The aim of this work is to present a clinical case of wrist arthroplasty failure due to chronic infection and try to discuss and draw a therapeutic approach (algorithm) for similar cases taking in consideration the degree of osteolysis, the presence of detachment and inherent instability and the condition of the soft tissues. The authors report a case of an individual, male, 58 years old, manual worker, that appears with pain and inflammatory signs on right wrist arthroplasty, with fistulous track. The revison procedure was performed in 2 stages: the first stage revision consisted on removal the implant, debridement and interposition of cement spacer with antibiotics and immobilization, the second stage revision a radio-metacarpal arthrodesis with plate and interposition of autologous graft harvested. The improvement of the implants in recent years have contributed to the increasing use of arthroplasty as a treatment option with good results. Although it presents itself with an attractive option in terms of future functional capabilities, arthroplasty remains with some risks and have a higher rate of complications in the medium and long term than fusion, so the selection of patients should be careful. The main problem of wrist arthroplasty revision is due to bone stock loose to promote fusion and the shortening after implant removal. At 1,5 years follow-up, we denote a higher patient satisfaction, without pain, radiological fusion and 28 points in DASH score. The success of wrist arthroplasty depends on careful patient selection, careful preoperative planning, rigorous technique and an appropriate program of functional rehabilitation. The wrist arthrodesis can always be seen as an ultimate salvation procedure in the treatment of failure of wrist arthroplasty, either a mechanical or infectious failure

Introduction. Total Wrist Arthroplasty (TWA) for Rheumatoid Arthritis (RA) of wrist allows pain relief and preservation of the movements. Aims. The aims of current study were to evaluate outcomes of Universal-2® TWA at a tertiary centre. Methods. This was a retrospective review of case notes of 92 Universal-2® wrist replacements performed from 2003 to 2009. There were 63 female and 14 male patients. Ten patients had bilateral wrist replacements. There were 5 patients lost to follow-up and 2 patients died at 2 and 4 years following TWA, due to un-related causes. The available literature related to Universal implant was also reviewed. Results. The indication was RA in 83 wrists, 3 had severe osteoarthritis and one had post-traumatic arthritis following scaphoid fracture. Mean age was 60 years (26 to 86 years) and mean follow-up of 51 months (13 to 94 months). Post-operatively pain relief was achieved in 91.2% and patient satisfaction was 86%. Movements were preserved with mean dorsiflexion of 23. o. and palmarflexion of 21. o. An interim study of 34 patients showed VAS pain score improved from 5.4 to 1.7 and DASH score improvement of 14 points. Radiologically, intercarpal fusion was noted in 85% of the cases. Minor complications included; joint stiffness (10%, n=14), wrist pain (9%, n=8) and superficial infection in 2 cases (2.3%). Major complications were revision of wrist arthroplasty in 4.7% (n=4) and 3.5% salvage arthrodesis (n=3). Conclusion. Pain relief and patient satisfaction following wrist arthroplasty was consistently high in our series. The incidence of major complications was 8.1% in this study, compared to the literature review which shows rates of 12% for Universal-2® TWA and up to 50% in earlier Universal® implant. Universal-2® Wrist Arthroplasty is recommended for pain relief and preservation of function. Further studies are required particularly focusing on Carpal component loosening and long term outcomes

