CHAPTER 40 ORTHOPEDIC DISORDERS
Practice of Geriatrics
CHAPTER 40 ORTHOPEDIC DISORDERS
Thomas P. Sculco, M.D.
Trauma and Fracture Management
Management of Arthritis in Geriatric Patients
The impact of musculoskeletal disorders on the geriatric population is immense. It is estimated that by the year 2030, 21% of the United States population will be over the age of 65. Today 30% of all hospitalized individuals are elderly.1 In addition to the medical risks and disabilities produced by musculoskeletal diseases, these conditions may significantly alter the ability of geriatric patients to maintain independent function. This is most commonly seen in elderly patients who fall and fracture a hip. The need for hospitalization and rehabilitation is difficult and frightening for these patients, but just as worrisome is the possible loss of autonomy that may ensue as a result of such injuries. Aside from trauma, osteoporosis and arthritic afflictions are also major causes of functional disability in the elderly leading to loss of independence. The myriad medical diseases that exist concomitantly in this population compound the loss of function from musculoskeletal problems and may be devastating physically and psychologically. Once these conditions weaken the physical well-being of geriatric patients, their will to persevere emotionally weakens, and a downward spiral may begin that can lead to their demise.
Prevention of loss of ambulatory and independent functioning is the cornerstone of musculoskeletal care in the geriatric population. Conditioning and exercise programs to maintain the strength and mobility of joints is vital. Additionally, bone density is best maintained by exercise, which helps to maintain mineral bone by muscle forces acting on bone. Balance dysfunction and poor coordination affect gait and severely affect the elderly. Falls may ensue with fracture or failure to walk because of fear, greatly weakening the muscles necessary to promote ambulation and aggravating osteoporosis.
In this chapter the major orthopedic problems seen in the geriatric patient are reviewed. These include fractures, osteoporosis, and arthritis. An approach to the patient with these conditions, as well as their medical and surgical management, is also described.
TRAUMA AND FRACTURE MANAGEMENT
Fractures occur commonly in geriatric patients for a number of reasons. First, most patients, particularly postmenopausal females, have significant osteopenia. Reduction in bone mineral frequently leads to fractures of the femoral neck, wrist, and spine. Falls in these patients occur because of poor balance and proprioception; vision may also be impaired.2 Even a minor impairment in walking ability can lead to unexpected events, which in weakened bone can produce significant fractures. Additionally, bone may be so compromised in elderly patients that stress fractures in the femoral neck may occur, in fact precipitating a fall rather than the fall leading to a fracture.3 Many elderly people take multiple medications, which may impair balance and lead to injury. Furthermore, particularly at night, episodic confusion may develop, possibly resulting in traumatic injury and fracture.
A common and devastating fracture in the older patient is a fracture of the upper femur. In 1990 there were 1.66 million hip fractures globally, more than half of them in the United States and Europe. This number is expected to rise significantly to 6.26 million in the year 2050.4 Although the term commonly used is hip fracture, these fractures do not actually involve the hip joint itself but are located in either the femoral neck or the intertrochanteric area of the upper femur. Femoral neck fractures are often displaced, the head of the femur being shifted into an inferior position on the neck of the femur and the lower extremity shortened and externally rotated (Fig. 40-1). Intertrochanteric fractures occur through the lesser and greater trochanter and generally do not produce as much shortening or limb rotation.
Figure 40-1 Left femoral neck fracture with displacement of the femur.
Whenever an elderly patient falls and is unable to rise and bear weight on the injured lower limb, a fracture of the upper femur must be suspected. These patients should be made comfortable and should not be moved because further displacement of the fracture may occur. The limb should be splinted, and the patient brought to an emergency room for confirmatory radiographs.
Depending on the location of the fracture, internal fixation, a femoral head replacement, or total hip replacement is needed. In severe fractures of the femoral neck, the shaft of the femur migrates proximally and the femoral neck essentially collapses posteriorly and medially. Because of the tenuous blood supply to the femoral head that enters through the capsule of the hip joint, femoral neck fractures that are displaced can violate this circulation and jeopardize the viability of the femoral head. Reduction in blood flow to the fracture site by this injury can also lead to non-union of these femoral neck fractures even after internal fixation has been performed. For these reasons, subsequent avascular necrosis to the head of the femur and non-union of the fracture may occur in 40% to 50% of patients. Excision of the fractured femoral neck and head and replacement with a prosthetic head is therefore the treatment of choice in these patients5 (Fig. 40-2). If the femoral neck fracture is minimally displaced, the blood supply is generally preserved, and internal fixation with multiple pins may be performed.
