Bilateral rhizarthrosis of both hands: oblique projection.rhizarthrosis is a pathology that most frequently affects postmenopausal women (16-25% of them).
When advanced it can constitute an important limitation of the functional capacity of the hand, pain, instability, deformity and loss of mobility.
Among the most frequent causes to produce osteoarthritis at this level, the most frequent are:
- Overstretching of the hand.
- Articular overuse.
- Genetic predisposition.
- Hormonal factors.
- Hyperlaxity.
- Idiopathic etiology. This is the main cause of gonarthrosis and coxarthrosis.
Only one third of the rhizarthroses are clinically significant and the patient requires medical assistance, medication and, occasionally, incapacity for work, especially because 30% of them are bilateral.
It is the degenerative arthropathy that causes the highest number of surgeries in the upper limb.
Clinic
The pain initially develops in crisis and slowly, especially in young women and manual workers.
It usually appears when the thumb is rotated, but also in repetitive movements and gripping movements.
The tenar eminence is usually very painful on palpation and tendinitis of the flexor carpi radialis may occur.
When the deformity progresses, the pain crises become more frequent and the muscles of the tenar eminence atrophy, appearing compensatory movements of the thumb to try not to lose strength.
The patient reports pain, stiffness, swelling and inability to perform daily activities. All this will be aggravated by movements and will cause the pain to spread to the forearm and elbow.
Another manifestation is the sensation of weakness in grasping or holding objects, which can lead to falls due to the decrease in the grip strength inherent to the lesion.
In the initial exploration we can find a deformity at the level of the trapeziometacarpal joint, with the characteristic sign of the shoulder that is due to the thickening of this joint, similar to the relief of the deltoid in the shoulder; another finding can be the progression of the thumb towards the center of the hand, causing the decrease of the first interdigital space.
It is important to see if there is osteoarthritis in other locations such as Heberden’s nodes or the presence of carpal tunnel syndrome, which coexists in 43% of cases.
There are two important and well-known maneuvers that exacerbate the symptomatology:
– The Cranck test consists of provoking pain by performing a compression on the axis of the first metacarpal, associating a flexion-extension movement.
– The Grind test is the same type of compression, but associating a rotation movement at the level of the TMC joint.
It is important to assess the space of the first commissure. As the disease progresses, compensatory deformities such as hyperextension of the metacarpophalangeal joint of the first finger occur.
Complementary examinations
The simple radiography is a fundamental tool for the diagnosis of this disease.
The projections that cannot be missed to complete the study of the hand and rule out or confirm this pathology are:
- AP and lateral of the trapezio-metacarpal joint and of the metacarpo-phalangeal joint.
- Commissure in maximum supination.
- AP of the wrist to rule out lesions associated with other levels in the carpus such as scapho-trapezio-trapezoid.
Conservative treatment
It is a symptomatic treatment of pain relief, which can delay surgery and significantly improve the clinical picture.
It should be started until the progression of the condition causes the patient to be incapacitated. It should be maintained as long as the symptomatology allows it.
Types of treatment
- Rest and/or change of activity. It is advisable to re-educate postural habits and functional patterns. Avoid forced positions.
- Analgesia and taking non-steroidal anti-inflammatory drugs.
- Local infiltrations with intra-articular corticoids to reduce inflammation and improve pain.
- Infiltration of hyaluronic acid. Its function is to strengthen the extracellular matrix of the cartilage with an analgesic effect. It is a slow-acting drug but it can slightly modify the course of the disease. All infiltrations are performed under ultrasound guidance. It is the most precise way to perform the infiltrations and to place the medication at intra-articular level.
- Infiltration of growth factors. They have a biological effect, with a decrease in inflammation and significant symptomatic improvement. They are undoubtedly one of the star treatments to improve symptomatology and avoid surgery.
- Rehabilitation treatment and appropriate muscle strengthening exercises. The main objective is the recovery of functional capacity, taking into account the needs of each patient, for this, treatment with Occupational Therapy is essential.
In this treatment we include:
- Design of graduated therapeutic activities aimed at:
- Gentle and painless mobilization, traction and distension of the thumb.
- Opening of the first interdigital space with correct alignment of the thumb to be able to manipulate large objects without causing joint overload.
- Performing thumb-index thumb-terminal pincer while maintaining the first interdigital space (corrected pincer).
- Strengthening. The adductor brevis together with the weakness of the tenar eminence musculature for opposition, is what causes the first commissure to narrow. By strengthening this opposing musculature, the APL and the EPL, we achieve dynamic postural reeducation of this joint.
- Orthoses and immobilizations: Their main function is to stabilize the base of the first metacarpal, trying to avoid the progression of the adduction of the first metacarpal as well as the subluxation of the base. In the most painful and disabling phase, the orthosis will be of immobilization or rest, and will be used diurnally and nocturnally. When the pain and swelling have subsided, the splint will be replaced with a functional splint that will allow the patient to perform most activities of daily living with good alignment (deformity correction) and without joint overload.
- Patient education in principles of joint protection and economy. It is essential to review with the patient those daily activities that generate the most pain. Once they are known, the patient will be educated on how to avoid stress positions and/or deformity through ergonomic principles during the performance of activities of daily living. As well as to plan the activities to be able to dose in the presence of fatigue and / or pain alternating periods of activity and rest. Finally, advice and training in support products or adaptations of utensils will help to reduce joint overload.