Retrograde intramedullary nailing with a blocking pin technique for reduction of periprosthetic supracondylar femoral fracture after total knee arthroplasty: technical note with a compatibility chart of the nail to femoral component

KNEE PERIPROSTHETIC FRACTURES IN THE ELDERLY: CURRENT CONCEPT

Periprosthetic fractures around total knee arthroplasty in elderly represent an emerging cause of implant revision and their incidence seems destined to further increase in the upcoming years, considering the ever-increasing number of implanted prostheses. These are complex injuries with very high complication rates. It has been estimated that the incidence of femoral periprosthetic fractures after T.K.A. ranged between 0,3 to 2,5%, but increases up to 38% when considering revision T.K.A. Patient-related risk factors for T.K.A. periprosthetic fracture (T.K.A.P.F.) include osteoporosis, age, female sex, revision arthroplasty and peri-implant osteolysis. The grate debate concerns the choice of the most appropriate fixation device for T.K.A.P.F.: closed or open reduction with internal fixation with either locked plate or intramedullary nail is the most commonly used for treating these fractures. Success of these methods depends on the fracture pattern, the stability of implants, and the patient’s bone quality which is often poor in elderly, thus resulting in high complication rates. Conversely, a revision of T.K.A. (R.T.K.A.) should be considered in case of prosthetic component instability, severe comminution or metaphyseal extension of the fracture (that precludes a good fixation), previous treatments failure and severe malalignment of T.K.A. Instead megaprosthesis and allograft-prosthesis composite are necessary in case of sever bone loss. Considering the variability of the clinical scenario of T.K.A.P.F., this complex injury requires and experienced and comprehensive approach based on both facture fixation and/or revision arthroplasty.

Outcomes of periprosthetic distal femur fractures following total knee arthroplasty: Intramedullary nailing versus plating

BACKGROUND

Periprosthetic distal femur fractures (PPDFFs) present a challenge in terms of optimizing fixation in patients with poor bone quality and limited bone stock. The main treatment options include laterally based plating and intramedullary nailing. We hypothesized that treatment of PPDFFs with intramedullary nails would result in improved union rate, fewer complications, and an equivalent rate of malalignment compared to plating.

MATERIALS AND METHODS

Cases of PPDFFs were identified through a query of our institutional trauma database between 2011-2018. Adult patients (>18 years) were included if they sustained a fracture of the distal femur around a total knee arthroplasty (TKA) that was not initially treated at another institution. The anatomic lateral distal femoral angle (aLDFA) and the anatomic posterior distal femoral angle (aPDFA) were measured on the follow-up radiographs.

RESULTS

Ninety-seven PPDFFs in 97 patients, with a mean age of 76 years and 74% female were identified. Plating was used in 74 patients (76%) and 23 patients (24%) were treated with intramedullary nailing. Extension deformity in the sagittal plane was more common following intramedullary nailing compared to plating (10/23 nailing versus 10/74 plating) (p=0.002). There were 12 reoperations (12/75, 16%), and the method of fixation was not associated with rate of reoperation (p=0.9).

CONCLUSION

Intramedullary nailing was associated with an increased risk of malalignment, most commonly an extension deformity, in this series. However, malalignment was not associated with worse outcomes.

Periprosthetic fractures of the knee: a comprehensive review

Demographic changes have resulted in an increase in the number of older patients diagnosed with degenerative joint disease. Developments in the field of joint arthroplasty allow a broader population to improve their lifestyles. An increased demand for knee arthroplasty has led to a rise in operations performed worldwide. Although there has been a constant propagation of technology and an increase in medical staffing at a professional level, many patients still encounter complications. Though rare, these factors may lead to life-threatening scenarios and a devastating effect on the success of the operation. One such rare complication includes periprosthetic fractures around the knee, a complex injury which requires a cautious and experienced approach. In this review, we analyze the prevalence, risk factors and classification, investigation and treatment options for periprosthetic fractures with total knee arthroplasty.

Malalignment in intramedullary nailing. How to achieve and to maintain correct reduction?

Intramedullary nailing has become the standard for the treatment of long bones diaphyseal fractures. Modern techniques of locking have further enlarged the primary indications to more proximal and distal fractures relying upon a former correct alignment. Nevertheless, residual deformities are not rare as once the nail has left the narrow diaphyseal canal and comes into the wider metaphysis, it may follow an unwished trajectory. There is also a chance for malreduction in diapyhseal fractures. The more complex the fracture is, the more difficult its reduction, not only for the alignment of the proximal or the distal part of bone in relation to the diaphysis, but also correct rotation and length. In this paper, we analyze recommended techniques to achieve accurate bone fracture reduction, to avoid post-operative deformities combined with correct implant insertion.

Total Hip Arthroplasty for Implant Rupture after Surgery for Atypical Subtrochanteric Femoral Fracture

Treatment methods for delayed union and nonunion of atypical femoral fracture are still controversial. Moreover, no treatment method has been established for implant rupture caused by delayed union and nonunion. We encountered a 74-year-old female in whom nonunion-induced implant rupture occurred after treatment of atypical subtrochanteric femoral fracture with internal fixation using a long femoral nail. It was unlikely that sufficient fixation could be obtained by repeating osteosynthesis alone. Moreover, the patient was elderly and early weight-bearing activity was essential for early recovery of ADL. Based on these reasons, we selected one-stage surgery with total hip arthroplasty and osteosynthesis with inverted condylar locking plate as salvage procedures. Bone union was achieved at 6 months after surgery. This case illustrated that osteosynthesis-combined one-staged total hip arthroplasty could be considered as one of the options for nonunion-induced implant rupture of atypical femoral subtrochanteric fracture.