First Carpometacarpal Osteoarthritis

• Disease of the muscoloskeletal system #2 is about First Carpo-Metacarpal osteoarthritis.

First Carpo-Metacarpal Osteoarthritis: Definition and Epidemiology

• It represents 10% of all osteoarthritis in the body.
• It affects 20% of the world's population.
• It is more common in females.
• 6% of males over 45 years old are affected.
• 33% of postmenopausal females are affected.
• It is caused by the loss of cartilage surface in both epiphyses.
• The loss of cartilage leads to a shortening of the joint space causing contact between epiphyses, resulting in inflammation.
• It is due to a defect and oxidation stress of the cartilage cells that do not produce chondrocytes.
• It is very painful and can affect hand, shoulder, elbow, knee, hip, ankle, and spine joints.
• It is common on the base of the thumb due to frequent thumb movements.
• The engagement of the trapezius muscle to the first metacarpal bone leads to cartilage loss.
• The thumb, along with the shoulder, has one of the widest ranges of motion in the body.

First Carpo-Metacarpal Osteoarthritis: Etiology

• Multiple causes exits, including a genetic predisposition.
• It is a hereditary condition, worsened by issues like ligament laxity.
• Ligament laxity can cause subluxation at the first metacarpal bone, more than at the trapezium bone.
• The Anterior oblique ligament, also called Big ligament, rupture or laxity of which lead to an unstable joint which a subluxation of the first grade of the first metacarpus to the trapezium bone.
• A fracture at the base of the first metacarpal bone can lead to osteoarthritis if it involves the cartilage.
• Anatomical changes in the tendon structure of APL (abductor pollicis longus) can contribute.
• In trapezius dysplasia-hypoplasia, thinning of the trapezium bone leads to osteoarthrosis at the joint's cartilage level.
• It can also occur if the trapezium bone is in a vertical position, impairing the joint's function and wearing out the cartilage.

First Carpo-Metacarpal Osteoarthritis: Symptoms

• Early and late symptoms exist.
• Early symptoms include non-localized pain during grasping activities.
• Early symptoms include swelling that is painful when pressed on the thenar part of the hand.
• Late symptoms include increasing pain.
• Late symptoms include hypotrophy of the muscles of the thenar eminence.
• The "Z" deformities of the thumb occur with complete adduction of the first metacarpal bone, limiting the ability to grasp objects.
• All arthritis processes are degenerative.

First Carpo-Metacarpal Osteoarthritis: Diagnosis

• The Grind test involves grasping the patient's hand and reducing the subluxation of the thumb.
• A positive Grind test is very painful for the patient and may lead to a sound.
• The Lever test involves moving the base of the first metacarpal bone, checking joint stability and laxity.
• A positive Lever test will has pain perceived by the patient.
• The metacarpophalangeal station test: patient extends with resistance and it is positive if pain is perceived.
• Reduced pinch strength in thumb opposition may be indicative of arthritis.
• The Kapandji score measures the thumb's opposition, with a normal score around 10.
• A limitation in this grade suggests basal thumb osteoarthritis due to joint stiffness.
• A healthy person can achieve a score of 10 in the Kapandji test.
• Problem is the stiffness and not the the tendon being unhealthy.
• There is hypotrophy of the tendon due to joint stiffness.

Instrumental Diagnosis

• Radiological classification is an important classification for osteoarthritis. First Carpo-Metacarpal Osteoarthritis has 4 signs:
• Reduction of the joint line due to a loss of cartilage surface that is radiotrasparent.
• Sclerosis of the subchondral bone which presents whiter than the rest of the joint.
• Osteophyte, a ossification of the joint from calcification of bone.
• Gelled formation which is transparent on X-ray and remodeling inside the bone, therefore the bone being more fragile.
• In stage 1, there is a reduction of the joint line.
• In stage 2, small osteophytes appear.
• In stage 3, bigger osteophytes appear with subluxation at the base of the thumb.
• Stages are treated with conservative approaches while later stages are treated surgically,.
• Stage 4 has complete reduction of the joint line and acts as a fusion and a bigger osteophyte will be showing.
• Stage 5 involves the scaphoid, trapezium, and trapezoid joints with osteoarthritis on all 3 surfaces.

