Introduction: Revision hip arthroplasty for aseptic loosening of femoral component is successfully treated with impaction bone grafting technique. Owing to easier technique and shorter operative time, distally fixed non-cemented long stems have gained popularity in the present era. However, use of long stems could make subsequent re-revision difficult due to further bone loss. The standard length stem has been often critiqued due to apprehension of peri-prosthetic fracture.

This study aims to determine the long-term outcomes of the impaction bone grafting of the femur for aseptic loosening in revision hip arthroplasty using standard length C-stems. 168 total hip revisions of 162 patients with impaction bone grafting and cemented standard C-stem (done with standardized technique) between 1995 and 2008 at a tertiary referral centre were included. Revisions for infection and segmental bone defects were excluded.

Mean follow-up of the 168 revision hips was 10.5 years (range 5 – 19.1 years). 14 patients (8.3%) were re-revised, reasons being, persistent deep infection (1.8%), repeated dislocations (1.2%), cup loosening (4.8%) and stem loosening (1.2%). Only 1 patient (0.6%) was re-revised due to stem loosening alone. No peri-prosthetic fractures (intra-operative or post-operative) or stem breakage were identified.

Use of standard stem length in hip revisions with impaction bone grafting does not increase the risk of peri-prosthetic fractures, instead, reconstitutes the bone stock. This questions the conventional principle of bypassing the distal cavitation of femur by 2 cortical diameters with the use of long stem. In our experience, a good proximal femur support is key to performance of standard length cemented stems in revision for aseptic loosening irrespective of grade of distal cavitation for cavitatory defects of femur when treated with impaction bone grafting.

Introduction

Osteosynthesis to conserve femoral head following neck of femur (NOF) fractures has reported failure rates of 36 to 47% at 2 years. However, the long-term outcomes of THAs performed for failed osteosynthesis is yet to be elucidated. This study aims to report on long term outcome of primary THAs post failed osteosynthesis for NOF fracture.

With increasing burden of revision hip arthroplasty, one of the major challenge is the management of bone loss associated with previous multiple surgeries. Proximal femoral replacement (PFR) has already been popularised for tumour surgeries. The inherent advantages of PFR over allograft –prosthesis system, which is the other option for addressing severe bone loss include, early weight bearing and avoidance of non-union and disease transmission. Our study explores PFR as a possible solution for the management of complex hip revisions. Thirty consecutive hips (29 patients) that underwent PFR between January 2009 and December 2015 were reviewed retrospectively for their clinical and radiological outcomes. The Stanmore METS system was used in all these patients.

Mean age at the index surgery (PFR) was 72.69 years (range 50–89) with number of previous hip arthroplasties ranging from 1–5. At mean follow up of 32.27 months, there were no peri-prosthetic fractures and no mechanical failure of the implants. Clearance of infection was achieved in 80% of cases. There was 1 early failure due to intra-operative perforation of femoral canal needing further revision and two were revised for deep infection. Instability was noted in 26.7% (8) of the hips, of which, 87.5% (7) needed further revision with constrained sockets. Out of these 8 hips with instability, 5 had pre-operative infection. Deep infection was noted in 20% (6) of the hips, of which, 5 were primarily revised with PFR for septic loosening. However, further surgeries were essential for only 3 patients. One patient has symptomatic aseptic acetabular loosening and 1 had asymptomatic progressive femoral side loosening (lost to follow up).

Severe proximal femoral bone loss in complex revision arthroplasties has necessitated the use of PFR prosthesis. Our study supports the fact that PFR is probably a mechanically viable option for complex revisions. Significant numbers of dislocations and infections could be attributed to the poor soft tissue envelope around the hip. Further surgical techniques in the form use of dual mobility cups and silver coated PFR implants need to be explored.

Prosthetic joint infection continues to remain a diagnostic challenge for unhappy primary arthroplasty of hip and knees. There is increasing dependence upon alpha-defensin test to make key decisions like whether to revise or not & to decide between one-stage versus two-stage.

Background

One of the major concerns of hinge knees have been reported in literature is mechanical failure. Failure in the form of component fracture (2–10%) and hinge dislocation/ failure are worrisome. In addition, higher risk of aseptic loosening with hinge knee prosthesis has been attributed to stress transfer at bone cement interface.

In patients with primary hip replacement for previous infective arthritis the risk of recurrence of infection is of major concern. In addition, the safe time interval post infective arthritis for primary hip replacement is not known.

Clinical & radiological results of consecutive series of 80 primary hip replacements performed for septic / tuberculous arthritis at Wrightington hospital from 1970 to 2008. Data was collected till latest follow up. Re-infection or revision for any reason was considered as primary end point for survivorship.

Average age at primary hip replacement was 55.55 years (24 – 75). Mean follow up was 14.47 years (2–41). Twelve patients in septic hip group (n=42) needed revision out of which 6 (14%) were for infection. The survival rate for recent septic arthritis group (<10 years) was 60% at 7.5 years, whereas in old septic arthritis group (>10 years) it was 94.45% at 15.3 years, considering infection as end point. The survival rate was 60% for recent septic arthritis and 78.13% for old septic arthritis group over the same period of time considering revision for any reason as end point. In tuberculous group (n=38), the survival rate was 76.32% at 14.5 years of follow up, considering revision for any reason as end point.

Significantly high re-infection rate in patients with recent septic arthritis was noted. No recurrence of infection in patients with old septic arthritis. No reactivation of tuberculosis in tuberculous arthritis group.

