Replacement arthroplasty for hallux rigidus. 21 patients with a 2-year follow-up

A prospective clinical and biomechanical analysis of feet following first metatarsophalangeal joint replacement

BACKGROUND

There is a lack of research providing a biomechanical outcome following 1^st MTPJ replacement for hallux rigidus. Despite this, 1^st MTPJ replacement continues to be an alternative surgical option to fusion for this painful debilitating condition. Several studies do consider the patient reported outcomes which are subjective.

RESEARCH QUESTION

The objective of this study is to provide an in depth biomechanical analysis to examine the effects of 1^st MTPJ replacement for hallux rigidus on gait mechanics.

METHODS

Kinematic data was collected at our CMAS (Clinical Movement Analysis Society) UK accredited gait laboratory during the gait cycle together with pressure plate pressure readings and a validated patient outcome measure before surgery and at 6 and 12 months after surgery. A complete literature review is performed.

RESULTS

Kinematic data revealed a significant increase in stride length, cadence and velocity following 1^st MTPJ replacement for hallux rigidus. Foot kinematic data revealed significantly reduced tibia-hindfoot abduction and pronation and reduced hindfoot-forefoot supination and adduction. There was no effect on 1^st MTPJ weight bearing range of motion. Pressure plate data revealed an increase in peak pressure and pressure time integral towards the 1^st metatarsal following surgery. There was a significant improvement in the patient reported outcome measure.

SIGNIFICANCE

This study has demonstrated objectively that following 1^st MTPJ replacement, biomechanically, a restoration of the foot posture to allow medialisation of foot pressures towards the medial column and normalisation of gait including an increase in the stride length, cadence and velocity and that clinically, there was an improvement in the MOXFQ.

Total Arthroplasty of the Metatarsophalangeal Joint of the Hallux

BACKGROUND

The current gold standard in the treatment of severe hallux rigidus is arthrodesis of the first metatarsophalangeal (MTP-I) joint. We present the results of a new 3-component MTP-I prosthesis. We determined (1) the intraoperative and perioperative complications; (2) survivorship of prosthesis components and rate of secondary surgeries for any reason; (3) prosthetic component stability and radiographic alignment; (4) the degree of pain relief; and (5) the midterm functional outcomes including radiographic range of motion (ROM).

METHODS

From 2008 to 2010, we prospectively included 29 MTP-I prostheses in 25 patients. The average age of the patients was 63.1 years (range, 48-87 years). The average follow-up was 49.5 months (range, 36-62 months). We observed complications and reoperations. A visual analog scale for pain and the American Orthopaedic Foot & Ankle Society (AOFAS) forefoot score were obtained pre- and postoperation. Component stability and alignment were assessed using weight-bearing radiographs. Fluoroscopy was used to determine radiographic MTP-I ROM.

RESULTS

Seven (24.1%) patients underwent 1 or more secondary surgeries. Four cases (13.7%) eventually had a conversion to MTP-I arthrodesis. Two patients (3 cases) died from causes not related to the procedure. This left 22 feet in 19 patients for final follow-up. All but 3 remaining prostheses showed stable osteointegration and no migration, but MTP-I alignment showed high variability. The average pain score decreased from 5.9 (range, 3-9) to 1.2 (range, 0-5). The average AOFAS forefoot score increased from 55 (range, 0-80) to 83.5 (range, 58-95). Range of motion initially increased from 37.8 degrees (range, 0-60 degrees) to 88.6 degrees (range, 45-125 degrees) intraoperatively and decreased to 29.0 degrees (range, 11-52 degrees) at latest follow-up.

CONCLUSION

Our data suggest that total arthroplasty of MTP-I leads to a high amount of revision surgeries, but the remaining patients had significant pain relief at midterm follow-up. However, we observed high variability regarding the prosthesis component alignment and poor range of motion.

LEVEL OF EVIDENCE

Level IV, prospective cohort study.

