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3	Rhizoarthrosis Disorder of the carpometacarpal (CMC) joint of the thumb Instability of CMC is caused by rheumatoid arthritis, osteoarthritis or cumulative trauma, work-related or hobby-related Greater frequency among women (50-60 yy), most likely associated with post-menopausal induced ligament laxity
4	Structural and functional considerations CMC joint of the thumb consists of articulation between the base of the first metacarpal and the distal side of the trapezium The thumb permits a wide range of motion: palmar abduction-adduction, flexion-extension, rotation Motion peculiar to the thumb includes opposition, specifically designed by the opponens pollicis muscle and prehension
5	Increase in articular loading CMC normal functional performance requires a strength of 10 kg in palmar grip 3 kg in pinch Articular instability leads to arthritic evolutions, the onset of inflammatory disorders and further degenerations of
6	Clinical features Marked pain, exacerbated by pinch or grasping actions Weakness and reduced motion Osteophyte formation and in more severe cases Loss of stability Swelling and deformation Subluxation and crepitation
7	"This degenerative disorder" This degenerative disorder is classified according to the Nalebuff classification: 4 stages of progressive alteration of articular connection Eaton classification: 4 stages of subsequent pathological clinical symptoms
8	Therapeutic aims To decrease pain To alleviate inflammation To maintain stability and/or mobility To maintain or increase strength and function To reduce mechanical loading
9	Therapeutic strategies Passive stabilization wrist-CMC immobilization or short opponens splints Physical therapies scanty scientific evidence (Poole JU, 2000) Nonsteroidal anti-inflammatory drugs general or local administration Corticosteroid injections risks damaging superficial sensory branches of the radial nerve (Neumann A and Bielefeld t, 2003) Joint protection to avoid unnecessary stress to the base of the thumb Rehabilitative exercise to strengthen muscles of the thenar eminence (1st and 2nd stage Nalebuff class) Surgical intervention
10	"Inclusion criteria" Inclusion criteria Patients affected by rhizoarthrosis of the 1st or 2nd degree according to the Nalebuff classification Patients treated with other therapies with no clinical improvement Patients aged 18 - 65 yy Exclusion criteria Recent traumatic injuries Rheumatic systemic pathologies Other ESWT exclusion criteria
11	Treatment Number of sessions 2 Interval time 3 weeks Number of Shock Waves 500-600 per session Density of Fluxus Energy 0,08 mJ/mm² Treated area CMC joint Rehabilitation daily self-made
12	Clinical evaluation criteria Visual Analogical Scale Fisher Algometer measurement Pinch test and palmar grip test
13	Rehabilitation exercises The aim of the exercises is to improve muscular stability around the base of the thumb and maintain the strength required for functional activities Patients performed exercises to strengthen the muscles of both the thenar eminence and those which allow opposition in order to encourage joint stability Exercises should be prescribed within the light-to-moderate intensity range
14	Results: VAS
15	Results: pain response on Fisher’s algometer
16	Results: pinch test
17	Results: palmar grip test
18	Follow up evaluation The further clinical and functional improvement 3 months after ESWT is due to a reduction of pain therefore patients can perform their exercises much more easily they can perform their own activities with fewer problems and less pain
19	Considerations The results obtained showed a good response to ESWT in the medium-term with significant reduction of pain with an improved range of motion Limits of the study are restricted number of patients lack of non-treated control group
20	Discussion Despite the fact that ESWT is not indicated for arthrosis pathologies it would seem to be an interesting approach for patients affected by rhizoarthrosis at the early stages it was well tolerated and no adverse events were noted
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22	Conclusions In our experience, patients treated with ESWT showed good clinical and functional results had a better capacity to perform their own activity in the medium-term.
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