- Discussion:
- once femoral and acetabular components have been removed, residual cement can be removed from the femoral canal;
- it is better to move onto to the acetabular revision prior to cement removal since the cement will prevent blood loss from the canal;
- note: if gentamicin had been previously added to the component cement, then culture sample should be taken before the cement is disrupted (because
high levels of active gentamicin will be released);
- references: Gentamicin release from old cement during revision hip surgery. JW Powles et al. JBJS. Vol 80-B. No 4. July 1998. p 607.
- Proximal Cement Column:
- as with component removal, lateral exposure (just medial to the greater trochanter is essential) to avoid metaphyseal perforation;
- if necessary trochanteric osteotomy is performed;
- adequate, lateral exposure is also essential for distal cement removal;
- instruments: splittng chisel, osteotomes and reverse rake;
- high speed burr may be used to thin cement in areas of osteoporotic metaphyseal bone;
- if cement splits and leaves a pointed leading edge, the compound C chisel can break it up;
- Murphy's Law:
- if lateral cement column is not entirely removed, there will be a strong varus force applied to the long stem component (during insertion), which may
cause intraoperative femur fracture;
- Middle Cement Column:
- if femoral stem has been removed, leaving the cement column intact, consider screw insertion of an appropriately sized
sharp metal tap into the proximal cement column;
- after screwed into the proximal femur, the tap can then be hammered out;
- if only a proximal ring of bone is removed, consider re-insertion of metal tap more distally;
- cement is chipped away down to the level of the stem tip;
- w/ luck the residual cement is loose and can simply be pulled out;
- cement forceps are useful for at this stage;
- if large scallops, are present, cement chisels are used to go progressively down;
- remove cement as far distally as possible w/ osteotomes, which is possible for 10 to 15 cm down canal or upto area where stem tip was;
- remaining cement is removed with a high speed burr;
- when cement extends beyond curvature of femur, making straight access no longer possible, take great care to avoid perforation;
- cement can be safely removed more distally thru proximal femur if greater trochanter has be osteotomized or if flouroscopy has been used;
- whatever technique is used, a point is reached at which it is no longer safe to remove bone from above;
- Removal of Distal Cement Plug:
- w/ > 2 cm of cement entirely filling canal between stem tip & plug, consider using large windows;
- vastus is flapped forward and a windows is then cut length of the cement w/ a width of 1 cm;
- the cuts are angled so that the window is wedge shaped;
- Windows:
- Controled perforation. A safe method of cement removal from the femoral canal. Sydney SV and Mallory TH. CORR. 137: 96, 1978;
- Tips of the trade #29. Femoral windows for easy cement removal in hip revision surgery.
- Femoral cement removal in revision total hip arthroplasty. A biomechanical analysis.
- Surgical Instruments:
- Moreland Cement Hook:
- used to remove distal cement plug;
- this is curved on one side and flattended on the other;
- curved end is placed against the wall distally, w/ flattended side facing the femur;
- it is gently tapped with a hammer until it bypasses the cement;
- hook is then turned to face cement, and the handle is struck sharply with a slap hammer;
- Mueller Cement Reamers:
- smallest reamer is mounted on the T handle;
- w/ careful visualization of distal portion of femur in 3 dimensions, tip of the reamer is placed in center of cement mass and tapped with a hammer and twisted;
- this is continued until reamer penetrates the cement;
- if inserted off center, reamer can penetrate bone;
- larger reamers are progressively used until a small cement hook can be passed;
- cement hooks are then used to remove all residual cement;
- High speed burr can also be used but is best used under flourscopic control;
- Segmental Cement Extraction at Revision Total Hip Arthroplasty. (CORR 1992).
- contra-indications:
- femoral fracture, distal cement mantel flaring, extrusion of cement thru a previous cortical defect;
- equipement:
- a coated threaded rod which is longer than the cement mantle;
- technique:
- femoral stem is removed using standard techniques;
- a 0.64 cm drill bit is used to drill thru the distal cement plug;
- residual cement is cleaned w/ wire brush to remove any soft tissue membrane, and is then irrigated;
- canal is dried with gauze;
- cement is mixed at low temperature (to minimize viscosity) and is then injected into the medullary canal upto the level of the lesser trochanter;
- a threaded rod is then inserted into the center of the medullary canal;
- once the cement has hardened, the threaded rod is back out;
- threaded extraction rods are then inserted no more than 2 cm at a time;
- a slap hammer is used to sequentially remove small segments of cement;
Thermal Tissue Damage Caused by Ultrasonic Cement Removal from the Humerus.
Segmental cement extraction at revision total hip arthroplasty. D.J. Schurman MD CORR No 285 Dec, 1992 p 158.
Femoral cement removal in revision total hip arthroplasty: A biomechanical analysis. Dennis DA et al. CORR 220: 142, 1987.
Endoscopy for Cement Removal in Revision Arthroplasty of the Hip.
Methods of removing excess bone cement.
Persistent infection associated with residual cement after resection arthroplasty of the hip.