Total Toe Replacement in the United States: What Is Known and What Is on the Horizon

Arthritis of the first metatarsophalangeal is a common problem of the forefoot. The gold standard surgical treatment has been fusion of the first metatarsophalangeal joint. Many patients are unwilling to accept pain relief at the expense of loss of motion and the corresponding loss of shoe wear choices and activities requiring dorsiflexion of the hallux. Early implants were plagued with loosening and continued pain but implants have evolved. Current implants use modern bearing surfaces with press-fit fixation. These implants have renewed optimism for total toe arthroplasty. This article reviews the literature for implants currently available and describes the surgical techniques.

Pain after cheilectomy of the first metatarsophalangeal joint: diagnosis and management

Cheilectomy is commonly performed for osteoarthritis of the first metatarsophalangeal joint and generally has a successful outcome and high rate of patient satisfaction over the short to medium term. Despite the relatively good results achieved in most cases, a proportion of patients have ongoing pain after cheilectomy. This article outlines the potential causes of ongoing pain, including progression of osteoarthritis, neuralgic symptoms, and transfer metatarsalgia. Management strategies for treating the ongoing symptoms are discussed.

Implants for the first metatarsophalangeal joint and prospective considerations

This article reviews the anatomy, pathology and biomechanics of the key joint of the foot, the first metatarsophalangeal joint, before focusing on the various designs of prosthesis that have been proposed for this joint. Metal hemiarthroplasties, single-piece, double-stem silicone implants and multicomponent implants are all considered in detail, as is an assessment of the available clinical results. In addition, preimplantation testing of the implants and the value of explant studies are discussed.

Short-term functional outcomes of first metatarsophalangeal total joint replacement for hallux rigidus

BACKGROUND

Although metatarsophalangeal (MTP) arthrodesis has been advocated by many authors, implant arthroplasty appears to be successful option in advanced hallux rigidus (HR). The aim of our study was to evaluate the early results of the ToeFit-Plus prosthesis for the treatment of HR.

METHODS

Between December 2007 and January 2011, a total of 26 toes of 24 patients with MTP arthritis of the great toe were treated with ToeFit-Plus implant. The average follow-up time was 29.9 (range: 25 to 62) months. All patients were evaluated clinically and radiographically. Postoperative satisfaction and function were scored according to the American Orthopaedic Foot and Ankle Society (AOFAS) score. Pain was assessed with the use of a visual analogue scale.

RESULTS

Mean preoperative AOFAS score improved from 42.7 (range: 36 to 59) to 88.5 (range: 59 to 98) at the final follow-up (P < .01). Preoperative average visual analogue scale pain scores improved from 7.4 preoperatively to 1.9 at the final follow-up (P < .01). The average MTP joint range of motion improved from 25.9 degrees preoperatively to 53.8 degrees at the final follow-up. No radiologic loosening was found, but radiolucency was observed in 2 patients with this implant. No revision was required for any of the patients during the follow-up period.

CONCLUSIONS

This total first MTP joint prosthesis yielded good functional outcome and high patient satisfaction level with low early complication rate. Preservation of joint movement and good pain relief with early mobilization were the advantages of this procedure. Salvage arthrodesis remains an option if future revisions are indicated.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Design of an implant for first metatarsophalangeal hemi-arthroplasty

This study was designed to examine the three-dimensional geometry of the head of the first metatarsal bone of the foot. Ninety-seven adult first metatarsal head (MTH1) bones were scanned using a laser scanner at 400 dpi. A best-fit ellipsoid was obtained from the articular surfaces of MTH1 for each size group using nonlinear unconstrained optimisation. Average root mean square errors between the articulating surfaces and the optimal fit surfaces of the bone specimens were between 0.29 and 0.42 mm. After classification based on sex and size groups, the profile provided a good fit to individual bones. Consideration of the thickness of cartilage overlying the metatarsal head (MTH) may further improve the fit. The proposed approach provides the basis for a design of an MTH hemi-arthroplasty that has good anatomical congruence with the native joint.

Prospective analysis of a first MTP total joint replacement. Evaluation by bone mineral densitometry, pedobarography, and visual analogue score for pain

BACKGROUND

We hypothesized that a total replacement of the first metatarsophalangeal joint (MTP-1) would alter the walking pattern with medialisation of the ground reaction force (GRF) of the foot and subsequently cause an increase in bone mineral density (BMD) in the medial metatarsal bones and a decline of BMD in the lateral metatarsal bones.

