Prospective, Randomized, Multi-centered Clinical Trial Assessing Safety and Efficacy of a Synthetic Cartilage Implant Versus First Metatarsophalangeal Arthrodesis in Advanced Hallux Rigidus

Midterm functional outcomes of synthetic cartilage implant (SCI) arthroplasty for hallux rigidus

Hallux rigidus is a common degenerative condition of first metatarso-phalangeal joint most commonly affecting patients above 50 years of age. The aim of our study is to evaluate the five-year results of synthetic cartilage implant (Cartiva) arthroplasty for hallux rigidus. A retrospective study of 70 patients who underwent synthetic cartilage implant interpositional arthroplasty were collected and analysed. Patients with Grade 3 to 4 hallux rigidus and who had failed conservative management were included. Patients who had previous forefoot surgery, hallux varus or valgus deformity of more than 250 and neuromuscular disease were excluded. Mean age at the time of operation was 63.4 years (range 42-84 years). The mean follow-up was 62.6 months. The functional evaluation was done using Manchester-Oxford Foot Questionnaire (MOxFQ). EQ-5D and EQVAS. 86 patients were matriculated in the study with 70 patients being assessed at five years. The average preoperative MOxFQ score improved from 35.74 (31.44-40.04) to 19.11 (11.31- 26.91) at one year after surgery. The EQ-5D scores improved from preoperative average of 9.40 (8.14-10.66) to 4.26 (2.09-6.43) at one year. The preoperative EQVAS was 61.66 (51.25-72.07) to 71.45 (60.87-82.03 at one year. At five years follow up the average MOxFQ score was 17.6 (9.92-24.38), EQ-5D - 4.8 (2.26- 6.45) and EQVAS - 72.48 (62.40-82.56). Three patients had revision to first MTP fusion due to ongoing pain. Synthetic cartilage implant has demonstrated clinical efficacy and good functional outcomes at the end of five years for the treatment of Hallux rigidus. Level of Clinical Evidence: 4.

Cartiva interpositional arthroplasty versus arthrodesis in the treatment of Hallux rigidus: A retrospective comparative study with mean 2 year follow up

BACKGROUND

Hallux rigidus is a common condition characterised by first metatarsophalangeal joint (MTPJ) degeneration, pain and limited range of motion (ROM). The gold standard surgical treatment is arthrodesis, providing good pain relief, but sacrifices ROM. The Cartiva synthetic cartilage implant (SCI) has been utilised as an interpositional arthroplasty, aiming to reduce pain whilst preserving range of motion. Current evidence for Cartiva SCI is limited. The aim was to evaluate the clinical outcomes of Cartiva SCI compared to arthrodesis undertaken in our centre.

METHODS

A retrospective cohort study was conducted, enrolling all adult patients who underwent primary first MTPJ SCI arthroplasty or arthrodesis for the treatment hallux rigidus. The primary outcome was a validated patient-reported outcome measure (PROM), the Manchester-Oxford Foot Questionnaire (MOXFQ). Secondary outcomes included EQ-5D, complication rates, VAS Pain and FAAM (ADL).

RESULTS

Between 2017 and 2020 there were 33 cases divided into two groups (17 Cartiva SCI, 16 arthrodesis, mean age 59.0 ± 9.9 years) with a mean follow up of 2.3 years. There was no statistically significant difference in any of the MOXFQ, EQ-5D, VAS Pain or FAAM (ADL) outcome scores between the Arthrodesis and SCI groups (p > 0.05). The mean MOXFQ Index score was 7.2 ± 6.4 for the SCI group and 3.9 ± 5.8 for the Arthrodesis group at final follow up (p = 0.15). Although complications were high in both groups, the overall hallux reoperation rate was 29.4 % in the SCI cohort and 0.0 % for arthrodesis.

CONCLUSION

This retrospective comparative study found no significant superiority of Cartiva SCI over arthrodesis in terms of PROMs. Due to the higher rate of further surgical intervention in the SCI cohort, we recommend arthrodesis as the preferred surgical option for hallux rigidus.

LEVEL OF EVIDENCE

III.

Mid-term efficacy of the Cartiva synthetic cartilage implant in symptomatic hallux rigidus

Aims

The Cartiva synthetic cartilage implant (SCI) entered mainstream use in the management of first metatarsophalangeal joint (MTPJ) arthritis following the positive results of large trials in 2016. Limited information is available on the longer-term outcomes of this implant within the literature, particularly when independent from the originator. This single-centre cohort study investigates the efficacy of the Cartiva SCI at up to five years.

Methods

First MTPJ arthritis was radiologically graded according to the Hattrup and Johnson (HJ) classification. Preoperative and sequential postoperative patient-reported outcome measures (PROMs) were evaluated using the Manchester-Oxford Foot Questionnaire (MOXFQ), and the activities of daily living (ADL) sub-section of the Foot and Ankle Ability Measure (FAAM).

Results

Patients were followed up for a mean of 66 months (SD 7.1). Of an initial 66 cases, 16 did not return PROM questionnaires. A total of six failures were noted, with survival of 82%. Overall, significant improvement in both objective scores (MOXFQ and FAAM ADL) was maintained versus preoperatively: 18.2 versus 58.0 (p > 0.001) and 86.2 versus 41.1 (p > 0.001), respectively. The improvement was noted to be less pronounced in males. Subjective scores had deteriorated since early follow-up, with an interval decrease in patient satisfaction from 89% to 68%. Furthermore, a subset of cases demonstrated clinically important interval deterioration in objective scores. However, no specific patient factors were found to be associated with outcomes following analysis.

Conclusion

This study represents the longest-term independent follow-up in the literature. It shows reassuring mid-term efficacy of the Cartiva SCI with better-than-expected survival. However, deterioration in scores for a subset of patients and lower satisfaction may predict ongoing failure in this group of patients. Additionally, males were noted to have a lower degree of improvement in scores than females. As such, ongoing observation of the SCI to assess durability and survivability, and identify predictive factors, is key to improving patient selection.

Synthetic cartilage implant vs. first metatarsophalangeal arthrodesis for the treatment of hallux rigidus

BACKGROUND

This study evaluated the outcome of the Cartiva synthetic cartilage implant (SCI) in the treatment of hallux rigidus.

METHODS

In the present retrospective matched case-control study, we compared 18 patients with Cartiva SCI (mean follow-up: 17.7 months) to 18 patients with metatarsophalangeal joint arthrodesis (mean follow-up: 20 months) using multiple function measures, along with four specified visual analog subscales for pain. Pre- and postoperative radiographs were compared, and radiographic abnormalities were documented.

RESULTS

We observed no significant differences in function measures between groups. While both groups experienced significant pain reduction, the arthrodesis group reported significantly lower exertion pain than the Cartiva SCI group (p = 0.004). Radiographic abnormalities, including implant site enlargement (6/18, 33.3%), erosive changes of the metatarsal bone (11/18, 61.1%) or articular surfaces (10/18, 55.6%), and bright sclerotic margins (12/18, 66.7%), occurred in the Cartiva SCI group.

CONCLUSION

The present study showed good functional results and a high satisfaction rate after MTP joint arthrodesis, which is considered the gold standard surgical treatment for higher grade hallux rigidus. While the Cartiva SCI group did not show significant differences from the arthrodesis in most aspects of function and clinical scores, the arthrodesis group tended to have better results in terms of satisfaction, residual pain, and revision rate. Even after the short follow-up period, there were some remarkable radiographic findings in the Cartiva SCI group, the long-term effects of which are not yet evident, but which may lead to implant loss. Cartiva SCI has advantages for patients who prioritize postoperative mobility, but the potential risks should be considered in the patient's informed consent. Therefore, the present study highlights the importance of MTP joint arthrodesis for the treatment of hallux rigidus.

LEVEL OF EVIDENCE

Level IV - Retrospective matched case-control study.

Surgical Management of Failed First Metatarsophalangeal Joint Arthroplasty

This article describes the etiology, clinical presentation, surgical management, and outcomes for treatment of the failed first metatarsophalangeal (MTP) joint arthroplasty. Failure following implant arthroplasty typically creates large osseous deficits and surgical management can be difficult. Salvage arthrodesis provides reliable joint stability while maintaining hallux length. Outcomes following conversion of a failed MTP joint arthroplasty to MTP joint arthrodesis have demonstrated consistent pain relief and high satisfaction: however, high rates of complication and nonunion have been reported. Bone graft may be necessary to fill large voids in the joint. Other revision options for failed arthroplasty have been described, but outcomes remain inconsistent and varied. Ultimately, conversion to MTP joint arthrodesis is the recommended intervention for treatment of the failed MTP arthroplasty implant, providing sufficient stability and pain relief.

Managing Hallux Rigidus in the Elite Athlete

Hallux rigidus can present a difficult problem to both competitive and elite athletic populations. Once an appropriate diagnostic workup has been performed, nonoperative management strategies, including anti-inflammatory medications, injection therapies, shoewear modifications, and orthotic devices, represent the mainstay conservative management options. Surgical management can be considered where an athlete's athletic performance is limited. A joint-sparing cheilectomy can provide a predictable return to sport at the most elite levels. The addition of a proximal phalangeal osteotomy can be considered when necessary. Arthroplasty or arthrodesis techniques can be used for persistent symptoms or progressive disease, but with less predictable outcomes.

