Surgical Site Infections After Routine Syndesmotic Screw Removal: A Systematic Review

Risk factors associated with breakage of tibio-fibular syndesmotic screws

PURPOSE

This retrospective study aimed to investigate the factors associated with the breakage of tibio-fibular syndesmotic screws (SS).

METHODS

69 patients with unstable AO-Weber Type 44-B ankle fractures who underwent three cortex SS (3.5 mm ø) fixation were included. Patients were followed for at least one year (mean, 18.3 ± 7.6 months). At the final follow-up, patients with broken (Group I) and intact (Group II) SS were compared regarding age, gender, height, weight, body mass index, fracture type, SS length, location, and orientation. Multivariate logistic regression was used to identify the independent risk factors associated with SS breakage. The sensitivity, specificity, cut-off value, and area under the ROC curve were analyzed.

RESULTS

A stepwise backward logistic regression analysis revealed that age was the only independent predictor for SS breakage (OR = 0.938, 95% CI = 0.904-0.973, R2 = 0.270). ROC curve analysis demonstrated that patients younger than 36 years were associated with seven times increased risk of SS breakage [Odds ratio (95% CI), 7.042 (2.251-22.031)].

CONCLUSION

Age under 36 years was the only significant risk factor for SS breakage. The higher incidence of breakage of the syndesmotic screw can be informed to patients younger than 36.

Functional outcome of routine versus on-demand removal of the syndesmotic screw

Aims

The primary aim of this study was to present the mid-term follow-up of a multicentre randomized controlled trial (RCT) which compared the functional outcome following routine removal (RR) to the outcome following on-demand removal (ODR) of the syndesmotic screw (SS).

Methods

All patients included in the 'ROutine vs on DEmand removal Of the syndesmotic screw' (RODEO) trial received the Olerud-Molander Ankle Score (OMAS), American Orthopaedic Foot and Ankle Hindfoot Score (AOFAS), Foot and Ankle Outcome Score (FAOS), and EuroQol five-dimension questionnaire (EQ-5D). Out of the 152 patients, 109 (71.7%) completed the mid-term follow-up questionnaire and were included in this study (53 treated with RR and 56 with ODR). Median follow-up was 50 months (interquartile range 43.0 to 56.0) since the initial surgical treatment of the acute syndesmotic injury. The primary outcome of this study consisted of the OMAS scores of the two groups.

Results

The median OMAS score was 85.0 for patients treated with RR, and 90.0 for patients treated with ODR (p = 0.384), indicating no significant difference between ODR and RR. The secondary outcome measures included the AOFAS (88.0 in the RR group and 90.0 for ODR; p = 0.722), FAOS (87.5 in the RR group and 92.9 for ODR; p = 0.399), and EQ-5D (0.87 in the RR group and 0.96 for ODR; p = 0.092).

Conclusion

This study demonstrated no functional difference comparing ODR to RR in syndesmotic injuries at a four year follow-up period, which supports the results of the primary RODEO trial. ODR should be the standard practice after syndesmotic screw fixation.

Predictors of Hardware Removal in Orthopaedic Trauma Patients Undergoing Syndesmotic Ankle Fixation With Screws

Background

Indications for removal of syndesmotic screws are not fully elucidated. This study aimed to determine factors related to elective syndesmotic screw removal.

Methods

Patients who underwent fixation of ankle syndesmotic injuries were included. Screw removal was offered after a minimum of 12 weeks after surgery for pain, stiffness or patient desire to remove painful or broken hardware. Patient demographics, surgical data, distance of the syndesmotic screw from the joint, location of the screw at the physeal scar, and number of syndesmotic screws placed were collected for all patients. Bivariate and multivariate analyses were performed to determine the relationship between patient characteristics and screw removal and independent predictors of hardware removal.

Results

Of 160 patients, 60 patients (38%) with an average age of 36.1 (range: 18-84) years underwent elective syndesmotic screw removal at a mean of 7 (range, 3-47) months after initial fixation. The most common reason for screw removal (50/60 patients) was ankle stiffness and pain (83%). Patients who underwent screw removal were more likely to be younger (36.1 years ± 13.0 vs 46.6 years ± 18.2, P < .001) and have a lower ASA score (2 ± 0.8 vs 2.1 ± 0.7, P = .003) by bivariate analysis. Of patients who underwent screw removal, 21.7% (13/60) had a broken screw at the time of removal. Whether the screw was placed at the physeal scar was not significantly associated with patient decision for hardware removal (P = .80).

Conclusion

Younger and healthier patients were more likely to undergo elective removal of syndesmotic hardware. Screw distance from joint and screw placement at the physeal scar were not significantly associated with hardware removal.

Level of Evidence

Level III, retrospective cohort study.

Minifragment plating of the fibula in unstable ankle fractures

INTRODUCTION

Only 6.4-17% of the load is transmitted through the fibula when weight-bearing. Plate fixation of distal fibular fractures using minifragments (≤ 2.8 mm) could lead to similar reduction with less implant removal (IR) rates, compared to small-fragment plates (3.5 mm). We hypothesized that the use of minifragment plates is at least similar in unscheduled secondary surgery.

MATERIALS AND METHODS

In this retrospective cohort study, all patients with surgically treated distal fibular fractures between October 2015 and March 2021 were included. Patients treated with plate fixation using minifragments and patients treated with small-fragment plates were compared regarding the following outcomes: secondary dislocation, malreduction, implant malposition, nonunion, surgical site infections (SSI) and IR.

