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Reinhold Ganz

Publications and source records attributed to Reinhold Ganz.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of six radiographic projections to assess femoral head/neck asphericity.

UNLABELLED: Early radiographic detection of femoroacetabular impingement might prevent initiation and progression of osteoarthritis. The structural abnormality in femoral-induced femoroacetabular impingement (cam type) is frequently asphericity at the anterosuperior head/neck contour. To determine which of six radiographic projections (anteroposterior, Dunn, Dunn/45 degrees flexion, cross-table/15 degrees internal rotation, cross-table/neutral rotation, and cross-table/15 degrees external rotation) best identifies femoral head/neck asphericity, we studied 21 desiccated femurs; 11 with an aspherical femoral head/neck contour and 10 with a spherical femoral head/neck contour. To radiographically quantify femoral head asphericity, we measured the angle where the femoral head/neck leaves sphericity (angle alpha). The aspherical femoral head/neck contours had a greater maximum angle alpha (70 degrees ) compared with the spherical head/neck contours (50 degrees ). The angle alpha varied depending on the radiographic projection: it was greatest in the Dunn view with 45 degrees hip flexion (71 degrees +/- 10 degrees ) and least in the cross-table view in 15 degrees external rotation (51 degrees +/- 7 degrees ). Diagnosis of a pathologic femoral head/neck contour depends on the radiologic projection. The Dunn view in 45 degrees or 90 degrees flexion or a cross-table projection in internal rotation best show femoral head/neck asphericity, whereas anteroposterior or externally rotated cross-table views are likely to miss asphericity. LEVEL OF EVIDENCE: Prognostic study, level II-1 (retrospective study).

Female↗
PubMed2006

Modified complete synovectomy prevents recurrence in synovial chondromatosis of the hip.

Synovial chondromatosis of the hip is a rare disorder with few published reports regarding treatment and outcomes, and therefore, selecting the optimal surgical treatment is difficult. We reviewed eight patients with monoarticular synovial chondromatosis of the hip who had joint débridement and a modified total synovectomy performed through a surgical hip dislocation with a trochanteric flip osteotomy. Patients were evaluated for recurrence of disease, progression of osteoarthritis, clinical outcomes, and subsequent reoperations. The minimum followup was 4 years (mean, 6.5 years). At final review, no patient had recurrence of disease. Two patients had progression of osteoarthritis requiring total hip arthroplasties at 5 and 10 years after the initial surgical intervention. These patients did not show recurrent disease on histologic examination of the synovial membrane at the time of the arthroplasty. The six patients with preserved joints were followed up for a mean of 6.2 years. The mean Merle d'Aubigné and Postel score in this group was 16.5 points (range, 15-18 points) at the latest followup. There were no major or minor complications related to this treatment. Our midterm results suggest that open débridement with modified total synovectomy is an effective treatment that prevents recurrence of disease and provides substantial pain relief. Surgical hip dislocation allows safe and complete access to the joint for débridement and synovectomy with no added morbidity.

Adult↗
PubMed2006

Treatment of femoro-acetabular impingement: preliminary results of labral refixation.

BACKGROUND: Recent advances in the understanding of the anatomy and function of the acetabular labrum suggest that it is important for normal joint function. We found no available data regarding whether labral refixation after treatment of femoro-acetabular impingement affects the clinical and radiographic results. METHODS: We retrospectively reviewed the clinical and radiographic results of fifty-two patients (sixty hips) with femoro-acetabular impingement who underwent arthrotomy and surgical dislocation of the hip to allow trimming of the acetabular rim and femoral osteochondroplasty. In the first twenty-five hips, the torn labrum was resected (Group 1); in the next thirty-five hips, the intact portion of the labrum was reattached to the acetabular rim (Group 2). At one and two years postoperatively, the Merle d'Aubigné clinical score and the Tönnis arthrosis classification system were used to compare the two groups. RESULTS: At one year postoperatively, both groups showed a significant improvement in their clinical scores (mainly pain reduction) compared with their preoperative values (p = 0.0003 for Group 1 and p < 0.0001 for Group 2). At two years postoperatively, 28% of the hips in Group 1 (labral resection) had an excellent result, 48% had a good result, 20% had a moderate result, and 4% had a poor result. In contrast, in Group 2 (labral reattachment), 80% of the hips had an excellent result, 14% had a good result, and 6% had a moderate result. Comparison of the clinical scores between the two groups revealed significantly better outcomes for Group 2 at one year (p = 0.0001) and at two years (p = 0.01). Radiographic signs of osteoarthritis were significantly more prevalent in Group 1 than in Group 2 at one year (p = 0.02) and at two years (p = 0.009). CONCLUSIONS: Patients treated with labral refixation recovered earlier and had superior clinical and radiographic results when compared with patients who had undergone resection of a torn labrum. Although the results must be considered preliminary, we now recommend refixation of the intact portion of the labrum after trimming of the acetabular rim during surgical treatment of femoro-acetabular impingement.

