Medial Wall Fractures Research Articles

Medial Orbital Wall Fracture Caused by Forceful Nose Blowing

Medial Orbital Wall Fracture Caused by Forceful Nose Blowing

Orbital Complication of Balloon Sinuplasty

Balloon sinuplasty (BS) is a relatively new conservative approach, first licensed for the treatment of chronic rhinosinusitis in 2006. The philosophy of the technique is to improve impaired sinus drainage by enlarging stenosed or obstructed natural sinus ostiums. The recent improvements in balloon sinuplasty made virtually all paranasal sinus ostiums to be safely accessible with this technique. Compared to classical endoscopic technique, the main advantage of balloon sinuplasty is the low complication rate reported. It is very seldom to encounter major complications related to critical structures such as orbits and skull base. Since its first description, very few severe complications directly attributable to the technique have been reported in literature as of today. In this article, we report a case of medial orbital wall fracture developed due to the pressure of the inflated balloon in a balloon sinuplasty procedure.

Reconstruction of Orbital Medial Wall Fracture with Absorbable and Non-Absorbable Orbital Implant: Comparative Study

Purpose: To compare the surgical results and complications of medial wall fracture reconstruction using non-absorbable porous polyethylene implants (Medpor, Stryker Instruments, Kalamazoo, Michigan, USA) and an absorbable polymer of polyglycolic acid (PGA) and polylactic acid (PLA) (Mesh plate, Inion Ltd, Tampere, Finland). Methods: We retrospectively reviewed the data of patients who underwent reconstruction of medial wall fracture between January 2007 and June 2012 and divided them into 2 groups according to orbital implant type (Medpor, Mesh plate). Results: Among the 86 patients, 37 were treated with Medpor and 49 with Mesh plate. There was no statistically significant difference in limitation of motion or diplopia score between the 2 groups at postoperative 6 months (Fisher’s exact test, p = 0.192, p = 0.128, respectively). Mean postoperative exophthalmometry differences between the eyes were 0.49 ± 1.04 mm and 0.37 ± 0.62 mm in Medpor and Mesh plate groups, respectively, showing no statistically significant difference (independent t-test, p = 0.512). Postoperative complications such as inflammation or implant malposition were observed only in 3 patients in the Medpor group. Conclusions: No difference was observed between Medpor and Mesh plate in terms of surgical results during the postoperative 6 month period after reconstruction of orbital medial wall fracture. However, postoperative complications were observed in 3 patients in the Medpor group. J Korean Ophthalmol Soc 2014;55(5):640-645

The mechanisms of medial pedicle wall violation: insertion method is as important as correct cannulation of the pedicle.

A cadaver study aims to determine the mechanisms of medial pedicle wall violation after a correct cannulation of the pedicle. The study presents finding out the effect of insertion angle and insertion force on medial wall violation. We used 100 lumbar pedicles of cadavers. Special wooden blocks were produced to simulate a fixed angle fault after a correct pedicle cannulation. Pedicles were divided into 4 groups: 10-degree free drive (group 10), 15-degree free drive (group 15), 10-degree push drive (group 10P), and 15-degree push drive (group 15P). After insertion of pedicle screws, laminectomies were done and the pedicles were evaluated from the inside. Pedicle complications were more in group 10P than group 10 (P = 0.009). Medial wall fracture (P = 0.002) and canal penetration were more in group 15P than group 15 (P = 0.001). Groups 10P and 15P were similar regarding medial wall fractures but canal penetration was significantly higher in group 15P (P = 0.001). Medial wall breaches can happen after correct cannulation of pedicles. Change in insertion angle is one factor but the most important factor is the use of a pushing force while inserting a screw. The pedicle seems to be extremely tolerant to insertion angulation mistakes up to 10 degrees and tends to lead the screw into the correct path spontaneously.

