Comparison of the HINTEGRA and Mobility total ankle replacements

The significance of heterotopic ossification following total ankle arthroplasty: a systematic review and meta-analysis

PURPOSE

The purpose of this systematic review and meta-analysis was to evaluate the prevalence and clinical significance of heterotopic ossification (HO) following total ankle replacement (TAR).

METHODS

During August 2023, the PubMed, Embase and Cochrane library databases were systematically reviewed to identify clinical studies reporting HO following TAR. Data regarding surgical characteristics, pathological characteristics, subjective clinical outcomes, ankle range of motion, radiographic outcomes, reoperation rates were extracted and analysed.

RESULTS

Twenty-seven studies with 2639 patients (2695 ankles) at a weighed mean follow-up time of 52.8 ± 26.9 months were included. The pooled prevalence rate was 44.6% (0.25; 0.66). The implant with the highest rate of HO was the INBONE I (100%) and BOX (100%) implants. The most common modified Brooker staging was grade 1 (132 patients, 27.0%). Random effects models of standardized mean differences found no difference in American orthopedic foot and ankle society (AOFAS) scores, visual analog scale scores (VAS) and ankle range of motion (ROM) between patients with HO and patients without HO. Random effects models of correlation coefficients found no correlation between AOFAS, VAS and ROM and the presence of HO. The surgical intervention rate for symptomatic HO was 4.2%.

CONCLUSION

This systematic review and meta-analysis found that HO is a common finding following TAR that is not associated with inferior clinical outcomes. Surgical intervention was required only for moderate-to-severe, symptomatic HO following TAR. This study is limited by the marked heterogeneity and low level and quality of evidence of the included studies. Further higher quality studies are warranted to determine the precise prevalence and impact of HO on outcomes following TAR.

LEVEL OF EVIDENCE III

Patient-related risk factors associated with poorer outcomes following total ankle arthroplasty

Aims

This scoping review aims to identify patient-related factors associated with a poorer outcome following total ankle arthroplasty (TAA).

Methods

A scoping review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A computer-based literature search was performed in PubMed, Embase, Cochrane trials, and Web of Science. Two reviewers independently performed title/abstract and full-text screening according to predetermined selection criteria. English-language original research studies reporting patient-related factors associated with a poorer outcome following TAA were included. Outcomes were defined as patient-reported outcome measures (PROMs), perioperative complications, and failure.

Results

A total of 94 studies reporting 101,552 cases of TAA in 101,177 patients were included. The most common patient-related risk factor associated with poorer outcomes were younger age (21 studies), rheumatoid arthritis (17 studies), and diabetes (16 studies). Of the studies using multivariable regression specifically, the most frequently described risk factors were younger age (12 studies), rheumatoid arthritis (eight studies), diabetes (eight studies), and high BMI (eight studies).

Conclusion

When controlling for confounding factors, the most commonly reported risk factors for poor outcome are younger age, rheumatoid arthritis, and comorbidities such as diabetes and increased BMI. These patient-related risk factors reported may be used to facilitate the refinement of patient selection criteria for TAA and inform patient expectations.

Ten-Year Follow-Up of a Customized Total Talar Prosthesis for Revision Total Ankle Arthroplasty: A Case Report

CASE

A 74-year-old woman with rheumatoid arthritis had undergone total ankle arthroplasty (TAA) for severe ankle joint destruction at our hospital 14 years earlier. Radiographs of the ankle revealed displacement of the tibial component and subsidence of the talar component. Revision TAA was performed using a customized alumina ceramic total talar prosthesis.

CONCLUSION

The 10-year outcome of revision TAA with a total talar prosthesis was satisfactory, with no postoperative complications, such as displacement of the tibial component, dislocation of alumina ceramic artificial talus, or progression of degenerative changes in the talonavicular and subtalar joints.

