simultaneous palmar dislocation of the scaphoid and lunate is rare [ 17 ] and has been classified into two types depending on whether or not the scapholunate ligament is intact .
ten patients with dislocation of the scaphoid and lunate as a unit have been described to date , as well as six patients with divergent dislocation [ 16 ] .
the patient described here is therefore the seventh with palmar - divergent dislocation of the scaphoid and lunate . in this patient
, the scapholunate and lunotriquetral ligaments were sutured through the dorsal approach , the anterior capsule was sutured through the palmar approach , and the scapholunate and lunotriquetral joints were fixed with kirschner wires . to our knowledge , this is the first report in which interosseous ligaments were sutured by open surgery for divergent dislocation of the scaphoid and lunate .
a 46-year - old man who fell from a height of 1.5  m onto his left hand was brought to the emergency center of our hospital and underwent a medical examination .
radiography of the wrist revealed palmar - divergent dislocation of the scaphoid and lunate ( fig .  1 ) but with no neurovascular disturbance in the hand .
seven days after the injury , open surgery was performed through the palmar and dorsal approaches .
the dorsal approach showed ruptures of the scapholunate and lunotriquetral ligaments , which were sutured with anchors .
the palmar approach showed an oblique tear of the anterior capsule , which was sutured with absorbable threads .
finally , the scapholunate and lunotriquetral joints were fixed with two kirschner wires , inserted from the scaphoid to the lunate and from the triquetrum to the lunate , respectively , and the wires were buried under the skin ( fig .  2 ) .
a short arm plaster splint was applied postoperatively ; 2 weeks later , it was changed to a removable splint and rehabilitation was started . as kirschner wires remained in the carpal bones , range of motion ( rom ) exercises of the wrist were restricted to avoid wire failure . at 7 weeks , the kirschner wires and splint were removed , and the patient was started on intensive rehabilitation for an additional 3 months . at the 1-year follow - up , the patient had returned to normal life and work and had no pain in his wrist , although wrist motion was still restricted .
measurements of wrist and forearm rom showed that right / left extension was 60/50 , flexion was 70/40 , supination was 90/80 , and pronation was 90/90. a hand dynamometer showed that grip strength in his left hand was 16  kg compared with 27  kg on the contralateral ( dominant ) side .
although we observed no evidence of dorsal or volar intercalated segment instability pattern deformity , radiography showed a break in arc ii of gilula s line between the lunate and triquetrum , as well as flexion deformity of the scaphoid ( fig . 
magnetic resonance imaging showed no evidence of avascular necrosis of the scaphoid and lunate ( fig . 
1radiographs at initial diagnosis showing palmar - divergent dislocation of the scaphoid and lunatefig . 
the scapholunate angle was 54 and the radiolunate angle 6. gilula s line was well - regulatedfig . 
the scapholunate angle was 67 and the radiolunate angle 0. dorsal intercalated segment instability ( disi ) deformity was not observed , although there was flexion of the scaphoid and a break in arc ii of gilula s line at neutral and ulnar deviationfig . 
4magnetic resonance imaging at the 1-year follow - up showing no evidence of avascular necrosis of the scaphoid and lunate radiographs at initial diagnosis showing palmar - divergent dislocation of the scaphoid and lunate postoperative radiographs showing good alignment of the carpal bones .
the scapholunate angle was 54 and the radiolunate angle 6. gilula s line was well - regulated radiographs at the 1-year follow - up .
the scapholunate angle was 67 and the radiolunate angle 0. dorsal intercalated segment instability ( disi ) deformity was not observed , although there was flexion of the scaphoid and a break in arc ii of gilula s line at neutral and ulnar deviation magnetic resonance imaging at the 1-year follow - up showing no evidence of avascular necrosis of the scaphoid and lunate the patient provided written informed consent prior to inclusion in this study , which was authorized by the local ethics committee and performed in accordance with the ethical standards of the 1964 declaration of helsinki as revised in 2000 .