RESULTS

Sixty-five patients (54.2%) received a minifragment implant (≤ 2.8 mm) and 55 patients (45.8%) received a small-fragment implant (3.5 mm). There were no patients needing secondary surgery in the minifragment group compared to 9 patients following fixation using small-fragment implants (3 with secondary dislocation, 5 with malreduction and 1 with malposition, p = 0.001). SSI rates were 3.1% for minifragment and 9.1% for small-fragment implants (p = 0.161). Implant removal was performed significantly less often following use of minifragment implants (17.8% and 53.2%, p < 0.001).

CONCLUSIONS

In this cohort, minifragment plate fixation for distal fibular fractures is an adequate fixation method offering stable fixation with significant lower need for implant removal and comparable complications to small-fragment plates, although an adequately powered randomized controlled study is needed for implementation in a clinical setting.

LEVEL OF EVIDENCE

Therapeutic, III.

Screw-only fibular construct for Weber B ankle fractures: A retrospective clinical and cost comparison to assess feasibility for resource-limited settings

INTRODUCTION

Ankle fractures are one of the most common injuries sustained worldwide, with the majority being isolated lateral malleolus fractures. The majority of the world's population live in Low and Middle Income Countries (LMIC), where implant cost may limit surgical treatment of ankle fractures. We investigate if Weber B ankle fractures could be effectively treated with a lower-cost technique using two screws between the fibula and the tibia to neutralize an interfragmentary lag screw.

METHODS

After IRB approval, consecutive patients from January 1, 2020 to December 31, 2020 with Weber-B ankle fractures were treated using AO technique (AOT) with plate osteosynthesis neutralizing an interfragmentary screw. Syndesmotic injuries, as well as injuries to the medial malleolus or foot were treated according to the surgeon's preferences. From January 1, 2021 to December 31, 2021 these injuries were treated with a screw-only technique (SOT) with two fibula pro tibia screws to neutralize an interfragmentary screw. Patient demographics including age, sex, BMI, smoking status, associated rheumatoid arthritis, and associated diabetes mellitus were recorded. The primary outcome variable was a stable radiographic mortise at six weeks post-surgery, secondary outcome variables included clinical union, infection, hardware removal, and implant cost for lateral malleolar fixation charged to the hospital.

RESULTS

Seventeen AOT and 10 SOT constructs were included. Demographic characteristics were similar between groups. All fractures maintained a stable mortise with clinical union at 6 weeks without infection. There was a statistically significant difference in hardware removal (17.6% AOT, 50% SOT, p = 0.012). The average implant cost to the hospital of the lateral malleolar fixation was significantly less in the SOT group ($592 (SD $229)), compared to the AOT group ($1,949.97 (SD $562)), (p < 0.0001).

CONCLUSION

We introduce proof of concept of a novel lower-cost fixation strategy for Weber B ankle fractures that maintained a stable mortise with clinical union at six weeks post-surgery. However, there was a significantly higher rate of hardware removal following fixation with a screw-only construct.

Cost-effectiveness of on-demand removal of syndesmotic screwsx

Purpose

Syndesmotic screw removal following acute syndesmotic injury is a commonly performed procedure. However, recent studies suggest that the removal does not result in improved patient reported outcome, while the procedure has proved not to be without complications. The aim of this study was to present a health-economic evaluation of on-demand removal (ODR) compared to routine removal (RR) of the syndesmotic screw.

Methods

Data were collected from the RODEO trial, a randomized controlled non-inferiority trial comparing functional outcome of ODR with RR. Economic evaluation resulted in total costs, costs (in Euro) per quality adjusted life year (QALY) and costs per point improvement on the Olerud Molander Ankle Score (OMAS). This included both direct and indirect costs.

Results

Total costs for ODR were significantly lower with a mean difference of 3160 euro compared to RR (p < 0.001). The difference in QALY was not significant. The difference in OMAS at 12 months was 1.79 with an incremental cost-effectiveness ratio (ICER) of €-1763 (p = 0.512). The ICER was well below the willingness to pay. Although unit costs might vary between hospitals and countries, these results provide relevant data of cost-effectiveness.

Conclusion

The clinical effectiveness of both ODR and RR can be considered equal. The costs are lower for patients treated with ODR, which leads to the conclusion that ODR is cost-effective.

Wound infection following implant removal of foot, ankle, lower leg or patella; a protocol for a multicenter randomized controlled trial investigating the (cost-)effectiveness of 2 g of prophylactic cefazolin compared to placebo (WIFI-2 trial)

Background

Elective implant removal (IR) after fracture fixation is one of the most common procedures within (orthopedic) trauma surgery. The rate of surgical site infections (SSIs) in this procedure is quite high, especially below the level of the knee. Antibiotic prophylaxis is not routinely prescribed, even though it has proved to lower SSI rates in other (orthopedic) trauma surgical procedures. The primary objective is to study the effectiveness of a single intravenous dose of 2 g of cefazolin on SSIs after IR following fixation of foot, ankle and/or lower leg fractures.

Methods

This is a multicenter, double-blind placebo controlled trial with a superiority design, including adult patients undergoing elective implant removal after fixation of a fracture of foot, ankle, lower leg or patella. Exclusion criteria are: an active infection, current antibiotic treatment, or a medical condition contraindicating prophylaxis with cefazolin including allergy. Patients are randomized to receive a single preoperative intravenous dose of either 2 g of cefazolin or a placebo (NaCl). The primary analysis will be an intention-to-treat comparison of the proportion of patients with a SSI at 90 days after IR in both groups.

Discussion

If 2 g of prophylactic cefazolin proves to be both effective and cost-effective in preventing SSI, this would have implications for current guidelines. Combined with the high infection rate of IR which previous studies have shown, it would be sufficiently substantiated for guidelines to suggest protocolled use of prophylactic antibiotics in IR of foot, ankle, lower leg or patella.

Trial registration Nederlands Trial Register (NTR): NL8284, registered on 9th of January 2020, https://www.trialregister.nl/trial/8284