Figure 40-2 Left femoral neck fracture treated with femoral neck excision and replacement with a prosthetic femoral head and acetabulum.
Intertrochanteric fractures tend to be more complex and are not easily amenable to replacement. These fractures involve the lesser and greater trochanters and are below the femoral neck. They are generally treated by internal fixation with screw or blade devices that transfix the fracture; plates are incorporated into these devices and are attached to the femoral shaft with multiple screws (Fig. 40-3). Avascular necrosis and non-union are uncommon in intertrochanteric fractures because the fracture is below the neck of the femur and the hip capsule and does not compromise the blood supply to the femoral head.
Figure 40-3 A, Right intertrochanteric femoral fracture. B, Left intertrochanteric femoral fracture treated with an internal fixation device.
The goal of management of intertrochanteric or femoral neck fractures is stabilization of the fracture (or replacement of the involved bone) and early mobilization of the patient. Rapid and aggressive rehabilitation of the patient is crucial if a return to ambulatory status is to be accomplished. Medical problems develop quickly in geriatric patients who cannot be mobilized from bed. Atelectasis, pneumonia, decubitus ulcer, urinary retention, ileus, and confusion are all seen in postoperative geriatric patients after fracture of the upper femur, and these complications can seriously compromise recovery. It is imperative for the orthopedic surgeon to obtain stabilization of the fracture so that the patient can be transferred comfortably from bed, and rehabilitation can begin immediately. Comprehensive geriatric-orthopedic care has been demonstrated to improve outcomes in elderly patients with hip fractures.6,7
Rehabilitation should include ambulation with assistive devices, depending on the strength of the patient. Most patients begin with a walker and advance to a cane when weight-bearing is permitted. When a prosthetic replacement is performed, weight-bearing can begin immediately, and the patient can advance as tolerated. In patients with fractures that have been internally fixed, weight-bearing may be delayed, progressing as healing at the fracture site is demonstrated on radiographs. Generally, these patients remain on a walker for 6 weeks and use a cane or crutches for an additional 6 to 8 weeks. Because of other associated conditions that may influence the patient’s ability to ambulate safely, a cane is often needed outdoors for walking. This practice should be encouraged in patients who have poor balance and are prone to falls. Most patients do return to ambulatory status after a hip fracture although they are not as independent as they were before the fracture. Koval and colleagues reported in a review of 336 patients with hip fractures that by 1 year after hip fracture 41% of patients had regained their prefracture ambulatory ability, 40% remained ambulatory but required assistive devices, 12% regressed from community to household ambulation, and 8% became nonfunctional ambulators.8
Many elderly patients with hip fractures present in a poor nutritional state, which may lead to delayed postoperative wound healing. Wound drainage postoperatively due to fat necrosis of subcutaneous tissue, superficial and deep infection, and wound breakdown are all more common in geriatric patients. Physiologic reserves are lower in geriatric patients, and should a major medical or surgical complication occur, their recovery potential is markedly impaired. In turn, this may lead to a series of additive problems that aggravate and prolong recovery and may in fact become life threatening. Careful proactive medical management and nutritional supplementation is important in these patients.
Aside from the myriad medical complications that can ensue after surgical treatment of fractures of the upper femur, the patient may not be able to return to independent functioning in the home after discharge. A period of time at a rehabilitation center is routinely recommended for these patients, and a home care program is necessary when they are able to return home. Often these patients have been living marginally alone and have adapted their home setting to make it possible to remain independent and fairly self-sufficient. When admission to a hospital is necessary for stabilization of a fracture, the fragile nature of the home situation becomes more problematic. Although many vigorously demand to return to their previous living arrangements, rehabilitation from a hip fracture may be slow and arduous and may reduce their ability to return to their previous accommodations. Most patients fear being sent to a nursing home or institution, but the traumatic event of the musculoskeletal injury has decreased their ambulatory function, and an unsupervised existence is unsafe. This situation may severely affect the patient psychologically, leading to depression, which can compromise rehabilitation efforts.
