Surgical complications of intra-articular calcaneal fracture treatment

Introduction:Introduction: The authors present complications following surgical treatment of intra-articular calcaneus fractures, in regards to the surgical technique employed, based on their own clinical material. Materials and methods: Materials and methods: The techniques analyzed included the Westhues’ technique and its modi ﬁ cation with additional bone stabilization by Kirschner wires and the percutaneous stabilization by Rapala. The research material covered the years from 1990 to 2012 and consists of 82 operated patients - 68 men (83%) and 14 women (17%). Analyzed calcaneus fractures were divided using the Essex-Lopresti classi ﬁ cation. Results:Results: The authors of the article indicate that the most frequently registered complications of surgical treatment of intra-ar-ticular calcaneus fractures in early observation were thromboembolic complications and local in ﬂ ammatory reactions of the skin at the point of incision and placing the stabilizing material. During the long-term follow-up, the post-thrombotic syndrome and algodystrophic disorders were the most common. Conclusions:Conclusions: Factors contributing to the occurrence of the complications registered were fracture morphology, ﬁ xation of bone fragments by an excessive number of stabilizing materials and prolonged immobilization of the Causes of analyzed calcaneal fractures.


INTRODUCTION
Traumatic injuries to the feet are one of the most frequently recorded in everyday clinical practice. These include fractures of the calcaneus which, according to Eastwood and Atkinas 1 and Lim and Leung 2 and others, account for 60-65% of all tarsal bone fractures, and about 2% of all traumatic damage to the locomotor system. Fractures are primarily the result of sudden axial impact of high-energy traumatic forces on the hind-foot characteristic, among others, for traffi c accidents or falls from heights. This state is recorded primarily in men between the age of 30 and 60 3,4 . The complex morphology of intra-articular calcaneal fractures results from, inter alia, placement of the foot at the moment of action of the trauma forces, the biological value of bone tissue and is dependent on a number of different kinds of systemic changes characteristic for the age of the victims, blood fl ow disorders, individual susceptibility or the use of medicine or drugs. The radiographic image of these fractures is dominated by extensive damage to the articular surface of the subtalar joint and the talocalcaneonavicular joint with changes in the value of the Böhler angle, the Gissen angle or path of the Mc Laughlin line [5][6][7][8] (Figure 1).
For the diagnosis of intra-articular fractures of the calcaneus, a number of methods are used, including, in particular, radiographs taken from the lateral and axial projection 3 , CT 9,10 or MRI 11 . In the imaging of the described fractures, the method of volumetric transformations is also frequently used 12 (Figure 2).
Treatment of calcaneus intra-articular fractures is a real challenge for many reasons, and the currently preferred surgical treatment is not always perceived as successful [13][14][15][16] .

STUDY AIM
The aim of this study was to determine the most common complications due to surgical treatment of intra-articular calcaneus fractures, including answering the following questions: 1. What are the most frequently recorded complications of intra-articular calcaneal fractures depending on their morphology and the method used for fi xation of bone fragments in the early and longterm follow-up periods? 2. Which of the intra-articular calcaneal fractures, treated surgically using the analyzed methods, are at risk of the occurrence of certain complications both in early and long-term follow-up periods? 3. What are the factors conducive to the occurrence of the analyzed complications due to surgical treatment of intra-articular calcaneal fractures? In total, falls from a height of less than 2 meters were the cause of fractures in 19 of the studied victims, which accounts for 23.1%, a fall from a height of over 2 meters in 39 of them, or 47.7%, traffi c accidents -in method of percutaneous fi xation of bone fragments with Kirschner wires using Rapala's method in 15 subjects, giving 18.3%. In women, however, in the treatment of tongue-type fractures, the Westhues method enriched with Kirschner wires was used in 3 subjects, i.e. 3.6%. In the treatment of crush fractures for 4 of the patients, or 4.8%, the Westhues method using Kirschner wires was used, and Rapala's method -in the remaining 7, thus 8.5%.

