Regional Pain Syndromes
by Dr. Vinaya Kunjir

Regional musculoskeletal pain such as shoulder, knee, lateral elbow, heel or lateral hip pain is most common form of musculoskeletal complaint.

Regional pain syndromes are conditions that involve pain arising from soft tissue due to some underlying structural pathology and diffuse pain syndromes.

A soft tissue condition consists of disorders of muscle tendons, ligaments, bursae (extensions of muscle tendons which prevent friction of tendons on bony surfaces), joint capsules, fasciae, muscles and peripheral nerve compression.

Cause – Pain is the predominant feature of all soft tissue disorders. The cause of pain may be due to inflammation or degeneration or tear or rupture of the soft tissues. Risk factors of the soft tissue injuries are –

    1.Age - strength of muscles decrease with age and injured tissue take longer time to heal.

    2.Muscle imbalance

    3.Overuse of muscles due to sports

    4.Hyper mobility in joints

    5.Poor blood supply

    6.Estrogen deficiency - in menopause

    7.Diseases - diabetes, inflammatory arthritis

    8.Drugs - can cause soft tissue pains. Eg: steroids, fluoroquiolone antibiotics.

Some Common Regional Pain Syndromes are –

1.Shoulder:-

Shoulder pain is the second most common skeletal complaint in most people.

The shoulder joint has the greatest mobility among all the joints in the body. It is a complex joint composed of 3 bones and 4 joints.

Rotator cuff tendinopathy, caused due to inflammation or injury to the muscle tendons of the shoulder joint.

Adhesive capsulitis – adhesions caused in the joint capsule can lead to decreased movements of the shoulder.

Patient complains of pain in neck and shoulder region, sometimes radiating to elbow. Night pain is common. There is difficulty in lifting the arm above the shoulder or doing overhead work, sometimes associated with 'clicking' sound in the joint. Diagnosis is made by Ultrasound or MRI of the shoulder joint for detecting muscle tears, tendon inflammation or bursitis. Plain X-rays are useful to detect fractures or dislocation of joints.

Treatment consists of :-

    a)Ice – to decrease acute swelling and inflammation.

    b)Rest – avoiding activities which cause pain such as overhead activities.

    c)NSAIDS – a short course of anti-inflammatory analgesics are advised for acute pain.

    d)Exercises – stretching and strengthening of muscles for short term recovery and long term function.

    e)Intra-articular steroid injection – if symptoms do not improve after several weeks of the above treatment, corticosteroid injections in the joint are advised.

    f)Surgery like debridement, acromioplasty or rotator cuff repair is recommended if after 6-9 months of conservative management fail to improve the symptoms.

2.Elbow:-

Lateral epicondylitis is also known as tennis elbow – It is the pain on lateral side of elbow caused by inflammation of muscle tendons due to its overuse. Medial epicondylitis is also known Golfers elbow – painful medial side of elbow caused due to work and sport related overuse of muscles of the elbow. Musculoskeletal Ultrasound is used to detect epicondylitis.

    1.Short term use of NSAIDS.

    2.A compression strap or brace.

    3.Stretching of forearm muscles and exercises at elbow and wrist should be started early.

    4.Local corticosteroid injection can be used for pain relief but is associated with recurrent pain.

    5.Most patients of epicondylitis recover within 1 year.

3.Wrist Joint:-

The wrist joint is formed by the two bones of the forearm and 8 small carpal bones.

1)De Quervain's tenosynovitis -
            Overuse of the thumb by repetitive gripping and grasping leads to friction and irritation of its muscle tendon which progresses to inflammation of tendon.
            Patients complain of pain at the base of thumb and wrist during thumb movements.
            Treatment includes ice applications and NSAIDS to reduce pain and inflammation. Splints.

2)Finger tenosynovitis or Trigger Finger :-
            This condition consists of irritation and inflammation of the Muscle tendons of fingers leading to formation of nodules which cause the fingers to lock while making and opening the fist. Treatment is pain relief, stretching exercises and corticosteroid injections or open surgical release of muscle.