Aside from fractures involving the hip joint and upper femur, fractures of the pelvis, usually the public rami, occur commonly in the elderly. These fractures may result from trivial trauma, or, in a severely osteoporotic patient, simply rolling over in bed may precipitate a stress fracture of the public rami. The patient complains of groin pain that is exacerbated by walking or rising from a seated position. These fractures tend to be quite stable and heal with no problems. Pain with weight-bearing may persist for 6 to 8 weeks, however, and this severely limits the ability of the patient to be independent. This immobility may lead to a series of complications resulting from bed rest that are often far more life-threatening than the pelvic fracture itself. Treatment is symptomatic, and the patient should be encouraged to ambulate with a walker as soon as he or she is comfortable. Early mobilization from bed is necessary to avoid the systemic complications associated with bed rest. Most pelvic fractures heal within 6 to 8 weeks.
Lower Extremity Fractures
Aside from fractures of the hip, the femoral shaft, knee joint, tibia, and ankle may be fractured in older people. Ambulatory function is immediately curtailed once these injuries occur, and the primary goals of treatment are restoration of fracture stability and return to ambulation. Prolonged periods of immobility produced by these injuries will lead to marked muscle atrophy, joint contracture, and failure to regain the ability to walk. For these reasons, nonsurgical treatment with plaster immobilization and traction methods are employed infrequently. When appropriate, immobilization for management of a fracture is best performed using the newer synthetic bracing materials, which tend to be lighter in weight and are better tolerated in the elderly. These braces can be removed for observation of the skin, which is fragile in the elderly and is prone to breakdown. Impaired sensation can also produce skin ulceration beneath immobilizing devices; if this is undetected, infection may occur that may threaten the viability of the limb. Early discontinuation of immobilization is preferred in the management of all fractures if function is to be recovered.
In addition to problems related to the soft tissues encased beneath a cast, the limb must be constantly observed for swelling, and the patient should be encouraged to elevate to the leg. Plaster, because of its weight, makes transferral from a seated position more difficult and ambulation often impossible, and therefore it is now used infrequently.
Open surgical reduction of the fracture fragments and internal fixation with various newer devices can produce immediate stability of the fracture, allowing early joint mobilization and ambulation. Difficulty with fracture fixation in osteoporotic bone persists as a problem, and this can compromise fracture position and healing. In fractures of the lower limb in which the joint is involved, constant passive motion devices are used to allow early joint motion. Bracing is used to supplement fracture fixation externally when the bone is of poor quality and additional support is needed for fracture healing. Protected weight-bearing with a walker, crutches, or a cane is generally necessary after a fracture of the lower extremity. Crutches are often difficult for geriatric patients to master, and therefore a walker is recommended to improve support and assist balance.
Early return to ambulation is the essential outcome of any fracture of the lower extremity, and management of these fractures must be directed at this end result. Complications of fractures in the elderly include non-union, malalignment after fracture healing, delayed wound healing, and infection. Should any of these problems develop, further surgical intervention is often necessary, leading to increased morbidity.
Upper Extremity Fractures
The concepts of fracture management in the upper extremity are similar to those of lower extremity fractures. The goal is to effect fracture healing and maintain function. Early return of motion is especially important in the upper extremity, and this dictates early removal of immobilization devices and physical therapy for active and passive range of motion and strengthening exercises.
The most common fractures of the upper extremity in the geriatric patient are Colles’ fractures (fracture of the distal part of the radius at the wrist joint) and shoulder fractures involving the neck of the humerus. These fractures result from a fall in which the patient lands directly on an outstretched hand or on the shoulder. In one series of patients with Colles’ fractures, 75% of patients were noted to have osteoporosis.9 Such fractures are usually characterized by swelling and deformity about the wrist, or, in shoulder fractures, an inability to move the shoulder. Treatment for both wrist and shoulder fractures is usually nonsurgical. In patients with Colles’ fractures, if displacement has occurred, reduction by an orthopedic surgeon is necessary as well as application of a splint that immobilizes the wrist but leaves the hand free. The splint is generally removed 4 to 5 weeks after the injury, and early wrist and hand motion is started. While the splint is on, careful attention must be given to the fingers, which may become edematous. Sensation and capillary refill, therefore, must be checked frequently, especially during the first week after fracture.
Fractures involving the surgical and anatomic neck of the humerus are best managed with a simple sling, which may be wrapped with an elastic bandage to the patient’s torso if pain is severe. Reduction, as a rule, is not necessary if displacement is not marked because these fractures tend to heal without problem. Shoulder motion is universal, and therefore some offset at the fracture site does not significantly affect function. The sling should be removed as soon as possible, based on the patient’s comfort, and certainly within 2 to 3 weeks after fracture. At that point, physical therapy is necessary to achieve return of motion of the shoulder. This may be slow because of the hemarthrosis that occurs in the shoulder joint with these fractures and the tendency for fibrosis and scarring to occur in the capsule of the shoulder joint. Most patients achieve satisfactory recovery of motion within 2 to 3 months after fracture.
