Introduction
This condition was first described in 1887 by Davies-Colley,1 who used the term Hallux flexus in referring to the planter flexed posture of the phalanx relative to the metatarsal head. In 1888, Cotterill 2 used the term “Hallux Rigidus” to describe a degenerative disease of the first metatarsophalangeal joint with stiffness and deformity. There have been several descriptions of this condition by other authors. Functional Hallux limitus 3 describes biomechanical features of the joint, which effectively limits dorsiflexion, with no degenerative changes present.
Biomechanics of the 1st MTP Joint
In the neutral position the average surface contact area is 0.38 cm2. 4 The average joint surface area of contact decreases as the proximal phalanx dorsiflexes on the 1st metatarsal head. At full dorsiflexion it decreases to 0.04cm2.4 The contact point on the 1st metatarsal head shifts dorsally, with increasing toe dorsiflexion, but the contact point on the proximal phalanx articular cartilage remains the same. 4 This fits with the chondral erosion and degeneration that are described on the dorsal aspect of the joint in Hallux Rigidus in adolescents.5
Epidemiology
It is the second most common condition affecting the 1st MTP joint but is associated with greater pain than Hallux valgus.5 Hallux rigidus has been described in two different age groups. The adolescent form is associated with osteochondritis dessicans. 6 The cause of the adult form is elusive but is thought to be a continuum of the adolescent form by some authors.7 The mean age of occurrence is 43 years (from adolescence to the ninth decade).7
Eighty percent of the first presentations are unilateral. 8 At first presentation, the patients have an asymptomatic dorsal osteophyte and/or reduced dorsiflexion of the Hallux. A higher male involvement has been reported in those over 30 years complaining of Hallux Rigidus, but most studies have shown an overwhelming higher incidence of female involvement in those seeking surgical repair.8 A history of trauma is more common in females with 78% of unilateral HR associated with trauma. 8 The risk of bilateral disease increases with a positive family history.9 It is thought that family history may predispose to early onset9. There is no association with footwear or occupation.
Aetiology
Trauma
A single traumatic episode (intra-articular fracture, crush injury) or repetitive micro-trauma may be at the origin of osteoarthritic changes. Forced planter flexion or dorsiflexion may result in jamming and development of an acute chondral or osteo-chondral injury. 10 In the adolescent patient there is often a dorsal osteo-chondral lesion, which may only be diagnosed on MRI scan. 10
Biomechanical
A number of biomechanical causes had been identified and these include Functional Hallux Limitus, Functional hypermobility, Gastrocnemius-soleus equinus, compensated forefoot valgus. 11 Tendo-Achilles, or gastrocnemius tightness, has been reported in 25% of patients with Hallux Rigidus but there does not appear to be different from the normal population. 11
There are three variations in the shape of the metatarsal head, (the oval, the chevron and the flat). The flat type is associated with resistance of lateral pressure and increased incidence of Hallux Rigidus.12
Structural
Structural causes include: Metatarsus primus elevates (MTPE); Long first metatarsal and long proximal phalanx of Hallux. Lumbrinudi first proposed a hypermobile first metatarsal, with an excess range of dorsiflexion. In 1938, Roukis13 showed that as the first ray moves from neutral to dorsiflexion, the amount of dorsiflexion of the first MTPJ decreases by 19% with 4mm dorsiflexion, and 35% with 8mm dorsiflexion. 13 However, no serious study has demonstrated that hypermobile first ray or metatarsus primus elevatus predisposes to Hallux Rigidus compared to people with normal rays. Roukis found a slight increase of this condition in patients with Hallux Rigidus compared with other foot diagnoses, but did not include a control group.14 Although MTPE is more common in Hallux rigidus, it has not been proven that planter flexion osteotomies, correcting this condition are of any value. 14
Latrogenic
These include: post-surgical excessive elevation of the 1st M, excessive lengthening of the 1st MT, misalignment of the 1st MTPJ, excess fibrosis and seasamoid dysfunction and prolonged immobilisation.
Others causes
It is also worth mentioning, gouty arthritis, septic arthritis, muscle imbalance affecting first ray.
Pathogenesis Diagram
The cause of HR has not been determined although many predisposing factors have been cited. It may be secondary to trauma, gout, infection or other inflammatory arthropathy. Degeneration may begin dorsally with limitation of dorsiflexion and impingement as the predominant features or begin as a central crater spreading to the whole joint.
