The hip bone is formed by the fusion of the ischium, pubis and iliac bones which meet at the acetabulum. Anteriorly, the pubic bones articulate at the symphysis pubis. Posteriorly the iliac bones articulate with the lateral surface of the sacrum. The sacro-iliac joint is a synovial joint of the plane type and its strength depends on the posterior and anterior sacro-iliac ligaments.
The hip joint is a ball and socket type of joint. Its strength is dependent on the deep acetabulum and on muscle action rather than ligaments. The most important is the Y-shaped ligament of Bigalow which lies anteriorly and is the strongest ligament in the body .
The important anatomical landmarks are: 1. The head of the femur which can be felt in the ilium with the femoral artery lying in front of it just below the middle of Poupart’s ligament 2. The greater trochanter 3. The anterior superior iliac spine 4. The tuberosity of the ischium.
Nelaton’s line is drawn from the tuberosity of the ischium to the anterior superior iliac spine. The tip of the greater trochanter just touches this line in the normal limb. Bryant’s triangle is drawn by dropping a perpendicular from the anterior superior iliac spine onto the bed on which the patient rests. The distance from this line to the tip of the greater trochanter is compared with the other side.
An oblique plane passing through the promontory of the sacrum behind, and the arcuate line in front divides the pelvis into true and false parts. The false pelvis is an expanded part of the cavity lying above and in front, the true pelvis lying below and behind the pelvic inlet.
Flexion of the hip joint is limited by the abdominal wall when the knee is flexed. Tension in the hamstring limits flexion of the hip to about 90 to 100° when the knee is extended. Hyperextension of the hip is limited by the strong iliofemoral ligament of Bigalow. Abduction is limited by the pubofemoral ligament and by tension of the adductor muscles. Adduction is limited by contact with the other limb. Tension of the lateral rotator muscles and the ischiofemoral ligament limit medial rotation while lateral rotation is limited by the medial rotators and the iliofemoral ligament.
SOFT TISSUE INJURIES OF PELVIS AND HIP
Bruising in the gluteal region
Superficial bruising occurs with pain and tenderness at the site of the injury and the contusion can be seen.
This consists of ice packs in the initial stage followed by local massage and exercise to promote the absorption of the haematoma. Injection of local anaesthetic (1% plain) plus lignocaine may help the absorption.
Deep bruising may produce a large haematoma which can be seen and felt very quickly due to the looseness of the connective tissue of the buttock.
In minor cases ice, and contrast baths later, may be satisfactory. If the swelling is large it may have to be aspirated either with a needle or through a small incision under a local anaesthetic. This limits the pain and stiffness which often follows such an injury and enables active treatment and exercise to be carried out finally.
There may be a strain or tear of muscle origin from the iliac crest, the ischial tuberosity or the adductor region. A flake of bone may be avulsed from the muscle origin at the time of the injury which can be seen on x-ray examination. Examination of the site shows tenderness and swelling.
In the early stages cold and pressure should be applied to the painful area and later, as the swelling and tenderness subside, heat and graduated exercises. Ultrasound may help the painful area, and injections of hydrocortisone also help relieve pain.
These injuries tend to recur, but they can be prevented by careful ‘limbering up’ exercises before taking part in sporting activity. Some cases can become chronic with calcification in the muscle origin. Treatment with an injection of hydrocortisone and physiotherapy in the form of short wave diathermy and gende stretching exercises, may help the pain and stiffness.
Pain from injury to the hamstring origin at the ischial tuberosity may be similar to the sciatica from a disc lesion of the lower lumbar spine. Examination of the spine and a negative Lasegue’s test with no neurological signs will help in the diagnosis.
FRACTURES OF THE PELVIS
These may occur in rugby football, or from falls at speed from motor cars, cycles or horses.
Fractures of the false pelvis along the pelvic ring
These fractures may be due to a direct injury of the ilium or an indirect injury when the trunk muscles are avulsed from the iliac crest. In the same way the sar-torius may pull off the anterior superior iliac spine and the straight head of rectus may pull off the anterior inferior iliac spine. There may be an avulsion from the ischial tuberosity due to a pull of the hamstring muscles causing ischial apophysitis. This is possible, for example, in the lead leg of high jumpers using the straddle technique.
There is tenderness and swelling at the site of injury which is painful and swollen. Later, bruising will occur. An x-ray will confirm this fracture.
