Pekka Ylinen
Helsinki University Central Hospital
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Archives of Orthopaedic and Trauma Surgery | 1993
Seppo Santavirta; Kaj Tallroth; Pekka Ylinen; H. Suoranta
SummaryWe surgically treated 16 patients with Bertolottis syndrome (chronic, persistent low back pain and radiographically diagnosed transitional lumbar vertebra). Eight had posterolateral fusion and another eight resection of the transitional articulation. Thirteen patients had in addition to the chronic low back pain, suffered from repeated episodes or chronic sciatica. In six cases with resection treatment, local injections were administered at the transitional articulation before deciding for resection of the transitional joint; each patient reported transient relief of pain, while this preoperative test did not correlate with successful outcome of treatment. Six patients had to be treated with second operations. Ten of the 16 operatively treated patients showed improvement of the low back pain, and this result was similar in the group treated with fusion and in that treated with resection. Seven had no low back pain at follow-up, and the improvement according to the Oswestry pain scale was similar in the two groups, and statistically significant. Eleven patients still had persisting episodes of sciatica (versus 13 preoperatively). The average disability according to the Oswestry total disability scale was 30%, corresponding with moderate outcome, and both operatively treated groups did equally well. At follow-up the first disc above the fused segments was found to be degenerated in seven out of eight cases, and in the group treated with resection the first disc above the transitional vertebra was degenerated in five cases. As conservatively treated controls, we had 16 comparable, but not randomly chosen patients whose age and type and duration of pain prior to the first clinical examination, and the length of follow-up were similar to those in the operatively treated group. The operatively treated patients had slightly better Oswestry pain score (mean 1.9 versus 2.5; statistically significant), while in regard to the total Oswestry disability scale, the results did not differ. We suggest operative treatment only to very selected patients with Bertolottis syndrome. Patients with no disc deneration and whose chronic pain is truly associated with the transitional joint may be treated with resection of the transverse process. Patients with similar pain and with degeneration of the disc below but not above the transitional vertebra may have alleviation of pain and disability after posterolateral fusion.
Acta Orthopaedica | 2013
Tarvo Sillat; Gonçalo Barreto; Paul Clarijs; Antti Soininen; Mari Ainola; Jukka Pajarinen; Matti Korhonen; Yrjö T. Konttinen; Regina Sakalyte; Mika Hukkanen; Pekka Ylinen; Dan Nordström
Background and purpose Degenerating cartilage releases potential danger signals that react with Toll-like receptor (TLR) type danger receptors. We investigated the presence and regulation of TLR1, TLR2, and TLR9 in human chondrocytes. Methods We studied TLR1, TLR2, TLR4, and TLR9 mRNA (qRT-PCR) and receptor proteins (by immunostaining) in primary mature healthy chondrocytes, developing chondrocytes, and degenerated chondrocytes in osteoarthritis (OA) tissue sections of different OARSI grades. Effects of a danger signal and of a pro-inflammatory cytokine on TLRs were also studied. Results In primary 2D-chondrocytes, TLR1 and TLR2 were strongly expressed. Stimulation of 2D and 3D chondrocytes with a TLR1/2-specific danger signal increased expression of TLR1 mRNA 1.3- to 1.8-fold, TLR2 mRNA 2.6- to 2.8-fold, and TNF-α mRNA 4.5- to 9-fold. On the other hand, TNF-α increased TLR1 mRNA] expression 16-fold, TLR2 mRNA expression 143- to 201-fold, and TNF-α mRNA expression 131- to 265-fold. TLR4 and TLR9 mRNA expression was not upregulated. There was a correlation between worsening of OA and increased TLR immunostaining in the superficial and middle cartilage zones, while chondrocytes assumed a CD166× progenitor phenotype. Correspondingly, TLR expression was high soon after differentiation of mesenchymal stem cells to chondrocytes. With maturation, it declined (TLR2, TLR9). Interpretation Mature chondrocytes express TLR1 and TLR2 and may react to cartilage matrix/chondrocyte-derived danger signals or degradation products. This leads to synthesis of pro-inflammatory cytokines, which stimulate further TLR and cytokine expression, establishing a vicious circle. This suggests that OA can act as an autoinflammatory disease and links the old mechanical wear-and-tear concept with modern biochemical views of OA. These findings suggest that the chondrocyte itself is the earliest and most important inflammatory cell in OA.
