Long-Term Results of Revision Total Hip Arthroplasty Using a Modern Extensively Porous-Coated Femoral Stem

Use of Limited Femorotomy as an Alternative to Extensive Trochanteric Osteotomy for Cementless Femoral Prosthesis Revision

Background

Cementless stem extraction during hip arthroplasty revision can be challenging and sometimes requires a femoral opening to be performed with limited posterior femorotomy techniques been described. The study objective was to assess the efficacy of these techniques and the perioperative and postoperative complication rates.

Methods

This study included 224 patients who underwent cementless stem revision. Stem extraction followed the same sequence: an initial endomedullary extraction attempt, followed by suspended posterior unicortical vertical diaphyseal femoral osteotomy. Metaphyseal extension of the osteotomy and lateral-distal cortical extension at the stem tip were performed if the procedure failed, followed by extended trochanteric osteotomy (ETO). The incidence rates of perioperative fracture, reimplanted stem type (standard or revision), postoperative subsidence, and fracture were analyzed.

Results

Femoral opening was required in 15.6% of patients; 75% underwent limited femorotomy (28 patients, 75% suspended, and 25% extended), and 25% (7 patients) underwent ETO. Endomedullary extraction was performed in 84.4% (189) of the patients. The perioperative fracture rates were 16.9%, 0%, and 14.3% in the endomedullary, limited femorotomy, and ETO groups, respectively (P = .032). The standard stem utilization rates were 94.9%, 82.1%, 58.6%, and 28.6% (P < .001) for the endomedullary, limited femorotomy, perioperative fracture, and ETO groups, respectively. Postoperatively, the subsidence rates were 7.5%, 0%, and 28.6% (P = .042), and the fracture rates were 4.3%, 3.6%, and 0% (P > .999) in the endomedullary, limited osteotomy, and ETO groups, respectively.

Conclusions

Limited femorotomy techniques are reliable methods for extracting cementless stems, when necessary, with a reduced risk of fracture. Postoperatively, these patients appear to have comparable stem subsidence and a low risk of fracture.

The 3D-Printed Customized Femoral Short Stem Offers Improved Anatomical Parameters Restoration, Fitness and Biomechanical Performance Compared With Traditional Femoral Stem

OBJECTIVE

The traditional femoral stem is unsuitable for patients with severe proximal femoral bone defects or deformities. However, 3D-printed customized designs offer improved proximal femoral canal contact and enhance the initial stability of the femoral prosthesis. Therefore, this study aims to compare the anatomical parameters, contact parameters, and performance of the 3D-printed customized femoral short (CFS) stem with those of the traditional femoral stem following total hip arthroplasty (THA).

METHODS

An in vitro study simulating THA was performed using artificial femur models, with a 3D-printed CFS stem as the experimental group and a Trilock stem as the control group. Anatomical parameters, fitness, filling, micro-motion, and strain distribution were evaluated using artificial femoral models. Micro-motion and strain were recorded under different simulated bodyweight loading using a 3D digital image correlation measurement system.

RESULTS

The neck-shaft angles (NSA) and coronal femoral horizontal offset (CFHO) of the 3D-printed CFS stem (NSA: 125.22°, CFHO: 41.03 mm) were closer to those of the intact femur (NSA: 127.37°, CFHO: 43.27 mm) compare with the Trilock stem (NSA: 132.61°, CFHO: 32.98 mm). In addition, the 3D-printed CFS stem showed improved fitness at cross-sections (The top of the lesser trochanter: 6.31%, the middle of the lesser trochanter: 23.42%, the bottom of the lesser trochanter: 26.61%) and reduced micro-motion under different simulated bodyweight loads (1000: 0.043, 1375: 0.056, 2060 N: 0.061 mm).

CONCLUSIONS

The 3D-printed CFS stem provides improved restoration of anatomical parameters, enhanced fitness, and superior biomechanical performance compared with the Trilock stem.

Long-term results of revision total hip arthroplasties using cementless stems and allografts for paprosky type IIIB and IV femoral defects short title: Revision hip arthroplasty in type IIIB and IV femoral defects

PURPOSE

We determined long-term (1) clinical results of revision total hip arthroplasty (THA) in the presence of Paprosky type IIIB and IV femoral defects using validated scoring instrument; (2) osseointegration and bone remodeling; (3) the fate of cortical strut onlay allograft; (4) rates of revision and osteolysis; and (5) survivorship of the cementless stem.

