Early Outcomes and Complications of Synthetic Cartilage Implant for Treatment of Hallux Rigidus in the United States

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.

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.

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.

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.

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.

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.

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.

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.

Assessment and Management of Atraumatic First Metatarsophalangeal Joint Pain

Nontraumatic pain in the first metatarsophalangeal joint is frequent and can be debilitating. The metatarsophalangeal joint complex comprises four articulating surfaces including the first metatarsal, the proximal phalanx, and tibial and fibular sesamoids, which are all contained within a synovial capsule. The most common causes of pain are hallux valgus and hallux rigidus. However, other diagnoses, such as functional hallux limitus, sesamoiditis, gout, and inflammatory autoimmune arthritis, need to be considered as well. A systematic approach is key to accurately diagnose the source of pain, which can sometimes be the result of more than one condition. The most important clinical information to obtain is a focused history, meticulous clinical examination based on understanding the precise anatomy and biomechanics of the first metatarsophalangeal joint, and analysis of the relevant imaging. Each pathology has a different treatment algorithm, as such, understanding the pathoanatomy and biomechanics is important in forming an effective treatment plan.

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.

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.

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.

Complications of Hallux Rigidus Surgery

Hallux rigidus can be treated with a variety of surgical procedures, including joint preserving techniques, arthrodesis, and arthroplasty. The most commonly reported complications for joint preserving techniques consist of progression of arthritis, continued pain, and transfer metatarsalgia. Although good outcomes have been reported for arthrodesis overall, careful attention must be paid to technique and positioning of the toe to avoid nonunion or malunion. Arthroplasty preserves motion but in the case of failure can present the additional challenge of bone loss. In these scenarios, the authors recommend distraction bone block arthrodesis with structural autograft.

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.

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.

[Description of a technique that uses Lapidus arthrodesis plus osteochondral autotransplantation in the treatment of severe hallux rigidus]

OBJECTIVE

The objective of this technique is the treatment a severe hallux rigidus deformity by reorientation of an elevated first metatarsal using arthrodesis of the first tarsometatarsal joint and performing a one-step transplantation of an osteochondral graft, which is harvested from the first cuneiform, to the head of the first metatarsal bone.

INDICATIONS

Severe arthritis of the first metatarsophalangeal joint (MTP) stage 3 and 4 in the Vanore classification.

CONTRAINDICATIONS

General contraindications for a foot surgery; ankylosis of MTP joint; severe arthritis of the sesamoid joint; osteonecrosis; short first metatarsal; previous infection in the metatarsophalangeal joint; large cysts at the head of the first metatarsal.

SURGICAL TECHNIQUE

The first step is the preparation of the metatarsophalangeal and the first tarsometatarsal joint. After mobilizing the first metatarsal in a medioplantar direction, a cartilage-bone cylinder is removed from the articular surface of the medial cuneiform using special osteochondral autograft transfer system (OATS) instruments (Small Joint OATS, Arthrex medical instruments GmbH, Munich, Germany). This is followed by the arthrodesis of the first tarsometatarsal joint with reorientation of the position of the first metatarsal bone. Then the removed osteochondral cylinder is implanted into the articular surface of the first metatarsal head. After that the capsule is closed and the skin sutured.

POSTOPERATIVE MANAGEMENT

Postoperative management is guided mainly by the requirements of the first tarsometatarsal arthrodesis. When a plantar plate is used pain orientated full weightbearing is allowed in a postoperative shoe with a stiffened sole for 6-8 weeks. Physiotherapy is prescribed to exercise the first metatarsophalangeal joint.

RESULTS

In the study, 5 patients were treated with the method described in the years 2011-2012 and were followed up for a period of 2 years. All of these patients were subjectively satisfied with the outcome of the operation. There were no relevant surgery-associated complications.

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.

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.

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.

Adverse events involving hallux metatarsophalangeal joint implants: Analysis of the United States Food and Drug Administration data from 2010 to 2018

BACKGROUND

The prevalence of osteoarthritis of the hallux metatarsophalangeal joint (MTPJ) is 1 in 40 people over the age of 50. Surgical treatment options for MTPJ arthritis include joint preservation, joint resurfacing, and arthrodesis. Hallux MTPJ implants have evolved over the past several decades, but are associated with various complications. The aim of this study was to examine the MAUDE database to determine reported adverse events for hallux MTPJ implants.

MATERIALS AND METHODS

The US Food and Drug Administration's (FDA) Manufacturer and User Facility Device Experience (MAUDE) database was reviewed from 2010 to 2018 to review voluntary reported adverse event reports for approved implants within the United States. We recorded the type of adverse event and excluded duplicate reports and those extracted from already published literature.

