Unusual mechanical complications of unicompartmental low contact stress mobile bearing patellofemoral arthroplasty: a cause for concern?

The Low Contact Stress Patellofemoral Arthroplasty (LCS PFA) is a newer design belonging to the second generation of inlay type implants, addressing the problems encountered in the first generation models (Lubinus & Richard's). The cemented mobile bearing metal backed patellar component in this system is "modular"; allowing interchangeable usage with either the trochlear component in a PFA or the femoral component of a total knee arthroplasty, thus obviating the need for patellar revision during conversion of PFA to TKA. The younger active patient with a PFA may exert extreme joint reaction forces on their patellar implant, rendering early loosening of the patellar implant. The endurance of this implant with repeated flexion beyond 90 degrees is also a concern. We describe a series of three unusual mechanical failures associated with this particular design of metal backed patellar component of the unicompartmental LCS patellofemoral arthroplasty.

Bilateral gas gangrene of the hand - a unique case.

Gas gangrene is a rare and rapidly progressive process with the propensity for devastating consequences. We report the first case of bilateral gas gangrene of the hand following bilateral middle phalangectomy of the middle fingers.

Unusual limb injury associated with sport parachuting.

The case is reported of an open injury of the right arm sustained during a parachute jump. The fracture was managed in the usual way with wound debridement, wound irrigation, skeletal stabilisation, and reconstruction of the soft tissues. Good shoulder and elbow function were achieved. The combined effort of an orthopaedic trauma surgeon and plastic surgeon is essential to improve outcomes in such cases.

Radial nerve palsy in an elite bodybuilder.

A case is reported of high radial nerve palsy in an elite bodybuilder caused by an extrinsic mass effect of muscular hypertrophy. Surgical decompression resulted in complete clinical resolution.

Delay in diagnosis of slipped upper femoral epiphysis.

Treatment of slipped upper femoral epiphysis (SUFE) is directed at preventing progressive slippage, minimizing deformity and avoiding avascular necrosis and chondrolysis. Delay in treatment adversely affects long-term outcomes. In a retrospective study we assessed delays between symptom onset and evaluation of the patient in an orthopaedic department. 27 patients aged 10-16 years were grouped by source of referral (general practitioner or accident and emergency department), and hips were classified as stable or unstable according to ability to bear weight. The 27 children had 37 affected hips, 31 stable and 6 unstable. In the 20 patients referred by general practitioners, mean delay from symptom onset to orthopaedic evaluation was 119 days (range 2-504); in the 7 referred from accident and emergency departments it was 95 days (1-482). In the latter group the slips were more likely to be acute and unstable. 9 (45%) of the patients in the general-practitioner group had hip radiography before referral, all correctly diagnosed though not all the examinations included the recommended frog-lateral views. Long delays between onset and diagnosis of SUFE are most likely in patients with mild symptoms, able to bear weight on the hip. Any adolescent with undiagnosed hip or knee pain that has lasted more than a week should undergo radiological investigation of the hip, with frog-lateral as well as anteroposterior views.

Percutaneous manipulation of an osteoarthritic hip for femoral nailing.

An increasing number of elderly patients with femoral shaft fractures also have coexisting osteoarthritis of the hip. This proves to be difficult both in fracture reduction [1] and localisation of the point of entry into the piriform fossa. To facilitate guide wire entry in a patient with osteoarthritis of the hip, considerable adduction of the hip may be required during conventional closed antegrade femoral nailing. We describe a technique using a Steinman pin on a T-clamp to facilitate localisation of the piriform fossa.

Bollen's jig and anterior cruciate ligament reconstruction.

We report the design of a surgical instrument that facilitates the harvest of the autologous patellar tendon in anterior cruciate ligament (ACL) reconstruction. The advantage of this jig is that it is a simple, self-centring device resulting in a reproducible and consistent autograft. Its use also minimises the potential risks of donor site morbidity such as patellar fracture and tendon rupture. We briefly describe our technique and discuss its advantages.

Plastic surgery and pseudoxanthoma elasticum.