Rol de la alineación de la prótesis y las calcificaciones heterotópicas en la artroplastia total de tobillo

Introducción: El objetivo principal fue evaluar la relación entre la formación de calcificaciones heterotópicas y los parámetros de alineación de la prótesis. Materiales y Métodos: La población estaba formada por 31 pacientes. Se evaluaron variables radiográficas de alineación, como ángulos alfa y beta, centro de rotación astragalino y el porcentaje de cobertura posterior de la tibia en el posoperatorio inmediato y a los 2 años. Las variables de evaluación clínica fueron: la escala analógica visual y la escala de la AOFAS, y el cuestionario SF-36 para evaluar la calidad de vida al final del seguimiento. Resultados: La etiología más frecuente de la artrosis fue la postraumática (67,7%). En el posoperatorio inmediato, el ángulo alfa promedio fue de 88,7° (rango 82-92,6; DE ± 2,61); el ángulo beta, de 84,46° (rango 78,62-91,40; DE ± 3,59). La alineación del componente tibial en el plano frontal fue neutra en 25 pacientes (80,6%), en valgo en 6 (19,4%) y en varo (0%). A los 2 años de seguimiento, el 96% tenía calcificacionesheterotópicas. Mejoraron los puntajes en la escala de la AOFAS (preoperatorio/posoperatorio: 31,90/80,94) y en la escala analógica visual (preoperatorio/posoperatorio: 8,7/1,97) (p <0,05). Conclusiones: No se halló una relación entre calcificaciones heterotópicas y peores resultados funcionales ni de dolor, excepto en los parámetros de calidad de vida (SF-36), como el rol físico, la limitación emocional y la percepción de la salud general, que empeoraron a medida que aumentó el grado de calcificacionesalrededor de la prótesis.

97 HINTEGRA ankle prostheses: Results and survival at more than 5 years' follow-up

BACKGROUND

In Europe, fixed-bearing implants predominate again in total ankle replacement (TAR). The present single-center single-surgeon study assesses the Hintegra® mobile-bearing implant (NEWDEAL).

METHODS

Between November 2008 and November 2015, 97 Hintegra® were implanted in 94 patients: mean age, 62.4±10.9 years (26-83); 59% (57/97) male; normal mean body-mass index (BMI), 27.5 ± 4.3 kg/m². Indications mainly comprised posttraumatic (40.2%), instability (29.9%) and primary osteoarthritis (16.5%). 17.5% of patients had prior surgery during the previous 6 months (9 fusions, 8 ligament reconstructions, and 4 osteotomies); in 59.8%, other procedures were associated to TAR. Functional, clinical and radiological follow-up was conducted at 1 year, 2 years and last follow-up (>5 years).

RESULTS

Ninety-four TARs were analyzed at a mean 81 ± 21.6 months (19-124). Revision-free survival was 76% (95% confidence interval (95%CI): 0.66-0.8), and explantation-free survival 92% (95%CI: 0.85-1) with 10 cases of curettage and 5 explantations. Mean AOFAS score improved from 41.8 ± 12.5 (21-69) to 77.5 ± 16.5 (24-100) up (p < 0.001); 75% of patients had no or only mild pain (p < 0.001). Clinical ranges of motion were 8.0 ± 7.1° dorsiflexion (p < 0.001) and 35.1 ± 9.4° plantar flexion (preoperatively, 34.1 ± 7.9°) (p = 0.71). Radiologically, tibial components were well-positioned; 87% of talar components were well-centered. Global ankle range of motion was 23.5 ± 10.2° (5-48) (p = 0.17). 54.6% of TARs showed posterior tibial calcification at follow-up. Risk of severe cyst (>1 cm) on CT was 36% (95%CI: 23-47) at a mean 77 ± 21.9 months (18-123).

CONCLUSION

Hintegra® TAR incurred a low risk of revision, and is a reliable option for ankle osteoarthritis.

LEVEL OF EVIDENCE

IV.

Corin ankle arthroplasty: Case-series

BACKGROUND

Total Ankle Arthroplasty (TAA) is complex and can bring a wide variety of complications. Implant revision rates can vary from 4% to 8% in 5 years. Recent publications have shown good results in the short and intermediate follow-up and high patient satisfaction. The pre- and postoperative evaluation of these patients should include physical examination and objective radiographic measurements, which may have predictive value for implant failures and survivorship. In this paper we will present the results obtained with 29 patients treated with the Zennith (Corin Group, UK) total ankle prosthesis in Brazil.

