Wagner Cone Research Articles

Adjustment of stem anteversion using tapered cone stem in total hip arthroplasty.

The aim of this study was to evaluate the suitability of the tapered cone stem in total hip arthroplasty (THA) in patients with excessive femoral anteversion and after femoral osteotomy. We included patients who underwent THA using Wagner Cone due to proximal femur anatomical abnormalities between August 2014 and January 2019 at a single institution. We investigated implant survival time using the endpoint of dislocation and revision, and compared the prevalence of prosthetic impingements between the Wagner Cone, a tapered cone stem, and the Taperloc, a tapered wedge stem, through simulation. We also collected Oxford Hip Score (OHS), visual analogue scale (VAS) satisfaction, and VAS pain by postal survey in August 2023 and explored variables associated with those scores. Of the 58 patients (62 hips), two (two hips) presented with dislocation or reoperation, and Kaplan-Meier analysis indicated a five-year survival rate of 96.7% (95% CI 92.4 to 100). Mean stem anteversion was 35.2° (SD 18.2°) for the Taperloc stem and 29.8° (SD 7.9°) for the Wagner Cone stem; mean reduction from Taperloc to Wagner Cone was 5.4° (SD 18.8°). Overall, 55 hips (52 patients) were simulated, and the prevalence of prosthetic impingement was lower for the Wagner Cone (5.5%, 3/55) compared with the Taperloc (20.0%, 11/55) stem, with an odds ratio of 0.20 (p = 0.038). Among the 33 respondents to the postal survey (36 hips), the mean scores were VAS pain 10.9, VAS satisfaction 86.9, and OHS 44.7. A multivariable analysis revealed that reduction of stem anteversion from Taperloc to Wagner Cone was more favourable for VAS pain (p = 0.029) and VAS satisfaction (p = 0.002). The mid-term survival rate for THA using the Wagner Cone stem was high, which may be supported by a reduction in prosthetic impingement. The reduction in excessive stem anteversion by using a tapered cone stem was associated with reduced pain and increased patient satisfaction.

The Wagner Cone Stem for Atypical Femoral Anatomy in Total Hip Arthroplasty: A Report of 320 Cases with Minimum 5-Year Follow-up.

The Wagner Cone Prosthesis was designed to address complex femoral deformities during total hip arthroplasty (THA), but its mid-term component survivorship and functional outcomes remain undetermined. The objectives of this study were to determine the implant survivorship, patient satisfaction, functional outcomes, osseointegration as seen radiographically, implant subsidence, and complications of THA using the Wagner Cone Prosthesis stem at intermediate-term follow-up. This study involved 302 patients with proximal femoral deformities, including developmental hip dysplasia and Legg-Calvé-Perthes disease, who underwent a total of 320 primary THAs using the Wagner Cone Prosthesis. The average age at the time of surgery was 49.4 ± 14.5 years (range, 18.8 to 85.6 years). Patient satisfaction was recorded using a self-administered questionnaire assessing satisfaction in 4 domains. The University of California at Los Angeles (UCLA) activity score, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Oxford Hip Score (OHS), the Forgotten Joint Score (FJS), radiographic outcomes, and complications were recorded. The mean follow-up time was 10.1 years (range, 5.2 to 15.5 years). Survivorship of the Wagner Cone Prosthesis was 98.7% (95% confidence interval [CI]: 97.2% to 100%) with stem revision as the end point and 95.8% (95% CI: 93.5% to 98.2%) with reoperation for any reason as the end point at 10 years postoperatively. In total, 3 stems were revised: 2 for infection and 1 for chronic hip dislocation. The median patient satisfaction score was 95 (interquartile range [IQR], 80 to 100), median UCLA score was 6 (IQR, 6 to 7), median WOMAC score was 18 (IQR, 16 to 22), median OHS was 40 (IQR, 36 to 47), and median FJS was 80 (IQR, 76 to 88) at the time of final follow-up. All Wagner Cone stems that were not revised showed radiographic evidence of osseointegration, with a mean stem subsidence of 0.9 ± 0.8 mm at the most recent follow-up. The use of the Wagner Cone Prosthesis stem in patients with complex femoral anatomy undergoing primary THA is associated with excellent component survivorship, high levels of patient satisfaction, good functional outcomes, and reliable osseointegration with minimal stem subsidence as seen on radiographs at intermediate-term follow-up. Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Accurate Preoperative Digital Planning: The First Mandatory Step to Success in Complex and Unusual Total Hip Arthroplasties: Commentary on an article by Babar Kayani, MBBS, BSc, FRCS(Tr&Orth), PhD, et al.: "The Wagner Cone Stem for Atypical Femoral Anatomy in Total Hip Arthroplasty. A Report of 320 Cases with Minimum 5-Year Follow-up".