METHODS

We reviewed the results of 240 revision THAs in 220 patients (mean age, 59 years, range, 36-67 years) performed with an extensively porous-coated femoral stem (Solution stem; DePuy, Warsaw, Indiana) combined with a cortical strut onlay allografts for Paprosky Type IIIB and IV femoral diaphyseal bone defects from February 1994 to June 2003. Demographic data, Harris hip score, WOMAC score, UCLA activity score, and radiographic data were recorded. We determined the fate of strut cortical strut allograft and component survival rates at a mean of 26.5 years using revision and aseptic loosening as end points. Minimum follow-up was 21 years (range, 21-30 years).

RESULTS

The clinical results improved significantly for the Harris hip score, WOMAC, and UCLA activity scores (p < 0.001). At the final follow-up, mean Harris hip, WOMAC, and UCLA activity scores were 83 ± 15 (34-100), 20 ± 15 (11-52) and 6.7 ± 1.3 (5-8) points, respectively. Of the 240 femoral stems, 218 (91%) had bone ingrowth, and 22 (9%) were unstable. Allografts were well incorporated in the host femur in all hips. The resorption of allografts was graded as mild in 192 hips (80%) and moderate in 48 hips (20%). A Kaplan-Meier survivorship analysis at a mean of 26.5 years follow-up showed that the survival rate of the femoral component was 91% (95% CI, 0.88-0.96) with re-revision for any reason as the endpoint for failure. The survival rate at a mean of 26.5 years for worst case scenario was 76% (95% CI, 0.71-0.88).

CONCLUSION

We found good results at a mean of 26.5 years after the revision surgery in terms of longevity and functional outcome using an extensively porous-coated stem combined with cortical strut allografts in the Paprosky Type IIIB and IV femoral diaphyseal defects. We agree that the initial quality of an uncomplicated revision of THA using supportive cortical strut allografts maintains relatively well beyond minimum 21 years of follow-up. Future studies might compare this approach with allograft-prosthesis composites, proximal femoral replacement, or modular fluted tapered stems.

Shape-memory sawtooth-arm embracing clamp used in complex femoral revision hip arthroplasty for stem stability: average 9-year follow-up study

BACKGROUND

Nickel-Titanium shape-memory sawtooth-arm embracing clamps (SSECs) have been used in revision total hip arthroplasties (rTHAs) to protect stem stability. This study was to introduce this technique and report its mid to long-term clinical and radiographic outcomes.

METHODS

We retrospectively reviewed all patients implanted with SSECs in our department from January 2008 to December 2015. 41 patients (41 hips) were finally included. Radiographs and Harris hip scores (HHS) were collected. Radiographs were blindly analyzed for evidence of loosening, subsidence and stress shielding. HHS were compared to previous records by student's t tests. The average follow-up period was 9.3 years.

RESULTS

All stems were stably fixed with no signs of loosening. The mean stem subsidence was 0.9 mm (range, 0 to 3 mm). Only one patient (2.4%) demonstrated the fourth degree of stress shielding, with the others none or minor bone resorption. The mean HHS at the final follow-up was 84.2 (range, 81 to 91), which was improved from 17.4 (range, 0 to 37) before surgery. No implant failures or re-revisions occurred. Dislocation occurred in 1 case during the follow-up period.

CONCLUSIONS

The SSEC protected stem fixation and achieved favorable clinical and radiographic outcomes in this 9-year follow-up study. It offered an additional extramedullary fixation option for surgeons to choose from in treating complex femoral revision arthroplasties.

Cemented versus uncemented stems for revision total hip replacement: A systematic review and meta-analysis

BACKGROUND

The popularity of uncemented stems in revision total hip arthroplasty (THA) has increased in the last decade.

AIM

To assess the outcomes of both cemented and uncemented stems after mid-term follow up.

METHODS

This study was performed following both the Preferred Reporting Items for Systematic Reviews and Meta-analyses Statement and the Cochrane Handbook for systematic reviews and meta-analysis guidelines. Articles were chosen irrespective of country of origin or language utilized for the article full texts. This paper included studies that reviewed revision THA for both cemented or uncemented long stems.

RESULTS

Three eligible studies were included in the meta-analysis. Analysis was conducted by using Review Manager version 5.3. We computed the risk ratio as a measure of the treatment effect, taking into account heterogeneity. We used random-effect models. There were no significant differences found for intraoperative periprosthetic fractures [risk ratio (RR) = 1.25; 95% confidence interval (CI): 0.29-5.32; P = 0.76], aseptic loosening (RR = 2.15, 95%CI: 0.81-5.70; P = 0.13), dislocation rate (RR = 0.50; 95%CI: 0.10-2.47; P = 0.39), or infection rate (RR = 0.99, 95%CI: 0.82-1.19; P = 0.89), between the uncemented and the cemented long stems for revision THA after mid-term follow-up.

