1. The Role of External Fixation in Treating Intra-articular Calcaneal Fractures
Jordan Ernst, MS, CPMS ’15, Tyler Harrell, CPMS ’15, and Zachary Rasor, CPMS ‘15
College of Podiatric Medicine and Surgery
Statement of Purpose
Literature Review
Discussion and Conclusion
Fractures of the calcaneus comprise approximately 2% of all fractures and 60% of tarsal fractures. These fractures can be broadly classified as intra-articular and extra-articular, with respect to involvement of the subtalar and calcaneocuboid joints. While the more commonly occurring (75%) extra-articular fractures may often be treated utilizing conservative methods, intra-articular fractures present a vastly more complex scenario [2]. The calcaneus possesses several attributes which contribute to this reality. With weight bearing, the calcaneus bears the responsibility of transmitting compressive body mass forces from the talus to the ground. Tensile forces are also applied to the calcaneus from both the Achilles tendon and the plantar aponeurosis among other static and dynamic plantar structures. In regards to the tensile forces, authors have described that within this arrangement the calcaneus functions as a lever arm or even a sesamoid bone for the Achilles-calcaneal-plantar system [3, 6]. Lastly, the calcaneus contributes to the articular surfaces of two dynamic joints in that of the Chopart’s and subtalar joints, allowing for adequate mid and hind foot motion during ambulation. With violation of an articular surface and alteration of the bony architecture, untreated calcaneal fractures can lead to substantial alterations in biomechanics as its previously listed functions become impaired. Crucially, less weight is borne on the affected foot as there is rapid unloading and shorter stance times ipsilaterally. Abnormal gait results in which the subtalar joint is no longer supple or accommodating to uneven terrain. Open Reduction Internal Fixation (ORIF) has been routinely employed to restore the biomechanics of the subtalar joint as well as the bony morphology of the calcaneus in hopes of circumventing the myriad of disabling sequelae that can afflict patients after sustainment of a calcaneal fracture. These complications include but are not limited to STJ arthritis, peroneal tendinitis, calcaneocuboid joint arthritis, heel pad damage, tarsal tunnel syndrome, a weak gastrosoleal complex, a fixed flatfoot, and residual pain [2]. While various algorithms and classification systems have been devised for the treatment and description of calcaneal fractures, no consensus has been established on the optimal treatment protocol for intra-articular calcaneal fractures. Perhaps owing to decreased familiarity and comfortability as compared with ORIF, external fixation methods for the treatment of calcaneal fractures have been reported on somewhat sporadically in the literature. While ORIF has been proven to be effective in providing ample stability for bony union, its long term complications are well documented. Most commonly these manifest as wound dehiscence and infection, with wound dehiscence being reported as high as 33% [2]. Additionally, the prolonged period of non-weight bearing required for implementation of ORIF predisposes the patient to the most troublesome possibility of post-operative heel pain from fat pad desensitization [4]. Therefore, the aim of our research was to ascertain from the literature if external fixation could produce comparable results to ORIF in treating calcaneal fractures while boasting fewer complication rates.
Recent literature regarding external fixation treatment of intra-articular calcaneal fractures has exhibited results superior to those previously published, and which now rival those produced by treatment with ORIF [3]. McGarvey et. al published the results of 18 intra-articular fractures treated with external fixation. These authors attained an average AOFAS score of 66 at an average follow up of 25 months. Scores markedly improved to an average of 77 when considering only follow up times greater than 10 months. Liccardo et. al. reported on 10 feet but with a more substantial follow up of nearly 4 years. These were intra-articular fractures of the calcaneus sustained in Iraq and Afghanistan predominately from improvised explosive devices. At last follow-up, AOFAS scores were impressive at an average of 80 with only one patient displaying signs of subtalar joint arthrosis, albeit asymptomatically. These results were similar to the scores achieved with primary arthrodesis in 6 patient’s sustaining similar injuries submitted to the same center. Utilizing a calcaneal mini-fixator, Magnan et. al treated 54 displaced calcaneal fractures, all but two involving the subtalar joint. The results produced were excellent or good in 91% of cases at an average follow-up of 49 months. In a less contemporary study, Schwartsman treated 27 Sanders type III and 17 type IV fractures with Ilizarov fixation. At an average follow up of 19 months, functional results as measured by both the Maryland and Creighton-Nebraska criteria were most impressive, with all patients attaining good or excellent results. While no studies extensively compared external fixation with ORIF, external fixation appears to bear a low complication rate. Superficial pin tract infections were found to be the most common complication with external fixation treatment and were in all instances amenable to local pin site care and oral antibiotics. These studies concluded that external fixation appears to be a reliable treatment for intra-articular calcaneal fractures and is a viable alternative to ORIF.
