Kimmo Mattila - Academia.edu (original) (raw)

Papers by Kimmo Mattila

PubMed, 1998

Background and aims: Chronic quadriceps femoris muscle compartment syndrome is described. Materia... more Background and aims: Chronic quadriceps femoris muscle compartment syndrome is described. Material and methods: Over a 13 year period nine patients were diagnosed, treated surgically by fasciotomy and followed up at a referral center specialized in sports traumatology. There were four power lifters, three body builders, one endurance walker and one cyclist in the series. The use of anabolic steroids was admitted by four of the nine patients. The patients complained of gradually worsening pain on the anterolateral side of the thigh during training. Initially the pain appeared only at the end of the training session. As the syndrome became more severe, the pain began earlier during exercise and gradually became worse preventing maximal training. Skeletal radiographs and ultrasound examinations were normal, except in two patients, who had a positive echography finding with local atrophy. MRI examination confirmed the US diagnosis. Results and conclusions: As conservative treatment did not provide relief of symptoms, a fasciotomy anterior to the iliotibial tract was performed bilaterally to seven patients and unilaterally to two patients. Biopsies from the atrophied sites showed muscle cell necrosis. All the patients recovered well after the surgery and were able return to their original level of sport. The only complication of surgery was a postoperative hematoma in one patient, which delayed the beginning of the training, but did not result in any persistent complaints.

British Journal of Sports Medicine, Apr 12, 2006

Background: Hamstring injuries are common especially in athletes. Partial and complete tears of t... more Background: Hamstring injuries are common especially in athletes. Partial and complete tears of the proximal origin may cause pain and functional loss. Objective: To evaluate the results of surgical treatment for partial proximal hamstring tears. Methods: Between 1994 and 2005, 47 athletes (48 cases, 1 bilateral) with partial proximal hamstring tears were operated on. The cases were retrospectively analysed. Before surgery, 42 of the patients had undergone conservative treatment with unsatisfactory results, whereas in five patients the operation was performed within four weeks of the injury. Results: The mean length of the follow up was 36 months (range 6-72). The result of the operation was rated excellent in 33 cases, good in nine, fair in four, and poor in two. Forty one patients were able to return to their former level of sport after an average of five months (range 1-12). Conclusion: In most cases, excellent or good results can be expected after surgical repair of partial proximal hamstring tears even after conservative treatment has failed.

BACKGROUND AND PURPOSE: Previous literature is vague on the prevalence and exact nature of absces... more BACKGROUND AND PURPOSE: Previous literature is vague on the prevalence and exact nature of abscesses in tonsillar infections, ranging from intratonsillar and peritonsillar collections to deep extension involving the parapharyngeal and retropharyngeal spaces. MR imaging has excellent diagnostic accuracy in detecting neck infections and can potentially clarify this issue. We sought to characterize the spectrum of MR imaging findings regarding tonsillar infections. MATERIALS AND METHODS: We conducted a retrospective cohort study of emergency neck MR imaging scans of patients with tonsillar infections. Imaging data were assessed in terms of signs of infection and the location of abscesses and were compared with clinical findings, final diagnoses, and surgical findings as reference standards. RESULTS: The study included 132 patients with tonsillar infection. Of these, 110 patients (83%) had $1 abscess (99 unilateral, 11 bilateral; average volume, 3.2 mL). Most abscesses were peritonsillar, and we found no evidence of intratonsillar abscess. Imaging showed evidence of parapharyngeal and retropharyngeal extension in 36% and 10% of patients, respectively. MR imaging had a high positive predictive value for both abscesses (0.98) and deep extension (0.86). Patients with large abscesses and widespread edema patterns had a more severe course of illness. CONCLUSIONS: Emergency neck MR imaging can accurately describe the extent and nature of abscess formation in tonsillar infections.

Journal of Bone and Joint Surgery, 2021

Background: In cementless total hip arthroplasty, femoral stems should preferably not migrate at ... more Background: In cementless total hip arthroplasty, femoral stems should preferably not migrate at all postoperatively. This goal is difficult to achieve in postmenopausal women with impaired bone quality. Here, we explored the clinical importance of initial stem migration, measured by radiostereometric analysis (RSA), in women who underwent quantitative computed tomography (CT) of the involved hip preoperatively. Methods: A prospective cohort of 65 postmenopausal women (mean age, 69 years) with hip osteoarthritis and Dorr type-A or B femoral anatomy underwent total hip arthroplasty with implantation of a tapered, single-wedge femoral stem. Volumetric bone mineral density (BMD) was measured using quantitative CT. Femoral stem translation and rotation were measured using model-based RSA within 3 days after the surgical procedure and were repeated at 3, 5, and 11 months. Postoperative recovery parameters included walking speed, walking activity, and patient‐reported outcome measures. Su...

Contrast Media & Molecular Imaging, 2017

Microbiologic cultures are not infrequently negative in patients with a histopathologic diagnosis... more Microbiologic cultures are not infrequently negative in patients with a histopathologic diagnosis of chronic osteomyelitis. Culture-negative cases may represent low-grade infections with a lower metabolic activity than culture-positive cases. 18F-FDG PET could potentially detect such a difference. We determined whether the level of 18F-FDG PET uptake differs in patients with culture-negative and culture-positive osteomyelitis. We reviewed the clinical charts of 40 consecutive patients, who had diagnostic 18F-FDG PET for a suspected bone infection. Twenty-six patients were eligible with a confirmed diagnosis based on microbiologic cultures and/or histopathologic examination. Sixteen of 26 patients had chronic osteomyelitis. Eight of them had positive cultures, seven had negative cultures, and one patient had no cultures of the biopsy specimen. The patients with histologically and/or microbiologically proven osteomyelitis were correctly interpreted as true positive in the routine clin...

