Kaj Klaue

A New Periacetabular Osteotomy for the Treatment of Hip Dysplasias Technique and Preliminary Results

A new periacetabular osteotomy of the pelvis has been used for the treatment of residual hip dysplasias in adolescents and adults. The identification of the joint capsule is performed through a Smith-Petersen approach, which also permits all osteotomies to be performed about the acetabulum. This osteotomy does not change the diameter of the true pelvis, but allows an extensive acetabular reorientation including medial and lateral displacement. Preparations and injections of the vessels of the hip joint on cadavers have shown that the osteotomized fragment perfusion after correction is sufficient. Because the posterior pillar stays mechanically intact the acetabular fragment can be stabilized sufficiently using two screws. This stability allows patients to partially bear weight after osteotomy without immobilization. Since 1984, 75 periacetabular osteotomies of the hip have been performed. The corrections are 31 degrees for the vertical center-edge (VCE) angle of Wiberg and 26 degrees for the corresponding angle of Lequesne and de Seze in the sagittal plane. Complications have included two intraarticular osteotomies, a femoral nerve palsy that resolved, one nonunion, and ectopic bone formation in four patients prior to the prophylactic use of indomethacin. Thirteen patients required screw removal. There was no evidence of vascular impairment of the osteotomized fragment.

Clinical, Quantitative Assessment of First Tarsometatarsal Mobility in the Sagittal Plane and Its Relation to Hallux Valgus Deformity

Today, bunion surgery is still controversial. Considering that a bunion deformity in fact may be a result of multiple causes, the rationale of the currently applied techniques of surgical treatment has not been conclusively demonstrated. In view of the known hypermobility syndrome of the first ray that results in insufficient weightbearing beneath the first metatarsal head, the relationship between this syndrome and hallux valgus deformity has been investigated. The results suggest a direct relationship between painful hallux valgus deformity and hypermobility in extension of the first tarsometatarsal joint. A pathological mechanism of symptomatic hallux valgus is proposed that relates this pathology with primary weightbearing disturbances in the forefoot where angulation of the first metatarsophalangeal joint is one of the consequences. The alignment of the metatarsal heads within the sagittal plane seems to be a main concern in many hallux valgus deformities. As a consequence, treatment includes reestablishing stable sagittal alignment in addition to the horizontal reposition of the metatarsal over the sesamoid complex. As an example, first tarsometatarsal reorientation arthrodesis regulates the elasticity of the multiarticular first ray within the sagittal plane and may be the treatment of choice in many hallux valgus deformities.

CT evaluation of coverage and congruency of the hip prior to osteotomy

A computer-assisted model has been developed to improve the results of surgical techniques for reconstruction of hip dysplasia. This method assesses the coverage and congruency of the femoral head by evaluating multiple factors that may influence surgical planning. It achieves a more reliable image because the measurements are based on a three-dimensional representation, and attention is focused on the cartilaginous coverage of the femoral head. A method to simulate the operative correction helps the surgeon in planning osteotomies of the femur and pelvis. This technique clearly establishes both deficiencies of coverage and congruency of pathologic hips and thus may be used to create a more precise definition and treatment of multiple congenital abnormalities.

Bone regeneration in long-bone defects: tissue compartmentalisation? In vivo study on bone defects in sheep

Regeneration of living tissue varies with species, age and type of tissue, and undoubtedly with the biological and mechanical environment of the precise tissue. Autologous cancellous bone grafting is a well-known technique that provides bony regeneration. We investigated the efficiency of autologous bone grafting in a well-vascularised muscle environment, and additionally when isolated from the muscle and connected only to the bony environment. We designed a reproducible animal model producing a stable 3cm middiaphyseal bone and periosteal defect on sheep femurs and created a foreign-body membrane with a temporary poly-methylmethacrylate spacer. The foreign-body membrane had the outer dimension of the removed bone segment. We then ascertained the bony regeneration potential within the bone defect using autologous cancellous bone graft. Regeneration of bone is enhanced considerably by an autologous foreign-body membrane that separates the interfragmentary space from the muscular environment. This effect is independent of the autologous bone graft. The results suggest that bone behaves like a compartment that protects its specific humoral or its cellular environment, or both. Regeneration of bone can be enhanced by compartmentalisation of the bone defect.

The Classic: A New Periacetabular Osteotomy for the Treatment of Hip Dysplasias: Technique and Preliminary Results

A new periacetabular osteotomy of the pelvis has been used for the treatment of residual hip dysplasias in adolescents and adults. The identification of the joint capsule is performed through a Smith-Petersen approach, which also permits all osteotomies to be performed about the acetabulum. This osteotomy does not change the diameter of the true pelvis, but allows an extensive acetabular reorientation including medial and lateral displacement. Preparations and injections of the vessels of the hip joint on cadavers have shown that the osteotomized fragment perfusion after correction is sufficient. Because the posterior pillar stays mechanically intact the acetabular fragment can be stabilized sufficiently using two screws. This stability allows patients to partially bear weight after osteotomy without immobilization. Since 1984, 75 periacetabular osteotomies of the hip have been performed. The corrections are 31° for the vertical center-edge (VCE) angle of Wiberg and 26° for the corresponding angle of Lequesne and de Seze in the sagittal plane. Complications have included two intraarticular osteotomies, a femoral nerve palsy that resolved, one nonunion, and ectopic bone formation in four patients prior to the prophylactic use of indomethacin. Thirteen patients required screw removal. There was no evidence of vascular impairment of the osteotomized fragment.

