Patellar Tendinopathy

Current Concepts in Patellar Tendinopathy

Abstract
» Approximately 1 in 3 high-impact athletes develops patellar tendinopathy (PT), with the proximal insertion of the patellar tendon being the M.C affected anatomical site.
» Nonoperative treatment options are effective in reducing pain and restoring functionality in most patients with PT.
However, operative intervention should be considered when conservative management fails.
» Both open surgery and arthroscopic surgery for PT have demonstrated favorable success rates and return-to-sport outcomes, with arthroscopic treatment potentially expediting the recovery process.
• Also known as JUMPER’S KNEE

ETIOLOGY-Multifactorial
• chronic, repeated stress to the posterior fibers of the tendon, particularly near the inferior pole of the patella.
• increased stress-drives fibroblasts -stimulate prostaglandin E2 and leukotriene B4- lead to tendinopathy

INTRINSIC FACTORS
• laxity, weight, strength and flexibility of the quadriceps and hamstrings,
• Abnormal arch height of the foot.
• leg length difference,
• waist-to-hip ratio,
• vertical jump performance

EXTRINSIC FACTORS
• Excessive training volume and frequency,
• environmental conditions such as irregularities on the ground,
• inappropriate footwear choices
Histology
• Absence of inflammatory cells. !
Instead,
• neovascular proliferative changes
• hypercellularity with atypical fibroblasts resulting in abnormal collagen distribution

Symptoms
• pain at the proximal insertion of the patellar tendon during athletic activities
• less frequently at the tibial insertion.
• Pain is typical triggered by running, jumping, crouching,

duration of symptoms
• acute (less than 6 weeks),
• subacute (6 to 12 weeks),
• chronic (more than 3 months).

Diagnosis and evaluation
• accurately pinpoint the location of pain

Basset sign
• “passive extension—flexion sign”
• patient is lying down
• palpating the anterior aspect of the fully extended knee
• identifying the tender point (typically at the inferior pole of the patella and proximal part of the patellar tendon)
• A positive test is indicated by reduced tenderness on palpation as the knee is flexed to 90°

Standing Active Quadriceps Sign
• the patient is standing on both extremities
• palpating the entire patellar tendon
• repeat the test with the patient standing only on the affected extremity with 30° of knee flexion.
• If pain significantly lessens in the latter position, the test is considered positive.

INVESTIGATIONS
• Radiographs- overall view of the joint , rule out significant bony involvement or concomitant disorders

Ultrasound
• provides detailed visualization of the tendon
• focal tendon thickening, hypoechogenicity, increased extracellular fluid

MRI
• intrasubstance edema in the tendon
• In chronic cases-reveal cortical irregularities affecting the inferior patellar pole

Blazina Classification
• I -Pain after sports activity
• II -Pain at the beginning of activity, disappearing after warming up, and reappearing at the end of the activity
• III -Pain during and after activity with the patient being unable to participate in sports
• IV -Complete tendon rupture

TREATMENT–

Conservative Management
• Eccentric and isometric exercises (45 min )
• patellar strapping (2 hours)
• sports taping (2 hours)
• platelet-rich plasma (PRP) injections- optimal infiltration site -intratendinous.
• autologous whole-blood injections
• dry needling
• Steroid injections-not advised;potential risk of tendon rupture
• Emerging therapeutive alternatives–Ultrasound-guided percutaneous needle tenotomy (PNT) with a well-structured rehabilitation program

SURGICAL OPTIONS

Open Surgery

making a 5-cm longitudinal incision on the midline of the patellar tendon,
carefully dissecting the paratenon,
Performing a posterior central tenotomy to expose the deepest layers of the tendon
complete the debridement,
drilling multiple holes in the inferior pole of the patella
Direct suture of the tendon.

Arthroscopic Surgery

• introduced by Johnson,
• excision of 25% to 30% -nonarticular portion of the inferior patellar pole – a 4.5-mm spherical arthroscopic burr.

• both open and arthroscopic surgical approaches- favorable success rates .
• arthroscopic treatment may lead to faster Return to sports..
the use of ultrasound guidance with Doppler during arthroscopic surgery -valuable resource

RECENT DEVOLOPMENT-collagen-based bioinductive patch and a PRP membrane in addition to an intratendinous leukocyte-rich PRP injection.