Atypical influence of biomechanical knowledge in Complex Regional Pain Syndrome-towards a different perspective on body representation.

Part of the multifaceted pathophysiology of Complex Regional Pain Syndrome (CRPS) is ascribed to lateralized maladaptive neuroplasticity in sensorimotor cortices, corroborated by behavioral studies indicating that patients present difficulties in mentally representing their painful limb. Such difficulties are widely measured with hand laterality judgment tasks (HLT), which are also used in the rehabilitation of CRPS to activate motor imagery and restore the cortical representation of the painful limb. The potential of these tasks to elicit motor imagery is critical to their use in therapy, yet, the influence of the body's biomechanical constraints (BMC) on HLT reaction time, supposed to index motor imagery activation, is rarely verified. Here we investigated the influence of BMC on the perception of hand postures and movements in upper-limb CRPS. Patients were slower than controls in judging hand laterality, whether or not stimuli corresponded to their painful hand. Reaction time patterns reflecting BMC were mostly absent in CRPS and controls. A second experiment therefore directly investigated the influence of implicit knowledge of BMC on hand movement judgments. Participants judged the perceived path of movement between two depicted hand positions, with only one of two proposed paths that was biomechanically plausible. While the controls mostly chose the biomechanically plausible path, patients did not. These findings show non-lateralized body representation impairments in CRPS, possibly related to difficulties in using correct knowledge of the body's biomechanics. Importantly, they demonstrate the challenge of reliably measuring motor imagery with the HLT, which has important implications for the rehabilitation with these tasks.

[Eccentric strengthening in the treatment of tendinopathies]. / Intérêt du renforcement musculaire excentrique dans le traitement des tendinopathies.

Tendinopathies show a high prevalence within the general population and sport. Despite recent progress in understanding and treating soft tissue injuries, this pathology remains a therapeutic challenge. Rehabilitation in eccentric mode has shown promising results but the mechanisms by which eccentric contractions aid in healing are still difficult to determine. Based on a review of the literature and our own clinical experience, we recommend some rehabilitation protocols and consider the various hypotheses presented in the literature.

[The first Belgian hand transplantation case. Nine years follow-up]. / Le premier cas belge de transplantation de main. Résultat à neuf ans.

The authors report the clinical result at 9 years followup of a unilateral hand transplantation performed on the dominant side after traumatic forearm amputation. The patient is back to work and sporting activities. The allograft has been fully incorporated into his self-image. The satisfaction index is 10/10, the DASH 5/100, and the 400-points score 68.1 %. The Lanzetta HTSS score is 91 (excellent). Good function of extrinsic and intrinsic muscles is observed. The grasping strength is markedly decreased (7.4 % as compared to the normal non-dominant side). The patient has experienced several rejection episodes, controlled by the immunosuppressant drugs.

The first Belgian hand transplantation--37 month term results.

The first Belgian hand transplant was a 22 year-old man with a traumatic amputation of his dominant hand at the junction of the middle and distal thirds of the forearm. The donor and recipient had three HLA mismatches. The cross-match was negative. The total ischaemic time was slightly over 6 hours. Immunosuppression included antithymocyte globulins at induction and tacrolimus, mycophenolate mofetil and prednisolone as induction and maintenance therapy. There has been no episode of rejection. The only significant complications, except for transient hyperglycaemia, were psychological. At 37 months post-transplantation, the patient has fully incorporated his transplant into his self-image and is back at work. He has good sensibility (two-point discrimination of 6mm at the thumb and index finger pulps), acceptable wrist and finger motion with functioning intrinsic muscles. According to Chen's criteria, the result is good to excellent.

Trapeziometacarpal osteoarthrosis: clinical results and sonographic evaluation of the interposed tissue after trapeziectomy and first metacarpal suspension by external minifixation at a minimal two-year follow-up.

Among the surgical options to treat trapeziometacarpal osteoarthrosis, trapeziectomy has been criticized as unable to prevent postoperative collapse of the thumb, causing painful scapho-metacarpal impingement. The implantation of an external minifixator between the first and the second metacarpals for sufficient time has been proposed to maintain the postoperative space created by the bone resection to allow the development of a resistant interposed fibrous tissue. Nineteen patients (16 women, 3 men, mean age 64.5 years) were evaluated at 3.3 years of follow-up after an unilateral trapeziectomy and first metacarpal suspension by external minifixation. Eighty-four percent of the patients were very satisfied with the operation. The mean DASH score was 27.7%, the pain 1.7/10 (Visual Analogue Scale), the opening angle of the first web 58.3° and the Kapandji opposition score 9.5/10. Sonography demonstrated the existence of a strong fibrotic interposed tissue, preventing scapho-metacarpal impingement. The mean height of the trapeziectomy space (8.4mm) was maintained upon active pinch and maximal traction on the thumb. A significant atrophy of thenar muscles was also demonstrated, except for the Abductor pollicis brevis. In conclusion, total trapeziectomy with external minifixation provides acceptable clinical results, stabilizes the base of the thumb and prevents scapho-metacarpal impingement. The study brings also important new information about the nature of the interposed tissue in the trapezial space and about the state of the thenar muscles after trapeziectomy.

Arthrodesis of the wrist with bone autograft and Hoffmann external fixation.

We report a series of 29 cases of wrist arthrodesis using a radiometacarpal half-frame or triangular Hoffmann configuration, bone autograft, and relocation of a retinacular rectangular flap under the extensor tendons to prevent adhesions. No splint or plaster cast has been used. Early active motion of the fingers was encouraged. The average duration of follow-up was 4 years. Bone healing was obtained in 27 patients after 104 days on average. All patients regained full finger movements and rotation of the forearm. Nine patients were reassessed on average 7.2 years after the arthrodesis: the VAS for pain at rest was 2.4/10, the DASH score 33/100, the grip strength 75% of the contralateral side on average.

Tolerance of upper extremity pneumatic tourniquets and their effect on grip strength.

This study was undertaken to evaluate tourniquet tolerance in healthy people. An arm tourniquet was inflated to 100 mmHg above systolic blood pressure for 21 minutes. We measured pain and grip strength before, during and at various times after deflation. We tested 40 subjects (20 women and 20 men) with an average age of 38 (range 22-58) years. Eight individuals did not tolerate the tourniquet for this length of time and the test was stopped. Visual analogical scale had a globally linear increase during tourniquet application. We noted a sensation of well-being just after deflation, quickly replaced by pain in the tested limb due to limb reperfusion. We also noted a significant loss of strength in the tested limb, which completely recovered by 48 hours. We also observed a significant loss of strength in the contralateral hand, which also recovered by 48 hours. The possible reasons for these temporary losses of strength in both the ipsilateral and contralateral limbs are discussed.