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Hand.Carpus.By Jon.Trister MD

Carpal arch consists of carpal bones and transverse carpal ligament (TCL). TCL attached to scaphoid and trapezium radially and the pisiform and hamate ulnarly. There are three muscles are known to originate from the TCL. Radially, abductor pollicis brevis and flexor pollicis brevis originate from the TCL. Ulnarly, a portion of the flexor digiti minimi brevis originates from the TCL.Some anatomy texts consider TCL as a part of the Flexor Retinaculum (FR)- Middle portion, other describe it as separate structure based on the functions of two which are quite different: FR performs predominantly proprioceptive and TCL stabilizing roles.
Tensions generated by TCL together with interosseous carpal ligaments determine the form, length, width, of the carpal tunnel. Content of the carpal tunnel and its relationship to the structure which form carpal tunnel will determine its function.
The form of the carpal tunnel is not static, but dynamic and changes depending on the tasks performed by writs, hands, and fingers.
There is a wrist retinaculum that perceives, analyzes, and communicates locally (local reflexes, mechanoreceptors)  and centrally (CNS) to coordinate the optimal function of the wrist and fingers. Form, direction, length, and width of the carpal tunnel are constantly changing depending on the tasks performed by the fingers and hand and adapt to optimize these functions.
Several muscles control TCL and subsequently carpal tunnel: Thenar, Hypothenar, interossei, lumbricalis, Flexor carpi ulnaris, Palmaris longus, palmar aponeurosis.
Information from distal parts of the hand ( MCP, PIJ, DIJ, A pulley, C pulley, joint’s capsule, synovium) reciprocally communicate with proximal structures: TCL, carpal joints and its capsules, distal pronators quadratus.
Flattening of the arch is responsible for symptomatology of the carpal tunnel.This occurs as the result of ligamental laxity of the TCL, intercostal ligaments and gravitational stress (Supine position make carpal tunnel flat and compress the contetnt of the carpal tunnel, including medial nerve and its supportive structures: vasa nervorum, nervi bervorum,vasa vasorum).
Nocturnal pain and numbness in the fingers are manifestation of compressive neuropathy of the median nerve which is getting worse in the supine position.

Hand instability may have various presentations

There are many different  manifestations of this process: Osteoarthritis, Enthesopathies, Neuropathies, Contractures, Deformities. All of these pathologies will be always present in various degrees.

Choice of therapy depends on degree of the damage, location of the predominant symptom, previous injuries, age of the patient, duration of the symptoms, previous treatments, and presence of other medical problems.

Clinical presentation never comes from one source.

Pain and instability of the scapho-trapezium-metacarpal complex associated with laxity of the transverse wrist ligament, laxity of the flexor and extensor retinaculum, weakness of the thenar and hypothenar muscles, palmaris longus.

Ligaments which connect carpal bones could be lax. This will preclude them from keepIng a normal arch of the palm.

Strength of the transverse ligament, elasticity of the inter-carpal ligaments, thenar and hypothenar strength and forms of the carpal bones will determine the volume of the carpal tunnel, interaction of the structures inside the tunnel, direction of the movement of the bones.

Transverse ligament attached to the scaphoid and trapezius on the radial side and to pisiform and hamate on the ulnar side. This anatomical connection controls stability of the scapho-trapezium-metacarpal joints and ulnar aspect of the hand. Palmar aponeurosis has direct connection to palmaris longus; and flexor carpi ulnaris controls transverse ligament attachment on the ulnar side.

Flexor and extensor retinaculum provide proprioceptive information to all these structures assuring coordinating activity. Stability of the distal RU junction controlled by dorsal and palmar ligaments , TFCC, pronator quadratus  and interosseous membrane; 

The proximal RU junction is controlled by annular ligament, it’s tension will be controlled by the action of the Biceps and pronator teres.

Thumb pain.

Treatment Prolotherapy. 15-20 cc 15 % dextrose.

Use 27 G needles. Target structures: 

Medial humeral epicondyle-flexor carpi ulnaris and pronator teres

Lateral elbow: If annular RU ligament is painful ( proximal RU junction);

Styloid process of the distal radius and dorsal aspect of the radius; Distal RU junction; TFCC; Entire capsule of the carpal joint on the posterior aspect.

Carpal ligaments: they keep the arch; Pisiform, Hamate, Base of the 5-th MC bone.

Then , scapho-trapezium-metacarpal joints: anterior , lateral and  posterior aspects

Consider scapho-lunate and luno-triquetral joints; 

Inject around capitate bone as well.

MCP joint and IPJ.

Carpal tunnel:

Treatment Prolotherapy. 15-20 cc 15 % dextrose.

Use 25-27 G needles. 

Target structures: 

Medial humeral epicondyle-flexor carpi ulnaris and pronator teres

Lateral elbow: If annular RU ligament is painful ( proximal RU junction);

Styloid process of the distal radius and dorsal aspect of the radius; Distal RU junction; TFCC; Entire capsule of the carpal joint on the posterior aspect.

Carpal ligaments; Pisiform, Hamate, Base of the 5-th MC bone.

Then , scapho-trapezium-metacarpal joints: anterior , lateral and  posterior aspects

Scapho-lunate and luno-triquetral joints; 

Transverse metacarpal ligaments and MCP joints

Inject around capitate bone as well.