Acetabulum↗
PubMed2006

Hip joint-preserving surgery: beyond the classic osteotomy.

It has been postulated that hip osteoarthritis is often caused by developmental anatomic deformities. Recent studies have demonstrated that relatively subtle anatomic abnormalities such as acetabular retroversion, acetabular overcoverage, and decreased offset of the femoral head-neck junction also may lead to pain and osteoarthritis. Advances in surgical techniques such as the periacetabular osteotomy, safe surgical dislocation of the hip, and hip arthroscopy have provided the surgeon with effective and safe tools to correct these anatomic problems. Clinical and radiographic techniques are used to identify these anatomic abnormalities.

Acetabulum↗
PubMed2006

Nonarthroplasty surgical treatment of hip osteoarthritis.

The two conditions that give rise to osteoarthritis of the hip are dysplasia and nondysplasia. Dysplasia, commonly associated with anterolateral acetabular deficiency, may lead to osteoarthritis in 40% of patients in the United States with this condition. In a distinct category of patients with so-called idiopathic arthritis, there is no apparently identifiable cause for osteoarthritis. There is emerging evidence that subtle morphologic abnormalities around the hip, resulting in femoroacetabular impingement, may often be a contributing factor to osteoarthritis in young patients.

Humans↗
PubMed2005

Wear particles and surface topographies are modulators of osteoclastogenesis in vitro.

Prosthetic and osteosynthetic implants from metal alloys will be indispensable in orthopedic surgery, as long as tissue engineering and biodegradable bone substitutes do not lead to products that will be applied in clinical routine for the repair of bone, cartilage, and joint defects. Therefore, the elucidation of the interactions between the periprosthetic tissues and the implant remains of clinical relevance and several factors are known to affect the longevity of implants. Within this study, the effects of metal particles and surface topography on the recruitment of osteoclasts was investigated in vitro in a coculture of osteoblasts and bone marrow cells. The cells were grown in the presence of particles of different sizes and chemical composition or on metal discs with polished or sandblasted surfaces, respectively. At the end of the culture, newly formed osteoclasts were counted. Osteoclastogenesis was reduced when particles were added directly to the coculture. The effect depended on the size of the particles, small particles exerting stronger effects than larger ones. The chemical composition of the particles, however, did not affect the development of osteoclasts. In cocultures grown on sandblasted surfaces, osteoclasts developed at higher rates than they did in cultures on polished surfaces. The data demonstrate that wear particles and implant surfaces affect osteoclastogenesis and thus may be involved in the induction of local bone resorption and the formation of osteolytic lesions, leading eventually to the loosening of orthopedic implants.

Animals↗
PubMed2005

Acetabular reconstruction using a roof reinforcement ring with hook for total hip arthroplasty in developmental dysplasia of the hip-osteoarthritis minimum 10-year follow-up results.

The outcome of 33 total hip arthroplasties using an acetabular reinforcement ring with hook for osteoarthritis associated with developmental dysplasia of the hip was reevaluated after a minimal follow-up of 10 years (average, 10.8 years). Most cases comprised Crowe type II (22 hips) and type III (7 hips) dysplasia. The mean D'Aubigné score increased from 7 to 15 points. Three revisions (9%) were performed for aseptic loosening, 2 of them had a structural autograft. None of the unrevised 30 acetabular reconstructions showed definite radiographic signs of loosening. These results compare favorably with the literature and the acetabular reinforcement ring with hook presents a versatile tool for acetabular bone stock deficiencies.

