More than a feeling?—Overruling the preoperatively templated offset option leads to a minor offset increase in short stem total hip arthroplasty

Abstract Purpose Short stems are increasingly used in total hip arthroplasty (THA) because of advantages in bone and soft tissue preservation and reconstruction of hip geometry. Digital templating is essential in determining the correct offset option and stem size in THA. However, the preoperative template sizes might be intraoperatively overruled. Patients and methods We evaluated the effect of intraoperative overruling of the preoperatively templated offset option of a short curved stem on hip offset, leg length, implant positioning, and femoral canal fill index. The overruling was performed in case of intraoperative instability, telescoping, or both. A series of 1052 consecutive THAs with a cementless short curved stem and press-fit cup was retrospectively screened. One hundred patients with unilateral THA and a contralateral native and morphologically healthy hip as a reference met the inclusion criteria. Measurements were carried out on preoperative and 3 months anterior–posterior postoperative radiographs. Patients were divided according to the overruling by offset option or stem size. Results Hip offset was increased in all groups, but only with significant increase if an offset option + 1 was used intraoperatively (p = 0.025). LLD was restored without significance in all groups (p = 0.323; p = 0.157). Conclusion Intraoperative overruling of the preoperative digital template in cementless short stem total hip arthroplasty results in an increase of hip offset compared to a contralateral healthy hip. However, the increase is marginal and clearly under 5 mm compared to the contralateral healthy hip.

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High varus stem alignment in short-stem total hip arthroplasty: a risk for reconstruction of femoro-acetabular offset, leg length discrepancy and stem undersizing?

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-021-04176-5 ◽

2021 ◽

Author(s):

Matthias Luger ◽

Julian Stiftinger ◽

Jakob Allerstorfer ◽

Rainer Hochgatterer ◽

Tobias Gotterbarm ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Short Stem ◽

Leg Length ◽

Total Hip ◽

Press Fit ◽

Group A ◽

Leg Length Difference ◽

Group B ◽

Short Stems

Abstract Purpose Short stems are increasingly used in in total hip arthroplasty (THA) because of advantages in bone and soft tissue preservation and reconstruction of hip geometry. Short stems can be inserted in a more varus position compared to conventional straight stems. This poses the risk of final varus misplacement of the femoral component, which is not intended in all femoral short stems. Methods We wanted to evaluate the effect of a high varus stem positioning in MIS THA on hip offset, leg length and femoral canal fill index. A series of 1052 consecutive THAs with a singular cementless femoral short stem and press-fit cup was retrospectively screened for inclusion. One hundred six patients with unilateral THA and a contralateral healthy hip met the inclusion criteria. Measurements were carried out on preoperative and 3 months anterior–posterior postoperative radiographs. Patients were divided into Group A (varus stem alignment ≤ 3°) and Group B (varus stem alignment > 3°). Results Hip offset (HO) increased significantly in Group B by 4 mm (p = 0.013). No influence on leg length difference was detected in both groups. Preoperative CCD angle was significantly lower in Group B (p < 0.001). Canal Fill Indices (CFI) were significantly lower in Group B (CFI I: p < 0.001; CFI II p = 0.003; CF III p = 0.002). Conclusion High varus stem alignment > 3° leads to a statistically significant but minor increase in HO and poses the risk of stem undersizing. A preoperatively low genuine CCD angle pose a risk for varus stem positioning.

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The migration pattern and initial stability of the Optimys short stem in total hip arthroplasty: a prospective 2-year follow-up study of 33 patients with RSA

Hip International ◽

10.1177/1120700020901844 ◽

2020 ◽

pp. 112070002090184 ◽

Cited By ~ 1

Author(s):

Sheryl de Waard ◽

Inger N Sierevelt ◽

Renee Jonker ◽

Daniel Hoornenborg ◽

Harm M van der Vis ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Deep Infection ◽