Wrist motion is achieved primarily via rotation at the radiocarpal and midcarpal joints. The contribution of each carpal bone to total range of motion has been previously investigated, although there is no consensus regarding the influence of each structure to global wrist motion. The objective of this comprehensive in-vitro biomechanical study was to determine the kinematics of the capitate, scaphoid and lunate during unconstrained simulated wrist flexion-extension. In addition, this study examined the effect of motion direction (i.e. flexion or extension) on the kinematics and contribution of the carpal bones. Seven fresh frozen cadaveric upper limb specimens (age: 67±18 yrs) were amputated mid-humerus, and the wrist flexors/extensors were exposed and sutured at their musculotendinous junctions. Each specimen was mounted on a wrist motion simulator in neutral forearm rotation with the elbow at 90° flexion. Passive flexion and extension motion of the wrist was simulated by moving a K-wire, inserted into the third metacarpal, through the flexion/extension motion arc at a speed of ∼5 mm/sec under muscle tone loads of 10N. Carpal kinematics were captured using optical tracking of bone fixated markers. Kinematic data was analysed from ±35° flexion/extension. Scaphoid and lunate motion differed between wrist flexion and extension, but correlated linearly (R‸2=0.99,0.97) with capitate motion. In wrist extension, the scaphoid (p=0.03) and lunate (p=0.01) extended 83±19% & 37±18% respectively relative to the capitate. In wrist flexion, the scaphoid (p=1.0) and lunate (p=0.01) flexed 95±20% and 70±12% respectively relative to the capitate. The ratio of carpal rotation to global wrist rotation decreased as the wrist moved from flexion to extension. The lunate rotates on average 46±25% less than the capitate and 35±31% less than the scaphoid during global wrist motion (p=0.01). The scaphoid rotates on average 11±19% less than the capitate during wrist flexion and extension (p=0.07). There was no difference in the contribution of carpal bone motion to global wrist motion during flexion (p=0.26) or extension (p=0.78). The capitate, lunate and scaphoid move synergistically throughout planar motions of the wrist. Our study found that both the scaphoid and lunate contributed at a greater degree during wrist flexion compared to extension, suggesting that the radiocarpal joint plays a more critical role in wrist flexion. Our results agree with previous studies demonstrating that the scaphoid and lunate do not contribute equally to wrist motion and do not function as a single unit during planar wrist motion. The large magnitude of differential rotation observed between the scaphoid and lunate may be responsible for the high incidence of scapholunate ligament injuries relative to other intercarpal ligaments. An understanding of normal carpal kinematics may assist in developing more durable wrist arthroplasty designs

Wrist motion is achieved primarily via rotation at the radiocarpal and midcarpal joints. The contribution of each carpal bone to total range of motion has been previously investigated, although there is no consensus regarding the influence of each structure to global wrist motion. The objective of this comprehensive in-vitro biomechanical study was to determine the kinematics of the capitate, scaphoid and lunate during unconstrained simulated wrist flexion-extension. In addition, this study examined the effect of motion direction (i.e. flexion or extension) on the kinematics and contribution of the carpal bones. Seven fresh frozen cadaveric upper limb specimens (age: 67±18 yrs) were amputated mid-humerus, and the wrist flexors/extensors were exposed and sutured at their musculotendinous junctions. Each specimen was mounted on a wrist motion simulator in neutral forearm rotation with the elbow at 90° flexion. Passive flexion and extension motion of the wrist was simulated by moving a K-wire, inserted into the third metacarpal, through the flexion/extension motion arc at a speed of ∼5 mm/sec under muscle tone loads of 10N. Carpal kinematics were captured using optical tracking of bone fixated markers. Kinematic data was analysed from ±35° flexion/extension. Scaphoid and lunate motion differed between wrist flexion and extension, but correlated linearly (R^2=0.99,0.97) with capitate motion. In wrist extension, the scaphoid (p=0.03) and lunate (p=0.01) extended 83±19% & 37±18% respectively relative to the capitate. In wrist flexion, the scaphoid (p=1.0) and lunate (p=0.01) flexed 95±20% and 70±12% respectively relative to the capitate. The ratio of carpal rotation to global wrist rotation decreased as the wrist moved from flexion to extension. The lunate rotates on average 46±25% less than the capitate and 35±31% less than the scaphoid during global wrist motion (p=0.01). The scaphoid rotates on average 11±19% less than the capitate during wrist flexion and extension (p=0.07). There was no difference in the contribution of carpal bone motion to global wrist motion during flexion (p=0.26) or extension (p=0.78). The capitate, lunate and scaphoid move synergistically throughout planar motions of the wrist. Our study found that both the scaphoid and lunate contributed at a greater degree during wrist flexion compared to extension, suggesting that the radiocarpal joint plays a more critical role in wrist flexion. Our results agree with previous studies demonstrating that the scaphoid and lunate do not contribute equally to wrist motion and do not function as a single unit during planar wrist motion. The large magnitude of differential rotation observed between the scaphoid and lunate may be responsible for the high incidence of scapholunate ligament injuries relative to other intercarpal ligaments. An understanding of normal carpal kinematics may assist in developing more durable wrist arthroplasty designs