Yrjänä Nietosvaara
Helsinki University Central Hospital
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Featured researches published by Yrjänä Nietosvaara.
Journal of Pediatric Orthopaedics | 1994
Yrjänä Nietosvaara; Kari Aalto; Pentti E. Kallio
In a prospective two-year study on urban (city of Helsinki) Finnish children, 72 acute patellar dislocations were observed. The calculated annual incidence rate was 43/100,000 in children under 16 years. A total of 28 knees (39%) had associated osteochondral fractures. These fractures comprised 15 capsular avulsions of the medial patellar margin and 15 loose intra-articular fragments detached from the patella and/or lateral femoral condyle. The intra-articular fragments were found only after spontaneous relocation of the patella. The femoral fracture constantly involved the edge of the articular surface in the middle third of the condylar arc.
Journal of Bone and Joint Surgery, American Volume | 2008
Sauli Palmu; Pentti E. Kallio; Simon T. Donell; Ilkka Helenius; Yrjänä Nietosvaara
BACKGROUND The treatment of acute patellar dislocation in children is controversial. Some investigators have advocated early repair of the medial structures, whereas others have treated this injury nonoperatively. The present report describes the long-term subjective and functional results of a randomized controlled trial of nonoperative and operative treatment of primary acute patellar dislocation in children less than sixteen years of age. METHODS The data were gathered prospectively on a cohort of seventy-four acute patellar dislocations in seventy-one patients (fifty-one girls and twenty boys) younger than sixteen years of age. Sixty-two patients (sixty-four knees) without large (>15 mm) intra-articular fragments were randomized to nonoperative treatment (twenty-eight knees) or operative treatment (thirty-six knees). Operative treatment consisted of direct repair of the damaged medial structures if the patella was dislocatable with the patient under anesthesia (twenty-nine knees) or lateral release alone if the patella was not dislocatable with the patient under anesthesia (seven knees). All but four patients who underwent operative treatment had a concomitant lateral release. The rehabilitation protocol was the same for both groups. The patients were seen at two years, and a telephone interview was conducted at a mean of six years and again at a mean of fourteen years. Fifty-eight patients (sixty-four knees; 94%) were reviewed at the time of the most recent follow-up. RESULTS At the time of the most recent follow-up, the subjective result was either good or excellent for 75% (twenty-one) of twenty-eight nonoperatively treated knees and 66% (twenty-one) of thirty-two operatively treated knees. The rates of recurrent dislocation in the two treatment groups were 71% (twenty of twenty-eight) and 67% (twenty-four of thirty-six), respectively. The first redislocation occurred within two years after the primary injury in twenty-three (52%) of the forty-four knees with recurrent dislocation. Instability of the contralateral patella was noted in thirty (48%) of the sixty-two patients. The only significant predictor for recurrence was a positive family history of patellar instability. The mode of treatment and the existence of osteochondral fractures had no clinical or significant influence on the subjective outcome, recurrent patellofemoral instability, function, or activity scores. CONCLUSIONS The long-term subjective and functional results after acute patellar dislocation are satisfactory in most patients. Initial operative repair of the medial structures combined with lateral release did not improve the long-term outcome, despite the very high rate of recurrent instability. A positive family history is a risk factor for recurrence and for contralateral patellofemoral instability. Routine repair of the torn medial stabilizing soft tissues is not advocated for the treatment of acute patellar dislocation in children and adolescents.
Acta Orthopaedica | 2005
Risto Nikku; Yrjänä Nietosvaara; Kari Aalto; Pentti E. Kallio
Background The best treatment for primary patellar dislocation has been the subject of debate. Surgery has been recommended for all patients or for special subgroups to improve outcome. We have previously reported similar 2-year results after closed or open treatment. This report concerns 127 patients who were re-evaluated by questionnaire at least 5 years after the primary onset. Patients and methods At baseline, the patients were randomized regarding closed treatment (57) or individually adjusted proximal realignment operation (70). All patients were re-evaluated after a mean follow-up of 7 (6-9) years. Results The outcomes were similar: the patients own overall opinion was excellent or good after closed treatment in 81% of cases and after operative treatment in 67%. Mean Kujala and Hughston VAS knee scores were 90 and 94, respectively, after closed treatment and 88 and 89 after operative treatment. The proportions of stable patellae were 30% and 36% for closed treatment and operative treatment, respectively. In a multivariate risk analysis, there was a correlation between a Kujala score of less than 90 and female sex (OR: 3.5; 95% CI: 1.4-9.0), loose bodies on radiographs (4.1; 1.2-15), and also an initial history of contralateral patellar instability (3.6; 0.9-15). There were 2 risk factors for recurrent instability: initial contralateral instability (4.9; 0.9-28) and young age (0.9; 0.8-1.0/year). Girls with open tibial apophysis had the worst prognosis for instability (88%; 95% CI: 77-98). Interpretation We do not recommend proximal realignment surgery for treatment of primary dislocation of the patella.