The Philosophy of Surgical Success and Outcomes of Cartiva Versus Fusion

Noninferiority studies in surgery are, by their very nature, reductionist. They use multiple variables to generate a yes or no answer about the new device being tested. A binary outcome is appropriate for a regulatory agency such as the Food and Drug Administration, but the clinical situation is more nuanced. It is critical to understand the underlying philosophies and choices that go into trial design when a surgeon is recommending a new device. In the case of Cartiva, any of 3 reasonable alternative means of defining surgical success would have altered the final outcome of the MOTION trial. Additionally, using a more rigorous noninferiority margin rather than adding an additional cushion based upon the argument that motion alone had extra inherent value would have also led to failure of the trial to demonstrate noninferiority.

Quantification of First Metatarsal Joint Surface Interactions in Hallux Rigidus Using Distance and Coverage Mapping: A Case-Control Study

BACKGROUND

Weightbearing cone-beam computed tomography (WBCT) has proven useful for analysis of structural changes of the foot and ankle when compared to conventional radiographs. WBCT allows for extraction of distance and coverage mapping metrics, which may provide novel insight into hallux rigidus (HR). This study retrospectively assessed HR joint space using distance and coverage mapping in a case-control study.

METHODS

WBCT images of the foot and ankle for 20 symptomatic HR and 20 control patients were obtained. Three-dimensional models were created and analyzed using a custom semiautomatic measurement algorithm. Distance and coverage mapping metrics for the first metatarsophalangeal and metatarsosesamoid joints were extracted from the models and compared between cohorts. Relationships between these metrics and visual analog scale (VAS) scores, a patient-reported outcome of pain, were assessed in HR patients.

RESULTS

Overall first metatarsophalangeal joint space narrowing was noted in HR patients when compared to controls by an average of 11.8% (P = .02). However, no significant changes in the overall coverage of the joint were noted. Decreased joint space width and increased surface-to-surface coverage were only and particularly observed at the plantar medial quadrant of the first metatarsal head in HR patients relative to controls. VAS score was significantly but weakly correlated with dorsolateral quadrant coverage (R2 = 0.26, P = .03).

CONCLUSION

Distance and coverage mapping serve as a complementary option to current techniques of quantifying HR changes. These metrics can expand the scope of future work investigating joint articulation changes in HR.

Cartiva: A Review of the Best Evidence

The Cartiva implant is a synthetic polyvinyl alcohol hydrogel cartilage substitute that is used as a treatment of first metatarsophalangeal joint arthritis. The implant was designed to relieve the pain associated with hallux rigidus while preserving or restoring range of motion. A summary of outcomes, reasons for these outcomes, and technique pearls will be reviewed here. Seminal articles and current evidence are all included in this article. The aim is for the surgeon to understand all the literature, allowing the surgeon to counsel their patients appropriately, optimize patient selection and to deal with complications.

Revision Surgery After Failed Index Synthetic Cartilage Implant Resurfacing for Hallux Rigidus: Single-Surgeon 5-Year Experience

BACKGROUND

While metatarsophalangeal joint (MTPJ) arthrodesis is regarded as the gold standard treatment option for end-stage hallux rigidus (HR), synthetic cartilage implant (SCI) resurfacing has gained popularity. This study aimed to identify the SCI resurfacing failure rate for a single surgeon, while also comparing clinical outcomes of patients who underwent SCI replacement or MTPJ arthrodesis after failed index SCI resurfacing.

METHODS

Health records were queried from 2016 to 2021 for patients with HR who were treated with SCI resurfacing by a single surgeon. Preoperative and postoperative range of motion, visual analog scale (VAS) pain scores, and hallux valgus angles were compared. A subgroup analysis was performed on patients who underwent revision with SCI replacement or MTPJ arthrodesis. SCI replacement included the use of bone graft, bone putty, or a custom 3D printed baseplate to prevent implant subsidence.

RESULTS

A total of 219 SCI resurfacing procedures were performed by a single surgeon, including 23 revisions. When analyzing index procedures, an 8.2% revision rate was determined. The revision cohort (n = 23) consisted of 19 female patients and presented with a mean body mass index of 29.5 ± 5 kg/m2, mean age of 52.8 ± 11 years, mean follow-up duration of 22.3 (range, 3-54) months, and mean time to a revision surgery of 12.1 ± 12 (range, 1-50) months. Specifically, 12 procedures resulted in an SCI replacement, while 11 procedures resulted in arthrodesis. While all patients experienced significant improvement in their VAS pain scores (P < .001), the arthrodesis cohort experienced a greater improvement than the SCI revision cohort (P = .04).

CONCLUSION

When analyzing SCI revision procedures, MTPJ arthrodesis reduced pain more significantly than SCI replacement.

LEVELS OF EVIDENCE

Level IV: Retrospective case series.

A Comparison of PROMIS Scores of Metatarsophalangeal Joint Arthrodesis and Polyvinyl Alcohol Hydrogel Implant Hemiarthroplasty for Hallux Rigidus

Background

The current literature shows similar clinical outcomes between first metatarsophalangeal (MTP) joint arthrodesis and synthetic cartilage implant (SCI) hemiarthroplasty in the treatment of hallux rigidus; however, prior studies have not reported validated patient-reported outcome measures (PROMs). To our knowledge, this is the first study to compare PROMs using 6 domains of the validated Patient-Reported Outcomes Measurement Information System (PROMIS) in patients treated for hallux rigidus with MTP joint arthrodesis and with SCI hemiarthroplasty. In addition, this novel study provides comparative data on the complication and revision rates for each procedure.

Methods

A single-center, retrospective registry search identified all patients with preoperative PROMIS scores who underwent MTP joint arthrodesis or SCI hemiarthroplasty for hallux rigidus between February 2016 and June 2021. The study aimed to determine if the 2 procedures showed statistically or clinically equivalent PROMIS scores in 6 domains: physical function, pain interference, pain intensity, global physical health, global mental health, and depression. A multivariable linear regression analysis was performed to compare adjusted 1-year postoperative PROMIS scores between the 2 cohorts. Complication and revision rates were also compared.

Results

The study included 82 patients who underwent SCI hemiarthroplasty and 101 who underwent MTP joint arthrodesis. Demographic data and preoperative hallux rigidus severity showed no significant differences between the cohorts. PROMIS scores were mostly comparable between the 2 groups, except for the pain intensity domain. The patients who underwent MTP joint arthrodesis exhibited significantly better pain relief at 1 and 2 years postoperatively, which was supported by adjusted postoperative PROMIS scores. At 2 years, the SCI group had worse pain intensity scores and lower global physical health scores. There were no differences between the cohorts in additional PROMIS scores or complication data.

Conclusions

While outcomes in most of the domains were similar, MTP joint arthrodesis was more effective at mitigating pain intensity compared with SCI hemiarthroplasty. This information can guide patient counseling and decision-making when considering surgical intervention for hallux rigidus.

Level of Evidence

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Minimally invasive Dorsal cheilectomy and Hallux metatarsophalangeal joint arthroscopy for the treatment of Hallux Rigidus

BACKGROUND

Minimally invasive dorsal cheilectomy (MIDC) has become a popular alternative to an open approach for treating Hallux Rigidus (HR). To reduce some of the complications related to the MIDC approach, a first metatarsophalangeal (MTP) joint arthroscopy can be performed in addition to address the intra-articular pathology associated with Hallux Rigidus. This study aims to examine the effectiveness of MIDC with first MTP arthroscopy in patients with HR with a minimum 1-year follow-up.

METHODS

This was a multicenter retrospective review for adult patients with Coughlin and Shurnass Grade 0-3 who were treated with MIDC and first MTP arthroscopy between 3/1/2020 and 8/1/2022, with at least one year of follow-up data. Demographic information, first MTP range of motion (ROM), visual analog scale (VAS), Manchester-Oxford Foot Questionnaire (MOXFQ), and EQ-5D-5 L scores were collected. Continuous data was expressed as a mean and standard deviation, categorical data was expressed as a percentage. Wilcoxon Rank Sum test was used to compare continuous variables. All P < 0.05 was considered significant.

RESULTS

A total of 31 patients were included in the study. Average follow-up time was 16.5 months (range: 12 to 26.2). There was 1 (3.2%) undersurface EHL tendon tear, 2 (6.5%) conversions to an MTP fusion, and 1 (3.2%) revision cheilectomy and capsular release for MTP joint contracture. There was a significant improvement in patient's ROM in dorsiflexion (50 vs 89.6 degrees, P = 0.002), postoperative VAS pain scores (6.4 vs 2.1, P < 0.001), MOXFQ pain scores (58.1 vs 30.7, P = 0.001), MOXFQ Walking/Standing scores (56.6 vs 20.6, P = 0.001), MOXFQ Social Interaction scores (47.3 vs 19.36, P = 0.002), and MOXFQ Index scores (54.7 vs 22.4, P < 0.001).