Accurate Preoperative Digital Planning: The First Mandatory Step to Success in Complex and Unusual Total Hip Arthroplasties: Commentary on an article by Babar Kayani, MBBS, BSc, FRCS(Tr&Orth), PhD, et al.: "The Wagner Cone Stem for Atypical Femoral Anatomy in Total Hip Arthroplasty. A Report of 320 Cases with Minimum 5-Year Follow-up".

Is step-cut shortening osteotomy a better choice than transverse osteotomy for total hip arthroplasty for Crowe type III-IV hip dysplasia?

IntroductionTotal hip arthroplasty for developmental hip dysplasia is a challenging surgery due to anatomic abnormalities. Crowe III and Crowe IV hip dysplasia generally necessitates a subtrochanteric shortening osteotomy. Transverse and step-cut osteotomy are the most common procedures for shortening of femur although there is still no consensus which one is a superior method. The objective of this study was to demonstrate whether transverse or step-cut osteotomy is superior in hips who undergo arthroplasty for high riding hip dysplasia. HypothesisOur hypothesis was that higher rates of union would be achieved in patients with Crowe III-IV hip dysplasia when the step-cut osteotomy was performed compared to transverse osteotomies. Material and methodsA total of 99 hips from 90 patients (9 bilateral, 81 unilateral; 79 female, 11 male), each with a minimum follow-up duration of two years, were included in this study. The hips were classified as Crowe III (n=16) or IV (n=83). All hips were implanted cementless. Transverse or step-cut osteotomy was chosen for osteotomy type. The clinical and functional outcomes were assessed using the Harris Hip Score (HHS), limb length discrepancy (LLD), and limping. The complications and management of these were noted. The union rates were compared between osteotomy types. ResultsThe mean age at surgery was 48.8 (range, 21–79 years). The follow-up period was 64.3 months in average (range, 24 to 192 months). The mean Harris Hip Score before surgery was 35.6 (range, 18–50), and increased to 88.1 (range, 61–98) points at the most recent follow-up. The preoperative leg length discrepancy (LLD) measured 5.3cm (with a range of 3 to 6.8), while the postoperative LLD reduced to 0.8cm (with a range of 0 to 1.6). There were a total of 38 complications in 35 patients out of 99 cases, resulting in a complication rate of 38.4%. The most frequent complication observed was intraoperative femoral fractures, occurring in 13 cases. Residual limping was seen in 73.7% of all. Step-cut osteotomy was performed in 64 hips (35 CDH stem [Zimmer Biomet, Warsaw, IN, USA], 29 Wagner Cone stem [Zimmer Biomet, Warsaw, IN, USA]) and, transverse in 35 hips (22 CDH, 13 Wagner Cone). Six hips had nonunion problem and all of them were operated with a step-cut osteotomy (z-score: –7.12 and p<0.00001, Mann-Whitney U Test). ConclusionTransverse osteotomy may be a better option while performing a shortening subtrochanteric level osteotomy for total hip arthroplasty for Crowe III-IV hips. Level of evidenceLevel III; observational retrospective cohort study.

Three-dimensional femur morphology analysis for the optimal location of subtrochanteric osteotomy with an implanted Wagner cone stem in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip

BackgroundThis study aimed to accurately evaluate the matching of proximal and distal femoral segments and fitting of the femur–femoral stem in patients with Crowe type IV developmental dysplasia of the hip (DDH) who have undergone subtrochanteric osteotomy at different locations with an implanted Wagner cone stem to improve the rate of the bone union at the osteotomy site.MethodsThree-dimensional femur morphology of 40 patients with Crowe type IV DDH was evaluated at each cross-section to determine the femoral cortical bone area. This study focused on five osteotomy lengths (2.5, 3, 3.5, 4, and 4.5 cm). The overlapped area between the proximal and distal cortical bone segments was defined as the contact area (S, mm2), and the contact area to distal cortical bone area ratio was defined as the coincidence rate (R). Three indicators were used to evaluate the matching and fitting of the osteotomy sites with the implanted Wagner cone stems: (1) higher S and R between the proximal and distal segments; (2) the effective fixation length of the femoral stem at the distal segments being at least 1.5 cm; and (3) osteotomy did not involve the isthmus.ResultsIn all groups, S significantly decreased in the two proximal levels above the 0.5 cm level below the lesser trochanter (LT) compared with those below this level. In comparison, at osteotomy lengths from 2.5 to 4 cm, R significantly decreased in the three proximal levels. The optimal osteotomy levels ranged from 1.5 and 2.5 cm below the LT for an appropriately sized stem.ConclusionsSubtrochanteric osteotomy at the optimal level not only ensures fitting of the femur–femoral stem but also meets the requirements of a higher S and R to ensure adequate reduction and stabilization at the osteotomy site, which may contribute to the bone union. Although the optimal osteotomy level varies with the size of the femoral stem and the length of the subtrochanteric osteotomy, the optimal osteotomy levels for an appropriately sized Wagner cone femoral stem implantation range from 1.5 to 2.5 cm below the LT.

Outcome of the Wagner Cone femoral component for difficult anatomical conditions during total hip arthroplasty.

Total hip arthroplasty (THA) in patients with small or unusual proximal femoral anatomy is challenging due to sizing issues, control of version, and implant fixation. The Wagner Cone is a monoblock, fluted, tapered stem with successful outcomes for these patients; however, there is limited information on subsidence, a common finding with cementless stems. We retrospectively reviewed our cases using the modified Wagner Cone (Zimmer, Warsaw, IN) implanted over a 13-year period (2006-2019) in patients with small or abnormal proximal femoral anatomy. We performed 144 primary THAs in 114 patients using this prosthesis. Mean follow-up was 4.5 ± 3.4years (range, 1-13years). Common reasons for implantation were hip dysplasia (52%) and osteoarthritis in patients with small femoral proportions (22%). Analysis of outcomes included assessment of stem subsidence and stability. Survival was 98.6% in aseptic cases; revision-free survival was 97.9%. Femoral subsidence occurred in 84 cases (58%). No subsidence progressed after 3months. Of those that subsided, the mean distance was 2.8 ± 2.0mm. There was less subsidence in stems that stabilized prior to sixweeks (2.2 ± 1.4mm) compared to those that continued until 12weeks (3.9 ± 1.6, p = 0.02). Harris Hip, UCLA, and WOMAC scores significantly improved from pre-operative evaluation (p < 0.001*, p < 0.003*, p ≪ 0.001*); there was no difference in outcome between patients with and without subsidence (p = 0.430, p = 0.228, p = 0.147). The modified Wagner Cone demonstrates excellent clinical outcomes in patients with challenging proximal femoral anatomy. Subsidence is minor, stops by 3months, and does not compromise clinical outcome.

Mid-term outcomes of the Wagner Cone Prosthesis™ stem for developmental dysplasia of the hip: minimum twoyear follow-up.

Treatment of symptomatic developmental dysplasia of the hip (DDH) requires a technically demanding total hip arthroplasty (THA) reconstruction. In patients with DDH, prostheses can be difficult to implant and often face the risk of fracture, mismatch, and loosening. The Wagner Cone Prosthesis™ is a tapered, conical stem which can improve treatment success in this population. We look at midterm survivorship and outcomes of THA for DDH using the Wagner Cone Prosthesis™. We retrospectively analyzed 28 patients (33 hips) with DDH undergoing THA using the Wagner Cone Prosthesis™ between January 2008 and January 2020. Ten, nine, and fourteen included patients were classified as Hartofilakidis A, B, and C, respectively. Survivorship according to Kaplan-Meier analysis was the primary outcome, with re-operation and revision as endpoints. The Oxford hip score (OHS) was used to assess clinical outcome. We used multivariate analysis to determine predictors of poor outcomes. The average follow-up was 4.6years, with a minimum of twoyears. Kaplan-Meier survivorship over the 13-year study period was 93.9 ± 4.2% for all-cause revision as an endpoint and 96.9 ± 3.1% for stem revisions only. The overall reoperation rate was 6.1%, with periprosthetic fracture and dislocation being reasons for re-operation. No patients were revised for aseptic loosening, and no patients were revised for subsidence. OHS improved from 19.3 ± 9.6 (4-39) pre-operatively to 37.6 ± 8.4 (19-48) at latest follow-up (p < 0.05). In patients with DDH, THA with the Wagner Cone Prosthesis™ demonstrates excellent clinical, radiographic, and patient-reported functional outcomes at midterm follow-up.