Acta Orthopaedica Scandinavica | 1997
Risto Nikku; Yrjänä Nietosvaara; Pentti E. Kallio; Kari Aalto; Jarl-Erik Michelsson
To assess whether initial surgery is beneficial for patients with primary dislocation of the patella, we carried out a prospective randomized study. Knee stability was examined under anesthesia, and associated injuries were excluded by diagnostic arthroscopy. 55 patients then had closed treatment and 70 patients were operated on with individually adjusted proximal realignment procedures. Surgery gave no benefit based on 2 years of follow-up. The subjective result was better in the non-operative group in respect of mean Houghston VAS knee score (closed 90, operative 87), but similar in terms of the patients own overall opinion and mean Lysholm II knee score. Recurrent instability episodes (redislocation or recurrent subluxation) occurred in 20 nonoperated and in 18 operated patients. Of these, 15 and 12, respectively, then suffered redislocations. Function was better after closed treatment. Serious complications occurred after surgery in 4 patients. In conclusion, the recurrence of patellar dislocation may be more frequent than reported, whatever the form of treatment. Routine operative management cannot be recommended for primary dislocation of the patella.
Archives of Orthopaedic and Trauma Surgery | 2000
Jan Lassus; Ville Waris; Jing-Wen Xu; Tian-Fang Li; Jumang Hao; Yrjänä Nietosvaara; Seppo Santavirta; Yrjö T. Konttinen
Abstract Aseptic loosening is an increasing problem in total hip replacement (THR). Chronic inflammatory reaction against implant wear particle results in collageno- and osteolysis, leading to loosening of the implant. Cytokines are known to play a major role in this particular inflammatory process [10]. The aim of the present study was to examine interleukin-8 (IL-8) in the synovial-like interface membrane (SLIM) and pseudocapsular tissue of THRs and to compare it to normal knee synovial membrane. Eleven patients suffering from aseptically loosened THRs were included. All the SLIM and pseudocapsular tissue samples were obtained during revision operations. Ten control samples of normal synovium were collected per arthroscopy from the superior recessus of the knee. For immunohistochemical IL-8 detection, polyclonal mouse anti-human immunoglobulin (Ig)G1 IL-8-primary antibody was used with the alkaline phosphatase anti-alkaline phosphatase (APAAP) method. Results were quantitated using the Vidas image analysis system. The highest count levels (mean ± SEM) were detected in SLIM tissue (386 ± 82 cells/mm2). The difference was statistically significant compared with pseudocapsular tissue (193 ± 36 cells/mm2) and control samples (18 ± 5 cells/mm2). Count levels in control tissue were on average 5% of the SLIM tissues values. The present study determines for the first time the cellular origin of IL-8 in aseptically loosened THRs and also quantitates the IL-8-producing cells in the periprosthetic tissue. The results reveal a high rise in IL-8 concentration in SLIM and in synovial tissues. This finding moves us one step forward in solving the complex network of multiple factors affecting loosening of hip implants.
Pediatric Radiology | 2005
Tiina H. Pöyhiä; Yrjänä Nietosvaara; Ville Remes; Mikko O. Kirjavainen; Jari Peltonen; Antti E. Lamminen
Purpose: To evaluate rotator cuff muscles and the glenohumeral (GH) joint in brachial plexus birth injury (BPBI) using MRI and to determine whether any correlation exists between muscular abnormality and the development of glenoid dysplasia and GH joint incongruity. Materials and methods: Thirty-nine consecutive BPBI patients with internal rotation contracture or absent active external rotation of the shoulder joint were examined clinically and imaged with MRI. In the physical examination, passive external rotation was measured to evaluate internal rotation contracture. Both shoulders were imaged and the glenoscapular angle, percentage of humeral head anterior to the middle of the glenoid fossa (PHHA) and the greatest thickness of the subscapular, infraspinous and supraspinous muscles were measured. The muscle ratio between the affected side and the normal side was calculated to exclude age variation in the assessment of muscle atrophy. Results: All muscles of the rotator cuff were atrophic, with the subscapular and infraspinous muscles being most severely affected. A correlation was found between the percentage of humeral head anterior to the middle of the glenoid fossa (PHHA) and the extent of subscapular muscle atrophy (rs=0.45, P=0.01), as well as between its ratio (rs=0.5, P P=0.01). Severity of rotator cuff muscle atrophy correlated with increased glenoid retroversion and the degree of internal rotation contracture. Conclusions: Glenoid retroversion and subluxation of the humeral head are common in patients with BPBI. All rotator cuff muscles are atrophic, especially the subscapular muscle. Muscle atrophy due to neurogenic damage apparently results in an imbalance of the shoulder muscles and progressive retroversion and subluxation of the GH joint, which in turn lead to internal rotation contracture and deformation of the joint.
