Arthroscopic Subtalar Arthrodesis: Does the Type of Fixation Modify Outcomes?

Factors influencing successful bone union of isolated subtalar arthrodesis for posttraumatic subtalar arthritis: a multicenter case series

BACKGROUND

The purpose of this study was to find the factors influencing successful bone union for isolated subtalar arthrodesis in posttraumatic subtalar arthritis following calcaneal fracture.

MATERIAL AND METHODS

We retrospectively analyzed the rate of successful bone union of 119 cases of isolated subtalar arthrodesis for posttraumatic subtalar arthritis performed at five university hospitals between January 2010 and December 2019. Multivariate logistic regression analysis was used to find the factors associated with successful bone union. Successful bone union was defined as resolution of hindfoot pain with the presence of osseous trabecular bridging involving more than 50% of the posterior facet within 6 months postoperatively.

RESULTS

There were 77 (64.7%) cases of successful bone union, 11 (9.2%) cases of delayed union, 8 (6.7%) cases of questionable union, and 23 (19.3%) cases of nonunion. Use of fully threaded screws was 5.90 times [odds ratio (OR) = 5.90, 95% confidence interval (CI) = 1.42-24.49, p = 0.02] more likely to achieve successful bone union compared to the use of partially threaded screws. Use of two parallel screws or the two divergent screws were 3.71 times (OR = 3.71, 95% CI = 1.05-13.14, p = 0.04) and 4.65 times (OR = 4.65, 95% CI = 1.23-17.53, p = 0.02) more likely to achieve successful bone union compared to the use of a single screw. Use of cancellous autograft or structural autograft was 4.72 times (OR = 4.72, 95% CI = 1.17-19.06, p = 0.03) and 7.12 times (OR = 7.12, 95% CI = 1.46-34.68, p = 0.02) more likely to achieve successful bone union compared to no graft use.

CONCLUSION

Use of fully threaded screws, autograft, and two screws compared to a single screw were the factors associated with successful bone union within six postoperative months after subtalar arthrodesis for the posttraumatic arthritis.

Modified Posterior 2-Portal Technique of Arthroscopic Subtalar Joint Arthrodesis: Improved Pain and Functional Outcome at Mean 15 Months Follow-up-A Case Series

INTRODUCTION

Posterior arthroscopic subtalar joint arthrodesis (PASTA) via a posterior 2-portal technique has been described. We modified the surgical technique of creating the portals in the plane of the posterior facet (under fluoroscopy guidance) to enhance the ease of access to the joint, easier and complete removal of articular cartilage along with maintaining the heel height.

METHODS

Patients of post-traumatic subtalar joint arthritis, treated by PASTA during 2016 till 2019 were included in the study. Exclusion criteria: significant height collapse of calcaneum, lateral blow out or heel widening. The confirmation of subtalar joint as the source of pain was done by injection of local anaesthetic inside the joint under the image intensifier, bringing immediate pain relief. The primary outcome variables assessed were the pain and functional scores, assessed using visual analogue scale and AOFAS (American Orthopaedic Foot and Ankle Society) score, respectively.

RESULTS

The total of 16 patients (7 males, 9 females) was included. The average age was 40.68 years (23-58 years). The underlying pathology in all patients was post-traumatic subtalar arthritis secondary to calcaneus fracture malunion in 8 patients (50%), talus fracture malunion in 4 (25%) and ligament injury in 2 patients (12.5%). No bone grafting was done. The mean duration of follow-up was 15.6 months (9-24 months). There was a statistically significant improvement (p < 0.001) in mean VAS score at follow up (2; range 0-4) as compared to the mean preoperative score (7; range 6-9). The AOFAS score also improved significantly (p < 0.001) at the follow up (mean 79; range 68-89) as compared to the preoperative score (mean 18; range 10-25).

CONCLUSION

The posterior arthroscopic fusion of subtalar joint gives good results in terms of pain relief and functional scores when done for carefully selected patients of subtalar joint arthritis. Our slight modification of the original technique improves the ease of removing cartilage from subtalar joint with minimal height loss; thus, precluding any need for bone graft. It also makes the instrument movement easier inside the joint.