CONCLUSION

This study has evaluated the mid-term outcomes of both cemented and uncemented stems at first-time revision THA. In summary, there were no significant differences in the dislocation rate, aseptic loosening, intraoperative periprosthetic fracture and infection rate between the two cohorts.

Revision Hip Arthroplasty Using a Modular, Cementless Femoral Stem: Long-Term Follow-Up

BACKGROUND

As the number of primary total hip arthroplasty (THA) cases increase, so does the demand for revision operations. However, long-term follow-up data for revision THA is lacking.

METHODS

A retrospective review was completed of patients who underwent revision THA at a single institution between January 2002 and October 2007 using a cementless modular stem. Patient demographic, clinical, and radiographic data was collected. Preoperative and postoperative patient-reported outcome scores were compared at a minimum of fourteen-year follow-up.

RESULTS

Eighty-four patients (89 hips) with a median age of 69 years (range, 28 to 88) at operation were included. Indications for revision included aseptic loosening (84.2%), infection (12.4%), and periprosthetic fracture (3.4%). Twenty-two hips sustained at least 1 complication: intraoperative fracture (7.9%), dislocation (6.7%), prosthetic joint infection (4.5%), deep venous thrombosis (3.4%), and late periprosthetic fracture (2.2%). There were no modular junction complications. Eight patients underwent reoperations; only three involved the stem. Thirty-eight patients (45%) were deceased prior to final follow-up without known reoperations. Twenty-seven patients (32%) were lost to follow-up. Twenty-one patients (23%) were alive at minimum fourteen-year follow-up. Complete patient-reported outcomes were available for nineteen patients (range, 14 to 18.5 years of follow-up). Significant improvement was seen in UCLA activity, VR-12 physical, hip disability and osteoarthritis outcome score , joint replacement., and Harris Hip score pain and function scores.

CONCLUSION

Challenges of long-term follow-up include patient migration, an unwillingness to travel for re-examination, medical comorbidities, advanced age, and death. The cementless modular revision stem demonstrated long-term clinical success and remains a safe and reliable option for complex revision operations.

Novel Design of the Compound Sleeve and Stem Prosthesis for Treatment of Proximal Femur Bone Defects Based on Topology Optimization

The loosening of traditional prosthetics is among the leading causes of surgical failure of proximal femoral bone defects. A novel compound sleeve and stem prosthesis was designed using an optimization methodology that combined an octet-truss porous structure with density-based topology optimization to improve stability, promote bone ingrowth, and enhance biomechanical properties. Biomechanical changes were assessed using finite element analysis. The distribution of stress, the strain energy density, and the relative micromotion in the optimized group were considered. The optimized sleeve prosthesis achieved a 31.5% weight reduction. The maximum stresses in the optimized group were observed to decrease by 30.33 and 4.74% at the back sleeve and neck part of stem prosthesis, with a 29.52% increase in the femur, respectively. The average stress in most selected regions in the optimized group was significantly greater than that in the original group (p &lt; 0.05). The maximum relative micromotion decreased by 15.18% (from 63.9 to 54.2 μm) in the optimized group. The novel designed compound sleeve and stem prosthesis could effectively improve the biomechanical performance of next-generation prosthetics and provide a microenvironment for bone ingrowth. The presented method could serve as a model for clinical practice and a platform for future orthopedic surgery applications.

Revision Total Hip Arthroplasty with Primary Stem or Full-Porous-Coated Long Stem for Aseptic Femoral Component Loosening: A Matched-Pair Study

Background

Revision total hip arthroplasty (RTHA) for loosening the femoral stem is a technical challenge. Distally fixed, full-porous-coated long stems are widely accepted as the standard selection for these revisions. However, the success of primary stems in RTHA is not well known.

Methods

This study enrolled 24 patients with aseptic loosening of the femoral stem who underwent RTHA using primary stems. Another 72 patients with aseptic loosening who underwent RTHA using full-porous-coated long stems were matched in terms of operation date, proximal femoral bone stock (Paprosky classification), sex, and age. The primary and secondary outcomes of failure were the need for revision for any reason and the radiographic change in the stem respectively.

