Quadriceps Tendon Rupture

By admin On Feb 25, 2024

Ovid: 5-Minute Orthopaedic Consult

Editors: Frassica, Frank J.; Sponseller, Paul D.; Wilckens, John H.

Title: 5-Minute Orthopaedic Consult, 2nd Edition

> Table of Contents > Quadriceps Tendon Rupture

Quadriceps Tendon Rupture

Carl Wierks MD

Michelle Cameron MD

Basics

Description

Rupture of the quadriceps tendon (knee extensor mechanism) results in an inability to extend the leg.
- In patients >40 years old, rupture may be secondary to tendon degeneration.
Classification:
- Complete versus incomplete

General Prevention

Stretching before athletics and thigh-strengthening exercises in patients with chronic tendinitis could provide some protection.

Epidemiology

A rare occurrence
Can occur in any age group
Affects males more than females

Risk Factors

Trauma, usually in the setting of an underlying chronic tendinitis
Medical conditions such as renal disease,
diabetes mellitus, gout, rheumatoid arthritis, chronic steroid use,
obesity, lupus, hyperparathyroidism, and dialysis
Previous total knee arthroplasty

Genetics

No known inheritance of predisposition to quadriceps tendon rupture

Etiology

Tendon rupture can occur:
- During attempts to regain balance to
  avoid a fall; maximum force can be placed across the quadriceps tendon
  when eccentric loading is placed on a semiflexed of knee.
- Secondary to direct or penetrating knee trauma

Associated Conditions

Meniscal or knee ligament damage

Diagnosis

Signs and Symptoms

Inability to extend the knee actively
Acute pain
Suprapatellar gap
Weak leg extension with partial rupture

History

Acute trauma
Attempt to regain balance before a fall, with a history of a chronic condition or tendinitis

Physical Exam

Inability to perform a straight-leg raise
Inability to actively extend the leg
Holding the knee in full extension may be
possible if the knee retinaculum is intact; patients should be asked to
extend the knee from the flexed position.
Palpation of a gap 1–2 cm proximal to the superior pole of the patellar; examination of the contralateral knee is important.
Nearly full passive ROM is possible.
Routine knee ligament examination is performed to ensure that no other damage has occurred.

Tests

Imaging

Routine AP and lateral radiographs:
- The patella is displaced distally on lateral radiographs.
- May see calcifications in the presence of chronic tendinitis
MRI or ultrasound may be useful when the physical examination is inconclusive.

Pathological Findings

Degenerative changes are seen in the quadriceps tendon in patients with collagen vascular disease and in persons >40 years.

Differential Diagnosis

Patellar fracture
Patellar tendon rupture
Knee ligament injury
Quadriceps muscle rupture

Treatment

General Measures

Partial tears with an intact extensor mechanism are rare.
- Treated nonoperatively
- The knee is immobilized in full extension with a brace or cast.
- Protected ROM and strength training is begun after 6 weeks.
- Weightbearing as tolerated with the knee braced
Complete tears:
- Repaired surgically
- Ideally, operative repair should be performed as soon as possible.
- Quadriceps ruptures also may require
  quadriceps lengthening and augmentation because muscle retraction can
  occur and the muscle can adhere to the femur (tendon cannot be
  mobilized) (1).
- Quadriceps sets and straight-leg raises in a knee immobilizer are begun immediately after surgery.

Physical Therapy

Therapy is best begun early, 1–2 weeks after repair.
Passive ROM and active flexion exercises are emphasized.
May wean from use of the knee brace with improved quadriceps strength (6–8 weeks)

Medication

NSAIDs are helpful for reducing swelling and pain.
Narcotics may be added for analgesia.

Surgery

Primary end-to-patella repair:
- Results are better with early intervention.
- Delayed repairs may require augmentation or interpositional tendon graft.

P.351

Follow-up

Prognosis

Results are excellent with appropriate treatment.
~90% of patients achieve full or near-full ROM and full or near-full return of preinjury strength (2).

Complications

Extensor lag
Extension weakness
Tendon rerupture

Patient Monitoring

Patients are followed at 1-month intervals until they attain full ROM and strength, and normal gait and function.

References

1. Scuderi C. Ruptures of the quadriceps tendon: study of twenty tendon ruptures. Am J Surg 1958;95:626–634; discussion 634–635.

2. Ilan DI, Tejwani N, Keschner M, et al. Quadriceps tendon rupture. J Am Acad Orthop Surg 2003;11:192–200.

Additional Reading

Dobbs
RE, Hanssen AD, Lewallen DG, et al. Quadriceps tendon rupture after
total knee arthroplasty. Prevalence, complications, and outcomes. J Bone Joint Surg 2005;87A:37–45.

Miscellaneous

Codes

ICD9-CM

844.8 Quadriceps tendon rupture

Patient Teaching

Chronic quadriceps tendinitis should not be ignored because it puts the tendon at risk for rupture with a sudden misstep.
After surgical repair, patients can recover full motion, strength, and function with an intensive physical therapy program.

FAQ

Q: Is quadriceps tendon rupture the only mechanism for losing the ability to extend a flexed knee?

A:
The extensor mechanism includes the quadriceps muscles, quadriceps
tendon, patella, and patellar tendon. All are required to extend the
knee forcefully or to perform a straight-leg raise. A rupture of the
quadriceps or patellar tendon or a fracture of the patella will make
extending the knee difficult.