Arthroscopic Subtalar Joint Arthrodesis: Topical Review

BACKGROUND

Advances in foot and ankle arthroscopy over the last 2 decades have allowed for subtalar joint arthrodesis to be performed arthroscopically. The potential advantages of the arthroscopic technique include higher fusion rates, lower complications, reduced perioperative morbidity, and accelerated rehabilitation. Arthroscopic arthrodesis may, however, not be appropriate in the setting of complex deformity correction or the need for other open procedures.

METHODS

Surgical techniques of arthroscopic subtalar joint arthrodesis are described. Outcomes and complications associated with these procedures are presented, based on a comprehensive literature review. Thirteen Level IV studies of moderate quality were included.

RESULTS AND CONCLUSION

Excellent arthrodesis union rates were achieved (average 96%, range 86%-100%), at a weighted average union time of 8.8 weeks (95% confidence interval 7.9-9.7). The overall complication rate was 21% (87/415 feet; range 10%-36.4%). Metal irritation was the most common complication (11.2%), followed by nerve injury (4.2%) and infection (0.9%). Similar fusion rates have been reported when comparing arthroscopic and open arthrodesis. Complication rates are also similar, excerpt for infection, which may be lower with arthroscopy. Three different approaches were used to access the subtalar joint with similar union and complication rates. There was no evidence that the use of bone graft or more than 1 screw improved outcomes. The superiority of arthroscopic subtalar fusion over open techniques cannot be demonstrated by the available studies.

LEVEL OF EVIDENCE

Level IV, case series.

Outcomes of Posterior Arthroscopic Subtalar Arthrodesis for Medial Facet Talocalcaneal Coalition

BACKGROUND

Medial facet talocalcaneal coalition can be a painful condition. This study aimed to determine clinical and radiographic outcomes of posterior arthroscopic subtalar arthrodesis (PASTA) for adult patients presenting with symptomatic medial facet talocalcaneal coalition and normal hindfoot alignment, with a minimal follow-up of 18 months.

METHODS

Between June 2017 and July 2019, this procedure was performed on 8 feet (8 patients; mean age, 55 [42-70] years; mean BMI, 29.8 [24.4-45.0] kg/m²). Clinical assessment was performed using Visual Analog Scale for Pain (VAS-P), Foot and Ankle Outcome Score (FAOS) and the 36-Item Short-Form Health Survey (SF-36). Patient satisfaction was assessed at the last available follow-up as "very satisfied", "satisfied" or "unsatisfied". Radiographic analysis was performed using plain radiography, computed tomography (CT) scan and magnetic resonance imaging (MRI). The primary outcome was to determine both clinical and radiographic outcomes.

RESULTS

The mean follow-up was 25.1 (18.2-34.2) months. The authors found statistically significant improvement on all clinical scores (VASP-P, FAOS and SF-36). They registered 6 "very satisfied" patients, 2 "satisfied" patients and no "unsatisfied" patient. Fusion of the subtalar joint was observed in all patients by 12 weeks and in 5 of them as soon as 8 weeks postoperatively (mean, 9.5 [8-12] weeks). There were no cases of delayed fusion or nonunion of the subtalar joint, superficial or deep infection, neurovascular damage, thromboembolic event, screw breakage, need for hardware removal or revision surgery.

CONCLUSION

This study found that PASTA is a safe and reliable technique for adult patients presenting with symptomatic medial facet talocalcaneal coalition and normal hindfoot alignment, demonstrating and maintaining clinical improvement at an average follow-up of 2 years.

LEVEL OF EVIDENCE

Level IV, case series.

Subtalar arthrodesis using a single compression screw: a comparison of results between anterograde and retrograde screwing

INTRODUCTION

The primary objective of this study was to compare the radiological and clinical results of anterograde and retrograde screwing in subtalar arthrodesis using a single compression screw. The secondary objective was to evaluate the subjective results and consolidation of this procedure. The hypotheses were that isolated screw fixation was sufficient to achieve good consolidation and that there was no difference between the two techniques with a similar rate of bone fusion.

METHODS

This is a monocentric, retrospective, radio-clinical study based on 99 patients (101 feet), 58 males and 41 females, with an average age of 64 years. The main aetiology was post-traumatic osteoarthritis, which represented 51% of cases. Two groups were formed: group A (52 feet) consisting of fixed arthrodesis with ascending (retrograde) screwing and group D (49 feet) consisting of fixed arthrodesis with descending (anterograde) screwing. The two groups were statistically comparable in terms of demographic data as well as aetiologies and comorbidities. Arthrodeses which were not fused at 6 months were reassessed at one year and in the event of any radio-clinical doubt regarding consolidation, an additional CT scan was prescribed. Average post-operative follow-up was 11 ± 5 years (2-27 years).

