Q-Angle of the Knee

A well-functioning knee joint is important for mobility. The knee must be able to support the weight of the body during activities such as walking or running.

What is a Q-angle? knee anatomy

The Q Angle, or quadriceps angle, is the angle between the quadriceps tendon and the patellar tendon. An increased Q-angle is a risk factor for patellar subluxation.

How do you measure the Q-angle?

First, you will need to find the patella and its border. Then, you will need to find the center of the patella. You will then need to find the tibial tubercle and draw a line from the ASIS to the center of the patella and a second line from the tibial tubercle through the center of the patella.

normal qThe Q-angle is formed in the frontal plane by the two line segments. It is the angle formed by a line drawn from the Anterior Superior Iliac Spine (ASIS) to the center of the patella. A second line is drawn from the center of the patella to the tibial tubercle. The angle formed by the two lines is called the Q-angle. The normal Q-angle is variable. In males, the angle is usually 14° and 17° in females. A wider pelvis and an increased Q-angle in females is linked to knee pain, patellofemoral pain, and ACL injury. The alignment of the patellofemoral joint is effected by the patellar tendon length and the Q-angle. It is best to measure the Q-angle with the knee in extension as well as flexion.increased q

A larger Q-angle plus a strong quadriceps contraction can dislocate the patella. The Q-angle is increased by:

  • Genu valgum
  • External tibial torsion
  • Femoral anteversion
  • Lateral positioned tibial tuberosity
  • Tight lateral retinaculum

A CT scan study of the patellofemoral articulation is found to be very helpful.

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Bilateral Proximal Biceps Tendon Rupture

Bilateral proximal biceps tendon ruptures are rare. The majority of biceps tendon ruptures involve the long head of the biceps and occurs proximally. When the tendon ruptures, the biceps muscle bunches tendonup in the distal portion of the arm. Ruptures cause a “Popeye muscle” appearance. Both proximal heads of the biceps muscle arise from the scapula. The short head of the biceps originates from the coracoid process. The long head of the biceps originates from the supraglenoid tubercle just above the shoulder joint. Rupture of the long head of the biceps tendon occurs at the bicipital groove and the muscle thebicepsn moves towards the elbow (popeye muscle). The short head of the biceps remains attached to the coracoid. Usually, there is less disability with the proximal biceps tendon rupture than the distal biceps tendon rupture.

The patient may experience cramping, pain, and cosmetic problems with proximal biceps tendon ruptures. The physician may need to perform a surgical procedure called tenodesis of the biceps tendon especially if there is an associated rotator cuff tendon pathology.

 

The Accessory Navicular Bone

What is an accessory Navicular Bone?

accessoryAn Accessory Navicular Bone is an extra bone that may be attached or detached from the navicular bone. It is considered a normal variant and is present in approximately 10% of people. This accessory bone is usually located under the plantar medial aspect of the navicular and is often associated with a pes planus (flatfoot) deformity. Ossification of the navicular bone occurs at three years of age in females and five years of age in males. However, the accessory navicular bone does not begin ossification before eight years of age.

flatfoot

The majority of patients are asymptomatic but, females tend to be more symptomatic. The patient may present with an activity related limp and pain in the arch area. The condition may also be bilateral. During examination, there may be swelling, tenderness, warmth, or redness in the plantar medial aspect of the arch. Relative to a normal foot, a plain x-ray AP view can detect the accessory navicular. An external oblique view is considered to be the best imaging position to detect an accessory navicular bone. An MRI may also be obtained in order to determine the size and type of the accessory navicular as well as assess the posterior tibial tendon.

radiologyThe accessory navicular is classified into three types. In Type I classifications, the accessory ossicle is mainly in the substance of the posterior tibial tendon and is not attached to the navicular. In Type II, the accessory bone resides very close to the navicular tubercle and is connected to the navicular by a thick layer of cartilage. In Type III classifications, the accessory bone is considered an enlarged navicular tubercle. Type IIIs are essentially a type II that is fused with the navicular by a bony bridge.

accessory typesIn regards to prognosis, when skeletal maturity has been reached, almost all patients become asymptomatic.

Treatment

Nonoperative treatment usually consists of activity modification, orthotics, or a short leg walking cast. Surgical excision is indicated only after all conservative treatment options have failed.

 

 

Differential Diagnosis of SI Joint Pain

Sacroiliac Joint pain can often be inappropriately treated or mistaken as lower back pain. There are several conditions that simulate sacroiliac joint pain.

1. Myofascial Painmyofacial pain

This is a chronic pain caused by multiple trigger points and fascial constrictions. This particular condition involves the muscles and fascial areas of the back. The patient may feel knots or hardening of the muscle with weakness and tenderness. Myofascial pain syndrome and fibromyalgia may present the same clinical picture but, they are different problems. The site location is close to the SI joint and can be confused with SI joint pain.

2. Trochanteric Bursitis

Inflammation of the greater trochanter bursa. This condition causes tenderness and pain bursapiriin the hip. Trochanteric bursitis occurs in middle aged women. The area of pain may overlap with the SI joint area of pain and can radiate close to the sacroiliac joint. The pain from this condition is sometimes severe and associated with iliotibial band syndrome. Trochanteric Bursitis is occasionally overlooked. This condition may present with arthritis of the hip and low back pain and other conditions.

 

3. Piriformis Syndrome

This condition occurs when the sciatic nerve is compressed by the piriformis muscle in the buttocks. Piriformis Syndrome may be associated with lower lumbar radiculopathy similar to spine pathology. It occasionally develops due to blunt trauma to the buttocks. Localized buttocks pain will increase with sitting or driving. Tenderness is commonly found in the sciatic notch.

piriformis

4. Cluneal Nerve Entrapment

cluneal nerve entrapThe superior cluneal nerve has three branches. The medial branch of this nerve is confined within a tunnel which may cause impingement of the nerve producing pain close to the SI joint.

5. Lumbosacral Disc Herniation or Bulge

The disc may move out of place (herniate) or break open (rupture) from injury or strain. Disc herniation of the lumbosacral region could involve the nerve roots, creating lower back pain. The pain is usually found in the midline and can go down the leg.

discherniation

6. Lumbosacral Facet Syndrome

facetThe facet provides stability for the spine and contain a joint. This joint may be affected by inflammations or degeneration which causes pain that can be mistaken for SI joint pain.

 

7. Lumbar Radiculopathy

Lumbar Radiculopathy is a major source of back pain. This condition occurs from inflammation, irritation, or impingement of the nerve root. It is commonly confused for SI joint pain.lumbarradi