METHODS

This paper presents the results obtained with 29 patients treated with the Corin-Zennith prosthesis in three tertiary hospitals in Brazil, with an average follow-up of 5 years. The patients were submitted to clinical and radiographic evaluation. There were seventeen women and twelve men, ranging in age from 35 to 76 years, who were submitted to surgical treatment between January 16, 2013 and May 5, 2017.

RESULTS

Seven patients (24%) presented cysts, being 4 (13.7%) tibial cysts and 3 (10.3%) tibial and talar cysts. Six patients (20.6%) presented talar subsidence and 3 (10.3%) presented tibial subsidence. Three patients (10.3%) presented component wear. VAS reduced and AOFAS and ROM increased in the post-operative period. The development of Cysts was associated with the theta angle and the difference in LTS (between the post and preoperative period) was associated with tibial subsidence. The complications rate was 44.8%, the revision rate was 6.9% and the survivorship rate was 93.1%.

CONCLUSION

The Corin-Zennith prosthesis demonstrated to be a safe implant for improving functional parameters. Functional outcomes were not influenced for most commonly measured radiographic parameters. Further studies are needed to better understand these associations.

Long-Term Survival of HINTEGRA Total Ankle Replacement in 683 Patients: A Concise 20-Year Follow-up of a Previous Report

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

Heterotopic Ossification in Total Ankle Arthroplasty: Case Series and Systematic Review

Heterotopic ossification after total ankle arthroplasty (TAA) is a known sequela and has been reported to contribute to reduced range of motion and poor functional outcomes. However, conflicting results have been reported in the literature. The present study documents the incidence of heterotopic ossification for a novel fourth-generation fixed-bearing 2-component prosthesis and reports a systematic review of the literature. We reviewed the incidence and functional outcome of consecutively enrolled patients who underwent primary Infinity TAA between 2013 and 2015 in a prospective observational study. Preoperative and postoperative radiographic and functional outcome data were collected. A systematic review was also conducted investigating all published studies between 1998 and 2018 reporting the incidence of heterotopic ossification after TAA. The incidence of heterotopic ossification was 70.5% in the 61 patients who underwent primary TAA in the case series. There was no association between heterotopic ossification and American Orthopaedic Foot and Ankle Society (AOFAS) score, foot function index (FFI), visual analogue scale (VAS), and ankle osteoarthritis scale (AOS). Sixteen studies on 1339 TAA implants were included. The overall incidence of heterotopic ossification after TAA was 66.0% at average 3.6 years (range 22.2% to 100%). Four studies (299 ankles) did not address functional outcomes. Eleven studies (960 ankles) reported no association between heterotopic ossification and functional outcomes. One study (80 ankles) reported a statistically significant difference in range of motion (7°) and AOFAS score (7 points). In conclusion, although the incidence of heterotopic ossification after TAA is considerable, there is insufficient literature to suggest that heterotopic ossification after TAA impacts range of motion or functional outcome.

Anterior placement of the talar component in total ankle arthroplasty: A risk factor for talar component subsidence

BACKGROUND

Component subsidence is considered as a cause of revision surgery. The talar component subsidence may be a risk factor for revision surgery; however, there are no reports regarding talar component placement and subsidence amount following total ankle arthroplasty (TAA). We therefore investigated the relationship between talar component placement and subsidence amount.

METHODS

Fifty-two ankles from 49 patients (age: 71 years [range 62-83], 13 male/ 36 female), who underwent TAA with mean follow-up of 36 months (range 12-83), were included. The subjects were divided into two groups based on talar component placement: anterior placement (n = 20, group A) and posterior placement (n = 32, group P) using weight-bearing lateral plain radiographs. The amount of the talar component subsidence and clinical outcomes, which included the Japanese Society for Surgery of the Foot (JSSF) scale, range of the motion (ROM) and the revision rate, were compared between the groups.

RESULTS

Talar component subsidence was significantly higher in group A (2.1 ± 2.0 mm) than in group P (0.6 ± 1.4 mm, P = .017). There was no significant difference in the JSSF scale and ROM between group A and group P. The revision rate was 10.0% in group A and 6.3% in group P, albeit not statistically significant.

