A brace is defined as an orthopaedic appliance or apparatus used to support, align, prevent, or correct deformities or to improve the function of movable parts of the body.
Classification of braces
According to the American Academy of Orthopaedic Surgeons (AAOS), knee braces fit into several categories:
- prophylactic or protective bracing: These are braces intended to prevent or reduce the severity of knee injuries in contact sports
- functional Bracing: braces designed to provide stability for unstable knees or following fractures
- rehabilitative bracing: braces designed to allow protected and controlled motion during the rehabilitation of injured knees
- patello-femoral bracing: braces designed to improve patellar tracking and relieve anterior knee pain.
Indications for bracing
Prophylactic knee braces These have protective function and are pre-emptive braces. They are primarily used for:
- MCL protection against valgus knee stresses in previously unstable knees
- Re-injury protection after previous MCL injury
- Sportsmen at risk for MCL injury
Functional knee braces.
These are primarily designed for:
- reducing translation and rotation following ACL injury
- Additional support after ACL surgery
- support for mild to moderate PCL or MCL instability
- following periarticular stable fractures around the knee joint
Patello-femoral knee braces.
These are designed for :
- patients with patellar subluxation and/or dislocation
- Patellar tendonitis
- chondromalacia of the patella
- Postsurgical for patellar or quadriceps realignment surgery
Apart from specific indication there are many general indications for prescribing braces. Some of the common indications are:
- Documented anterior or posterior cruciate ligament (ACL or PCL) tears or functional instability episodes due to cruciate ligament insufficiency when non-surgical treatment is elected
- Grade II or III medial collateral or lateral collateral ligament sprain to support ambulation when the use of a hinged brace allows for controlled joint motion
- Posterior cruciate or postero-lateral corner reconstruction, including reconstruction after knee dislocation
- Recent surgery for ACL repair in the post-operative recovery phase
- Recent surgery for meniscal cartilage repair in the post-operative recovery phase
- Major ligament and bony reconstruction above the knee such as patella or quadriceps tendon repair, medial and lateral collateral ligament repair
- Major fractures requiring early post-injury or post- operative motion such as patella fractures or tibial plateau fractures
- Osteoarthritis of the knee (unicompartmental) who fulfil any of the criteria as outlined below: (1) High tibial osteotomy or total knee arthroplasty (TKA) (replacement) candidate that may elect non-surgical treatment (2)To predict the success of high tibial osteotomy (3) Severe patellofemoral arthrosis in conjunction with medial or lateral early osteoarthritis
Contra-indications for bracing
There are NO absolute contra-indications to bracing.The use of bracing to achieve rotational control in an ACL deficient knee is a relative contra-indication for bracing. Complicated multi-directional knee injuries such as postero-lateral corner injuries are best treated with surgery with more favourable outcomes. Knee disorders unrelated to the patellofemoral joint or translational instability require surgical management. Complications of Bracing
- Injuries increased by excessive preloading of MCL
- Limited speed and flexibility
- False sense of security for previously injured knee
- Brace-related contact injuries to other players
- Reported effects on translation and rotation disappear at physiologic levels of use
- Increased energy expenditure and clumsiness with decreased agility
- False sense of confidence following ACL reconstruction
- Subjective benefits frequently exceed objective findings
- Increased skin irritation and lesions
- Relatively insignificant pain relief with regular brace wear
- Less effective than conservative therapy (simple stretching and strengthening)
“The important things to consider any time you have a patient being splinted into immobility are the detrimental changes that can occur” (Edward W. Bezkor, Clinical specialist for outpatient physical therapy, NYU Medical Center) According to his research findings corroborated with research nto musculoskeletal changes after bracing reveal fibrotic changes in the tissues and fascial thickening. At the ultramicroscopic level there is the loss of sarcomeres, the contractile unit of muscle fiber most apparent when the muscle is held in a shortened range. This is accompanied by degeneration of the cartilage, because there will not be the healthy stresses placed on the cartilage and the abnormal or limited motion of synovial fluid.
Fabrication / Materials
Knee braces may be custom made or available off-the-shelf in a variety of sizes. Knee braces may be intended for rehabilitation, to reduce pain, or to prevent injury in either stable or unstable knees. Knee braces typically consist of 3 components: a superstructure (usually a rigid shell), a hinge, and a strap system. The superstructure extends proximally and distally to a hinge centered around the knee axis of motion. The strapping system secures the brace to the limb.
Benefits and Limitations of bracing
Since the widespread use of prophylactic braces, several international studies have been carried out to establish if bracing reliably and predictably prevent knee injuries. In most studies there has been serious deficiencies with inadequate control groups, subjective biases, variable rules of different sport, alternative treatment options and regional variations and preferences for ACL / MCL injuries and poor and biased methods of data collection. Thus the outcomes do not lend well to adequate comparison among most studies of prophylactic knee braces. Though some research has shown that that prophylactic knee braces significantly reduce MCL injuries, others have shown very little or no benefit at all even with regular use. As with many types of athletic braces, reported subjective benefits often exalted by inventors or manufacturing companies often exceed objective findings. Patients have also noted significant differences in proprioception between the braced and unbraced extremity. At best, prophylactic knee braces may offer some resistance to lateral knee impact and provide some protection against rotational stresses. It is eminently possible that with ill-fitting or ill-prescribed braces may generate increased forces that compound the original insults to the joint.
Current articles regarding the benefits or otherwise of bracing
1. In vitro assessment of prophylactic knee brace function. France EP, Paulos LE. Clin Sports Med. 1990 Oct;9(4):823-41. Department of Bioengineering, University of Utah, Salt Lake City.
In an attempt to evaluate the effectiveness of prophylactic knee bracing and to determine the influence of brace design and material characteristics on the protection of knee ligaments, a series of biomechanical studies were completed. The first series of tests were preliminary parametric tests of brace function utilising cadaver limbs to understand the failure biomechanics of the medial restraints during low- and high-rate valgus-producing knee trauma. Static and dynamic mechanical properties of the braces were also studied. Finally, a limited series of brace/cadaver knee low-rate loading response tests were performed. The majority of prophylactic knee braces tested p