Structure of the knee

The knee joint is a weight-bearing joint and it functions to allow movement of the leg and is critical to normal walking. The knee joint has three parts.

1.  The bones—Femur of the thigh connected with the tibia of the lower leg to form a main joint. Each protrusion of the lower end of the femur contact to the tibia to form two joints.  The patella (kneecap) stay in front of the joint joins the femur to form the third patellofemoral joint.

2.  The ligaments—The joint is surrounded by a joint capsule with ligaments strapping inside (medial collateral ligament) and outside (lateral collateral ligament) the joint. Two other ligament strapped within the joint firmly attached to the femur on one end and the tibia on the other (anterior and posterior cruciate ligament). The function of the ligaments are to provide stability and strength to the knee joint.

3.  The meniscus--  The meniscus is a thickened cartilage pad between the two joints formed by the femur and tibia. The maniscus functions as a smooth platform for the joint to move on. Bursae are fluid-filled sacs sit around the joint which serve as gliding surfaces that reduce friction of the tendons.

The quadriceps muscle located in front of the thigh extends the knee joint. The knee normally has a 0 degree of extension. The hamstring muscle located in the back of the thigh flex the knee. Normally the knee joint flexes to a maximum of 135 degrees.

 

Causes of knee pain

1)   Trauma.  The knee joint is an active weight-bearing joint and the complexity of the design are factors in making the knee one of the most commonly injured joints.

l        Fracture—Breakage of any of the three bones of the knee joint can occurred during major trauma, such as motor vehicle accidents an impact trauma.

l        Meniscus tears—The meniscus can be torn during sharp, rapid motions. This is common in sports requiring reaction body movements. With aging and degeneration of the cartilage creates higher incidence of tearing. It is often associated with locking or unstable sensation in the knee joint. Sometimes, inflammation or swelling is associated.

l        Ligament injury—One of more ligaments can be injured in a single traumatic event. Local pain on the area of individual ligament involved. Pain, swollen and warm can be experienced. Pain is usually at rest and worsened by bending, weight bearing or walking.

2)   Inflammation.

l        Arthritis—Rheumatoid arthritis or gout arthritis are inflammatory types of arthritis. Ostoarthritis is due to degeneration of the cartilage and it is a type of non-inflammatory arthritis.

l        Tendinitis—Tendinitis is an inflammation of the tendon of muscle which is often produced by a strain, such as jumping.

l        Brusitis—Brusitis commonly occurs on the inside of the knee and the front of the kneecap.

3)   Infection.  Infection of the bone or joint commonly is associated with fever, chill, or warm of the joint. Infection of the joint can rarely be a serious cause of pain.

 

Management of Knee pain

For acute trauma the principle of treatment is the same as any sport injury that is RICE, rest, ice packing, compression and elevation. Analgesic might be used for pain. For infection especially accompanied with open wound, antibiotics might be prescripted.

 

The role of acupuncture in knee pain therapy

l        Acute conditions—The treatment of fracture of bone, rupture of meniscus or complete tear of ligament many time surgery is the only immediately procedure to do.

l        Subacute stage – Pain or swelling of knee joint after trauma acupuncture will be help to relieve pain and swelling to improve the knee function. Fluid accumulation due to trauma or post-operation, clinical experiences demonstrated electo-acupuncture provides a very good result.

l        Chronic pain -- According to National Institution of Health, more than 4 million people seek medical care for a knee problem each year. Patellofemoral pain syndrome (PFPS) is one leading cause of chronic knee pain. PFPS occurs particularly in young adults who participate in sports and is one of the most common diagnosis given at orthopedic centers and sports medicine clinics worldwide.  No single therapy, as to date, has been shown to be completely effective in treating PFPS. Acupuncture, however, has shown promising result on knee pain treatment and may be it is an alternative treatment for patients suffering from PFPS.

 

Literature review   

 

Jensen R, Gothesen O, Liseth K, Baerheim A.

Acupuncture treatment of patellofemoral pain syndrome.

J Altern Complement Med Dec. 1999;5(6):52d1-7

Jensen Fysikalske Institute in Bergen, Norway

 

Objective: To evaluate the effectiveness of acupuncture on PFPS.

Patients: 70 patients from age 18 to 45 randomized assigned into an acupuncture group or a control group. The control group contained 34 patient with 21 female, average age of 33.4. The acupuncture group contained 36 patient with 20 female, average age of 29.

Intervention: All patients in the acupuncture group received needling treatment at the ST-36 and SP-10 acupoints. Several other points also used depending on each patient’s diagnosis. Treatment was rendered by a licensed acupuncturist twice a week for 4 weeks, with each session lasting 20 to 25 minutes. No placebo group was used in this study.