Acute Management of Long Bone Fractures
When a geriatric patient is injured and a long bone fracture is suspected, the patient should be made comfortable by splinting the involved area with available pillows or cushions. If the limb is obviously displaced, gentle manipulation to a more normal alignment may make the patient more comfortable. Neurovascular examination of the distal limb should be performed to identify nerve or vessel injury. If the fracture is in the upper extremity, the area should be splinted with a sling wrapped around the torso to prevent movement of the limb away from the plane of the body. If the fracture is at the wrist, a splint can be fabricated from a piece of plywood and the limb wrapped with an Ace bandage applied loosely.
Long bone fractures of the lower extremity should be splinted with the limb in a comfortable position. Displacement of the fracture generally occurs with the initial injury, and further fracture displacement can be avoided by using fracture frames, which immobilize the patient and prevent limb rotation. Analgesics should be administered as needed to make the patient comfortable until appropriate radiographs have been obtained and transfer to an emergency room has been arranged.
Vertebral compression fractures are common in the elderly, particularly in postmenopausal women. These fractures may occur without trauma and may be associated with a sudden movement in bed or after lifting objects. Patients with these fractures complain of severe pain in the lower or midback. Usually these fractures involve the thoracic or upper lumbar vertebrae (Fig. 40-4). On radiographs a compression fracture secondary to poor quality bone is usually wedged anteriorly. In the most severe cases of osteoporosis spinal fractures may be multiple and may involve the entire vertebral body. As a rule, however, involvement or collapse that is strictly posterior may indicate a malignant process within the vertebrae and a pathologic fracture. Vertebral fractures tend to heal without surgical intervention, but because they may be extremely painful they limit the function and ambulation of the patient. Fortunately, these fractures generally stabilize quickly. A reduction in activity is recommended until the patient is comfortable, but a rapid return to the prefracture activity level is encouraged. A fitted thoracolumbar corset may be used in patients with ongoing pain and multiple compression fractures.
Figure 40-4 Upper lumbar vertebral fracture.
The shoulder is the most commonly dislocated joint in the geriatric patient. Generally, this injury is related to a fall on the shoulder. The patient experiences severe pain and is unable to use his or her arm. On physical examination an obvious depression is seen in the lateral shoulder. The humeral head may be palpable anterior to the glenoid. Shoulder dislocations are treated by reduction after an intravenous analgesic has been administered. A short period of immobilization in a sling is used after reduction. Early return of motion may occur with avoidance of external rotation and abduction movements for at least 6 weeks after the dislocation.
Osteoporosis is reviewed in detail in Chapter 21, but recommendations to prevent or ameliorate this disease must be constantly reinforced in affected patients. Dietary calcium supplementation remains important in all elderly patients, as is adequate vitamin D intake. Maintenance of activity and exercise programs, particularly those with weight-bearing stress, are vital to preserve bone mass.10,11,12,13 and 14 In patients with more severe osteoporosis, especially postmenopausal women, more vigorous pharmacologic management may be necessary. Estrogen or the use of biphosphonates is indicated in many of these women. Complications can occur with the use of all these agents, and therefore the patient must be appraised of potential hazards and must be monitored closely.
MANAGEMENT OF ARTHRITIS IN GERIATRIC PATIENTS
Arthritic afflictions of the skeleton are common in the elderly and often produce disabling pain and severe limitation of function.15 Osteoarthritis is the most prevalent type of degenerative disease, although rheumatoid arthritis, which is considered a disease of young women, does occur in older patients as well. Osteoarthritis may affect any of the synovial joints but is most common in the spine and the small joints of the hand, particularly the distal interphalangeal joints, and the knee, hip, ankle, and shoulder. When the upper extremity joints are affected, activities of daily living are compromised. Simple activities such as holding an object, putting on a coat, buttoning a shirt, or turning a key may become problematic. When the lower extremity joints are involved in osteoarthritis, the major functional result is a decreased ability to ambulate, climb and descend stairs, and arise from a seated position.