In the early stages cold and pressure with rest will limit the bruising and swelling. Later, heat with gentle exercises as soon as possible should be started. Operative treatment is rarely indicated. Ultrasound and an injection of hydrocortisone may be needed for any local painful area.
Fractures of the true pelvis
There are three main types: 1. Solitary fracture of a pelvic bone 2. Intra-articular fracture 3. Disruption of the pelvic ring.
Solitary fracture of a pelvic bone
This may affect the pubis, ischium, sacrum or coccyx. Symptoms include pain and tenderness at the site of injury; the patient can walk. The injury is characterised by tenderness at the fracture site with some swelling; the limbs are equal in length; shock is minimal. X-rays confirm the fracture.
Bed rest for a few days is advised until the pain has lessened. This is followed by heat and gentle exercises.
Here the posterior wall of the acetabulum may be fractured with a dislocation of the head of the femur as well. There may be a central dislocation of the head of the femur. The patient complains of pain about the hip joint. There may be some stiffness at the joint but no shortening of the leg. The sciatic nerve may be damaged in the posterior wall fractures of the acetabulum with weakness of dorsiflexion of the foot. X-rays confirm the fracture.
Reduction of the dislocation and internal fixation of the posterior fragment of the acetabulum may be necessary. Rest in bed until the fracture is healed will be required, followed by partial weight-bearing with crutches. Fractures of the side wall of the acetabulum require traction for about six weeks; no weight-bearing is allowed for three months and this is followed by gentle weight-bearing for a further three months. Aseptic necrosis of the head of the femur may occur in one year and osteoarthritis may develop in some cases after five years.
Disruption of the pelvic ring
In this type of fracture there may be damage to the urethra, the sciatic nerve or a major blood vessel in the pelvis. There are three types of fracture which have one thing in common, both sides of the pelvic ring being broken causing an unstable pelvis.
The crush injury: The patient complains of pain in the pelvis. He is shocked and cannot stand. There is pain over the front of the pelvis which is tender. The legs show no shortening and there is no excessive rotation in either leg. X-rays show a fracture of the pubic and ischial rami on both sides.
There may be damage to the urethra in this type of fracture and this is suspected if blood is seen at the external urinary meatus.
The urethral damage may have to be repaired. The fracture of the pelvis requires no special treatment except rest in bed till the patient can raise his legs from the bed. This takes about three weeks: he then can get up using sticks and will become more mobile as the pain becomes less.
Hinge separation of the symphysis: This is caused by a rolling type of injury, the force pushing the ilium on one side, downwards and outwards. One sacro-iliac joint is hinged open and the symphysis separates like an oyster. The patient complains of pain in the pelvis and cannot stand up on his feet. The gap can be felt in the symphysis and the leg on the damaged side lies in external rotation with no shortening. X-rays confirm the damaged pelvis.
Complications include severe intra-pelvic bleeding, but damage to the sciatic nerve or urethra is rare.
The disruption of the pelvis is controlled by a firm binder. The patient remains in bed for about six weeks after which walking exercises can begin.
The vertical fracture of the pelvis: This is caused by a fall from a height landing on one leg. This could happen, for example, in rock climbing or in some imperfectly executed gymnastic routines. The patient complains of pain in the pelvis and cannot stand on his feet. There is pain and tenderness on the symphysis and sacro-iliac joint on the same side. The leg on that side is shorter due to the pelvic bone being pushed up on that side. X-rays confirm the injury.
Complications include possible intra-pelvic bleeding and often damage to the sciatic plexus.
Strong skeletal traction on the leg reduces the upward displacement of the ilium, and traction on the leg is maintained for six weeks. Weight-bearing is not allowed for about three months.
FRACTURES OF THE NECK OF THE FEMUR
These are rare in young people, though the possibility must be borne in mind in hip injuries. This fracture can result from cycling falls at high speed. The possibility of a slipped upper femoral epiphysis must be remembered.
DISLOCATIONS OF THE HIP JOINT
This occurs when the leg is forced into abduction and external rotation. The main sign is that the leg Ues in external rotation, flexion and abduction. The head of the femur can be felt in the obturator foramen. X-rays confirm the diagnosis and whether a fracture is present as well.
Complications may include avascular necrosis of the head of the femur. There may be damage to the sciatic nerve and stiffness due to myositis ossificans.
