Dual mobility acetabular component in revision total hip arthroplasty for persistent dislocation: no dislocations in 50 hips after 1-5 years.

BACKGROUND: A dual mobility cup has the theoretic potential to improve stability in primary total hip arthroplasty (THA) and mid-term cohort results are favorable. We hypothesized that use of a new-generation dual mobility cup in revision arthroplasty prevents dislocation in patients with a history of recurrent dislocation of the THA. MATERIALS AND METHODS: We performed a retrospective cohort study of patients receiving an isolated acetabular revision with a dual mobility cup for recurrent dislocation of the prosthesis with a minimum follow-up of 1 year. Kaplan-Meier survival analyses were performed with dislocation as a primary endpoint and re-revision for any reason as a secondary endpoint. RESULTS: Forty-nine consecutive patients (50 hips) were included; none of the patients was lost to follow-up. The median follow-up was 29 months (range 12-66 months). Two patients died from unrelated causes. Survival after 56 months was 100 % based on dislocation and 93 % (95 % CI 79-98 %) based on re-revision for any reason. Radiologic analysis revealed no osteolysis or radiolucent lines around the acetabular component during the follow-up period. CONCLUSION: The dual mobility cup is an efficient solution for instability of THA with a favorable implant survival at 56 months. LEVEL OF EVIDENCE: Level 4, retrospective case series.

Radiographic measurement of the distal tibiofibular syndesmosis has limited use.

Radiographs of 20 plastinated human cadaveric lower legs were obtained in 12 positions of rotation to determine the optimal parameter for reliable assessment of syndesmotic and ankle integrity, and to assess the effect of positioning of the ankle on this parameter. Three observers measured eight parameters twice after four repetitions of ankle positioning. Intraclass correlation coefficients and reproducibility were assessed. Some tibiofibular overlap was present in all radiographs in any position of rotation. The medial clear space was smaller than or equal to the superior clear space in all radiographs. Intraclass correlation coefficients of the other parameters were too weak for reliable quantitative measurements, as was shown with a mixed model analysis of variance. This resulted from the inability to reproduce ankle positioning, even under optimal laboratory circumstances. This study shows that no optimal radiographic parameter exists to assess syndesmotic integrity. Tibiofibular overlap and medial and superior clear space are the most useful, because one-sided traumatic absence of tibiofibular overlap may be an indication of syndesmotic injury, and a medial clear space larger than a superior clear space is indicative of deltoid injury. Additional quantitative measurement of all syndesmotic parameters with repeated radiographs of the ankle cannot be done reliably and therefore are of little value.

The influence of ankle positioning on the radiography of the distal tibial tubercles.

Three embalmed human lower legs, with the anterior and posterior tubercles of the distal tibia marked with needles, were radiographed in four positions of rotation to describe the projection and the configuration of the distal tibial tubercles and the tibiofibular syndesmosis, since the distal tibial tubercles are often described incorrectly in the literature. The anterior and posterior tubercles have distinct features that can be recognized in different positions of rotation. The anterior tubercle has an angular shape with its maximum dimension approximately 1 cm above the joint line. The posterior tubercle is a rounded structure in continuity with the posterior lip of the tibia, projecting caudally from the anterior tubercle superimposed on the talus. It was shown that the tibiofibular clear space (TFCS) and the tibiofibular overlap (TFO) differ considerably with rotation and that neither the TFCS nor the TFO depicts a constant syndesmotic interval. Both change considerably with varying rotational projections. To achieve uniformity it is recommended that the TFCS be measured as the distance between the medial border of the fibula and the floor of the incisura, and the TFO as the distance between medial border of the fibula and the anterior tubercle, both on the anteroposterior radiograph.

Use of human GH in elderly patients with accidental hip fracture.