Stay Short or Go Long in Revision Total Hip Arthroplasty With Paprosky Type II Femoral Defects: A Comparative Study With the Use of an Uncemented Distal Fixating Modular Stem and a Primary Monobloc Conical Stem With 5-Year Follow-Up

BackgroundIn the revisions for Paprosky type II femoral defects, diaphyseal fixating femoral stems are commonly used. To preserve bone stock, the use of a shorter primary conical stem could be an adequate alternative. The objective of this study is to compare the results of a primary conical stem to the more commonly used diaphyseal fixating modular revision stem in revision total hip arthroplasty surgery with Paprosky type II femoral defects. MethodsA total of 59 consecutive patients with Paprosky type II femoral defects from our prospective revision registry were included. Thirty patients who received a long distal fixating modular stem (Revision Stem, Lima Corporate) and 29 patients who received a primary conical short stem (Wagner Cone, Zimmer) were prospectively followed. Minimal follow-up time was 2 years for subsidence and patient-reported outcome measures and 5 years for complications, reoperation, and revision. We compared subsidence, perioperative complications, reoperations, femoral component survival, Oxford Hip Score, EuroQol 5 Dimension, visual analog scale (VAS) for pain at rest, and VAS for pain during activity between stems. ResultsBoth groups were comparable regarding demographic, clinical, and surgery-related characteristics. We found more perioperative complications and stem revisions with the modular revision stem than with the primary conical stem. There were no statistical differences in subsidence, EuroQol 5 Dimension, Oxford Hip Score, and VAS for pain at rest or during activity between both stems. ConclusionIn revision total hip arthroplasty with Paprosky type II femoral defects, uncemented primary monobloc conical femoral stems showed the same clinical result as distal fixating modular stems with fewer complications and fewer stem revisions.

Determining the accuracy of preoperative total hip replacement 2D templating using the mediCAD\xae software

BackgroundTemplating is a preoperative planning procedure that improves the efficiency of the surgical process and reduces postoperative complications of total hip arthroplasty (THA) by improving the precision of prediction of prosthetic implant size. This study aimed to evaluate the accuracy of the preoperative cup and stem size digital 2D templating of THA with mediCAD® software and find the factors that influence the accuracy, such as indication for surgery, patients’ demographics, implant brand, and the assessors’ grade of education.MethodsWe retrospectively retrieved 420 patient template images of all patients who underwent THA between March 2018 and March 2021. Templating of all included images was processed using mediCAD® software a day before surgery by a newcomer physician to hip arthroplasty course (PGY-2 orthopedic resident or hip surgery fellow). Preoperative templating cup and stem sizes were compared with the actual inserted implant sizes.ResultAfter excluding ineligible patients, this study included 391 patients, 193 (49.4%) males and 198 (50.6%) females with a mean age of 43.3 ± 14.9. The average cup sizes predicted before and after surgery were 52.12 ± 14.28 and 52.21 ± 15.05 respectively, and the mean delta cup size (before and after surgery) was 2.79 ± 2.94. The delta stem size before and after surgery has a mean value of 1.53 ± 1.49. The acetabular cup components, measured within ± 0, ± 1, and ± 2 sizes, were 28.9%, 63.9%, 83.1% accurate, respectively. The femoral stem design component measured within ± 0, ± 1, and ± 2 sizes were 27.2%, 61.0%, 78.6% accurate, respectively. Wagner Cone® stem brand, DDH patients, and females showed significantly higher accuracy of stem size templating. Revision THA has the lowest accuracy in terms of cup size templating. The compression of accuracy rate between resident and fellow revealed no significant differences. Also, no significant difference was detected between the accuracy of templating performed in the first months with the second months of the arthroplasty course period.ConclusionOur study showed that under mentioned condition, templating using mediCAD® has acceptable accuracy in predicting the sizes of femoral and acetabular components in THA patients. Digital software like mediCAD® remains favorable because of the short learning curve, user-friendly features, and low-cost maintenance, leading to level-up patient care and THA efficacy. Further studies are necessary for clarifying the role of the assessor’s experience and expertise in THA preoperative templating.Level of evidenceLevel III (retrospective observational study).