Pseudoxanthoma elasticum is a cause of abnormal skin laxity. A case of lower face and neck skin laxity is presented with its treatment by cutaneous rhytidectomy.

Cutaneous malignant melanoma in teenagers.

Of 57 reviewed cases of malignant melanoma in teenagers, 51 had a minimum follow-up of 5 years. The histological and some clinical features of the 51 cases were compared for diagnostic and prognostic significance with those of 19 Spitz naevi and 10 other benign naevi using the SPSS-X computer program. The overall crude survival was 71% (males 64%, females 81%). Five patients with regional metastases survived more than 5 years, three of these more than 10 years. The main statistically significant features associated with a poor prognosis were Breslow thickness, diameter of ulcer, abnormal mitoses, pushing dermal borders and marginal (deep) mitoses. In comparison with Spitz naevi, features favouring malignancy were Breslow thickness, fine dusty cytoplasmic melanin pigment, marginal or abnormal mitoses, epithelioid intra-epidermal melanocytes below parakeratosis, dermal nests larger than junctional nests and the mitotic rate in the papillary dermis. Features favouring a benign lesion were diffuse maturation, spindle cells, spindle nuclei and Kamino bodies, especially if numerous or clustered. In comparison with the atypical benign naevi, significant features favouring malignancy were marginal or abnormal mitoses, single cell epidermal invasion below parakeratosis, large nuclei and irregular nuclei.

Malignant melanoma in childhood: a clinicopathologic study of 13 cases and comparison with Spitz nevi.

The clinical and histological features of 13 malignant melanomas in children less than 13 years of age in New South Wales, Australia, were compared with those in a control group of children with 15 Spitz nevi, 4 of which were considered atypical, and 2 unusual compound nevocellular nevi. Six of the controls had been previously diagnosed histologically as malignant melanoma. The objective observations made by one or more histopathologists experienced in reporting melanocytic lesions, and the clinical details, mainly from the Sydney Melanoma Unit files, were entered on a detailed protocol. Evaluation was assisted by the use of SPSS-X software on a mainframe VAX computer. Six of the 13 children with malignant melanoma died with their disease. The most frequent clinical features found in the malignant melanomas were bleeding, ulceration, itching, and black or variegated color. Recent enlargement and darkening were noted in the majority of both the malignant melanomas and the Spitz nevi. Histological features favoring malignancy in this series were mitoses within 0.25 mm of the dermal margin of the melanoma, a dermal mitotic rate exceeding 2/mm2, ulceration, surface exudate, large pigment granules, and clear-cell differentiation. The median thickness of the malignant melanomas was 1.3 mm but in the 4 children who died with melanoma the median thickness was 2.9 mm. Absence of mitoses, predominance of spindle cells, and diffuse maturation favored Spitz nevus. The median thickness of the Spitz nevi was 0.7 mm.

Recovery of human fetal pancreas after one year of implantation in the diabetic patient.

Between one and six cultured human fetal pancreata were allografted into five insulin-dependent diabetic recipients and their progress monitored for a year on each occasion. To prevent rejection the tissue was cultured for 1-3 weeks before transplantation, the HLA-DR antigens of the donor tissue were matched with those of the recipient when a single pancreas was used, and four of the recipients were immunosuppressed, three because of coexisting renal grafts. Graft function was observed transiently in one of the recipients. In three others human fetal pancreas was recovered 9-14 months after transplantation, although it was being slowly rejected during this time. Beta cells were present in the graft but did not function adequately to enable immunoreactive C-peptide to be measured in peripheral blood. The issues of rejection and immaturity of the human fetal pancreas will need to be surmounted if the potential of the human fetal pancreas to normalize blood glucose levels in diabetic man is ever to be realized.

Metastatic adeno or undifferentiated carcinoma from an unknown primary site--natural history and guidelines for identification of treatable subsets.