CONCLUSION

We found that MIDC with first MTP arthroscopy was effective at improving patient-reported outcomes at one year with low complication and revision rates. These results suggest that MIDC with first MTP arthroscopy is an effective treatment for early-stage HR.

LEVEL OF EVIDENCE

IV.

Silicone Arthroplasty as an Alternative to Arthrodesis in the Metatarsophalangeal Degenerative Disease of Hallux Valgus-A 5-Year Observational Study

Background: Arthroplasty is gaining more and more popularity in the treatment of osteoarthritis (OA) of the metatarsophalangeal I joint (MTP1). The aim of our study was to evaluate the early and long-term objective clinical and radiographic results, as well as the subjective results, of MTP1 arthroplasty in comparison to MTP1 arthrodesis among patients with OA and a valgus deformity of their MTP 1 joint. Methods: Patients with OA MTP1 were examined before surgery and in the 5-year period after surgery. The inclusion criteria for the study were OA of the MTP1 joint and a non-axial position of the toe in valgus between 20 and 40 degrees. Prostheses were created for the patients with higher demands for mobility of their MTP 1 joint and arthrodesis was carried out for those with lower expectations. The treatment outcomes were assessed by clinical examination, radiography, the AOFAS scale, the SEFAS scale, and using patient-related outcome measures (PROM). Results: A total of 39 people, 37 women and 2 men, aged 55 to 67 years old (average, 61 years old) participated in the study. During the follow-up period, there were no complications in the form of infection or a loosening of the implant after both arthroplasty and arthrodesis. The follow-up examination 60 months after the surgery showed an improvement in scores (>20 points) on both the AOFAS and SEFAS scales. All patients, after surgery, reported reduced pain. Conclusions: The use of a silicone prosthesis in the surgical treatment of degenerative changes in the MTPI joint, with appropriate indications and excluding cases with large hallux valgus, gives better results than arthrodesis.

Polyvinyl alcohol hydrogel implant for the treatment of hallux rigidus is associated with a high complication rate and moderate failure rate at short-term follow-up: a systematic review

PURPOSE

Moderate-to-severe hallux rigidus is a debilitating pathology that is optimally treated with surgical intervention. Arthrodesis produces reliable clinical outcomes but is limited by restriction in 1st metatarsophalangeal joint range of motion. The advent of polyvinyl alcohol hydrogel (PVA) implants have produced early promise based on initial trials, but more recent studies have called into question the efficacy of this procedure. The purpose of this systematic review was to evaluate the clinical and radiological outcomes following the use of PVA for hallux rigidus.

METHODS

The MEDLINE, EMBASE and Cochrane library databases were systematically reviewed using the preferred reporting items for systematic reviews and meta-analyses guidelines. 18 studies were included.

RESULTS

In total, 1349 patients (1367 feet) underwent PVA at a weighted mean follow-up of 24.1 ± 11.1 months. There were 168 patients (169 feet) included in the cheilectomy cohort and 322 patients (322 feet) included in the arthrodesis cohort. All 3 cohorts produced comparable improvements in subjective clinical outcomes. Postoperative imaging findings in the PVA cohort included joint space narrowing, peri-implant fluid, peri-implant edema and erosion of the proximal phalanx. The complication rate in the PVA cohort, cheilectomy cohort and arthrodesis cohort was 27.9%, 11.8% and 24.1%, respectively. The failure rates in the PVA cohort, cheilectomy cohort and arthrodesis cohort was 14.8%, 0.3% and 9.0%, respectively.

CONCLUSION

This systematic review demonstrated that PVA produced a high complication rate (27.9%) together with concerning postoperative imaging findings at short-term follow-up. In addition, a moderate failure rate (14.8%) and secondary surgical procedure rate (9.5%) was noted for the PVA cohort. The findings of this review calls into question the efficacy and safety of PVA for the treatment of hallux rigidus.

LEVEL OF EVIDENCE

IV.

Polyvinyl Alcohol Hydrogel Hemiarthroplasty of First Metatarsophalangeal Joint Hallux Rigidus

Background Hallux rigidus (HR) is the most common arthritic condition of the foot. Although first metatarsophalangeal joint (MTPJ) arthrodesis has been the historical gold-standard treatment, polyvinyl alcohol (PVA) hydrogel implants have gained popularity as a joint-sparing technique. However, recent studies have shown variable failure rates of PVA hydrogel implants. The purpose of this study was to report the five-year experience with PVA hydrogel implants performed by a single surgeon. Methodology Health records were queried from August 2016 to 2021 for patients who underwent primary PVA hydrogel implant hemiarthroplasty for symptomatic late-stage HR. Patient demographics and postoperative outcomes variables were evaluated. Kaplan-Meier analysis was used to evaluate implant survival. A total of 146 PVA hydrogel implant procedures were performed with a minimum six-month follow-up. Results The majority of patients were female (n = 103, 70.5%), with a mean age of 58.1 (±10.1) years, body mass index of 27.3 (±5.2) kg/m2, and American Society of Anesthesiologists score <3 (n = 131, 89.7%). The majority had stage II or III disease (n = 115, 78.8%). Patients experienced significant improvement in visual analog scale score (p < 0.0001) and hallux dorsiflexion (p = 0.0005). There were 22 (15.1%) complications, including implant subsidence (n = 15, 10.3%), deep infection (n = 6, 4.1%), and hypertrophic ossification (n = 1, 0.7%). Revision surgeries were required in 12.3% (n = 18) of patients at an average of 9.4 (±9.2) months postoperatively. This included nine (6.2%) revision PVA hydrogel implant procedures and nine (6.2%) first MTJP arthrodesis. The one- and two-year survival rates for MTPJ arthrodesis (n = 9) were 95.9% and 86.3%, respectively. Conclusions In the largest single-surgeon series reported, first MTPJ hemiarthroplasty with a PVA hydrogel implant significantly improved pain and hallux dorsiflexion at an average of 14.5 months postoperatively. There was a high two-year survivorship of 86.3% until failure which required first MTPJ arthrodesis. Future studies should be performed to refine the indications for PVA hydrogel implants and identify risk factors.

Arthrodesis vs arthroplasty for moderate and severe Hallux rigidus: Systematic review

Hallux rigidus is the most frequent arthritis of the foot, due to multiple factors. Arthrodesis and interposition arthroplasty are treatments considered in advanced stages of the disease, when conservative treatment has failed. Although arthrodesis may be considered the technique recommended by multiple authors, for patients in whom joint mobility is to be preserved, arthroplasty could represent a reliable alternative. The purpose of this systematic review is to investigate and compare the clinical outcomes and complications of arthrodesis and interposition arthroplasty for moderate and severe stages of hallux rigidus.

METHODS

For this systematic review we searched COCHRANE, EMBASE, PUBMED databases. Twenty-six research papers were obtained, with a total of 1348 feet, which were included for qualitative analysis. The following groups were included: Cartiva hemiarthroplasty (286), double stem silicone arthroplasty (276), total metallic arthroplasty (394) and arthrodesis (392).

RESULTS

In the arthrodesis group, the AOFAS-HMI score was the most used, ranging from 36 to 45 in the preoperative period and from 79 to 89 in the postoperative period. The greatest improvement in the VAS PAIN score was from 86 to 4. The fusion rate was 98.6% of the total number of cases, the most frequent complication was pain due to material discomfort. In the total metallic arthroplasty group, the ROTO-GLIDE system reported an AOFAS score of 95 points, with low complication rates; but, with the TOEFIT-PLUS and BIOMED-MERCK systems, despite the good postoperative value, they report 37% and 15% revision due to aseptic loosening in the series with the longest follow-up, respectively. The Cartiva group showed a significative increase in FAAM ADL and FAAM SPORT from 59.4 to 90.4 and from 60.9 to 89.7, respectively; similarly, 20.5% implant removal and conversion to arthrodesis were reported. Finally, the double stem silicone arthroplasty group, in the series with the longest follow-up, it manages to improve the MOXFQ score from 78.1 to 11.0, with an average range of mobility of 22.3 degrees. Lysis was reported in 10% of cases.

CONCLUSIONS

Arthrodesis has proven to be the best option for the treatment of advanced hallux rigidus. Arthroplasty can be a valid option for patients who demand to maintain the range of mobility of the joint; however, it is important to inform about the complications that may arise in the short and medium term.

LEVEL OF CLINICAL EVIDENCE

II.

Return to Sport After First Metatarsophalangeal Arthrodesis: A Systematic Review

BACKGROUND

First metatarsophalangeal (MTP) arthrodesis is a common surgical intervention for addressing MTP pain and deformity. Despite great interest on the topic of return to sport (RTS) after first MTP arthrodesis in the literature, no systematic review exists on this topic. The purpose of this systematic review is to investigate RTS after first MTP arthrodesis.

METHODS

This study is a systematic review using PubMed, Web of Science, CINAHL, and MEDLINE from database inception until May 10, 2023. Search algorithm used was (MTPJ OR MTP OR "hallux rigidus" OR cheilectomy OR metatarsal OR metatarsophalangeal) AND (arthrodesis OR fusion) AND sport. Inclusion criteria were surgical intervention of first MTP arthrodesis and outcomes related to sport.