RESULTS

Among 64 reported hallux MTPJ implant adverse events, the most common modes of adverse events were component loosening (34%), infection (14.1%), component fracture (9.4%), inflammation (9.4%), and allergic reaction (7.8%). Regarding implant type, Cartiva SCI had the highest percentage of adverse events (23.4%), followed by Arthrosurface ToeMotion (20.3%), Ascension MGT (12.5%), Arthrosurface HemiCAP® (10.9%), Futura primus (9.4%), and Osteomed Reflexion (6.3%). There was an increase in reported adverse events after 2016. The MAUDE database does not report the total incidence of implant insertion.

CONCLUSION

Our study of the MAUDE database demonstrated that component loosening and infection are the most common modes of adverse events for hallux MTPJ implants. Cartiva accounted for one-fourth of the implant-related adverse events during our study period, followed by ToeMotion, and Ascension MGT implants. Continued reporting of adverse events will improve our understanding on short and long-term complications of various hallux MTPJ implants.

LEVEL OF EVIDENCE

Level IV; Case Series from Large Database Analysis; Treatment Study.

Early Failures of Polyvinyl Alcohol Hydrogel Implant for the Treatment of Hallux Rigidus

BACKGROUND

The purpose of this study was to evaluate the clinical and radiological outcomes following a polyvinyl alcohol hydrogel implant in the treatment of hallux rigidus.

METHODS

A retrospective cohort study investigating patients treated with a polyvinyl alcohol hydrogel implant for hallux rigidus was performed. Clinical outcomes were evaluated with the Foot and Ankle Outcomes Score (FAOS) and visual analog scale (VAS) score at the final follow-up. Plain radiographs were assessed postoperatively. Eleven patients (11 feet) with a mean follow-up of 20.9 months (range, 14-27 months) were included. The mean age was 60.3 years.

RESULTS

All FAOS subscales showed pre- to postoperative improvements, but there was no statistical significance in all subscales. The mean VAS score showed improvement from 4.1 to 3.0 (P = .012). On postoperative plain radiographs, implant subsidence was observed 60% (6/10) at 4 weeks after surgery and 90% (9/10) at the final follow-up. Fifty percent (5/10) showed radiologic lucency around the implant. Forty percent (4/10) had erosion of the proximal phalanx of the great toe. Four patients (36%) reported no improvement following surgery at the final follow-up, which were considered as failures. Three patients required additional surgery related to the implants. An additional patient is waiting to revise the implant.

CONCLUSION

Our current cohort study demonstrated a high failure rate with the polyvinyl alcohol hydrogel implant in patients with hallux rigidus. Significant radiologic subsidence with lysis around the implant, erosion of the proximal phalanx countersurface, and implant wear are harbingers for concern in the long term.

LEVEL OF EVIDENCE

Level IV, case series.

[Mini implants in foot and ankle surgery: an alternative to total joint replacement or joint fusion]

Mini implants are increasingly used in foot and ankle surgery. They preserve the joints' functions, are easy to insert and easy to convert to an alternative treatment. Early surgical attempts using silastic implants did not bring the expected success. First achievements where reached with modern metallic mini implants in the first metatarsophalangeal (MTP) joint and the ankle joint. For a few years now, a polyvinyl alcohol implant has been used to treat the arthritic first MTP joint. Even severe arthritic joints can be treated with an implant made of polylactide. This implant can also be used in the treatment of Lisfranc joint pathologies. To address severe osteochondral defects of the talus, an innovative hemiarthroplasty implant has been suggested. This article gives a summary of currently used mini implants. Their application as possible alternatives to total joint replacement or joint fusion are critically reviewed in the light of the current literature.

Early Catastrophic Failure of a Synthetic Cartilage Implant for Hallux Rigidus

Hallux rigidus is a common arthritic disorder of the foot. Surgical treatments are varied, from isolated cheilectomy to arthrodesis. A synthetic cartilage implant has been embraced recently as a joint-sparing alternative to arthrodesis, with good early and midterm outcomes. However, early clinical failures have been described relating to implant subsidence. This case report focuses on another mode of failure consisting of early catastrophic wear resulting in conversion to a lengthening arthrodesis at short-term follow-up.Levels of Evidence: Level V.