Measurement: Patients were evaluated both before and after treatment using the Cincinnati Knee Rating System (CRS). The CRS measures symptoms of pain, swelling, and function on a scale of 1-100. With a higher score meaning fewer signs of injury or pain.

Result: Within 6 weeks, the CRS scores for patients in the acupuncture group improved 4.2 on pain, 5.1 on function and 6.5 on symptoms. Improvement demonstrated in the acupuncture group continued in the 5-month and has higher score than the control group. The measurements of the 12-month showed the CRS scores (in compare with the baseline) for patients in the acupuncture group improved 6 on pain (control group 1.9), 6.8 on function (control 1.9) and 10.3 on symptoms (control 3.7). A different of CRS, Global score for acupuncture treated patients is 17.2 which is far beyond the score for control group 5.6.

Conclusion: This study is one of the largest treatment studies on the PFPS, and it shows a clear, durable effect of acupuncture treatment in reducing pain and improving function for the patient.

 

Christensen BV, Juhl IU, Wilbek HH, Dreijer NC, Rasmussen HF

Acupuncture treatment of knee arthrosis. A long-term study

Ugeslr Laeger 1993 Dec 6:155(49):4007-11

Denmark

 

OBJECTIVE: To examine acupuncture treatment of patients with ostoarthrosis of the knee.

PATIENT: 29 patients with a total 42 osteoarthritic knees were randomized to two groups.

INTERVENTION: Group A was treated with acupuncture while group served as a no treatment control group for nine weeks. In the second part of the study 17 patients (26 knees) continued with treatment once a month for a total period of 49 weeks.   

MEASUREMENT: Analgesic consumption, pain and objective measurements were registered from both groups for comparison.

RESULTS: There was a significant reduction in pain, analgesic consumption and in most objective measures. The range of movement of the knee demonstrated a significant increasing.

CONCLUSION: The results of this study were significantly better in those who had not been ill for a long time. The second part of the study showed that it was possible to maintain the improvement.

 

Abhay Tillu, Sumedha Tillu, Sarah Vowler

Effect of acupuncture on knee function in advanced osteroarthritis of the knee: a prospective, non-randomized controlled study

Acupuncture in Medicine 2002:20(1):19-21

Orthopaedics Department, Bedford Hospital, Bedford

 

OBJECTIVE: Osteoarthritis is a second only to cardiovascular diseases in producing chronic disability. As life expectancy rises, there are more patients being referred with advanced osteoarthitis of the knee. For many the treatment of choice is total knee replacement. Of those considered, some may be unfit for major surgery, and those are fit inevitably spend months on a waiting list, or consume a great amount of resource. Acupuncture has been shown to be effective in relieving pain in advanced cases of osteoarthritis of knee, this prospective control trial, comparing acupuncture with no treatment to evaluate the effectiveness of acupuncture in patients with advanced osteoarthritis  of knee awaiting total knee replacement.

PATIENT: 75 consecutive patients on the waiting list for a total knee replacement were contacted and asked to participate in the study. Patients who received arthroscopic washout within 6 months, intra-articular steroid injection to the knee within 3 months, acupuncture treatment within one year and inflammatory arthritis were excluded from this study.

INTERVENTION: 37 consecutive patients were allocated to group A receiving acupuncture treatment and next 38 patients to group B receiving no treatment. Four local points around the knee and one distal point use for needling. All the needles stimulated 4 times during 15 minutes of treatment. All patients received acupuncture treatment at weekly intervals for 6 weeks.

MEASUREMENTS: Baseline knee function of all patients was assesed by one of the authors (ST) prior to commencing treatment, using the Hospital for Special Surgery (HSS) knee score, time taken to walk 50 meters, time taken to climb 20 steps, and a visual analogue pain score (VAS).

RESULTS: 60 patients were successfully completed the trial, 30 in the treatment group (female 60%, average age of 73.6) and another 30 in the control group (55% female, average age of 74.6). The results of the parameters were: HSS (group A) from 60.0 (before treatment) increased to 70.0 (p<0.001) (group B: 54.5 to 53.5, p=0.03); walk (group A) from 41.0 to 35.5 (p=0.02) (group B: 43.0 to 45.5, p<0.01); climb (group A) 26.5 to 21.0 (p=0.02)(group B: 31.5 to33.5, p=0.002); and pain (group A) 5.1 to 3.1 (p=0.002) (group B: 5.7 to 6.0, p=0.01). In the acupuncture group at two months follow up, the time to walk 50 meters, climb 20 steps, and the pain scores, fell and the HSS scores increased. The converse was found in the control group. Symptoms in three patients in the acupuncture group improved to the extent that they requested suspension from the waiting list of knee joint replacement. 

CONCLUSION: This trial demonstrated the acupuncture treatment group improved in all parameters, whereas the control group deteriorated, a finding that was highly statistically significant (p<0.0002).