Accuracy of an image-free handheld hip navigation device for total hip arthroplasty in a lateral decubitus position

doi:10.21203/rs.3.rs-1757418/v1

Download PDF

Research Article

Accuracy of an image-free handheld hip navigation device for total hip arthroplasty in a lateral decubitus position

https://doi.org/10.21203/rs.3.rs-1757418/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted

You are reading this latest preprint version

Background: Portable navigation systems have been developed for use in total hip arthroplasty (THA) in recent years. The purpose of this study was to investigate the accuracy of cup insertion in primary THA using an image-free handheld navigation device in the lateral decubitus position.

Methods: This retrospective study included 68 consecutive cementless THAs performed using an image-free handheld navigation device and 68 consecutive THAs performed without a navigation system as historical controls. All cases underwent THAs in a lateral decubitus position. Postoperative cup radiographic inclination and radiographic anteversion were assessed, and the accuracy of cup insertion was compared between the two groups. Navigation error was also assessed.

Results: The mean absolute errors of the postoperative measured inclination from the target inclination were 3.9° ± 2.2° in the navigation group and 8.5° ± 6.9° in the control group (p<0.001). The mean absolute errors of anteversion were 4.8° ± 3.5° in the navigation group and 11.4° ± 6.6° in the control group (p<0.001). The percentage of cups inside Lewinnek’s safe zone was 94% in the navigation group and 37% in the control group (p<0.001). The mean absolute values of navigation error were 3.1° ± 2.1° in inclination and 4.2° ± 2.8° in anteversion. No factors affected the navigation errors.

Conclusions: Use of an image-free handheld navigation device can improve the accuracy of cup insertion compared with conventional manual technique in THA in the lateral decubitus position.

Image-free handheld navigation

Total hip arthroplasty

Acetabular cup

Malposition of the acetabular component in total hip arthroplasty (THA) may increase the risk for postoperative complications such as prosthetic impingement [1], dislocation [2], and accelerated polyethylene wear [3]. The conventional technique using the free-hand technique or a mechanically guided technique to determine intraoperative acetabular component position has resulted in inaccurate cup alignment [4]. Among the measures to improve surgical accuracy, use of computer-assisted navigation systems such as a computed tomography (CT)-based navigation system and an image-free navigation system has been shown to help achieve optimal cup alignment [5]. However, these large-console navigation systems have the disadvantage of high cost. Furthermore, CT-based navigation systems require radiation exposure, because multidirectional fluoroscopic images must be matched with 3-dimensional (3-D) pelvic images reconstructed from preoperative CT data.

The Naviswiss (Naviswiss AG, Brugg, Switzerland) is a newly introduced, image-free, handheld navigation device. The navigation unit includes an infrared stereo camera that measures the position and orientation of small tags mounted to the pelvis. The tags are mounted with bone pins to provide pelvic orientation data to the camera unit. Although this device costs much less than the conventional large-console navigation systems, the accuracy of acetabular cup insertion is not clear.

The purpose of this study was to assess the accuracy of acetabular cup placement in primary THA using the Naviswiss in the lateral decubitus position.

From April 2020 to July 2021, 68 consecutive hips in 66 patients underwent primary cementless THA using the Naviswiss in the lateral decubitus position (the navigation group). There were 55 women and 11 men, with a mean age of 72 years (range, 61–91 years) and a mean body mass index (BMI) of 25 kg/m² (range, 18–33 kg/m²). The preoperative diagnoses were osteoarthritis (OA) in 61 hips (Crowe group 1, 55 hips; group 2, 1 hip; group 3, 2 hips; group 4; 3 hips), osteonecrosis of the femoral head (ONFH) in 4 hips, rapidly destructive coxarthrosis (RDC) in 2 hips, and rheumatoid arthritis (RA) in 1 hip. The surgical approaches were the posterior approach in 23 hips and the superior approach in 45 hips. The criterion for the superior approach was slight to moderate deformity of the acetabulum or femoral head because this approach was more minimally invasive than the posterior approach. We referred to the report in which Murphy described the surgical technique of the superior approach [6]. In this study, an 8- to 10-cm incision was made starting at the tip of the greater trochanter and extending proximally, in line with the femoral shaft axis. The gluteus maximus fibers were spread, and the gluteus medius was mobilized anteriorly. The piriformis tendon was mobilized posteriorly, the gluteus minimus muscle was mobilized anteriorly, and the superior capsule was exposed. A vertical capsulotomy was performed from the trochanteric fossa to the acetabular rim. The anterior capsule and the posterior capsule were retracted, and the entire acetabulum was exposed. The subsequent procedures for excision of the labrum, reaming of the acetabulum, insertion of the cup, and repair of the capsule were similar to the posterior approach. All patients in the navigation group had a SQRUM TT SHELL (Kyocera, Osaka, Japan). As a control group, 68 retrospective consecutive hips in 56 patients who underwent THAs with manual implant techniques in the lateral decubitus position between February 2012 and April 2017 were included. There were 51 women and 5 men with a mean age of 62 years (range, 34–86 years) and a mean BMI of 24 kg/m² (range, 15–37 kg/m²). The preoperative diagnoses were OA in 63 hips (Crowe group 1, 51 hips; group 2, 8 hips; group 3, 3 hips; group 4; 1 hip) and ONFH in 5 hips. The surgical approach was the posterior approach in all cases. A Regenerex Ringloc Acetabular Component was used in 37 hips, a Continuum Acetabular Shell was used in 22 hips, a G7 PPS Finned BoneMaster Acetabular Shell was used in 8 hips, and Trilogy Acetabular Shell was used in 1 hip (all components from Zimmer Inc, Warsaw, IN). This cohort was a part of the control group of our previous report [7]. The patients’ demographic characteristics are shown in Table 1.

