3:155-160.

    

    

4. Becher C, Thermann H. Results of microfracture in the treatment of articular cartilage defects of the talus. Foot Ankle Int 2005;26:583-589.

    

    

5. Bingold AC, Collins DH. Hallux rigidus. J Bone Joint Surg Br 1950; 32-B(2):214-222.

    

    

6. Bonney G, Macnab I. Hallux valgus and hallux rigidus; a critical survey of operative results. J Bone Joint Surg Br 1952;34-B(3):366-385.

    

    

7. Brandes M. Zur operativen Therapie des Hallux valgus. Zbl Chir 1929;56:2434-2440.

    

    

8. Cotterill JM. Condition of stiff great toe in adolescents. Edinburgh Med J 1887;33:459-462.

    

    

9. Coughlin MJ, Shurnas PS. Hallux rigidus: demographics, etiology, and radiographic assessment. Foot Ankle Int 2003;24:731-743.

    

    

10. 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.

     

     

    58

     

11. Cracchiolo A III, Swanson A, Swanson GD. The arthritic great toe metatarsophalangeal joint: a review of flexible silicone implant arthroplasty from two medical centers. Clin Orthop Relat Res 1981; (157):64-69.

     

     

12. Davies-Colley N. Contraction of the metatarsophalangeal joint of the great toe. Br Med J 1887;1:728.

     

     

13. DuVries HL. Surgery of the Foot. St. Louis: Mosby, 1959.

     

     

14. Easley ME, Davis WH, Anderson RB. Intermediate to long-term follow-up of medial-approach dorsal cheilectomy for hallux rigidus. Foot Ankle Int 1999;20:147-152.

     

     

15. Feltham GT, Hanks SE, Marcus RE. Age-based outcomes of cheilectomy for the treatment of hallux rigidus. Foot Ankle Int 2001;22: 192-197.

     

     

16. Frisbie DD, Trotter GW, Powers BE, et al. Arthroscopic subchondral bone plate microfracture technique augments healing of large chondral defects in the radial carpal bone and medial femoral condyle of horses. Vet Surg 1999;28:242-255.

     

     

17. Geldwert JJ, Rock GD, McGrath MP, et al. Cheilectomy: still a useful technique for grade I and grade II hallux limitus/rigidus. J Foot Surg 1992;31:154-159.

     

     

18. Gould N. Hallux rigidus: cheilotomy or implant? Foot Ankle 1981; 1:315-320.

     

     

19. Hamilton WG, O'Malley MJ, Thompson FM, et al. Roger Mann Award 1995. Capsular interposition arthroplasty for severe hallux rigidus. Foot Ankle Int 1997;18:68-70.

     

     

20. Hattrup SJ, Johnson KA. Subjective results of hallux rigidus following treatment with cheilectomy. Clin Orthop Relat Res 1988;(226):182-191.

     

     

21. Hua J, Sakamoto K, Kikukawa T, et al. Evaluation of the suppressive actions of glucosamine on the interleukin-1beta-mediated activation of synoviocytes. Inflamm Res 2007;56:432-438.

     

     

22. Keller WL. The surgical treatment of bunions and hallux valgus. N Y Med J 1904;80:741-742.

     

     

23. Kessel L, Bonney G. Hallux rigidus in the adolescent. J Bone Joint Surg Br 1958;40-B(4):669-673.

     

     

24. Lau JT, Daniels TR. Outcomes following cheilectomy and interpositional arthroplasty in hallux rigidus. Foot Ankle Int 2001;22:462-470.

     

     

25. Mann RA, Clanton TO. Hallux rigidus: treatment by cheilectomy. J Bone Joint Surg Am 1988;70(3):400-406.

     

     

26. Mann RA, Coughlin MJ, eds. Surgery of the Foot and Ankle. St. Louis: Mosby, 1993.

     

     

27. Mann RA, Coughlin MJ, DuVries HL. Hallux rigidus: a review of the literature and a method of treatment. Clin Orthop Relat Res 1979;(142):57-63.

     

     

28. McKeever DC. Arthrodesis of the first metartarsophalangeal joint for hallux valgus, hallux rigidus, and metatarsus primus varus. J Bone Joint Surg Am 1952;34-A(1):129-134.

     

     

29. Meyer JO, Nishon LR, Weiss L, et al. Metatarsus primus elevatus and the etiology of hallux rigidus. J Foot Surg 1987;26:237-241.

     

     

30. Moberg E. A simple operation for hallux rigidus. Clin Orthop Relat Res 1979;(142):55-56.

     

     

31. Mulier T, Steenwerckx A, Thienpont E, et al. Results after cheilectomy in athletes with hallux rigidus. Foot Ankle Int 1999;20:232-237.

     

     

32. Ogilvie-Harris DJ, Carr MM, Fleming PJ. The foot in ballet dancers: the importance of second toe length. Foot Ankle Int 1995;16:144-147.

     

     

33. Pässler HH. Die Technik der Mikrofrakturierung für die Behandlung von Knorpelschäden. Zentralbl Chir 2000;125:500-504.

     

     

34. Reginster JY, Deroisy R, Rovati LC, et al. Long-term effects of glucosamine sulphate on osteoarthritis progression: a randomised, placebocontrolled clinical trial. Lancet 2001;357:251-256.

     

     

35. Smith RW, Katchis SD, Ayson LC. Outcomes in hallux rigidus patients treated nonoperatively: a long-term follow-up study. Foot Ankle Int 2000;21:906-913.