Prothèses totales de hanche après échec de fixation de fractures per et sous-trochantériennes chez les sujets âgés

Outcomes of total hip arthroplasty using dual mobility cups following failed internal fixation of proximal femoral fractures at a mean follow-up of 6 years

INTRODUCTION

Performing total hip arthroplasty (THA) after failed internal fixation of proximal femoral fractures (PFF) is known to be associated with high rates of complications. Dual mobility cups (DMC) are known to lower dislocation events in high-risk patients. Very few reports investigated the outcomes of THA using DMC following failure of internal fixation for PFF.

METHODS

This is a retrospective monocentric continuous study of 31 patients who underwent THA with DMC after failed internal fixation of PFF. The clinical assessment was based on the modified Harris hip score (mHHS) at the last follow-up. The complication rates and radiological analyses were recorded.

RESULTS

The mean follow-up period was 5.96 ± 4.2 years. At the last follow-up, the mean mHHS was 92.9 ± 9.1 with 71% of the patients describing their operated hip as a forgotten hip. No dislocation or aseptic loosening events were noted. One patient developed a septic loosening of the implant. No significant radiological changes were recorded. Sixteen stems (51.6%) were placed in a neutral position, 13 (42%) in valgus (2.74 ± 1.72°), and 2 (6.4%) in varus (6.94 ± 2.02°).

CONCLUSION

This study emphasizes the advantage of using DMC following failed internal fixation of PFF in reducing dislocation and complication events in this high-risk population.

No effect of hydroxyapatite-coated sliding hip screw threads on screw migration in the femoral head/neck of pertrochanteric fractures: a randomized controlled trial using radiostereometric analysis

INTRODUCTION

Cut-out is the most frequently reported mechanical failure of internal fixation of pertrochanteric fractures. The purpose of this study was to examine if hydroxyapatite-coated screw thread on a sliding hip screw (SHS) could reduce screw migration within the femoral head in patients with stable pertrochanteric fractures.

MATERIALS AND METHODS

In a double-blinded randomized controlled study, 37 patients at mean age 78 (range 56-96), with pertrochanteric fracture (Evans I, II, IV) received surgery with a SHS with a hydroxyapatite-coated or a non-coated lag screw thread. Radiostereometry and standard radiographs were obtained 1 day, 6 weeks, 3- and 6 months post-operatively to evaluate screw and fracture migration and fracture reposition. The two groups were combined to describe fracture migration.

RESULTS

There was similar and small screw migration in the femoral head between the two groups at 6 weeks, 3- and 6 months (p > 0.12). Fracture migration occurred predominantly in the first 6 weeks, where fracture impaction was 5.95 mm (CI 95% 2.87 to 9.04) and anterior rotation of the femoral head was -2.94° (CI 95% - 5.22 to - 0.66). Migration of the fracture (total translation) correlated to the post-operative fracture reposition (p = 0.002), but not significantly to screw migration (p = 0.09). Neither screw total translation (rho 0.06, p = 0.79) nor fracture total translation (rho 0.04, p = 0.77) correlated with bone mineral density.

CONCLUSION

There was no clinical benefit of hydroxyapatite coating on lag screw migration in this patient cohort. Migration of the pertrochanteric fractures was higher with poor fracture reposition but fractures generally stabilized after 6 weeks follow-up. The study was registered at ClinicalTrials.gov (NCT05677061).

LEVEL OF EVIDENCE II

Patient-blinded prospective randomized study. Trial registration number The study was registered at ClinicalTrials.gov (NCT05677061).

Outcome of proximal femur replacement in failed internal fixation of hip fractures, a case series

Introduction

Failure of hip implant surgeries can be caused by various factors. Failure of internal fixation results in pain and restricted ambulation. In management of an elderly patient with hip fractures, the aim is to ambulate patient. The purpose of our study is to assess the outcomes of proximal femur replacement in the management of failed hip surgeries for fractures of the proximal femur.

Materials and methods

A retrospective analysis of 26 patients, who underwent proximal femur replacement for failed surgeries of hip fracture during the period from April 2011 to March 2018, was conducted. All patients who underwent proximal femur replacement for failed hip implants were enrolled into the study.