RESULTS

Ninety-two arthrodeses (93%) were fused at one year and 9 were considered to be in non-union, 5 (9.8%) in group A, and 4 (8.3%) in group D. We recorded 30 complications, 22 of which were due to a conflict with the screw head, 18 (34.5%) in group A and 4 (8.3%) in group D (p = 0.03). Conflict between the screw head and the heel led to the removal of the screw after consolidation of the arthrodesis. The clinical results were evaluated using Odom's criteria. Nine per cent of patients described their results as excellent, 29% as good, 51% as satisfactory and 11% found the result to be poor.

CONCLUSION

The fusion rate for isolated compression screw arthrodesis is good, and there is no difference between anterograde and retrograde screws. However, the discomfort caused by the screw head being insufficiently embedded in the retrograde group led to a non-negligible number of additional surgeries to remove the screw.

Isolated Arthroscopic-Assisted Subtalar Fusion: A Systematic Review

BACKGROUND

The subtalar joint has a complex anatomic function that includes inversion and eversion of the hindfoot, assisting in walking on uneven surfaces. Arthritis is the most common pathological condition affecting this joint and can require fusion. The surgery can be performed open or with arthroscopic assistance. This systematic review assesses articles written on the safety and efficacy of isolated arthroscopic subtalar fusion.

METHODS

Using MEDLINE and Embase, we systematically reviewed articles published before May 21, 2020.

RESULTS

Of 395 articles, 17 on a total of 395 patients (409 operations) were included in the review. The average duration of follow-up was 40.0 months (range, 3 to 105 months). Radiographic evidence of union was reported for 95.8% of cases at an average of 11.9 weeks (range, 6 to 56 weeks) postoperatively. Delayed union was reported in 1.0% of patients and nonunion, in 4.3% of patients. In the articles reporting patient satisfaction, including pain relief, 95.4% of patients had positive outcomes. Postoperative complications were reported in 64 patients (16.2%), including 37 (9.4%) with symptomatic implants, 11 (2.8%) with dysesthesia or neuropathic pain, and 3 (0.8%) with postoperative infection.

CONCLUSIONS

Arthroscopic subtalar fusion is a safe and effective alternative to open subtalar arthrodesis, with high patient satisfaction rates, high union rates at similar follow-up intervals, and low complication rates. The aim of future research should be to determine the ideal cases for this approach as well as the most efficient arthroscopic surgical technique and postoperative rehabilitation to optimize function and union as seen on radiographs.

LEVEL OF EVIDENCE

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

Common Pitfalls in Subtalar Joint Preparation for Arthrodesis via Sinus Tarsi Approach

This cadaveric study assessed factors that could lead to nonunions in subtalar joint arthrodesis. The purpose of this study was to assist surgeons in achieving sufficient joint preparation in hopes to achieve more frequent arthrodesis of the subtalar joint. We evaluated the influence of experience in regard to cartilage preparation of the joint. We also assessed which quadrants of the subtalar joint were more likely to have unprepared cartilage. The subtalar joints in 17 cadaveric limbs were prepared by 17 participants with differing levels of experience. After the cartilage was denuded, the percentage of unprepared cartilage in each subtalar joint was calculated. The medial quadrants were more likely to have unprepared surfaces. There was also a learning curve present with subtalar joint preparation, as seen by the significantly larger percentage of unprepared cartilage in cadavers prepared by first year residents.

Comparison of different bone graft with arthroscopy-assisted arthrodesis for the treatment of traumatic arthritis of the subtalar joint

AIM OF THE STUDY

To compare the clinical outcomes of traumatic arthritis of the subtalar joint treated by arthroscopy-assisted arthrodesis with autologous bone graft, allogenous bone graft, artifical bone graft, and no bone graft .

METHODS

Sixty-two patients (64 ft) with traumatic arthritis of subtalar joint were randomly divided into four groups. The cases treated with arthroscopy-assisted arthrodesis were analyzed retrospectively. The mean follow-up time was about 22 months (18-28 months) in each group. Clinical outcomes were assessed by the American Orthopaedic Foot and Ankle Society (AOFAS) score, Visual Analog Scale (VAS), and radiographic examination. The post-operative complications in each group were recorded respectively.