Minimally Invasive Dorsal Cheilectomy and Hallux Metatarsal Phalangeal Joint Arthroscopy for the Treatment of Hallux Rigidus

Background:

Hallux rigidus (HR) is a common source of forefoot pain and disability. For those who fail nonoperative treatment, minimally invasive dorsal cheilectomy (MIDC) is an increasingly popular alternative to the open approach with early positive results. Early failures may be due to lose bone debris from the MIDC as well as other intra-articular pathology that cannot be addressed with MIDC alone. Metatarsophalangeal (MTP) arthroscopy can be used in addition to MIDC to assess the joint after MIDC and address any intra-articular pathology while still maintaining the benefits of minimally invasive surgery. We report our clinical outcomes following MIDC combined with MTP arthroscopy.

Methods:

From November 2017 to July 2020, a retrospective analysis of all MIDC cheilectomies with MTP arthroscopy performed by the 2 senior authors was done. Wound complications, infections, revision rates, need for future surgery, conversion to fusion rates, pre- and postoperative range of motion, visual analog scale (VAS) scores, time to return to normal shoe, intraoperative arthroscopic findings, and operative time were collected. Follow-up average was 16.5 months (range 3-33 months).

Results:

A total of 20 patients were included with an average follow-up of 16.5 months. The average VAS score improved from 7.05 preoperatively to 0.75 postoperatively ( P < .05). Average range of motion in dorsiflexion increased from 32 to 48 degrees ( P < .05) and plantarflexion increased from 15 to 19 degrees plantarflexion ( P < .05). All patients were weightbearing as tolerated immediately after surgery in a postoperative shoe and transitioned to a regular shoe at average of 2.1 weeks. We had no wound infections, wound complications, revision surgeries, tendon injuries or nerve damage. One patient required conversion to a fusion 3 years after the index procedure. Average tourniquet time was 30.39 minutes (range 17-60 minutes) and total average operating room time was 59.7 minutes (range 40-87 minutes). On arthroscopic evaluation of the MTP joint after MIDC, 100% of patients had bone debris, 100% had synovitis, 10% had loose bodies, and 30% had large cartilage flaps within the joint.

Conclusion:

MIDC and first MTP joint arthroscopy for treatment of hallux rigidus provide improved pain relief with minimal complications while still maintaining the benefits touted for minimally invasive operative procedures. Additionally, we have shown a high rate of intra-articular debris along with intra-articular pathology such as synovitis, loose chondral flaps, and loose bodies that exist after MIDC. This combined procedure has the potential for improving patient outcomes and may minimize risk of future revision surgeries compared with MIDC alone.

Level of Evidence:

Level IV, case series study.

Comparison Between Polyvinyl Alcohol Implant and Cheilectomy With Moberg Osteotomy for Hallux Rigidus

BACKGROUND

In 2016, the US Food and Drug Administration (FDA) approved the use of a polyvinyl alcohol (PVA) hydrogel implant for the surgical management of hallux rigidus. Though recent studies have evaluated the safety and efficacy of the implant, no study has compared outcomes following PVA implantation with those following traditional joint-preserving procedures for hallux rigidus, such as cheilectomy with Moberg osteotomy. The purpose of this study was to compare clinical and patient-reported outcomes for patients undergoing cheilectomy and Moberg osteotomy, with or without PVA implant, at a single multisurgeon academic center. Our hypothesis was that the addition of the PVA implant would result in superior clinical and patient-reported outcomes.

METHODS

In total, 166 patients were identified who underwent cheilectomy and Moberg osteotomy with (PVACM; n = 72) or without (CM; n = 94) a PVA implant between January 2016 and December 2018 by 1 of 8 foot and ankle fellowship-trained orthopedic surgeons at our institution. Of these patients, 60 PVACM and 73 CM patients had both baseline and minimum 1-year postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) scores. The average time to survey follow-up was 14.5 months for PVACM patients and 15.6 months for CM patients. Retrospective chart review was performed to assess the incidence of postoperative complications and reoperations, with an average clinical follow-up of 27.7 (range, 16.0-46.4) months for PVACM patients and 36.6 (range, 18.6-47.8) months for CM patients.

RESULTS

Both PVACM and CM cohorts demonstrated significant improvement in the PROMIS Physical Function, Pain Interference, Pain Intensity, and Global Physical Health domains when comparing preoperative and postoperative scores within each group (P < .01). When comparing scores between the PVACM and CM cohorts, preoperative scores were similar, while CM patients demonstrated significantly higher postoperative Physical Function (51.8 ± 8.7 vs 48.8 ± 8.0; P = .04) and significantly lower Pain Intensity (39.9 ± 8.3 vs 43.4 ± 8.7; P = .02) scores. The pre- to postoperative change in Physical Function was also significantly greater for CM patients (7.1 ± 8.5 vs 3.6 ± 6.2; P = .011). In the PVACM group, there were 3 revisions (5%), 1 reimplantation, 1 conversion to arthrodesis, and 1 revision to correct hyperdorsiflexion. In the CM group, there was 1 revision (1.4%), a conversion to arthrodesis (P = .21). Other postoperative complications included persistent pain (7 out of 60 PVACM patients [11.7%] and 8 out of 73 CM patients [11.0%]; P = .90) and infection in 3 PVACM patients (5%) and no CM patients (P = .05).