Table 1

Patients’ demographic characteristics
	Navigation group	Control group	p-value
Gender (Women/Men)	55/11	51/5	ns
Age (years)	72 (61–91)	62 (34–86)	< 0.001
Body mass index (kg/m²)	25 (18–33)	24 (15–37)	ns
Diagnosis
Osteoarthritis	61	63	ns
Crowe group 1	55	51
Crowe group 2	1	8
Crowe group 3	2	3
Crowe group 4	3	1
Osteonecrosis of the femoral head	4	5
Rapidly destructive coxarthrosis	2	0
Rheumatoid arthritis	1	0
Surgical approach
Posterior approach	23	68	< 0.001
Superior approach	45	0	< 0.001

The Naviswiss consists of a handheld navigation device and miniature precision tracking tags. Intraoperatively, all patients were placed in the lateral decubitus position and fixed with the conventional lateral fixation device, and two fixation pins, 3.0 mm in diameter, were placed on the iliac crest to fix the tag. The other tag was attached to the pelvic caliper. A point on the chest that lies on the patient’s mid chest axis, and the greater trochanter were identified. Both points were palpated with the pelvic caliper and the body axis was registered (Fig. 1a). During cup impaction, this tag was attached to the cup impactor, and cup inclination and anteversion were measured (Fig. 1b). Angles displayed on the screen were the radiographically defined angles (Fig. 1c). The cup orientation was planned to be 40° in radiographic inclination and 15° in radiographic anteversion relative to the functional pelvic plane (FPP) based on the definitions of Murray [8]. In the control group, because cup placement was performed using a mechanical alignment guide, the target angle of cup operative inclination was 40° and of anteversion was 20° (radiographic inclination of 42° and radiographic anteversion of 15°).

Postoperative cup position was assessed using a 3D-Template system after CT examination (ZedHip, Lexi, Tokyo, Japan). Cup radiographic inclination and anteversion were evaluated relative to the FPP. The absolute values of errors of radiographic inclination and anteversion were calculated by subtracting postoperative angles from the target angles. The proportions of hips within Lewinnek’s safe zone (40° ± 10° inclination; 15° ± 10° anteversion) were analyzed [9]. To assess the accuracy of the navigation system, absolute differences between the intraoperative values measured by the navigation device and the postoperative values measured by postoperative CT were calculated. Intraoperative loosening of the fixation pins and complications such as pin-site infection, nerve injury, and dislocation were examined.

On the basis of previous data, the difference (mean ± standard deviation) between the image-free navigation and conventional groups of cup anteversion was 7.0 ± 8.7° [10]. The power calculation indicated that 25 cases would be necessary for the study relative to historical controls (α = 0.05, power = 0.8). The intraclass correlation coefficient (ICC) was used to analyze intra-observer and inter-observer reliabilities. All statistical analyses were performed using SPSS version 27 software (SPSS Inc., Chicago, IL). Patients’ demographic characteristics including age and BMI were compared between the two groups using the Mann–Whitney U test. The Chi-squared test and Fisher’s exact test were used to compare sex, diagnosis, and surgical approach. The Mann–Whitney U test was used to compare the absolute values of errors from target angles. The Chi-squared test and Fisher’s exact test were used to compare the percentage of hips within the safe zone and the incidence of complications. Spearman’s rank correlation coefficients were used for correlation analysis of absolute values of navigation error with age and BMI. The Mann-Whitney U test was used to compare navigation error between women and men, OA and the others, Crowe group 1 and Crowe group 2 to 4 [11], and posterior approach and superior approach.

