Purpose: The purpose of this study is to investigate the external and internal vascular anatomy of the lunate bone. The genesis of lunatomalacia requires some combination of load, vascular risk and mechanical predisposition. The findings will be correlated with the major existing theories of the cause of lunatomalacia and the most frequent fractures associated with Kienbocks disease: transverse shear fracture and midcoronal fracture.

Material and methods: We studied 21 cadaver upper limbs using latex injection and Spalteholz technique. We investigated the extra- and intraosseous blood supply. In 17 wrists we evaluate the incidence and distribution of anatomic features, arthrosis, and soft tissue lesions.

Results: The lunate morphology was 5 Type I (29.4%), 11 Type II (64.7%) and 1 Type III (5.9%). The lunate was found to have a separate facet for the hamate in 47.1% (Size 3–6 mm). Most frequent arthrosis was identified in the radius (88.2%) and lunate (94.1%). The triangular fibrocartilage complex (TFCC) was found torn in 47%, the lunotriquetral interosseous ligament (LTIL) was torn in 23.5%, and the scapholunate interosseous ligament (SLIL) was torn in 53% of the wrists. Statistical analysis found a correlation between the presence of arthrosis at the proximal pole of the hamate and the presence of a lunate facet. There was also a correlation between the presence of a tear in the SLIL and the presence of cartilage erosion in the scaphoid (p= 0.002). Arthrosis on the lunate was found to have a correlation with an SLIL tear or TFCC tear. The nutrient vessels entered the lunate throught the dorsal and volar poles in all the specimens. Dorsal vessels enter the bone through one or two foramina in the proximal, ulnar, and nonarticular aspect of the bone. Two to six nutrient vessels were observed entering the volar pole throught a ligament insertion: radioscapholunate ligament of Testut-Kuentz, radio-lunate-triquetrum ligament and ulnar-lunate-triquetrum ligament.

Conclusions: The lunate had consistent dorsal and palmar arteries entering the bone in all the specimens. The supply blood and foramina number is more important in the volar pole of the lunate than the dorsal pole. The vascular patterns support a theory of compression fracture from repeated trauma, or anatomical predispositions as the most likely cause of Kienbocks disease.

Introduction: Synovial sarcoma ranks as the fourth most common sarcoma, but it is uncommon in the hand. Most Synovial Sarcomas arise in para-articular soft tissue such as tendon, tendon sheath and bursa adjacent to the large joints capsules. Arround 60–70% of these tumors involve lower extremity and they frequently affect knee, thigh and foot. The reported incidence for Synovial Sarcoma in hand is only 8.5%.

Material and methods: We carried out a retrospective study of 6 hand and forearm sarcomas, of a series of 35 synovial sarcomas surgically treated in our center from 1991 to 1997, with a 6 years follow up (3y.–11y.). 3 patients were male and 3 female, with a mean age of 54 years at the moment of initial diagnosis. Histologically all of them were synovial sarcomas: 4 monophasic and 2 biphasic. The inmunochemistry showed that the neoplasic cells were positive for vimentin, epithelial membrane antigen and cytokeratin. 2 of them were localized in the palmar aspect of the hand (2 ulnar cases and 2 eminence tenar cases), an 2 cases were dorsal. 2 cases were misdiagnosed as benign lesions and treated with tumor excision at another center.

Results: Primary treatment consisted of radical local excision of synovial sarcoma of the hand. 5 patients received adjuvant chemotherapy with CYVADIC and radiotherapy. 2 cases of recurrence received a second surgical treatment with forearm amputation. The mean time to recurrence was 12 months. At the end of the follow-up 3 patients developed metastatic disease and 2 of them died.

Discussion: Synovial Sarcoma in hand is a highly malignant tumor; due to its morphology they can be misdiagnosed as benign lesions such as aggressive fibromatosis or ganglion cysts. If we diagnose a soft tissue tumor in hand we must practice complementary tests to achieve early diagnosis. It is also important the multidisciplinary treatment of Synovial Sarcoma.

Aims: Analyze the long-term survival of cementless meniscal bearing total knee arthroplasty (TKA). Methods: Two hundred and thirty-two consecutive cementless primary meniscal bearing Low Contact Stress TKA were performed on 203 patients in our institution from November 1988 to June 1996. The diagnosis was osteoarthritis in 192 knees (83%) and rheumatoid arthritis in 40 cases (17%). Mean age at surgery was 66.5 years (range:16–90). Cruciate retaining prosthesis was implanted in 81% and a cruciate sacrificing prosthesis in 19%. Twenty patients died and ten patients (4,3%) were lost to follow-up. The remaining 202 knees (87%) had an average follow-up of 116.7 months (range:70–165). Survival analysis was done using as end point revision surgery or recommended revision. Results: Twenty-six TKAs (11.2%) required revision: infection (3), patelar failure (2), tibial/femoral loosening (2) and polyethylene failure (19). Age, gender, diagnosis and sacrificing cruciate ligaments were not related with prosthesis failure (p> 0.05). The Kaplan-Meier survival analysis showed a mean of 155 months (95%CI:150–159). The life table survival estimate at 10 years was 90.4% (85–95). The cumulative survival rate for patellar failure was 99% (98–100), for mechanical loosening 99% (98–100) and 91.3% (87–96) for polyethylene failure. The Log Rank Test was significant for poliethylene failure (p=0.0005). Conclusions: In our experience overall long-term survival of cementless meniscal bearing TKAwas acceptable. Mobile bearing knee prosthesis satisfactorily resolved problems related with patellar failure or tibial/femoral loosening. Polyethylene failure continues to be the main problem in long-term survival of knee prosthesis.