Further discussion of the pathogenesis and management of osteoarthritis is found in Chapter 39. In evaluating the patient with osteoarthritis, the entire complex of soft tissue, joint, and bone involvement should be considered. All of these structures are involved and can lead to pain, loss of motion, and dysfunction of the joint. Conservative and surgical treatment of osteoarthritis in the older patient is predicated on management of all anatomic structures involved in the arthritic process. Early in the disease when synovitis is most marked, medical management may be successful, but as joint destruction progresses, the mechanical component becomes predominant, and surgical correction or replacement of the joint must be performed to relieve patient pain and improve function.
Conservative Management of Osteoarthritis
Conservative management of arthritis in the geriatric population can be divided into two main categories: rehabilitative and pharmacologic. Rehabilitative treatment is directed at reducing the load to the arthritic joint and maintaining joint mobility and strength. Weight reduction that decreases the load on the joint significantly reduces pain in arthritic patients in whom the weight-bearing joints are involved. Avoidance of activities, particularly running or overhead sports in those with shoulder arthritis, will also reduce the load on the affected joint and relieve pain. However, although rest for a painful arthritic joint is helpful in the short term, prolonged periods of inactivity will lead to the more serious problem of immobility in the geriatric patient. The use of a cane will significantly reduce joint forces in all lower extremity joints and allow continuation of a walking program. The patient will rapidly modify his or her activities to lessen the load on an arthritic joint. Stair climbing will be avoided or will be performed one step at a time. Shopping will be done only as necessary. In patients with upper extremity arthritis, modifications will be made to reduce the need for overhead activities.
Exercise programs are important to maintain joint motion and strength in an arthritic joint. Both passive and active exercises should therefore be encouraged. Because pain may be aggravated if resistance is excessive in these exercise programs, resistance should be avoided. Simple antigravity exercises without weight-bearing are generally well tolerated. The shoulder quickly loses motion when arthritis develops, and, passive range of motion exercises of the shoulder must be maintained even if some pain occurs. This is best done by grasping a segment of a broomstick with both hands and using the uninvolved upper extremity to move the affected shoulder through a full range of motion.
A formal physical therapy program is recommended for the geriatric patient with osteoarthritis. A therapist can provide the full exercise program to the patient and determine which exercises exacerbate the pain. These exercises can then be modified immediately to allow strengthening of the intended muscle group without causing patient discomfort. Repetitive instruction in the correct method of performing the exercise and positive reinforcement improve compliance. Confusion about the type of exercise needed, the method, and the number of exercises performed can be avoided if the program is supervised and these questions are constantly addressed. Aside from strengthening exercises, a therapist can work with the patient to increase joint range of motion. This may be painful if the joint is badly destroyed and should be done only in a gently passive and assisted active manner. The patient should be encouraged to limit all attempted range of motion exercises if pain is significant. Joint inflammation becomes more marked, and effusion may ensue, leading to increased fibrosis and further joint contracture if continued painful range of motion exercises are pursued. In the patient with lower extremity involvement, the physical therapist can instruct the patient in the proper use of a cane and size it appropriately. Assistive devices such as modified eating utensils and buttoning hooks can also be provided by the therapist to improve upper extremity function.
Pharmacologic treatment is accomplished primarily with nonsteroidal anti-inflammatory medications and analgesics. Anti-inflammatory medications are particularly effective in the early stages of the disease when there is a significant inflammatory component and synovitis exists. As the disease progresses and joint incongruity becomes more severe, these medications tend to be less effective. Medical management is further highlighted in Chapter 39.
Hydrocortisone intra-articular injections are often efficacious in reducing joint inflammation and swelling. As with anti-inflammatory medications, these injections work best when they are used before severe mechanical joint changes have occurred. Depo-Medrol 40 to 80 mg is usually administered with 2 to 3 mL of 1% lidocaine after the skin has been prepared with Betadine. Joint contamination and infection is a catastrophe, and all injections into a joint must be performed in accordance with strict sterile technique as a minor surgical procedure. Intra-articular injections should not be performed more than three or four times yearly because damage to the joint surfaces may occur.
