- See:
Total Hip Replacement Menu:
- IntraOperative Frx:
- frx may occurr early while the attempt to dislocate hip is made;
- most postoperative femoral fractures can be prevented by avoiding injury to the bone during the original THR procedure;
- bone lysis from secondary aseptic loosening may significantly compromise strength of the femur and can lead to eventual frx;
- prevention of frx:
-
osteotomy of the trochanter before dislocation may reduce the force necessary for dislocation and thereby reduce the risk of frx;
- fragile bone of elderly pts and of pts with RA or disuse osteoporosis may be frxd by moderate rotational force;
- when resistance is met in attempting dislocation in these pts,
psoas tendon & more of capsule must be released;
- to dislocate hip posteriorly, partial transverse section of fascia lata &
maximus insertion may be necessary as well as release of tight, fibrotic band
along posterior edge of
medius;
- Frx Occurring in the Post Op Period:
- risk factors:
- inadequate calcar cancellous bone removal (w/ subsequent calcar resorption);
- varus positioning of the stem;
- lateral stem nicks produced by drilling for greater trochanteric wires;
- progressive
osteolysis;
-
vancouver classification:
-
type B frx: fractures occurring at or near the distal tip of
a hip prosthesis with a stable femoral stem (Vancouver type-B fractures)
-
type-B1 periprosthetic fractures:
-
defined as a fractures occurring at or near the distal tip of
a prosthesis with a stable femoral stem;
- associated with
the most complications of all of the fracture types because
of the inherently unstable fracture pattern;
-
type-B2:
- fractures occur in the same region with a loose stem
- type-B3:
- fractures occur with a loose stem where the proximal bone is of poor quality and/or severely comminuted
- references:
-
Classification of the hip.
-
Periprosthetic fractures of the femur. An analysis of 93 fractures
- Treatment protocol for proximal femoral periprosthetic fractures. J Bone Joint Surg Am 2004;86:8-16.
- managment:
- management depends on frx location, fixation of the prosthesis, and amount of displacement;
- in general, if the prosthesis is well fixed and if the fracture is minimally displaced, a trial of non operative treatment is indicated;
- femoral shaft perforations:
- need to bypass perforation by at least one and one half shaft diameters in order to reduce risk of shaft frx through the perforation;
- clinical recommendations have been to use a femoral component that ends 2-3 shaft diameters distal to the perforation;
- proximal femur frx;
- frx usually cannot occur unless there is loss of fixation of proximal femoral component;
- frx may have produced disruption of the bone cement prosthesis interface or there may have been preexisting loosening;
- requires revision of the femoral component;
-
example of femur frx occuring distal to the stem tip, which healed with use of traction and a cast brace;
- even though the fracture was angulated, the clinical result was good;
- long oblique frx at tip of prosthesis:
- more amenable to treatment in traction w/ subsequent cast bracing, if good alignment can be maintained;
- the main complication of non operative treatment is mal-alignment;
- short oblique frx at stemp tip: 
- arises due to a stress riser effect between prosthesis and bone;
- these frx are at high risk for displacement, shortening, & non union;
- not amenable to closed treatment;
-
loose component:
- using large uncemented prosthesis & obtaining stability in diaphyseal
region is often successful treatment of these fractures;
-
well fixed component:
- if component appears to be well fixed, consider leaving the prosthesis in place, and managing the fracture with a plate;
- proximal to the femoral component, the plate is secured w/ unicortical screws or with cerclage wires;
- ref:
Locking Compression Plate Fixation of Vancouver Type-B1 Periprosthetic Femoral Fractures
-
bone distruction:
- w/ extensive bone destruction is such that large allograft is needed;
- femoral cortical allograft may be applied to the medial femoral cortex and is secured by a laterally applied plate;
- above the level of the prosthesis the allograft is secured w/ cerclage wires;
- medial cortical allograft is applied thru an extended medial approach;
- this treatment strategy often produces allograft healing by 5 months unless the patient has had previous stripping the femoral periosteum in
which case non union is possible;
- Cerclage Fixation Techniques: (from Cheng et al 1993)
- Hairpin Cerclage Knot
- is significantly stronger than other fixation techniques;
- technique:
- wire is bent into a "U" shape;
- "U" is then passed around one end of the bone;
- one of the free ends of the wire is passed thru the "U" of the loop, and then the free ends of the wire are tension w/ a single throw of a square knot;
- Harris Wire Tightener:
- single throw of a square knot is thrown and is then tensioned w/ the Harris wire tightener;
- wire is twisted 180 deg while under tension (more twisting may break wire);
- Harris tightener is released and final twisting is completed with pliers;
- references:
- A comparison of the strength and stability of six techniques of cerclage wire fixation for fractures. Cheng, J. Orthop. Trauma. 1993. Vol 7, No 3. p 221-225.
Management of intraoperative femur fracture associated with revision hip arthroplasty. Christenen CM, Seger BM, and Schultz RB. CORR 248: 177, 1989.
Fracture of the ipsilateral femur in patients with total hip replacement. JBJS 63-A. 1435, 1981.
The uncemented total hip arthroplasty. Intraoperative femoral fractures.
Femoral fracture during non-cemented total hip arthroplasty.
Treatment of proximal femur fractures associated with total hip arthroplasty. H Montijo et al. J. Arthroplasty. Vol 4. 1989. p 115-123.
The role of allografts in the treatment of periprosthetic femoral fractures. HP Chandler and RG Tigges. JBJS. Vol 79-A. No 9. Sep 1997. p 1422.
Treatment of Periprosthetic Femoral Fractures Following Total Hip Arthroplasty with Femoral Component Revision.
Intraoperative Fracture of the Femur in Revision Total Hip Arthroplasty with a Diaphyseal Fitting Stem.
Three Hundred and Twenty-one Periprosthetic Femoral Fractures.
Intraoperative fracture of the femur in revision total hip arthroplasty with a diaphyseal fitting stem.
Fixation of periprosthetic femoral shaft fractures adjacent to a well-fixed femoral stem with reversed distal femoral locking plate.