Clinical presentation
History
The commonest features are pain and stiffness. In the early period, pain is mainly felt dorsally and is provoked by dorsal impingement. It is later situated in the joint and provoked by movement at any point in the range. It may present as mainly planter pain, probably due to seasamoid-metatarsal osteoarthritis. A prominent dorsal osteophyte may cause rubbing in shoes. There is usually a bursa and skin may have abrasions causing pain. Few patients complain of stiffness and compensatory hyperextension of the IP joint, which often develops with increased stiffness of the MTPJ.16 A feeling of “locking” due to synovial impingement or osteo-chondral lesions. There may be nerve symptoms due to irritation of the digital nerve.
The patient may have functional demands, which could have a major influence on his management: A labourer needs a pain-free toe even if stiff. An athlete needs mobility and may be ready to put up with residual pain. We should look out for systemic conditions such as gout or rheumatoid arthritis.
Clinical examination
The patient usually walks with a gait avoiding toe-off, and walking mainly on the lateral aspect of the foot. There is an antalgic component with hurrying the toe-off component of the gait, due to pain on the lateral metatarsals and the lateral border of the foot. Look for any prominences, signalling osteophytes, bunion and any skin changes, especially on the medial aspect of the MTPJ. Identify sites of tenderness and evaluate the rigidity and the residual arc of movement.
Look for the cause of pain: on dorsiflexion, on planter flexion or throughout the movement. Pain on extremes of movement is usually associated with mild to moderate Hallux Rigidus, while pain throughout the arc of movement is due to severe Hallux valgus.16, 17 You should check the alignment, hyperextension of the Interphalangeal joint and for an associated Hallux Valgus deformity.
Imaging
Standard weight-bearing AP, Lateral: Joint narrowing, subchondral sclerosis, widening or flattened metatarsal head, osteophytes, spurs, loose bodies, metatarsus adductus, Hallux valgus, Hallux valgus interphalangeus, dorsal spurring at the first Tarso-metatarsal joint and talo-navicular joint. Evaluate the metatarsal-seasamoid articulation, which may be involved in severe arthritis. MRI may be necessary in cases of suspected Osteochondritis if X-rays appear normal.
Classification
Several different attempts have been made to classify Hallux Rigidus. A classification scheme is helpful in standardising the terminology both for describing magnitude of arthritic changes and recommending treatment. A clinical/radiographic grading system was described by Regnauld and appears mainly in the European literature. 16,17
Roukis suggested a classification based on both biomechanical features and X-ray criteria18 derived from the systems of Drago, Hanft and Kravitz.19 This is called the Modified Hybrid Grading System for Hallux Rigidus.18 It has four stages: Stage 1; Functional Limitus; stage 2 early joint adaptations; stage 3; Established arthritis and stage 4; Ankylosis.
Management
Non-Surgical:
NSAIDS can be useful in the initial stages; Ice is a useful adjuvant therapy. Activity modification may be needed.20 Some patients find steroid injections useful in the short or medium term. Pons et al (2007) reported a single blind RCT comparing steroid with hyluronan injections. The hyluronan group had better AOFAS scores but there were no other major differences.21 Grady et al (2002) reported that 56% of 772 patients with Hallux Rigidus were successfully treated non-operatively, using a combination of orthoses, shoe alterations and steroid injections. 22
Functional Orthotics
The goal of the functional orthotics is to improve first ray function by enhancing stability and limiting dorsiflexion of the ray. The design of the orthotic should allow the first metatarsal to maximally planter flex. This allows the first metatarsal to be in a more relative dorsiflexion position towards the latter stages of stance.23 Less abnormal motion will take place at the first metatarsophalangeal joint and there will be less sudden abutment at the dorsal aspect of the joint. Functional orthoses modified for Hallux Rigidus include inverted cast correction; medial heel skive and deep heel cup. Forefoot modifications include reverse Morton’s padding; sesamoid accommodation; kinetic wedge and other techniques to off load the first ray.23,24
Surgical Treatment
Surgical solutions will be needed if non-operative treatment fails to relieve pain especially in the stages 3 and 4 Hallux Rigidus. Several surgical solutions are used including cheilectomy; Osteotomies, Arthrodesis and Arthroplasty.