Management of Extensive Blowout Fracture of Combined Orbital Floor and Medial Wall: A Challenge in Reconstruction

ABSTRACTOrbital blowout fractures are common sequelae of blunt trauma to periocular region. Combined orbital floor and medial wall fractures are more complicated than either alone, because there may not be adequate peripheral bony support for standard implants. The transition zone between orbital floor and medial wall is difficult to visualize intraoperatively and makes even more difficult to visualize in dissection further posteriorly. In our case, patient sustained orbital blowout fracture with herniation of periorbital tissue in maxillary sinus as well as ethmoidal sinus. After undergoing successful orbital reconstruction surgery, eyeball was repositioned to its original position. There was no enophthalmos and patient had no restriction in eye movement and perception to light was similar in both the eyes. Pupillary reflex to light was brisk and similar in both the eyes.How to cite this articleShah PD, Mukherjee S. Management of Extensive Blowout Fracture of Combined Orbital Floor and Medial Wall: A Challenge in Reconstruction. Int J Otorhinolaryngol Clin 2014;6(3):123126.

Reconstruction of severe medial orbital wall fractures using titanium mesh plates by the pericaruncular approach

Medial orbital wall fractures can cause severe aesthetic and functional complications, if not treated properly. The aim of this study was to prospectively evaluate the use of titanium mesh plates inserted through the pericaruncular approach for the treatment of medial orbital wall fractures. Between 1 July 2010 and 1 January 2013, a total of 17 patients with large medial orbital wall defects were treated. All of the large bony defects were treated using titanium mesh plates inserted through the pericaruncular approach. All patients had anatomically correct orbital wall reconstruction as accessed by immediate postoperative computed tomography scan. One patient with large bony defects presented with diplopia after the primary procedure. Re-operation was needed for correction. After surgery, the diplopia was corrected. In all patients, postoperative morbidity was minimal and cosmetic results were excellent. Titanium mesh may be a valuable material for the reconstruction of severe medial orbital wall defects. Its advantages include excellent structural support, shorter operative time, and ease of being moulded into the desired shape. The pericaruncular approach may allow for or give direct access to the medial orbital wall and orbital apex without any cutaneous incision or disruption of the medial canthal ligament, and insertion of titanium mesh plates is possible under direct vision. It is proposed that this technique could be advantageous in the reconstruction of severe medial orbital wall fractures.

Two-Year Follow-up on the Use of Absorbable Mesh Plates in the Treatment of Medial Orbital Wall Fractures

BackgroundAbsorbable materials offer many advantages in the reconstruction of orbital walls; however, the possibility of postoperative enophthalmos after complete absorption cannot be excluded. We evaluated the postoperative results of absorbable mesh plates used as onlay implanting on the medial orbital wall to determine whether they are suitable for medial orbital wall reconstruction.MethodsThe study included 20 patients with medial orbital wall fractures who were followed up for more than 2 years postoperatively. We used absorbable mesh plates in all of the patients. We measured the following: the changes in the expanded orbital volume by comparing the preoperative and postoperative computed tomography (CT) scans and the degree of clinical enophthalmos.ResultsThere were no major complications associated with the use of absorbable materials such as infection, migration, or extrusion of mesh plates during the long-term follow-up. The orbital volumetric changes between the preoperative and postoperative CT scans were not statistically significant. However, the expanded orbital volume was not related to the degree of clinical enophthalmos.ConclusionsThe reconstructed orbital wall may provide supportive scar tissue to the orbital contents even after the absorbable materials have dissolved completely. Absorbable mesh plates could be another option for the reconstruction of the medial orbital wall.

Horner Syndrome Due to Vertebral Artery Stenosis

The author reports a rare case of Horner syndrome in a patient who resulted from stenosis of the vertebral artery after blunt trauma. A 31-year-old man was transferred to our department for evaluation of left medial orbital wall and nasal bone fractures. Five days ago, he was hospitalized due to multiple second to fourth rib fractures of the right chest following blunt trauma of the face, neck, and chest. Surgery was performed. Ten days later, he complained of drooping of the right eyelid. Physical examination revealed a discrete miosis and ptosis with normal levator function in the right eye. A workup for Horner syndrome was performed. Magnetic resonance angiography of the head and neck revealed a stenosis of the distal part of the right vertebral artery without the abnormality of carotid artery. He wore a cervical collar and underwent anticoagulation. However, Horner syndrome was not resolved over the next 12 months. Acute traumatic Horner syndrome may be associated with vertebral artery dissection in which the possibility of life-threatening injury can be masked.