STUDY MATERIAL
All participants included in the study were operated on after 2-6 days following the fracture. The surgery was performed under spinal or epidural anesthesia. In patients who underwent fi xation of bone fragments using the Westhues method, the operated limb was immobilized in a short leg cast for a period of 6 to 8 weeks. At that time, prevention of thromboembolism using low molecular heparin and antibacterial prophylaxis in accordance with applicable principles and guidelines (Zinacef, Biodacyna, Tarcefandol) was implemented. Steinmann nails and Kirschner wires were removed from the operated calcaneal bone on the day of removing the cast. In some of the operated patients, after the removal of the cast, an empty-heel cast was put on for another 2 weeks. Physiotherapy treatment of the operated limb began 1-2 weeks after the removal of the bonding material and included a magnetic fi eld, hydro-air massage therapy, local cryotherapy as well as passive and active exercises to improve the foot joints range of motion. For this purpose, among others, the Artromot CPM device (Continuous Passive Motion method) has been used since 1998. Attempts at gradual progressive weight-bearing were taken between 10 to 12 weeks after the day of surgery.

STUDY METHODS
The research method is based on the observation of clinical registrations of complications in the perioperative period up to 3 months from the date of performing the surgery, which was adopted as the early observation pe- In the treatment of tongue-type fractures, surgical treatment based on the fi xation of the bone fragments was applied using the Westhues method or the Westhues method with additional stabilization of bone fragments with Kirschner wires. The Westhues method was applied in 19 men, accounting for 23.2%, and the Westhues method along with additional stabilization using Kirschner wires in 7 of them, namely, 8.6%. In this group, thus in men, the surgical treatment of crush-type fractures included the Westhues method with additional stabilization of the bone fragments with Kirschner wires in 27 of the subjects, that is 32.9%, and the riod and up to 6 months after treatment, which was established as the long-term follow-up period.
The obtained results were subjected to statistical analysis, which was performed using the Statistica 10 PL (StatSoft) statistical software. Data presentation includes elements of descriptive statistics (percentage distribution, mean value). The type of data distribution was assessed using the Shapiro-Wilk test. In the case of normal distribution of variables, the t-test was used to compare the groups, and in the absence of normal distribution -the U Mann-Whitney test. Similarly, to evaluate the correlation between the variables, Pearson's r correlation coeffi cient was used. The statistically signifi cant level was assumed as p<0.05.