Cheilectomy
Dorsomedial, (most used) medial (Man et al) or dorso-lateral incision have been used with equivalent results.25 Adequate debridement must be achieved to allow for 70o dorsiflexion on the table. In one study, Heller et al (1997) showed that a 30% excision of the metatarsal head as recommended by Mann (1988), adequately increases the range of movement in Hallux Rigidus.26
The largest series and the longest follow-up (10 years), was by Coughlin (2003). 27 He distinguished between patients with severe radiographic change but no mid-range pain (in whom cheilectomy was successful in 32/34 patients and the mean AOFAS score was 90) and those with severe changes and mid-range pain, in whom only 1/9 patients who chose cheilectomy got a satisfactory result. In another long-term study by Waizy (2009), 20/20 patients in grade 1, 23/35 patients in grade 2 and 4/5 patients in grade 3 had little or no pain at seven to nine years, although the overall patient satisfaction was lower. 28
Cheilectomy does not restore the normal joint kinematics. Nowoczenski (2008) found that the range of dorsiflexion was increased, but only to 31° during gait but remained planter flexed during static stance.29 Cheilectomy has a definite role in treatment of mild to moderate Hallux Rigidus and is the treatment of choice in this group. Comparative trials with osteotomies of the phalanx and metatarsal would be useful in evaluating definitive best therapy. It is acceptable in grade 3 Hallux Rigidus, where movement needs to be preserved but a higher rate of failure could be expected.
Osteotomies
Dorsiflexion, phalangeal osteotomies – This procedure is possible in patients with reasonable residual range of motion. A dorsal wedge osteotomy of the phalanx (Morberg procedure) increases dorsiflexion but may limit planter flexion. Four series with small numbers with follow-up of over ten years have reported satisfactory pain relief in 70-100%.30 Dorsiflexion is also found to increase by an average of 10%.30 No comparative study against cheilectomy has been carried out.
Metatarsal Osteotomy – The concept of metatarsus primus elevatus is thought to be a major aetiological factor in the development of Hallux Rigidus. Procedures to correct elevation of the metatarsal head often with shortening of the metatarsal to decompress the joint have been used. Distal and proximal osteotomies are used. The Youngswick procedure is basically a modification of the chevron Osteotomy with a slice removed on the dorsal limb to slide the head down and proximally31. Straight or oblique osteotomies of the head similar to Weil procedure are carried out. The Waterman-Green Osteotomy removes a wedge from the dorsum of the metatarsal head, aiming to rotate the better cartilage on the lower part of the head up into the metatarsal-phalangeal articulation31.
The place for metatarsal osteotomies in the management of Hallux Rigidus is uncertain. Roukis et al (2003), Gonzales et al (2004) have published results with short-term follow-up. These results are comparable to those of the cheilectomy, which is a simpler operation.31
Arthrodesis
Several techniques are being carried out to fuse the first Metatarsophalangeal joint. Cannulated ball-and-socket reamers or simple use of burr, drill and rongeurs, produce a surface that can be approximated for fusion. Fusion with dorsiflexion allowing pulp of the toe just off the surface with the foot plantigrade is the position of choice of most surgeons.
Many different fixation techniques abound including staples, one or two screws, and low profile plates. In a cadaveric study, Politi found the most stable construct to be screws and a dorsal plate.32 However the plate was found to be twice as costly as two cross screws without a difference in union rate, time or complications.32 Sharma found no difference in union or complication rates between single screw and a lag screw and plate.33
First metatarsal fusion is still the gold standard for advance Hallux Rigidus. There is however insufficient comparative data of this technique and the other techniques.
Arthroplasty:
Capsular arthroplasty – This technique has been described by Hamilton et al (1997) and includes limited resection of the proximal phalanx and suture of the dorsal capsular flap to the plantar structures34. Seth et al (2006) found successful outcomes at 22 months in 82% of their patients with grade 3 Hallux Rigidus treated by this technique 35. They concluded that this treatment was indicated for patients who wanted to retain motion including athletes and women who want to wear high heel shoes but that it is a temporary ‘fix’ 35.
Total Joint Replacement
There is evidence of gait abnormality following fusion (Brodsky 2007)36 and it is hoped that replacement will protect the other joints from abnormal strains and degeneration. Replacement of the Metatarsophalangeal joint has not been established as a standard care for osteoarthritis of Hallux Rigidus as yet.
a) Silicon Prosthesis.
Second generation silastic prosthetics used double-stem silicone implants protected by titanium grommets. Clinical results with these were better than the first generation and radiological analysis showed no evidence of implant fracture. Yee and Lua (2008).37 However, there is concern about silicone debris causing foreign body reaction and synovitis.37
b) Metal on Plastic
Most series use the dorsal approach, clearing the osteophytes first. There are not many studies on MTPJ total joint replacements specifically for Hallux Rigidus. Fuhrmann et al (2003) in a three-year follow-up of Metatarsophalangeal joint, total joint replacement for end-stage Hallux Rigidus found that 1/3 of the prosthesis showed signs of implant loosening.38 They concluded that although this procedure offered distinct advantages in the treatment of end-stage Hallux Rigidus, further research is required on implant design and osseous fixation.
c) Ceramic total joint replacement (MOJE).