Migration Pattern ◽

Short Stem ◽

Leg Length ◽

Total Hip ◽

Initial Stability ◽

Short Stems

Background and purpose: The consensus that bone stock preservation and optimal restoration of offset and leg length is important in total hip arthroplasty is now widespread, especially for young and active patients. Short stems seem promising in this aspect, though implant stability is still of concern. This study looked at the migration pattern of the Optimys short stem through RSA analysis. Patients and methods: 40 patients were included. RSA images were made directly postoperatively (within 5 days), at 6 weeks and at 3, 6, 12 and 24 months. Double examinations were made for precision measurement. HOOS and pain scores were obtained preoperatively and at 2 years. 4 patients were excluded due to protocol violation and 1 patient was excluded for RSA analysis with a CN number >110. 2 patients were lost to follow-up after 3 and 6 months ( n = 1 lost, n = 1 deep infection, respectively). Results: Mean age was 60 years with a mean BMI of 27. RSA analysis of 34 patients showed a significant initial median proximodistal translation (subsidence) of 0.21 mm (IQR 0.64–0.06) and anteversion-retroversion rotation of 0.59° (IQR 0.01–1.34) at 6 weeks, after which the stem stabilises and showed no further significant movement. Median migration in other directions was small. 4 patients had an initial subsidence of >2 mm, all showed secondary stabilisation. HOOS outcomes were satisfactory, with the domain symptoms and pain showing a median score of 95/100 at 2 years. Conclusions: After initial migration the Optimys achieves secondary stabilisation, suggesting low risk on long-term aseptic loosening. Clinical trials registration: NL47055.048.13.

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The Influence of Tribological Pairings and Other Factors on Migration Patterns of Short Stems in Total Hip Arthroplasty

BioMed Research International ◽

10.1155/2017/8756432 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Thilo Floerkemeier ◽

Michael Schwarze ◽

Christof Hurschler ◽

Jens Gronewold ◽

Henning Windhagen ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Three Dimensions ◽

Short Stem ◽

Acetabular Cup ◽

Bone Contact ◽

Stem Size ◽

Total Hip ◽

Bearing Couple ◽

Short Stems

Over the last decade, the number of short stem total hip arthroplasty procedures has increased. Along with the possible benefits associated with short stems is a smaller implant-bone contact surface, which may have a negative influence on primary stability and impair osseointegration. Previous studies observed migration of short stems, especially within the first three months. The variables that influence migration in short stem hip implants remain unknown. Therefore, the purpose of this study was to associate the migration of short stems with its possible influencing variables. Migration data from two different short stem studies were retrospectively analyzed. Migration within the first two postoperative years was determined by model-based Roentgen stereophotogrammetric analysis. Migration was correlated to bearing couple, type and size of stem, size of acetabular cup, and age, gender, weight, and height of patients using a multiple factor analysis. Eigenvalue analysis explained 80.7% of the overall variance for the first three dimensions. The four most dominant variables in the first dimension were weight, stem size, acetabular cup size, and patient height (correlations of 0.81, 0.80, 0.71, and 0.70, resp.). None of the analyzed parameters (bearing couple, type and size of stem, size of acetabular cup, and age, gender, weight, and height of patients) affected the migration pattern of short stem THA with primary metaphyseal fixation.

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Primary stability of calcar-guided short-stem total hip arthroplasty in the treatment of osteonecrosis of the femoral head: migration analysis using EBRA-FCA

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-020-03610-4 ◽

2020 ◽

Vol 140 (12) ◽

pp. 2091-2100

Author(s):

Yama Afghanyar ◽

Christoph Danckwardt ◽

Miriam Schwieger ◽

Uwe Felmeden ◽

Philipp Drees ◽

...