Archives of Orthopaedic and Trauma Surgery | 2009
Esa Koskinen; Pekka Paavolainen; Antti Eskelinen; Arsi Harilainen; Jerker Sandelin; Pekka Ylinen; Kaj Tallroth; Ville Remes
AimThe purpose of our study was to evaluate retrospectively the mid-term results of the Miller-Galante II (Zimmer, Warsaw, USA) unicondylar knee arthoplasty (UKA).MethodThe study included 46 patients with medial UKAs. Mean follow-up time was 7.0 years (range 2.7–13.1 years).ResultsSurvival rate of the prosthesis was 86.6% (95% CI 73.7–99.6) at 7 years. The mean clinical and functional Knee Society Scores had increased from 51 and 62 points preoperatively to 76 and 93 points (P < 0.001) postoperatively. Five of the 46 knees were revised because of excessive wear of the polyethylene liner, and three due to progression of the osteoarthritis in the lateral compartment of the knee.ConclusionSurvival of this fixed-bearing UKA was not as good as previously reported and polyethylene wear seems to be a more common problem than previously assumed.
Acta Orthopaedica | 2009
Antti Eskelinen; Ville Remes; Pekka Ylinen; Ilkka Helenius; Kaj Tallroth; Timo Paavilainen
Background and purpose Historically, a Schanz osteotomy of the femur has been used to reduce limp in patients with severely dysplastic hips. In such hips, total hip arthroplasty is a technically demanding operation. We report the long-term results of cementless total hip arthroplasty in a group of patients who had all undergone a Schanz osteotomy earlier. Patients and methods From 1988 through 1995, 68 total hip replacements were performed in 59 consecutive patients previously treated with a Schanz osteotomy. With the cup placed at the level of the true acetabulum, a shortening osteotomy of the proximal part of the femur and distal advancement of the greater trochanter were performed in 56 hips. At a mean of 13 (9–18) years postoperatively, we evaluated these patients clinically and radiographically. Results The mean Harris hip score had increased from 51 points preoperatively to 93 points. Trendelenburg sign was negative and there was good or slightly reduced abduction strength in 23 of 25 hips that had not been revised. There were 12 perioperative complications. Only 1 cementless press-fit porous-coated cup was revised for aseptic loosening. However, the 12-year survival rate of these cups was only 64%, as 18 cups underwent revision for excessive wear of the polyethylene liner and/or osteolysis. 6 CDH femoral components had to be revised due to technical errors. Interpretation Our results suggest that cementless total hip arthroplasty combined with a shortening osteotomy of the femur and distal advancement of the greater trochanter can be recommended for most patients with a previous Schanz osteotomy of the femur. Because of the high incidence of liner wear and osteolysÍs of modular cementless cups in this series, nowadays we use hard-on-hard articulations in these patients.