Results

In the primary stem group, one patient had a periprosthetic fracture and received a second RTHA 2 years after the previous one. The primary outcome’s 5-and 10-year survival rates were both 95.8%. For the matched comparison group, one patient had an immediate periprosthetic fracture of the femoral shaft requiring further open reduction internal fixation surgery. Another patient had a full-porous-coated long stem breakage 6 years postoperatively, which required a second RTHA. The primary outcome’s 5-and 10-year survival rates were 98.6% and 97.2%, respectively.

Conclusion

Primary stems can achieve non-inferior clinical success compared to a full-porous-coated long stem for aseptic stem loosening RTHA in patients with adequate proximal femoral bone stock.

A Comparison of Risks and Benefits Regarding Hip Arthroplasty Fixation

Since the field-changing invention of noncemented hip arthroplasty fixation in the 1980s, noncemented fixation has been progressively replacing cemented fixation. However, analyses of fixation frequencies reveal new patterns in cement versus noncemented preferences. Although cementation is again gaining ground in the United States, noncemented models remain the dominant fixation mode, seen in more than 90% of all hip arthroplasties. This stark preference is likely driven by concerns regarding implant durability and patient safety. Although advances in surgical techniques, intensive perioperative care, and improved instrument have evolved in both methods, data from large arthroplasty registries reveal shifting risks in contemporary hip arthroplasty, calling the use of noncemented fixation into question. Varying risk profiles regarding sex, age, or health comorbidities and morphological and functional differences necessitate personalized risk assessments. Furthermore, certain patient populations, based on the literature and data from large registries, have superior outcomes from cemented hip arthroplasty techniques. Therefore, we wanted to critically evaluate the method of arthroplasty fixation in primary hip arthroplasties for unique patient populations.

Minimum ten-year results in revision total hip arthroplasty using titanium fully porous long stem

PURPOSE

The fully porous long stem could be used for diaphyseal locking and achieve bypass fixation in revision total hip arthroplasty (THA). This study evaluated long-term results for fully porous long stems made of titanium alloy in revision THA.

METHODS

Between 2003 and 2010, 45 consecutive femoral revisions were performed using fully porous long stems. Thirty-eight hips had complete clinical and radiographic data for a mean of 13.8 years (range, 10-16.7 years). Femoral bone loss was Paprosky type II in 14 hips, type IIIA in 18 hips, and type IIIB in six hips. Clinical results were analyzed using the Merle d'Aubigné and Postel scoring system. Femoral stress shielding was graded. Radiological loosening of the femoral component was evaluated. Kaplan-Meier survival analysis was performed with revision for any reason as the end-point.

RESULTS

Mean Merle d'Aubigné and Postel score improved significantly from 10.7 before revision to 14.5 at latest follow-up (p < 0.001). Third-degree stress shielding was found in seven hips, and fourth degree in 11 hips. Radiological femoral loosening occurred in one hip, which was revised. Another hip was revised for stem fracture. Kaplan-Meier cumulative survival rate was 94.7% at both ten and 15 years.

CONCLUSION

Although stress shielding is a concern with fully porous stems, this stem was useful in revision THA and provided satisfactory long-term results in hips with Paprosky types II, IIIA, and IIIB.

Survival and outcome of total elbow arthroplasty for distal humeral fracture at long term follow-up

Background Total elbow arthroplasty is an accepted procedure for the treatment of acute comminuted distal humeral fractures in elderly. Few long-term outcomes are available. The purpose of this study was to examine long-term clinical and radiological outcomes of prosthesis performed (January 2002-June 2015) for complex intra- fractures of the distal humerus (AO/C) in patients older than 65 years with low functional demands. Materials and Methods Further inclusion criteria were: the availability of a clinical and radiological follow-up of minimum 5 years and pattern of closed fracture. Demographic data and characteristics of patients were collected. All patients were clinically and radiographically assessed after 2 and 5 years from surgery. Results Twelve patients were included with complete available data. The mean follow-up was 7.6 years. Five patients reported a worsening of the elbow functionality through the follow-ups. Five subjects had complications. There were no cases of revision surgery. The quality of fixation showed a progressive worsening with increase of radiolucency both on humeral and ulnar side. The recorded MEPS showed no correlation with the grade of periprosthetic osteolysis. Polyethylene bushing wear was scored of grade 2 in one subject who had showed type 4 Morrey radiolucency. Discussion and Conclusions Total elbow arthroplasty is an effective and reliable procedure for comminuted fractures of the distal humerus in elderly, although the incidence of complications can not be considered as negligible. For the majority of these patients, a well-performed implant will give them a well-functioning elbow for their remaining life.