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Patellar and Quadriceps Tendon Rupture

Source : Campbell & Rockwood


•Patients with

loss of active knee extension

•as a result of trauma

without signs of a patellar fracture

•may have a disruption of the extensor mechanism.

•Injuries to the extensor mechanism can include

•quadriceps or patellar tendon ruptures,

•patellar dislocations, or tibial tubercle avulsions. Can rule out with the xray


Quadriceps femoris muscle has four parts: rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.

The quadriceps tendon inserts onto the base of the patella. Distal to the patella, it continues as the patellar ligament.

•Patellar Tendon

•Average 4mm thick, but widens to 5-6mm at insertion in to tibial tuberosity

•Merges with Medial & Lateral retinaculum

Blood Supply

•Fat pad vessels supply posterior aspect of tendon via Med. & Lat. Inferior Geniculate A.

•Retinacular vessels supply Anterior portion of tendon via Lat. IG & Recurrent Tibia A.

•Proximal & distal insertion area are relatively avascular and are a common site of rupture


•Greatest force is applied at 60 degree flexion

•3-4 times force at @ insertion as compared to midsubstance

•While climbing stairs forces through patellar tendon is x3.2 times body weight

Mechanism of Injury

•Quadriceps and patellar tendon ruptures are typically low-energy injuries.

•Typically, the patient sustains a forceful quadriceps contractionagainst a fixed or sudden load of full body weight with the knee in a flexed position.

•In high-energy injuries it may accompany ACL tear in 12.5% cases.

Clinical Presentation

Age Group commonly involved

•Patellar tendon ruptures : <40 years old

•quadriceps tendon ruptures : >40 years of age

•Quadriceps tendon ruptures occur more commonly in patients with systemic disease or degenerative changes.

Bilateral quadriceps tendon rupture may occur in patients with systemic illness and obesity. Bilateral rupture of the patellar tendon can occur but is less frequent.

History of jumping,squatting or stumbling.

Pain with an associated tearing or popping sensation is typical, as is the inability to bear weight.

•Painful passive knee flexion

•Lack of active knee extension or the inability to maintain the passively extended knee against gravity

Patellar tendon ruptures extend completely through the retinacular tissue resulting in complete loss of knee extension.

•In Quadriceps tendon ruptures some extension still may be possible as whole retinacular tissue is not involved.

•Immediately after injury, a defect may be palpable at the level of the rupture.

•However, when the diagnosis is delayed, the tendon defect may not be palpable secondary to consolidation of the hematoma and early scar formation.

•A traumatic hemarthrosis is common after extensor mechanism injuries.

•History of Prodromal symptoms: fever, malaise, headache

In general, healthy tendons do not rupture. Tensile overload of the extensor mechanism usually leads to # patella which is considered the weakest link.

•Thus Patellar tendon ruptures have been considered the end stage of long-standing chronic tendon degeneration.

•So Prodromal Symptoms are frequently associated with tendon rupture.

•Complaint of chronic pain is also present at site of the injury.

Risk factor for Quadriceps/Patellar Tendon Rupture



Diabetes –( Patellar Tendon more association)

•Chronic Renal Failure

•Systemic corticosteroid therapy

Anabolic steroid use with Heavy Exercise –( Quadriceps Tendon more association)

•Local steroid injection

•Chronic patellar tendonitis

Fluoroquinolone antibiotics



•An AP and lateral plain radiograph should be obtained in all patients.

Patellar Tendon Rupture :

•The unopposed pull of the quadriceps muscle will result in proximal migration of the patella.

Patella alta- position of the patella is considered higher than normal

•position of the patella superior to Blumensaat's line on the lateral radiograph

Insall-Salvati Index - normal value between 0.8-1.2 . If the ratio is higher than there is patella alta

Blumensaat line

is a line which corresponds to the roof of the intercondylar fossa of the femur as seen on a lateral radiograph of the knee joint.

Blumensaat's line should extend to inferior pole of the patella at 30 degrees of knee flexion

•Xray findings suggestive of a quadriceps tendon rupture include

•obliteration of the quadriceps tendon shadow,

•a suprapatellar mass,

•suprapatellar calcific densities

•an inferiorly displaced patella.


•High-resolution ultrasonography has been recognized as an effective method of examining the patellar and quadriceps tendons in both acute and chronic injuries.

•Routinely done method to confirm diagnosis.

MRI is very effective but expensive, method of diagnosing.