This study was approved by the institutional review board of our hospital, and informed consent was obtained from each patient. All methods were performed in accordance with the Declaration of Helsinki.

On the postoperative CT evaluation, the mean cup inclination was 36.8° ± 3.2° (range, 31° to 46°) in the navigation group and 39.0° ± 10.6° (range, 13° to 60°) in the control group, and the mean cup anteversion was 13.8° ± 5.8° (range, 0° to 27°) in the navigation group and 24.7° ± 9.2° (range, 0° to 41°) in the control group. The intra-observer reliabilities were 0.973 and 0.951 for inclination and anteversion, respectively. The inter-observer reliabilities were 0.962 and 0.942 for inclination and anteversion, respectively. The mean absolute values of errors of the postoperative measured cup inclination and anteversion from the target angles in the navigation group were significantly lower than in the control group (Table 2). The proportion of cups inside Lewinnek’s safe zone was significantly higher in the navigation group than in the control group (94% and 37%, respectively, p < 0.001) (Fig. 2). The mean absolute differences between the values measured by the navigation and the values measured by the postoperative CT (navigation error) were 3.1° ± 2.1° (range, 0° to 9°) in inclination and 4.2° ± 2.8° (range, 0° to 13°) in anteversion (Table 3). There were no significant correlations between navigation error and age or BMI. No significant differences of navigation error were observed between women and men, OA and the others, Crowe group 1 and Crowe group 2 to 4, or posterior approach and superior approach (Table 4). Intraoperative loosening of the fixation pins was not observed. No complications were occurred relative to the navigation procedure. No dislocations occurred in the navigation group. One hip in the control group with the cup position outside the safe zone, 56° in inclination and 36° in anteversion, underwent revision THA due to recurrent dislocation. No significant difference was observed in the dislocation late between the navigation group and control group (0% and 1.5%, respectively, p = 0.316).

Table 2

Absolute values of errors of the measured postoperative angles compared to the target angles
	Navigation group	Control group	P
Inclination (°)	3.9 ± 2.2	8.5 ± 6.9	< 0.001
Anteversion (°)	4.8 ± 3.5	11.4 ± 6.6	< 0.001

Table 3

Absolute values of navigation error
Inclination (°)	3.2 ± 2.1
Anteversion (°)	4.2 ± 2.8

Table 4

Results of statistical analysis of factors affecting navigation error
	Inclination	Anteversion
Gender	p = 0.839	p = 0.157
Age	r=-0.066, p = 0.594	r=-0.11, p = 0.37
Body mass index	r=-0.255, p = 0.036	r=-0.146, p = 0.235
Diagnosis	p = 0.59	p = 0.099
Crowe group	p = 0.492	p = 0.507
Surgical approach	p = 0.642	p = 0.434

Saxler et al reported that only 26% of the acetabular components positioned using the freehand technique were within the safe zone [12]. Hassan et al reported that 58% of the components were positioned inside the safe zone despite using the mechanical alignment guide [13]. Similarly, the percentage of cups inside the safe zone using the mechanical alignment guide was only 37% in the present study. Previous studies reported that image-free large-console navigation systems improved the accuracy of cup positioning compared with the conventional free-hand technique using alignment guides. These studies reported that the percentages of cups inside the safe zone ranged from 80–93% with the navigation and 37–57% with the conventional technique [7, 10, 14, 15]. Although image-free large-console navigation systems can be used without radiation exposure, which is the disadvantage of CT-based navigation systems, the problems of high initial costs remain. Recently, an accelerometer-based portable navigation system (HipAlign, OrthAlign, Aliso Viejo, CA) has been introduced, and studies of its accuracy have been reported. The percentages of cups inside the safe zone were reported to range from 93–100% with the portable navigation [16–21], in contrast to the percentages of 67–93% with the conventional technique [16, 18, 20]. Hasegawa et al reported that the percentages of cups inside the safe zone was 95% with the image-free handheld navigation device in supine position and 67% with conventional technique [22]. Similarly, the present results indicated that the image-free handheld navigation device improved the accuracy of cup insertion compared with the conventional technique (Table 5).