METHODS

Twelve patients receiving total joint replacements (Roto-Glide(®)) of MTP-1 were enrolled in a prospective cohort. BMD and pedobarography of the heel bone and the metatarsal heads were performed preoperatively and at least 12 months postoperatively.

RESULTS

BMD in the lateral metatarsals and GRF under the lateral column of the operated feet decreased significantly on the operated feet.

CONCLUSIONS

Total joint replacement of MTP-1 tends to reduce GRF under the lateral column of the foot causing a corresponding decline in BMD and pedobarographic measures. Our findings support the further use of the Roto-Glide(®) prosthesis for osteoarthritis of the first metatarsophalangeal joint.

Quantitative review of operative management of hallux rigidus

INTRODUCTION

Surgical techniques for the management of hallux rigidus include cheilectomy, Keller resection arthroplasty, arthrodesis, Silastic implantation, phalangeal or metatarsal osteotomy, capsular arthroplasty, partial or total joint replacement, interposition arthroplasty. However, the optimal management is controversial.

SOURCES OF DATA

We performed a comprehensive search of CINAHL, Embase, Medline and the Cochrane Central Registry of Controlled Trials, from inception of the database to 2 November 2010. Sixty-nine articles published in peer reviewed journals were included in this comprehensive review.

AREAS OF AGREEMENT

Cheilectomy and first metatarsal or phalangeal corrective osteotomy may provide better outcome for patients with early and intermediate hallux rigidus (Stages I-II), while arthrodesis or arthroplasty are indicated to manage more severe conditions. The Coleman Methodology Score showed great heterogeneity in terms of study design, patient characteristics, management methods and outcome assessment and generally low methodological quality.

AREAS OF CONTROVERSY

Definitive conclusions on the use of these techniques for routine management of patients with hallux rigidus are not possible. Given the limitations of the published literature, especially the extensive clinical heterogeneity, it is not possible to compare outcomes of patients undergoing different surgical procedures and determine clear guidelines.

GROWING POINTS

To assess whether benefits from surgery, validated and standardized measures should be used to compare the outcomes of patients undergoing standard surgical procedures.

RESEARCH

There is a need to perform appropriately powered randomized clinical trials of using standard diagnostic assessment, common and validated scoring system comparing reported outcomes and duration of follow-up >2 years.

First metatarsophalangeal hemiarthroplasty for hallux rigidus

There is a paucity of objective information in the literature about first metatarsophalangeal (MTP) hemiarthroplasty. The authors postulate that it is a reasonable treatment option for severe hallux rigidus in selected patients. Twenty-two elective first MTP hemiarthroplasties were performed on 20 patients that met the inclusion criteria. Pre- and postoperative evaluations were done using the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score, visual analogue scale (VAS) pain score, range of motion (ROM) measurements, and radiographs. Average ROM and dorsiflexion improved by 15° and 8°, respectively. VAS pain scores improved from 5 to 2.5 after six weeks. Painless ambulation occurred after six weeks, with maximum improvement by six months. After 24 months, two patients had pain at the surgical site interfering with function, leading to an unsatisfactory result that required conversion to arthrodesis. First MTP hemiarthroplasty for severe hallux rigidus can be considered an alternative to fusion in properly selected patients who wish to maintain a functional range of motion.

Survivorship of the bio-action metatarsophalangeal joint arthroplasty for hallux rigidus: 5-year follow-up

BACKGROUND

Metatarsophalangeal joint arthroplasty is an accepted treatment for hallux rigidus. There are few reports of the long-term results of this procedure.

METHODS

A series of 15 consecutive bio-action first metatarsophalangeal total joint replacements were retrospectively reviewed after a minimum follow-up of 5 years. The patients were assessed using the American Orthopaedic Foot and Ankle Society Score. Patient satisfaction and standard radiographs were also examined.