Journal of Hand Surgery (European Volume) | 2011
Eeva Koskimies; Nina Lindfors; Mika Gissler; Jari Peltonen; Yrjänä Nietosvaara
PURPOSE To calculate the national incidence of upper limb deficiencies and associated infant mortality in children in Finland using the International Federation of Societies for Surgery of the Hand (IFSSH) classification. Radial ray deficiency, ulnar ray deficiency, central ray deficiency, transverse arrest, phocomelia, undergrowth, and constriction band syndrome with skeletal defects were evaluated. METHODS We reviewed upper limb deficiencies among all 753,342 births in Finland during 1993 to 2005 reported to the Finnish Register of Congenital Malformations. Classification of these upper limb deficiencies was done according to a modified IFSSH system. We calculated incidence, gender and side distributions, frequency of associated anomalies, and infant mortality rates in different subtypes of the deficiencies. Familial occurrence of congenital upper limb defects was recorded. RESULTS A total of 419 cases (234 male, 185 female) of upper limb deficiencies were identified. The national incidence of upper limb deficiencies was 5.56 per 10,000 births and 5.25 per 10,000 live births. The most common upper limb abnormality was radial ray deficiency (138), followed by subgroups of undergrowth (91), upper limb defects due to constriction band syndrome (51), central ray deficiency (41), and ulnar ray deficiency (33). Perinatal mortality was 14%. Infant mortality among children with upper limb deficiencies was 137 per 1,000 live births, compared with an overall infant mortality of 3.7 per 1,000 live births in Finland. Additional birth defects were found in 60% of these children. Prevalence of upper limb defects in relatives of the census population was 2% (11 of 419). CONCLUSIONS The national incidence of upper limb deficiencies is 5.25 per 10,000 live births. Congenital upper limb deficiencies are associated with additional birth defects in two thirds of cases. These children, especially children with radial ray deficiency, have a high perinatal mortality rate. When divided into subgroups using IFSSH classification, differences emerge in both associated anomalies and mortality.
Journal of Bone and Joint Surgery, American Volume | 2009
Yrjänä Nietosvaara; Reijo T Paukku; Sauli Palmu; Simon T. Donell
BACKGROUND The treatment of acute patellar dislocation in children is controversial. Some investigators have advocated early repair of the medial structures, whereas others have treated this injury nonoperatively. The present report describes the long-term subjective and functional results of a randomized controlled trial of nonoperative and operative treatment of primary acute patellar dislocation in children less than sixteen years of age. METHODS The data were gathered prospectively on a cohort of seventy-four acute patellar dislocations in seventy-one patients (fifty-one girls and twenty boys) younger than sixteen years of age. Sixty-two patients (sixty-four knees) without large (>15 mm) intra-articular fragments were randomized to nonoperative treatment (twenty-eight knees) or operative treatment (thirty-six knees). Operative treatment consisted of direct repair of the damaged medial structures if the patella was dislocatable with the patient under anesthesia (twenty-nine knees) or lateral release alone if the patella was not dislocatable with the patient under anesthesia (seven knees). All but four patients who underwent operative treatment had a concomitant lateral release. The rehabilitation protocol was the same for both groups. The patients were seen at two years, and a telephone interview was conducted at a mean of six years and again at a mean of fourteen years. Fifty-eight patients (sixty-four knees; 94%) were reviewed at the time of the most recent follow-up. RESULTS At the time of the most recent follow-up, the subjective result was either good or excellent for 75% (twenty-one) of twenty-eight nonoperatively treated knees and 66% (twenty-one) of thirty-two operatively treated knees. The rates of recurrent dislocation in the two treatment groups were 71% (twenty of twenty-eight) and 67% (twenty-four of thirty-six), respectively. The first redislocation occurred within two years after the primary injury in twenty-three (52%) of the forty-four knees with recurrent dislocation. Instability of the contralateral patella was noted in thirty (48%) of the sixty-two patients. The only significant predictor for recurrence was a positive family history of patellar instability. The mode of treatment and the existence of osteochondral fractures had no clinical or significant influence on the subjective outcome, recurrent patellofemoral instability, function, or activity scores. CONCLUSIONS The long-term subjective and functional results after acute patellar dislocation are satisfactory in most patients. Initial operative repair of the medial structures combined with lateral release did not improve the long-term outcome, despite the very high rate of recurrent instability. A positive family history is a risk factor for recurrence and for contralateral patellofemoral instability. Routine repair of the torn medial stabilizing soft tissues is not advocated for the treatment of acute patellar dislocation in children and adolescents.