Keyword(s):

Femoral Head ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Migration Pattern ◽

Short Stem ◽

Stem Design ◽

Total Hip ◽

Migration Analysis ◽

Short Stems

Abstract Introduction Osteonecrosis of the femoral head (ONFH) is a disabling condition that often results in secondary arthritis necessitating total hip arthroplasty (THA). Short-stem THA has constantly gained popularity. It remains controversial, whether ONFH represents a risk factor for failure after the implantation of short stems with pronounced metaphyseal anchorage. The potential spread of the osteonecrotic area and bone marrow edema into the metaphyseal bone might result in compromised stability. Early implant migration is considered predictive of subsequent aseptic loosening. The purpose of this study was a migration analysis of a modern, calcar-guided short-stem implant in patients with ONFH in a mid-term follow-up. Materials and methods This retrospective analysis investigated the migration pattern of 45 calcar-guided short stems in patients with ONFH, using Einzel-Bild-Roentgen-Analyse Femoral-Component-Analysis (EBRA-FCA). Influencing factors such as ARCO categories, age, gender, body weight and BMI were analyzed. Complications and adverse events were documented. Results At mid-term [48.1 months (SD 20.7 months)], mean axial migration was 1.56 mm (SD 1.77 mm). Mean migration rate stabilized after 2 years. No influence of ARCO categories, age and BMI was found. A tendency of increased axial migration was observed in male patients and in overweight patients. No revision surgeries had to be performed during follow-up. Conclusion The results indicate a migration pattern comparable to that of primary osteoarthritis patients with slight initial migration under full load followed by subsequent stabilization in the metaphyseal femur. The 100% survival rate at mid-term supports the usage of this short-stem design in patients with ONFH.

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The accuracy of digital templating in cementless total hip arthroplasty in dysplastic hips

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04793-6 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Emelie Kristoffersson ◽

Volker Otten ◽

Sead Crnalic

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Femoral Stem ◽

Developmental Dysplasia ◽

Leg Length ◽

Acetabular Cup ◽

Digital Templating ◽

Total Hip ◽

Implant Size ◽

Crowe Classification

Abstract Background Total hip arthroplasty (THA) for developmental dysplasia of the hip (DDH) is a complex procedure due to associated anatomical abnormalities. We studied the extent to which preoperative digital templating is reliable when performing cementless THA in patients with DDH. Methods We templated and compared the pre- and postoperative sizes of the acetabular and femoral components and the center of rotation (COR), and analysed the postoperative cup coverage, leg length discrepancy (LLD), and stem alignment in 50 patients (56 hips) with DDH treated with THA. Results The implant size exactly matched the template size in 42.9% of cases for the acetabular component and in 38.2% of cases for the femoral component, whereas the templated ±1 size was used in 80.4 and 81.8% of cases for the acetabular and femoral components, respectively. There were no statistically significant differences between templated and used component sizes among different DDH severity levels (acetabular cup: p = 0.30 under the Crowe classification and p = 0.94 under the Hartofilakidis classification; femoral stem: p = 0.98 and p = 0.74, respectively). There were no statistically significant differences between the planned and postoperative COR (p = 0.14 horizontally and p = 0.52 vertically). The median postoperative LLD was 7 (range 0–37) mm. Conclusion Digital preoperative templating is reliable in the planning of cementless THA in patients with DDH.

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The Accuracy and Ability of Preoperative Templating to Restore Femoral Offset in Calcar-Guided Short-Stem Total Hip Prosthesis through Direct Anterior Approach

The Journal of Hip Surgery ◽

10.1055/s-0041-1729867 ◽

2021 ◽

Author(s):

Barbara Favier ◽

Nathalie van Beek ◽

Mike Tengrootenhuysen

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Anterior Approach ◽

Direct Anterior Approach ◽

Short Stem ◽

Size Difference ◽

Femoral Offset ◽

Stem Size ◽

Total Hip ◽

Preoperative Templating

AbstractThe aim of this study was to assess the applicability and ability of preoperative templating to restore femoral offset and hip length with a calcar-guided short-stem implant design in total hip arthroplasty through the direct anterior approach. Preoperative measurements were performed of femoral offset, hip length, and stem size and compared with the perioperative placed prosthesis in 100 patients undergoing primary total hip replacement through direct anterior approach. Additionally, the pre- and postoperative femoral offset and hip length were compared to evaluate the ability to restore the offset and hip length with this kind of femoral short stem. With an acceptance of 1 size difference pre- and postoperatively, a 94% accuracy of predicting the size of the calcar-guided short stem was achieved with templating. Femoral offset was within means of 5 mm in 82.2% of the patients. Postoperative hip length was within 6 mm in 90% of the patients compared with the preoperative length.The use of preoperative templating for total hip arthroplasty with calcar-guided short-stem implants was proven to be a useful tool to predict the definite implanted size of the femoral prosthesis. Our results show that this new stem design does not significantly differ from previous reported outcomes with other stem designs and is competent to restore the femoral offset and hip length within clinical acceptable range. Level of evidence Level 3 retrospective case study.

