Long-Term results of a prospective randomised study

BACKROUND

The clinical relevance and treatment of syndesmosis injury in supination-external rotation (SER) ankle fractures are controversial.

METHODS

After malleolar fixation 24 SER 4 ankle fracture patients with unstable syndesmosis in external rotation stress test were randomised to syndesmosis transfixation with a screw (13 patients) or no fixation (11 patients). Mean follow-up time was 9.7 years (range, 8.9-11.0). The primary outcome measure was the Olerud-Molander Ankle Outcome Score (OMAS). Secondary outcome measures included ankle mortise congruity and degenerative osteoarthritis, 100-mm visual analogue scale for function and pain, RAND 36-Item Health Survey, and range of motion.

RESULTS

Mean OMAS in the syndesmosis transfixation group was 87.3 (SD 15.5) and in the no-syndesmosis-fixation group 89.0 (SD 16.0) (difference between means 1.8, 95% CI -10.4-14.0, P = 0.76). There were no differences between the two groups in secondary outcome measures.

CONCLUSION

With the numbers available, SER 4 ankle fractures with unstable syndesmosis can be treated with malleolar fixation only, with good to excellent long-term functional outcome.

Radiographic parameters in gravity stress view of the ankle: Normative data

BACKGROUND

In rotational ankle injury with isolated fibular fracture, deltoid integrity is important for determining stability of ankle. Medial clear space and superior clear space in gravity stress view are parameters widely used to predict deltoid ligament tear. The purpose of this study is to report radiographic parameters in gravity stress view in normal population.

METHODS

120 persons were enrolled. Non weight-bearing ankle mortise and gravity stress view were obtained. Radiographic measurements were made by 2 investigators, including medial clear space (MCS), superior clear space (SCS), tibiofibular overlaps, tibiofibular clear space and talocrural angle. Statistical analysis included mean, mean difference, SD, 95%CI, paired T-test were calculated and subgroup analysis by foot length. Intraclass correlation coefficients were used to determine intra/interobserver reliability of measurement.

RESULTS

Mean MCS in gravity stress view was 3.19mm (95%CI 3.1-3.31). This compared to mean MCS of 3.01mm (95%CI 2.9-3.12) in mortise view which was statistically significant (P=0.02). Mean difference was 0.18mm (95%CI 0.07-0.3). SCS in gravity stress view was 3.29mm (95%CI 3.19-3.39) and when compared to MCS in gravity stress view, no statistical significance was found (P=0.158). Mean difference was 0.1mm (95%CI 0.03-0.21). In subgroup analysis by foot length, no significant difference was found in any parameters.

CONCLUSIONS

This study provides normative radiographic data for a gravity stress radiograph and supports that if measurable MCS >4mm on gravity stress view, it should be aware of an unstable ankle in supination-external rotation injury.

Transarticular external fixation versus deltoid ligament repair in treating SER IV ankle fractures: a comparative study

BACKGROUND

The topic that whether the injured deltoid ligament should be repaired when associated with ankle joint fractures is still discussed. The objective of this study was to compare the clinical effect of open reduction and internal fixation (ORIF) with deltoid ligament repair (DLR) or transarticular external fixation (TEF) in treating supination-external rotation type IV (SER IV) ankle fractures.

METHODS

Between January 2012 and December 2015, 43 patients were diagnosed as SER IV ankle fractures, 20 underwent ORIF and transarticular external fixation (TEF) without DLR (group 1), 23 were treated with ORIF and DLR (group 2). The pre- and post-operative radiographic examination were performed, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the visual analog scale (VAS), the Medical Outcomes Short Form 36-item questionnaire score (SF-36), and the ankle range of motion (ROM) were used for functional evaluation.

RESULTS

In both groups, the three scores improved significantly after surgery, but there was no significant difference between the two groups. At 6 weeks after surgery, patients in group 2 had better ankle ROM than group 1 (29.35 ± 2.033 vs. 40.35 ± 3.550, P <  0.001), but there was no difference at 12 months postoperatively. No cases of bone nonunion or post-traumatic arthritic changes were seen during the follow-up. Patients in group 1 required a shorter time to achieve fracture union than patients in group 2.

CONCLUSIONS

ORIF with TIF is an optional strategy to manage SER IV ankle fractures as it achieves comparable functional results to ORIF with DLR. It also allows patients to start relatively earlier weight-bearing and may promote fracture union.

Early and mid-term results of transarticular external fixation in the treatment of supination-external rotation type IV equivalent ankle fractures

PURPOSE

To investigate the early and mid-term results of open reduction and internal fixation (ORIF) with transarticular external fixation (TEF) but no deltoid ligament repair (DLR) in the treatment of supination-external rotation type IV equivalent (SER IV E) ankle fractures (AO/OTA classification 44-B 3.1) and provide evidence for clinical practice.

METHODS

This study cohort consisted of 22 patients with SER IV E ankle fractures that underwent ORIF with TEF but no DLR between December 2011 and December 2014. There were 13 males and 9 females, mean age 38.9 years (range, 17-73 years). Eight cases involved the left side and 14 the right side. The causes of fractures included road traffic accidents (11 cases), falling from height (6 cases) and sports injuries (5 cases). The mean period of hospitalization was 9.8 days (range, 6-14 days). For all the patients, MRI and three-dimensional CT were done before surgery and X-rays done preoperatively and during follow-ups. The external frame was kept for 8-10 weeks. The preoperative American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was 56.86 ± 4.400, the Medical Outcomes Short Form 36-item (SF-36) questionnaire score was 57.41 ± 4.102 and the visual analog score (VAS) was 5.50 ± 1.058. Patients' main complaints about inconvenience of daily life were also recorded.