RESULTS

All operations were successful, without incision complications. The subtalar joint obtained full osseous fusion in each group. The average time of osseous fusion was about 12 weeks. There was no significant difference in the fusion time with each group (P = 0.991). The AOFAS and VAS scores in each group were improved significantly in the pre-operative vs post-operative evaluation (all P < 0.01). The average operation time in autologous bone graft group was 74.56 ± 11.45 min which significantly different from that of other groups(P < 0.01).

CONCLUSION

Similar clinical outcomes were achieved among each type of bone graft. Therefore, which types of bone graft or not may be not the most important for arthroscopy-assisted subtalar arthrodesis.

Do Patient Positioning and Portal Placement for Arthroscopic Subtalar Arthrodesis Matter?

Background

Arthroscopic subtalar arthrodesis was first described over 2 decades ago and originally performed in the lateral decubitus or supine position using anterolateral and posterolateral portals situated about the fibula. More recently, several authors have advocated for prone positioning utilizing posteromedial and posterolateral portals with an optional accessory lateral portal. To date, a comparison of these techniques has been limited.

Purpose

To determine the effect of patient positioning and portal placement on complication rates after arthroscopic subtalar arthrodesis.

Study Design

Systematic review; Level of evidence, 4.

Methods

A systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Patients were placed into 1 of 3 groups: the lateral group if they were positioned lateral or supine with lateral-based portals; the 2-portal prone group if they were positioned prone with posteromedial and posterolateral portals; or the 3-portal prone group if posteromedial, posterolateral, and accessory lateral portals were utilized in the prone position. Inverse variance-weighted fixed-effects models were used to evaluate pooled estimates.

Results

A total of 20 studies examining 484 feet in 468 patients with a mean follow-up of 36.1 months were included for analysis. Overall, 8 studies examined patients in the prone position with 2 posterior portals (n = 111; 22.9%), 7 articles evaluated lateral portals (n = 182; 37.6%), and 5 studies examined patients in the prone position with 3 portals (n = 191; 39.5%). The total complication rate was similar (P = .620) between the 2-portal prone (18.9%), 3-portal prone (17.8%), and lateral (17.6%) groups. There was no difference observed in the rate of complications secondary to portal placement (P ≥ .334), rate of painful hardware (P ≥ .497), and rate of repeat surgery (P ≥ .304). The 2-portal prone group had a significantly higher rate of nonunion than the lateral group (8.1% vs 1.1%, respectively; P = .020) but not the 3-portal prone group (5.8%; P = .198).

Conclusion

The current study demonstrated a higher rate of nonunion following arthroscopic subtalar arthrodesis with prone patient positioning using posteromedial and posterolateral portals without an accessory lateral portal.

Subtalar Fusion Preparation: What Are We Really Doing? A Cadaver Study

Introduction. The open, lateral sinus tarsi approach is the most commonly used technique for subtalar arthrodesis. In this cadaver study, we measured the maximum joint surface area that could be denuded of cartilage and subchondral bone through this approach. Methods. Nine fresh frozen above-knee specimens were used. The subtalar joint was accessed through a lateral incision from the fibular malleolus distally over the sinus tarsi area to the level of the calcaneocuboid joint. Cartilage was removed from the anterior, middle, and posterior facets of the calcaneus and talus using an osteotome and/or curette. ImageJ was used to calculate the surface areas of undenuded cartilage. Results. No specimens were 100% denuded of cartilage on all 6 measured surfaces. The greatest percentages of unprepared surface area remained on the middle facet of the talus (18.66%) and the middle facet of the calcaneus (14.51%). The anterior facet of the talus was 100% denuded in 6 specimens, while the middle and posterior facets were 100% denuded in 3 specimens. The anterior facet of the calcaneus was also 100% denuded in 6 specimens, while the middle and posterior facets were 100% denuded in 3 and 4 specimens, respectively. The average total unprepared surface area per specimen was 8.67%. Conclusion. The lateral sinus tarsi approach provides adequate denudation of cartilage of the subtalar joint in most cases. Total percentage of unprepared joint surface may range from approximately 2% to 18%. Future clinical studies are warranted to assess whether this technique results in optimal union rates. Levels of Evidence:V, Cadaveric Study.