The Moje ceramic press-fit prosthesis (Orthosonics Ltd), was first placed on the market in December 1999. Several studies have been published on early, mid-term and long-term outcomes using the MOJE. Kulshreshtha et al (2007)39 in medium to long-term assessment showed early radiologic loosening. They advised caution on the use of this implant. Chueng et al in a prospective consecutive series for 24 months found good early outcomes40 but other authors found that this implant offers less reliable outcomes than the ‘gold standard’ Arthrodesis and advised caution regarding its use for osteoarthritis of the first MTPJ 41.
d) Metal Hemiarthroplasty
Metallic Hemiarthroplasty can offer a cautious option for grade 3 Hallux Rigidus, for patients who want to retain movement. Aronow et al (2006) using Biopro implant on 20 patients, at a follow-up of 49 months, found that although there was an 81% satisfaction rate, the procedure does not restore range of motion to normal and patients experience persistence discomfort 57. There needs to be adequate cheilectomy performed at the time of the implantation.
In our practice, we have found this operation fairly successful in Stage III and IV Hallux Rigidus in the short and medium terms.
e) Excisional Arthroplasty:
First described by Davies-Colley (1887) and popularised by Keller (1904). The Metatarsophalangeal joint is decompressed by resecting the base of the proximal phalanx, therefore relaxing contracted soft tissues. This relieves pain and has been accepted for more advanced degenerative arthritis. It is indicated in older, more sedentary patients, household ambulators with grade 3 and 4 Hallux Rigidus.
Conclusion
The Hallux Rigidus is an important and frequent condition of the first MTPJ. It poses important challenges with regards to the aetiology, patho-mechanics and treatment options. Cheilectomy appears to be simple and most successful in early stages. While arthrodesis is considered the gold standard for the management of severe Hallux Rigidus, there is a problem in patients who wish to have preserved movement of the joint. For this cohort of patients, there has not been a significant positive results with the use of present implants. It is hoped that with the advancement in implant technologies, more lasting and favourable outcomes will be found.
References:
1. Davies-Colley M. Contraction of the metatarsophalangeal joint of the great toe. Br Med J; 1887, 1: 728
2. Cotterill J: Stiffness of the great toe in adolescents. Br Med J; 1888; 1: 1158
3. Laird PO. Functional Hallux Limitus. Illinois Pidiatrists 9 (4)
4. Ahn TK, Kitaoka HB et al. Kinematics and contact characteristics of the first metatarsophalangeal joint. Foot and Ankle Int 1997; 18(3): 170-4
5. Roukis TS, Jacobs PM et al. A prospective comparison of clinical, radiographic and intra-operative features of Hallux Rigidus. J Foot Ankle Surg: 2002; 41(2): 76-
6. Thomas AP, Dwyer NS: Osteochondral defects in the first metatarsal head in adolescence: a stage in development of Hallux rigdus. J Peadiar Orthop 1989; 9:236-239.
7. Gould N, Schneider T: Epidemiological survey of foot problems in the continental United States: 1978-1979. Foot Ankle, 1980; 1:8-10.
8. Roukis TS, Jacobs PM et al. A prospective comparison of clinical, radiographic and intra-operative features of Hallux Rigidus. J Foot Ankle Surg: 2002; 41(2): 76-95.
9. Camasta CA. Hallux Limitus and Hallux Rigidus. Clinical examination, radiographic findings, and natural history. Clin Podiatr Med Surg 1996; 13(3): 423-48.
10. Clanton TO, Ford JJ: Turf injury. Clin Sports Med 1994; 13:731-741.
11. Roukis TS et al. Position of the first ray and motion of the first metatarsophalangeal joint. J Am Podiatr. Med Assoc 1996; 86(11): 538-46.
12. Coughlin MJ and Shurnas PS. Hallux Rigidus: demographics, etiology and radiographic assessment. Foot and Ankle Int. 2003; 24(10): 731-43.
13. 84 book
14. Roukis TS, Jacobs PM et al: A prospective comparison of clinical radiographic and intraoperative features of hallux Rigidus. J Foot Ankle surg. 2002; 41(2): 76-95
15. Vanore JV, Christensen JC et al. Diagnosis and treatment of first metatarsophalangeal joint disorders. Section 2: Hallux Rigidus. J foot Ankle Surg 2003; 42(3): 124-136.