•It is not recommended in the evaluation of most suspected extensor mechanism injuries, but may be helpful in patients with neglected tears or partial tendon injuries or high-energy injury.

Initial Management


•A traumatic hemarthrosis is common after tendon ruptures.

•Ice, compression, elevation, and anti-inflammatory medications can be used to treat local symptoms.

•Role of Knee aspiration

•no studies have shown a benefit for knee aspiration in these injuries,

•aspiration of a tense hematoma WAS considered to reduce pain and promote recovery.

Treatment Options :

Conservative & Operative

Conservative Treatment

•The limb is initially immobilized with the knee in full extension for 4 to 6 weeks,

•after which, protected range of motion and strengthening are begun.

•Initially, flexion of greater than 90 degrees is avoided to reduce stress on the tendon.

•Restrictions are removed once the patient achieves good quadriceps muscle control and is able to perform a straight-leg raise without discomfort.

Outcome of conservative treatment

•Nonsurgical management of a complete quadriceps or patellar tendon rupture generally yields poor results

•long-term disability in gait and weakness.

•Untreated complete ruptures will result in ambulation with a stiff-knee gait or circumduction to allow the foot to clear the ground during the swing phase of gait.

•Patients will also complain of knee buckling and difficulty in climbing stairs.

•And Loss of extensor mechanism function is an indication for surgery.

Operative Treatment

•Operative treatment is indicated for all tendon ruptures in which extensor mechanism function is compromised.

Patient positioning

•Supine positioning

•A small bump under the hip is helpful for external rotation of the limb

•Another small bump that can be

•moved below the knee for slight flexion or

•under the ankle for knee extension

Surgical Approach

•An extensile straight midline incision

•inferior patella to 5 cm proximal to the quadriceps tendon rupture

•superior patella to the tibial tubercle for patellar tendon ruptures.

Acute v/s Chronic Tendon Tear

•In acute cases end-to-end repair is possible

•But in chronic cases there is a large defect preventing apposition of ends

•In quadriceps rupture >2weeks , a gap of 5cm is formed due to muscle retraction.

•Various muscle release or lengthening procedures may be required in chronic cases.


Suture repair through bone tunnel

•Passage of two heavy non-absorbable sutures into the tendon.

•Three parallel drill holes are then created from superior to inferior through the patella.

•The sutures are passed through the drill holes and tied at the inferior patella

•Tensioning of suture to allow 90 to 100 degrees of passive flexion has been recommended.

•The tendon should be repaired adjacent to the articular surface because if sutured to anterior surface it will lead to tilting of the patella.


Codivilla tendon lengthening and repair of quadriceps tendon

•An inverted V is cut through the full thickness of the proximal segment of the quadriceps tendon

•A triangular flap is split into 2 part

•Anterior part of one third of its thickness and

•a posterior part of two thirds.

Anterior part of the flap is turned distally and is sutured.


•The cylinder cast or knee brace for 6 weeks.

•Weight bearing with crutches is allowed at 3 weeks.

•After Cast removal range of knee motion from 0 to 60 degrees; the range is increased 10 to 15 degrees each week.

•An aggressive strengthening program is essential for good functional recovery.


•The site of the tear (proximal, midsubstance, or distal) will dictate the preferred surgical repair technique.

•Most patellar tendon ruptures occur at the insertion on the inferior pole of the patella as an avulsion.

•It is done by passage of 3 heavy non-absorbable sutures into the tendon.

•4 parallel drill holes are then created from inferior to superior in the patella.

•The sutures are passed through the drill holes and tied at the superior pole of the patella.


If the patellar tendon is extensively frayed, 2 running interlocking non-absorbable sutures can be used to secure the tendon.

•Use a suture retriever or Beath pin to thread the suture strands through 3-mm drill tunnels,

one horizontally into the tibial tubercle

two vertically into the patella

*If secure fixation cannot be obtained with this method, augment the repair with the semitendinosus or gracilis tendon.


•The tendon is split in 3 bundles. (2 with long arm directed upwards & 1 downwards)

•Running interlocking sutures placed in bundles

•2 parallel vertical holes drilled in the patella & 1 transverse hole drilled in the tibial tuberosity.

•Sutures are passed through holes & tied.

•Repair the individual bundles side-to-side after appropriate tendon length is determined.

*If needed place a circumferential tension suture of non-absorbable box wire.


For proximal avulsion of the tendon from the patella, place three suture anchors equidistant along the inferior pole of patella.