CONCLUSION

Greater talar component subsidence was observed when the talar component was placed more anteriorly, suggesting that anterior placement of the talar component may need to be avoided during the surgery in order to minimize the postoperative talar component subsidence.

Positive and negative factors for the treatment outcomes following total ankle arthroplasty? A systematic review

BACKGROUND

Patient selection, surgeon's experience and implant design play an integral role and affect the treatment outcomes of total ankle arthroplasty (TAA). The aims of this study were to investigate the positive and negative attributes that correlate with different clinical and radiographic outcomes.

METHODS

Eight-nine studies matched the inclusion criteria: (1) studies of primary TAA with uncemented prosthesis; (2) mean follow-up of no less than 2-year; (3) reports of clinical and radiographic outcomes, and exclusion criteria: (1) non-English study; (2) more than one type of prosthesis without separated data; (3) kin studies with shorter follow-up or smaller cohort. Age, etiology, preoperative deformity, surgeon's experience, follow-up duration and prosthetic type were studied with respect to different outcomes by mixed-effects logistic regression analysis.

RESULTS

Patients factor: older patients reported less pain or stiffness and demonstrated less radiographic loosening which did not require additional surgical intervention. More traumatic arthritis experienced adjacent joints degeneration after TAA. Surgeon factor: less experienced surgeons had more intraoperative complications. Lack of experience for complications management without implant retrieval during early period might result in more revisions or fusion was done. Prosthetic factor: updated instrumentation decreased malalignment. If the polyethylene (PE) insert was significantly narrower than the metal components more implant instability and subsequent severe particulate wear was seen. Designs with flat-on-flat articulation and ridge at the center of the talar component associated with more PE fracture. Minimal bone resection reduced postoperative fractures. A flat cut of the tibial component and a flat undersurface with press-fit by two screws or pegs of the talar component demonstrated less postoperative fractures, whereas a syndesmosis fusion and a small triangular shape with one central fin of the talar component experienced more loosening which did not require additional surgery. Anatomic conical shape of the talar component seemed to reduce adjacent joint degeneration. Finally, fewer failures were found in patients who received HINTEGRA and Salto Talaris.

CONCLUSIONS

Based on our investigation, some positive and negative factors for different clinical and radiographic outcomes were found, which should be taken into consideration in clinical practice and ankle implant design.

Clinical Outcomes of Total Ankle Arthroplasty With Total Talar Prosthesis

BACKGROUND

Total ankle arthroplasty (TAA) has been developed to treat patients with end-stage ankle osteoarthritis (OA). However, there is often difficulty in treating complicated pathologies such as ankle OA with subtalar joint OA and severe talar collapse. Therefore, this study aimed to explore the short-term results and complications of TAA with total talar prosthesis, known as combined TAA, as the new techniques to treat such complicated pathology.

METHODS

We examined postoperative results including ankle range of motion, Japanese Society for Surgery of the Foot (JSSF) scale, and complications. There were 22 patients (15 women), with mean follow-up of 34.9 (range, 24-53 months), and the mean age was 72 (range, 62-80) years. The main indications for combined TAA included osteoarthritis (18 patients), rheumatoid arthritis (3 patients), and talar osteonecrosis with osteoarthritis (one patient).

RESULTS

The mean range of motion improved from 4.0 to 14.4 degrees in dorsiflexion and from 23.8 to 32.0 degrees in plantarflexion. The JSSF scale improved from 50.5 to 91.5 points. Prolonged wound healing occurred in 3 patients, and medial malleolus fracture occurred in 4 patients.

CONCLUSION

Combined TAA was a reliable procedure for the treatment of not only ankle OA following avascular necrosis of talus but also of degeneration of both ankle and subtalar joints.

LEVEL OF EVIDENCE

Level IV, case series.

Peri-prosthetic bone cysts after total ankle replacement. A systematic review and meta-analysis

BACKGROUND

Periprosthetic cystic osteolysis is a well-known complication of total ankle replacement. Several theories have been proposed for its aetiology, based on individual biomechanical, radiological, histopathology and outcome studies.