RESULTS

Subjectively, just over half the patients were satisfied with the results of the surgery. Objectively, however mechanical failure of the implant was universal, as determined radiographically.

DISCUSSION

Despite some success in relieving symptoms in patients, we have abandoned this procedure because of the high and increasing rate of failure, as demonstrated both clinically and radiologically.

Recreational sport activity after total replacement of the first metatarsophalangeal joint: a prospective study

First metatarsophalangeal joint replacement is an alternative surgical procedure to arthrodesis in the treatment of moderate-to-severe hallux rigidus. However, few studies have been published about functional outcome after joint reconstructive procedures for hallux rigidus. The purpose of this study was to assess clinical, radiological and functional outcome, with special regard to recreational and sports activity, after first metatarsophalangeal joint replacement in patients affected by hallux rigidus grade III. Twenty-three patients who had undergone total joint replacement of the first metatarsophalangeal joint were examined preoperatively and three, six, 12 and 18 months postoperatively. All patients (mean age of 57.0 ± 3.7 years) received a non-cemented TOEFIT-PLUS™ implant by one surgeon. Clinical scores (AOFAS score and VAS), radiological examination, patient satisfaction and sport participation were used to evaluate treatment outcome and radiolucent lines. The mean AOFAS score showed a significant improvement from 44.6 ± 7.2 points preoperatively to an average of 82.5 ± 14.4 points at last follow-up (p < 0.001). The mean total ROM of the first MTP joint increased from 28.1 ± 4.9 degrees preoperatively to 52.7 ± 15.7 degrees postoperatively (p < 0.001). After surgery, 91.3% of the patients were able to resume at least one recreational activity. Total arthroplasty for the treatment of hallux rigidus in an active patient population revealed good clinical and functional results. However, postoperative recreational sport activity showed a decrease in comparison to the pre-arthritic state. Further follow-up is necessary to quantify loosening risk in active patients after total hallux arthroplasty.

The Valenti technique in the treatment of hallux rigidus

INTRODUCTION

Metatarsophalangeal joint osteoarthritis of the great toe (hallux rigidus) is a frequent condition for which numerous surgical techniques have been proposed. The most used ones are cheilectomy and arthrodesis. The objectives of this retrospective study are to present the midterm results of the Valenti procedure and to compare these results with those from other recognized surgical techniques.

MATERIALS AND METHODS

We conducted a retrospective analysis of a continuous group of 32 patients (41 cases) presenting hallux rigidus and treated using the Valenti technique from November 1999 to July 2004. The mean age of these patients at the time of surgery was 57 years. Forty-one percent of these patients also presented a static disorder of the foot. One or several additional procedures were undertaken, at the time of surgery, in 24% of these cases. Patients were assessed using the AOFAS score completed by the walking distance test, the gait test, the tiptoe test and self-evaluation of patient satisfaction. The radiographic work-up before surgery and at follow-up showed the progression of the joint space changes and allowed us to evaluate plantar subluxation at the base of the first phalanx under the metatarsal head.

RESULTS

Twenty-four patients (32 cases) were reviewed and evaluated with a mean follow-up of 5.5 years. Two cases of reflex sympathetic dystrophy were observed as complications. The mean final score was 81 out of 100 from a preoperative score of 47 out of 100. Pain was absent or only occasional in 94% of the cases. Discomfort wearing shoes was absent or moderate in 91% of the cases. Joint range of movement was greater than 30 degrees in 72% of the cases and the toes were stable. Walking distance was unlimited in 79% of the cases. A mean 30% plantar subluxation at the base of the first phalanx was noted at follow-up, with no clinical consequence. The results were comparable irrelevantly of the hallux rigidus grade being treated.

DISCUSSION

The numerous techniques proposed achieve comparable results both in terms of pain relief and functional result but each one has its own limitations. Only arthroplasties with silastic implants and the Keller technique give less satisfactory results. Arthrodesis remains the first-choice treatment for advanced hallux rigidus but failure is possible in case of technical error or malunion. Cheilectomy, a conservative intervention, is ideal for lesions that are not too advanced or remain limited to the dorsal part of the joint; this conservative option presents generally no specific complications. Prosthetic replacement--with, to date, little long-term experience for total arthroplasty--remains controversial because the results deteriorate over time. The Valenti procedure exposes the patient to a possible risk of metatarsophalangeal joint destabilization if the resection is too great, but this does not impair the final functional outcome.

