Internal fixation of proximal humerus fractures using the T2-proximal humeral nail

Introduction

Surgical management of proximal humerus fractures remains controversial and there is an increasing interest in intramedullary nailing. Created to improve previous designs, the T2-proximal humeral nail (PHN) (Stryker^®) has been recently released, and the English literature lacks a series evaluating its results. We present a clinical prospective study evaluating this implant for proximal humeral fractures.

Method

We evaluated the functional and radiological results and possible complications. Twenty-nine patients with displaced fractures of the proximal humerus were treated with this nail. One patient was lost right after surgery and excluded from the assessment. Eighteen patients were older than 70 years.

Results

There were 21 fractures of the proximal part of the humerus and 7 fractures that also involved the shaft; 15 of the fractures were two-part fractures (surgical neck), 5 were three-part fractures, and 1 was a four-part fracture. All fractures healed in a mean period of 2.7 months. There was one delayed union that healed in 4 months. One case of avascular necrosis of the humeral head was observed (a four-part fracture), but remained asymptomatic and did not require further treatment. In one case a back-out of one proximal screw was observed. A final evaluation with a minimum 1 year follow-up was performed by an independent observer; in 18 patients, the mean Constant score was 65.7 or 76.1% with the adjustment of age and gender; in 19 patients, the mean Oxford Shoulder Score was 21.7. The results obtained with the T2-PHN nail indicate that it represents a safe and reliable method in the treatment of two- and three-part fractures of the proximal humerus. The proximal fixation mechanism diminishes the rate of back-out of the screws, a frequent complication described in the literature. Better functional results were obtained from the patients younger than 70 years, but these were not statistically significant.

     

Bone properties of the humeral head and resistance to screw cutout

Surgical treatment of fractures involving the proximal humeral head is hampered by complications. Screw cutout is the major pitfall seen in connection with rigid plating. We have exploited a bony explanation for this phenomenon.

Materials and Methods:

We examined the convex surface of the humeral head looking at the density and the topographical strength of the subchondral bone using mechanical testing of bone cylinders harvested from the humeral head. We also studied the osseous architecture of the subchondral bone and thickness of the boneplate of the humeral head using a 3-dimensional serial sectioning technique.

Results:

The bone strength and bone density correlated well and revealed large regional variations across the humeral head. Bone strength and stiffness of the trabecular bone came to a maximum in the most medial anterior and central parts of the humeral head, where strong textural anisotropy was also found. We found in particular a lower bone strength and density in the posterior and inferior regions of the humeral head. A rapid decline in bone strength within a few mm below a relatively thin subchondral plate was also reported.

Clinical Relevance:

We have in this paper explored some of the most important factors connected with screw stability at the cancellous bone level. We discovered large variations in bone density and bone strength across the joint surface rendering certain areas of the humeral head less suitable for screw placement. The use of rigid plate constructs with divergent screw directions will predictably place screws in areas of the humeral head comprising low density and low strength cancellous bone. New concepts of plates and plating techniques for the surgical treatment of complex fractures of the proximal humerus should take bone distribution, strength, and architecture into account.     

The best location for proximal locking screw for femur interlocking nailing: A biomechanical study

Background:

Proximal locking screw deformation and screw fracture is a frequently seen problem for femur interlocking nailing that affects fracture healing. We realized that there is lack of literature for the right level for the proximal locking screw. We investigated the difference of locking screw bending resistance between the application of screws on different proximal femoral levels.

Materials and Methods:

We used a total of 80 proximal locking screws for eight groups, 10 screws for each group. Three-point bending tests were performed on four types of screws in two different trochanteric levels (the lesser trochanter and 20 mm proximal). We determined the yield points at three-point bending tests that a permanent deformation started in the locking screws using an axial compression testing machine.

Results:

The mean yield point value of 5 mm threaded locking screws applied 20 mm proximal of lesser trochanter was 1022 ± 49 (range 986–1057) (mean ± standard deviation, 95% confidence interval). On the other hand, the mean yield point value of the same type of locking screws applied on the lesser trochanteric level was 2089 ± 249 (range 1911–2268). Which means 103% increase of screw resistance between two levels (P = 0.000). In all screw groups, on the lesser trochanter line we determined 98–174% higher than the yield point values of the same type of locking screws in comparison with 20 mm proximal to the lesser trochanter (P = 0.000).