METHODS

Studies that met predefined inclusion/exclusion criteria were analysed to identify literature describing the presence of peri-prosthetic ankle cystic osteolysis. Quantitative data from the selected articles were combined and statistically tested in order to analyse possible relations between ankle peri-prosthetic bone cysts and specific implant characteristics.

RESULTS

Twenty-one articles were elected, totalizing 2430 total ankle replacements, where 430 developed peri-prosthetic cystic osteolysis. A statistically significant association (P<.001) was found between the presence of bone cysts and non-anatomic implant configuration, hydroxyapatite-coating, mobile-bearing and non tibial-stemmed implants. No significant association existed between the type of constraining and the presence of cysts (P>.05).

CONCLUSIONS

Non-anatomic, mobile-bearing, hydroxyapatite-coated and non tibial-stemmed total ankle replacements are positively associated with more periprosthetic bone cysts.

Comparison of 25 ankle arthrodeses and 25 replacements at 67 months' follow-up

INTRODUCTION

In the treatment of osteoarthritis of the ankle, controversy persists between advocates of arthrodesis and of joint replacement.

HYPOTHESIS

Results of total ankle replacement (TAR) are equivalent to those of ankle arthrodesis (AA).

MATERIAL AND METHODS

A single-center continuous retrospective series included 50 patients (25 TAR, 25 AA) operated on by a single surgeon. TAR used the standard Salto^® mobile-bearing prosthesis, and arthrodesis used screws or plates. Results were assessed clinically on AOFAS score, visual analog scale (VAS) and satisfaction questionnaire, and radiologically on X-ray and CT. Survivorship in the 2 procedures was estimated on the Kaplan Meier method.

RESULTS

At a mean 67 months' follow-up (range, 40-105 months), mean AOFAS and VAS scores were significantly better in the AA group (74.1 and 1.9, respectively) than in the TAR group (67 and 3.5, respectively) (p<0.001). In the AA group, 80% of patients were satisfied or very satisfied, compared to 64% after TAR. Five-year survival without revision for non-union (AA) or implant removal (TAR) was similar between groups: AA, 96%; TAR, 90% (p=0.72). In contrast, survival with no revision procedures was significantly better with AA (96%) than TAR (75%) (p=0.03).

DISCUSSION

At 5 years, surgical revision rates were significantly greater than after standard Salto^® mobile-bearing TAR than for arthrodesis, notably due to onset of cysts; we therefore decided to abandon this implant.

LEVEL OF EVIDENCE

IV, comparative retrospective study.

Ankle arthroplasty: A review and summary of results from joint registries and recent studies

Total ankle arthroplasty offers a reasonable alternative to ankle arthrodesis in carefully selected patients.

It is debatable whether rheumatoid arthritis patients have better outcomes compared with those who have ankle arthroplasty for either primary osteoarthritis or post-traumatic arthritis.

Aseptic loosening and infection are the most common complications requiring revision.

It is worth noting that some of the best survival rates are seen in the surgeon-designer case series.

The uncemented mobile or fixed bearing prostheses have better outcomes compared with their older counterparts.

There is no convincing evidence to suggest superiority of one design over another among the currently available prostheses.

Ankle arthroplasty surgery has a steep learning curve; the prosthesis choice should be driven by the surgeon’s training and experience.

Cite this article: EFORT Open Rev 2018;3:391-397. DOI: 10.1302/2058-5241.3.170029

Heterotopic ossification after total ankle replacement: The role of prosthesis alignment

BACKGROUND

The aetiology of heterotopic ossifications (HO) after total ankle arthroplasty (TAR) remains controversial. The aim of the study was to evaluate the prevalence and localisation of HO and the effect of alignment.

METHODS

88 TARs with a series of radiological controls and follow-up of 36 months were evaluated. Frontal and sagittal alignment parameters (alfa and beta angle defined by Hintermann) and tibial coverage were evaluated.

RESULTS

The prevalence and grading of HO increased over time, mostly in the posterior gutter. Varus alignment correlated with HO increase in the ventral and lateral gutters the first year. A dorsally located rotational centre correlated with total HO growth and HO in the posterior gutter. These correlations were not detected after 3 years, as HO were seen in all prostheses, regardless of alignment.