Results

Total patients were 26. The mean follow was (12–91 months). The mean Harris Hip score improved from 26 preoperative to 66.7(45–91). Three patients developed dislocations which were managed with closed reduction. Three patients died within one year of surgery, one patent died of sepsis from implant infection at four months after surgery, one patient died of Myocardial infarction. Three patients developed surgical site infection of which one has superficial surgical site infection which was managed with oral antibiotics, in other case developed deep surgical site infection and was managed with wound debridement and IV antibiotics for 6 weeks, in third wound debridement was done but patient died of sepsis.

Conclusion

Proximal femur replacement with modular stem implant has advantages over conventional hip implant in patients undergoing surgery after failure of internal fixation.

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Failure of hip implant surgeries can be caused by various factors.

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In management of an elderly patient with hip fractures, the aim is to ambulate patient.

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Proximal femur replacement with modular stem implant has advantages over conventional hip implant.

Effects of implant-delivered insulin on bone formation in osteoporotic rats

Osteoporosis is a major cause of age-related fractures. Healing complications in osteoporotic patients are often associated with increased mortality and morbidity. Stimulation of the implant-adjacent bone could be beneficial in terms of the surgical outcome. Over the past decade, numerous investigations have implicated insulin in normal bone growth, and recent studies have described the advantages of administering insulin locally to increase bone formation. Therefore, we hypothesized that insulin-coated titanium implants would increase bone formation in osteoporotic animals. The aim of this study was to evaluate the effects of insulin delivered from an implant surface on bone-related gene expression and bone formation in osteoporotic rats. Characterizations of the surfaces of insulin-coated and control implants were performed using ellipsometry and interferometry. Forty ovariectomized and four healthy Sprague Dawley rats were used and implants were inserted in the tibias. The systemic effect of insulin was assessed by measuring the blood glucose levels and total body weight. The animals were sacrificed either 1 day or 3 weeks postimplantation. Implant-adherent cells were analyzed by quantitative real-time PCR, and the bone adjacent to the implants was examined by microcomputed tomography and histomorphometry. The insulin-coated implants had no systemic effects. The insulin-coated samples demonstrated significantly lower expression of the gene for interleukin 1β (p = 0.019) at 1 day, and significantly exhibited more periosteal callus (p = 0.029) at 3 weeks. Locally delivered insulin has potential for promoting bone formation and it exerts potentially anti-inflammatory effects in osteoporotic rats. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A:2472-2480, 2018.

Is a short stem suitable for patients with hip dysplasia? A report on technical problems encountered during femoral reconstruction

INTRODUCTION

A wide variety of stems have been used for the treatment of osteoarthritis secondary to advanced hip dysplasia. Since evidence for using short stems in dysplastic hips is limited, we planned to analyse the technical problems encountered when reconstructing the proximal femur of patients with osteoarthritis secondary to congenital dysplasia of the hip treated with total hip arthroplasty (THA) using a type 2B short stem.

METHODS

We prospectively analysed 17 patients (22 hips) treated with primary THA performed with a single-branded short uncemented stem with metaphyseal fixation (MiniHip™; Corin). We excluded cases in which other type of stems were used, or in which retrospective data was only available. Mean follow-up was 41.22 months (minimum 24). We analysed clinical outcome using the modified Harris Hip Score (mHHS) and pain using the visual analogue scale (VAS). Radiographs were examined in order to determine causes of complications and revision surgery.

RESULTS

All patients showed statistically significant improvement when preoperative and postoperative values for mHHS (54.19 vs. 94.57; p = 0.0001) and for pain VAS (8.71 vs. 0.71; p = 0.0003) were compared. No cases of thigh pain, instability or infection were found. 1 case of acetabular cup loosening and 1 case of periprosthetic fracture were diagnosed at 8 months and 45 days, respectively. Overall survival was 84.7% at 5 years (CI 95%, 64.4-105.3) with revision for any reason as an end point. When stem performance was separately evaluated, it showed a survival rate of 100% at 5 years with revision for aseptic loosening as an end point.