Conclusion:

According to our findings, there is twice as much difference in locking screw bending resistance between these two application levels. To avoid proximal locking screw deformation, locking screws should be placed in the level of the lesser trochanter in nailing of 1/3 middle and distal femur fractures.     

Functional outcome following proximal humeral interlocking system plating for displaced proximal humeral fractures

Aim:

To assess the functional outcome following internal fixation with the PHILOS (proximal humeral interlocking system) for displaced proximal humeral fractures.

Patients and Methods:

We reviewed 30 consecutive patients treated surgically with the proximal humeral locking plate for a displaced proximal humeral fracture. Functional outcome was determined using the American Shoulder and Elbow Society (ASES) score and Constant Murley score.

Results:

Average age of the patients was 58 years (range, 19-92 years). The average overall ASES score was 66.5. The average overall Constant score was 57.5.

Conclusion:

Our results show that good fracture stability was achieved, and the functional outcome was very good in younger patients and it declined with increasing age. Early mobilization of the shoulder can be achieved without compromising fracture union.     

The treatment of established non-union of the proximal humerus using the Polarus locking intramedullary nail

Introduction:

Non-union following fracture of the proximal humerus is not uncommon, particularly in the elderly. This can be associated with significant morbidity due to pain, instability and functional impairment. The Polarus device (Acumed) is a locked, antegrade intramedullary nail designed to stabilize displaced 2-, 3- and 4-part fractures of the proximal humerus. We report our experience with the Polarus nail for the treatment of established non-union of the proximal humerus.

Materials and Methods:

A total of 7 Polarus nails were inserted for the treatment of non-union of the proximal humerus between June 2000 and July 2007. Each fracture site was opened, debrided, stabilized with a Polarus nail and then grafted with autologous cancellous iliac crest bone. The time between injury and surgery ranged from 6 to 102 months. One patient had undergone previous fixation of her fracture using Rush intramedullary rods. All patients were females, and mean age at surgery was 63.6 years (range, 49-78 years). A retrospective review of notes and radiographs was carried out. Patients were reviewed at varying intervals postoperatively (range, 13-68 months) and assessed using the Constant shoulder-scoring system.

Results:

All un-united fractures progressed to union. There were no wound complications and no postoperative nerve palsies. Functional outcome was good, even in those cases with a long interval between injury and surgery. The mean Constant score was 63 (range, 54-81). Migration of a single proximal locking screw was seen in 2 patients, and these screws required removal at 5 and 12 months, respectively, postoperatively.

Conclusion:

In our experience, a locked proximal humeral nail used in conjunction with autologous bone grafting is an excellent device for the treatment of proximal humerus non-unions.     

Radialer externer Fixateur zur geschlossenen Behandlung problematischer suprakondylärer Humerusfrakturen Typ III und IV bei Kindern und Jugendlichen

Objective

Closed, anatomical reduction and reliable fixation of type III and IV supracondylar fractures that are either difficult or impossible to treat with conventional methods.

Indications

According the Pediatric Comprehensive AO Classification for long bones this technique is preferred for type III and IV supracondylar fractures that cannot be reduced using closed standard manipulative techniques, where stable fixation using standard percutaneous wire configurations cannot be achieved, when severe swelling, open fracture, primary neurological or vascular problems (“pulseless pink hand”) or multiple injuries indicate that optimal management of the injured limb should be free from cast. In patients with comorbidities (e.g., seizures or spasticity) requiring more stable fixation.

Contraindications

In principle there are no contraindications.

Surgical technique

Prior to reduction of the fracture, fluoroscopically controlled insertion of a single Schanz screw into the lateral (radial) aspect of the distal fragment, which is defined by bulls eyeing the capitellum in the perfect lateral radiographic projection of the epiphysis, parallel to the physis. For very distal fractures this screw may be intra-epiphyseal, although usual placement is in the metaphysis just distal to the fracture line. After obtaining perfect lateral radiographic projection of the distal humeral metaphyseal–diaphyseal junction, a second Schanz screw is inserted independently into the proximal fracture fragment at the proximal end of the lateral supracondylar ridge in the sagittal plane perpendicular to the long axis of the humeral diaphysis. By bringing the screws parallel to each other in the coronal and transverse planes direct manipulations of the fragments and anatomical reduction using the so-called joystick technique is achieved. Fracture reduction can then be adjusted anatomically under fluoroscopic control and through clinical assessment. Once reduction is achieved the fragments have to be secured with a so-called “anti-rotation” K-wire. This wire significantly enhances stability and prevents pivoting of the fracture fragments around the Schanz screws in the sagittal plane and assists in prevention of medial collapse of the reduced fracture.