Acetabulum↗
PubMed2005

Anatomic considerations for the choice of surgical approach for hip resurfacing arthroplasty.

A number of surgical exposures have been advocated over the past 20 years by the pioneers of resurfacing hip arthroplasty and include the anterior, anterolateral, lateral, and posterolateral approaches. Not all of these approaches, however, appear to provide adequate exposure while respecting the local biology that seems to be imperative for the procedure. Based on an anatomic study, the most "bio-logical" surgical approach for hip resurfacing arthroplasty appears to be through a lateral or posterolateral approach using a digastric trochanteric osteotomy combined with an anterior hip dislocation. These exposures avoid injury to the medial femoral circumflex artery supplying the femoral head and allow access and treatment to the commonly observed hip pathologies that are frequently located anteriorly.

Adult↗
PubMed2005

Distribution of vascular foramina around the femoral head and neck junction: relevance for conservative intracapsular procedures of the hip.

Precise knowledge of femoral head vascular anatomy is mandatory for the safe execution of intracapsular surgical procedures aimed at preserving the hip joint. No quantitative topographic data exist concerning the exact location and distribution of the entrance of these vessels through nutrient vascular foramina at the femoral head and neck junction. This study shows that only a few significant retinacular vessels may reach the adult femoral head on its anterior aspect and that most vascular foramina are located close to the antero- and posterosuperior regions of the femoral head and neck junction. This larger segment should be carefully protected during any conservative intracapsular procedure of the hip and may be desirable in femoral head resurfacing arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed2005

Fibrocystic changes at anterosuperior femoral neck: prevalence in hips with femoroacetabular impingement.

PURPOSE: To retrospectively evaluate if there is an association between juxta-articular fibrocystic changes at the anterosuperior femoral neck and femoroacetabular impingement (FAI). MATERIALS AND METHODS: The institutional review board approved this study and did not require informed patient consent. An orthopedic surgeon and a radiologist in consensus retrospectively reviewed the anteroposterior (AP) pelvic radiographs of 117 hips with FAI and compared these images with the AP radiographs of a control group of 132 hips with developmental dysplasia (DD) to determine the prevalence of juxta-articular fibrocystic changes at the anterosuperior femoral neck. Criteria for juxta-articular fibrocystic changes at the anterosuperior femoral neck were location close to the physis and a diameter (of the fibrocystic change) of greater than 3 mm. The sensitivity and specificity of AP pelvic radiography in the detection of these fibrocystic changes were calculated by using an additional 61 hips with FAI and on the basis of findings at magnetic resonance (MR) arthrography, which was routinely performed for assessment of FAI. In 24 patients who underwent joint-preserving surgery for FAI, the fibrocystic changes were localized intraoperatively and the spatial relation of the region of these changes to the area of FAI was identified. Joint-preserving surgery consisted of anterior surgical dislocation of the hip with osteochondroplasty of the proximal femur and/or the acetabular rim to improve the impingement-free range of hip motion. For statistical comparisons, nonparametric tests were performed. RESULTS: Fibrocystic changes were identified on the AP radiographs of 39 (33%) of the 117 FAI-affected hips and on none of the radiographs of the 132 DD-affected hips. According to MR arthrogram findings, the sensitivity, specificity, and positive and negative predictive values of AP pelvic radiography were 64%, 93%, 91%, and 71%, respectively. The mean diameter of the juxta-articular fibrocystic changes was 5 mm (range, 3-15 mm); smaller lesions were more prevalent. Dynamic MR imaging with the hip flexed and intraoperative observations revealed a close spatial relationship between the region of the fibrocystic changes at the anterosuperior femoral neck and the acetabular rim. CONCLUSION: The high prevalence of juxta-articular fibrocystic changes at the anterosuperior femoral neck and their spatial relation to the impingement site suggest an association and possible causal relationship between these alterations and FAI.

Acetabulum↗
PubMed2004

Advancement of the vastus lateralis muscle for the treatment of hip abductor discontinuity.