The results obtained during the early period of observation
In men after surgical treatment of tongue-type intra-articular fractures of the calcaneus using the Westhues method of fi xation complications in the form of deep vein thrombosis (DVT), local infl ammatory reaction in the entry area of the Steinmann nails from the side of the calcaneal tuberosity and its destabilization were reported. Below knee DVT of the operated limb was diagnosed in 2 patients operated on using this method, which is 3%, local infl ammation of the skin in area of Steinmann nail entry from the side of the calcaneal tuberosity was diagnosed in 4 of them, that is 5.9%, and the destabilization of anastomosis -in 1, which gives 1.4%. In total, in men operated on using the Westhues method during the early follow-up period, complications were observed in 7 patients, i.e. in 10.3% of patients operated on this way. In the early observation period, in the men operated on the Westhues method in combination with further stabilization of bone fragments using Kirschner wires, below knee deep vein thrombosis was recorded in 3 subjects, i.e. 4.4%, and local infl ammation at the point of entry of Steinmann nails also in 3 subjects, thus 4.4%. Altogether, given this method of intra-articular calcaneal fractures treatment in males in the early follow-up period, complications were diagnosed in 6 of them, which gives 8.8%. In the same period of observation in men who were treated surgically for crush calcaneus fractures using the Westhues method with additional stabilization of bone fragments with Kierschner wires, below knee deep vein thrombosis was recorded in 2 cases, which gives 3%, and local infl ammation of the skin at the point of entry of the fi xation material occurred in 4 patients, i.e. 5.9%. Application of the Rapala method in this group of patients resulted in below knee DVA of the operated limb in 3 men, or 4.4%, and in 5 of them, or 7.3% -a local infl ammatory reaction of the skin at the point of entry of the fi xation material. In total, in the early period of observation, complications were noted in 12 cases, accounting for 20.6% in the men who underwent surgery for crush calcaneus fractures.
In total, males surgically treated using the above mentioned methods, in the early follow-up period, were diagnosed with the discussed complications in 27 cases, accounting for 39.7% of all men and 32.9% of the study group; including vein thrombosis observed in 10 patients, 14.8%, and local infl ammatory complications -16 cases, which gives 23.5% and in 1 subject, destabilization of the fi xation, which is 1.4%.
In men during the early follow-up period, below knee deep vein thrombosis of the surgically treated limb coexisted with local infl ammatory reaction of the skin in 7 patients, i.e 10.3%. In this group, 4 men with crush fractures were treated using the Westhues method in combination with further fi xation of the bone fragments using Kirschner wires, which is 5.9%, the next 2 were treated for crush fractures using the Rapala method, giving 3%, and 1 man was treated for tongue-type fractures with the Westhues method, totaling 1.4%.
In men in the early period of observation, there were no statistically signifi cant differences between the incidence of postoperative complications, depending on the type of fracture and method used for fi xation of the bone fragments (p>0.05).
In women surgically treated for tongue-type fractures using the Westhues method combined with further fi xation of bone fragments using Kirschner wires, deep vein thrombosis of the operated limb was diagnosed in 2 cases, i.e. in 14.3% of the study participants during the early follow-up period. In women treated surgically for crush fractures with the Westhues method in combination with further fi xation of bone fragments using Kirschner wires, deep vein thrombosis of the operated limb was diagnosed in 2 study participants as well, which also equals 14.3%, and in the same group (crush-type) treated using Rapala's method, 3 patients were diagnosed with DVA, which gives 21.4%, and local infl ammation of the skin in the place of fi xation material entry in 4, thus 28.6%. Below knee deep vein thrombosis of the operated limb coexisted with local infl ammatory reactions of the skin in the place of entry of Kirschner wires bundle in 6 of the operated women, which is 42.8%, including 4 patients, or 28.6% treated for crush fractures using the Westhues method along with further fi xation of the bone fragments using Kirschner wires and in 2, or in 14.3%, treated for the same reason using the Rapala method.
In the group of women in the early period of observation, there were no statistically signifi cant differences between the incidence of postoperative complications depending on the type of fracture or method of bone fragment fi xation (p>0.05).
In the early follow-up period, there were no statistically signifi cant differences between the incidence of types of postoperative complications between men and women (p>0.05).

The results obtained during the long-term follow-up period
Men operated on due to intra-articular fractures of the calcaneus in the follow-up period were diagnosed with complications in the form of post-thrombotic syndrome of shin in the operated limb, local skin necrosis at the point of fi xation material entry, which developed on the basis of earlier infl ammatory changes and Sudeck syndrome.
In men, during the long-term observation period, post-thrombotic syndrome of the operated limb was diagnosed in 3 subjects, i.e. 4.4%, in 1 subject (which gives 1.4%), co-existing local skin necrosis at the point of entry of Steinmann nails developed on the basis of pre-existing infl ammatory conditions. The patient was operated on because of a crush fracture using the Westhues method and additional stabilization of bone fragments with Kirschner wires.
Sudeck syndrome was diagnosed in 2 men in the long-term follow-up period, thus 3%, who were operated on because of the crush fractures, including 1 using the Westhues method with additional stabilization of bone fragments using Kirschner wires and in 1, surgically treated using the Rapala method.
In the long-term observation period, in 2 women (i.e. 14.3% of the analyzed cases) after surgical treatment of tongue-type fractures using the Westhues method in combination with further stabilization of bone fragments using Kirschner wires, below knee deep vein thrombosis of the operated limb was noted. In women treated surgically for crush fractures using the Westhues method in combination with additional stabilization of bone fragments using Kirschner wires, 1 case was diagnosed with below knee deep vein thrombosis of the operated limb, which gives 7.1%, whereas in subjects treated using the Rapala method in the same group of fractures (crush) 2 such cases were noted, giving 14.3%. During the long-term follow-up of the studied women, Sudeck sydrome was noted in 2 cases, i.e. 14.3% of patients treated because of tongue-type fractures using the Westhues method with further stabilization of bone fragments via Kirschner wires. Infl ammatory complications were not noted during the follow-up period in the examined group of women.