Archives of Orthopaedic and Trauma Surgery | 1993
Seppo Santavirta; V. Turunen; Pekka Ylinen; Yrjö T. Konttinen; Kaj Tallroth
SummaryWe reviewed 15 patients with Charcot-Marie-Tooth disease who were treated with foot or ankle fusions. Altogether, 26 feet were treated with fusions and the average follow-up time was 14 years. In half of the patients the principal symptom leading to fusion operation was instability of the ankle. In four patients, in two of them bilaterally, soft tissue corrections were performed before the fusion. In 21 cases, a subtalar triple arthrodesis was performed and each time correction to neutral position was the aim. In six feet, the triple arthrodesis was complemented by soft tissue plasties, e.g., plantar release, Achilles elongation, or transposition of tibial or peroneal tendons in order to achieve proper balance. Other primary fusions were a Grice-type fusion in one case, pantalar arthrodesis in one case, talocrural fusion in one case, and interphalangeal fusions in both feet in one patient with extreme claw foot. In four cases the triple arthrodesis failed to fuse (three nonunions and one delayed union), and new fusions were successful in three of them. The one pantalar fusion in the series was done for a 58-year-old man with late onset of the disease who had a very severe cavovarus deformity at the time of the operation, and this fusion failed to unite. In 17 of 26 feet, other operations than the primary fusion were performed, and five feet were operated on three or four times. In four feet the result was judged as excellent, in 15 good, in four fair, and in three poor. There were not more poor results in patients followed up for more than 15 years than in those whose follow-up was shorter. Evaluation of the surgical results in the present series suggests that triple arthrodesis can preserve acceptable function in the majority of patients with foot deformities and instabilities which are caused by Charcot-Marie-Tooth disease.
Acta Orthopaedica Scandinavica | 1998
Vesa Saikko; Juha Nevalainen; Hannu Revitzer; Pekka Ylinen
We used a hip joint simulator to compare the metal release from CoCr/CoCr, CoCr/PE, and alumina/PE total hip articulations. The metal release was quantified by analyzing the Co, Cr, and Ni contents of the bovine serum lubricant used with atomic absorption spectroscopy. CoCr/CoCr articulations released substantial amounts of metal, whereas CoCr/PE was equal to the control, alumina/PE, in that metal release was negligible. The metal release was in accordance with the known clinical wear rates of CoCr/CoCr articulations. The largest dimensional changes occurred in polyethylene cups, the penetrations of CoCr heads to the polyethylene cups being twice that of the alumina head, which is consistent with clinical experience. The research on the wear behavior of different materials, aiming to find a prosthesis with negligible wear, needs to be continued. Due to the substantial metal release, the CoCr/CoCr articulation is hardly the final solution of the wear problem in total hip arthroplasty.
Knee | 2011
Esa Koskinen; Ville Remes; Pekka Paavolainen; Arsi Harilainen; Jerker Sandelin; Kaj Tallroth; Jyrki Kettunen; Pekka Ylinen
The objectives of the present study were to find out the results and the factors affecting survival after primary knee arthroplasty with a cruciate-retaining prosthesis in severe valgus deformity. Forty-eight patients (52 knees) participated in the current follow-up study. All patients were followed at least 5 years or to first revision. Mean follow-up time was 9 years (range, 1 to 17 years).The Kaplan-Meier analysis revealed 79% (95% CI 68% to 91%) survival rate with revision for any reason and 81% (95% CI 70% to 93%) survival rate with revision for instability as an endpoint at 10 years. Preoperatively TFA was 23° (range, 15°-51°) in valgus and 7° (range, 21° valgus-4° varus) in valgus postoperatively. Of the 14 re-operated patients, eight were revised because of progressive postoperative medial collateral ligament instability. All re-operations were performed during the first 4 years of the follow-up. The mean TFA was 15.5° valgus postoperatively for those eight and the odds ratio for a revision was 2 (95% CI 1-3, p = 0.025) when compared to the rest of the study population. The residual valgus deformity increases the risk of re-operation and it should be avoided. If proper soft-tissue balance cannot be achieved or there is no functional medial collateral ligament present more constrained implants should be used. In selected cases where both bony correction and ligament balancing have properly been achieved the use of a cruciate-retaining type of prosthesis is justified.
Acta Orthopaedica Scandinavica | 1993
Arsi Harilainen; Jerker Sandelin; Pekka Ylinen; Veijo Vahvanen
We evaluated 52 unicompartmental PCA arthroplasties for primary (46) or secondary (6) arthrosis after 3 (2-5) years. Cementless fixation was used in 35 femoral and in 28 tibial components. There were indications for revision in 11 cases. Conversion to a total knee had been performed in 4 cases, and 1 tibial as well as 1 femoral component had been exchanged, mainly because of polyethylene wear with increasing deformity. 2 femoral components were loose and 1 had fractured.