RESULTS

Ten articles were included out of 249 articles initially retrieved. Patients (n = 450) had a frequency weighted mean (FWM) age of 58.6 ± 5.1 years with a FWM follow-up time of 32.1 ± 18.9 months. A total of 153 patients (reported in 34.0% of patients) had a FWM postoperative Foot and Ankle Ability Measure Sport score of 70.4 ± 21.8 at final follow-up. For sporting activities reported by multiple studies (running, yoga, golf, hiking, tennis, elliptical, and biking), about 9.8% to 28.1% of patients (n = 69 reports) stated that sporting activity difficulty decreased, 67.2% to 87.5% of patients (n = 340 reports) stated that sporting activity remained the same, and 1.8% to 8.5% of patients (n = 23 reports) stated that sporting activity difficulty increased after first MTP arthrodesis depending on the sporting activity. One article reported RTS time of 11.7 ± 5.1 weeks after first MTP arthrodesis (n = 39).

CONCLUSION

RTS after first MTP arthrodesis is highly variable depending on patient and sport. Numerous different sporting activities have high rates of RTS after first MTP arthrodesis, with a majority of patients reporting similar or increased ability to perform sporting activities after surgery.

Patient Satisfaction Following Hallux Rigidus Treatment With a Synthetic Cartilage Implant

BACKGROUND

There remains no clear consensus on patient satisfaction and functional outcomes following synthetic cartilage implant (SCI) implantation for hallux rigidus. The purpose of this study was to review our experience at a single academic institution using an SCI for treatment of hallux rigidus.

METHODS

A retrospective review was performed of patients who underwent the SCI procedure for treatment of hallux rigidus between January 2017 and May 2019. Functional outcomes were evaluated using Patient-Reported Outcome Measures Informational System (PROMIS)-10 scores as well as a survey investigating patient satisfaction, self-reported clinical improvement, and changes in sporting ability. Patients were divided into satisfied versus unsatisfied subgroups, and between-group differences in preoperative variables and complications were reviewed. A total of 90 patients (96 implants) were included in this study. The mean follow-up time was 26.4 months.

RESULTS

In all, 81.2% of patients reported that their foot was "much improved" (55.2%) or "improved" (26.0%) since undergoing the SCI procedure, whereas a slightly lower percentage, 74.0%, stated that they were "extremely satisfied" (41.7%) or "satisfied" (32.3%) at final follow-up. Patients were able to tolerate higher impact sporting activities after the procedure, and 75.0% of patients stated they would have the same surgery again. PROMIS-10 T-scores averaged 54.2 points for physical health and 57.4 points for mental health. Only 2.1% of patients required conversion to arthrodesis. Significant differences between the satisfied versus unsatisfied subgroups were found in preoperative corticosteroid injection use (21.1% vs 41.1%, respectively; P = .029) and preoperative VAS pain score (8.2 vs 7.1, respectively; P = .036).

CONCLUSION

The SCI procedure can be a viable option for treating hallux rigidus with high satisfaction overall, increased sport activity levels, and a very low revision rate. However, maximizing patient satisfaction may require more careful consideration of preoperative prognosticators and extensive patient counseling to ensure realistic expectations for recovery time and individual outcome.

LEVEL OF EVIDENCE

Level IV: Retrospective case series.

A Novel Plating System for First Metatarsophalangeal Joint Arthrodesis: A Retrospective Comparison of Hybrid and Traditional Locking Plate Constructs

BACKGROUND

Dorsal plate fixation is commonly used for first metatarsophalangeal joint (1st MTPJ) arthrodesis and plate design continues to evolve. A new staple compression plate (SCP) design attempts to utilize the continuous compression of a nitinol staple across the fusion site while simultaneously providing the stability of a dorsal locked plate. Herein, we compare the radiographic, clinical, and patient-reported outcomes of 1st MTPJ joint arthrodesis using 2 dorsal locking plate constructs including a novel SCP construct.

METHODS

Forty-four patients who underwent 1st MTPJ arthrodesis between 2016 and 2020 were retrospectively evaluated. There were 2 group cohorts. Group 1 cohort included 23 patients who received a CrossRoads Extremity SCP, and Group 2 cohort included 21 patients who received a Stryker dorsal locking precontoured titanium plate (LPP). All patients were evaluated with radiographs, Patient-Reported Outcomes Measures Information System (PROMIS) outcome scores, and Foot Function Index (FFI).

RESULTS

The complication and union rates did not vary between groups with a fusion rate of 95.7% in the SCP group and 90.5 % in the LPP group. Similarly, we found no significant differences in PROMIS or FFI scores between the SCP and LPP plates.

CONCLUSION

Use of either dorsal locking plate construct for 1st MTPJ arthrodesis was associated with high union rates and comparable functional outcomes. As locked plate technology continues to evolve for 1st MTPJ arthrodesis, it is important that clinical outcomes are reported.

LEVELS OF EVIDENCE

Level IV.

Surgical Outcomes of Synthetic Cartilage Implant Hemiarthroplasty for Metatarsophalangeal Arthropathy

Introduction Metatarsophalangeal joint (MTPJ) arthropathy in the great toe causes considerable pain and debilitation, severely impacting quality of life. Traditional management options included conservative measures, steroid injections, and arthrodesis. New options include Cartiva, a synthetic cartilage hemiarthroplasty for the MTPJ. This prosthesis has evidence of improved pain and function without the sacrifice of joint movement seen with arthrodesis. However, the implant itself has mixed reviews. This study aims to identify the pre-, peri, and short-term post-surgical outcomes of Cartiva surgery and review the literature for existing reported outcomes. Methods We retrospectively reviewed a cohort of 22 consecutive Cartiva procedures between 2016 and 2022 in a single UK institution. Hospital records were analyzed for peri-operative complications, implant survival, additional operative interventions, patient-reported outcomes, and functional improvement. Results Twenty-one patients underwent Cartiva for the first MTPJ pathology and one for the third MTPJ pathology. Prior to surgery, 40.9% of patients had undergone alternative therapies, including MTPJ steroid injections (seven patients), cheilectomy (four patients), and bunionectomy (one patient). Total complication rates, inclusive of medical, surgical, and implant complications were 45.5% (10/22). Total reoperation rates were 18.2% (4/22) including two revisions to arthrodesis and two manipulations under anesthesia (MUA) with local anesthetic injection. At the final follow-up, 55% were still experiencing pain, 15% neurovascular symptoms, 10% swelling, and 50% stiffness or reduced range of movement. However, 85% of patients returned to usual activities of daily living within two years. Conclusion Cartiva surgery for metatarsophalangeal arthropathy has demonstrated outcomes of persistent pain, limited range of movement, and restricted function at short-term follow-up. Rates of reoperation and revision to arthrodesis were comparable with similar studies.

Outcomes of Operative Versus Nonoperative Management for Hallux Rigidus: A Tertiary Care Center Experience

Background This study aims to investigate and report the outcomes of various management modalities used for hallux rigidus, a common form of degenerative joint disease affecting the foot and ankle. The research focuses on understanding the pathophysiology, classification systems, and nonoperative approaches such as medical therapy, intra-articular injections, shoe modifications, and physical therapy. Surgical techniques, including joint-sparing and joint-sacrificing procedures, are explored, considering factors such as disease stage and patient preferences. Methods A retrospective cohort study was conducted at King Abdulaziz Medical City (KAMC), Riyadh. The study included all patients who were diagnosed with hallux rigidus from the period 2016 to 2022. Data were collected through the BESTCare system at KAMC. All the data were collected through Microsoft Excel (Microsoft Corporation, Redmond, Washington) and transferred for analysis. Statistical analysis was performed using the IBM SPSS Statistics for Windows, Version 25 (Released 2017; IBM Corp., Armonk, New York). Frequencies and percentages were used to detail categorical variables, whereas continuous variables were examined by the mean and standard deviation. A p-value of <0.05 was considered to report the statistical significance. Results A total of 84 patients were included. The majority were women (60.7%). Diabetes and hypertension were prevalent comorbidities, affecting 21.4% and 35.7% of patients, respectively. Nonoperative management was the most common approach (66.7%). Complications were minimal (2.4% infections, 1.2% metatarsalgia), and 67.9% of patients reported no persistence of symptoms after treatment. Conclusion The low complication rates and the lack of significant associations between treatment modalities and outcomes suggest the generally safe and effective nature of the employed interventions. These findings can guide clinicians in making informed decisions regarding the management of hallux rigidus, while also highlighting areas for further research to improve treatment strategies and outcomes.