Surgical Treatment of Osteoarthritis
Surgical treatment is indicated in severely arthritic joints that are unresponsive to conservative treatment. Joint replacement is the procedure most commonly indicated when the joint has lost its articular cartilage surfaces. Joint replacement can now be performed in most peripheral joints including the shoulder, elbow, wrist, hand, hip, knee, and ankle. Hip and knee replacements are the procedures most often performed because of the frequency and disabling nature of arthritis that affects these two major weight-bearing joints. At the Hospital for Special Surgery in New York, for example, 2500 hip and knee replacements are performed yearly, but the combined number of other joints replaced is less than 100. The concept of joint replacement is to resurface the arthritic joint with a prosthetic surface that is usually made of metal and plastic (ultra-high molecular weight polyethylene). In geriatric patients these implants are generally fixed to bone with an acrylic cement called methylmethacrylate. Because soft tissue investments and ligamentous structures tend to be incorporated in the arthritic process, these structures must be balanced to provide joint stability, particularly in knee replacements. Bone loss may also be corrected by grafting excised bone into bony defects and supporting the implant on these grafted surfaces (Fig. 40-5). More options are available today in terms of augmentation of implants to deal with specialized areas of ligament instability and bone loss in the patient undergoing revision knee replacement (Fig. 40-6).
Figure 40-5 A, Advanced osteoarthritis of right knee. B, Postoperative view of right knee with prosthetic joint in place.
Figure 40-6 Augmented prosthetic joint of right knee.
Operative technique and implant materials have improved dramatically during the past decade. Joint replacement is performed under regional anesthesia routinely with only light sedation. This is particularly important in geriatric patients, who do not tolerate general anesthesia well.16,17,18 and 19 Most procedures are completed within 2 hours. Blood loss from raw bony surfaces tends to continue even after the wound has been closed, and therefore blood levels can drop and transfusion may be required. Autologous blood donation programs are used routinely for most joint replacement procedures, and even geriatric patients tend to tolerate providing their own blood for these procedures.
Patients are usually hospitalized for 5 to 6 days until ambulation is possible in patients with a lower extremity joint replacement and when motion has begun in those with an upper extremity replacement. Physical therapy programs in the home are arranged after discharge, or the patient is sent to a rehabilitative center for more intense therapy. Recovery from joint replacement surgery, barring a complication, progresses rapidly, and most patients are ambulatory without assistive devices 2 to 3 months after the surgery.
Overall long-term results of joint replacement have been excellent. In patients with hip and knee replacements 10- to 15-year results show continued success rates in the 90% range 20,21,22 and 23 (Fig. 40-7). The most common causes of failure of joint replacement are related to breakdown of fixation of the device with time or to excessive polyethylene wear, which can lead to inflammatory cell production with release of osteolytic enzymes. Improvements in materials and techniques have lessened the incidence of both of these problems. Infection remains the most catastrophic complication that can occur after joint replacement. Deep periprosthetic infection involving the bone-cement-implant interface can be eradicated only by removing the implant and administering parenteral antibiotics for 6 weeks. The device is then reimplanted if there is no evidence of persistent infection. Use of this protocol at the Hospital for Special Surgery in over 400 cases has produced a success rate of 90% in patients with hip joint infections and 95% in those with knee replacement infections.
Figure 40-7 Left total hip replacement.
Bone quality is poor in geriatric patients, and periprosthetic fractures may occur after a fall. The principles of management of these fractures are similar to those of fractures described earlier, with internal fixation devices being used to stabilize the bone around the implant. If fixation of the implant has been altered by the fracture, the implant can be revised and the fracture stabilized at the same time.
Osteoarthritis may involve the spinal synovial articulating joints as well as the peripheral joints. In the spine, however, because of the close proximity of the neural structures, distal manifestations of the primary spinal arthritis may be seen. Therefore, paresthesias, numbness, and weakness may be secondary to nerve root compromise centrally. In the assessment of any spinal disorder it is important to perform a careful neurological examination. The presence of neurological loss is a significant finding and may lead to early decompression of either the nerve root or the spinal cord, depending on the location of the neural compression.
Osteoarthritis that affects the facets of the apophyseal joints in the spine leads to the same pathological progression of symptoms as that seen in the peripheral joints. Articular cartilage is lost as the load on the articulating bony surfaces increases. The biological response to these altered joint loads leads to the production of reparative tissue in the form of new bone and fibrous and cartilaginous tissue. These osteophytes then tend to limit joint motion further as their overgrowth further locks in the joint. These osteophytes and the degeneration of the intervertebral disk that is anterior to the nerve root lead to compression of the neural foramen through which the nerve passes. In the most severe form of the disease, the neural foramen is compromised and central narrowing of the neural canal occurs, causing possible compression of the spinal cord (above L1–L2) and cauda equina (below L1–L2). The full composite picture of disk degeneration and severe osteoarthritic facet joint involvement with neural compression is called spinal stenosis.