Editors: Frassica, Frank J.; Sponseller, Paul D.; Wilckens, John H.
Title: 5-Minute Orthopaedic Consult, 2nd Edition
Copyright ©2007 Lippincott Williams & Wilkins
> Table of Contents > Patellar Tendon Rupture
Patellar Tendon Rupture
John H. Wilckens MD
Jamil Jacobs-El MD
BasicsDescription
Patellar tendon rupture is a disruption of the segment
of the extensor mechanism extending from the inferior aspect of the
patella to the tibial tubercle.
of the extensor mechanism extending from the inferior aspect of the
patella to the tibial tubercle.
Epidemiology
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Patients usually <40 years old
-
Affects males more than females
Risk Factors
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History of patellar tendinitis
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Steroid injections around the patellar tendon
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Dialysis
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Anabolic steroid use
-
Corticosteroid use
Etiology
Ruptures usually result from trauma in which a violent
quadriceps muscle contraction occurs against resistance in the flexed
knee.
quadriceps muscle contraction occurs against resistance in the flexed
knee.
DiagnosisSigns and Symptoms
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Defect in the patellar tendon
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Inability to extend the knee from the flexed position
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Injured patella resting more proximally than the uninjured knee and migrating proximally with active quadriceps contraction
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Acute injuries usually are associated with substantial knee effusion and pain on active or passive ROM.
Physical Exam
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Check for pain or swelling in the affected knee.
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Patient is unable to perform a straight-leg raise.
-
Perform an active knee extension test to identify loss of integrity to the extensor mechanism.
-
Palpate for a defect in the patellar tendon.
Tests
Imaging
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Radiography:
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Obtain plain AP and lateral radiographs of the knee to rule out patellar fracture and tibial plateau fractures.
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Usually, the patella has migrated proximally.
-
-
-
MRI is diagnostic.
Pathological Findings
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Complete rupture of the patellar tendon with degenerative changes noted in the tendon (1)
-
The patellar tendon may avulse from the
inferior pole of the patella or from the tibial tubercle, or it may
sustain an intrasubstance rupture.
Differential Diagnosis
-
Extensor mechanism injuries (2):
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Quadriceps tendon rupture
-
Patellar dislocation
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Patellar fracture
-
-
Intra-articular disorders:
-
Ligament tears
-
Occult tibial plateau fractures
-
With the previously listed 2 disorders, extensor mechanism function may shut down with a large effusion.
-
TreatmentGeneral Measures
-
Patellar tendon ruptures require operative repair.
-
Patients with acute ruptures should be
placed in a knee immobilizer for comfort and referred to an
orthopaedist for surgical treatment. -
Patients may bear weight as tolerated as long as the knee is locked in extension.
Special Therapy
Physical Therapy
-
Patients may require physical therapy for quadriceps strengthening and ROM exercises.
-
Begin with straight-leg raises and quadriceps sets.
-
Allow early ROM within the limits of tension of surgical repair.
-
May bear weight as tolerated with the knee locked in extension
-
-
Core strengthening:
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After 6 weeks, advanced ROM and strength training as tolerated
P.313
Medication
Analgesics can be given for pain management acutely and after surgery.
Surgery
-
Acute ruptures must be repaired surgically.
-
Early repair allows for maintenance of patellar tendon length and better functional results.
-
Chronic patellar tendon tears usually require some type of reconstructive procedure and/or augmentation (3).
-
Patients usually are treated with an above-the-knee cast or a knee brace locked in extension for ~6 weeks after surgery.
Follow-upPrognosis
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Most patients treated with early patellar tendon repair have good or excellent results.
-
Chronic tendon ruptures are more difficult to repair, but repair provides better results than nonoperative treatment.
Complications
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Knee loss of motion
-
Extensor weakness
Patient Monitoring
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See patients 7–14 days after surgery for removal of stitches.
-
Follow-up every 4–6 weeks until full ROM and strength are achieved.
References
1. Kannus P, Jozsa L. Histopathological changes preceding spontaneous rupture of a tendon. A controlled study of 891 patients. J Bone Joint Surg 1991;73A:1507–1525.
2. Wilckens
JH, Mears SC, Byank RP. Knee, lower leg, and ankle pain. In: Barker LR,
Burton JR, Zieve PD, eds. Principles of Ambulatory Medicine, 7th ed.
Philadelphia: Lippincott Williams & Wilkins, in press, 2006.
JH, Mears SC, Byank RP. Knee, lower leg, and ankle pain. In: Barker LR,
Burton JR, Zieve PD, eds. Principles of Ambulatory Medicine, 7th ed.
Philadelphia: Lippincott Williams & Wilkins, in press, 2006.
3. Matava MJ. Patellar tendon ruptures. J Am Acad Orthop Surg 1996;4:287–296.
MiscellaneousCodes
ICD9-CM
844.8 Patellar tendon rupture
FAQ
Q: How can a quadriceps tendon rupture, a patellar tendon rupture, and a patellar fracture be differentiated?
A:
All 3 result in extensor mechanism weakness and inability to perform a
straight-leg raise. All of them also have a palpable defect. With a
patellar fracture, the proximal fragment is retracted proximally and
the distal fragment is retracted distally, creating a gap between the
fracture fragments. A quadriceps tendon rupture results in the distal
migration of the patella with the defect above the patella. A patellar
tendon rupture results in the proximal migration of the patella and a
defect distal to the patella.
All 3 result in extensor mechanism weakness and inability to perform a
straight-leg raise. All of them also have a palpable defect. With a
patellar fracture, the proximal fragment is retracted proximally and
the distal fragment is retracted distally, creating a gap between the
fracture fragments. A quadriceps tendon rupture results in the distal
migration of the patella with the defect above the patella. A patellar
tendon rupture results in the proximal migration of the patella and a
defect distal to the patella.
Q: Can you rupture a healthy patellar tendon?
A:
Although some patients may not report a prodromal period of patellar
tendinitis, all ruptured patellar tendons reveal evidence of tendon
degeneration. However, it is possible to lacerate a healthy tendon.
Although some patients may not report a prodromal period of patellar
tendinitis, all ruptured patellar tendons reveal evidence of tendon
degeneration. However, it is possible to lacerate a healthy tendon.