Silastic Joint Arthroplasty as a Joint-Preserving Alternative for End-Stage Hallux Rigidus: Outcomes From 112 First Metatarsophalangeal Joint Arthroplasties

Aim Osteoarthritis of the first metatarsophalangeal joint (MTPJ) is a common forefoot problem affecting patients in later years. It leads to pain, gait problems, and difficulty with activities of daily living. Treatment is controversial and varies according to patient symptoms and surgeon preference. Arthrodesis remains the gold standard but it has its own complications. It is associated with adjacent joint arthritis and transfer metatarsalgia. The aim of this study was to analyze the outcome of double-stemmed silastic joint arthroplasty (Wright-Medical, Memphis, TN) for end-stage hallux rigidus. Methods This retrospective analysis included 117 consecutive first MTPJ silastic arthroplasties done between January 2016 and February 2023 for end-stage hallux rigidus. There were 77 females and 40 males with a mean age of 65 years (46-82 years). Radiological and clinical assessments were performed, and patient-reported outcome measure data (PROMS) and visual analogue scale (VAS) scores were collected pre- and post-operatively. Results Findings showed 99.1% survivorship following a silastic joint arthroplasty with a mean follow-up of four years (six months to seven years). The MOXFQ (Manchester Oxford Foot Questionnaire) score improved from a mean of 81 (59.8-100) to 13 (0-57). The mean VAS scores improved from 7.2 (5-10) to 1.5 (0-7) postoperatively. Five patients were lost to follow-up. Two patients developed deep infection and one required revision. The other patient with infection was lost to follow-up. In total 10 patients (8.9%) developed complications, out of which eight patients responded to simple treatments. Conclusion Results have shown good to excellent outcomes following a silastic arthroplasty of the first MTPJ for the treatment of end-stage hallux rigidus. The survivorship at a mean follow-up of four years was 99.1% and the patient satisfaction rate was 90.1%. As historically reported, we did not see any soft tissue reaction or progressive osteolysis in any of our patients. It provides comparable and predictable outcomes to joint fusion for end-stage arthritis.

Developing a core outcome set for foot and ankle disorders in rheumatic and musculoskeletal diseases: A scoping review and report from the OMERACT 2022 foot and ankle special interest group session

OBJECTIVES

Foot and ankle involvement is common in rheumatic and musculoskeletal diseases, yet high-quality evidence assessing the effectiveness of treatments for these disorders is lacking. The Outcome Measures in Rheumatology (OMERACT) Foot and Ankle Working Group is developing a core outcome set for use in clinical trials and longitudinal observational studies in this area.

METHODS

A scoping review was performed to identify outcome domains in the existing literature. Clinical trials and observational studies comparing pharmacological, conservative or surgical interventions involving adult participants with any foot or ankle disorder in the following rheumatic and musculoskeletal diseases (RMDs) were eligible for inclusion: rheumatoid arthritis (RA), osteoarthritis (OA), spondyloarthropathies, crystal arthropathies and connective tissue diseases. Outcome domains were categorised according to the OMERACT Filter 2.1.

RESULTS

Outcome domains were extracted from 150 eligible studies. Most studies included participants with foot/ankle OA (63% of studies) or foot/ankle involvement in RA (29% of studies). Foot/ankle pain was the outcome domain most commonly measured (78% of studies), being the most frequently specified outcome domain across all RMDs. There was considerable heterogeneity in the other outcome domains measured, across core areas of manifestations (signs, symptoms, biomarkers), life impact, and societal/resource use. The group's progress to date, including findings from the scoping review, was presented and discussed during a virtual OMERACT Special Interest Group (SIG) in October 2022. During this meeting, feedback was sought amongst delegates regarding the scope of the core outcome set, and feedback was received on the next steps of the project, including focus group and Delphi methods.

CONCLUSION

Findings from the scoping review and feedback from the SIG will contribute to the development of a core outcome set for foot and ankle disorders in RMDs. The next steps are to determine which outcome domains are important to patients, followed by a Delphi exercise with key stakeholders to prioritise outcome domains.

Republication of "Current Concepts Review: Hallux Rigidus"

Arthritis of the first metatarsophalangeal (MTP) joint, hallux rigid, is a common and disabling source of foot pain in the adult population. Hallux rigidus is characterized by diseased cartilage and large, periarticular osteophytes that result in a stiff, painful joint. Activity modification, sensible shoes, orthotics, anti-inflammatory medications and occasional intra-articular steroid injections can be attempted to alleviate the discomfort associated with hallux rigidus. A number of surgical options exist for the treatment of recalcitrant hallux rigidus. Cheilectomy is a useful treatment for dorsal impingement pain seen in mild hallux rigidus. A new polyvinyl alcohol hemi-arthroplasty implant has shown promising early and midterm results in the treatment of advanced hallux rigidus; however, arthrodesis of the first MTP joint remains the gold standard treatment for advanced hallux rigidus because of unpredictable outcomes after early-generation joint replacement implants.

Adhesive Hydrogel Building Blocks to Reconstruct Complex Cartilage Tissues

Cartilage has an intrinsically low healing capacity, thereby requiring surgical intervention. However, limitations of biological grafting and existing synthetic replacements have prompted the need to produce cartilage-mimetic substitutes. Cartilage tissues perform critical functions that include load bearing and weight distribution, as well as articulation. These are characterized by a range of high moduli (≥1 MPa) as well as high hydration (60-80%). Additionally, cartilage tissues display spatial heterogeneity, resulting in regional differences in stiffness that are paramount to biomechanical performance. Thus, cartilage substitutes would ideally recapitulate both local and regional properties. Toward this goal, triple network (TN) hydrogels were prepared with cartilage-like hydration and moduli as well as adhesivity to one another. TNs were formed with either an anionic or cationic 3rd network, resulting in adhesion upon contact due to electrostatic attractive forces. With the increased concentration of the 3rd network, robust adhesivity was achieved as characterized by shear strengths of ∼80 kPa. The utility of TN hydrogels to form cartilage-like constructs was exemplified in the case of an intervertebral disc (IVD) having two discrete but connected zones. Overall, these adhesive TN hydrogels represent a potential strategy to prepare cartilage substitutes with native-like regional properties.

High complication rates following revision first metatarsophalangeal joint arthrodesis: a retrospective analysis of 79 cases

BACKGROUND

The most common indications for revision of first metatarsophalangeal joint (MTPJ) arthrodesis are symptomatic failures of prior arthrodesis, failed hallux valgus correction, and failed MTPJ arthroplasty implants. However, the outcomes of revision MTPJ arthrodesis have rarely been studied. The purpose of this study was to compare the clinical, radiographic, and patient-reported outcomes of revision MTPJ arthrodesis following different primary procedures.

METHODS

A retrospective review of revision MTPJ arthrodesis cases between January 2015 and December 2019 was performed. The radiographic results, patient-reported outcomes, and rates of complications, subsequent revisions, and nonunions, were analyzed and compared preoperatively and postoperatively. A multivariate analysis was utilized to determine risk factors for complications and reoperations.

RESULTS

This study yielded a total of 79 cases of revision MTPJ arthrodesis. The mean follow-up time was 365 days (SD ± 295). The overall complication rate was 40.5%, of which the overall nonunion rate was 19.0%. Seven cases (8.9%) required further revision surgery. The multivariate analysis revealed that Diabetes mellitus was associated with significantly higher overall complication rates (p = 0.016), and nonunion was associated with "in-situ" joint preparation techniques (p = 0.042). Visual Analog Scale (VAS) significantly improved postoperatively (p < 0.001); However, PROMIS-10 physical health and PROMIS-10 mental health did not change significantly during the study period.

CONCLUSION

Treatment of MTPJ surgery failures is a clinical challenge in orthopedic surgery. In our study, revision of first MTPJ surgery resulted in higher nonunion rates and overall complication rates compared to typical outcomes from primary MTPJ arthrodesis. Diabetes, Tobacco use, and "in-situ" joint preparation technique were found to be independent risk factors for complications and reoperations.

LEVEL OF EVIDENCE

III-Retrospective Cohort Study.

Synthetic cartilage implant hemiarthroplasty versus cheilectomy for the treatment of hallux rigidus

Degenerative arthritis of the first metatarsophalangeal joint, hallux rigidus, is the most common type of arthritis of the foot, affecting nearly 2.5% of the population over the age of 50. Hallux rigidus can be treated surgically with either Cheilectomy or Synthetic cartilage implant (SCI) hemiarthroplasty. The purpose of this study is to compare outcomes from a single institution on the treatment of hallux rigidus using cheilectomy and SCI hemiarthroplasty. Between 2012 and 2020, 49 patients underwent either a SCI (Polyvinyl alcohol hydrogels) hemiarthroplasty or Cheilectomy for the treatment of hallux rigidus. Functional scores were assessed pre and postoperatively using the American Orthopedic Foot and Ankle scoring System (AOFAS) and the Foot and Ankle Outcome Score survey (FAOS). Plantar and Dorsal range of motion was also assessed pre and postoperatively. Outcomes, complications, and any reoperations were recorded for all patients. Mean pre-op AOFAS for Cheilectomy and SCI were 49.6 and 54.8, respectively, compared to 85.3 and 89.7, respectively, after surgery (p value < 0.05). Mean pre-op Dorsal range of motion (ROM) for Cheilectomy and SCI were 24.0 and 26.0 degrees, respectively, compared to 38.0 and 42.6 degrees, respectively, after surgery (p value < 0.05). SCI hemiarthroplasty patients had higher AOFAS and dorsal ROM at the latest follow up (p value < 0.05). Synthetic cartilage implant (SCI) hemiarthroplasty and cheilectomy both offer promising results and remain viable treatment options to decrease pain, improve function, and maintain motion for hallux rigidus. SCI hemiarthroplasty may offer superior range of motion and functional outcomes than cheilectomy for hallux rigidus. LEVEL OF CLINICAL EVIDENCE: 3.