16. Prubit S : Challenging Running Injuries. Podiatric Management. January, 2010 (in press).
17. Vanore JV, Christensen JC et al. Diagnosis and treatment of first metatarsophalangeal joint disorders. Section 2: hallux Rigidus. 2003; J Foot Ankle Surg 42(3):124-136.
18. Coughlin MJ, Shurnas PS: Clinical and radiological classification of Hallu Rigidus. J Bone Joint Surg Am 85(11): 2072-2088, 2003
19. Drago JJ, Oloff L et al. A comprehensive review of hallux Limitus. J foot Surg 23(3): 213-220, 1984.
20. Hanft JR, Mason ET et al. A new radiographic classification for hallux Limitus. J Foot Ankle Surg. 32(4): 397-404, 1993.
21. Kravitz SR, LaPorta GA, Lawton J. Progressive staging classification of hallux Rigidus. Lower Extremity 1(1): 55-66.
22. Pons M et al. Sodium Hyalorunate in the treatment of hallux Rigidus. A single-blinded, randomised study. Foot Ankle Int. 2007; 24:332-42
23. Grady JF et al. A retrospective analysis of 772 patients, with hallux Limitus. JAPMA 2002; 92: 102-8.
24. Dutra T. Inside insights on Orthotic Modifications for Sports. Podiatry Today 17(10) October 2004.
25. Mann RA, Clanton TO. Hallux Rigidus : treatment by cheilectomy. J Bone and Joint Surg. 1988; 70A: 400-6
26. Heller WA et al. The effects of cheilectomy on dorsiflexion of the first metatarsophalangeal joint. FAI 1997;18: 803-8
27. Nowoczensk
28. Blyth MJG et al. Dorsal wedge osteotomy in treatment of Hallux Rigidus. J Foot Ankle Surg 1998; 37:8-10.
29. Gonzalez JV et al. The modified Hohmann osteotomy: an alternative joint salvage procedure for hallux Rigidus. JFAS 2004; 43:380-8.
30. Kelikian AS. Technical considerations in Hallux metatarsophalangeal arthrodesis. Foot Ankle Clin 2005; 10: 167-90.
31. Chana GS, Andrew TA, Cotterill CP. A Simple method of arthrodesis of the first metatarsophalangeal joint. J Bone Joint Surg Br 1984; 66: 703-5
32. O’Doherty DP, Lowrie IG, Magnussen PA et al. The management of the painful first metatarsophalangeal joint in the older patient: arthrodesis or Keller’s arthroplasty? J Bone Joint Surg Br 1990; 72(5): 839-42.
33. Rongstad DJ, Miller GJ, Vadergriend RA et al. A biomechanical comparison of four fixation methods, of the first metatarsophalangeal joint arthrodesis. Foot Ankle Int. 1994; 15: 415-9.
34. Watson AD, Kelkian AS. Cost-effectiveness comparison of three methods of internal fixation for arthrodesis of the first metatarsophalangeal joint. Foot Ankle Int. 1998; 19:304-10.
35. Politi Jet al. First meatatarsophalangeal joint arthrodesis: a biomechanical assessment of stability. FAI 2003; 24:332-7.
36. Curtis MJ, Myerson M, Jinnah RH et al. Arthrodesis of the first metatarsophalangeal joint: a biomechanical study of internal fixation techniques. Foot Ankle Int. 1993; 14:395-9.
37. Hamilton WG et al. Capsular interposition arthroplasty for severe hallux Rigidus. Foot Ankle 1997; 18: 68-70.
38. Swanson AB, Lumbsden RM, Swanson GD. Silicon implant arthroplasty of the great toe. Clin orthop 1979; 142: 30.
39. Fuhrman RA, Wagner A, Anders JO. First metatarsophalangeal joint replacement: the method of choicefor end-stage hallux Rigidus? Foot Ankle Clin. 2003 Dec; 8(4) 711-21,vi.
40. Kulshreshtha et al
41. Jan-Eric Esway et al. Joint Replacement in hallux metatarsophalangeal joint: Foot Ankle Clin N Am; 10 (2005) 97-115.
42. Townley CO, Taranow WS. A metallic hemi-arthroplasty resurfacing prosthesisfor the hallux metatarsophalangeal joint. Foot Ankle Int. 1994; 15(11):552-63.