Postoperative management

No additional plaster cast fixation required; mobilization of the upper limb as comfort allows.

Results

The majority of children have a normal range of motion at the time of external fixator removal. At follow-up (40 months), 30 of 31 children had normal function and a normal, anatomical axis as judged against the contralateral upper limb.     

The use of locking plates in proximal humeral fractures: Comparison of outcome by patient age and fracture pattern

Purpose:

This study was undertaken to evaluate the efficacy of a proximal humeral locking plate, and to specifically study the effect of patient age and fracture type on the outcome.

Materials and Methods:

Thirty-one cases of proximal humeral fractures fixed by using the proximal humeral interlocking (PHILOS) plate were reviewed.

Results:

Average functional scores (minimum 18 months post operation) per AO / ASIF fracture type were 25.3 for type A, 21.4 for type B, and 22.7 for type C. There was no statistically significant difference between the groups. The functional scores for patients over 65 years of age were significantly inferior (P = 0.03). At a final radiological review (mean 12 months post operation), 30 (96%) of the patients demonstrated fracture union. Seven patients (22.5%) required a second surgical procedure.

Conclusion:

We obtained both good functional results and bone healing with the PHILOS plate, irrespective of fracture type; the older patients had a poorer outcome. We caution the surgeons on the high potential for reoperations with its use.     

Bone impregnated hip screw in femoral neck fracture: Clinicoradiological results

Background:

Femoral neck fractures are treated either by internal fixation or arthroplasty. Usually, cannulated cancellous screws are used for osteosynthesis of fracture neck of femur. The bone impregnated hip screw (BIHS) is an alternative implant, where osteosyntehsis is required in femoral neck fracture.

Materials and Methods:

The BIHS is a hollow screw with thread diameter 8.3 mm, shank diameter 6.5 mm and wall thickness 2.2 mm and holes in the shaft of the screw with diameter 2 mm, placed in a staggered fashion. Biomechanical and animal experimental studies were done. Clinical study was done in two phases: Phase 1 in a group of volunteers, only with BIHS was used in a pilot study and phase 2 comparative study was done in a group with AO cannulated screws and the other group treated with BIHS.

Results:

In the phase 1 study, out of 15 patients, only one patient had delayed union. In phase 2, there were 78 patients, 44 patients in BIHS showed early union, compared to the rest 34 cases of AO cannulated screws Out of 44 patients with BIHS, 41 patients had an excellent outcome, 2 had nonunions and one implant breakage was noted.

Conclusions:

Bone impregnated hip screw has shown to provide early solid union since it incorporates the biomechanical principles and also increases the osteogenic potential and hence, found superior to conventional cannulated cancellous screw.     

Lateral closed wedge osteotomy for cubitus varus deformity

Background:

Lateral closed wedge (LCW) osteotomy is a commonly accepted method for the correction of the cubitus varus deformity. The fixation of osteotomy is required to prevent loss of correction achieved. The fixation of the osteotomy by the two screw and figure of eight wire is not stable enough to maintain the correction achieved during surgery. In this prospective study we supplemented the fixation by Kirschner''s (K-) wires for stable fixation and evaluated the results.

Materials and Methods:

Twenty-one cases of the cubitus varus deformity following supracondylar fractures of the humerus were operated by LCW osteotomy during February 2001 to June 2006. The mean age of the patients at the time of corrective surgery was 8.5 years (range 6.6-14 years). The osteotomy was fixed by two screws with figure of eight tension band wire between them and the fixation was supplemented by passing two to three K-wires from the lateral condyle engaging the proximal medial cortex through the osteotomy site.

Result:

The mean follow-up period was 2.5 years (range seven months to 3.4 years). The results were assessed as per Morrey criteria. Eighteen cases showed excellent results and three cases showed good results. Two cases had superficial pin tract infection.

Conclusion:

The additional fixation by K wires controls rotational forces effectively besides angulation and translation forces and maintains the correction achieved peroperatively.     