Management of Pure Medial Orbital Wall Fracture With Autogenous Bone Graft

The orbit is an irregular conical cavity formed from 7 bones including the frontal, sphenoid, zygomatic, maxillary, ethmoid, lacrimal, and palatine bones. Fractures of the internal orbit can cause a number of problems, including diplopia, ocular muscle entrapment, and enophthalmos. Although muscle entrapment is relatively rare, diplopia and enophthalmos are relatively common sequelae of internal orbital fractures. Medial orbital wall fracture is relatively uncommon and represents a challenge for its anatomical reconstruction. In this context, autogenous bone graft has been the criterion standard to provide framework for facial skeleton and orbital walls. Therefore, it is possible to harvest grafts of varying size and contour, and the operation is performed through the bicoronal incision, which is the usual approach to major orbital reconstruction. Thus, this article aimed to describe a patient with a pure medial orbital wall fracture, and it was causing diplopia and enophthalmos. The orbital fracture was treated using autogenous bone graft from calvarial bone. The authors show a follow-up of 12 months, with facial symmetry and without diplopia and enophthalmos. In addition, a computed tomography scan shows excellent bone healing at the anterior and posterior parts of the medial orbital wall reconstruction.

Combined Orbital Floor and Medial Wall Fractures Involving the Inferomedial Strut: Repair Technique and Case Series Using Preshaped Porous Polyethylene/Titanium Implants

Background Combined orbital floor and medial wall fractures can be technically challenging to repair, particularly when the inferomedial strut is involved. A surgical repair technique is described utilizing a single preshaped porous polyethylene/titanium implant to span both defects. Methods Retrospective interventional case series. Results Fracture repair was performed on 17 orbits (16 patients) between October 2009 and February 2012. Subsequent surgical revision was required in three cases (18%). Visual acuity was stable or improved in all cases. Of 7 patients with preoperative diplopia, 5 improved and 2 remained stable postoperatively, and there were no cases of new or worsened diplopia following surgery. Postoperative asymmetry in Hertel exophthalmometry averaged 1.0 mm (range 0 to 2 mm). Preoperatively, average orbital volume was 122.7% compared with control (range 109 to 147%, standard deviation [SD] 9.6), which improved to 100.3% postoperatively (range 92 to 110%, SD 5.7). The average decrease in orbital volume was 22.5% (range 10 to 54%, SD 11.4, p < 0.001). Conclusions With careful preoperative planning and meticulous surgical technique, combined orbital floor and medial wall fractures involving the inferomedial strut can be successfully repaired with a preshaped porous polyethylene/titanium implant through a transconjunctival/transcaruncular approach with inferior oblique disinsertion.

The Correlation between the Degree of Enophthalmos and the Extent of Fracture in Medial Orbital Wall Fracture Left Untreated for Over Six Months: A Retrospective Analysis of 81 Cases at a Single Institution

BackgroundIn patients with medial orbital wall fracture, predicting the correlation between the degree of enophthalmos and the extent of fracture is essential for deciding on surgical treatment. We conducted this retrospective study to identify the correlation between the two parameters.MethodsWe quantitatively analyzed the correlation between the area of the bone defect and the degree of enophthalmos on computed tomography scans in 81 patients with medial orbital wall fracture who had been left untreated for more than six months.ResultsThere was a significant linear positive correlation between the area of the medial orbital wall fracture and the degree of enophthalmos with a formula of E=0.705A+0.061 (E, the degree of enophthalmos; A, the area of bone defect) (Pearson's correlation coefficient, 0.812) (P<0.05). In addition, that there were no cases in which the degree of enophthalmos was greater than 2 mm when the area of the medial orbital wall fracture was smaller than 1.90 cm2.ConclusionsOur results indicate not only that 2 mm of enophthalmos corresponds to a bone defect area of approximately 2.75 cm2 in patients with medial orbital wall fracture but also that the degree of enophthalmos could be quantitatively predicted based on the area of the bone defect even more than six months after trauma.