DISCUSSION
Intra-articular fractures of the calcaneus are the subject of constant interest in the environment of traumatologists, as a special group of traumatic damage to the musculoskeletal system, the treatment of which is burdened with signifi cant complication and failure rates 18,19 . This state of affairs is infl uenced by many factors perceived both in the early and longterm follow-up periods. With certainty, they include morphology of the fracture, particularly comminuted and crush fractures, sparse coverage of the lateral and medial surface of the heel by skin, which promotes the generation of necrosis and infl ammatory reactions 13 , prolonged immobilization of a limb after surgery or during non-operative treatment [20][21][22] .
The proposed methods of surgical treatment of calcaneus intra-articular fractures are associated with varying degrees of skin damage to the heel, and thus -with the possibility of creating complications in the form of necrosis or local infl ammatory reactions at the point of entry of the fi xation material to the bone or in the surgical wound. This is undoubtedly the lateral access to the calcaneus with the fi xation of the bone fragments using various types of plates 1,23 , but also minimally invasive fi xation or transdermal fi xation [24][25][26] , which include, inter alia, fi xation using the Westhues 3 and Rapala 5 methods. According to Zwippa et al. 27 , superfi cial necrosis of the surgical wound is present in 8% of patients treated surgically because of calcaneus intra-articular fractures, and surgical wound infections -in 1.2% of them. The data presented by Makki et al. 28 indicate that complications due to surgical treatment of calcaneus intra-articular fractures using lateral approach are found in 10.6% of cases. Similar data can be found in the publication by Zeman et al. 13 who reported various types of complications following surgical treatment of calcaneus intra-articular fractures during the early period of observation in 20.7% of patients, including necrosis of the surgical wound in 6.9% of them, while Zhang 29 ob-served delayed surgical wound healing because of infl ammation in 8.1% of studied patients.
These data do not substantially differ from the data noted in our own study. However, they draw attention to the occurrence of thromboembolic surgical complications in the early period of observation, which in some cases, resulted in postthrombotic syndrome during the long-term follow-up period and to the need for further vascular treatment. Longterm observation also showed bone demineralization including Sudeck syndrome, the cause of which can be seen in long-term immobilization of the operated limbs. The occurrence of cold and blue skin in these patients, accompanied by pain especially in the hindfoot, were of algodystrophic nature 30 . Apprehension towards destabilization of the fi xation especially in comminuted and crush fractures results in the conviction of the essential long-term immobilization of a limb, which not only increases the risk of bone tissue demineralization, but also leads to thromboembolic changes and impaired bone healing due to reduced blood fl ow. Based on the analysis of our own material, we are inclined to opt for the position that complications -infl ammatory, thromboembolic and necrosis of soft tissue, after surgical treatment of calcaneus intra-articular fractures -are conducive to the nature of the fi xation material, both in terms of quantity and quality. In other words -the more material is used for fracture fi xation, the greater the risk of these complications. 2. The most susceptible to the occurrence of complications due to surgical treatment of calcaneus intra-articular fractures are crushtype fractures according to the Essex-Lopresti classifi cation. 3. Factors favoring the occurrence of complications due to surgical treatment of intra-articular fractures of the calcaneus include the morphology of the fracture itself, fi xation of bone fragments with an excessive number of fi xation elements and long-term immobilization of the operated limb.