Objective To investigate the effectiveness and biomechanical analysis of 3 fixation methods of screw anterior-posterior fixation (SAPF), screw posterior-anterior fixation (SPAF), and buttress plate fixation (BPF) in treatment of posterior Pilon fractures. Methods Fifteen fresh-frozen skeleto-ligamentous lower leg specimens were harvested to establish the models of posterior Pilon fracture, and then fracture was fixed with BPF (n=5), SAPF (n=5), and SPAF (n=5). Vertical force was loaded to internal fixation failure in a speed of 1 cm/minute with servohydraulic testing machine. The instantaneous loads of 1 mm and 2 mm steps and the failure modes were recorded. Between May 2008 and December 2011, 56 patients with posterior Pilon fracture were treated with SAPF (SAPF group) in 11 cases, or SPAF (SPAF group) in 26 cases, or BPF (BPF group) in 19 cases. There was no significant difference in age, gender, injury cause, side, disease duration, and complications among groups (P gt; 0.05). Clinical and radiographic examinations were used to assess the reduction and healing of fracture; the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the visual analogue scale (VAS) were used to evaluate the functional outcomes. Results No breaking or bending was observed in all specimens, fixation failure was caused by cancellous bone compression. The instantaneous loads of 1 mm and 2 mm steps were the largest in BPF group, larger in SPAF group, and smallest in SAPF group, showing significant differences among 3 groups (P lt; 0.05). A total of 47 cases were followed up 16-54 months (9 in SAPF group, 22 in SPAF group, and 16 in BPF group), with a mean time of 35.2 months. Fixation failure was found in 2 cases of SAPF group; the other cases obtain bony union within 3 to 4 months (mean, 3.2 months) with no fixation failure. The AOFAS score was significantly lower in SAPF group than in SPAF and BPF groups (P lt; 0.05), but no significant difference was found between SPAF and BPF groups (P gt; 0.05). The VAS score was significantly higher in SAPF group than in SPAF and BPF groups (P lt; 0.05), but no significant difference was found between SPAF and BPF groups (P gt; 0.05). Conclusion SAPF could not reach enough fixation strength for the posterior Pilon fracture; both SPAF and BPF could reach rigid fixation, and have good effectiveness. And from the biomechanical points, BPF could reach better fixation strength than screw fixations.
ObjectiveTo evaluate the effectiveness of very low profile/variable angle locking plate (VLP) internal fixation for posterior Pilon fractures extending to the medial malleolus by posteromedial approach. MethodsA retrospective analysis was made on the clinical data from 13 patients with posterior Pilon fractures extending to the medial malleolus between December 2011 and August 2012. There were 4 males and 9 females with an average age of 48.9 years (range, 23-68 years). Fractures were caused by falling in 9 cases and by traffic accident in 4 cases. The locations were the left ankle in 6 cases and the right ankle in 7 cases. According to the Orthopedic Trauma Association (OTA) classification, 6 cases were rated as type 43B1, 4 cases as type 43B2, and 3 cases as type 43B3. Twelve cases had fibular fractures, including 11 cases of Denis-Weber type B, 1 case of Denis-Weber type C. The interval of injury and operation was 7-14 days (mean, 11.4 days). Open reduction was performed and VLP internal fixation was used for posterior malleolar fracture by posteromedial approach. ResultsPrimary healing of incision was obtained in all patients. Tibial nerve palsy was observed in 2 cases, and was cured after oral administration of mecobalamin. Twelve cases were followed up 12-18 months (mean, 14.5 months). According to the Burwell-Charnley's radiological evaluation system, 11 cases achieved anatomical reduction, 1 case achieved fair reduction. The fracture union time was 3-6 months (mean, 3.7 months). No loosening or breakage of internal fixation occurred during follow-up. According to the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, the results were excellent in 7 cases, good in 4, and fair in 1; the excellent and good rate was 91.7%. ConclusionVLP internal fixation for posterior Pilon fractures extending to the medial malleolus by posteromedial approach can achieve good short-term effectiveness. The high quality of reduction is acquired under direct vision with low rate of soft tissue complications.
ObjectiveTo explore the clinical outcomes of open reduction and internal fixation by posterolateral and posteromedial approaches for treating posterior Pilon fractures in elderly patients. MethodsBetween August 2009 and August 2014, 20 elderly patients with posterior Pilon fractures were treated with open reduction and internal fixation by posterolateral and posteromedial approaches. There were 14 males and 6 females, aged from 66 to 83 years (mean, 72.7 years). The causes were falling injury in 11 cases and traffic accident injury in 9 cases. All the patients had lateral malleolus and medial malleolus fractures. The time from injury to operation was 7-14 days (mean, 8.6 days). The posterolateral incision was made to expose the posterolateral bone fragments of posterior malleolus and lateral malleolus fracture, and the posteromedial incision was made to expose the posteromedial fracture fragments of posterior malleolus and medial malleolus fracture. After reduction, fracture was fixed with locking plate or cannulated screw. All the patients began to functional exercise at 1 day after operation. ResultsThe operation time was 60-110 minutes (mean, 92 minutes). The incisions healed primarily in all patients. There were no complications of incision dehiscence, infection, implant exposure, and nerve damage. No irritation sign of tendon was observed. All 20 cases were followed up for 12-18 months (mean, 13 months). The X-ray films showed that fracture healed at 3-9 months, with an average of 5.2 months. During follow-up period, no loosening or breakage of the implant was observed. The other patients could walk normally except 2 patients (over 80 years old) who could walk with crutch. According to American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the results were excellent in 12 cases, good in 4 cases, and fair in 4 cases; the excellent and good rate was 80%. ConclusionA combination of posterolateral approach and posteromedial approach for open reduction and fixation of posterior Pilon fractures can achieve satisfactory effect in elderly patients. It has the advantages of protecting ankle blood supply and avoiding the soft tissue necrosis and implants exposure.