CONCLUSION

Though our results generally support the safety and utility of the PVA implant as previously established by the clinical trial, at 1 to 2 years of follow-up, CM without a PVA implant may provide equivalent or better relief compared with a PVACM procedure, while avoiding potential risks associated with the implant.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Clinical Outcomes of the Polyvinyl Alcohol (PVA) Hydrogel Implant for Hallux Rigidus

BACKGROUND

Hallux rigidus is a common arthritic condition that has been addressed surgically with a range of techniques, from an isolated cheilectomy to first metatarsophalangeal (MTP) joint fusion. Recently, hemiarthroplasty with polyvinyl alcohol (PVA) hydrogel implant has been used as an alternative treatment to relieve pain while preserving motion of the first MTP joint. We retrospectively reviewed patient-reported outcome scores and clinical outcomes for patients treated for hallux rigidus with PVA hydrogel implant at an academic, multisurgeon center.

METHODS

A total of 103 patients who underwent first MTP hemiarthroplasty with PVA hydrogel implant between January 2017 and October 2018 were retrospectively reviewed (average, 26.2 months). Eight surgeons were represented. Baseline Patient-Reported Outcomes Measurement Information System (PROMIS) scores for the Physical Function, Pain Interference, Pain Intensity, Global Physical Health, Global Mental Health, and Depression domains were collected prospectively and compared with PROMIS scores collected at a minimum of 1 year postoperatively (average, 13.9 months). Seventy-three patients had both preoperative and postoperative scores. Ten of these patients had undergone a prior procedure of the first MTP, and 52 underwent concurrent Moberg osteotomy at the time of PVA hydrogel implantation.

RESULTS

For patients with baseline and postoperative PROMIS scores, significant pre- to postoperative improvement was detected for the Physical Function, Pain Interference, Pain Intensity, and Global Physical Health domains (P < .05). Patients who had undergone a prior procedure of the first MTP had significantly higher postoperative Pain Intensity scores compared with those who did not undergo a prior procedure. Patients undergoing concurrent Moberg osteotomy had significantly lower postoperative Pain Interference and Pain Intensity scores compared with those who did not undergo a Moberg. Two patients underwent revision procedures in the first 2 years postoperatively, one with revision hemiarthroplasty and one with conversion to arthrodesis.

CONCLUSION

On average across our entire cohort, physical function and pain scores improved significantly pre- to postoperatively; however, postoperative pain scores were significantly higher for patients who had undergone a prior procedure of the first MTP and significantly lower for patients who underwent concurrent Moberg osteotomy. The implant displayed excellent survivorship in the first 2 years postoperatively, with only 2 revision procedures.

LEVEL OF EVIDENCE

Level III, comparative series.

Patient-Reported Outcomes and Early Complications After Synthetic Cartilage Device Implantation

Background:

Previous Level I studies show promising results for the use of a hydrogel synthetic cartilage implant (SCI) for the treatment of hallux rigidus. A recent independent retrospective review has put those results into question, however. The purpose of this article is to report patient-reported outcomes and early complications using this implant so as to add to the paucity of data in the literature regarding this implant.

Methods:

This was a retrospective chart review of patients undergoing hydrogel synthetic cartilage implant for the treatment of hallux rigidus from July 2017 to November 2018. Data collected included patient demographics, radiographic grading, and outcomes: Veterans Rand 12 Item Health Survey (VR-12), Foot and Ankle Ability Measure (FAAM), visual analog scale (VAS), patient satisfaction, and complications. Fifty-four patients (59 feet) with an average age of 57.6 (range, 39-78) years were analyzed. The average latest follow-up was 18.9 (range, 3-31.3) months. Body mass index was 26.7 (range, 18.7-35.2). None were diabetic and 5 were smokers.

Results:

The mean outcome improvements were 6.5 points (VR-12 Physical), 17.2 points (FAAM ADL), 27.4 points (FAAM Sport), and 18.4 points (VAS) (P < .01 for each). Scores were significantly improved from preoperatively to most recent follow-up for FAAM ADL (71.0 vs 88.2 points), FAAM Sports (44.6 vs 72.0 points), and VAS (49.4 vs 31.0) (P < .01). Overall, 72.5% patients would definitely or probably have the operation again. Ten patients (18.5%) went on to have revision surgery. Of these, 7 patients were revised to an arthrodesis, and 1 metal hemiarthroplasty and 2 implants were removed because of infection.