Short-term results of total hip arthroplasty using a tapered cone stem for patients with previous femoral osteotomy

PurposeIn total hip arthroplasty (THA) for patients with previous femoral osteotomy, we hypothesized that a tapered cone stem may be an option due to the altered morphology of the proximal femur. The purpose of this study was to assess the short-term results of THA after femoral osteotomy using a tapered cone stem, and to identify issues that require further attention. MethodsTwenty-two hips in 21 consecutive patients who underwent THA after femoral osteotomy using a Wagner Cone tapered cone stem were retrospectively reviewed, with a mean follow-up period of 34.4 (range, 24–50) months. Clinical information was obtained from medical records. On preoperative radiographs, the Dorr type was classified based on the anteroposterior cortical index. On postoperative radiographs, the degree of stem subsidence and the stem location with the highest canal fill ratio were assessed. ResultsThe mean Harris hip score significantly improved from 55.2 at baseline to 84.8 at final follow-up. Radiologically, stem subsidence (>3 mm) was observed in seven hips, and it stabilized within 1 year after THA in all cases. In five of seven hips with stem subsidence, the highest postoperative canal fill ratio was observed in the distal third of the stem. The proportions of males and Dorr type A were significantly higher among hips with stem subsidence than among those without. During the follow-up period, no hips showed implant loosening or required revision surgery. ConclusionsThe occurrence of stem subsidence should be noted when using Wagner Cone stems for Dorr type A femurs after femoral osteotomy.

Midterm results of titanium conical Wagner stem with challenging femoral anatomy: Survivorship and unique bone remodeling

BackgroundComplex anatomy of the proximal femur makes total hip arthroplasty (THA) more challenging. Short, straight, fluted and conical titanium stem like the Wagner Cone can be helpful to address small femoral canal, increased femoral neck version, important leg length discrepancy or proximal femoral deformity. The outcome in these patients is less assured and associated with high rate of complications. Therefore, we did a retrospective study aiming to answer: 1) can the Wagner Cone stem provide acceptable mid- to long-term implant survivorship; 2) help minimizing perioperative adverse events; 3) produce favorable clinical outcome measured by WOMAC score; and 4) be associated with a favorable radiographic femoral bone remodeling at the last follow-up? HypothesisWagner Cone stem is an advantageous solution for the distorted proximal femur in complex THA. Patients and methodOur cohort was derived from the patient registries where medical records of 88 patients (103 hips) who underwent primary THA using the Wagner prosthesis were retrospectively reviewed. Then, data was analyzed for patients’ demographics and surgical data, and comparing preoperative, immediate postoperative and last follow-up data. Eleven patients (12 hips) were excluded (7 hips followed up less than 2 years or lost to follow-up, 3 hips that had the Wagner stem for revision and 2 Wagner stems inserted for periprosthetic fracture). This left 77 patients (91 hips) with Wagner cone stems implanted for more than 2 years between March 2003 and February 2017 by 7 surgeons in 3 academic hospitals. Implant revision, reoperations, WOMAC score and radiographic analyses were recorded at last follow-up. ResultsAfter a mean follow-up of 7.8 (range, 2.0–16.2) years, Wagner stem survivorship was 98.9% (95% CI: 94 to 100%) with one (1.1%) stem revision for failure of osteointegration. Five (5.5%) acetabular revisions, one for aseptic loosening, 2 for adverse reaction to metal debris and 2 for infection. One (1.1%) sciatic neuropathy and 4 (4.4%) intraoperative fractures were encountered. The mean WOMAC score was 90.5±11.4 (59–100). Radiographic analysis showed clear signs of stem osseointegration and hypertrophic bone remodeling in 82 cases (92.1%). ConclusionsUsed in complex cases with proximal distorted femurs, the Wagner Cone stem demonstrated a low complication rate, a high-rate consistent adaptive bone remodeling, excellent clinical results, and midterm survival. It is a safe, reliable and advantageous option in complex primary THA. However, the contribution of the underlying cause of the secondary osteoarthritis on the long-term survival of the stem remains to be demonstrated. Level of evidenceIV; retrospective study.

Risk factors of dislocation after total hip arthroplasty in patients with developmental dysplasia of the hip.