Impaired abductor function of the hip resulting from a discontinuous gluteus medius often is encountered in revision hip surgery. If the gluteus medius can be reattached to the proximal femur, functional results are satisfactory. If this is not possible, it would be desirable to restore the continuity of the gluteus medius by bridging the defect with local tissue. An anatomic study was performed in 15 cadavers, and proximal advancement of the vastus lateralis without injury to the neurovascular pedicle was 8 cm (range, 7-10 cm). Clinically, the technique was used in 3 patients. At follow-up, both living patients walked without a cane and both were able to hold the leg abducted against moderate pressure. Proximal advancement of the vastus lateralis can successfully bridge defects of the gluteus medius and partially restores abductor function.

Adult↗
PubMed2004

Potential role of pre-existing blood vessels for vascularization and mineralization of osteochondral grafts: an intravital microscopic study in mice.

BACKGROUND: The aim of this study was to develop an experimental model that allows to elude the potential role of the preexisting graft microvasculature for vascularization and mineralization of osteochondral grafts. ANIMALS AND METHODS: For that purpose, the II-IV metatarsals of fetal DDY-mice known to be nonvascularized at day 16 of gestation (M16) but vascularized at day 18 (M18) were freshly transplanted into dorsal skin fold chambers of adult DDY mice. Using intravital microscopy angiogenesis, leukocyte-endothelium interaction and mineralization were assessed for 12 days. RESULTS: Angiogenesis occurred at 32 hours in M18, but not before 57 hours in M16 (p = 0.002), with perfusion of these vessels at 42 hours (p = 0.005) and 65 hours (p = 0.1), respectively. Vessels reached a density three times as high as that of the recipient site at day 6, remaining constant until day 12 in M18, whereas in M16 vascular density increased from day 6 and reached that of M18 at day 12 (p = 0.04). Leukocyte-endothelium interaction showed sticker counts elevated by a factor of 4-5 in M18 as compared to M16. Mineralization of osteochondral grafts did not differ between M16 and M18, which significantly increased in both groups throughout the observation period. INTERPRETATION: We propose the faster kinetics in the angiogenic response to M18 and the elevated counts of sticking leukocytes to rest on the potential of establishing end-to-end anastomoses (inosculation) of the vascularized graft with recipient vessels.

Animals↗
PubMed2004

Magnetic resonance arthrography of labral disorders in hips with dysplasia and impingement.

Despite the fact that classic studies on osteoarthritis of the hip have shown the periphery of the hip to be prone to degeneration, it was not until recently that an abnormal acetabular labrum has been associated with osteoarthritis. This study was designed to determine whether magnetic resonance arthrography can show differences in disorders of the labrum (tears, size, ganglion formation) expected in symptomatic patients with developmental dysplasia of the hip and anterior femoroacetabular impingement. Fourteen patients in each group were evaluated preoperatively not only clinically but also with conventional radiographs and magnetic resonance arthrographs. In both conditions, disorders of the labrum localized identically with a predilection to the anterosuperior quadrant of the acetabulum. Labral tears were observed in nine hips of each group. The labrum was enlarged in 12 hips with dysplasia but in none of the hips with impingement. Ganglion formation in the periacetabular area was seen in 10 hips with dysplasia and three hips with impingement. These findings provide evidence that the anterosuperior acetabulum represents the initial fatiguing site of the hip under both conditions. Based on these data, the size of the labrum and the presence of soft tissue ganglia seem to be good predictors for the presence of developmental dysplasia, whereas the presence of tears did not differentiate between conditions. The capability of magnetic resonance arthrography to show these differences in labral disorders suggests this method is a helpful diagnostic tool that can aid in defining the most appropriate treatment strategy.

Adolescent↗
PubMed2004

Bilateral spontaneous periacetabular fracture: an unusual complication of multiple sclerosis.

