Rupture of the quadriceps tendon was first reported in the English literature by Samuel in 1838. The quadriceps tendon usually ruptures transversely at the osteotendinous junction. The rupture often extends through the vastus intermedius, slightly proximal to the rupture of the rectus femoris tendon. The described repair is usually performed by horizontal mattress sutures placed in the vastus intermedius stump pulled anteriorly through the rectus femoris and tied distally through drill holes placed in the patella. The repair is reinforced by a local flap technique, or protected by a circumferential wire, strong nonabsorbable sutures, a Bunnell pull-out wire through the medial and lateral retineculum or less commonly, by a wire and bolt technique.1–3

Isolated vastus medialis obliquus (VMO) tendinous rupture is a very rare injury. Passing sutures pulled through bone tunnels with needles is cumbersome and possibly would need reinforcement and or protection as described in vastus intermedius and rectus femoris repair.

We describe a new method of fixation of the ruptured tendon with the use of absorbable anchor sutures (Duet anchor suture Bionx-Linvatec) that facilitates the surgical procedure without altering the postoperative care, rehabilitation, and complication rate.

MATERIALS AND METHODS

Three male patients, 24–36 years of age, diagnosed to have isolated ruptures of the VMO underwent surgical repair within 1 week of injury. The injuries occurred when lifting heavy weights during manual labor. The diagnosis was made clinically and confirmed by MRI scan (Fig. 1).

FIG. 1.:

Coronal, transverse and sagittal views confirming the isolated interruption of the VMO with intact MPFL.

Under tourniquet control, a medial parapatellar 8–10 cm incision at the distal end of the quadriceps muscle was used for exposure. The avulsed VMO tendon was easily identified (Fig. 2).

FIG. 2.:

The avulsed VMO of the superior medial aspect of the patella.

The insertion site of the tendon is cleaned of any tendon remnants and roughened to create a bone trough. Two absorbable anchor sutures (Duet anchor suture Bionx-Linvatec) were inserted into the superior medial aspect of the patella horizontally into the bone at the intended fixation site. The 2 anchor suture arms were used to bring the vastus obliquus tendon into opposition with the trough created in the patella. The knee is extended, and traction placed on the suture arms brings the tendon down to the bone. Tying the suture over the bone trough aligns the tendon and the patellar tracking is evaluated carefully. The wound is irrigated, the retinaculum is repaired with interrupted absorbable sutures and the skin and subcutaneous tissue is closed in a routine manner (Fig. 3).

FIG. 3.:

Absorbable anchor suture; suture arms of the anchor sutures inserted into the superior medial aspect of the patella; following repair, VMO restored into its anatomic position.

A cylinder cast is applied with the knee in extension for 4 weeks. Isometric quadriceps exercises are started as early as third day postoperative. Weight bearing with crutches is allowed at 2 weeks. After cast removal, a dial-locked brace is fitted, allowing a range of knee motion from 0 to 60 degrees; the range is increased 10–15 degrees each week for another 4 weeks. An aggressive strengthening program is essential for good functional recovery.

RESULTS

At an average final follow up of 26 months post repair (24–28 months), all 3 patients were satisfied. They had restoration of their normal activities with full active range of motion (Fig. 4).

FIG. 4.:

Full active range of motion noted at 5 months postoperatively.

There was return to full strength in extension when compard with the contra lateral normal side. All patients went back to weight lifting and manual labor activities. There were no immediate surgical postoperative complications and no re-ruptures during the follow-up period.

DISCUSSION

Isolated ruptures of the VMO are very rare injuries. The medial patellofemoral ligament, which lies within the intermediate layer of the medial retinaculum, typically attaches to the superior half of the patella, and is contiguous with the deep surface of the tendon of the VMO, is spared (Fig. 5).

FIG. 5.:

Anatomic relationship of the MPFL and the VMO.

MRI is helpful if the diagnosis is questionable and in determining whether the rupture is complete and/or is associated with medial patellofemoral ligament (MPFL) injury.

In quadriceps tendon rupture the advocated repair techniques advise reinforcement with a local flap technique or protection by a circumferential wire, strong nonabsorbable sutures, Bunnell pull-out wire through the medial and lateral retinaculum or, less commonly, by a wire and bolt technique.1–3

In isolated VMO ruptures passing sutures pulled through bone tunnels with needles is cumbersome and would possibly need reinforcement as described in quadriceps rupture.

We have assessed the use of absorbable anchor sutures to overcome the above. Duet anchor suture Bionx-Linvatec is a bioabsorbale screw-in suture anchor that is preloaded on a disposable inserter device with 2 nonabsorbable, braided, polyester #2 sutures. It is manufactured from Self-Reinforced (96/4D) PLA Copolymer that retains 90% strength through 20 weeks and completely resorbs over a period of several years in vivo. The absorption profile of the Copolymer allows the anchor to gradually loose strength as the collagen fibers of the repair form and gain strength. The insertion is relatively simple, and provides an excellent pull-out strength which is estimated at 217 N. The material strength eliminates bioabsorbable eyelet as a failure mode in repair construct, 406 N.4

In our 3 patients the repair was strong enough not to require any reinforcement, with no evidence of rerupture. The return to full range of motion was facilitated by early mobilization. There were no wound complications or infections.

CONCLUSIONS

We have presented our experience with use of the absorbable anchor sutures in the acute repair of VMO tendon ruptures. We feel that this technique simplifies the repair without altering the postoperative care, rehabilitation, and complication rate.

REFERENCES 1.Scuderi C. Ruptures of the quadriceps tendon: study of twenty tendon ruptures. Am J Surg 1958;95:626–634. 2.Francis KC. The surgical treatment of tears of the quadriceps tendon. Bull NY Orthop Hosp 1957;1:18. 3.McLaughlin HL, Francis KC. Operative repair of injuries to the quadriceps extensor mechanism. Am J Surg 1956;91:651–653. 4.Barber FA, Herbert MA, Richards DP. Sutures and suture anchors: update 2003. Arthroscopy 2003;19:985–990.