One stage uncemented revision of infected total hip replacement using cancellous allograft bone impregnated with antibiotics.

Infection of a total hip replacement (THR) requires component removal and thorough local debridement. Usually, long-term antibiotic treatment in conjunction with a two-stage revision is required. This may take several months. One-stage revision using antibiotic-loaded cement has not gained widespread use, although the clinical and economic advantages are obvious. Allograft bone may be impregnated with high levels of antibiotics, and in revision of infected THR, act as a carrier providing a sustained high local concentration. We performed 37 one-stage revision of infected THRs, without the use of cement. There were three hips which required further revision because of recurrent infection, the remaining 34 hips (92%) stayed free from infection and stable at a mean follow-up of 4.4 years (2 to 8). No adverse effects were identified. Incorporation of bone graft was comparable with unimpregnated grafts. Antibiotic-impregnated allograft bone may enable reconstruction of bone stock, insertion of an uncemented implant and control of infection in a single operation in revision THR for infection.

A physical, chemical, and mechanical study of lumbar vertebrae from normal, ovariectomized, and nandrolone decanoate-treated cynomolgus monkeys (Macaca fascicularis).

Ovariectomized cynomolgus monkeys have previously been investigated as a nonhuman primate model of postmenopausal osteoporosis (Jerome et al., Bone Miner 9:527-540; 1994). In the present study, Fourier transform infrared microspectroscopy (FTIRM) was used to verify that differences in bone mineral quality and quantity in the vertebrae of mature intact (INT) and ovariectomized (ovx) monkeys were analogous to those seen in osteoporotic and nondiseased human bones. FTIRM spectra were acquired from 15 trabeculae per vertebra from three ovx and three INT adult monkeys (mean age 8 years). These spectra were compared with those of both trabecular and previously reported osteonal bone obtained from 3 "normal" and 11 postmenopausal osteoporotic human subjects. While variations in the mineral:matrix ratio (mineral content), carbonate:phosphate ratio, and crystallinity are typical for trabecular bone from iliac crests of normal human subjects, the values of these parameters were relatively static for trabecular bone from postmenopausal osteoporotic human subjects. In general, trabecular bone from postmenopausal osteoporotic human subjects exhibited decreased mineral content (1.0 +/- 0.5 vs. 2.9 +/- 0.6), increased crystallinity, and increased carbonate:phosphate relative to controls. Similarly, trabecular bone from ovariectomized monkeys exhibited lower mineral content (5.8 +/- 0.2) compared with the INT group (6.2 +/- 0.2; p

The hip joint as a conchoid shape.

The hip joint is not an exact ball and socket joint. In a meridian section, the mean deviation from a conchoid shape is quite small, so that this shape might better describe the joint's shape. This conclusion was reached by measuring the cartilaginous and osseous shapes of eight normal hip joints (multiorgan donors with average of age 33 yr, range 19-46 yr) using a CNC coordinate measuring machine (CMM). On two additional hip joints, only the osseous shape was determined. A rotational axis was first determined by finding parallels of latitude at the femoral head and acetabulum. At the meridian sections, the best-fitting circle or conchoid was determined from the scanned measuring points, using least-squares regression. Two perpendicular meridians were then measured for each sample and used to evaluate the three-dimensional shape. The medium squared deviation showed a better fit for a conchoid shape compared to a sphere for all samples tested. Furthermore, the equation of the conchoid for the femoral head (r = a + b cos phi) and that for the acetabulum (r' = a' + b' cos phi) were related in that a = b' and b = a' within mean deviation factors of 4%. Their special shape makes the joint less likely to sublux compared to a ball and socket joint. In addition, the rolling and gliding mechanisms between the two shapes may result in less wear.

[Results of isolated lateral retinaculum release as a treatment method in patello-femoral dysfunction]. / Ergebnisse der isolierten lateralen Retinaculumspaltung als Behandlungsmethode bei patellofemoraler Dysfunktion.

The results of lateral retinaculum-release by arthroscopic, subcutaneous and open technique on 122 patients are presented. Within a follow-up period of 3.68 years in average the postoperative success rate was 56%. The results of surgery if the cartilage of the patella was unchanged--as well as with isolated medial or lateral chondromalacia--were good. If there was medial and lateral chondromalacia the isolated retinaculum-release is insufficient. The rate of postoperative complications (effusion, haemorrhage) by arthroscopic surgery technique is with 11.1% distinctly above the results by the subcutaneous technique, which amounts to a mere 3%. The 30 degrees degree-tangential x-ray technique combined with external rotation of the lower leg and simultaneous tension of the quadriceps gives much better information of the position of the patella than the 30 degrees degree x-ray without quadriceps tension.

[Follow-up analysis of total hip endoprosthesis after femoral neck fracture with and without previous operation]. / Verlaufsanalyse von Hüfttotalendoprothesen bei Zustand nach Schenkelhalsfraktur mit und ohne Voroperation.

Damage occurring after joint-preserving surgical treatment of femoral neck--mostly femoral head necrosis of pseudoarthrosis-necessitates endoprosthetic joint replacement. In the case of inferior bone quality and unfavorable fracture forms as well as after failed conservative therapy, surgical treatment consists of implanting a total hip endoprosthesis. Between 1971 and 1989, 120 patients received total hip replacement after suffering fractures of the femoral neck: 61 patients did not have previous surgery, 59 patients had had joint-preserving surgery. Statistical analysis of the results showed that the primary stabilizing operation to preserve the joint did not have a negative influence on the survival probability of the total hip replacement in comparison with primary implantation. If the joint-preserving primary intervention fails, total hip replacement is a good choice for secondary surgery. In the case of complications such as femoral head necrosis or pseudoarthrosis the indication for total hip replacement should therefore be made early on.

[The kinetostatics of ligament operations on the knee joint--exemplified by tractopexy]. / Die Kinetostatik von Bandoperationen am Kniegelenk--dargestellt an der Traktopexie.

If the iliotibial band should have a satisfactory function in order to improve suture or replacement of the anterior cruciate ligament the best point of fixation for tractopexy is the slope from the lateral femoral condyle to the femoral shaft in its dorsal third. In addition the position of the knee joint at the time of fixation is of importance. The angle should theoretically be 43 degrees.