Comparison of Kirschner wires and AO cannulated screw internal fixation for displaced lateral humeral condyle fracture in children

Purpose

This retrospective study compares Kirschner wires versus 3.5-mm diameter AO cannulated screw internal fixation in treatment for the displaced lateral humeral condyle fractures.

Methods

The study included 62 patients (42 boys, 20 girls; mean age 6.93 years; age range two to 14 years) with displaced lateral humeral condyle fractures. All patients were treated by open reduction and Kirschner wires or cannulated screw fixation. The clinical outcomes were evaluated according to the criteria of Hardacre et al. The mean follow-up period was 39.4 months (range 21–95 months).

Results

There was no statistically significant difference in clinical outcome between these two groups (P > 0.05). Five patients (16.7%) developed skin infection around K-wires, while no infection occurred in fracture with screws. An obvious lateral prominence occurred in 11 (36.7%) patients with K-wires and four (12.5%) patients with screws. Nine (30%) patients with K-wires and two (6.3%) patients with screws had a lack of 10° of extension of the elbow compared with the other side.

Conclusion

Both K-wires and cannulated screw fixation are effective in treatment for displaced lateral humeral condyle fracture. K-wires can pass through the ossific nucleus of capitulum without damaging it, but a longer period of external fixation and local skin care will be required. The screws can reduce the possibility of lateral prominence and promote the function of elbow by continuously stabilising the fracture, but a second operation is need for screw removal.     

Evaluation of surgical stabilization of metacarpal and phalangeal fractures of hand

Background:

Optimized functional results are difficult to achieve following hand injuries. This prospective study was undertaken to evaluate the functional outcome after surgical stabilization of metacarpal and phalangeal fractures.

Materials and Methods:

Forty-five fractures of digits of hand in 31 patients were managed by surgical stabilization. Five fractures were fixed with closed reduction and percutaneous Kirschner wire fixation; 10 with external fixator; 26 with open reduction and Kirschner wire fixation; and four with open reduction and plate and screw or screw fixation.

Results:

Final evaluation of the patients was done at the end of three months. It was based on total active range of motion for digital functional assessment as suggested by the American Society for surgery of hand. Overall results were excellent to good in 87%. Better total active range of motion (excellent grade) was observed in metacarpal fractures (47%) versus phalanx fractures (31%); closed fractures (57%) versus open fractures (27%); and single digit involvement (55%) versus multiple digits (29%). Excellent total active range of motion was observed with all four plate and screw/ screw fixation technique (100%) and closed reduction and percutaneous kirschner wire fixation (60%). Twenty-two complications were observed in 10 patients with finger stiffness being the most common.

Conclusion:

Surgical stabilization of metacarpal and phalangeal fractures of hand seems to give good functional outcome. Closed fractures and fractures with single digit involvement have shown a better grade of total active range of motion.     

A retrospective analysis of loss of reduction in operated supracondylar humerus fractures

Background:

Loss of reduction following closed or open reduction of displaced supracondylar fractures of the humerus in children varies widely and is considered dependent on stability of the fracture pattern, Gartland type, number and configuration of pins for fixation, technical errors, adequacy of initial reduction, and timing of the surgery. This study was aimed to evaluate the factors responsible for failure of reduction in operated pediatric supracondylar fracture humerus.

Materials and Methods:

We retrospectively assessed loss of reduction by evaluating changes in Baumann''s angle, change in lateral rotation percentage, and anterior humeral line in 77 consecutive children who were treated with multiple Kirschner wire fixation and were available for followup. The intraoperative radiographs were compared with those taken immediately after surgery and 3 weeks postoperatively. Multivariate logistic regression analysis was performed by STATA 10.

Results:

Reduction was lost in 18.2% of the patients. Technical errors were significantly higher in those who lost reduction (P = 0.001; Odds Ratio: 57.63). Lateral pins had a significantly higher risk of losing reduction than cross pins (P = 0.029; Odds Ratio: 7.73). Other factors including stability of fracture configuration were not significantly different in the two groups.

Conclusions:

The stability of fracture fixation in supracondylar fractures in children is dependent on a technically good pinning. Cross pinning provides a more stable fixation than lateral entry pins. Fracture pattern and accuracy of reduction were not important factors in determining the stability of fixation.     