RESULTS

All the 22 patients were followed up for 24-63 months (mean, 33.6 months). None of them developed nonunion during the follow-up; pin site infection was observed in one patient and posttraumatic osteoarthritis in another. At the final follow-up, the average AOFAS score, SF-36 score and VAS score were respectively 90.59 ± 5.096, 79.59 ± 5.394 and 1.82 ± 1.181, which were significantly improved compared with the preoperative data (t = 26.221, p < 0.001; t = 11.910, p < 0.001; t = 11.571, p < 0.001). The therapeutic effect was excellent in 13 cases, good in 7 cases and fair in 2 cases, with a good-excellent rate of 90.9%. Patients' main complaints were inconvenience of clothing (17 cases) and extremity cleaning (5 cases).

CONCLUSION

In the treatment of SER IV E ankle fractures, ORIF with TEF but no DLR can achieve satisfactory outcome, but long-term effect should be confirmed by large sample randomized controlled trials.

Sled fixation for horizontal medial malleolus fractures

BACKGROUND

Horizontal fractures of the medial malleolus occur through exertion of various rotational forces on the ankle, including supination--external rotation, pronation--external rotation, and pronation-abduction. Many methods of fixation are employed for these fractures, but the optimal fixation construct remains unclear.

METHODS

Horizontal medial malleolus osteotomies were performed in synthetic distal tibiae and randomized into two fixation groups: 1) two parallel unicortical cancellous screws or 2) medial malleolar sled fixation. Specimens were subjected to offset axial tension loading and tracked using high-resolution video. Clinical failure was defined as 2mm of articular displacement.

FINDINGS

There were statistically significant increases in mean stiffness (127% higher, P=0.0007) and mean force to clinical failure (52% higher, P=0.0002) with the medial malleolar sled. The mean stiffness in offset tension loading was 232 (SD 83) N/mm for medial malleolar sled and 102 (SD 20) N/mm for parallel unicortical cancellous screws. The mean force to clinical failure was 595 (SD 112) N for medial malleolar sled and 392 (SD 34) N for unicortical screws. In addition, the medial malleolar sled demonstrated elastic recoil to pre-testing alignment while the unicortical screws did not.

INTERPRETATION

Medial malleolar sled fixation was significantly stiffer and required more force to clinical failure than parallel unicortical cancellous screws. A medial malleolar sled requires more dissection to apply surgically, but provides significantly more initial fixation strength. Additionally, a medial malleolar sled acts like a tension band in its ability to capture comminuted fragments while being low profile enough to minimize soft tissue irritation.

The use and efficacy of intra-operative stress tests in supination-external rotation IV ankle fracture fixation

This study examines stress radiograph use in SER IV ankle fracture fixation; the efficacy of external rotation (ERST) and lateral hook (LHST) stress tests with incidence of subsequent fixation failure secondary to syndesmotic diastasis. 154 skeletally mature patients were admitted to our unit with ankle fractures in 12 months. 42 non-SER fractures and 32 SER fractures treated without ORIF were excluded, as were 14 which featured a syndesmotic screw in the primary ORIF. The remaining 66 SER IV fixations were included in the final sample (17 men, 49 women; median age 49 years). No stress test was performed in 51.5% of cases without a single subsequent failure in these fixations. ERST was the more commonly performed test (incidence 30.3%); negative predictive value (NPV) 0.95. Incidence of LHST was 18.2%; NPV 0.83. Both tests were performed in 6.1% of cases; NPV 0.75. The incidence of failure secondary to syndesmotic diastasis was 6.1% (4/66). Notably, there were no failures in the cases where no stress test was performed. Use of either or both external rotation and lateral hook stress tests resulted in failures to detect syndesmotic diastasis with consequent failure of fixation. This study suggests that syndesmotic injuries are not missed due to an absence of a stress test but that stress tests are not sufficiently sensitive or correctly interpreted. Clinical judgement in cases where syndesmotic injury is not present appears accurate. If syndesmotic injury is clinically suspected, apply caution and insert a syndesmotic screw rather than relying on stress test results.

The use and efficacy of intra-operative stress tests in supination-external rotation IV ankle fracture fixation

This study examines stress radiograph use in SER IV ankle fracture fixation; the efficacy of external rotation (ERST) and lateral hook (LHST) stress tests with incidence of subsequent fixation failure secondary to syndesmotic diastasis. 154 skeletally mature patients were admitted to our unit with ankle fractures in 12 months. 42 non-SER fractures and 32 SER fractures treated without ORIF were excluded, as were 14 which featured a syndesmotic screw in the primary ORIF. The remaining 66 SER IV fixations were included in the final sample (17 men, 49 women; median age 49 years). No stress test was performed in 51.5% of cases without a single subsequent failure in these fixations. ERST was the more commonly performed test (incidence 30.3%); negative predictive value (NPV) 0.95. Incidence of LHST was 18.2%; NPV 0.83. Both tests were performed in 6.1% of cases; NPV 0.75. The incidence of failure secondary to syndesmotic diastasis was 6.1% (4/66). Notably, there were no failures in the cases where no stress test was performed. Use of either or both external rotation and lateral hook stress tests resulted in failures to detect syndesmotic diastasis with consequent failure of fixation. This study suggests that syndesmotic injuries are not missed due to an absence of a stress test but that stress tests are not sufficiently sensitive or correctly interpreted. Clinical judgement in cases where syndesmotic injury is not present appears accurate. If syndesmotic injury is clinically suspected, apply caution and insert a syndesmotic screw rather than relying on stress test results.