The Use of Plaster of Paris to Fill Defects in Bone
LEONARD F. PELTIER, M.D., PH.D.,00 EARLY. BICKEL, M.D., RoBERT LILLO, M.D., MAUNG SoE THEIN, M.D., B.S.
From the Department of Surgery and the Division of Orthopedic Surgery, University of Minnesota Medical School, Minneapolis, Minnesota
FIG. I. A column and tablets of plaster of paris.
IN APRIL 1953, Kovacevic 8 reported three patients in whom diaphysectomy of the tibia was carried out for the treatment of hematogenous osteomyelitis. At the time of resection, the large defects in the shaft of the tibiae were filled with columns of plas ter of paris to which sulfonamides and peni cillin had been added. The results were startling: primary healing of the operative wounds, slow absorption and disappear ance of the plaster, and, finally, bony re generation through the area of the defect. Intrigued by the inherent possibilities of such a procedure, we have studied the method in the animal laboratory. An initial report of our experiments has been re ported elsewhere.12
FIG. II. Serum calcium levels in four dogs in which plaster of paris columns were inserted into subperiosteal defects in the radius.
Plaster of paris, commercial grade, was mixed with water, poured into moulds made of wax paper or aluminum foil, and allowed to set. The moulds were then re moved. The columns measured 2 X 15 em. and contained some air bubbles as imper fections. A number of plaster of paris hypo tablets were made using a tablet mould (Fig. I). A few columns of plaster were made with plaster of paris of dental grade.
All of the plaster columns and tablets were sterilized by dry heat in an oven at 300° C. for 24 hours.
Mongrel dogs of either sex and more than one year of age were used in all experi ments. All operations were pedormed with the animal anesthetized with intravenous sodium pentobarbital. A rubber tourniquet was used to provide a bloodless field. The bones were exposed through muscle split ting incisions. When the periosteum was re moved the muscle attachments were freed by sharp dissection. When the periosteum was left behind, it was incised longitudinally and stripped from the bone. Sections of the shaft of the radius were cut with a sharp osteotome. No attempt was made to recon stitute the periosteum when present during closure of the wounds. In fact, this would have been impossible since the tissue was badly frayed and shredded. The muscles were approximated with interrupted catgut sutures; the skin, with interrupted silk su tures. Roentgenograms were then taken and the limbs splinted with padded splints. The tourniquets were removed. No antibiotic drugs were given to any of the animals. The splints were left in place for three to four weeks.
In some of the animals, blood for calcium determinations was taken preoperatively and at intervals postoperatively. The serum calcium was determined by Clark and Col lip’s modification of Tisdall’s method.2
Further roentgenograms were taken at intervals postoperatively and at the time of sacrifice. At this time the entire bone was removed and blocks were cut from the area of the defect. Sections were cut and stained with hematoxylin and eosin,
TYPES OF OPERATION
1. A section of the shaft of the radius was removed from its middle third leaving the periosteum behind.
2. A similar subperiosteal resection of the radius was made and a column of plaster of paris was inserted into the defect.
3. A section of the radius with its periosteum was excised,
PELTIER, BICKEL, LILLO AND THEIN
FIG. IIIA————————————–FIG. IIIB
FIG. III. Dog #1125 a) at the completion of the operation, b) 4 weeks postoperatively, c) at the time of sacrifice, 98 days postoperatively, d) the reconstituted radius with the segment of bone excised at the operation.
PLASTER OF PARIS TO FILL DEFECTS IN BONE
FIG. IVA.—————————————————FIG. IVB.
FIG. IV. Dog #1126 a) at the completion of the operation, b) 4 the weeks postoperatively, c) at time of sacrifice, 96 days postoperatively, d) section through the regenerated area.
4. A section of radius with its periosteum was excised, and the defect filled with a column of plaster of paris.
5. A window was cut in the lateral cortex of the distal femur. A large amount of can cellous bone was curretted from the meta physis. The cavity was then packed with tablets of plaster of paris.
The results of the experiments are summarized in Tables I through V.