Table 5

Summary of image-free navigation systems in total hip arthroplasty
		Position	Lewinnek’s safe zone		Absolute error from target angle		Navigation error		Dislocation rate
		Position	navigation (%)	conventional technique (%)	inclination (°)	anteversion (°)	inclination (°)	anteversion (°)	navigation (%)	conventional technique (%)
Image-free large console navigation	Kalteis et al. [10]	supine	93	47	3.6	4.2	2.9 ± 2.2	4.2 ± 3.3	0	0.03
	Parratte et al. [14]	supine	80	43	N/A	N/A	4 ± 2.8 (BMI < 27) 3.3 ± 3.06 (BMI ≥ 27)	3.4 ± 3.6 (BMI < 27) 11.6 ± 6.1 (BMI ≥ 27)	0	0
	Lass et al. [15]	supine	90	57	3.0 ± 2.5	5.5 ± 3.6	3.2 ± 2.4	6.5 ± 3.7	N/A	N/A
	Takeda et al. [23]	supine/ lateral	N/A	N/A	N/A	N/A	3.7 ± 2.7	6.8 ± 3.6	0	0
	Naito et al. [7]	supine/ lateral	93	37	3.4 ± 3.0	5.1 ± 3.6	3.3 ± 2.8	5.8 ± 4.9	0.9	1.5
Portable navigation (HipAlign)	Hasegawa et al. [16]	supine	98	67	3.8 ± 2.7	3.3 ± 2.5	3.7 ± 2.8	3.0 ± 2.6	0	0
	Tetsunaga et al. [17]	supine	100	N/A	N/A	N/A	3.3 ± 2.4	3.4 ± 2.2	0	N/A
	Okamoto et al. [18]	supine	99	93	3.1 ± 2.2	2.8 ± 2.3	N/A	N/A	N/A	N/A
	Hayashi et al. [19]	supine	N/A	N/A	2.6 ± 1.9	2.7 ± 2.2	2.7 ± 2.1	2.7 ± 1.8	0	0
	Tanino et al. [20]	lateral	93	67	3.7 ± 3.0	6.0 ± 4.5	N/A	N/A	0	1.8
	Tetsunaga et al. [21]	lateral	N/A	N/A	N/A	N/A	4.1 ± 3.7	6.8 ± 4.8	N/A	N/A
Portable navigation (Naviswiss)	Hasegawa et al. [22]	supine	95	67	4.1 ± 3.2	4.3 ± 3.2	2.8 ± 2.2	2.8 ± 2.0	0	0
	Present study	lateral	94	37	3.9 ± 2.2	4.8 ± 3.5	3.0 ± 2.1	4.3 ± 2.9	0	1.5

Previous studies reported that the navigation error of image-free large-console navigation systems ranged from 2.9° to 3.7° in inclination and 4.2° to 6.8° in anteversion [7, 10, 15, 23]. In the previous studies of portable accelerometer-based navigation systems, the navigation error was reported to range from 2.7° to 4.1° in inclination and 2.7° to 6.8° in anteversion [16, 17, 19, 21]. Hasegawa et al. reported that the navigation error of the image-free handheld navigation device in supine position was 2.8° in inclination and 2.8° in anteversion [22]. The navigation error in the present study was comparable to previous studies (Table 5). Hayashi et al reported that navigation error of both inclination and anteversion were significantly correlated with patients’ BMI in THA using the accelerometer-based portable navigation system in the supine position. The authors mentioned that the incorrect identification of both anterior superior iliac spines (ASISs) due to soft tissue thickness might cause registration errors in obese patients [19]. In the present study, the image-free handheld navigation device in the lateral decubitus position had no need to register the ASISs, and there was no correlation between navigation error and BMI. Furthermore, there were no correlations between navigation error and diagnosis or Crowe group. The deformity might not affect the navigation error because there was no need to register the acetabulum. Surgical approach had no effect on navigation error in the present study. The reason might be that registration was completed before incision.

Previous studies reported that the dislocation rate of THA using image-free large-console navigation systems ranged from 0–0.9%, in contrast to ranging from 0–1.5% using conventional technique [7, 10, 14, 23]. The dislocation rate of THA using the accelerometer-based portable navigation systems was reported to be 0%, in contrast to ranging from 0–1.8% with conventional technique [16, 17, 19, 20]. Hasegawa et al. reported that no dislocations occurred in any hips using the image-free handheld navigation device or conventional technique in supine position [22]. The dislocation rate of the present study was similar to these previous reports (Table 5).