Dislocation following total hip arthroplasty (THA) is a well-known complication. However, there is little data on its rate and predictors in patients with developmental dysplasia of the hip (DDH). The current study is aimed to determine the rate and specific risk factors of dislocation following THA in DDH patients. All the medico-surgical records of primary THAs from January 2014 to January 2019 were retrospectively reviewed. They were categorized into three main groups: primary OA, DDH, and others. Pre-operative and post-operative radiographs, past medical and surgical history, and surgical notes were reviewed in DDH cases. In a total of 171 patients with DDH, 21 suffered from dislocation after THA (12%) which was significantly more frequent than those with primary OA. In univariate analysis, higher grade of dysplasia, smaller head size, intra-operative fracture, Wagner Cone stem, failure of offset restoration, and implanting the cup outside the Lewinnek's safe zone were identified as predictors of dislocation. In multiple regression analysis, however, only higher Crowe grade, intra-operative fracture, and post-operative acetabular offset less than 16mm were independent predictors of dislocation. Dysplastic hips can be more prone to post-THA dislocation than those with primary OA. Higher grades of dysplasia, failure of offset restoration, and intra-operative fracture can increase the rate of dislocation in this group of patients.

Total Hip Arthroplasty With the Wagner Cone Femoral Stem in Patients With Crowe IV Developmental Dysplasia of the Hip: ARetrospective Study.

The aim of this study is to assess treatment of Crowe type IV hip dysplasia with the Wagner cone femoral stem combined with transverse subtrochanteric shortening osteotomy and augmenting the osteotomy site using the intercalary segment as a strut autograft. One hundred twenty-seven hips of 91 patients diagnosed with Crowe type IV hip dysplasia and treated with total hip arthroplasty using the Wagner cone stem combined with transverse subtrochanteric shortening osteotomy were retrospectively evaluated by clinical and radiographic outcomes as well as complications. The mean follow-up was 8.4 years. The Harris Hip Score and the Western Ontario and McMaster University Osteoarthritis Index scores were significantly improved postoperatively (P= .000). Intraoperative femoral cracks were observed in 70 hips (55.1%) and all femurs healed smoothly. Femoral cracks did not have a significant effect on clinical outcomes, except for heterotopic ossifications (P= .032). The probability of 10-year survivorship of the components free of revision for any reasons as end point was 94.5%; when only the femoral components were considered the survivorship was of 96.9%. Transverse subtrochanteric shortening and augmenting the osteotomy site using the intercalary segment of bone resected from the shortened femur with the Wagner cone stem is an effective and reliable technique in the management of total hip arthroplasty in Crowe type IV hip dysplasia. Stable and firm placing of the femoral component which leads to an increased frequency of intraoperative femoral cracks does not have an unfavorable effect on clinical and radiological outcomes.

Long-term outcomes of cementless femoral stem revision with the Wagner cone prosthesis

BackgroundThe procedure of femoral stem revision is challenging, and bone conservation with less stress shielding is a mandatory effort in these cases. Although there are several reports of stem revision with stems designed for primary total hip arthroplasty (THA), there is no report on stem revision with the Wagner cone prosthesis.MethodsBetween 1996 and 2008, 41 hips of 41 consecutive patients were subjected to femoral revision THA using the Wagner cone prosthesis. The mean age during revision surgery was 56.1 years, and the mean follow-up period was 14.8 years. The clinical results were evaluated, and the femoral component was assessed radiologically.ResultsThe results showed that the average period from the first operation to revision THA was 8.0 years. Additionally, the mean Harris hip score improved from 52 points preoperatively to 83 points at the final follow-up. All stems showed bone integration in the radiological evaluation. A subsidence of more than 5 mm was observed in 3 out of 28 (10.7%) femoral stems. Two patients needed an acetabular revision for acetabular cup loosening during the follow-up period. Furthermore, one patient had recurrent dislocation and had to undergo revision surgery for soft tissue augmentation.ConclusionsWe achieved favorable clinical and radiological long-term outcomes in femoral stem revision using the Wagner cone prosthesis. This cementless femoral stem could be an option for femoral stem revision in cases with relatively good bone stock.

Cementless total hip arthroplasty for failed treatment of subtrochanteric fracture