Wound healing progressed to primary union in almost every animal. The insertion of a large mass of plaster of paris did not appear to be associated with an increase in the number of wound infections. The use of
PELTIER, BICKEL, LILLO AND THEIN Annals of Surgery
antibiotics administered systemically or as additives in the plaster did not seem to be necessary to insure wound healing in clean wounds when good surgical technic is employed.
Complete or partial absorption of the plaster of paris, as judged by the roentgeno grams, occurred in all animals in which it was used. The absorption of the plaster was accompanied by an elevation of the serum calcium level ( Fig. II ).
Microscopic sections through the areas of bone defect into which plaster of paris had been implanted showed that the ab sorption of this material was associated with large numbers of osteoclasts. Small particles of plaster of paris were seen occasionally incorporated directly into the bone matrix. Most important, the plaster of paris did not elicit any foreign body reaction. The re generated bone appeared to be normal in every respect.
Of the 11 dogs with subperiosteal defects in the radius, one showed partial regenera tion of the defect; three, complete regenera tion (Table 1).
Among 14 dogs with subperiosteal defects of the radius into which columns of plaster of paris had been inserted, six showed partial regeneration of the defects; three, complete regeneration (Figs. III, IV, V, VI. Table II).
In none of the nine dogs with defects of bone and periosteum was there any evi dence of bone regeneration (Table III).
In two of nine dogs with bone and peri osteal defects into which plaster columns were inserted, there was partial regenera tion of the defect (Table IV).
In the group of six dogs in which plaster of paris tablets were packed into meta physeal defects, complete regeneration oc curred in five (Table V. Fig. VII).
FIG. V. Dog #1174 a) condition after 28 days, b) section showing the absorption of the plaster and new bone fom1ation.
FIG. VI. Dog #721 a) showing fracture of ulna and excessive callus formation, b) section showing particles of plaster of paris incorporated into the callus and new bone.
A variety of calcium salts and combina tions of calcium and phosphate have been used in experimental animals to fill bone defects. The results have been equivocal. Key,6 StewarP7 and Haldeman and Moore 4 were unable to find any bone regeneration associated with the insertion of calcium salts into bone defects in animals. Albee and Morrison/ Murray,9 Shands/6 Schram and Fosdick/5 and Ray and Ward,14 how ever, were more encouraged. In their experi ments new bone formation accompanied the insertion of calcium salts into bone defects. In one observation, all of these investiga tors are in agreement. The implantation of the calcium salts into the bone has no ap parent deleterious effect upon the surround ing bone; they are accepted kindly by the tissue; and are gradually absorbed and dis appear from the site of implantation.
The use of plaster of paris ( CaSO4 ) to fill defects in bone arising in association with the resection of bone tumors, tubercu lous foci, areas of osteomyelitis, or about un united fractures has had a fairly extensive trial by European surgeons. Oehlecker 11 in 1925 urged that more surgeons use plas ter of paris to fill bone defects remaining after the treatment of fibrous dysplasia and other benign localized bone tumors. Stim ulated by Oehlecker’s report, Kofmann, 7also in 1925, reported upon the follow up of a case operated upon in 1912 in which an area of osteomyelitis had been excised and replaced with plaster, with a restitution of the normal bone architecture. Gunnar Ny strom 10 and Edberg 3also reported satis factory results following the use of plaster to fill bone defects. Petrova 13 carried out experiments in dogs in which plaster of PELTIER, BICKEL, LILLO AND THEIN Annals of Surgery
FIG. VII. Dog #15 a) flaster tablets after in sertion in the metaphysis o the femur, b) appear ance 75 days postoperatively paris mixed with antiseptics was success fully used to replace bone defects in in fected and in aseptic wounds.
More recently, the Swiss surgeon, Hauptli,5 has reported an extensive clinical experience with the use of plaster of paris in the treatment of non-union and a variety of bone tumors. The most recent report is that of Kovacevic 8 which prompted this study.
All of these authors, as far as can be determined, used fresh plaster, mixed at the time of operation and placed in the wound in the moist state. We found this a difficult thing to do without spillage, and have pre ferred to work with the more conveniently hardened plaster columns or pellets.
In none of these reports have any com plications due to the plaster itself been noted. The authors express a feeling of sat isfaction with the method and have urged its more widespread application. The resuits of the animal experiments reported here confirm their observations as to the safety and success of the technic. Our only concern has been the rise in the blood cal cium associated with the absorption of the plaster and the possibility of nephrocal cinosis or renal calculi appearing in asso ciation with the use of large quantities of plaster.