The advantage of the image-free hand-held navigation device was that the incidence of loosening of the pins placed on the iliac crest seems to be low because the tag fixed to the pins was very small and light. There was no case of loosening of the pins in the present study. Tetsunaga et al reported that loosening of Schantz screws occurred in 13% of the cases using the accelerometer-based portable navigation system in the lateral decubitus position, and this was because of jig length and the weight of the navigation system [21].

This study has some limitations. First, the body axis was registered in the lateral decubitus position instead of the FPP. Kanazawa et al reported that the absolute values of change in pelvic tilt in the supine position and lateral decubitus position were 5.0°± 4.1° in the sagittal plane, 5.2°± 4.0° in the axial plane, and 2.8°± 2.3° in the coronal plane [24]. The differences between the body axis and the FPP might have been a cause of navigation error. Registration in the supine position followed by changing to the lateral decubitus position may be one of the methods to resolve this problem. Second, the proportion of surgical approaches was different between the study group and the control group. However, there was no significant difference between the posterior approach and superior approach. This navigation system was useful in the lateral decubitus position regardless of surgical approach. Finally, the clinical outcomes were not investigated. Although the cost was lower than the conventional large console navigation systems and the accuracy of cup insertion improved significantly, it was not clear whether it improved clinical outcomes. Long-term follow-up is necessary to show the clinical advantages.

Use of an image-free hand-held navigation system can improve the accuracy of cup orientation in THA in the lateral decubitus position. No case developed dislocation in the navigation group.

THA: total hip arthroplasty; CT: computed tomography; 3-D: 3-dimensional; BMI: body mass index; OA: osteoarthritis; ONFH: osteonecrosis of the femoral head; RDC: rapidly destructive coxarthrosis; RA: rheumatoid arthritis; FPP: functional pelvic plane; ICC: intraclass correlation coefficient; ASISs: anterior superior iliac spines

Ethics approval and consent to participate

This study was approved by Institutional Review Board at Mie University hospital (No. H2018-083), and informed consent was obtained from all patients.

Consent for publication

Not applicable.

Availability of data and materials

The datasets generated and/or analyzed during the current study are not publicly available due to their containing information that could compromise the privacy of research participants but are available from the corresponding author on reasonable request.

Competing interests

MH is a member of the editorial board (Associate Editor) of this journal. Other authors declare that they have no competing interests.

Funding

The study has not received any external funding.

Authors’ contributions

YN collected the data, analyzed the statistics, and wrote the manuscript. AS performed the surgery and reviewed the manuscript. ST, HW, and MH reviewed the manuscript. All authors read and approved the final manuscript.

Acknowledgments

There are no acknowledgements and no funding was obtained for this study.