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Short versus conventional stem in cementless total hip arthroplasty

Der Orthopäde ◽

10.1007/s00132-021-04083-y ◽

2021 ◽

Vol 50 (4) ◽

pp. 296-305

Author(s):

Arnd Steinbrück ◽

Alexander W. Grimberg ◽

Johanna Elliott ◽

Oliver Melsheimer ◽

Volkmar Jansson

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Joint Infection ◽

Short Stem ◽

Cumulative Probability ◽

Term Survival ◽

Total Hip ◽

Survival Difference ◽

Significant Difference ◽

Short Stems

Abstract Background Short-stemmed total hip arthroplasty (THA) is well established and gaining popularity in Germany. The perception that short stems may predispose to primary instability in the femur has resulted in a more thorough follow-up of younger patient cohorts than the typical uncemented THA population. To address this issue, an evidence-based approach is presented for a retrospective mid-term survival analysis of a large registry-based cohort in primary cementless THA comparing short stems with a matched group of conventional stems. Material and methods Propensity score matching (PSM, see Infobox 1) was used on 131,580 primary cementless THAs fulfilling the inclusion criteria performed between November 2012 and September 2019 and the cumulative probability of revision (CPR) of short and conventional stems for any reason, for reasons excluding prosthetic joint infection (PJI), and due to PJI were compared. Results After PSM at 1:1 balanced groups of 17,526 short stems and of 17,526 conventional stems were achieved demonstrating no significant difference for CPR for any reason and for reasons excluding PJI. Matched CPR for any reason was 2.9% (95% confidence interval, CI, 2.4–3.5%) 5 years after primary THA in the short stem and 3.1% (95% CI 2.7–3.4%) in the conventional stem group. The CPR excluding PJI was 2.2% (95% CI 1.7–2.7%) vs. 2.1% (95% CI 1.8–2.4%). In contrast, the incidence of PJI was statistically significant lower for short stems. Conclusion For the considered period, there was no statistically significant survival difference in uncemented THA between comparison groups but a lower incidence for PJI in short-stem THA. Further analyses of registry data are required to rule out range of indications and late mechanical failure of short stems.

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Low rate of early periprosthetic fractures in cementless short-stem total hip arthroplasty using a minimally invasive anterolateral approach

Journal of Orthopaedics and Traumatology ◽

10.1186/s10195-021-00583-x ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Matthias Luger ◽

Günter Hipmair ◽

Clemens Schopper ◽

Bernhard Schauer ◽

Rainer Hochgatterer ◽

...

Keyword(s):