BackgroundFailed treatment of subtrochanteric fractures commonly leads to pain, limping, and poor limb function. Cementless total hip arthroplasty (THA) could serve as an efficient salvage procedure in such cases. This study aimed to evaluate the outcomes and complications of salvage THA in failed subtrochanteric fracture fixation cases.MethodsFrom January 2001 to December 2017, cementless THA for failed treatment of subtrochanteric fractures was performed in 18 hips of 11 men and 7 women (average age, 74 years; age range, 57.0–89.0 years). Patients were followed up for clinical and radiological assessments in terms of implant survival and complications after a minimum follow-up of 2 years. The Wagner femoral stems (Zimmer, Warsaw, USA) were used in all 18 patients (100%), with the long-length stem (Wagner SL stem) and standard-length stem (Wagner cone stem) used in 11 and 7 patients, respectively.ResultsThe mean follow-up period was 5.2 years (range: 2.2–10.8 years). The mean Harris hip score (HHS) was 38.2 (range: 24–56) preoperatively and 85.4 (range: 79–92) at the last follow-up. The mean postoperative limb length discrepancy was 6.4 mm (range: 4–9 mm). Only one patient underwent revision due to bone in-growth failure of the femoral stem. One patient had an episode of postoperative dislocation and was treated with closed reduction without reoccurrence. Delayed union of the fracture site occurred in one patient. Patients who were previously treated with an intramedullary nail had a significantly shorter surgical duration, lesser intraoperative blood loss, and fewer blood transfusions than those who were previously treated with plate and screws. Kaplan–Meier survival rate with an endpoint of revision was 94.4% (95% confidence interval 72.7–99.9) at 5 years.ConclusionOur results indicate that cementless THA is a beneficial and effective procedure for salvaging the failed treatment of subtrochanteric fractures. The Wagner conical prosthesis has shown satisfactory function outcomes, stable fixation, and survival rate for these complex situations. However, attention should be paid to increased operation time, blood loss, and complications when performing THA for subtrochanteric fractures with failed fixation devices especially, plates and screws.

Total hip arthroplasty for dysplastic coxarthrosis using a cementless Wagner Cone stem

BackgroundTotal hip arthroplasty (THA) is currently the best surgical option for hip osteoarthritis secondary to developmental hip dysplasia (DDH); it may be extremely challenging, because of the hypoplasic proximal metaphysis, pathological anteversion, and excessive cervico-diaphyseal angle of the neck at the femoral side. The purpose of this retrospective study was to evaluate the long-term survival and clinical and radiological results of Conus uncemented stems, implanted in patients affected by hip osteoarthritis with Crowe not-type IV secondary to DDH.Material and methodsWe identified 100 consecutive THAs performed for DDH in 63 women and 24 men, with an average age of 53 years in a single center. Thirteen patients underwent bilateral hip replacement. The patients’ mean body mass index was 29.8 kg/m2 (range 27.1–35.6 kg/m2). The main indications for surgery were severe hip pain and considerable functional impairment: the preoperative Harris Hip Score was 29.5 on average (range 22–61). Radiologically, 8 hips were classified as Crowe I, 43 hips as Crowe II, and 49 hips as Crowe III. In all cases, we implanted the Wagner femoral cone prosthesis using the direct lateral approach; in the attempt to reestablish native hip biomechanics, 66 stems were 135° and 34 were 125°.ResultsThe mean follow-up of the study was 11.7 years (range 2.2–21.8 years). Harris Hip Score increased to a mean value of 71.5 points (range 52–93 points). Radiographic evaluation demonstrated osteointegration of the implant with stable bone growth observed at the stem–endosteum interface; signs of bone readaptation and thinning of the femoral calcar were present in nine hips. None of the patients underwent revision for septic or aseptic loosening of the stem; none sustained a periprosthetic fracture.ConclusionsThis study confirms the theoretical advantages that suggest the choice of the Wagner cone when technical difficulties during prosthetic surgery are expected owing to abnormal proximal femoral anatomy.Level of evidenceLevel IV, retrospective case study

Clinical Outcomes of Conical Hip Prosthesis Used In Primary Total Hip Arthroplasty

Introduction: Congenital dysplasia of the hip, presence of intramedullary bony pedestals, and related pathologies present unique challenges to the orthopaedic surgeon when considering total hip arthroplasty (THA). In these circumstances, a conical prosthesis has proven to be effective. The purpose of this study is to report the short-term radiological and clinical outcomes of the Wagner Cone Prosthesis® (Zimmer Biomet, Warsaw, Indiana) utilized for a range of etiologies at a major North American healthcare system. Materials and Methods: A retrospective study was performed at a single healthcare system between 2007 and 2018. Demographic variables, including age, sex, and laterality, as well as surgical variables, including femoral head size, neck-shaft angle, stem diameter, surgical approach, and indication for THA, were collected for each hip. Radiographs were also examined for subsidence, limb length discrepancy (LLD), and Crowe classification if the hip was dysplastic. Results: Thirty-one THAs were performed using a Wagner Cone Prosthesis®. No intraoperative or postoperative implant-related complications were reported. Fourteen hips were dysplastic, and of these, 10 were classified as Crowe I, one as Crowe II, two as Crowe III, and one as Crowe IV. No implant was observed to have subsidence greater than 1cm. The average LLD following arthroplasty was 1.38mm ± 9.4mm shorter than the contralateral side. Conclusion: The Wagner Cone Prosthesis® serves as a useful implant for THA. In our sample, it had excellent survivorship, impressive postoperative radiographic measurements obtained from most recent follow up, minimal mean subsidence, and minimal complication rates.