Extra-articular augmentation for residual hip dysplasia. Radiological assessment after Chiari osteotomies and shelf procedures

The Chiari osteotomy and various shelf procedures are used to augment the weight-bearing area in dysplastic acetabula. The new articular surface derives by metaplasia from the acetabular rim and joint capsule, and is therefore of poorer quality than congruous hyaline cartilage. We reviewed 32 patients after augmentation procedures, using conventional radiographs and three-dimensional reconstruction from CT scans. We showed that Chiari osteotomy and shelf procedures generally achieve less than complete cover, especially over the posterolateral quadrant of the femoral head. Our results suggest that alternative methods which reorientate the whole of the acetabulum are the treatment of choice. Augmentation procedures remain as a salvage option when reorientation is inappropriate or the original hyaline cartilage surface is absent, as in subluxed joints with a secondary acetabulum. Computerised assessment is recommended before operation to assess existing cover and the possible extent of provision of new cover.

Development and testing of a new self-locking intramedullary nail system: testing of handling aspects and mechanical properties

A distal interlocking system has been developed which is easy to use, carries out an aligning effect on the distal fracture fragment, reduces the exposure to radiation for the surgeon and the patient, and allows for a decrease in operating time. The goal of this study was to develop and test the handling and mechanical properties of two prototype nails in comparison to a conventional interlocking nail concept (Unreamed Femoral Nail system). It was shown that the prototype designs represent an improvement over this system. Both designs were easy to use. The prototype with the asymmetrically offset interlocking bolts exhibited an exemplary aligning effect on the distal fracture fragment. Both designs showed mechanical stability comparable or superior to that of the standard contralateral control in four-point-bending and axial compression. Given the handling advantages afforded by the new self-locking intramedullary implant system, it would be expected that use of this system would reduce exposure to radiation for the surgeon as well as the patient and allow for a decrease in operating time. This new development may be of particular interest for clinics without access to fluoroscopes in the operating theatre (e.g. in the Third World).

Compartment syndrome of the foot

Compartment syndrome of the foot has been described recently as a serious complication after crush trauma and severe fractures. It represents a surgical emergency and corresponds to stage I of Volkmanns contracture. Untreated, it will lead to pain and static changes of the foot with fixed claw toes and a contracted forefoot in more than 50% of the cases. Percutaneous measuring of intrinsic compartment pressure allows rapid assessment of pathological values (more than 30 mmHg). Fasciotomies of the 9 compartments of the foot are preferentially performed through one medial and two dorsal approaches. During the last two years we have measured pathological compartment pressures in 8 traumatized patients in whom an acute compartment syndrome of the foot was clinically suspected. Pressure values of more than 100 mmHg were demonstrated. In all patients foot compartments were released immediately. Except for one patient, with a persisting hyposensibility, all patients showed a complete recovery of the initial neuromuscular symptoms.

Hindfoot Issues in the Treatment of the Cavovarus Foot

Cavovarus foot deformity is a result of a dysbalance of the extrinsic musculature about the foot. Because of the multi-articular bony structure of the foot and ankle, the slightest imbalance of muscular forces causes osteo-articular malalignment and consequent gross deformities. This article discusses hindfoot issues involved in the treatment of cavovarus foot.

Morphological 3-dimensional assessment, pre-operative simulation and rationale of intra-operative navigation in orthopaedic surgery: Practical application for re-orienting osteotomies of the hip joint

Abstract A few events represent progress in the development of orthopaedic surgery. Imagery, and especially imagery by Roentgen rays, brought up modern orthopaedic surgery about one hundred years ago. So-called conventional radiography also brought with it disadvantages and pitfalls and misinterpretations mostly due to the ‘shadow’ technique of imaging by planar projection of three-dimensional structures. Surgical handling of the locomotor system is basically subject to the physical rules of statics and dynamics. Such handling may (and should today) be preceded by preoperative evaluation and planning using technology which operates within three-dimensional space. Such technologies have been developed recently in the form of computerized radiographic tomography (CT) and computerized nuclear magnetic imaging (MRI). The path to the practical application of these techniques in orthopaedic surgery requires specialized software, the use of which is described here. Such software introduces virtual reality in the interpretation of pathology and simulation of corrective means by osteotomy. Surgical handling in orthopaedic surgery, similar to aircraft navigation, thus gains in reliability and precision and loses some of its adventurous aspect. Using virtual reality in simulating re-orientating osteotomies can also lead to misinterpretation, for example, due to underestimating the role of the soft tissues. Soft tissues can be represented in static views but must be excluded when using intra-operative navigation. The rationale of using three-dimensional imagery has clear limits which have to be respected. Direct visualization of the hard tissue (bone) is mandatory in correction osteotomies even when using interactive image control because of the unknown behaviour of soft tissue under strain. Endoscopic techniques are useful tools, complementing 3-D imaging and image interaction.