Treatment

• Conservative treatments include rest, education in the correct gripping techniques, and avoiding movements that induce pain.
• Treatments include Drugs, physical agents, and injections.
• Drugs like NSAIDs and physical therapy like ultrasound or laser therapy is used.
• Injection of cortisone is a palliative treatment that is guided by ultrasound.
• Surgical procedures may be considered when conservative options are insufficient.
• Arthrodesis involves fusing the joints with instruments like plates.
• Arthrodesis comes with problesm of post operative complications and limitations in range in motion.
• Complications include mobilization, vascularization, and infection.

Surgical treatment

• Complications include anatomical abnormality in the position where we speak about malunion where the right healing isn't on the correct position.
• It is suggested a cut in cartilage to join bones together.
• Biological arthroplasties removes the trapezium bone is and held it with tendon.
• Biological arthroplasties represent the gold standard.
• Biological arthroplasties uses 3 techniques include the interposition suspension.
• The other technique removes the trapezium and fix the first metacarpal joint with the tendon in interposition or suspension.
• It is very painful and takes very long, patient must have 3 weeks with brace and 3 months of physiotherapy.

Surgical Treatment Options

• Distraction arthroplasty involves creating holes in the metacarpal bones.
• Distraction arthroplasty permits maintain a wide joint line and resolve the subluxation.
• Interposition arthroplasty involves amputating a large incision to install tendons to hold in position.
• Suspensional arthroplasty involves removing the trapezium and putting flexor carpi in the base, holds tightly..
• Dual cap mobility prosthesis improves mobility, reduces the dislocation risk and can be introduce if other options don't work.
• Dual cap mobility prosthesis is fantastic and works with head and neck, it has modular parts.
• The first stage of treatment is conservatives, in case of failure a second stage is to perform a arthroplasty.
• Stage IV and V can undergo suspension arthroplasty.

Extensor Tendon Injury

• They are very frequent during trauma from knives or blades.
• It happens more around Christmas due to a lot of housewives being cooking and preparing food.
• Distal interphalangeal joint and distal metacarpal joint are the ones affected the most.
• Is surgery is made early it can be operated in 1 or 2 days without much problems as the the retinacula holds the tendon.

Mallet Lesion

• Common lesion is the rupture of the tendon in the distal interphalangeal joint.
• Due to more balance of one tendon over other resulting in Mallet Finger effect.
• Can be treated conservatively or surgically.
• Conservative solution is to apply a "stax" brace for 10 weeks.
• Alternative solution is to put a Kirschner wire that makes the joint immobile and not invasive.
• We can do pull out where needles secure the bone to maintain tension from the extensor tendon.
• After 4-5 weeks the tendon is integrated completely on the bone.
• If a fracture happens, surgeon can use Ishiguro to maintain reduction of the bone but is a problem if you risk not healing right and not good.

Flexor Tendon Injuries

• Can cause partial or complete rupture of the tendon.
• It affects superficial and deep flexors.
• These injuries are severe as the bone has tendons and arteries, nerves and small veins.
• Cutting one artery might lead to vascularization problems due to the limited blood supply for fingers from the two arteries.
• If a artery gets injured, it needs to be stitched to properly supply blood to the finger.
• Flexor injuries can be partial or complete : If up to two-thirds of the tendon width is injured, treatment is conservative with immobilization for 3 weeks.
• If more than the two- thirds, surgical intervention is required.
• Evaluate function of fingers to manage appropriately.
• Early treatment essential as the ligaments stems can retract.
• If treatment delayed beyond 12 hours the stems can retract to the wrist level.
• Surgery as soon as possible can prevent adhesion.