D'Lima DD, Urquhart AG, Buehler KO, Walker RH, Colwell CW Jr. The effect of the orientation of the acetabular and femoral components on the range of motion of the hip at different head-neck ratios. J Bone Joint Surg Am. 2000; 82:315-21.
Jolles BM, Zangger P, Leyvraz PF. Factors predisposing to dislocation after primary total hip arthroplasty: a multivariate analysis. J Arthroplasty. 2002;173:282-8.
Kennedy JG, Rogers WB, Soffe KE, Sullivan RJ, Griffen DG, Sheehan LJ. Effect of acetabular component orientation on recurrent dislocation, pelvic osteolysis, polyethylene wear, and component migration. J Arthroplasty. 1998;13:530-4.
Callanan MC, Jarrett B, Bragdon CR, Zurakowski D, Rubash HE, Freiberg AA, et al. The John Charnley Award: risk factors for cup malpositioning: quality improvement through a joint registry at a tertiary hospital. Clin Orthop Relat Res. 2011;469:319-29.
Beckmann J, Stengel D, Tingart M, Götz J, Grifka J, Lüring C. Navigated cup implantation in hip arthroplasty. Acta Orthop. 2009;80:538-44.
Murphy SB. Technique of tissue-preserving minimally-invasive total hip arthroplasty using a superior capsulotomy. Oper Techn Orthop. 2004;14:94-101.
Naito Y, Hasegawa M, Tone S, Wakabayashi H, Sudo A. The accuracy of acetabular cup placement in primary total hip arthroplasty using an image-free navigation system. BMC Musculoskelet Disord. 2021;22:1016.
Murray DW. The definition and measurement of acetabular orientation. J Bone Jt Surg Br. 1993;75:228-32.
Lewinnek GE, Lewis JL, Tarr R, Compere CL, Zimmerman JR. Dislocations after total hip-replacement arthroplasties. J Bone Joint Surg Am. 1978;60:217-20.
Kalteis T, Handel M, Bäthis H, Perlick L, Tingart M, Grifka J. Imageless navigation for insertion of the acetabular component in total hip arthroplasty: is it as accurate as CT-based navigation? J Bone Joint Surg Br. 2006;88:163-7.
Crowe JF, Mani VJ, Ranawat CS. Total hip replacement in congenital dislocation and dysplasia of the hip. J Bone Joint Surg Am. 1979;61:15-23.
Saxler G, Marx A, Vandevelde D, Langlotz U, Tannast M, Wiese M, et al. The accuracy of free-hand cup positioning--a CT based measurement of cup placement in 105 total hip arthroplasties. Int Orthop. 2004;28:198-201.
Hassan DM, Johnston GH, Dust WN, Watson G, Dolovich AT. Accuracy of intraoperative assessment of acetabular prosthesis placement. J Arthroplasty. 1998;13:80-4.
Parratte S, Argenson JNA. Validation and usefulness of a computer-assisted cup-positioning system in total hip arthroplasty: a prospective, randomized, controlled study. J Bone Joint Surg Am. 2007;89:494-9.
Lass R, Kubista B, Olischar B, Frantal S, Windhager R, Giurea A. Total hip arthroplasty using imageless computer-assisted hip navigation: a prospective randomized study. J Arthroplasty. 2014;29:786-91.
Hasegawa M, Naito Y, Tone S, Wakabayashi H, Sudo A. Accuracy of acetabular cup insertion in an anterolateral supine approach using an accelerometer-based portable navigation system. J Artif Organs. 2021;24:82-9.
Tetsunaga T, Yamada K, Tetsunaga T, Sanki T, Kawamura Y, Ozaki T. An accelerometer-based navigation system provides acetabular cup orientation accuracy comparable to that of computed tomography-based navigation during total hip arthroplasty in the supine position. J Orthop Surg Res. 2020;15:147.
Okamoto M, Kawasaki M, Okura T, Ochiai S, Yokoi H. Comparison of accuracy of cup position using portable navigation versus alignment guide in total hip arthroplasty in supine position. Hip Int. 2021;31:492-9.
Hayashi S, Hashimoto S, Takayama K, Matsumoto T, Kamenaga T, Fujishiro T, et al. Evaluation of the accuracy of acetabular cup orientation using the accelerometer-based portable navigation system. J Orthop Sci. 2020;25:612-7.
Tanino H, Nishida Y, Mitsutake R, Ito H. Portable Accelerometer-Based Navigation System for Cup Placement of Total Hip Arthroplasty: A Prospective, Randomized, Controlled Study. J Arthroplasty. 2020;35:172-7.
Tetsunaga T, Yamada K, Tetsunaga T, Furumatsu T, Sanki T, Kawamura Y, et al. Comparison of the accuracy of CT- and accelerometer-based navigation systems for cup orientation in total hip arthroplasty. Hip Int. 2021;31:603-8.
Hasegawa M, Naito Y, Tone S, Sudo A. Accuracy of a novel accelerometer-based navigation (Naviswiss) for total hip arthroplasty in the supine position. BMC Musculoskelet Disord. 2022;23:537.
Takeda Y, Fukunishi S, Nishio S, Fujihara Y, Yoshiya S. Accuracy of Component Orientation and Leg Length Adjustment in Total Hip Arthroplasty Using Image-free Navigation. Open Orthop J. 2017;11:1432.
Kanazawa M, Nakashima Y, Ohishi M, Hamai S, Motomura G, Yamamoto T, et al. Pelvic tilt and movement during total hip arthroplasty in the lateral decubitus position. Mod Rheumatol. 2016;26:435-40.

Competing interest reported. Masahiro Hasegawa is a member of the editorial board (Associate Editor) of this journal. Other authors declare that they have no competing interests.

Download PDF

Version 1

posted

You are reading this latest preprint version

Accuracy of an image-free handheld hip navigation device for total hip arthroplasty in a lateral decubitus position

Status:

Version 1

Abstract

Figures

Background

Materials And Methods

Results

Discussion

Conclusions

Abbreviations

Declarations

References

Additional Declarations

Status:

Version 1