Conclusion:

Synthetic cartilage implantation for the treatment of hallux rigidus demonstrated improved pain and outcome scores at short-term follow-up. Reoperation and conversion to fusion rates were comparable to prior studies.

Level of Evidence:

Level IV, case series.

Silastic first metatarsophalangeal joint arthroplasty for the treatment of end-stage hallux rigidus

AIMS

Arthroplasty for end-stage hallux rigidus (HR) is controversial. Arthrodesis remains the gold standard for surgical treatment, although is not without its complications, with rates of up to 10% for nonunion, 14% for reoperation and 10% for metatarsalgia. The aim of this study was to analyze the outcome of a double-stemmed silastic implant (Wright-Medical, Memphis, Tennessee, USA) for patients with end-stage HR.

METHODS

We conducted a retrospective review of 108 consecutive implants in 76 patients, between January 2005 and December 2016, with a minimum follow-up of two years. The mean age of the patients at the time of surgery was 61.6 years (42 to 84). There were 104 females and four males. Clinical, radiological, patient reported outcome measures (PROMS) data, a visual analogue score (VAS) for pain, and satisfaction scores were collected.

RESULTS

The survivorship at a mean follow-up of 5.3 years (2.1 to 14.1) was 97.2%. The mean Manchester Oxford Foot and Ankle Questionnaire (MOXFQ) scores improved from 78.1 to 11.0, and VAS scores for pain from 7/10 to 1.3/10. The rate of satisfaction was 90.6%. Three implants (2.8%) required revision; one for infection, one-month postoperatively, and two for stem breakage at 10.4 and 13.3 years postoperatively. There was a 1.9% reoperation rate other than revision, 23.1% of patients developed a minor complication, and 21.1% of patients had non-progressive and asymptomatic cysts on radiological review.

CONCLUSION

We report a 97.2% survivorship at a mean follow-up of 5.3 years with this implant. We did not find progressive osteolysis, as has been previously reported. These results suggest that this double-stemmed silastic implant provides a predictable and reliable alternative with comparable outcomes to arthrodesis for the treatment of end-stage HR. Cite this article: Bone Joint J 2020;102-B(2):220-226.

Radiographic and Magnetic Resonance Imaging of the Symptomatic Synthetic Cartilage Implant

BACKGROUND

Synthetic Cartilage Implantation (SCI; Cartiva) is a treatment of hallux rigidus associated with mixed clinical outcomes in the United States. Patients with persistent pain typically undergo diagnostic imaging for evaluation. We aimed to characterize the radiologic findings of SCI and surrounding tissues.

METHODS

This is a retrospective review of patients treated using SCI who underwent magnetic resonance imaging (MRI) for persistent pain. Metatarsophalangeal (MTP) joint spaces were compared on plain radiographs of the foot immediately postoperatively and at most recent follow-up. MRI of the foot were assessed for dimensions of the implant, bony channel, and presence of peri-implant fluid. Clinical follow-up, including Patient-Reported Outcome Measures Informational System (PROMIS) scores, satisfaction rating, and revision surgery, was collected. Eighteen cases of symptomatic SCI from 16 patients (13 females, 3 males) were included. All but 1 case involved a 10-mm implant.

RESULTS

Mean satisfaction rating was 2.25 (1-5 Likert scale). PROMIS scores indicated moderate physical dysfunction (41) and moderate pain interference (63). Six of 16 patients (37.5%) underwent revision surgery at average 20.9 months of follow-up. Plain radiographs over a 13.3-month interval showed joint space narrowing of 2 mm medially and 1.6 mm laterally (P < .001). One hundred percent of cases had radiographic evidence of osteoarthritis (OA) progression. MRI studies were obtained on average 11.5 months postoperatively. The implant diameter averaged 9.7 mm, which mismatched the bony channel diameter of 11.2 mm (P < .001). Fourteen of 18 cases had peri-implant fluid. All cases had edema in the metatarsal, proximal phalanx, and soft tissues.

CONCLUSION

Radiographic loss of MTP joint space and progression of arthritis were present for all cases studied. MRI revealed bony channel widening and a smaller implant, with peri-implant fluid suggesting instability at the implant-bone interface. Persistent edema was observed in soft tissues and bone. Diagnostic imaging of SCI in symptomatic patients demonstrated concerning findings that merit further correlation with patient outcomes.

LEVEL OF EVIDENCE

Level IV, case series.