A controlled diaphyseal expansion osteotomy for the implantation of a wagner cone prosthesis in a stenotic femoral canal encountered in a polio limb: a case report of the technique

&lt;p class="Default"&gt;Dysplastic hips pose a significant technical challenge to arthroplasty surgeons. Such deformed hips might be encountered either in congenital and developmental conditions or as sequel of neuromuscular disorders (like poliomyelitis), following infections, or after childhood surgical procedures of the hip. The scientific literature, focussing on total hip arthroplasty (THA), for coxarthrosis in patients with residual poliomyelitis, is relatively rare. Several anatomical distortions seen in dysplastic femurs are described, one of which includes an undersized diaphysis with a stenotic medullary canal. We present a case of a 28 years old male with residual poliomyelitis who underwent a cementless THA for a non united transcervical neck of femur fracture. The patient had an extremely narrow medullary canal which posed a formidable difficulty in the procedure. This was overcome by a novel diaphyseal expansion osteotomy, which enabled the implantation of Wagner Cone prosthesis. This technique, which has hitherto not been described in the literature, can significantly facilitate the implantation of an appropriately sized stem in an undersized femur while at the same time ensuring a good long-term result.&lt;/p&gt;

Comparison of two different on-shelf femoral stems for Crowe type IV developmental dysplasia of the hip.

ObjectiveThis study was performed to evaluate the proximal anatomical compatibility of stems for treatment of Crowe IV developmental dysplasia of the hip (DDH) using a previously developed three-dimensional comparison technique.MethodsPatients with Crowe IV DDH who underwent computed tomography were retrospectively analyzed. The femoral medullary canals were three-dimensionally reconstructed, and models of cementless modular (S-ROM; DePuy Synthes) and conical (Wagner Cone; Zimmer Biomet) implants were used for virtual implantation. The negative point percentages (NPPs) were applied to verify fitting. The average distance (deviation) and the root mean square of the distance (RMSd) were used to quantify geometric compatibilities.ResultsFour (16.7%) and 12 (50.0%) femoral medullary canals could not be fitted properly with either the modular or conical implant. The NPPs in the distal comparison region were significantly greater in the conical than modular group. The deviation was significantly smaller in the modular than conical group. The RMSd was also significantly smaller in the modular than conical group.ConclusionsCompared with conical implants, modular implants might be more effectively used in patients with Crowe type IV DDH. However, some Crowe IV DDH femurs with severe deformity cannot be fitted with either of these two on-shelf implants.

Total Hip Arthroplasty With a Monoblock Conical Stem in Dysplastic Hips: A 20-Year Follow-Up Study

BackgroundTotal hip arthroplasty in patients with hip dysplasia is challenging as a result of complex anatomic deformities in the hip. The aim of the study was to evaluate the survivorship, the clinical and radiographic outcomes of cementless Wagner Cone stem in patients with dysplastic hip. MethodsThis retrospective study reports on 102 patients (135 hips) who have undergone total hip arthroplasty between 1993 and 1997. The mean age of patients was 51 years (range, 21-73). Minimum follow-up was 20 years. According to the Crowe classification, 38 hips presented dysplasia of grade I, 41 of grade II, 37 of grade III, and 19 of grade IV. ResultsKaplan-Meier survivorship for aseptic loosening was 97% (95% confidence interval, 94.4-99.6) at 20 years. The average Harris hip score increased from 43.4 points (range, 22-51) to 86.4 points (range, 39-100) (P < .0001) and average Merle d’Aubignè score increased from 8.4 (range, 4-13) to 15 (range, 5-18) (P < .0001); at the last follow-up, average University of California at Los Angeles activity score and visual analog score were 4.53 (range, 1-9) and 1.25 (range, 0-6), respectively; 17% of heterotopic ossification and 19.2% of radiolucency lines around the stem were reported. ConclusionMonoblock Wagner Cone stem is a reliable option in dysplastic hip with an excellent survivorship and good clinical and radiographic outcome in the long term.