Under a general anaesthetic the hip is manipulated into position. Sometimes the head of the femur may be button-holed in the capsule or caught in the tendon of the psoas muscle and an open operation is required to reduce the dislocation. The leg is then immobilised on traction for six to eight weeks.
This occurs when the femur is forced backwards with internal rotation and adduction. There may be a fracture of the posterior wall of the acetabulum as well. The leg Ues in adduction and internal rotation with flexion of the hip joint.
There is sometimes damage to the sciatic nerve, avascular necrosis of the head of the femur or myositis ossificans.
The hip joint is reduced under a general anaesthetic. If there is a fracture of the posterior wall of the acetabulum, the reduction may be unstable and the bony fragment may have to be replaced and fixed by means of a screw. Traction is applied as for an anterior dislocation.
This is a painful inflammation of the symphysis pubis due to chronic inflammation. It is more common in footballers but may occur in runners and walkers.
The patient complains of pain in the groin which may spread to the adductors, hip or external genitalia. The pain is relieved by rest and made worse by hip movements especially rotation and leg strains on the pelvis by contraction of the rectus abdominus. There may be a history of slight fever. An erythrocyte sedimentation rate (ESR) and white blood cell (WBC) count may sometimes be raised though not always. X-rays may show a widening of the pubic symphysis with calcification in the later stages.
This is symptomatic and consists of limiting physical activity until the symptoms are better. Phenylbutazone (200mg) three times daily with meals may also help and short wave diathermy may relieve pain. When the pain has subsided, gradual resumption of physical exercises will be required or the pain will return.
Chronic rheumatic diseases such as ankylosing spondylitis and Reiters disease must be excluded. Chronic adductor strains may also cause symptoms which are somewhat similar.
SPRAIN OF THE HIP JOINT
This occurs after a twisting injury to the hip. The patient develops a painful limp soon after the injury and complains of pain over the front and inner side of the hip. The pain may be referred to the inner side of the knee and thigh. There is tenderness over the front of the hip joint which is held in flexion and abduction; movements are painful. An aspiration of the joint may be carried out to exclude infection. X-rays are taken to exclude a fracture or other disease such as infection or tuberculosis.
Rest from weight-bearing is essential in the early stages with the patient walking with crutches. A firm supporting spica bandage of crepe will help relieve the pain and non-weight-bearing exercises are begun as soon as possible. As the pain and muscle spasm subside, weight-bearing may then be resumed.
This bursa lies between the deep surface of the fascia lata and the superficial surface of the greater trochanter with the gluteal muscle insertion. It may be inflamed by a direct blow on the trochanter or by the fascia lata slipping over the trochanter in vigorous exercises.
The patient complains of pain over the greater trochanter which has a deep aching character. It is more common in women than men, and the condition is aggravated by a trick movement which can make the tensor fascia lata slip over the trochanter by flexing the hip at the same time as the gluteus maximus is contracting. There is tenderness over the greater trochanter and pain when the fascia lata moves over the trochanter in flexion and extension of the hip. X-rays exclude any underlying bone damage or disease.
Rest from training; short wave diathermy helps resolution of the early acute cases. Hydrocortisone may be given by injection into the bursa. In some cases surgical division of a tight band of fascia lata may be required.
AVULSION FRACTURES OF THE GREATER AND LESSER TROCHANTER Avulsion fractures of the tip of the greater trochanter are caused by a sudden contracture of the gluteus medius. The patient complains of sudden pain over the tip of the greater trochanter, and walks with a limp. Signs include tenderness over the tip of the greater trochanter. There is a loss of power of abduction of the hip which causes a positive Trendelenburg’s test, I.e. when weight is put on the injured leg in standing the opposite hip drops rather than rises. X-rays confirm the fracture.
Mild cases of strain may settle quite quickly but the unstable fractures require internal fixation by figure-of-eight wiring.
Avulsion fractures of the lesser trochanter are caused by a sudden contracture of the psoas muscle. The patient complains of sudden pain while running or kicking; the pain being felt in the adductor region of the thigh. Bruising follows quite soon after the injury. There is painful tenderness over the lesser trochanter region with pain on adducting the leg at the hip joint. X-rays confirm the injury.
As soon as the pain allows, non-weight-bearing with gentle exercises is the best treatment. As the pain diminishes more vigorous exercises are commenced. Surgery is not required.