Five zones of flexor tendons

• Zone 1 is till the tip of the finger to the middle of the proximal. Involves in distal flexor.
• Zone 2 is at the middle of the promixal the distal crease (no man's land), more prone to adhesion after surgical repair.
• Zone 3 is at the distal palmar till the carpal ligaments, careful to handle damage surrounding structures.
• Zone 4 is from the transverse carpal ligament to the wrist crease, crucial for gripping etc.
• Zone 5 is froms wrist to forearm requires tissue damage repaired as well.
• Zone 5 needs to be maintained in tension for proper healing.
• Rehabilitation is a vital part.
• 1 week the area will stay completely immobilized.

Sport Injuries

• Injuries in professional athletes are managed differently because of the functional demands.
• Types of injuries include Synovitis, Sprains and Fractures
• Synovitis is an inflammatory condition caused due to capsular tissues and repeated movements and inflammation.

De Quervain Disease

• Affects first part of extensor retinaculum by inflammation.
• It affects abductor pollicis longus and the the extensor pollicis brevis tendons.
• Overusing syndrome that leads to the inflammation of the tendons, can have corticosteroid injections.
• Sugery is preferred with a minimal incision releasing compartment in the retinaculum.
• Goal is to release first compartment and does not affect motion.
• Synovitis of Finger
• Flexor tendons get locked within the A1 and A2
• Conservatives include corticosteroid injections.
• Surgical involves transverse incision release of the a1 pulley.
• Surgical can sometimes damage the essential tendon in the A2 pulley, only the A1 is released.
• Anti doping prohibits glucocorticoids during some routes.

More on Sport Injuries

• Glucocorticoid steroid injection it needs the TUE form to inform the anti doping commitee.
• Only corticosteroids are allowed if the patient life is in danger.
• Athletes have 3 or 4 rehabilitators 24/7 which makes a significant impact on athletes since intensive care enables faster recovery.
• Sprain injuries generally occur forced on ulnar deviation, may cause Radial deviation injuries are less frequent.
• Most likely bones is first row of carpal.
• Bones include scaphoid, lunate, trilateral, pisiform.
• Scaphoid and lunar have to be checked for instability.
• An x ray helps identify the position of the bones.
• Dorsal rotation called DISI
• Polar rotation is PISI

Instability

• Rupture might affect scaphoid-lunate ligaments.
• X ray is very important to check condition.
• Check for gap in bones from semilunar area to the ring sign.
• MRI analysis by stages of lesions : -partial ligament stretching damage, and also complete ligament damage followed by stabilizers damage to scaphoid and lunars.
• SLAC - Capitates get blocked in wrist leading to severe pain.

More sport Injuries

• SLAC prevention through an early MRI.
• Acute is like 0-15 days, subacute is 15-30 and chronic is more than 30.
• For stage 1 watsons use cast.
• If pain and instability persist surgery is necessary.
• Minimally invasive K wire reduction.
• Rehab begins after K-Wire removal.
• Athletes return to sports quick using this method, but can be problematic in non athletes with wrist fractures.
• Fibrotic tissue reconstruction.
• Fixating capsule at anchor, maintaining tension to reconstruction of ligaments.
• Dorsal hyper extension = dissociation.
• K wire inserted for 2 weeks, and if injuries are chronic its extended.
• Scapholunate is not only damages part.

More details on Sport Injuries

• The TFCC includes radioulnar ligaments and the radioulnar joint.
• It ruptures from the one or both ligaments which causes instability can be dorsal displacement of the head causing discomfort.
• Reviewing what caused the injury, look for any extra pain.
• X Ray to determine lessions (MRI or CT is optional).
• Arthroscope can direct visualization of ligaments.
• Treatment on severity for the injury is key to the action plan.
• Stener Lesion is an injury involving the ulnar ligaments of the thumb (skiers thumb).
• Check thumb radial motion for this disease.
• Treatment options range from cast to a major surgery fixing ligaments with anchors.
• Immobilization lasts for 3 weeks.