CONCLUSIONS

THA with a type 2B short stem for the treatment of dysplastic osteoarthritis showed very few technical intraoperative problems, being a useful alternative for femoral reconstruction.

Fatigue failure of the cephalomedullary nail: revision options, outcomes and review of the literature

Cephalomedullary nail (CMN) failure is a rare entity following hip fracture treatment. However, it poses significant challenges for revision surgery, both mechanically and biologically. Nail failure rates have been reported at < 2%; however, no published studies have reported revision surgery procedures and their respective outcomes. We present a regional experience, with outcomes, of the revision options. We identified 20 fatigued CMNs that underwent four different revision procedures. Mean age was 73 ± 15.24 years, with a 3:1 female preponderance, and a median ASA grade of 3. Post-operative CMN radiographs demonstrated a significant number of fractures were fixed in varus, with reductions in neck-shaft angles post-operatively. A "poor" quality of reduction resulted in significantly earlier nail failure, compared to "adequate" and "good" (p = 0.027). Tip-Apex Distance (TAD) mean was 23.2 ± 8.3 mm, and an adequate TAD with three-point fixation was seen in only 35% of cases. Mean time to failure was 401.0 ± 237.2 days, with mean age at failure of 74.0 ± 14.8 years. Options after failure included revision CMN nail, proximal femoral locking plate (PFLP), long-stem or restoration arthroplasty, or femoral endoprosthesis. Barthel Functional Index scores showed no significant difference at 3 and 12 months post-operatively, nor any difference between treatment groups. Mean 12-month mortality was 30%, akin to a primary hip fracture mortality risk according to NICE guidelines. Mortality rates were lowest in revision nails. Subsequent revision rates were higher in the PFLP group. There is no reported evidence on the best surgical technique for managing the failed CMN, with no clear functional benefit in the options above. Good surgical technique at the time of primary CMN surgery is critical in minimising fatigue failure. After revision, overall mortality rates were equivalent to reported primary hip fracture mortality rates. Further multicentre evaluations are required to assess which technique convey the best functional outcomes without compromising 12-month mortality rates.

[Total hip arthroplasty for the treatment of congenital hip dislocations in adults: about 15 cases]

Total hip arthroplasty for the treatment of congenital dislocation represents a challenge for the orthopedic surgeon. It is now well established that the treatment of congenital hip dislocation in adults is a real "functional miracle". The evolution of surgical techniques and materials has expanded the indications for prosthetic replacement including the most complex cases and thus going against Charnley and Feagin who wrote in 1973 that there was no place for total hip arthroplasty in inveterate dislocations. We conducted a retrospective study of a series of THP 15 for the treatment of congenital hip dislocation in adults;sociodemographic, clinical, paraclinical and therapeutic data were collected from the medical records of 15 patients and also via a written questionnaire which was completed during their last follow-up visit. The average age of our patients was 28 years; female sex ratio was 2F/1H. Severe dysplasia stage VI according to Crowe's classification was present in 4 cases, type III in 9 cases and type II only in 2 cases. All patients underwent cemented total hip arthroplasty, a reinforcement ring was used in 9 cases and a bone graft in 2 cases. At last follow-up visit PMA functional scores were excellent and very good in 74% of cases. Surgical treatment of congenital hip dislocations in adults must meet strict health standards as congenital hip dislocations often occurs in young female population that is more demanding as to the aesthetic and functional outcomes. Several surgical techniques have tried to solve the problems related to this disease, acetabular and femoral hypoplasia, leg length inequality. Total hip arthroplasty for the treatment of congenital dislocations in adults remains a challenge for the orthopaedic surgeon. This is a difficult surgical procedure which requires technical skills and careful pre-design programming to reduce the occurrence of adverse events especially in the particular case of young female population.