Cationic Modified PVA Hydrogels Provide Low Friction and Excellent Mechanical Properties for Potential Cartilage and Orthopedic Applications

Poly(vinyl alcohol) (PVA) hydrogel is a promising candidate for articular cartilage repair yet restrained by its mechanical strength and tribological property. Current work reports a newly designed PVA-based hydrogel modified by glycerol (g), bacterial cellulose (BC), and a cationic polymer poly (diallyl dimethylammonium chloride) (PDMDAAC), which is a novel cationic strengthening choice. The resultant PVA-g-BC-PDMDAAC hydrogel proves the effectiveness of this modification scheme, with a confined compressive modulus of 19.56 MPa and a friction coefficient of 0.057 at a joint-equivalent load and low sliding speed. The water content, swelling property, and creep behavior of this hydrogel are also within a cartilage-mimetic range. The properties of PVA-based hydrogels before PDMDAAC addition are likewise studied as a cross-reference. Besides, PDMDAAC-modified PVA hydrogel realizes ideal mechanical and lubrication properties with a relatively low PVA concentration (10 wt.%) and facile fabrication process, which lays a foundation for mass production and marketization in the future.

Ultra-High Modulus Hydrogels Mimicking Cartilage of the Human Body

The human body is comprised of numerous types of cartilage with a range of high moduli, despite their high hydration. Owing to the limitations of cartilage tissue healing and biological grafting procedures, synthetic replacements have emerged but are limited by poorly matched moduli. While conventional hydrogels can achieve similar hydration to cartilage tissues, their moduli are substantially inferior. Herein, triple network (TN) hydrogels are prepared to synergistically leverage intra-network electrostatic repulsive and hydrophobic interactions, as well as inter-network electrostatic attractive interactions. They are comprised of an anionic 1^st network, a neutral 2^nd network (capable of hydrophobic associations), and a cationic 3^rd network. Collectively, these interactions act synergistically as effective, yet dynamic crosslinks. By tuning the concentration of the cationic 3^rd network, these TN hydrogels achieve high moduli of ≈1.5 to ≈3.5 MPa without diminishing cartilage-like water contents (≈80%), strengths, or toughness values. This unprecedented combination of properties poises these TN hydrogels as cartilage substitutes in applications spanning articulating joints, intervertebral discs (IVDs), trachea, and temporomandibular joint disc (TMJ).

Summary Report of the Arthritis Foundation and the American Orthopaedic Foot & Ankle Society's Symposium on Targets for Osteoarthritis Research: Part 2: Treatment Options

This second of a 2-part series of articles recounts the key points presented in a collaborative symposium sponsored jointly by the Arthritis Foundation and the American Orthopaedic Foot & Ankle Society with the intent to survey current treatment options for osteoarthritis (OA) of the foot and ankle. A meeting was held virtually on December 10, 2021. A group of experts were invited to present brief synopses of the current state of knowledge and research in this area. Topics were chosen by meeting organizers, who then identified and invited the expert speakers. Part 2 overviews the current treatment options, including orthotics, non-joint destructive procedures, as well as arthroscopies and arthroplasties in ankles and feet. Opportunities for future research are also discussed, such as developments in surgical options for ankle and the first metatarsophalangeal joint. The OA scientific community, including funding agencies, academia, industry, and regulatory agencies, must recognize the importance to patients of addressing the foot and ankle with improved basic, translational, and clinical research.

LEVEL OF EVIDENCE

Level V, review article/expert opinion.

Philosophies of Surgical Care Are Embedded in Outcome Studies: An Illustrative Reanalysis of the Cartiva MOTION Trial

BACKGROUND

Subjective assumptions on the definition of surgical success are inherent to the design of clinical trials with a categorial outcome. The current study used reasonable alternative assumptions about surgical care to reassess data for the randomized controlled Cartiva trial (MOTION).

METHODS

Data from the published study were augmented by publicly accessible internal US Food and Drug Administration documents. As in the published report, 1-sided lower bound 95% CIs (LBCI95) for the difference of proportions were calculated for a series of alternative scenarios in which the assumptions underlying what constitutes surgical success were altered.

RESULTS

Using a noninferiority margin of -15%, the MOTION trial reported success based on a 1-sided LBCI95 of -10.9%. Each of the 3 independent alternative scenarios analyzed yielded results that altered the primary outcome of the trial: (1) eliminating failures based solely upon radiographs findings, thereby considering a painless pseudarthrosis as a success (1-sided LBCI95 of -15.9%), (2) considering only major surgical revision as a failure and discounting isolated hardware removal (1-sided LBCI95 of -15.1%), and (3) using a visual analog scale (VAS) pain threshold of &lt;30 as the success criterion rather than a 30% reduction in VAS pain score (1-sided LBCI95 of -15.8%).

CONCLUSION

In this reanalysis, applying any of 3 reasonable alternative assumptions about the definition of surgical success to the data resulted in failure to prove noninferiority of Cartiva over arthrodesis, a reversal of the reported trial result. These results highlight the effect of subjective assumptions in the design of clinical trials with a categorical outcome and illustrate how differing philosophies about what constitutes surgical success can be pivotal in determining the final result.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

One-year Follow-Up Results with Hydrogel Implant in Therapy of Hallux Rigidus: Case Series with 44 Patients

BACKGROUND

The Cartiva implant (CI) is being increasingly used in the surgical therapy of hallux rigidus. Despite a growing number of studies, numerous questions regarding patient selection remain unanswered.

PATIENTS AND METHODS

As part of a retrospective case series with prospective follow-up (average follow-up period: 12 months), a total of 44 patients (male/female = 16/28; mean age at the time of surgery: 55.4 years) with 44 CI were analysed (VAS, EFAS-, AOFAS-score). Using a correlation analysis and a machine learning algorithm, risk factors for therapy failure were investigated.

RESULTS

The overall survival rate of the CI was 93% at 12 months. The VAS, EFAS and AOFAS scores showed a significant improvement in comparison to the preoperative condition. The mobility of the metatarsophalangeal joint showed no increase. Patients with a medium osteoarthritis grade and a medium level of clinical restraint showed the greatest improvement in relation to their preoperative condition.

CONCLUSION

The CI can be seen as an effective therapy for hallux rigidus. Nonetheless, realistic patient expectations must be communicated.

International Foot and Ankle Osteoarthritis Consortium review and research agenda for diagnosis, epidemiology, burden, outcome assessment and treatment

OBJECTIVE

To summarise the available evidence relating to the diagnosis, epidemiology, burden, outcome assessment and treatment of foot and ankle osteoarthritis (OA) and to develop an agenda to guide future research.

METHOD

Members of the International Foot and Ankle Osteoarthritis Consortium compiled a narrative summary of the literature which formed the basis of an interactive discussion at the Osteoarthritis Research Society International World Congress in 2021, during which a list of 24 research agenda items were generated. Following the meeting, delegates were asked to rank the research agenda items on a 0 to 100 visual analogue rating scale (0 = not at all important to 100 = extremely important). Items scoring a mean of 70 or above were selected for inclusion.

RESULTS

Of the 45 delegates who attended the meeting, 31 contributed to the agenda item scoring. Nineteen research agenda items met the required threshold: three related to diagnosis, four to epidemiology, four to burden, three to outcome assessment and five to treatment.

CONCLUSIONS

Key knowledge gaps related to foot and ankle OA were identified, and a comprehensive agenda to guide future research planning was developed. Implementation of this agenda will assist in improving the understanding and clinical management of this common and disabling, yet relatively overlooked condition.

Characteristics and research trends of 50 most-cited hallux rigidus papers

BACKGROUND

The bibliometric studies in the field of orthopaedics have gained popularity since they can determine the characteristics and research trends of most influential papers in specific subjects. This study aimed to evaluate the 50 most-cited articles related to hallux rigidus, and analyze possible factors associated with increased citation counts.

METHODS

The available literature about hallux rigidus on Web of Science database until January 2021 were analyzed and the 50 most-cited articles were determined. The characteristics of the papers were documented and analyzed for any relationship or correlation with total citation or citation per year (citation density) values.

RESULTS

The average citation number and citation density were 52.8 (range: 26-243) and 3 (range: 0.8-12.8), respectively. The average author number was 3.4, while the average institution number was 1.9. The USA had the highest number of articles with 29. Twenty-six papers were case-series, only 3 studies had level 1 and only 2 had level 2 evidence. The highest number of articles were published in Foot and Ankle International with 22 papers. Forty papers were clinical studies while 10 were reviews. Five studies were multicentric.

CONCLUSION

This study provided the general characteristic and research trends of 50 most influential hallux rigidus papers. The number of institutions and references were positively correlated with citation density, indicating a higher chance of getting cited for papers with collaborations from different institutions and papers using more references from other works. Publication year was also positively correlated with citation density, indicating the better performance of more recent articles.

LEVEL OF CLINICAL EVIDENCE

Level 3.