•Pull the suture through the anchor eyelet Pass the one suture arm down and back of the tendon stump in a locking Krackow fashion, and pull the another arm to reduce the tendon & Tie each suture securely.

For distal avulsion of the tendon, the same procedure is used but the suture anchors are placed in the tibial tubercle

POSTOPERATIVE CARE following repair of acute patellar tendon repair

Weight bearing is allowed with the knee braced in full extension.

Range of Motion is progressed as tolerated, with the goal of

•90 degrees of flexion by 4 to 6 weeks and

•full motion by 10 to 12 weeks.

•Isometric quadriceps contractions can be done immediately after surgery,

•Progressing to straight-leg raises start at 6 weeks.

•Full return to activities after 6 months.


In chronic cases patella is retracted proximally and may require extensive surgical release to draw it distally to the appropriate level.

Before surgery, lateral radiographs of the uninvolved extremity should be

obtained with the knee flexed to 45 degrees to evaluate patellar height;

•These are compared with radiographs of the involved knee during surgery to determine the appropriate tendon length.

•Preoperative traction through a K-wire placed transversely in the patella was used

•But, better results can be obtained with proximal release of scar tissue and a modified Thompson quadricepsplasty, if necessary.

Modified Thompson quadricepsplasty is a Z-plasty lengthening of the rectus femoris tendon


•Use an oscillating saw to make a slot in Tibial tuberosity

•Contour the bone attached to the Achilles tendon to fit flush in the slot

•Split the Achilles tendon graft into three branches, the central branch should be 8 to 9 mm in diameter.

•Central arm of graft is placed through 9 mm longitudinal tunnel and then through vertical slit in quadriceps tendon.

•Tunnel is placed centrally to avoid penetration of articular cartilage.

•Graft is secured with multiple sutures.


•Apply cylindrical cast post-OP. At 10 to 14 days, the cast is removed for wound evaluation.

•A cylinder cast or locked brace is worn for 4 to 6 weeks.

•At 4 to 6 weeks, after removing cast Active and passive range-of-motion exercises are begun.

Weight bearing to tolerance with crutches is allowed until sufficient motion and strength is gained.

•A progressive strengthening and range-of-motion exercise program is essential to regain function.


Technique for one-stage delayed reconstruction of patellar tendon.

A, Steinmann pin through transverse hole in patella is used for distal traction.

B, Proximally divided semitendinosus and gracilis tendons are placed through holes and fixation wire is inserted.

C, With patella in normal position, fixation wire is secured and gracilis and semitendinosus tendons are sutured to each other.


A, Z-shortening of patellar tendon and Z-lengthening of quadriceps tendon.

B, Tack sutures are placed in tendons after confirming patellar height

C&D, a transverse hole in patella is made Semitendinosus and gracilis tendons are harvested with tendon stripper and sutured together.

E, Tendons are passed through transverse hole in patella and sutured together and also to underlying patellar tendon.


•At 2 weeks, the cast is removed for wound evaluation and a new cylinder cast or locked brace is applied.

•At 6 weeks, vigorous straight-leg raising with weights and active flexion exercises are instituted.


•good to excellent results in 80% to 100% of operatively treated quadriceps tendon ruptures

•Many different techniques of primary repair have been described and no single technique has demonstrated superiority.

•The only factor that has been associated with inferior results is delay in timing of surgical repair of greater than 2 to 3 weeks.


•Overall, less satisfactory than repair of an acute tear

•Residual functional deficits present in most patients.

•Some reported good to excellent results in patients treated with their modification of the Codivilla lengthening technique.

•More than half delayed repairs lost between 10 and 20 degrees of full active extension at final follow-up in few studies.


•Most series have reported between 70% and 100% good to excellent results.

•The majority of patients who undergo early primary repair achieve a functional range of motion and normal quadriceps strength.

•Persistent quadriceps muscle atrophy commonly occurs, but has not been correlated with loss of strength.

•No relationship has been demonstrated between the configuration of the rupture, the method of repair, and clinical outcome.

•An early repair within 2 to 3 weeks of injury is the only factor that has been associated with better outcomes.

•In patients treated within 7 days ,96% had good to excellent results.

•Patients with multiple injuries may have contributed to the slightly lower success rate in some series.


•A vey few series recommended preoperative traction to overcome the contracted quadriceps muscle so that the tendon ends could be re-approximated.

Results have generally been less satisfactory compared to acute repair.


Rockwood and Green's Fractures in Adults

Campbell's Operative Orthopaedics

Images : Internet

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