OBJECTIVE: To investigate whether early intervention with recombinant human growth hormone (hGH) after hip fracture improves functional recovery and long-term outcome. SUBJECTS AND METHODS: Functional recovery after hip fracture is often incomplete. The catabolic situation that develops after the hip fracture accident, and a state of malnutrition either pre-existing or developing after surgery, are main contributing factors for the poor clinical outcome. hGH has been used to promote anabolism in a variety of clinical catabolic situations. The study design was randomized, double-blind and placebo-controlled. A total of 111 patients older than 60 years with an accidental hip fracture (mean age 78.5+/-9.1 (s.d.) years) were randomized to receive either hGH (20 microg/kg per day) or placebo for a period of 6 weeks, starting within 24 h after the hip fracture accident. Thereafter patients were followed up for an additional period of 18 weeks. Efficacy was assessed by comparing the changes in the Barthel Index score of activities of daily living and in a patient's living situation between the hGH- and the placebo-treated subjects. RESULTS: Eighty-five (78.5%) patients completed the first 8 weeks of the study and 76 (68.5%) the entire study period of 24 weeks. When split according to age, a trend was found that for patients older than 75 years the changes in Barthel Index score from baseline were less in the hGH group than in the placebo group (-18.6+/-18 vs -28.1+/-26) at 6 weeks after surgery (P<0.075). There was an overall trend to a higher rate of return to the pre-fracture independent living situation in the hGH group than in the placebo group. Analysis by age revealed a significantly higher proportion of hGH- than placebo-treated patients returning to the pre-fracture living situation for subjects older than 75 years (93.8 vs 75.0%, P=0.034). hGH treatment increased IGF-I values to levels in the range of those of normal subjects of 50-60 years of age. CONCLUSIONS: A 6 week treatment with hGH (20 microg/kg per day) of otherwise healthy patients after an accidental hip fracture may be of benefit if given to subjects older than 75 years of age. The rate of return to the pre-fracture living situation in subjects of this age treated with hGH was significantly increased when compared with the placebo-treated group. The treatment intervention was well tolerated and no safety issues were recorded.

The straight line graph in limb length inequality. A new design based on 182 Dutch children.

Moseley's Straight Line Graph (M-SLG), which is based on growth data obtained in the 1940s and 1950s, is helpful for the timing of physiodesis. We investigated whether current growth data could improve this graph. We estimated growth curves based on recent data on 182 Dutch children, collected between 1979 and 1994, using repeated measure analysis of variance. In both boys and girls, the mean femur and tibia length had increased, when compared to the data collected by Anderson et al. (1964). Based on our growth data, a new straight line graph (Rotterdam Straight Line Graph; R-SLG) was created. Its value was assessed by comparing the difference between the predicted length of the short (i.e., not operated) limb at maturity with the final limb length. In a group of 34 children who underwent physiodesis up to 10 years ago, the R-SLG gave better prediction of limb length at maturity than the M-SLG did in 22 of 34 cases and equal results were obtained in 5 cases. We conclude that our updated SLG can improve the prediction of final limb length and thus also the timing of physiodesis.

Measurement of limb length inequality. Comparison of clinical methods with orthoradiography in 190 children.

We studied the agreement in measuring limb length inequality with orthoradiograms and clinical methods. In 190 children attending our Limb Length Clinic for the first time, 95% of the measurements with wooden boards was within -1.4 and +1.6 cm of the results of the orthoradiograms. A tape measure had significantly less agreement. The predictive value of a localization of the main limb length inequality above the knee, as found with a tape measure, was 64% and for a localization of the main limb length inequality below the knee 75%. A Wooden Board Reliability Graph is presented, which can be helpful in the decision to perform orthoradiographic measurements of limb length inequality in, e.g., evaluation of impairment.

Prospective comparison of hip fracture treatment. 856 cases followed for 4 months in The Netherlands and Sweden.

In a prospective multicenter study 1115 hip fracture patients were registered in Rotterdam (The Netherlands), Sundsvall and Lund (Sweden). The patients had similar background parameters with a mean age of 78 years, about half of them living alone and just above 80 percent coming from independent living. For cervical fracture, hemiarthroplasty was the predominating treatment in Rotterdam (n 169), whereas osteosynthesis was used in Sundsvall (screws n 135) and Lund (hook-pins n 148). The mean (median) hospitalization time was 32 (20) days in Rotterdam, 16 (12) days in Sundsvall, and 17 (10) days in Lund. Discharge to independent living varied from 53 percent in Lund to 72 percent in Sundsvall. Functional outcome (walking ability and ADL capacity) was at 4 months similar in all groups, but at 2 weeks was lower in Rotterdam. Mortality at 2 weeks/1 month/4 months was in Rotterdam 4/9/20, in Sundsvall 2/4/13, and in Lund 0/3/10 percent. Trochanteric fractures were treated by screwplate in Rotterdam (n 146) and Lund (n 78), and by Ender nails in Sundsvall (n 117). The mean (median) hospitalization time was in Rotterdam 39 (29) days, in Sundsvall 24 (15) days and in Lund 19 (11) days. Discharge to independent living varied from 41 percent in Lund to 57 percent in Sundsvall. Functional outcome was similar between the groups. Mortality at 2 weeks/1 month/4 months was in Rotterdam 2/6/14, in Sundsvall 6/12/19 and in Lund 12/12/18 percent. Thus, our study has shown that it is possible to perform a prospective multicenter study involving different European countries.(ABSTRACT TRUNCATED AT 250 WORDS)