Postoperative Findings of Common Foot and Ankle Surgeries: An Imaging Review

Foot and ankle surgery is increasingly prevalent. Knowledge of the mechanisms underlying common foot and ankle deformities is useful in understanding surgical procedures used to restore normal biomechanics. As surgical techniques evolve, it is important for the radiologist to be familiar with these procedures, their expected postoperative appearance, and potential complications. This article reviews the key imaging findings of a variety of common and important foot and ankle surgical procedures.

First metatarsophalangeal joint arthrodesis/fusion: a systematic review of modern fixation techniques

Background

First metatarsophalangeal joint arthrodesis is commonly performed for symptomatic end-stage hallux rigidus. It has been postulated to produce good results in the literature. Various fixation techniques offer differences in union rates, complications and functional outcomes, stirring debates about which produces the best outcomes for patients. Therefore, this review aims to synthesise and compare the outcomes of modern fixation techniques used for first metatarsophalangeal joint (FMPJ) arthrodesis.

Methods

The electronic database searched were PubMed, CINAHL, Cochrane Library, and Google Scholar. The critical appraisal skills programme tool for cohort study was used. The interventions consisted of screw(s), plate(s), and staple(s). Studies comprising outdated fixation techniques such as suture, metallic wire, external fixation, Rush rods or Steinmann pins were excluded. Participants were adults over 18 years, undergoing FMPJ arthrodesis in the UK. Studies with the population consisting primarily of revision cases, patients with rheumatoid arthritis or diabetes were excluded.

Results

Seven UK studies included 277 feet and a 95.7% overall union rate at a mean union time of 83.5 days. Staples had the highest union rate of 98.2% at mean union time of 84 days, followed by plates (95.2%, 92 days), and finally screws (94.9%, 71 days). The overall complication incidence is 5.8%. All of the fixation techniques produced good functional outcomes postoperatively.

Conclusions

Whilst staple techniques showed the highest union rate, plating techniques are preferable over screws or staples for better results across several outcome measures, including reduced complication incidence, stability, early ambulation, and good functional outcome. The Manchester-Oxford Foot Questionnaire and EuroQol-5Dimensional are recommended as measurement tools to assess functional outcomes following FMPJ arthrodesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-022-00540-9.

Adverse Events Related to Cartiva Hemiarthroplasty of First Metatarsal: An Analysis of Reports to the United States Food and Drug Administration

Background: The results supporting Cartiva, a synthetic cartilage implant (Wright Medical) in hallux rigidus have come from limited institutions creating observational bias. Complications experienced in community centers are not routinely included in the published literature. To look at a broader range of potential complications, we reviewed the United States Food and Drug Administration's (FDA) voluntary device database and compared that data with published literature. Methods: The Manufacturer and User Facility Device Experience (MAUDE) database of the FDA was retrospectively reviewed between July 2016 and October 2019 using the product code: PNW, assigned for Cartiva. Results: A total of 49 events have been reported and implant subsidence was the most common with 16 reports. Others include fragmentation (9), infection (4), bone erosion (3), foreign body reaction (1) and unspecified (16). Thirty-five events mentioned further surgeries at a mean interval of 4.75 months. Conclusions: The analysis of the MAUDE database disclosed certain device-related dysfunctions that have been underreported in the published literature. Because of the voluntary nature of reporting, the true incidence of each complication is unknown with this data representing a baseline. The MAUDE database could be further strengthened by a more robust reporting mechanism or mandatory reporting of device-related complications.Levels of Evidence: Level IV: Case series from large database analysis.

Metallic hemiarthroplasty or arthrodesis of the first metatarsophalangeal joint as treatment for hallux rigidus: A systematic review and meta-analysis

BACKGROUND

Arthrodesis and metallic hemiarthroplasty are two surgical interventions for the treatment of end-stage osteoarthritis of the first metatarsophalangeal (MTP1) joint. This systematic review and meta-analysis aims to compare the two operations with regards to patient-reported outcomes, pain reduction, complications and revision rates.

METHODS

A systematic literature search identified all relevant studies. The methodological quality was assessed using two validated tools. Data of interest were derived and presented. For non-comparative studies, data was assessed for trends, while for comparative studies pooling statistics were performed.

RESULTS

A total of 33 studies were included for analysis. The majority of studies (>75%) reported an AOFAS-HMI score greater than 80 points after both metallic hemiarthroplasty and arthrodesis. The lowest VAS pain score was observed after arthrodesis (weighted mean difference -1.58, 95% confidence interval (CI) -2.16 to -1.00 P< 0.00001). Comparable numbers of complications (odds radio 1.48, 95% CI 0.81 to 2.73, P = 0.21, favoring: hemiarthroplasty) and revisions (odds ratio 1.16, 95% CI 0.62 to 2.15 P = 0.64, favoring: hemiarthroplasty) were observed after both interventions. The included non-comparative studies seem to confirm these findings of the comparative studies.

CONCLUSION

Metallic hemiarthroplasty and arthrodesis have excellent clinical outcomes and acceptable complication- and revision rates. Arthrodesis seems to be superior in pain reduction, while metallic hemiarthroplasty is a suitable alternative for patients performing activities that requires motion in the first metatarsophalangeal joint.

Management of Periprosthetic Polyvinyl Alcohol Synthetic Cartilage Implant Infection with Staged First Metatarsophalangeal Joint Arthrodesis

Surgical management of hallux rigidus using a polyvinyl alcohol synthetic cartilage implant has gained popularity among foot and ankle surgeons. Although uncommon, appropriate diagnosis and management of a periprosthetic implant infection is critical in limiting morbidity. We present a case report and staged technique for converting a first metatarsal synthetic cartilage hemiarthroplasty to arthrodesis in the setting of a periprosthetic joint infection.

Early Failure of a Polyvinyl Alcohol Hydrogel Implant With Osteolysis and Foreign Body Reactions in an Ovine Model of Cartilage Repair

BACKGROUND

Hemiarthroplasty using a polyvinyl alcohol (PVA) hydrogel synthetic implant has been suggested as a good alternative to arthrodesis for the treatment of hallux rigidus. However, failure rates as high as 20% have been recorded.

PURPOSE

To characterize the pathological processes in bone, cartilage, and the synovial membrane after PVA hemiarthroplasty in an ovine model with 6 months of follow-up.

STUDY DESIGN

Controlled laboratory study.

METHODS

A unilateral osteochondral defect (8-mm diameter × 10-mm depth) was made in the medial femoral condyle in 6 sheep. Animals were randomized to receive a PVA implant (n = 4) or to have an empty defect (n = 2) and were monitored for 6 months. Patellofemoral radiographs were obtained at monthly intervals, and quantitative computed tomography was performed at the end of the study. After death, the joints were macroscopically evaluated and scored. Osteochondral and synovial membrane histological findings were assessed using modified Osteoarthritis Research Society International (OARSI) and aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) scoring systems. Immunohistochemistry using Iba1 was performed to evaluate activated macrophage infiltration.

RESULTS

Overall, 2 sheep with PVA implants were euthanized at 1 and 5 months because of uncontrollable pain and lameness (failed implants). Quantitative computed tomography showed that sheep with failed implants had 2.1-fold more osteolysis than those with successful implants. The sheep with failed implants had osteoarthritis with extensive glycosaminoglycan loss and cartilage fibrillation of the condyle and opposing tibial surface on histological examination. A foreign body reaction with severe chronic lymphoplasmacytic and granulomatous inflammation with giant cells was detected surrounding the implant. The synovial membrane ALVAL score was 9 of 19 and 14 of 19 in failed implants with synovial hyperplasia and lymphoplasmacytic and macrophage infiltration. In contrast, the synovial membrane in successful implants and empty defects was normal (ALVAL score = 0/19). Immunolabeling for Iba1 in failed implants confirmed extensive and dense macrophage infiltration within the condyle and synovial membrane, with the highest immunoreactive score (9/9).

CONCLUSION

PVA hydrogel implants had a 50% failure rate with uncontrollable pain, severe osteolysis, inflammation, and foreign body reactions.

CLINICAL RELEVANCE

The failure rate and pathological characteristics of the PVA implants suggest that their use should not be continued in human patients without further in vivo safety studies.

Physical Function and Pain Interference Levels of Hallux Rigidus Patients Before and After Synthetic Cartilage Implant vs Arthrodesis Surgery

BACKGROUND

Hallux rigidus is a common and painful degenerative condition of the great toe limiting a patient's physical function and quality of life. The purpose of this study was to investigate pre- and postoperative physical function (PF) and pain interference (PI) levels of patients undergoing synthetic cartilage implant hemiarthroplasty (SCI) vs arthrodesis (AD) for treatment of hallux rigidus using the Patient-Reported Outcomes Measurement Information System (PROMIS).

METHODS

PROMIS PF and PI t scores were analyzed for patients who underwent either SCI or AD. Postoperative final PROMIS t scores were obtained via phone survey. Linear mixed model analysis was used to assess differences in PF and PI at each follow-up point. Final follow-up scores were analyzed using independent sample t tests.