Two hundred and eighty-six patients presenting with metastatic adenocarcinoma or undifferentiated carcinoma whose primary site was not identified by clinical history, physical examination and chest radiograph have been studied. Median survival from presentation was 22 weeks. Factors independently predicting improved survival were lymph node presentations, good performance status and body weight loss of less than 10 per cent. In 88 (31 per cent) patients the primary tumour site was subsequently identified, in 58 (20 per cent) during life. Lung cancer was the most frequently identified primary tumour, and in only 32 (11 per cent) of the patients was a 'treatable' primary tumour (i.e. germ cell, breast, ovarian, prostate, thyroid cancer or lymphoma) identified. Among the treatable primary tumours were those in eight out of 16 female patients presenting with axillary metastases who were subsequently shown to have primary breast cancer and four of 13 females presenting with ascites who were found to have primary ovarian cancer. Prostatic cancer was confirmed in five out of 13 men with raised serum acid phosphatase. Of 22 patients with elevated serum alphafoetoprotein (AFP) or beta-human chorionic gonadotrophin levels (beta HCG) 18 had some features of the 'atypical teratoma syndrome'. Of the total of 32 patients with treatable tumour types, 29 (90 per cent) were identified during life. Median survival for patients with treatable tumour types identified during life was 104 weeks, compared with 22 weeks for the group as a whole. Retrospective immunocytochemical staining of the original biopsy showed that prostatic specific antigen and antibodies to beta HCG and AFP were diagnostically useful, but a series of organ site non-specific markers of histogenesis or cellular differentiation (carcinoembryonic antigen, secretory component for IgA, peanut lectin binding, epithelial membrane antigen and keratin) showed no significant correlations with identified primary sites, responsiveness to empirical chemotherapy or survival. Metastatic undifferentiated carcinoma or adenocarcinoma from an unknown primary site represents 6.5 per cent of all referrals to the medical oncology unit, Royal Prince Alfred Hospital, Sydney. We offer guidelines for the rapid identification of the limited number of primary sites for which effective and specific forms of systemic treatment are available.

Long-term survival of human fetal pancreatic tissue transplanted into an insulin-dependent diabetic patient.

The explants of two human fetal pancreases of 15 weeks gestational age were cultured for 6-7 days before being implanted in a 29-year-old insulin-dependent diabetic woman who had received a renal graft two months previously. One pancreas was placed in the flexor muscles of the forearm whilst the other was implanted in an omental pouch. To reduce the chances of rejection the tissue was cultured in vitro, the donor of the tissue placed in the forearm was DR antigen matched with the recipient and the patient remained on cyclosporin and prednisone therapy. At 3 months a mass developed in the forearm muscle at the site of transplantation, and continued to grow. Biopsy at 13 months showed a small area of original pancreas surrounded by a large collection of mature lymphocytes and fibrous tissue. A and D cells could be seen around pancreatic ducts but B cells and acinar tissue were absent. At no stage during follow-up was plasma C-peptide detected in the recipient.

Histologic differentiation of human fetal pancreatic explants transplanted into nude mice.

The transplantation of human fetal pancreas has been suggested as a means of treatment of insulin-dependent diabetes in man. We have obtained human fetal pancreata during the second trimester of pregnancy and transplanted 1-mm3 explants subcutaneously (s.c.) into both diabetic and nondiabetic nude mice, some of the tissue being cultured in vitro before implantation. These implants coalesced and grew. They were removed at intervals up to 37 wk later and showed selective differentiation of endocrine tissue that normally occurs in the fetus and neonate, with formation of bipolar, mantle, and mature islets. There was growth of this endocrine tissue with significantly more islets than in the freshly stained fetal pancreas assuming an average dimension larger than 150 micron, which is the reported mean diameter of a neonatal islet. Duct and fibrous tissue remained viable, but there was no definitive acinar tissue seen. The pancreata uncultured before implantation reached a larger size than that attained by those implants cultured before being transplanted, the difference probably being the amount of ductular and mesenchymal tissue still present. Of those glands cultured before transplantation, the longer the period of culture, the smaller the size the implants reached. Culture beyond 3 wk in vitro made it difficult to macroscopically locate the implant. These data show that, in human fetal pancreas removed from its usual environment, both selective differentiation of the endocrine component and growth of the islets can occur.