CONCLUSIONS

HO grow over time with a prevalence up to 100% after 3 years. TAR alignment correlates with gutter-specific HO formation within the first year.

Sagittal tibiotalar translation and clinical outcomes in mobile and fixed-bearing total ankle replacement

BACKGROUND

Sagittal implant malalignment after total ankle replacement (TAR) has been considered to be a possible cause for premature implant failure. In a prior study, the change over time of the tibiotalar ratio (T-T ratio), which is the ratio between the posterior longitudinal talar length and the full longitudinal talar length, was assessed in 66 TARs where an unconstrained, mobile-bearing implant was implanted. The analysis documented an increase in the T-T ratio between 2 and 6 months post-surgery (on average from 34.6% to 37.2%). We hypothesized that this change might have been related to the presence of a mobile-bearing insert. In order to test our hypothesis, we designed a study to compare the translation of the talus in TARs performed with an unconstrained, mobile-bearing implant (designated the "Mobile ankle") and those performed with a semi-constrained, fixed-bearing implant (designated the "Fixed ankle").

METHODS

The study included 71 consecutive patients (71 ankles) who underwent TAR with the Mobile ankle and 24 consecutive patients (24 ankles) who received the Fixed ankle from May 2011 to December 2014. Patients were assessed clinically and radiologically preoperatively (T₀), at 6 months (T₂) and 12 months (T₃) post-surgery. There was also a radiological assessment at 2 months post-surgery (T₁).

RESULTS

The comparison of the T-T ratio between the two implant groups and over time indicated an interaction between time and group, therefore the changes of the T-T ratio over time were affected by the implant type factor (P<0.001). The changes of the postoperative T-T ratio over time were not significant in the Fixed ankle group (35.7±6.7% at T₁, T₂, and T₃; P=1.0 for each pairwise comparison). In the Mobile ankle group, the T-T ratio at 2 months (34.4±5.5%) was significantly different to the T-T ratio at 6 months (37.0±5.8%; P<0.001; i.e. there was a significant posterior translation of the talus). The AOFAS score increased from preop to 12 months post-surgery in both the Mobile ankle (72.7±12.8 at 12 months; P<0.001) and the Fixed ankle (85.0±9.7 at 12 months; P<0.001).

CONCLUSION

The significant posterior translation of the talus from 2 to 6 months documented only in the Mobile ankle group may have been associated with the presence of the mobile bearing interface.

A Prospective Study of Four Total Ankle Arthroplasty Implants by Non-Designer Investigators

BACKGROUND

There are several types of prostheses available to surgeons when performing a total ankle arthroplasty (TAA). The main objective of this study was to summarize the clinical and functional outcomes of 4 TAA prostheses: the Hintegra implant (Integra LifeSciences), the Agility implant (DePuy), the Mobility implant (DePuy), and the Scandinavian Total Ankle Replacement (STAR) implant (Small Bone Innovations [SBi]).

METHODS

Patients were prospectively recruited. A total of 451 TAAs with a mean follow-up (and standard deviation) of 4.5 ± 2.0 years were included. Patients were assessed annually and completed self-reported outcome measures at these visits. Complications and revisions were reported at the time of incident. Mean improvements are reported by prosthesis. Linear mixed-effects models were used to obtain adjusted comparisons of scores across prostheses. Survivorship curves were generated by prosthesis and type of complication.

RESULTS

Mean improvement in the Ankle Osteoarthritis Scale (AOS) total score was less among patients with the Mobility implant (19.5; 95% confidence interval [CI], 15 to 24) than it was among patients with the Agility implant (29.1; 95% CI, 24 to 34), Hintegra implant (29.7; 95% CI, 27 to 33), and STAR implant (28.5; 95% CI, 23 to 34). Patients in the Mobility group also had less mean improvement in the AOS pain score (21.3; 95% CI, 17 to 26) compared with patients in the Hintegra (29.0; 95% CI, 26 to 32), Agility (29.8; 95% CI, 25 to 35), and STAR (29.1; 95% CI, 23 to 35) groups. The Mobility group also had less mean improvement in the AOS disability score (17.3; 95% CI, 12 to 23) compared with the Hintegra (30.4; 95% CI, 27 to 34), Agility (28.8; 95% CI, 23 to 34), and STAR (27.8; 95% CI, 21 to 34) groups. Survival results among the 4 prostheses are reported.

