Reconstruction of a cruciate ligament

In a process for surgically reconstructing the anterior cruciate ligament of the knee to restore its normal stability, the damaged ligament is removed and holes are formed in both the tibia and the femur. The holes extend through the knee joint with their adjacent ends terminating approximately at the points of origin of the removed ligament. A strip is partially severed from the patellar tendon, except at its lower end where it remains attached to the tibia. The tendon strip is shaped and sutured into a tubular configuration and fitted into an open-ended, tubular sleeve of Dacron open mesh fabric. The composite Dacron fabric and the tendon segment is inserted into the hole provided in the tibia, fitted through the knee joint and then advanced upwardly through the hole in the femur. The upper end of the composite insert is fastened in place by means of a bone member fitted into the upper end of the hole in the femur to wedge the upper end of the insert in fixed position.

BACKGROUND OF THE INVENTION 
The instability associated with anterior cruciate ligament rupture has 
created numerous problems and various possible solutions have been well 
documented in the literature. 
U.S. Pat. No. 3,953,896, dated May 4, 1976, dislcoses a prosthetic ligament 
to be used to replace a damaged cruciate ligament. In this patent, the 
prosthetic ligament includes a cylindrical central portion of polyethylene 
and threaded outer portions provided with bushings to protect the central 
portion from abrasion caused by skeletal flexing. Fasteners, in the form 
of nut members, are also provided to fasten the prosthesis within the 
skeletal apertures. 
U.S. Pat. No. 3,545,008, dated May 27, 1968, also discloses a tendon 
prosthesis which consists of a Dacron mesh sleeve sutured to the proximal 
ends of a ruptured tendon. The sleeve includes a mesh netting at its outer 
ends to encourage fibroblastic infiltration to occur between the severed 
ends of the tendon for anchoring the prosthesis to the tendon. 
U.S. Pat. No. 4,187,558, dated Feb. 12, 1980, relates to a prosthetic 
ligament positioned within a surgically prepared passageway in the bone, 
and a Dacron and/or Dacron and silicone strand is disclosed as a 
replacement for a cruciate ligament with Dacron velour fabric used as 
collars at the outer ends of the central portion to promote new tissue 
growth. 
U.S. Pat. No. 3,797,047, dated Mar. 19, 1974, discloses an artificial 
tendon material which consists of a tubular sheath of silicone elastomer 
with an inner tensile element of knitted fabric. 
U.S. Pat. No. 3,805,300, dated Apr. 23, 1974, teaches a tendon which is 
composed of a cord-like combination of silicone and Dacron strip with 
transverse openings for the natural tendon to be woven therethrough. 
In these prior art procedures, the damaged natural tendon is relaced with a 
synthetic member which is a biocompatible material, usually Dacron and/or 
silicone. One problem with these techniques is that the tendon prosthesis 
is essentially synthetic, except that some means is utilized to encourage 
functional anastomosis. For example: in the Bader U.S. Pat. No. 3,545,008, 
mesh flaps are sutured to the ends of the ruptured tendon and in the 
Alonso U.S. Pat. No. 3,805,300, the resected tendon is inter-woven through 
perforations in the synthetic cord member. 
The present invention involves the replacement of a cruciate ligament with 
a composite synthetic and biological structure to provide maximum 
mechanical and structural stability, both short and long-term, after 
surgical reconstruction. 
The principal object of this invention is to provide an improved method of 
surgically reconstructing a severely damaged or ruptured tendon. 
Another object of this invention is to provide for ligament augmentation 
particularly adapted to the anterior cruciate ligament.

Referring now in detail to the drawings, in FIG. 1 is shown an injured knee 
joint 4 being surgically prepared for anterior cruciate ligament 
reconstruction. The femur and tibia are represented at 6 and 8, 
respectively, and the fibula at 10. The medial collateral ligament and 
lateral collateral ligament are shown at 12 and 14. The anterior cruciate 
ligament is illustrated in broken line construction at 16 and the 
posterior cruciate ligament at 18. These ligaments are the primary 
ligaments which stabilize the knee joint and they extend diagonally at 
approximately right angles to each other and, hence, are referred to by 
the adjective "cruciate." The knee cap or patella is shown at 20 in FIG. 2 
and in phantom in FIG. 1. The meniscus is illustrated at 22. 
In the event of a torn or ruptured anterior cruciate ligament, serious knee 
joint instability invariably results and the prior art, as discussed 
above, discloses various techniques for attempting satisfactory 
restoration of normal knee joint stability. In accordance with my 
invention, the anterior cruciate ligament is replaced or reconstructed 
with a ligament augmentation composite in the following manner. 
The ruptured anterior cruciate ligament 16, shown in phantom, is first 
surgically removed and a strip 24 of tendon tissue is severed from the 
quadriceps mechanism, in particular the patella tendon, leaving it 
attached to the tibia at its lower end, as best illustrated in FIG. 2. The 
tissue for this strip is available in the inferior expanse of the 
quadriceps mechanism, and especially from that portion of the patellar 
tendon overlying the patella. A hole, channel or bore 26 is then drilled 
diagonally through the tibia, starting from a point adjacent the attached 
end of the strip 24 and terminating at approximately the same location as 
the point of connection of the cruciate ligament 16 to the tibia. A second 
hole, bore or channel 28 is drilled diagonally through the femoral condyle 
to approximately the point of connection of the ligament 16 to the femur. 
The holes 26 and 28 are drilled to be approximately in axial alignment 
along the same general line as that of the removed anterior cruciate 
ligament. 
The tendon strip 24 is then shaped and sutured into a tubular 
cross-sectional form, using absorbable suture material. This tubular 
tendon is next fitted within a unitary, seamless Dacron (polyethylene 
glycol terephthalate) mesh sleeve or sheath 30 (FIG. 3) about 8-12 mm in 
length and about 1 cm in cross-section, or approximately the same 
dimensions as the anterior cruciate ligament of the human knee. Some 
suturing may also be used to consolidate the inner biological segment and 
the outer synthetic component of the composite reconstructed ligament. 
Whenever feasible, this composite structure is further sheathed with the 
synovium membrane within the femoral intercondylar notch and infrapatellar 
fat pad. This is also accomplished by using absorbable suture material in 
order to make this composite member as similar as possible to the human 
anatomic anterior cruciate ligament, which has a synovial covering. 
The composite sleeve and tendon is then fitted upwardly through the hole 26 
in the tibia and the hole 28 in the femur until its terminal or free end 
is positioned at or near the outer end of hole 28, as best illustrated in 
FIG. 3, in which a central portion of the sleeve 30 is shown broken away. 
A plug or wedge 32 of bone, which is preferably removed surgically from 
the femoral condyle at the site through which the hole 28 is to be 
drilled, is used to fasten or secure the upper end of the reconstructed 
ligament in place within the bore 28. This is done by firmly wedging the 
upper end of the composite against the wall of the bore 28 with the bone 
plug 32, as illustrated in FIG. 3. 
The tubular composite structure, such as described above, is considered 
superior in both its mechanical strength and as a template to encourage 
fibroblastic ingrowth and ultimate longitudinal alignment of collagen 
fibers. The intraluminal tendonous segment 24 thus not only increases the 
overall strength of prosthesis but also increases fibrous ingrowth and 
maturation.