This is the largest series with longest follow-up on primary total hip replacement for infective arthritis till date. Recent septic arthritis (<10Y) was a statistically high risk factor for recurrence of infection. Old septic arthritis is reasonably safe with 94.45% success rate at 15 years follow up. Old tuberculous arthritis is not a risk factor for hip replacement

The choice of stem length in total hip revision with impaction bone grafting of femur is essentially based upon the grade of cavitation of femur and surgeon's preference. The standard length stem has been often critiqued for the apprehension of peri-prosthetic fracture. Our study highlights the importance of proximal bone stock rather than distal cavitation in determining the length of femoral stem.

168 total hip revisions of 162 patients with impaction bone grafting and cemented standard C-stem (done with standardized technique) between 1995 and 2008 at a tertiary referral centre were included. Revisions for infection and segmental bone defects were excluded. Serial radiographs were retrospectively analysed by two people independently, using Endoklinik classification, Gruen zones and more and outcomes were analysed.

Mean follow-up of the 168 revision hips was 10.5 years (range 5 – 19.1 years). 14 patients (8.3%) were re-revised, reasons being, persistent deep infection (1.8%), repeated dislocations (1.2%), cup loosening (4.8%) and stem loosening (1.2%). Only 1 patient (0.6%) was re-revised due to stem loosening alone. No peri-prosthetic fractures or stem breakage were identified.

Use of standard stem length in hip revisions with impaction bone grafting doesn't increase the risk of peri-prosthetic fractures even during long term follow up period. This questions the principle of bypassing the distal cavitation of femur by 2 cortical diameters with the use of long stem. In our experience, a good proximal femur support aids in the performance of standard length cemented stems in revision for aseptic loosening irrespective of grade of distal cavitation for cavitory defects of femur treated with impaction bone grafting.

Optimal management of acute patellar dislocation is still a topic of debate. Although, conventionally it has been managed by non-operative measures, recent literature recommends operative treatment to prevent re-dislocations. Our study recommends that results of non-operative measures comparable to that of operative management.

Our study is the retrospective with 46 consecutive patients (47 knees) of first time patellar dislocation managed between 2012 and 2014. The study methodology highlighted upon the etiology, mechanism of injury and other characteristics of first time dislocations and also analysed outcomes of conservative management including re-dislocation rates. The duration of follow up ranged from 1 to 4 years.

Average age at first-time dislocation was 23 years (Range 10–62 years). Male:Female ratio was 30:17. Twisting injury was the commonest cause. 1 patient required open reduction but all others relocated spontaneously or had successful closed reduction. Medial Patello-Femoral Ligament injury was frequent associated feature. 11 knees (24%) re-dislocated during follow up. Age was the significant risk factor for re-dislocations. All patients with re-dislocation were less than 30 years old. Maximum redislocations happened between 6 months to 1 year after index dislocation. Skeletal abnormality was the commonest pathology in re-dislocators. Only 4 patients (8.6%) finally required surgical intervention. One patient had persistent knee pain as a complication.

Conservative management of primary patellar dislocation is successful in majority of patients. Surgery should be reserved for the carefully selected patients with specific indications.

Distal femoral replacement is an operation long considered as salvage operation for neoplastic conditions. Outcomes of this procedure for difficult knee revisions with bone loss of distal femur have been sparsely reported.

We present the early results of complex revision knee arthroplasty using distal femoral replacement implant, performed for severe osteolysis and bone loss.

Retrospective review of clinic and radiological results of 25 consecutive patients operated at single centre between January 2010 and December 2014. All patients had single type of implant. All data was collected till the latest follow up. Re-revision for any reason was considered as primary end point.

Mean age at surgery was 72.2 years (range 51 – 85 years). Average number of previous knee replacements was 2.28 (range 1 to 6). Most common indications were infection, aseptic loosening and peri-prosthetic fracture. Average follow up was 24.5 months (range: 3–63 months). 1 patient died 8 months post-op due to unrelated reasons. Re-revision rate was 2/25 (8%) during this period. One was re-revised for aseptic loosening and one was revised for peri-prosthetic fracture of femur. Two other peri-prosthetic fractures were managed by open reduction and internal fixation. All 3 peri-prosthetic fractures occurred with low energy trauma.

It is noteworthy that there was no hinge or mechanical failures of the implant. Peri-prosthetic fracture in 12% of patients in this series is of concern. There are no similar studies to compare this data with. The length of the stem, type of fixation of the stem, weight of the distal femoral component of implant can be postulated as factors contributing to risk of peri-prosthetic fracture.

Primary total hip replacement (THR) in patients with abnormal/altered proximal femoral anatomy/narrow canals presents a technical challenge. There are only limited standard prosthetic stems available to deal with narrow canals or abnormal morphology. Many prefer to use expensive custom implants which often have a lag time to manufacture and do not always have long term published outcomes.

We present results of the Asian C-stem (which is a standard implant available on the shelf) used in patients predominantly of Caucasian origin with abnormal proximal femoral anatomy.

We retrospectively reviewed clinic-radiological results of 131 patients (131 stems) who underwent primary THR using Asian C-stem at Wrightington Hospital till their latest follow up. Revision for any reason was considered as primary end point.

Mean age at surgery was 50.8 years (16 – 80). The 2 commonest indications were primary osteoarthritis (66 patients) and hip dysplasia (54 patients). Mean follow up was 43.5 months with a minimum follow up of 12 months and maximum follow up of 97 months. There were 2 recurrent dislocations and 1 hip subluxed twice. One dislocation needed revision surgery. 1 patient underwent acetabular revision for loosening. There was no stem failure, obvious loosening or loss of fixation in any patients in our series with regards to the Asian C-stem. There were no infections and intra-operative perforations or fractures.

C-stem Asian is a reliable implant for patients undergoing THR with abnormal proximal femoral anatomy or narrow canals. Long term follow up is essential.