Piotr Kozłowski

The role of the acetabulum in perthes disease

Abstract: The purpose of this study is to evaluate the changes in the shape of acetabulum from the onset of the disease to the skeletal maturity in Legg-Calvé-Perthes disease. The study population consisted of 243 patients with unilateral involvement who had reached skeletal maturity at last follow-up. All hips were treated by containment methods (which included bed rest and traction in abduction, Petri cast, brace, varus osteotomy, Salter osteotomy, and shelf acetabuloplasty). Necrosis of the femoral head was estimated according to the lateral pillar classification and late results according to the Stulberg classification. Changes in the shape of the acetabulum were divided into 3 groups: type I-normal, concave lateral acetabulum margin; type II-flat, horizontal lateral acetabulum margin; and type III-convex, sloping acetabular margin. Roentgenograms performed during the fragmentation stage revealed type I changes in 78 (32.1%) hips, type II in 136 (55.7%), and type III in 29 (12.2%). At the last follow-up, there were type I changes in 124 (51.2%) hips, type II in 81 (33.5%), and type III in 38 (15.3%). The statistical analysis revealed no significant statistical difference between the age at the onset and gender with regard to acetabular changes. There was significant statistical correlation between the lateral pillar classification, subluxation of the femoral head, the range of hip abduction, and the Stulberg classification with regard to acetabular changes. A type III was statistically associated with lateral pillar classification group C, major subluxation of the femoral head, limited hip abduction, and in Stulberg group 3, 4, or 5. Only surgical methods of treatment improved the acetabular shape at the last follow-up (P < 0.05). In our opinion, the lateral acetabulum shape plays a very important role during the remodeling of the deformed proximal femoral epiphysis.

Leg length discrepancy in Legg-Calve-Perthes disease.

The purpose of this study was to determine the incidence of the leg length discrepancy (LLD) in Legg-Calve-Perthes disease and whether there is any correlation between LLD and age at onset, gender, type of treatment, and severity of disease. The study population consisted of 261 patients with unilateral involvement who had reached skeletal maturity at last follow-up. All hips were treated by containment methods (bed rest and traction in abduction, Petri cast, brace, varus osteotomy, Salter osteotomy, and shelf acetabuloplasty). The late results were classified according to the Stulberg classification. LLD was found in 33 patients and ranged from 1 to 5.2 cm (average 2.51 cm). The limb shortening was observed in Herring group B (average 2.18 cm) and C (average 2.82 cm) and was statistically significant more common in group C. The statistical analysis revealed no statistical difference between the age at onset, sex, and type of treatment with regard to LLD; nevertheless, patients in Herring group C with LLD were younger than patients in group B, and LLD was seen more often after varus osteotomy. The amount of residual shortening of the affected limb in Legg-Calve-Perthes disease at the end of skeletal growth seems to depend on the extent of involvement and the presence of a growth arrest. A varus osteotomy produces more significant shortening than other methods of treatments. The age at the onset of symptoms and sex do not influence the amount of LLD, but early onset of the disease can result in more severe limb shortening.

Early results of revision acetabular cup using antiprotrusio reconstruction rings and allografts

Background: Hip arthroplasty is one of the most frequently performed orthopedic procedures with high scores of success while its most common complication is aseptic loosening of the acetabular component, which may result from host bone loss or even from pelvis discontinuity. The purpose of the study was to evaluate results in patients after revision acetabular arthroplasty with reconstruction rings and allografts. Materials and Methods: Retrospective data was collected from 69 revisions of acetabular components, performed in a group of 69 treated patients (the mean age 65.1 years). Before surgery, the patients had bone defects of type IIb (n = 5), IIc (n = 20), IIIa (n = 27) or IIIb (n = 17), according to Paprosky et al. Results: The mean followup period of the patients was 7.2 years (range 3-19 years). A Kaplan–Meier analysis showed that a 3- and 10 year survival rate was 92.8% and 84.8% respectively, using further revision for any reason of the acetabular device as an end point. Eight patients revealed implant related complications. Four patients presented with ring loosening, one with a loose acetabular polyethylene cup, two hips demonstrated recurrent dislocations and one patient was with deep infection. Regarding the remaining 61 patients without re-revision surgery, the mean Harris hip score improved from 30.5 to 73.8 points. Conclusion: A modified, antiprotrusion cage provides an acceptable survival rate and radiological results, but complications could still be expected. It seems that the observed massive bone loss with pelvic discontinuity and an insufficient fixation of the cage to the ischium may result in implant loosening. Stable fixation of the ischial ring flange with screws is an essential condition to expect a good outcome.

Correlations between BMP-4 gene expression, heterotopic ossification and function after uncemented total hip replacement.

