Biomedical subjects
G J van der Werf
Publications and source records attributed to G J van der Werf.
Operative correction of posttraumatic and congenital swanneck deformity--a new technique.
Volar plate reconstruction by using a part of the slip of the superficialis tendon is a new technique in the treatment of posttraumatic and congenital swanneck deformity. This small series represents two patients with a posttraumatic swanneck deformity due to volar plate rupture and one patient with a congenital swanneck deformity in six fingers. The results of the operation with a two years follow-up show seven fingers with a normal flexion-extension range without hyperextension. Only one finger has an extension lag of five degrees. All fingers have a normal grip strength and normal fine movements without pain. There were no complications.
Radiotherapy in the prevention of recurrence of paraarticular ossification in total hip prostheses.
Ectopic bone formation or paraarticular ossification after total hip arthroplasty can be a very disabling factor. In patients with this problem, range of motion and walking ability may be reduced and pain can occur. In severe cases it seems logical to remove this paraarticular ossified tissue, but without measures to prevent its recurrence this will be of no real value. This study shows the effectiveness of irradiation soon after excision of the ectopic bone mass, with a total dosage of 20 Gy (2000 rad) given in ten fractions, in preventing, or at least inhibiting, the recurrence of paraarticular ossification in 16 patients. A dramatic improvement in hip function, walking ability, and relief of pain is demonstrated.
Direct repair of lumbar spondylolysis.
Direct repair of the defect in spondylolysis has been performed on 12 patients with a mean age of 29 years. With an average follow-up period of 3 years, 8 patients had a good result, 2 patients improved only slightly and 2 patients remained unchanged.
Transposition of the posterior tibial tendon in spastic equinovarus.
Eleven posterior tibial tendon transfers were performed in eight patients with spastic equinovarus with an average follow-up of 3 years (range 1 1/2-6 1/2 years). The main goals--to eliminate the need for braces and to improve gait--were achieved in all patients. An adequate operation technique kept the well-known postoperative complications, e.g., valgus and calcaneal deformity, to a minimum.
Tarsometatarsal fracture-dislocation.
Closed and open treatment were compared in 12 cases of tarsometatarsal dislocation. When the dislocation involved the lateral component only, good results were observed in one of three cases treated closed and six of seven cases treated open. It is essential to reduce and stabilize the dislocation which is often overlooked unless carefully analyzed clinically and radiographically.