From these experiments it can be seen that the plaster of paris itself does not stim ulate osteogenesis. Its chief effect may be the mechanical one of preventing the col lapse of the periosteal tube and favoring re generation in this way. There is no doubt however that subperiosteal resections in which plaster of paris columns were in serted regenerated, in whole or in part, more frequently than was the case in sub periosteal resections alone.
PLASTER OF PARIS TO FILL DEFECTS IN BONE 69
The major point of interest in these ex periments was the behavior of the plaster of paris. It does not prejudice wound healing nor provoke a foreign body reaction. It is slowly absorbed and disappears from the site of implantation. This material may find a greater application in clinical surgery when its behavior becomes more widely appreciated.
Plaster of paris ( CaSO4) is absorbed from areas of implantation in bone and is well tolerated by the tissue. In association with the absorption of the plaster, bony re generation from endosteal and periosteal cells occurs.
1. Albee, F. H. and H. F. Morrison: Studies in Bone Growth: Triple Calcium Phosphate as a Stimulus to Osteogenesis. Annals of Surg., 71: 32, 1920. Rivanol-Plaster-Porridge. Acta Chirurgica
2. Clark , E. P. and J. B. Collip: A Study of the Tisdall Method for the Determination of Blood Serum Calcium with a Suggested Modification. J. of Biological Chemistry, 63: 461, 1925.
3. Edberg, E.: Some Experiences of Filling Os seous Cavities with Plaster. Acta Chirurgica Scandinavica, 67: 313, 1930.
4. Haldeman, K. 0. and J. M. Moore: Influence of a Local Excess of Calcium and Phosphorus on the Healing of Fractures. Archives of Surgery, 29: 385, 1934.
5. Hauptli, 0.: Die Gipsplombe zur Ausfullung von Fehlendem Knochengewebe. Schweizer ische Medizinische Wochenschrift, 82: 161, 1952.
6. Key, J. A.: The EHect of a Local Calcium Deposit on Osteogenesis and Healing of Frac tures. Journal of Bone and Joint Surgery, 16: 176, 1934.
7. Kofrnann, S.: Gips als Plombenmaterial. Zen tralblatt fiir Chirurgie, 52: 1817, 1925.
8. Kovacevic, B.: Ein Beitrag zum Problem der hamatogenen Osteomyelitis. Archiv fiir Klin ische Chirurgie, 276: 432, 1953.
9. Murray, C. R.: The Repair of Fractures. Min nesota Medicine, 13: 137, 1930.
10. Nystrom, G.: Plugging of Bone Cavities with Scandinavica, 63: 296, 1928.
11. Oehlecker, Franz: Ueber Knochenplombe. Zentralblatt fiir Chirurgie, 52: 993, 1925.
12. Peltier, L. F. and R. Lillo: The Substitution of Plaster of Paris Rods for Portions of the Diaphysis of the Radius in Dogs. Surgical Forum, Vol. VI, pp. 556, Amer. College of Surgeons, Chicago, Illinois, 1956.
13. Petrova, A.: Gipsfiillung von Knochenhohlen bei Osteomyelitis. Zentralorgan fiir die gesamte Chirurgie, 43: 485, 1928.
14. Ray, R. D. and A. A. Ward, Jr.: A Preliminary Report on Studies of Basic Calcium Phos phate in Bone Replacement. Surgical Forum, Clinical Congress of the Amer. College of Surgeons, 1951. W. B. Saunders Co., Phil adelphia, 1952.
15. Schram, W. R. and L. S. Fosdick: Studies in Bone Healing. J. of Oral Surgery, 1: 191, 1943.
16. Shands, A. R., Jr.: Studies in Bone Formation: The EHect of the Local Presence of Calcium Salts on Osteogenesis. J. of Bone and Joint Surgery, 19: 1065, 1937.
17. Stewart, W. J.: Experimental Bone Regenera tion Using Lime Salts and Autogenous Grafts as Sources of Available Calcium. Surg., Gynec. & Obst., 59: 867, 1934.