CONCLUSION

The arthrectomy described by Valenti is a highly reproducible intervention. We find it to be a good compromise between mobility and stability, providing good results for all hallux rigidus grades and entailing a low complication rate.

LEVEL OF CLINICAL EVIDENCE

Level IV. Therapeutic Study.

Meta-analysis of first metatarsophalangeal joint implant arthroplasty

Management of late-stage degenerative joint disease of the first metatarsophalangeal joint (MPJ) is a complex topic that is frequently the source of debate among foot and ankle surgeons. Several surgical interventions have been described to treat this condition. One of the most contested of these treatments is implant arthroplasty of the first MPJ. The primary aim of this meta-analysis was to evaluate the clinical benefit of first MPJ implant arthroplasty in regard to patient satisfaction. Reviewers formally trained in meta-analysis abstraction techniques searched databases and indices using medical subject heading terms and other methods to identify all relevant studies published since 1990. Initially, 3874 citations were identified and evaluated for relevance. Abstract screening produced 112 articles to be read in entirety, of which 47 articles studying 3049 procedures with a mean 61.48 (SD 45.03) month follow-up met all prospective inclusion criteria necessary for analysis. Overall crude patient satisfaction following first MPJ implant arthroplasty was 85.7% (95% confidence interval: 82.5%-88.3%). When adjusting for lower quality studies (retrospective, less than 5 years of follow-up, higher percent of patients lost to follow-up), the overall patient satisfaction increased to 94.5% (89.6%-97.2%) in the highest-quality studies. This adjustment also significantly decreased heterogeneity across studies (crude Q = 184.6, high-quality studies Q = 2.053). Additional a priori sources of heterogeneity were evaluated by subgroup analysis and meta-regression. In regards to patient satisfaction, this comprehensive analysis provides supportive evidence to the clinical benefit of first MPJ implant arthroplasties.

LEVEL OF CLINICAL EVIDENCE

1.

A finite-element analysis study of the metatarsophalangeal joint of the hallux rigidus

Hallux rigidus was first described in 1887. Many aetiological factors have been postulated, but none has been supported by scientific evidence. We have examined the static and dynamic imbalances in the first metatarsophalangeal joint which we postulated could be the cause of this condition. We performed a finite-element analysis study on a male subject and calculated a mathematical model of the joint when subjected to both normal and abnormal physiological loads.

The results gave statistically significant evidence for an increase in tension of the plantar fascia as the cause of abnormal stress on the articular cartilage rather than mismatch of the articular surfaces or subclinical muscle contractures. Our study indicated a clinical potential cause of hallux rigidus and challenged the many aetiological theories. It could influence the choice of surgical procedure for the treatment of early grades of hallux rigidus.

[Results for endoprosthetic care in patients younger than 50 years]

Arthroplasty has become the most successful surgical procedure in developed countries. Replacement of severely damaged joints results in a substantial relief of pain, as the main symptom of osteoarthritis, in the majority of treated patients. With improved results in endoprosthetic surgery over the last decades, however, patients are increasingly undergoing the procedure to enhance their functional capacity and physical mobility. Especially younger patients, who cannot accept a restriction in their professional or sports activity, have become demanding candidates for surgery. This review summarizes the published results on shoulder, hip, knee, ankle and first metatarsophalangeal joint replacement in patients who are younger than 50 years of age. Mid- and long-term follow-up studies in this age group are evaluated in terms of prosthesis survival as well as functional improvement.