Journal of Bone and Joint Surgery, American Volume | 2007
Mikko O. Kirjavainen; Ville Remes; Jari Peltonen; Pentti Kinnunen; Tiina Pöyhiä; Timo Telaranta; Markku Alanen; Ilkka Helenius; Yrjänä Nietosvaara
BACKGROUND The long-term results of surgical treatment of brachial plexus birth palsy have not been reported. We present the findings of a nationwide study, with a minimum five-year follow-up, of the outcomes of surgery for brachial plexus birth palsy in Finland. METHODS Of 1,717,057 newborns, 1706 with brachial plexus birth palsy requiring hospital treatment were registered in Finland between 1971 and 1997. Of these patients, 124 (7.3%) underwent surgery on the brachial plexus at a mean age of 2.8 months (range, 0.4 to 13.2 months). The most commonly performed surgical procedure was direct neurorrhaphy after neuroma resection. One hundred and twelve patients (90%) returned for a clinical and radiographic follow-up examination after a mean of 13.3 years. Activities of daily living were recorded on a questionnaire, and the affected limb was assessed with use of joint-specific functional measures. RESULTS Two-thirds (63%) of the patients were satisfied with the functional outcome, although one-third of all patients needed help in activities of daily living. One-third of the patients, including all nine with a clavicular nonunion from the surgical approach, experienced pain in the affected limb. All except four patients used the hand of the unaffected limb as the dominant hand. Shoulder function was moderate, with a mean Mallet score of 3.0. Both elbow and hand function were good, with a mean score on the Gilbert elbow scale of 3 and a mean Raimondi hand score of 4. Incongruence of the glenohumeral joint was noted in sixteen (16%) of the ninety-nine patients in whom it was assessed, and incongruence of the radiohumeral joint was noted in twenty-one (21%). The extent of the brachial plexus injury was found to be strongly associated with the final shoulder, elbow, and hand function in a multivariate analysis. CONCLUSIONS Following surgical treatment of brachial plexus birth palsy, substantial numbers of the patients continued to need help performing activities of daily living and had pain in the affected limb, with the pain due to a clavicular nonunion in one-fourth of the patients. The strongest prognostic factor predicting outcome appears to be the extent of the primary plexus injury.
Radiology | 2010
Tiina H. Pöyhiä; Antti Lamminen; Jari Peltonen; Mikko O. Kirjavainen; Patrick Willamo; Yrjänä Nietosvaara
PURPOSE To prospectively evaluate the use and optimal timing of ultrasonographic (US) screening for posterior shoulder subluxation in infantswith brachial plexus birth injury (BPBI). MATERIALS AND METHODS Approval of the ethics committee and informed consent of guardians was obtained. This population-based prospective study included neonates with BPBI who were born in Helsinki from January 1, 2003 through December 31, 2006, and in whom BPBI was verified with sequential clinical examinations. US was performed at 1, 3, 6, and 12 months. Size (width and height) of the humeral head and its ossification center and congruency of the shoulder (alpha angle) were measured. Frequency of BPBI and permanent changes were evaluated. This study also included patients who were referred from the tertiary catchment area. For statistical analysis, 95% confidence intervals were calculated, and analysis of variance was performed. RESULTS BPBI was seen in 132 of 41980 neonates (3.1 per 1000). In 27 cases (0.64 per 1000), BPBI did not heal during the 1st year of life and was considered permanent. The humeral head and its ossification center were smaller on the affected side in permanent BPBI. Nine patients with permanent palsy had posterior subluxation of the humeral head depicted with US (alpha angle, >30 degrees ). In five patients, posterior subluxation [corrected] was detected at 3 months. Nineteen of 21 patients with BPBI from the tertiary catchment area had permanent palsy. Ten of 19 patients developed posterior subluxation of the shoulder, which was verified with US. Altogether, three of these cases were not detected by surgeons. Posterior subluxation of the humeral head developed during the 1st year of life in one-third of patients with permanent BPBI. In more than one-half (55% [five of nine]) of the patients, posterior subluxation [corrected] was detected with US at 3 months, and in 89% (eight of nine), it was detected at 6 months. CONCLUSION US is a fast and useful tool for diagnosis of posterior subluxation of the humeral head, and examination of the glenohumeral joint should be performed at 3 and 6 months of age in infants with BPBI if symptoms persist.