Operative Treatment of Displaced Intraarticular Calcaneal Fractures: Long-term (10-20 Years) Results in 108 Fractures Using a Prognostic CT Classification

SLR - March 2015 - Mieasha Hicks

Reference: Sanders R, Vaupel ZM, Erdogan M, Downes K. Operative Treatment of Displaced Intraarticular Calcaneal Fractures: Long-term (10-20 Years) Results in 108 Fractures Using a Prognostic CT Classification. J Orthop Trauma. 2014 Oct;28(10)551-63.

Scientific Literature Review

Reviewed By: Mieasha Hicks, DPM
Residency Program: Grant Medical Center, Columbus, Ohio

Podiatric Relevance: Understanding the long-term outcomes of intraarticular calcaneal fractures is important to help educate patients on future expectations following these significant injuries. The authors in this study evaluated the Sanders computed tomography scan classification to determine if grade of classification corresponds accurately with prognostic outcomes. They also evaluated if locking plate fixation or the addition of bone graft resulted in loss of correction or worse outcomes. Review of this information helps to confirm the validity and usefulness of the Sanders classification when evaluating intraarticular calcaneal fractures.

Methods: This is a prospective study. Data was collected from a database on all patients that were treated operatively for displaced intra-articular calcaneal fractures between January 1, 1990 and December 31, 2000. Inclusion criteria consisted of patients over the age of 18 years with a closed, isolated single-sided or bilateral displaced intra-articular calcaneal fracture.  Fractures had to be treated using lag screws and lateral non-locking plates through a lateral extensile incision. Exclusion criteria consisted of patients less than 18 years of age with open fractures, extra-articular tongue fractures, fractures treated through a medial approach, Sanders type IV fractures, dislocations of the calcaneus, fixating using other implants, an incision other than the lateral extensile approach, fractures neglected for more than 21 days after injury and additional ipsilateral trauma to the lower extremity. A total of 208 patients were eligible for the study. Preoperatively all patients had 3-view calcaneal plain films followed by a CT scan. Fractures were classified using the Essex-Lopresti on plain films and Sanders on CT scans. Surgery was performed on all patients after soft tissue swelling was minimized. A lateral extensile incision was used and the posterior facet was reduced first followed by the calcaneal body and the anterior process. A non-locking lateral calcaneal plate was then applied. Postoperatively plain films were obtained to evaluate the shape of the calcaneus, Bohler angle, the angle of Gissane, reduction of the anterior process and the calcaneal-cuboid joint surface. At final follow-up at a minimum of 10 years, plain film radiographs were repeated and a CT scan was obtained to compare the reduction of the posterior facet with the original postoperative CT scan. The CT scan was used to evaluate maintenance of reduction and any development of subtalar joint or calcaneal-cuboid joint posttraumatic arthritis. On clinical examination subtalar joint stiffness, the use of an assistive device, pain medications, shoe modifications and gait abnormalities were recorded. In addition, equinus contracture, peroneal tendon pathology, sural nerve injury and wound problems were documented. Functional outcome questionnaires were used including the Medical Outcomes Study Short Form-36, the American Orthopaedic Foot and Ankle Society ankle-hindfoot score, the Maryland Foot Score and the Ankle Osteoarthritis Score. Statistical analysis was performed by a full-time statistician.

Results: Of the 208 fractures, 108 were available for follow-up 10 years or later. The average postoperative Boheler angle was 32 degrees and the average postoperative angle of Gissane was 117 degrees.  Immediately postoperative CT scans revealed reduction of the posterior facet in 95.4% with no reduction failures. With regards to the anterior process and calcaneal cuboid joint, 25 of the 35 type 2 fractures were anatomically reduced whereas 3 of the 15 type 3 fractures could not be reduced (2.8 percent of the total 108). At final follow-up CT scan confirmed that 97 percent of fractures maintained their height. All subtalar articulations were found to have some degree of arthritis. Thirty-one of 108 fractures developed subtalar arthritis requiring an arthrodesis, this accounted for a 29 percent failure rate. Based on the classification type III fractures were 4 times as likely to need a fusion compared to type II fractures. In addition, if a C-line fracture was encountered in a type III fracture outcomes were worse. Type III fractures were also 6.5 times as likely to develop grade 4 post-traumatic arthritis compared to type II fractures.

Conclusion: This study has shown that the Sanders classification is a useful tool to help determine prognostic outcomes in patients with displaced intraarticular calcaneal fractures. Sanders type III fractures were 6.5 times as likely to develop posttraumatic arthritis and four times as likely to require subtalar joint fusion than type II fractures. This study did not include type I non-displaced fractures, which were treated non-operatively, and type IV comminuted fractures, as these fractures were primarily fused at this institution. If anatomical reduction of these displaced intraarticular calcaneal fractures is attained surgically, improved outcomes including function and gait are possible. The lateral extensile approach with non-locking lateral plate without graft filler and reduction of the posterior facet first was shown to be an appropriate fixation method. Anatomic alignment was maintained long-term using these modalities and were confirmed with CT scan at the final follow-up visit. The authors believe that if severe post-traumatic arthritis doesn’t occur within 10-20 years after the surgery, patients can expect to have minimal pain and alterations in activity. This information can help surgeons educate and counsel patients on outcomes associated with this traumatic injury.