Change of the Orbital Volume Ratio in Pure Blow-out Fractures Depending on Fracture Location

The purposes of this study were to observe bony orbital volume (OV) changes in pure blow-out fractures according to fracture location using a facial computed tomographic scan and to investigate whether the OV measurements can be used as a quantitative value for the evaluation of the surgical results of the acute blow-out fracture.Forty-five patients with unilateral pure blow-out fracture were divided into 3 groups: inferior (group I), inferior medial (group IM), and medial (group M) orbital wall fracture. The OV and the orbital volume ratio (OVR) were prospectively measured before and 6 months after surgery with the use of 3-dimensional computed tomographic scans, and the Hertel scale was measured with a Hertel exothalmometer.The preoperative OVR increased to the greatest extent in group IM, and the mean preoperative OVR was 121.46. The mean preoperative OVR in group I was significantly higher than that of group M (P = 0.005). The OV and OVR revealed a statistically significant decrease after the surgery (P = 0.000). The Hertel scale improved from -1.04 mm before the surgery to -0.78 mm after the surgery, but no significant difference was observed (P = 0.051).The OVR was useful as a quantitative value to evaluate pure blow-out fractures, compared with that of the Hertel scale. Fracture location-associated OVR studies are needed to make volume guidelines of blow-out fracture surgery.

Reply

Sir: We thank Dr. Shinder for his thoughtful letter regarding our article.1 We agree with the assessment that there is a scarcity of literature describing strict indications for repair of medial wall fractures. In our institution, we use the following criteria for surgical repair: a defect size larger than 2cm2 along the medial wall with evidence of soft-tissue herniation into the defect, medial rectus entrapment with associated diplopia, or enophthalmos greater than 2mm. In addition, in subjects with medial wall fractures and concomitant large orbital floor defects, wherein the medial aspect of the floor was compromised, the medial wall repair was undertaken to reconstitute the inferomedial aspect of the orbital anatomy. In contrast, nonoperative management was used in cases where the defects were small (<2cm2), those without associated soft-tissue entrapment, those that demonstrated no significant enophthalmos, and those in which ipsilateral orbital floor or midfacial fractures did not meet criteria for surgical repair. DISCLOSURE The authors have no financial interest to declare in relation to the content of this communication. Chad R. Gordon, D.O. The Johns Hopkins University School of Medicine Baltimore, Md. Srinivas M. Susarla, D.M.D., M.D., M.P.H. Michael J. Yaremchuk, M.D. Department of Surgery Division of Plastic and Reconstructive Surgery Massachusetts General Hospital Boston, Mass.

Supporting Implant Technique for Repairing Large Medial Orbital Wall Fractures

To introduce a new surgical technique for repairing large medial wall fractures stably with insufficient bony structures. This is a case series of 29 patients who underwent surgery for repairing large medial wall fractures using the new supporting implant technique in Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. Medical records and radiologic images of the patients were reviewed retrospectively. The outcomes evaluated were the incidence and the degree of diplopia and enophthalmos, and orbital volume restoration after surgery. The institutional review board approved this study, and the study adhered to the tenets of the Declaration of Helsinki. Orbital reconstruction using the supporting implant technique was performed without any complications. The incidence of diplopia was 51.7% including 6.9% of significant diplopia before and 27.6% with no significant diplopia 3 months after surgery (p = 0.022). The average enophthalmos was successfully corrected from 0.93 mm preoperatively to 0.36 mm at 3 months postoperatively (p = 0.001). Orbital volume was corrected from 25.71 to 23.59 cm2 after surgery, which was not significantly different from the contralateral unaffected orbit (p = 0.157). The supporting implant technique is a simple and effective surgical method that provides sufficient support and prevents implant migration in large medial orbital wall fractures.

Posttraumatic orbital emphysema: incidence, topographic classification and possible pathophysiologic mechanisms. A retrospective study of 137 patients

The aim of this study was to retrospectively evaluate the incidence of posttraumatic orbital emphysema (OE) and to propose a radiologic topographic classification as well as a possible pathophysiologic model. Orbital fine-cut (1 mm) computerized tomographic scan slices from 137 patients were used to assess the fracture's type, the presence and position of OE, and periorbital tissue herniation. The OE was categorized into the following 5 compartments: subcutaneous periorbital, peribulbar, retrobulbar extra- and intraconal, and pterygopalatine fossa. The incidence of OE was 61%. OE was more frequently associated with isolated medial wall (78%; P < .001) and combined medial wall/orbital floor (82%; P < .01) fractures. Palpable isolated subcutaneous eyelid emphysema was not related to fracture's type (P = .85). OE suggested medial wall fractures alone or combined with orbital floor fractures. Pathophysiologically, according to the Poiseuille law, the difference in length between the ethmoid and sinusal infundibulii could explain the increased incidence of OE when the medial wall is involved.