BACKGROUND Heterotopic ossification (HO) is the abnormal, non-neoplastic presence of lamellar bone in soft tissue. Bone morphogenetic proteins (BMP) are among factors that may lead to HO. The purpose of the study was to evaluate correlations between BMP-4 gene expression and HO and the influence of those factors on outcomes of cementless total hip replacement (THR). PATIENTS AND METHODS A series of sixty-four (64) patients were enrolled. The patients were at a mean age of 52.3 years and all of them had undergone unilateral THR. Mean duration of follow-up was 56.74 months. At the last follow-up visit, 1 ml blood samples were collected and BMP-4 gene expression was measured by the RT-PCR technique. Hip radiographs were also obtained and a clinical examination was performed during that visit. RESULTS A strong statistical correlation was observed between HO grades according to Brookers scale and BMP-4 expression levels (rho=0.946, p<0.0001), while there was no correlation between clinical outcomes according to the Harris Hip Score (HHS) and Brookers grades (rho= -0.188, p=0.3) as well as between Harris hip scores and BMP-4 expression levels (rho=0.1, p=0.6). CONCLUSIONS BMP-4 expression strongly correlates with HO as measured by Brookers scale and may play a role in the aetiology of this condition. The over-expression of BMP-4 may exert a certain influence on ectopic bone formation after total hip arthroplasty.

Fracture of the Femoral Stem as a Rare Complication of Total Hip Arthroplasty. Cases Report

The aim of this paper is to present the femoral stem fracture as a rare complication of total hip arthroplasty and describe further management in such cases. We present 5 cases of stem fracture in the Mittelmeier prosthe-sis which occurred from 8 to 29 years after the primary procedure. In three cases, the primary hip arthroplasty was performed due to dysplastic coxarthrosis. The remaining two patients had idiopathic and post-traumatic coxarthrosis. The four female patients underwent revision hip arthroplasty with stem replacement. One patient refused surgical treatment and has been followed up at the outpatient clinic. Annual clinical and radiological examination is an approved method for detecting late complications Hip arthroplasty should be performed at specialised centres where relevant prostheses and instruments are used. A transfemoral approach and the use of revision stems anchored in the femoral shaft is a method of choice for revision procedures performed due to stem fractures.

Radial Extracorporeal Shockwave Therapy and Ultrasound Therapy in the Treatment of Tennis Elbow Syndrome

BACKGROUND Both ultrasound and radial shockwave therapies are used to treat tennis elbow syndrome. The aim of this study was to compare the therapeutic efficacy of both therapies by assessing the reduction in pain intensity and frequency, restoration of mobility, and reduction in the need for pain medication. MATERIAL AND METHODS The study enrolled 60 people, who were randomly divided into two groups of 30 patients: those treated by radial shockwave therapy and those treated by ultrasound therapy. Radial shockwave therapy consisted of 3 sessions at weekly intervals. Ultrasound therapy consisted of 10 treatments performed daily. The clinical status of the patients before treatment, just after treatment, and after 8 weeks was assessed with the Leitinen questionnaire and a visual analogue scale (VAS). RESULTS Pain reduction, as assessed by VAS scores, was observed in both groups, who were not different at baseline (p=0.807). While both therapies were effective (p<0.005), mean pain intensity assessed by VAS scores in patients treated by radial shockwave therapy was significantly lower compared to those treated by ultrasound therapy; this relationship was present just after treatment completion (p=0.001) and at 8 weeks after treatment completion (p=0.002). CONCLUSIONS 1. Both radial shockwave and ultrasound therapies cause a reduction in the intensity and frequency of pain that persists for at least 8 weeks, reducing the need for pain medication and improving the function of the treated upper limb. 2. Ultrasound therapy is less effective than radial shockwave therapy.

Metallographic evaluation of hip joint implants wear and electrochemical implants potential

We performed metallographic evaluations of implants, removed during revision hip arthroplasty. The implants were evaluated for electrochemical potentials and the presence of wear products on the implants surface. A total of 50 patients (50 hips) underwent revision hip arthroplasty during the years 2007-2009 for aseptic loosening. The mean follow-up from primary hip replacement to revision was 10.1 years (from six months to 17 years). All hip joint implants removed during the revision arthroplasty were submitted to metallographic analysis and all heads were submitted to analysis under a scanning microscope. All polyethylene (PE) cups and inserts showed numerous features of wear (friction wear, plastic deformation and creeping, fatigue wear and degradation), six PE cups were broken. In six ceramic cups, only friction wear features were found; one of them was mechanically broken. In all heads articulating on PE not one had any mechanical damage. Heads of ceramic implants in ceramic-ceramic articulation undergo abrasive wear. None of the studied stems (cemented or uncemented) revealed any features of wear. Areas of titanium crystals (formed by electrolytic sedimentation of metals) were macroscopically identified on the sliding surface of six heads that was confirmed by chemical composition and scanning microscope. In the course of prosthesis use, wear products are produced and transferred onto the sliding surfaces of implant heads and cups via ways other than purely mechanical contact. It has been confirmed that metals used for implant construction, make galvanic cells with different electrochemical potentials.