RESULTS

Total 181 (59 SCI, 122 AD) operatively managed patients were included for analysis of PROMIS scores. Final phone survey was performed at a minimum of 14 (mean 33, range, 14-59) months postoperatively, with 101 patients (40 SCI, 61 AD) successfully contacted. The mean final follow-up was significantly different for SCI and AD: 27 vs 38 months, respectively (P < .01). The mean age of the SCI cohort was lower than the AD cohort (57.5 vs 61.5 years old, P = .01). Average PF t scores were higher in the SCI cohort at baseline (47.1 and 43.9, respectively, P = .01) and at final follow-up (51.4 vs 45.9, respectively, P < .01). A main effect of superior improvement in PF was noted in the SCI group (+4.3) vs the AD group (+2) across time intervals (P < .01). PI t scores were similar between the 2 procedures across time points.

CONCLUSION

The SCI cohort reported slightly superior PF t scores preoperatively and at most follow-up time points compared with the arthrodesis group. No differences were found for PI or complication rates between the 2 treatment groups during this study time frame.

LEVEL OF EVIDENCE

Level IV, case series.

Treatment of hallux rigidus (HARD trial): study protocol of a prospective, randomised, controlled trial of arthrodesis versus watchful waiting in the treatment of a painful osteoarthritic first metatarsophalangeal joint

INTRODUCTION

Hallux rigidus is a common problem of pain and stiffness of the first metatarsophalangeal joint (MTPJ) caused mainly by degenerative osteoarthritis. Several operative techniques have been introduced for the treatment of this condition without high-quality evidence comparing surgical to non-surgical care. In this trial, the most common surgical procedure, arthrodesis, will be compared with watchful waiting in the management of hallux rigidus.

METHODS AND ANALYSIS

Ninety patients (40 years or older) with symptomatic first MTPJ osteoarthritis will be randomised to arthrodesis or watchful waiting in a ratio of 1:1. The primary outcome will be pain during walking, assessed using the 0-10 Numerical Rating Scale (NRS) at 1 year after randomisation. The secondary outcomes will be pain at rest (NRS), physical function (Manchester-Oxford Foot Questionnaire), patient satisfaction in terms of the patient-acceptable symptom state, health-related quality of life (EQ-5D-5L), activity level (The Foot and Ankle Ability Measure Sports subscale), use of analgesics or orthoses and the rate of complications. Our null hypothesis is that there will be no difference equal to or greater than the minimal important difference of the primary outcome measure between arthrodesis and watchful waiting. Our primary analysis follows an intention-to-treat principle.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Ethics Committee of Helsinki and Uusimaa Hospital District, Finland. Written informed consent will be obtained from all the participants. We will disseminate the findings of this study through peer-reviewed publications and conference presentations.

PROTOCOL VERSION

21 June 2021 V.2.0.

TRIAL REGISTRATION NUMBER

NCT04590313.

The Use of a Synthetic Cartilage Implant for Hallux Rigidus: A Systematic Review

Background. Hallux rigidus is a common pathology afflicting the foot, for which various joint salvage techniques have been described with a multitude of different implants. Recently, a synthetic cartilage implant composed of polyvinyl alcohol (PVA) received FDA premarket approval for the treatment of arthritis of the great toe. The purpose of this study was to (1) systematically review the clinical evidence supporting the use of a PVA implant in hallux rigidus and (2) determine the strength of the recommendation that can be made supporting the use of a PVA implant by evaluating the quality of evidence available. Methods. A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. Using the terms "cartiva OR polyvinyl alcohol OR synthetic cartilage OR hemiarthroplasty AND hallux rigidus OR great toe arthritis OR first toe arthritis" we searched the PubMed/Medline database. The quality of the included studies was evaluated using the American Academy of Orthopaedic Surgeons Clinical Practice Guideline and Systematic Review Methodology. Results. Seven studies met the inclusion criteria, 6 of these were derived from a single randomized controlled trial. A moderate recommendation can be given for the use of a PVA implant for hallux rigidus based on short-term outcomes. A limited recommendation can be given for the use of a PVA implant for hallux rigidus based on mid-term outcomes. Conclusion. There are limited studies available detailing the outcomes of a PVA implant for hallux rigidus; however, the results that are available demonstrate a high level of evidence.Levels of Evidence: Level I: Systematic review.

A Novel Technique to Treat Hallux Rigidus in Athletic Patients With Central Osteochondral Defects: Preliminary Report on 12 Cases

Osteochondral defects, often caused by traumatic injuries, are focal areas of articular damage resulting in joint pain and stiffness ultimately leading to degenerative joint disease. This has not been well studied in the first metatarsal head, but is an often encountered problem in the active population in other joints. In this study, we prospectively evaluated the results of 12 patients who received autogenous bone grafting for repair of osteochondral defects of the first metatarsal head. Clinical outcomes were evaluated by the visual analog scale for pain and the Roles and Maudsley (RM) score. Between the years of 2009 and 2016, 12 patients received treatment for this particular surgical intervention and their outcomes were measured. The patients' average age was 43.5 ± 10.6 years and were followed from 52.3 ± 26.7 months postoperatively. Average return to activity was 4.7 ± 1.1 months. The average preoperative RM score was 4.0 ± 0.0 and postoperative RM score was 1.4 ± 0.7 (p = .0001). The encouraging outcomes of this study suggest that autogenous bone grafting for osteochondral defects of the first metatarsal head is an effective treatment to help restore the function of the first metatarsophalangeal joint.

Complications Associated with the Surgical Management of Hallux Rigidus

Hallux rigidus is the most common arthritic pathology of the foot. This review article discusses the pathophysiology and common clinical presentation of hallux rigidus. Furthermore, we discuss multiple classification systems that categorize the arthritic process and guide management. Surgical interventions include cheilectomy, Moberg osteotomy, synthetic cartilage implants, interpositional arthroplasty, and arthrodesis. The common complications are reviewed, and the rates of these complications highlighted. Surgical options for hallux rigidus globally have successful outcomes with low rates of complications when done on appropriate patients.

Synthetic Cartilage Implant Hemiarthroplasty for Second MTP Joint Osteoarthrosis

Synthetic cartilage hemiarthroplasty has been used successfully in the first metatarsophalangeal (MTP) joint and might also provide an alternative surgical intervention for second MTP joint osteoarthritis and Freiberg disease. Synthetic cartilage implant hemiarthroplasty was performed on 23 consecutive patients for the treatment of painful second MTP joint disease. Joint damage ranged from mild to severe. Mean follow-up period was 43 months ± 17.6 (range, 28-79 months). Mean age at the time of surgery was 55 years ± 16 (range, 20-73 years). Each participant attended for clinical assessment and an interview which included completion of 2 patient-reported outcome measures: the Manchester-Oxford Foot Questionnaire (MOXFQ) and the Foot and Ankle Ability Measure (FAAM). The implant failed in 2 participants (9%) and required removal and revision. Four participants (17%) reported dissatisfaction with the surgery because of continued pain. Nine participants (43%) reported second MTP joint stiffness; however, this was symptomatic in just 5 cases. Sixteen participants (70%) were pain free and totally satisfied with their outcome. Eleven of 21 participants (52%) reported an improvement in all 3 categories of the MOXFQ. FAAM scores demonstrated good overall function and activity, with a mean score of 91 ± 16 (range, 44-100). There were no postoperative infections, transfer metatarsalgia, or floating toe deformity. In preserving metatarsal and phalanx length as well as the collateral ligaments of the joint, synthetic cartilage implant hemiarthroplasty avoids some of the important risks of metatarsal osteotomy and basal phalangectomy. A range of alternative surgical options are still available if the synthetic cartilage implant fails to resolve symptoms.

Shoe-stiffening inserts for first metatarsophalangeal joint osteoarthritis: a randomised trial

OBJECTIVE

To evaluate the efficacy of carbon-fibre shoe-stiffening inserts in individuals with first metatarsophalangeal joint osteoarthritis.

DESIGN

This was a randomised, sham-controlled, participant- and assessor-blinded trial. One hundred participants with first metatarsophalangeal joint osteoarthritis received rehabilitation therapy and were randomised to receive either carbon fibre shoe-stiffening inserts (n = 49) or sham inserts (n = 51). The primary outcome measure was the Foot Health Status Questionnaire (FHSQ) pain domain assessed at 12 weeks.

RESULTS

All 100 randomised participants (mean age 57.5 (SD 10.3) years; 55 (55%) women) were included in the analysis of the primary outcome. At the 12 week primary endpoint, there were 13 drop-outs (7 in the sham insert group and 6 in the shoe-stiffening insert group), giving completion rates of 86 and 88%, respectively. Both groups demonstrated improvements in the FHSQ pain domain score at each follow-up period, and there was a significant between-group difference in favour of the shoe-stiffening insert group (adjusted mean difference of 6.66 points, 95% CI 0.65 to 12.67, P = 0.030). There were no between-group differences for the secondary outcomes, although global improvement was more common in the shoe-stiffening insert group compared to the sham insert group (61 vs 34%, RR 1.73, 95% CI 1.05 to 2.88, P = 0.033; number needed to treat 4, 95% CI 2 to 16).

CONCLUSION

Carbon-fibre shoe-stiffening inserts were more effective at reducing foot pain than sham inserts at 12 weeks. These results support the use of shoe-stiffening inserts for the management of this condition, although due to the uncertainty around the effect on the primary outcome, some individuals may not experience a clinically worthwhile improvement.