Pinning technique for shoulder fractures in adolescents: computer modelling of percutaneous pinning of proximal humeral fractures

Background

In the technique of percuatenous pinning of proximal humerus fractures, the appropriate entry site and trajectory of pins is unknown, especially in the adolescent population. We sought to determine the ideal entry site and trajectory of pins.

Methods

We used magnetic resonance images of nonfractured shoulders in conjunction with radiographs of shoulder fractures that were treated with closed reduction and pinning to construct 3-dimensional computer-generated models. We used engineering software to determine the ideal location of pins. We also conducted a literature review.

Results

The nonfractured adolescent shoulder has an articular surface diameter of 41.3 mm, articular surface thickness of 17.4 mm and neck shaft angle of 36°. Although adolescents and adults have relatively similar shoulder skeletal anatomy, they suffer different types of fractures. In our study, 14 of 16 adolescents suffered Salter–Harris type II fractures. The ideal location for the lateral 2 pins in an anatomically reduced shoulder fracture is 4.4 cm and 8.0 cm from the proximal part of the humeral head directed at 21.2° in the coronal plane relative to the humeral shaft.

Conclusion

Operative management of proximal humerus fractures in adolescents requires knowledge distinct from that required for adult patients. This is the first study to examine the anatomy of the nonfractured proximal humerus in adolescents. This is also the first study to attempt to model the positioning of percutaneous proximal humerus pins.     

Transarticular screw fixation using neuronavigation: Technique

Background:

Transarticular screw placement needs highly accurate imaging. We assess the efficacy and accuracy of C1-C2 transarticular screw fixation using neuronavigation and also cast a technical note on the procedure.

Materials and Methods:

This study included a total of nine patients who underwent transarticular screw fixation using the neuronavigation system. A total of 15 screws were placed. All patients underwent postoperative CT scan with 3-Dimensional (3-D) reconstruction to check for the accuracy of implantation.

Results:

One patient had encroachment of the transverse foramen but there was no vertebral artery injury. There were no clinical complications or adverse sequelae.

Conclusion:

Neuronavigation is extremely helpful in C1-C2 transarticular screw fixation and gives excellent accuracy.     

Cadaveric study of the anatomical reference points for proximal humeral plate positioning

Background

Complications following locking plate fixation in proximal humeral fractures often related to malposition plates and inadequate screw fixation. However, literature did not define the best anatomical reference point for plate positioning. We conducted a study to assess the occurrence of subacromial impingement and screw perforation with two anatomical reference points for proximal humeral plate positioning.

Method

Sixty shoulders of 30 cadavers were dissected, and proximal humeral locking plate was placed in two different levels in the coronal plane of the upper tip of plate: (1) the proximal portion of bicipital groove group and (2) the most prominent of lesser tuberosity group. Subacromial impingement during passive forward elevation and screw perforation were assessed in relation to the plate positioning.

Results

No subacromial impingement during passive motion contacted to the plate in both groups. The calcar screw perforation rate was significantly lower in the proximal portion of the bicipital groove group (2 of 60 specimens, 3.33%) than the most prominent of lesser tuberosity group (52 of 60 specimens, 86.67%). The most proximal screws of the plate were no humeral head perforation in all specimens.

Conclusion

Our study would suggest that two anatomical reference points could be used to be the landmark to avoid the subacromial impingement and the most proximal screw perforation. However, the placement of the locking plate using the proximal portion of bicipital groove reference is better for calcar screw insertion.

     

Multifocal humeral fractures

Introduction

Multifocal humeral fractures are extremely rare. These may affect the neck and the shaft, the shaft alone, or the diaphysis and the distal humerus. There is no classification of these fractures in the literature.

Materials and methods

From 2004 to 2010, 717 patients with humeral fracture were treated surgically at our department. Thirty-five patients presented with an associated fracture of the proximal and diaphyseal humerus: synthesis was performed with plate and screws in 34 patients, and the remaining patient had an open fracture that was treated with an external fixator.

Results

Mean follow-up was 3 years and 3 months. A classification is proposed in which type A fractures are those affecting the proximal and the humeral shaft, type B the diaphysis alone, and type C the diaphysis in association with the distal humerus. Type A fractures are then divided into three subgroups: A-I, undisplaced fracture of the proximal humerus and displaced shaft fracture; A-II: displaced fracture of the proximal and humeral shaft; and A-III: multifragmentary fracture affecting the proximal humerus and extending to the diaphysis.