CONCLUSIONS

This study demonstrated acceptable outcomes of 4 modern TAA prostheses. Outcome results from patient-reported scores were comparable between at least 3 of the 4 prostheses (the Hintegra, STAR, and Agility implants). The rates of complications and revisions found in this study are within the limits reported in the literature for similar prostheses and methods of reporting.

LEVEL OF EVIDENCE

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

Anterior Approach Total Ankle Arthroplasty: Superficial Peroneal Nerve Branches at Risk

In ankle arthroplasty, little attention has been given to intraoperative nerve injury and its postoperative sequelae. The aim of the present anatomic study was to determine the relationship of the superficial peroneal nerve to the standard anterior approach for total ankle arthroplasty. The superficial peroneal nerve was dissected in 10 below-the-knee cadaver specimens. The medial and intermediate dorsal cutaneous branches were identified. A needle was placed at the ankle joint. The following measurements were recorded: bifurcation into the medial and intermediate dorsal cutaneous branches, reference needle to the branches of the medial and intermediate superficial peroneal nerve, and the crossing branches of the medial dorsal cutaneous nerve. Two specimens (20%) had a medial dorsal cutaneous branch cross from medially to laterally. Eight specimens (80%) had a crossing branch of the medial dorsal cutaneous branch within 5 cm of the incision. No intermediate dorsal cutaneous branches were within the incision. The results from the present cadaver study suggest that during an anterior ankle approach, aberrant branches of the superficial peroneal nerve could require transection in 20% of patients at the joint level and ≤80% of patients with distal extension >35 mm from the ankle joint. The risk of injury to branches of the superficial peroneal nerve is substantial. The risk of nerve injury can be decreased with meticulous operative technique, smaller incisions, and the avoidance of aggressive retraction.

Comparison of the outcomes between two 3-component total ankle implants

BACKGROUND

Total ankle arthroplasty (TAA) with the use of third generation implants has demonstrated favorable clinical results and improved survival. However, few studies have compared the different types of implants. The purpose of this study was to perform a retrospective evaluation of patient outcomes and complications by comparing TAA procedures performed with HINTEGRA versus MOBILITY systems.

METHODS

Fifty-two consecutively enrolled patients (28 men and 24 women; mean age 64.8 years) underwent TAA using HINTEGRA (21 ankles) or MOBILITY (33 ankles) between September 2004 and July 2012. Visual analog scale (VAS) pain scores and the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores were determined at each follow-up visit. The radiographs were reviewed to assess component positioning, radiolucency, heterotopic ossification, and other factors. The mean follow-up period was 28.3 months in the HINTEGRA group and 32.5 months in the MOBILITY group.

RESULTS

VAS decreased from 8.3 to 2.0 for the HINTEGRA group and from 7.9 to 2.7 for the MOBILITY group. The AOFAS score increased from 43.8 to 87.3 for the HINTEGRA group and from 46.6 to 83.7 for the MOBILITY group. Intra- and postoperative malleolar fractures were not noted in the HINTEGRA group, whereas 5 ankles (15.2%) in the MOBILITY group sustained this injury (P = .144). Ankle impingement syndrome was noted in 8 ankles (38.1%) in the HINTEGRA group and 3 (9.1%) in the MOBILITY group (P = .015). However, no significant differences in postoperative osteolysis and neuralgia were noted between the groups.

CONCLUSIONS

Both implants exhibited favorable clinical outcome without significant differences. However, in terms of complications, ankle impingement syndrome was significantly more common in the HINTEGRA group, while intraoperative malleolar fracture was observed only in the MOBILITY group.

LEVEL OF EVIDENCE

Level III, comparative series.

