Fujio Higuchi

Hypersensitivity to Suture Anchors

Hypersensitivity to suture anchor is extremely rare. Herein, we present a case in which hypersensitivity to suture anchor was strongly suspected. The right rotator cuff of a 50-year-old woman was repaired with a metal suture anchor. Three weeks after the surgery, she developed erythema around her face, trunk, and hands, accompanied by itching. Infection was unlikely because no abnormalities were detected by blood testing or by medical examination. Suspicious of a metallic allergy, a dermatologist performed a patch testing 6 months after the first surgery. The patient had negative reactions to tests for titanium, aluminum, and vanadium, which were the principal components of the suture anchor. The anchor was removed 7 months after the first surgery, and the erythema disappeared immediately. When allergic symptoms occur and persist after the use of a metal anchor, removal should be considered as a treatment option even if the patch test result is negative.

Epiphyseal Fracture of the Coracoid Process Occurring at the Conjoined Tendon Origin

Fracture of the coracoid process is uncommon, and most previous studies have reported this fracture occurring in association with direct trauma to the shoulder or transmission of force from the upper arm or elbow (Ada and Miller 1991, Benton and Nelson 1971, Eyres et al. 1995). We present a case in which epiphyseal fracture occurred at the origin of the conjoined tendon following excessive muscle contraction. We believe this represents the first description of such a method of injury.

Biomechanical effect and clinical application of the hip joint moment reduction brace

A new brace, the hip joint moment reduction brace, has been designed and constructed. The basic construct of the brace incorporates only the thigh, and it minimally restricts ones activities of daily living. The concept of the brace is to reduce the frontal plane moment of the applied force against which the abductor muscle must contract to balance, and this reduction of the frontal plane moment results in reduction of the abductor muscle force. The brace uses the mechanism of the ischial weightbearing and lessens the abductor moment by transmitting load from the ischium through the condyle of the femur. In gait testing, the maximum ischial load taken up by the brace was 36.9% of the ground reaction force in the late stance phase, and the integrated electromyogram of the abductor muscle was reduced by 32.6% during the whole stance phase using this brace. These findings confirmed a reduction in the frontal plane moment of the hip joint and the potential for reduction in the load on the hip joint. The hip joint moment reduction brace is recommended as effective conservative management of hip disorders, such as coxarthrosis, that are caused or worsened by biomechanical insufficiency.

Calcific Tendonitis of the Rotator Cuff: An Unusual Case

Few case reports have described the surgical treatment of calcifying tendonitis of the subscapularis tendon. We present a case of symptomatic diffuse calcifying tendonitis involving the subscapularis and infraspinatus insertions that was difficult to detect arthroscopically. The patient was treated with arthroscopic incision of the tendinous insertions thorough removal of the calcific deposits and subsequent repair using a suture-anchor technique. Two years after the surgical procedure, the patient was completely pain-free and attained full range of motion. Radiographic evaluation performed 2 years after the procedure revealed no calcific deposits. We conclude that the combination of incision of the subscapularis and infraspinatus insertions, complete removal of the calcific deposits, and subsequent suture-anchor repair in an all-arthroscopic manner can lead to an excellent clinical outcome without compromising the functional integrity of the rotator cuff tendons.

Computer Simulation of Hip Osteotomies for Dysplastic Coxarthroses: Use of a Rigid Body Spring Model

We have used the rigid body spring model (RBSM) or discrete element analysis to investigate the biomechanical effect of hip osteotomies. A two-dimensional (2-D) two-element model was generated by anteroposterior (A-P) radiography. The pelvic and femoral elements were assumed to be rigid and interface springs were placed 1 mm apart along the articular contact area to simulate articular cartilage. Four subjects, who had a normal hip joint, early, advanced, and late stage of coxarthroses, respectively, were analyzed. The coxarthrotic subjects were analyzed preoperatively and at final follow-up. The resultant and modified resultant force of the femoral head, dislocation force, mean and maximum compressive stress on the joint, and X—Y and rotational deviations of the pelvic element were calculated. In the normal hip joint, the stress pattern on the joint surface was similar to the “sourcil” (“eyebrow”), as described by Pauwels [1]. In preoperative coxarthrosis, extreme stress was seen on the joint, especially where the joint space was narrowed. A dislocation force not observed in a normal hip joint was apparent, with the X—Y and rotational deviations being larger than in the normal hip joint. This tendency increased with progressing stages of coxarthrosis. In the final follow-up examination, all the simulated results were in contrast to those obtained preoperatively. A 3-D reconstruction computerized tomographic (CT) scan was used to visualize the hip joint and its operation, but this procedure is not clinically practical for every patient. Surgeons usually use only plane radiograms when planning hip operations, such as osteotomy or total hip arthroplasty. The RBSM is therefore clinically useful because of its simplicity, and 2-D RBSM can easily be utilized by using A-P radiograms for each patient. With this method the patient’s past radiographic data can also be utilized. A comparative study of clinical symptoms and simulated results using 2-D RBSM suggested that the simulated results were well correlated to the clinical symptoms. RBSM is clinically useful not only for evaluating each patient biomechanically but also for planning hip osteotomy.