The case against first metatarsal phalangeal joint implant arthroplasty

This article argues the practice of first metatarsal phalangeal joint (MPJ) implant arthroplasty. Intermediate and long-term studies raise concerns about implant failure and longevity. Other causes for concern are silicone-induced synovitis and lymphadenopathy. This article presents evidence against the practice of first metatarsal phalangeal implant arthroplasty. Intermediate and long-term studies raise concerns about implant failure and longevity. Furthermore, the lack of any significant long-term results and the documented metallic breakdown from two-piece metallic implants make their use in hallux rigidus questionable. Meanwhile, a comparative study shows the superiority of arthrodesis to implant arthroplasty. Also, alternatives to joint-destructive procedures are emerging. These include arthrodiastasis and the osteochondral autograft transfer procedure. This evidence proves that implant arthroplasty is not the best treatment for patients with hallux rigidus or other first-MPJ pathology.

Analyse opto-électronique de la marche après arthrodèse métatarso-phalangienne de l’hallux

PURPOSE OF THE STUDY

Degeneration of the metatarsophalangeal joint of the hallux is a frequent secondary lesion of the first ray subsequent to hallux valgus. Different surgical techniques have been proposed for cure, including metatarsophalangeal arthrodesis. Joint fusion relieves pain but sacrifices joint motion. The purpose of this work was to assess changes observed in gait after metatarsophalangeal arthrodesis of the hallux using a three-dimensional optoelectronic system.

MATERIAL AND METHODS

Gait analysis was performed with a Vicon 3D system with five cameras and two AMTI force platforms in twelve patients who had undergone metatarsophalangeal arthrodesis more than six months earlier. The kinetic and kinematic curves and ground reaction forces were analyzed. Changes in the gait cycle and any compensations observed in the talocrural and interphalangeal joints were noted in the three dimensions. Wilcoxon test for paired series was applied for the statistical analysis.

RESULTS

The general gait parameters and kinetic and kinematic values were not modified (excepting a non-significant decline in maximal dorsiflexion of the ankle joint). There was a significant decrease in propulsion force in the anteroposterior and vertical planes, with significantly later heal lift-off and systematic displacement of ground reaction forces anterior to the metatarsophalangeal joint on the arthrodesis side. Reflectors positioned on the distal extremity of the hallux demonstrated that the essential part of compensation occurred at the level of the interphalangeal joint.

DISCUSSION

Gait analysis after tibiotalar arthrodesis has been widely reported in the literature. The consequence of joint fusion on the rear foot and/or the torsion couple have also been studied. However, to our knowledge, there has been only one report using a different methodology devoted to metatarsophalaneal arthrodesis of the hallux. In this study, only step length and interphalangeal moment as well as ankle force were found to be decreased. Function of the interphalangeal joint was not assessed. The Vicon system enabled an adapted study of gait after metatarsophalangeal arthrodesis. This method offers several perspectives: study of the effect of the position of the arthrodesis in the sagittal plane on gait, changes over time in interphalangeal joint motion, or consequences of fusion on walking up and down stairs.

CONCLUSION

Metatarsophalangeal arthrodesis of the hallux does not modify general gait parameters nor the kinetic and kinematic values. Compensation is achieved via the interphalangeal joint.

First metatarsophalangeal joint replacement using the bio-action great toe implant: intermediate results

BACKGROUND

With improvements in biomaterials and design, implant arthroplasty is becoming a useful option for treatment of disorders of the hallux.

METHODS

Forty-eight patients (53 implants) who had Bio-Action great toe implants (Osteomed, Addison, TX) for symptomatic advanced degenerative changes in the first metatarsophalangeal (MTP) joint have been followed prospectively since August of 1998. We reviewed the functional results of 32 patients (36 implants) at a minimum followup of 36 (range 36 to 69, mean 47) months. The scoring system designed by Kitaoka etal. was used to assess the functional results. Patient satisfaction, length of hospital stay, time to return to routine activities, footwear problems, radiographic appearances, and complications also were studied.

RESULTS

With the numbers available, there was significant improvement in the range of motion achieved and hallux MTP scale after the operation. There was a positive correlation (r = 0.87) between patient satisfaction and the hallux MTP scale. However, there was no correlation between patient age and patient satisfaction or hallux MTP scale. Seventy-seven percent of patients considered the result of the operation to be good or excellent.

CONCLUSION

Overall, the 5-year functional results of this total joint system appeared to be satisfactory.