We describe an unusual case of a 43-year-old woman who had developed bilateral spontaneous periacetabular fractures secondary to severe myoclonic contractions. The absence of antecedent history of trauma and detection of muscular spasticity at presentation prompted neurologic investigations that led to the diagnosis of multiple sclerosis in this patient. The fractures were treated successfully by open reduction and internal fixation initially. Since fracture reduction was delayed for almost 1 year, a special distraction frame had to be used. Deterioration in the medical condition of the patient with return of severe spasticity caused a dramatic failure of the fixation on one side 2 years later. This case report confirms that fractures, usually requiring high-impact trauma, can and do develop spontaneously in patients with sustained myoclonic contractions, and these fractures can be the presenting indication of an underlying neuromuscular disorder.

Acetabulum↗
PubMed2004

Femoroacetabular impingement as a factor in the development of nonunion of the femoral neck: a report of three cases.

OBJECTIVES: Description of an anatomic condition where a femoroacetabular impingement was identified as the cause for the development of nonunion of the femoral neck. DESIGN: Retrospective analysis. SETTING: University hospital. PATIENTS: Three patients, aged 27 to 74 years, in whom, after exclusion of other known factors, a femoroacetabular impingement was identified as the cause for the nonunion of a femoral neck fracture. INTERVENTION: Surgical correction of the femoroacetabular impingement. MAIN OUTCOME MEASUREMENT: Intraoperative verification of femoroacetabular impingement. Healing of the femoral neck non-union. RESULTS: In all 3 patients, femoroacetabular impingement was confirmed at surgery. After elimination of the cause for impingement, all nonunions went on to uneventful healing. CONCLUSIONS: A femoroacetabular impingement mechanism is proposed as a cause for nonunion of femoral neck fractures. Predisposing factors such as bulging at the fracture site or decreased femoral-neck offset should be addressed at the time of initial fracture treatment.

Adult↗
PubMed2004

Morphologic characteristics of acetabular dysplasia in proximal femoral focal deficiency.

A retrospective radiographic analysis of the acetabulum of 13 patients (14 hips) with proximal femoral focal deficiency (PFFD), clinically classified into Gillespie and Torode type 1, was performed to better understand its morphologic features at maturity. The version of the proximal part of the acetabulum was determined quantitatively and qualitatively. All 14 hips showed residual or borderline acetabular dysplasia with a mean lateral centre-edge angle of -1.5degrees and an acetabular index of 30degrees. The acetabular dome was retroverted in all hips and averaged -24degrees. Acetabular deficiency compared with the opposite side, while not present with respect to the anterior wall, averaged 12% with respect to the posterior wall. Dysplasia associated with type 1 PFFD is therefore fundamentally different from that seen in developmental residual hip dysplasia. Clinically, despite radiographic evidence of dysplasia, 57% were without clinical manifestations of hip pathology. This may be due to a number of factors including age of last radiograph, severity of dysplasia, and the decreased functional demand placed on the hip in some individuals with associated malformations. For the symptomatic hip, the posterior insufficiency and relative retroversion of the acetabular dome should be taken into consideration in planning reorientation procedures. This can help to prevent problems of persistent subluxation or acetabulo-femoral impingement following reconstruction.

Acetabulum↗
PubMed2004

Previous Bernese periacetabular osteotomy does not compromise the results of total hip arthroplasty.

It is not known if a previous periacetabular osteotomy poses technical difficulties and may increase the incidence of complications after total hip arthroplasty. The records of 41 patients who had THA after periacetabular osteotomy were evaluated. Followup averaged 6.9 years (range, 2-14 years). The average interval from osteotomy to total hip arthroplasty was 6.3 years (range, 4 months-14 years). Total hip arthroplasty provided significant relief of pain and improvement in function for all the patients. The acetabulum was judged to be retroverted in 23 patients and special attention to component positioning was needed. An abnormal proximal femoral anatomy secondary to previous intertrochanteric osteotomy or underlying dysplasia, or trochanteric overgrowth necessitated the use of trochanteric osteotomy for exposure in 24 patients. There were an acceptable number of complications and two revisions in the series. Aseptic loosening of the femoral component in one patient (one hip) and acetabular component in another patient (one hip) were the reasons for the two revisions. Total hip arthroplasty with technical consideration and careful evaluation of the acetabular version and relocated teardrop can be done safely in patients with a previous periacetabular osteotomy and should provide excellent results.

Acetabulum↗