The Journal of Rheumatology | 2013
Gonçalo Barreto; Tarvo Sillat; Antti Soininen; Pekka Ylinen; Abdelhakim Salem; Yrjö T. Konttinen; Ahmed Al-Samadi; Dan Nordström
Objective. Cartilage degeneration in osteoarthritis (OA) leads to release of potential danger signals. The aim of our study was to profile OA cartilage for the Toll-like receptor (TLR) danger signal receptors. Methods. Osteochondral cylinders from total knee replacements were graded using OA Research Society International score and stained for proteoglycans, collagenase-cleaved type II collagen, and TLR 1–10, which were analyzed histomorphometrically. Results. Grade 1 OA lesions contained 22%–55% TLR 1–9-positive cells in the surface zone, depending on the TLR type. In Grade 2 TLR, immunoreactivity was 60%–100% (p < 0.01) and it was even higher in Grades 3 and 4 (p < 0.01 vs Grade 1). TLR-positive cells in Grade 1 middle zone were low, 0–19.9%, but were 5.1%–32.7% in Grade 2 (p < 0.01) and 34%–83% in Grades 3–4 samples (p < 0.001). TLR values in Grade 5 were low (14.3%–28.7%; p < 0.001). In Grades 3–4 OA, cartilage matrix stained strongly for TLR. In Grade 1, COL2-3/4M was restricted to chondrocytes, but was increasingly seen in matrix upon progress of OA to Grade 4, and then declined. Conclusion. Cells in the gliding surface zone are fully equipped with TLR in mild OA. Their proportion increases and extends to the middle or even the deep zone, reflecting OA progression. COL2A-3/4M staining suggests Endo180-mediated intake for intralysosomal degradation by cathepsins in Grade 1, but in higher grades this chondrocyte-mediated clearance fails and the matrix demonstrates extensive collagenase-induced damage. Detached and/or partially degraded matrix components can then act as endogenous danger signals (damage-associated molecular patterns or DAMP) and stimulate increasingly TLR-equipped chondrocytes to inflammation. At the peak inflammatory response, soluble TLR may exert negative feedback, explaining in part the low TLR levels in Grade 5 OA.
Archives of Orthopaedic and Trauma Surgery | 2008
Eerik T Skyttä; Ville Remes; Yrjänä Nietosvaara; Kaj Tallroth; Leena Paimela; Pekka Ylinen
IntroductionThe results of different prostheses used for total elbow arthroplasty (TEA) in rheumatoid arthritis (RA) have been reported in only a few studies. Small differences in survival or function between implants have been reported. We retrospectively evaluated the results of 42 Souter-Strathclyde and Kudo TEAs.Materials and methodsBetween 1988 and 1994, 21 consecutive patients with RA and severe elbow destruction underwent a Souter-Strathclyde TEA. Between 1994 and 1998, another group comprising 21 consecutive patients with RA with severe elbow destruction underwent a Kudo TEA.ResultsThere were six revisions for the groups combined, including four aseptic loosenings, one fracture and one liner wear and metallosis. The 5-year survival for the Souter-Strathclyde and the Kudo were 85% (95% CI 69–100) and 95% (95% CI 85–100), respectively. The difference between the groups was not statistically significant as tested by the Cox regression analysis. The majority of the patients were free of pain at follow-up. More than half of the patients were able to perform only light housekeeping tasks and a considerable proportion even had difficulties in maintaining personal hygiene. The elbow range of motion improved only slightly after the operation.ConclusionBoth the Souter-Strathclyde and the Kudo TEAs provide good pain relief in the arthritic elbow leading to high patient satisfaction despite the residual disabilities. Only small differences in the results between the Souter-Strathclyde and the Kudo TEAs were found. More than half of the patients were able to perform only light housekeeping tasks and a considerable proportion even had difficulties in maintaining personal hygiene. The elbow range of motion improved only slightly after the operation.