SOFT TISSUE INJURIES OF THE THIGH
This occurs after a direct injury to the thigh and causes bleeding in and around the thigh muscles .
The patient stops playing and complains of severe pain which is caused by pressure in the muscle due to bleeding. The pain is at the site of the injury and the patient also complains of stiffness in the thigh with difficulty in walking. There may be a superficial abrasion of the overlying skin with swelling and tenderness over the injured muscle.
Immediate application of a cold compression bandage helps to limit the bleeding. In severe cases the patient is put to bed for a day or so, to limit bleeding. Large collections of blood may have to be drained surgically. In less severe cases limitation of activity is immediately enforced with no attempt to help the pain by gentle exercise. In this way the onset of myositis ossificans, I.e. calcification of the haematoma by osteoblasts spreading from the injured periosteum, is less likely. As the condition settles, gentle graduated exercise is begun; short wave diathermy will help to encourage absorption of the haematoma and relieve muscle spasm.
This commonly occurs in the rectus femoris muscle but may also be found in the adductor muscles or in the hamstrings. It is interesting to note that the muscles which develop these injuries, act on two joints, flexing one and extending the other. As the muscle is relaxing a sudden strain is put upon it causing the tear before the muscle has properly relaxed. The strain may be either an indirect injury or the result of a direct blow over the site of the injury when the muscle is contracting.
The patient complains of pain at the site of the injury which is severe at first and later becomes more dull in nature. There is tenderness at the site of the injury where a gap may be felt. Later, swelling occurs which may be quite marked and may cause bruising at a considerable distance from the injury. There is pain when the muscle is tensed which limits activity.
Cold pressure bandaging helps to limit the bleeding; gentle exercises as soon as possible after the injury are advised. Injections of hydrocortisone with local anaesthetic and hyaluronidase (Hyalase) will limit adhesion formation later. Muscle spasm is helped by short wave diathermy. Late cases of adhesion formation and stiffness may require gentle manipulation under a general anaesthetic to relieve the pain and stiffness of the injured hamstring. In some cases the damage to the fascia lata may cause a muscle hernia which, if it becomes a nuisance, may have to be repaired surgically. Hamstring injuries, where the tendon is pulled a little out of the muscle belly, require care in rehabilitation to prevent recurrence. A careful examination of the patient’s running technique is required.
This commonly affects the biceps femoris tendon at its insertion into the head of the fibula rather than the other hamstrings where the injury is where the tendon leaves the muscle belly. In injuries to the biceps tendon the usual symptom is a complaint of pain at the outer side of the knee, which is made worse by running, or felt on getting up from squatting. The medial hamstrings produce pain at the level of the junction of the middle and lower thirds of the thigh along the postero-medial border.
In injuries to the biceps tendon there is tenderness at the insertion of the biceps into the head of the fibula. Flexion of the knee allows the injured biceps tendon to be removed away from the lateral joint line, thus differentiating it from an injury to structures on the outer side of the knee. X-rays show no bone damage. In late cases there may be a little calcification over the head of the fibula where the biceps tendon is attached.
This is on similar lines to a tennis elbow with ultrasound treatment and hydrocortisone injections into the painful muscle .
FRACTURES OF THE SHAFT OF THE FEMUR These occur in the course of various sporting activities and treatment is on the accepted orthopaedic lines for such fractures. It is important to remember that these fractures can cause extensive bleeding which leads to shock. A litre or more of blood may be lost into the soft tissue. The bleeding and shock can be limited considerably by careful handling of the patient and early splinting of the fracture before transporting the patient to hospital.
Careful examination of the pelvis and hip joint will help to localise the site of the injury. Gentle movements which do not put tension on a damaged ligament do not cause pain. Stretching a damaged ligament does cause pain and the movement is restricted. Careful palpation of the site of injury will help in identifying the injury.
Pain due to bruising of the articular cartilage of the joint may not appear for a week or so after the injury due to vascularisation of the injured cartilage. As the vascularisation becomes less with healing, so the pain lessens and exercises can be encouraged. Gentle movements, as the pain becomes less, will help limit the formation of adhesions.
Adhesion formation causing stiffness is treated by manipulation under a general anaesthetic when the pain has resolved. Such a manipulation is carried out firmly and steadily, taking care to break adhesions in all directions. If the manipulation is carried out too early or inefficiently, irritation of the joint and its musculature and more adhesion formation will follow.