Distal femoral physiolysis in renal osteodystrophy. Successful nonoperative treatment of 3 cases followed for 5 years.

Slippage of 5 distal femoral epiphyses in 3 children with renal osteodystrophy was successfully treated without operation. During optimal medical treatment and plaster immobilization of the knee, remodelling took place by reorientation of the growth plate.

Timing of physiodesis in limb length inequality. The Straight Line Graph applied in 30 patients.

In a prospective study 30 children underwent 33 physiodeses for lower limb length inequality (LLI). Timing of surgery was based on (bi)annual orthoradiographic measurements and skeletal age, and in accordance with Moseley's Straight Line Graph. The mean predicted LLI was 5.2 (3.0-11) cm and the mean LLI at the end of growth was 1.4 (0.0-4.3) cm. In 9 patients final LLI exceeded 1.5 cm, and one of these patients was operated on twice. In total, secondary operations were performed three times. After analysis of the failures it is concluded that the accuracy of the Straight Line Graph is mainly limited by the pattern of skeletal maturation. Recommendations to prevent failures from other causes are given.

Reconstruction of the tibia by dual grafting. 3 cases of tumor resection.

Large defects of the tibia can be bridged with autologous cancellous grafts between the remaining fibula and a contralateral tibial cortical graft. The long-term results of this technique in 3 cases after resection of a malignant tumor were either excellent or fair. It is concluded that this technique is an effective limb-saving surgical procedure.

Prevention of thrombosis after hip arthroplasty. A prospective study of preoperative oral anticoagulants.

A prospective randomized study involving 101 patients undergoing total hip replacement was performed to find out whether prophylactic anticoagulation starting 4 days before the operation was more effective than starting on the eve of the operation. The postoperative level of anticoagulation was set at an INR of 2.1. There was no difference between the two groups in the incidence of proximal localized deep venous thrombosis. Blood loss did not depend on the level of peroperative anticoagulation. There were no postoperative hemorrhagic complications. No fatal pulmonary embolism occurred during the study. After discontinuation of the oral anticoagulants because of a negative venogram, nonfatal pulmonary embolism occurred in 3 out of 55 patients. A plea is made for low-dose anticoagulation for 3 months after total hip arthroplasty.

Oral anticoagulants and dextran for prevention of venous thrombosis in orthopaedics.

A hundred and fifty-two patients who were to undergo major orthopaedic surgery were divided into two groups in order to study the value of dextrans administered as adjuvants to oral anticoagulants in the prevention of deep venous thrombosis. The control group had oral anticoagulants only from the evening before the day of operation, aimed at the 15 per cent thrombotest level. The dextran group had peroperative and postoperative dextran infusions as well. Radionuclide venography was used for thrombosis detection. The dextran group had a lower incidence of thrombosis, but more haemorrhagic problems. The incidence of thrombosis was high in both groups.

Experimental arthrosis. Early changes in synovial morphology and lysosomal enzyme activities.

The Hulth procedure was used to induce osteoarthrosis in a knee-joint in 36 rabbits, whereupon changes in chondral and synovial morphology and lysosomal enzyme activities were studied over a period of 3 months. A significant increase in enzyme activities was observed, which was more pronounced and seemed to occur earlier in the synovial membrane than in the cartilage. The synovial morphological changes were conspicuous in an early stage of the disease process and also seemed to precede the changes in chondral morphology. The results of this study suggest an important role of the synovial membrane in the pathogenesis of osteoarthrosis.