Intermediate-term Results of Mobile-bearing Total Ankle Replacement

BACKGROUND

The literature analyzing total ankle replacement (TAR) results should be critically interpreted because studies made by the design surgeons are potentially subject to bias. European nondesigner surgeon studies reviewing the HINTEGRA TAR system are scarce in the literature. The present study is a European nondesigner surgeon study reviewing a consecutive series of 50 HINTEGRA TAR systems with a minimum follow-up of 2 years, focusing on clinical and radiographic outcomes.

METHODS

Fifty primary TAR procedures were performed between February 2008 and January 2012 by a single surgeon. Every patient underwent a standardized clinical and radiographic follow-up at 6 weeks, 3 and 6 months, and 1 year postoperatively and annually thereafter. The mean time to final follow-up was 45 months.

RESULTS

The mean American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale score significantly increased from 43.5 preoperatively to 83.8 postoperatively. Clinical range of motion of the ankle also improved from 23.3 degrees preoperatively to 28.3 degrees postoperatively. In 70% of the TAR procedures, the talar component was positioned anteriorly with respect to the tibial axis. Radiological evidence of osteolysis was identified in 24 ankles. The failure rate in the present series was 10%, which was defined as having major revision surgery within 4 years.

CONCLUSION

The survival of the first 50 HINTEGRA TAR systems in this series was satisfactory from clinical and radiological points of view. However, the incidence of asymptomatic periprosthetic osteolytic lesions was quite high (24 ankles).

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Therapeutic effects of segmental resection and decompression combined with joint prosthesis on continuous knee osteoarthritis

OBJECTIVE

To observe the therapeutic effects of segmental resection and decompression combined with joint prosthesis on continuous knee osteoarthritis (OA).

METHODS

A total of 130 patients with knee OA were selected and randomly divided into an observation group and a control group (n=65). The control group was treated by segmental resection in combination with joint prosthesis, and the observation group was treated by segmental resection and decompression combined with joint prosthesis. They were followed-up for three months.

RESULTS

All patients underwent successful surgeries during which no severe complications occurred. During the follow-up period, the overall effective rates of the observation group and the control group were 93.8% and 78.5% respectively, which were not statistically significantly different (p < 0.05). The observation group was significantly less prone to patellar instability, infection and deep vein thrombosis compared with the control group (P < 0.05). On the same day after surgery, the knee joint scores and functional scores of the two groups were similar, which evidently increased three months later, with significant intra-group and inter-group differences (p < 0.05).

CONCLUSION

Combining segmental resection and decompression with joint prosthesis gave rise to satisfactory short-term prognosis by effectively improving the flexion and extension of injured knee and by decreasing complications, thus being worthy of promotion in clinical practice.

The impact of diabetes on the short- to mid-term outcome of total ankle replacement

We compared the clinical and radiographic results of total ankle replacement (TAR) performed in non-diabetic and diabetic patients. We identified 173 patients who underwent unilateral TAR between 2004 and 2011 with a minimum of two years’ follow-up. There were 88 male (50.9%) and 85 female (49.1%) patients with a mean age of 66 years (sd 7.9, 43 to 84). There were 43 diabetic patients, including 25 with controlled diabetes and 18 with uncontrolled diabetes, and 130 non-diabetic patients. The clinical data which were analysed included the Ankle Osteoarthritis Scale (AOS) and the American Orthopaedic Foot and Ankle Society (AOFAS) scores, as well the incidence of peri-operative complications.

The mean AOS and AOFAS scores were significantly better in the non-diabetic group (p = 0.018 and p = 0.038, respectively). In all, nine TARs (21%) in the diabetic group had clinical failure at a mean follow-up of five years (24 to 109), which was significantly higher than the rate of failure of 15 (11.6%) in the non-diabetic group (p = 0.004). The uncontrolled diabetic subgroup had a significantly poorer outcome than the non-diabetic group (p = 0.02), and a higher rate of delayed wound healing.

The incidence of early-onset osteolysis was higher in the diabetic group than in the non-diabetic group (p = 0.02). These results suggest that diabetes mellitus, especially with poor glycaemic control, negatively affects the short- to mid-term outcome after TAR.

Cite this article: Bone Joint J 2014;96-B:1674–80.