Comparative repeatability of guide-pin axis positioning in computer-assisted and manual femoral head resurfacing arthroplasty

2007 ◽  
Vol 221 (7) ◽  
pp. 713-724 ◽  
Author(s):  
A Hodgson ◽  
N Helmy ◽  
B A Masri ◽  
N V Greidanus ◽  
K B Inkpen ◽  
...  
Keyword(s):  
Femoral Head ◽  
Computer Assisted Surgery ◽  
Hip Resurfacing ◽  
Computer Assisted ◽  
Comparable Amount ◽  
Hip Resurfacing Arthroplasty ◽  
Resurfacing Arthroplasty ◽  
Surgeon Experience ◽  
Position And Orientation ◽  
Version Measurement

The orientation of the femoral component in hip resurfacing arthroplasty affects the likelihood of loosening and fracture. Computer-assisted surgery has been shown to improve significantly the surgeon's ability to achieve a desired position and orientation; nevertheless, both bias and variability in positioning remain and can potentially be improved. The authors recently developed a computer-assisted surgical (CAS) technique to guide the placement of the pin used in femoral head resurfacing arthroplasty and showed that it produced significantly less variation than a typical manual technique in varus/valgus placement relative to a pre-operatively determined surgical plan while taking a comparable amount of time. In the present study, the repeatability of both the CAS and manual techniques is evaluated in order to estimate the relative contributions to overall variability of surgical technique (CAS versus manual), surgeon experience (novice versus experienced), and other sources of variability (e.g. across specimens and across surgeons). This will enable further improvements in the accuracy of CAS techniques. Three residents/fellows new to femoral head resurfacing and three experienced hip arthroplasty surgeons performed 20-30 repetitions of each of the CAS and manual techniques on at least one of four cadaveric femur specimens. The CAS system had markedly better repeatability (1.2°) in varus/valgus placement relative to the manual technique (2.8°), slightly worse repeatability in version (4.4° versus 3.2°), markedly better repeatability in mid-neck placement (0.7 mm versus 2.5 mm), no significant dependence on surgeon skill level (in contrast to the manual technique), and took significantly less time (50 s versus 123 s). Proposed improvements to the version measurement process showed potential for reducing the standard deviation by almost two thirds. This study supports the use of CAS for femoral head resurfacing as it is quicker than the manual technique, independent of surgeon experience, and demonstrates improved repeatability.

scholarly journals No added value for Computer-Assisted surgery to improve femoral component positioning and Patient Reported Outcomes in Hip Resurfacing Arthroplasty; a multi-center randomized controlled trial

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
M. C. Koper ◽  
M. Reijman ◽  
E. M. van Es ◽  
J. H. Waarsing ◽  
H. W. J. Koot ◽  
...  
Keyword(s):  
Randomized Controlled Trial ◽  
Femoral Component ◽  
Controlled Trial ◽  
Computer Assisted Surgery ◽  
Hip Resurfacing ◽  
Added Value ◽  
Computer Assisted ◽  
Hip Resurfacing Arthroplasty ◽  
Resurfacing Arthroplasty ◽  
Randomized Controlled

Abstract Background Computer Assisted Surgery (CAS) has proven to improve the accuracy in several orthopedic procedures. Therefore we used this technique to evaluate femoral component positioning in Hip Resurfacing Arthroplasty (HRA). The aim of this study was to evaluate imageless CAS compared to manually implanted femoral components and subsequently evaluates Patient Related Outcome Measures (PROMs). We hypothesized that the use of CAS optimizes the position of the femoral component and improves PROMs. Methods This is a multicenter, single-blinded, randomized, controlled trial of two groups. In the CAS group guiding of the femoral component was done with imageless navigation. In the Conventional (control) group the femoral component was placed manually according to the preplanned position. The primary outcome measure consists of a maximum of 3 degrees difference between the postoperative Stem Shaft Angle (SSA) and preplanned SSA. Secondary outcome measures consist of the Hip disability and Osteoarthritis Outcome Scale (HOOS), the Harris Hip Score (HHS) and Visual Analogue Scale (VAS) pain score. Results A total of 122 patients were randomized, 61 in the CAS group and 61 in the conventional group. There was no significant differences in accuracy of femoral implant position. The mean difference between the postoperative- and preplanned SSA was − 2.26 and − 1.75 degrees (more varus) respectively in the CAS and Conventional group. After surgery both groups show significant improvement in all PROMs compared to the baseline measurements, with no significant differences between the groups. Conclusion Our cohort indicates no benefit for the use of CAS in accuracy of placement of the femoral component in HRA compared to manual implantation. There are no clinical differences in PROMs after 1 year follow up. This study showed no added value and no justification for the use of CAS in femoral component positioning in HRA. Trial registration This trial is registered at ClinicalTrails.gov (https://clinicaltrials.gov/) on the 25th of October 2006: NCT00391937. Level of incidence Level IIb, multicenter randomized controlled trial.

Computer-Assisted Hip Resurfacing Arthroplasty

2010 ◽  
Vol 25 (1) ◽  
pp. 50-55
Author(s):  
Jinal Choudhari ◽  
Jason D. Kinkartz ◽  
Michael L. Swank
Keyword(s):  
Hip Resurfacing ◽  
Computer Assisted ◽  
Hip Resurfacing Arthroplasty ◽  
Resurfacing Arthroplasty

Results of a Stemmed Bone Ingrowth HIP Resurfacing Arthroplasty in the Canine

1985 ◽  
Vol 55 ◽  
Author(s):  
W. C. Kim ◽  
H. Rechl ◽  
H. C. Amstutz ◽  
K. Hermens ◽  
P. F. O'Carroll ◽  
...  
Keyword(s):  
Femoral Head ◽  
Femoral Neck ◽  
Bone Ingrowth ◽  
Stress Shielding ◽  
Load Sharing ◽  
Hip Resurfacing ◽  
Hip Resurfacing Arthroplasty ◽  
Resurfacing Arthroplasty ◽  
Compressive Stresses ◽  
Acetabular Components

ABSTRACTA stemmed bone ingrowth hip resurfacing arthroplasty designed for use with bone deficient femoral heads raises concerns of stress shielding and is investigated in this study. Ten CoCr bone ingrowth hip resurfacing devices were implanted in five adult canines. Design consisted of a 6mm deep cylindrical cavity with porous beaded surface of 150um pore size and Imm nominal depth. A 3mm diameter smooth CoCr stem was eccentrically fixed to the component for additional fixation with threaded nut at the lateral cortex. Femoral head was reamed for interference fit with hole for the stem placed superiorly. Acrylic fixed polyethylene cups were used for acetabular components. Animals were followed with serial radiographs to sacrifice at 73 to 267 days. After sacrifice microradiographs of ground sections and histologic specimens were evaluated for bone ingrowth, remodeling, and femoral neck attenuation. All specimens showed well ingrown bone at the porous layer. Bone remodeling showed preservation of proximal femoral neck cancellous trabecular pattern and medial cortical support. Resorption of bone at the implant rim and femoral neck thinning were, however, present. Two specimens had neck thinning of 10% or less, four of 10 to 25%, three of 25 to 50%, and one greater than 50%. There was no correlation with time to sacrifice for parameters evaluated. Results indicate preservation of the compressive stresses through the femoral head. Resorption of bone at the rim and femoral neck attenuation, however, indicates load sharing between the implant and bone. Though a lower modulus material such as titanium would decrease load sharing, the geometrical design insures the presence of stress distribution anomalies.

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