ABSTRACT
The possibility of migration of cementless cups in total joints after prophylaxis of heterotopic ossification with irradiation or nonsteroidal antiinflammatory drugs is a concern. Data investigating component stability with digital methods are lacking. This prospective study analyzed the migration of cementless cups after indomethacin and irradiation prophylaxis with the digital Einzel-Bild-Röntgen-Analyse tool. The irradiation group (106 hips) and the indomethacin group (98 hips) were compared with 82 hips that did not receive any prophylaxis. The same cementless acetabular implants were used in all cases, and patients were observed clinically and radiographically at 2 and 5 years. At the 5-year followup, the number of cups that showed migration greater than 1 mm in the irradiation group (five), the indomethacin group (three), and the control group (four) were not different. No cup was considered loose on the radiographs and no patient underwent revision surgery. The results of our study indicate irradiation or short-course use of indomethacin for prophylaxis of heterotopic ossification did not negatively affect the stability of cementless cups in primary total hip arthroplasties.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Foreign-Body Migration/epidemiology , Indomethacin/therapeutic use , Ossification, Heterotopic/prevention & control , Acetabulum , Aged , Female , Hip Joint/radiation effects , Humans , Male , Middle Aged , Osteoarthritis, Hip/surgery , Prospective StudiesABSTRACT
BACKGROUND: Acetabular screw cups seem to give high primary stability. We analyzed the migration and loosening behavior of a first-generation screw cup in a longterm follow-up. PATIENTS AND METHODS: We examined 92 uncemented titanium alloy conical screw cups prospectively. Implant migration was assessed with a digital high-precision method (EBRA) with an accuracy of 1.0 mm. RESULTS: After mean 11 (0.5-18) years, 87 patients were available for examination and 5 patients had died. 32 implants had been revised and 7 cases showed radiographic evidence of loosening. The 10-year survival rate was 71%. Migration of more than 1 mm occurred in 53 hips. Implant survival was strongly associated with an annual migration of greater than 0.2 mm. INTERPRETATION: The long-term behavior of this cup is not satisfactory. In spite of extraordinarily high primary implant stability, secondary osseointegration of this cup often fails. The annual migration rate represents a valid parameter for prediction of implant survival.
Subject(s)
Arthroplasty, Replacement, Hip/adverse effects , Bone Screws , Hip Prosthesis/adverse effects , Acetabulum/surgery , Adult , Arthroplasty, Replacement, Hip/instrumentation , Bone Screws/adverse effects , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Prosthesis Design , Prosthesis Failure , TitaniumABSTRACT
PURPOSE: To confirm the neuromuscular integrity of the rotator cuff and to investigate the effect of different contraction patterns on shoulder function, we sonographically analyzed dynamic contraction patterns of this muscle group. METHODS: Fifty supra- and 50 infraspinatus muscle contraction patterns of patients with different shoulder pathologies examined with a 7.5-MHz transducer were recorded and saved as video files. Both data sets were analyzed by 3 independent observers who then assigned a grade to each contraction pattern: normal, slightly disturbed, severely disturbed, or no contraction. Intra- and inter-observer variations were calculated. In 43 patients with isolated supraspinatus tears, the clinical relation to shoulder function as measured with the Constant score was evaluated. RESULTS: In the 100 cases tested, the intraclass correlations for the 3 observers were 0.82, 0.88, and 0.88. The inter-observer reliability was 0.74. No pair of first and second readings for either the supraspinatus or infraspinatus muscle differed by more than 1 grade. In patients with a supraspinatus tear, the contraction type of the supraspinatus correlated significantly with the Constant score (p=0.02). CONCLUSIONS: When dynamic ultrasonography is used to assess the contraction patterns of the supra- and infraspinatus muscles, good intra- and inter-observer reliability is attained. Because a better contraction type correlates significantly with better shoulder function, this new diagnostic criterion may improve decision-making in the treatment of shoulder diseases.
Subject(s)
Muscle Contraction , Rotator Cuff/diagnostic imaging , Humans , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/physiopathology , Observer Variation , Rotator Cuff/physiopathology , Rotator Cuff Injuries , Shoulder Joint/diagnostic imaging , Shoulder Joint/physiopathology , UltrasonographyABSTRACT
Varying results and a high rate of subsidence have been reported for the straight femoral stem (M.E. Muller) made of titanium alloy. We examined subsidence in 135 titanium-alloy straight stems implanted with high viscosity cement after 68.8+/-11.5 months using a digital high-precision method (EBRA-FCA). One revised implant showed a subsidence of 14.6 mm and another 2.5 mm over 5 years. A third implant without migration was found to be loose. The 122 implants without loosening showed a mean subsidence of 0.1+/-0.1 mm, and focal osteolysis was seen in two. Altogether, we found subsidence of the titanium stems very small. The small subsidence may be related to the use of high viscosity bone cement.