Risk Factors ◽

Total Hip Arthroplasty ◽

Minimally Invasive ◽

Hip Arthroplasty ◽

Supine Position ◽

Short Stem ◽

Anterolateral Approach ◽

Total Hip ◽

Asa Score ◽

Short Stems

Abstract Purpose Minimally invasive (MIS) approaches in combination with short stems have gained popularity in recent years in total hip arthroplasty (THA). A decreased risk for periprosthetic femoral fractures (PFFs) is reported for cementless short-stem THA, but in contrast to other approaches, the risk factors for PFFs for short-stem THA using MIS anterolateral approach in supine position are not described in literature. Methods A single-center consecutive series of 1052 hips in 982 patients, performed between 2014 and 2019 with a short curved stem and a press fit using an MIS anterolateral approach in supine position, was retrospectively screened for inclusion. Fourteen patients were lost to follow-up. Therefore, 1038 THAs in 968 patients were included. Risk factors for intra- and postoperative PFFs within 90 days were analyzed. We investigated for sex, age, body mass index (BMI), diagnosis, and laterality. Results In total, 18 PFFs (1.7%) occurred. Intraoperative fracture occurred in ten cases ( 0.9%), with another eight cases (0.8%) occurring postoperatively. Increased American Society of Anesthesiologists (ASA) Score was a significant risk factor for PFF (p = 0.026), whereas sex (p = 0.155), age (p = 0.161), BMI (p = 0.996), and laterality (p = 1.000) were not. Seven PFFs (0.7%) required revision arthroplasty. Conclusion Cementless short-stem THA using the MIS anterolateral approach is a procedure with a low number of PFFs within 90 days from index surgery. Fracture rates are comparable to other MIS approaches, and comparable femoral short stems are used. Age, sex, and BMI were not identified as risk factors of PFF, while risk for PFF increased with ASA Score. Level of Evidence Level IV

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Retrospective Clinical and Radiological Outcomes of Total Hip Arthroplasty in 51 Patients After a Mean 8.2 Years Using the Nanos® Short-stem Prosthesis

Surgical Technology Online ◽

10.52198/21.sti.39.os1473 ◽

2021 ◽

Vol 39 ◽

Author(s):

Christian Fischer ◽

◽

Julia Dietz ◽

Karl-Stefan Delank ◽

Alexander Zeh ◽

...

Keyword(s):

Patient Satisfaction ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Survival Rates ◽

Short Stem ◽

Harris Hip Score ◽

Leg Length ◽

Total Hip ◽

The Mean

Introduction: Over the past several years, femoral short-stem hip implants have become more popular as a treatment option in the field of primary hip arthroplasty for younger and more active patients. Current data on clinical outcomes and the implant survival rates in patients with short-stem implants cover a maximum of five to six years. The aim of this study was to assess the survival rates, as well as clinical and functional outcomes, in total hip arthroplasty (THA) using the Nanos® short-stem implant (Smith & Nephew, Marl, Germany) over a follow-up period exceeding 5 y. Materials and Methods: This single-center retrospective study included the first 100 patients who were treated at the Department of Orthopedics at the University Hospital Halle (Saale) between January 2008 and February 2009. Ultimately, the complete data of 51 patients (54 hips) were reviewed. The follow-up period was from May to November 2017. We evaluated patient satisfaction regarding pain and function using a grading system. The Harris Hip Score and Forgotten Joint Score were obtained to evaluate functional outcome after THA. Postoperative radiographic evaluation included the measurement of leg-length discrepancy, changes in the shaft axis, femoral offset and horizontal or vertical center of rotation. Potential postoperative shaft angulation or axial shaft migration was also determined. Radiographic images were checked for radiolucent lines and heterotopic ossification using the classification systems outlined by Green and Brooker. Results: The average follow-up was 97.8 months (8.2 y). The mean patient age at follow-up was 68 y and the body mass index was 28.2 kg/m2. The mean Harris hip score at follow-up was 92.0 and the Forgotten Joint Score was 91.7 %. Survey results showed that patient satisfaction and pain perception were rated very good. No significant change in leg length was observed (mean: 0.1 mm shortening). Overall, a rather varus stem positioning was detected postoperatively (mean: 3.1°). The femoral offset was slightly reduced on average in the entire patient group (mean: -1.8 mm). In the horizontal plane, lateralization of the center of rotation was detected overall (mean: 0.7 mm). In the vertical plane, cranialization was noted (mean: 1.4 mm). The CCD angle did not change. There was no further stem migration postoperatively. Radiolucent lines occurred in 10 cases in Gruen zones 1 and 7. Heterotopic ossification occurred in stages 1 to 3 according to the Brooker classification system. We found no cases of aseptic loosening or other reasons for revision. Conclusion: The outcomes after a mean follow-up of 97.8 months (8.2 y) showed that high levels of patient satisfaction and functional outcome can be achieved with the use of a short-stem endoprosthesis. Sufficient restoration of the patient's individual anatomy paired with high survival rates makes this short-stem prosthesis a reliable implant in total hip arthroplasty.

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