as palmar - divergent dislocation of the scaphoid and lunate is rare , its optimal treatment remains unclear . in previous reports ,
two patients were treated by open reduction and cast immobilization [ 1 , 2 ] , two by open reduction and percutaneous pinning of the carpal bones and cast immobilization [ 3 , 4 ] , one by open reduction and suture of the anterior capsule and cast immobilization , and one by proximal row carpectomy ( prc ) ( table  1 ) .
carpal instability is severe in divergent dislocation due to ruptures of both the scapholunate and lunotriquetral ligaments .
therefore , it is difficult to stabilize the carpal bones and still retain sufficient wrist motion.table  1review of previous patients with divergent dislocation of the scaphoid and lunateauthorfollow - up ( months)surgical procedureapproachimmobilization ( duration)k - wire removalrange of motioncomplicationscampbell 12only open reductionpalmarcastnr 
ext 1/2flex 1/3 of healthy sidenonegordon 12only open reductionpalmarcast4  weeks  ext 15flex 25disikupfer 42open reduction k - wire pinning ( s - l)palmar & dorsalcast4  months4  monthsext 25flex 0crps disi an ( scaphoid , lunate)baulot 42open reduction anterior capsule suturepalmarcast6  weeksalmost fulldisikang 18open reduction k - wire pinning ( s - l / s - c)palmarcast6  weeks6  weeksalmost fullnonedomeshek 1proximal row carpectomypalmar & dorsalsplint1  month  nrnran avascular necrosis , nr not recorded , k - wire kirschner wire , s scaphoid , l lunate , t triquetrum , c capitate , disi dorsal intercalated segment instability , crps complex regional pain syndrome , ext extension , flex flexion review of previous patients with divergent dislocation of the scaphoid and lunate an avascular necrosis , nr not recorded , k - wire kirschner wire , s scaphoid , l lunate , t triquetrum , c capitate , disi dorsal intercalated segment instability , crps complex regional pain syndrome , ext extension , flex flexion among the methods recommended to repair , the anterior and posterior ligaments on both sides of the lunate are combined palmar and dorsal approaches , and open reduction and percutaneous pinning of the scapholunate and scaphocapitate joints without suture of the interosseous ligaments .
although we found that suturing of the dorsal scapholunate and lunotriquetral ligaments provided a satisfactory outcome in our patient , wrist stiffness , carpal malalignment due to a break in arc ii of gilula s line between the lunate and triquetrum , and flexion of the scaphoid still remained .
first , we should have sutured the palmar , not the dorsal , lunotriquetral ligament because the palmar ligament is stronger .
moreover , in addition to fixing the scapholunate and lunotriquetral joints with kirschner wires , we should have fixed the scaphocapitate joint to maximize anatomical carpal alignment .
thus , for reliable carpal stability , we recommend ligament repair and temporary joint fixation of the carpal bones .
subsequent wrist stiffness may be prevented by early removal of kirschner wires after surgery and starting wrist exercises .
indeed , it may be possible to remove kirschner wires earlier than 6 weeks when interosseous ligaments are sutured . the injury to our patient
prc on a patient with a scapholunate dislocation and complete scaphoid extrusion resulted in a good clinical outcome , suggesting that prc may eliminate avascular necrosis and avoid additional surgery in patients with this type of injury .
however , although prc has shown satisfactory clinical outcomes , postoperative rom and grip strength averaged 5070% and 6090% , respectively , compared with the healthy side , outcomes similar to those observed in our patient .
therefore , except when unavoidable , we recommend surgical repair , especially for active young people and manual workers , with prc considered a salvage procedure .
 we describe a patient with palmar - divergent dislocation of the scaphoid and lunate . 
 after successful closed reduction , the scapholunate and lunotriquetral ligaments were sutured through the dorsal approach , and the anterior capsule was sutured through the palmar approach . 
 the scapholunate and lunotriquetral joints were fixed with kirschner wires for 7 weeks . at the 1-year follow - up , 
 magnetic resonance imaging showed no evidence of avascular necrosis of the scaphoid or lunate , and radiographs showed no evidence of the dorsal and volar intercalated segment instability patterns associated with carpal instability . however , flexion of the scaphoid and a break in gilula s line remained . to our knowledge , this is the first report showing treatment of palmar - divergent dislocation of the scaphoid and lunate by suturing the carpal interosseous ligaments . 