Oculocardiac reflex in a medial orbital wall fracture without clinically evident entrapment

In this report, we describe a patient with a medial wall orbital fracture, who presented with vasovagal-like symptoms secondary to an oculocardiac reflex. This case is unusual because the patient had no other clinical evidence of muscle entrapment. A 15-year-old male presented with daily 5-10 min episodes of dizziness, light headedness, and nausea consistent with a vasovagal reaction. On examination, the patient had full extra ocular motility and was orthotropic in all fields of gaze. On computed tomography a comminuted medial orbital wall fracture was identified. The adjacent medial rectus muscle was in normal position, but was “rounded” relative to the contralateral side. The patient underwent fracture repair with immediate resolution of all symptoms. Symptoms related to a vasovagal response may occur with orbital fractures despite normal extra ocular motility. Presumably this relates to tension or pulling on an extra ocular muscle, which is not to a degree that alteration in function is appreciable clinically.

Quantitative Assessment of Medial Orbit Fracture Repair Using Computer-Designed Anatomical Plates

The purpose of this study was to objectively assess the accuracy of orbital reconstruction in patients with medial wall fractures following placement of computer-designed, prebent anatomical mesh plates by means of a transconjunctival-retrocaruncular approach. This was a retrospective, cohort study of consecutive subjects with facial trauma who underwent reconstruction of medial wall/orbital floor defects over a 12-month period at a level I trauma center. All subjects had preoperative and postoperative computed tomographic scans with 1.25-mm slices formatted in the axial, coronal, and sagittal planes with a minimum of 3 months' follow-up. Preoperative and postoperative orbital volumes were computed using integrated analysis over the orbital slices. The volumes were compared using nonparametric paired samples comparisons (Wilcoxon signed ranks test). For all analyses, p ≤ 0.05 was considered significant. Fifteen subjects underwent repair of 17 medial wall fractures. The mean patient age was 37 ± 16 years (range, 18 to 59 years); one subject was female. Motor vehicle-related incidents and assaults were the most common mechanisms of injury. The average postoperative volume for the fractured sides was 22. 2 ± 2.1 cm3 (range, 19.9 to 26.9 cm3) and was statistically significantly lower than the preoperative volume on the fractured side (24.18 ± 2.57 cm3; p < 0.001). One patient (6.7 percent) experienced a postoperative complication requiring reoperation. Computer-designed, prebent anatomical mesh plates placed using a transconjunctival-retrocaruncular approach for reconstruction of medial wall fractures with orbital floor components reliably results in restoration of contour and volume, with a low complication rate. Therapeutic, IV.

Endoscopic Transcaruncular Repair of Large Medial Orbital Wall Fractures Near the Orbital Apex

To study the suitability of an endoscopic transcaruncular approach (ETA) for repair of large medial orbital wall fractures (MOWFs) near the orbital apex. A retrospective, noncomparative case series with description of the surgical technique. Ninety-three consecutive patients (93 orbits) with large isolated MOWFs near the orbital apex. The isolated MOWFs were determined by computed tomography (CT) scans of the orbit in all patients. All patients underwent fracture repair by an ETA, and the vertical and horizontal dimensions of the defects were measured during surgery. Porous polyethylene sheets (1.0 mm thick) were used to repair the bony defects. Patients were followed for 6 to 15 months. Size of vertical and horizontal fracture defects, rate of complete repair of the fracture defects, correction of enophthalmos, resolution of diplopia, and complications 6 months after surgery. All surgeries were completed uneventfully. The mean postoperative follow-up time was 9.7 ± 3.0 months. Under direct endoscopic visualization, all entrapped and herniated orbital contents were released and reposited, the entire boundary of the fractures were exposed adequately, and the implants were placed to overlie all edges of the fracture stably in all cases. The vertical and horizontal fracture defects measured during surgeries ranged from 16 to 30 mm and from 25 to 34 mm, respectively. Six months after surgery, complete reconstruction of the bony defects was demonstrated by orbital CT scans, and symmetry of the both eyes was acquired in 92 of 93 patients (98.9%). Of 30 patients with significant preoperative enophthalmos of more than 2 mm, 29 (96.7%) were corrected, with a mean improvement of 3.37 ± 0.77 mm. Diplopia within the 30° visual field of the gaze was resolved in 40 of 43 patients (93.0%). Three patients (7.0%) had residual diplopia on medial gaze because of presumed paralysis of the medial rectus muscle. Intraorbital hemorrhage occurred in 1 patient the day after surgery and resolved with conservative treatment. The ETA seems to be a useful method for recovery of the normal anatomic features of the orbits for patients with large MOWFs near the orbital apex.