Three-dimensional bone-implant movements in trochanteric hip fractures: Precision and accuracy of radiostereometric analysis in a phantom model

The accuracy and precision of RSA were evaluated in the experimental study of screw cut-out complication after fixation of trochanteric fractures. A plastic bone model of a two-part trochanteric fracture was constructed with a Gamma nail implant incorporating RSA markers. The femoral head fragment was attached to a separate rotational table and the femoral shaft was mounted on the micrometer. Three main motions were simulated: Femoral head translation and rotation along the axis of the lag screw and fracture fragment translation along anatomical axes. Accuracy and precision were determined according to ISO 16,087 and ASTM standard F2385-04. Translations along the lag screw axis were measured with a precision within  ±0.14 mm and an accuracy within ±0.03 mm. With simultaneous translations along all three anatomical axes, lowest precision was measured for the x-axis (±0.29, 0.07 mm, respectively), but improved when analyzed as a vector (±0.08, 0.03 mm). The precision and accuracy of femoral head rotations were within 0.5° and 0.18°, respectively. The resolution of the RSA method tested in this model was high, though it varied depending on the type of analyzed motion. This information is valuable when selecting and interpreting outcome parameters evaluating implant migration and osteosynthesis stability in future clinical RSA studies.

Total hip arthroplasty after previous fracture surgery

Total hip arthroplasty can be a very effective salvage treatment for both failed fracture surgery and hip arthritis that may occur after prior fracture surgery. The rate of complications is significantly increased including especially infection, dislocation, and loosening. Complications are more likely to occur after failed open reduction and internal fixation than after posttraumatic arthritis. Adequately ruling out infection before hip arthroplasty can be difficult. The best predictor of infection is a prior infection. Long-term outcomes can be comparable to outcomes in other conditions if complications are avoided.

Salvage hip arthroplasty after failed fixation of proximal femur fractures

We reviewed 46 patients who underwent salvage hip arthroplasty (SHA) for revision of failed cannulated screws (CS), sliding hip screws (SHS), or intramedullary nails (IMN). The primary objective was to determine differences in operative difficulty. SHA after failed femoral neck fixation was associated with lower intra-operative demands than after failed peri-trochanteric fractures. Similarly, analysis by the index implant found that conversion arthroplasty after failed CSs was associated with lower intra-operative morbidity than failed SHSs or IMNs; differences between SHS and IMN were not as clear. Importantly, intra-operative data in cases of failed SHSs were similar regardless of the original fracture type, showing the device played a larger role than the fracture pattern. Complications and revision surgery rates were similar regardless of fracture type or fixation device. Our results suggest that operative demands and subsequent patient morbidity are more dependent on the index device than the fracture pattern during SHA.

Complex primary total hip arthroplasty

Although total hip arthroplasty is now a classic procedure that is well controlled by orthopedic surgeons, some cases remain complex. Difficulties may be due to co-morbidities: obesity, skin problems, muscular problems, a history of neurological disease or associated morphological bone deformities. Obese patients must be informed of their specific risks and a surgical approach must be used that obtains maximum exposure. Healing of incisions is not a particular problem, but adhesions must be assessed. Neurological diseases may require tenotomy and the use of implants that limit instability. Specific techniques or implants are necessary to respect hip biomechanics (offset, neck-shaft angle) in case of a large lever arm or coxa vara. In case of arthrodesis, before THA can be performed, the risk of infection must be specifically evaluated if the etiology is infection, and the strength of the gluteal muscles must be determined. Congenital hip dysplasia presents three problems: the position and coverage of the cup, placement of a specific or custom made femoral stem, with an osteotomy if necessary, and finally lowering the femoral head into the cup by freeing the soft tissues or a shortening osteotomy. Acetabular dysplasia should not be underestimated in the presence of significant bone defect (BD), and reconstruction with a bone graft can be proposed. Sequelae from acetabular fractures presents a problem of associated BD. Internal fixation hardware is rarely an obstacle but the surgical approach should take this into account. Treatment of acetabular protrusio should restore a normal center of rotation, and prevent recurrent progressive protrusion. The use of bone grafts and reinforcement rings are indispensible. Femoral deformities may be congenital or secondary to trauma or osteotomy. They must be evaluated to restore hip biomechanics that are as close to normal as possible. Fixation of implants should restore anteversion, length and the lever arm. Most problems that can make THA a difficult procedure may be anticipated with proper understanding of the case and thorough preoperative planning.