Contemporary approaches to stage II and III hallux rigidus: the role of metallic hemiarthroplasty of the proximal phalanx

Metallic proximal phalangeal hemiarthroplasty has been described for the surgical treatment of moderate to severe hallux rigidus. This long-term follow-up of an extended case series of 37 patients who underwent the index operation demonstrated a high rate (93%) of patient satisfaction, and significant improvement in Foot Function Index scores.

Arthrodesis or total replacement arthroplasty for hallux rigidus: a randomized controlled trial

BACKGROUND

Arthrodesis is the current treatment for end-stage hallux rigidus, although there are many reports advocating total joint replacement arthroplasty. The aim of this randomized controlled trial was to evaluate clinical outcomes after first metatarsophalangeal joint (MTPJ) arthrodesis and replacement arthroplasty.

METHODS

Between November, 1998, and January 2001, 63 patients between the ages of 34 and 77 years, with unilateral or bilateral MTPJ arthritis were recruited and randomly selected to have either MTPJ arthrodesis or arthroplasty. Twenty-two patients (38 toes) had arthrodesis and 27 patients (39 toes) had arthroplasty. A single surgeon performed all surgery. The primary outcome measure determining successful surgery was a decrease in pain as measured on a Visual Analogue Scale (VAS). Functional outcome was assessed at 6 months and 1 and 2 years. Cost data were simultaneously collected.

RESULTS

At 24 months, pain improved in both groups (p < 0.001), but there were significantly greater improvements after arthrodesis (p = 0.01). All 38 arthrodeses united at a mean dorsiflexion angle of 26 degrees, with few complications. In contrast, in the arthroplasty group, six of the 39 inserted implants had to be removed because of phalangeal component loosening. In the remainder the range of motion gained was poor, and the patients tended to bear weight on the outer border of their foot. The cost ratio was 2:1 in favor of arthrodesis.

CONCLUSIONS

Outcomes after arthrodesis were better than those after arthroplasty. The results were partially attributable to an unacceptably high incidence of loosening of the phalangeal components, which resulted in removal of the implants. However, even when data from the failures were excluded, arthrodesis was clearly preferred by most patients.

Joint replacement in the hallux metatarsophalangeal joint

Joint replacement of the hallux metatarsophalangeal joint has not enjoyed the same success as hip and knee arthroplasties. Silastic implants have achieved a high patient satisfactory rate but have caused many complications, including silicone synovitis and lymph node inflammation. Metal and polyethylene hemiarthroplasties and total toe replacements seem to be more promising although results are preliminary. Problems with these implants seem to be related to soft tissue instability of the joint; patients who have hallux rigidus have more success than patients who have hallux valgus or rheumatoid arthritis. Severe complications can be treated with removal and synovectomy or arthrodesis, depending on the length and alignment of the foot, as well as the functional demands of the patients. It would be beneficial to have more data on these implants so that improvements can be made in design and patient selection.

First metatarsophalangeal joint replacement: the method of choice for end-stage hallux rigidus?

Replacement of the first metatarsophalangeal (MTP) joint remains critical because of complex biomechanical conditions and implant fixation. After a 3-year follow-up, most patients who experienced an MTP joint replacement were extremely satisfied with the outcome. Plantar pressure distribution revealed a marked improvement. Nevertheless, recovery of MTP dorsiflexion was limited and joint stability worsened. Radiologically, one-third of the prostheses showed radiolucent lines as a sign of implant loosening. MTP replacement offers distinct advantages in the treatment of end-stage hallux rigidus, but requires further research on implant design and osseous fixation.

Arthrodesis in the treatment of hallux rigidus

We reviewed 34 patients (38 joints) with hallux rigidus treated from 1989 to 1999 with arthrodesis of the first metatarsophalangeal joint. Average patient age at time of surgery was 52 (24-71) years, and the mean follow-up was 54 (18-116) months. There were six superficial infections, and all arthrodeses united. There was a good functional result with a significant pain reduction. The mean postoperative American Orthopaedic Foot and Ankle Society (AOFAS) score was 53 (5-84) points.