The Usability of the Upper Eyelid Crease Approach for Correction of Medial Orbital Wall Blowout Fracture

There are many approaches to the medial orbital wall. However, most of them have problems with limitation of exposure, scarring, and postoperative inflammatory symptoms related to the eye. The authors used an upper eyelid crease approach to overcome these problems and investigate the usefulness of this approach. Between 2009 and 2011, the authors used this approach in 22 patients with medial orbital wall fractures. Incisions were performed on the medial one-third of the crease and a 2- to 3-mm superomedial extension along a relaxed skin tension line. Postoperative computed tomographic scans demonstrated complete reduction and accurate reconstitution of the bony defect in all cases. The initial two cases had revision to correct the implant position. Follow-up ranged from 8 to 28 months, with an average of 12 months. Complications related to the operation were not observed. Diplopia and limitation of eye movement resolved in most cases. Two patients had persistent diplopia for more than 6 months that decreased with time. Enophthalmos of more than 2 mm was not observed in any orbit. The operative scar was inconspicuous. This approach provides several advantages, including ease of exposure, and is more familiar to the plastic surgeon than the transconjunctival approach. There is little need to retract the globe laterally, thus minimizing postoperative inflammatory symptoms related to the eye. Therefore, the authors suggest that this method should be considered as a natural and useful surgical approach to medial orbital blowout fractures.

Clinical Characteristics and Treatment of Blow-out Fracture Accompanied by Canalicular Laceration

Blow-out fracture and canalicular laceration can occur simultaneously as a result of the same trauma. Despite its importance, little research has been conducted to identify clinical characteristics or surgical techniques for repair of a blow-out fracture accompanied by canalicular laceration. The aim of this study was to evaluate the clinical characteristics, the surgical approach, and the outcomes. Thirty-four eyes of 34 patients who underwent simultaneous repair of canalicular laceration using silicone tube intubation and reconstruction of blow-out fracture were included. Medical records were retrospectively reviewed for patient demographics, nature of injury, affected canaliculus, location, and severity of blow-out fracture, associated facial bone fracture, ophthalmic diagnosis, length of follow-up period, and surgical outcome. Mean patient age was 40.0 years (range, 17-71 y). The mean follow-up was 7.3 months. Fist to the orbital area (10 patients, 29.4%) was the most common cause. There were 24 lower canalicular lacerations (70.6%), 6 upper canalicular lacerations (17.6%), and 4 upper and lower canalicular lacerations (11.8%). Isolated medial wall fractures were most common (area A4: 20/34, 58.8%). Fractures involving both the floor and medial wall and maxillo-ethmoidal strut (areas A1, A2, A3, and A4) were the second most common (6/34, 17.6%), and floor and medial wall with intact strut (areas A1, A2, and A4) were injured in 6 patients (17.6%). Pure inferior wall fractures were least frequent (areas A1 and A2: 2/34, 5.9%). The severity of the fracture was severe in most patients except for 1 linear fracture with tissue entrapment and 1 moderate medial wall fracture (32/34, 94.1%). There was lid laceration in 20 patients (58.8%). Nasal bone fracture (5/34, 14.7%) was the most common facial bone fracture. Tubes were removed at a mean of 3.3 months (range, 3-4 mo). In total, 31 patients (91.2%) achieved complete success in canalicular laceration and blow-out fracture repair. No significant complications were encountered. Fractures involving the medial wall with a lower canalicular laceration were the most common among concomitant blow-out fractures and canalicular lacerations. The severity of the fracture was most often classified as severe. Computed tomographic scan of the orbit and facial bones for identification of any additional injuries such as orbital wall and facial bone fractures should be performed in patients with canalicular laceration. To avoid disruption of the medial canthal area, repair of the canalicular laceration with silicone tube intubation was performed before reconstruction of the blow-out fracture through transconjunctival and transcaruncular approaches. Finally, the tube was fixed after blow-out fracture surgery, and these surgical orders yielded good surgical outcomes without complications.