The classic surgical approach for the treatment of intra-articular calcaneal fractures has been ORIF in order to restore the calcaneal axis and three dimensional volume of the calcaneal anatomy. Typically, this method requires a period of NWB on the order of 8-12 weeks. With this requirement, reduced STJ ROM, STJ arthritis, and heel pain secondary to fat pad desensitization become distinct possibilities. In addition, due to the frequent traumatic nature of calcaneal fractures and the accompanying soft tissue compromise, these injuries often necessitate a waiting period of days post fracture before ORIF can be attempted. With external fixation treatment, the surgeon need not wait for restitution of the soft tissue defects and the weight bearing function of the extremity is restored expeditiously while still resting the STJ in hopes of cartilage repair. Advantageously, these attributes afford superb soft tissue stimulation and minimization of heel pad dystrophy. While this approach does not direct particular focus to restoration of the STJ articular surface as does ORIF, this may be inconsequential as attaining this objective has not been shown to correlate with clinical outcomes [1]. While some may contend that significant displacement or comminution of fracture fragments may demand ORIF, it appears that external fixation can serve as a valid substitute in most instances. This notion, along with the associated minimal complication rates, has engendered our belief that this surgical approach should be a part of any surgeon’s repertoire that treats these fractures. Regardless of the procedure chosen, calcaneal fractures are life changing injuries and comparative studies between ORIF and external fixation are warranted [5]. If these studies can be performed, more widely accepted treatment algorithms may be constructed that will guide the surgeon in treating these complex and challenging injuries.
When reconstructing the elaborate osseous framework of the calcaneus through an open technique, there are a variety of plates that can be utilized. These fixation devices can be modified and tailored based on the involved segments of bone and the degree of comminution present.
Various external fixation devices exist to reduce calcaneal fractures. Broadly, there are circular fixation devices as well as monorail constructs. The studies we present support effective results with either design. No discussion was found in the literature as to why one method would be favored over the other. While multiple fractures could demand a circular device, it would appear that in most isolated calcaneal fractures the choice is largely surgeon preference.
Intraoperative Tips and Pearls
Soft tissue compromise, such as the fracture blistering seen here, requires a “cooling down” period of several days if ORIF is to be attempted.
The patient is placed in the lateral decubitus [3, 6] or supine [1, 4] position on the operating room table. A tourniquet is applied to the thigh but not inflated [4]. The assembled fixator is attached to the tibia with transosseous wires [5]. For calcaneal wedge fractures, the two calcaneal fragments must be approximated with a Steinmann pin. A stab incision is made in the plantar skin of the heel through which the Steinmann pin is passed [1]. The pin is directed across the fracture fragments. Alignment is achieved using ligamentotaxis principles and confirmed with fluoroscopy [5]. The Steinmann pin is attached to the foot plate of the external fixator using a half-pin fixation bolt.
SURGICAL TECHNIQUE
AOFAS score
at 12 months
at about 4 years
Minimally invasive techniques
with external fixation
77 (range 62-88)
80 (range 70-92)
Primary arthrodesis of the subtalar joint
70 (range 54-84)
82 (range 78-91)
References
Schwartsman V and Schwartsman R. Reduction Techniques with the Ilizarov Frame for Calcaneal Fractures. Techniquesin Orthopaedics (2):
McGarvey WC, Burris MW, Clanton TO, and Melissinos EG. Calcaneal Fractures: Indirect Reduction and External Fixation. Foot Ankle Int : 494.
Magnan B, Bortolazzi R, Marangon A, Marino M, Dall'Oca C, Bartolozzi P. External fixation for displaced intra-articular fractures of the calcaneum. J Bone Joint Surg Br Nov;88(11):
LaBianco GJ. Percutaneous External Fixation Treatment for Calcaneal Fractures. Available at: Accessed April 18, 2014.
Liccardo M. et al. The Intra-Articular Comminuted Fractures of the Calcaneus Treatment with External Fixator. NATO OTAN STO-MP-HFM
Wound related complications, such as the one pictured here, have plagued the traditional lateral extensile approach often performed to fixate calcaneal fractures. While more minimally invasive incisions such as the sinus tarsi have reduced their occurrence, wound healing issues remain a common complication after open repair.
Results as reported by Liccardo et al on patients treated for calcaneal fractures sustained primarily in war theater