3)Carpal Tunnel Syndrome :-
            Repeated flexion and extension at the wrist joint due to occupational overuse or sports, causes compression on the median nerve at the wrist joint. This causes pain and tingling numbness of the thumb, index finger, middle and half of ring finger. Sometimes, it causes muscle weakness in the hand.

4.Hip :- Greater Trochanteric Pain Syndrome(GTPS)-This presents as dull aching pain on the lateral aspect of hip.  Usually seen in middle aged women history of low back pain and sometimes pain in lateral hip. Pain becomes worse on walking, climbing or running.

GPTS is also called as trochanteric bursitis or hip periarthritis  caused due to inflammation wear and tear of the muscle tendons of the hip joint with or without bursitis. Risk factors are:

    1.Altered lower leg biomechanics.

    2.Obesity.

    3.Hip osteoarthritis.
    
    4.Low back pain.

Diagnosis is made by ultrasound imaging and MRI scans.

Treatment –

    1.Weight loss in obese patients.

    2.NSAIDS for pain relief.

    3.Muscle strengthening exercises for hip and low back.

    4.Local corticosteroids.

    5.Surgery – arthroscopic bursectomy or tendon tear repair for patients unresponsive to medical treatment.

5.Knee:-

The knee joint is formed by the femoral bone of the thigh and tibial bone of the leg. A triangular bone called the Patella protects the knee joint from the front side.

The Iliotibial band is a broad muscle which stabilizes the knee from the front and sideways, while the patellar tendon stabilizes the knee from the front. The iliotibial band and the patellar tendon are prone to soft tissue injuries.

Risk factors are:-

    1.Improper footwear

    2.Sporting events

    3.Knee or hip osteoarthritis

Jumpers knee or patellar tendon rupture is usually seen in young athletes as a result of repetitive trauma and rupture of the patellar tendon. There is pain around knee joint and inability to walk. Iliotibial band friction syndrome (ILTS) is pain and tenderness on (outer) lateral side of knee caused due to friction of distal end of thigh bone and iliotibial muscle during repeated knee movements.

Treatment :- consists of NASAIDS, local corticosteroid injections and muscle strengthening of the knee.

6.Achilles Tendon:-

The Achilles tendon is the largest and the strongest tendon in the human body. The two muscles of the calf combine to form the strong Achilles tendon which gets attached to the calcaneal bone on the back of the foot.
Acute trauma, overuse injuries in sports or occupational overuse or certain drugs can cause inflammation or degeneration or rupture of this tendon - Achilles tendonitis or bursitis and enthesitis. The patient presents with pain- the early morning start up pain and difficulty to walk especially in the mornings. Musculoskeletal Ultrasound is helpful to make the diagnosis.

Treatment is PRICES Approach.

P - Protect the painful region. Do not stress the tendon. Use topical analgesics.
R - Rest the inflammed tendon. Do not overload it.
I - Ice compresses to reduce pain and swelling.
C - Compression.
E - Elevation.
S - Support.

7.Complex regional pair Syndromes (CRPS)-

This consists of continues soft tissue pain, wherein the pain is excessive and disproportionate to the stimulus the touch can cause excessive pain to the patient. The overlying skin can become swollen and show colour changes. The patient feels excessively warm or suddenly cold.

Treatment consists of NSAIDS for pain relief, relative rest fall by gradual stretching and strengthening exercises for the muscles.

Thus pain is the most frequent reason for doctor's consultation in the general population. At least 50% of the patients suffer non-articular rheumatic pain syndromes which results in significant disability and has a major impact on quality of life.

The best strategy is to use a multi disciplinary approach with pharmacological and non-pharmacological treatment.
Non-pharmacological treatment includes exercises, dietary changes, behavioral therapy patient councelling and patient education.

This will help the patient to reduce their symptoms and hence improve their quality of life.