Discussion

Multifocal humeral fractures are very rare and little described in the literature, both for classification and treatment. The AO classification describes bifocal fracture of the humeral diaphysis, type B and C. The classification suggested in this article mainly concerns fractures involving the proximal and humeral shaft.

Conclusions

A simple classification of multifocal fractures is suggested to help the surgeon choose the most suitable type of synthesis for surgical treatment.     

Navigated pedicle screw placement using computed tomographic data in dorsolumbar fractures

Background:

Computed tomographic (CT) based navigation is a technique to improve the accuracy of pedicle screw placement. It is believed to enhance accuracy of pedicle screw placement, potentially avoiding complications arising due to pedicle wall breach. This study aims to assess the results of dorsolumbar fractures operated by this technique.

Materials and Methods:

Thirty consecutive skeletally mature patients of fractures of dorsolumbar spine (T9–L5) were subjected to an optoelectronic navigation system. All patients were thoroughly examined for neurological deficit. The criterion for instability were either a tricolumnar injury or presence of neurological deficit or both. Patients with multilevel fractures and distorted spine were excluded from study. Time taken for insertion of each pedicle screw was recorded and placement assessed with a postoperative CT scan using Laine''s grading system.

Results:

Only one screw out of a total of 118 screws was misplaced with a Laine''s Grade 5 placement, showing a misplacement rate of 0.847%. Average time for matching was 7.8 min (range 5-12 min). Average time taken for insertion of a single screw was 4.19 min (range 2-8 min) and total time for all screws after exposure was 34.23 min (range 24-45 min) for a four screw construct. No neurovascular complications were seen in any of the patients postoperatively and in subsequent followup of 1-year duration.

Conclusion:

CT-based navigation is effective in improving accuracy of pedicle screw placement in traumatic injuries of dorsolumbar spine (T9-L5), however additional cost of procuring CT scan to the patient and cost of equipment is of significant concern in developing countries. Reduced radiation exposure and lowered ergonomic constraints around the operation table are its additional benefits.     

Management of ��floating elbow�� in children

Background:

Supracondylar fractures associated with ipsilateral forearm fractures, aptly termed as “floating elbow” is a rare injury in children after a fall from height. The various authors have reported their results with conservative treatment of one or both injuries to aggressive emergency operative fixation of both components.

Materials and Methods:

During a period of three years, the author managed four cases of floating elbow in children. All cases were managed by closed reduction and pinning of both components of the injury.

Results:

All patients recovered full elbow range of motion at three months followup and were rated as excellent as per modified Flynn''s criteria. None of the patients developed cubitus varus deformity, complications related to the pins or delayed union.

Conclusions:

Early closed reduction and K wire fixation of both components of this injury gives better stability and prevents development of complications like compartment syndrome and elbow deformities.     

Intramedullary nailing of humeral diaphyseal fractures. Is distal locking really necessary?

Purpose:

Distal interlocking is regarded as an inherent part of the antegrade humeral nailing technique, but it exposes both the patient and surgeon to radiation, is time consuming, and has a potential risk of damaging neurovascular structures. We have presented our technique of diaphyseal humeral nailing without any distal interlocking in this paper.

Materials and Methods:

We have presented a series of 64 consecutive patients (33 male and 31 female, mean age: 41.5 years) with humeral shaft fractures treated with antegrade rigid intramedullary nailing without distal interlocking following a strict intra and postoperative protocol. According to the AO classification, there were 36 type A fractures, 22 type B, and 6 type C. Nails were inserted unreamed or by using limited proximal reaming and they were fitted as snuggly as possible into the medullary canal. After impaction of the nail into the fossa, we carefully tested rotational stability of fixation by checking any potential external rotation when the arm was slightly turned externally and left to the gravity forces. We were ready to add distal screws, but that was not required in these cases. Follow-up assessment included fracture union, complications and failures, and the final clinical outcome at minimum 2-year follow-up using the parameters of the constant score.

Results:

All fractures, except two, united between the 4^th and 5^th postoperative month. In one case, nail was exchanged with plate, and, in another, a larger nail was used at a second surgery. Shoulder function according to constant score, at a minimum of 2-year follow-up, was excellent or very good in 93.7% of the patients.

Conclusions:

Provided that some technical issues are followed, the method reduces intraoperative time and radiation exposure and avoids potential damage to neurovascular structures.