Scandinavian Journal of Surgery, 2012

Background and Aims: Stress fractures are common overuse injuries in athletes. Medial malleolar s... more Background and Aims: Stress fractures are common overuse injuries in athletes. Medial malleolar stress fractures are rare but they have an important clinical relevance because of their tendency to cause considerable disability and loss of time in sports without proper treatment. The diagnosis of medial malleolar stress fracture is often a challenge and it is therefore often delayed which may cause even further problems in the treatment. The purpose of this study was to increase the awareness of medial malleolar stress fractures as a possible cause for medial ankle pain and to stress the importance of MRI in the diagnostics as well as to evaluate the results of surgical treatment. Patients and Methods: Between 1995 and 2008, a total of ten athletes with a medial malleolar stress fracture were operated at our centre. All operated cases during those years were included in the study. The cases were retrospectively analyzed. Return to pre-injury level of sport was evaluated and considere...

Oral Radiology

Objectives To determine the diagnostic accuracy of emergency magnetic resonance imaging (MRI) in ... more Objectives To determine the diagnostic accuracy of emergency magnetic resonance imaging (MRI) in odontogenic maxillofacial infections, the clinical and surgical significance of MRI findings, and whether MRI can identify the tooth responsible for the infection. Methods A retrospective cohort study reviewed 106 emergency neck MRI scans of patients with neck infections of odontogenic origin. The diagnostic accuracy of MRI in identifying abscesses was studied relative to surgical findings. Correlations were analyzed between various MRI findings and clinical results and outcomes, such as the surgical approach (intraoral vs. extraoral). The ability of MRI findings to predict the causative tooth was assessed in a blinded multi-reader setting. Results Of the 106 patients with odontogenic infections, 77 (73%) had one or more abscesses. Imaging showed a sensitivity, specificity, and accuracy of 0.95, 0.84, and 0.92, respectively, for MRI diagnosis of an odontogenic abscess. Among the imaging ...

European Radiology, 2021

Objectives Due to its superior soft-tissue contrast and ability to delineate abscesses, MRI has h... more Objectives Due to its superior soft-tissue contrast and ability to delineate abscesses, MRI has high diagnostic accuracy in neck infections. Whether MRI findings can predict the clinical course in these patients is unknown. The purpose of this study was to determine the clinical and prognostic significance of various MRI findings in emergency patients with acute neck infections. Materials and methods We retrospectively reviewed the 3-T MRI findings of 371 patients with acute neck infections from a 5-year period in a single tertiary emergency radiology department. We correlated various MRI findings, including retropharyngeal (RPE) and mediastinal edema (ME) and abscess diameter, to clinical findings and outcomes, such as the need for intensive care unit (ICU) treatment and length of hospital stay (LOS). Results A total of 201 out of 371 patients (54%) with neck infections showed evidence of RPE, and 81 out of 314 patients (26%) had ME. Both RPE (OR = 9.5, p < 0.001) and ME (OR = 5...

Aim: Adductor muscle strains are common injuries in contact related sports such as ice hockey and... more Aim: Adductor muscle strains are common injuries in contact related sports such as ice hockey and football. Most of these injuries are treated conservative with good results. However, there is no consensus on the best treatment of partial ruptures of the adductor longus tendon among athletes as non-operative and operative therapies seems both provide good results. Non-operative therapy rests on physiotherapy and operative treatment on tenotomy. MRI is an effective tool for grading the injury and is widely used for the initial diagnostics of an adductor longus injury. Methods: A31-year old professional ice hockey player sustained a partial rupture of the adductor longus tendon which did not heal by physiotherapy. Surgery was undertaken 20 weeks after primary injury, and 16 weeks later he returned to play (RTP) successfully with no relapse during 52 weeks of followup. He was followed up with a series of MRI and hip strength tests during recovery from non-operative and operative treatm...

Scandinavian Journal of Surgery, 2005

Background and Aims: Radiostereometric analysis (RSA) allows accurate three-dimensional measureme... more Background and Aims: Radiostereometric analysis (RSA) allows accurate three-dimensional measurements of micromotion in skeletal structures. The current RSA techniques are based on the analysis of scanned plain films. This study was undertaken to compare digital filmless RSA technique to conventional scanning technique using a phantom model of the ankle mortise. Material and Methods: In the first experiment, the relative displacement of the markers inserted to the fibula in relation to the markers inserted to the tibia was studied by means of double examinations and the precision of DICOM images were compared to scanned images of printed radiographs. In the second experiment, the film pair of double examination was re-imported or re-scanned and self-compared in order to show merely the error related to the image processing. Results: The precision of RSA using scanned images of printed radiographs was compatible to DICOM images. However, the mean error of rigid body fitting (ME) value...

Clinical Orthopaedics & Related Research, 2016

Background In clinical trials of THA, model-based radiostereometric analysis (RSA) techniques may... more Background In clinical trials of THA, model-based radiostereometric analysis (RSA) techniques may be less precise than conventional marker-based RSA for measurement of femoral stem rotation. We verified the accuracy and clinical precision of RSA based on computeraided design models of a cementless tapered wedge femoral stem. Questions We asked: (1) Is the accuracy of model-based RSA comparable to that of marker-based RSA? (2) What is the clinical precision of model-based RSA? Methods Model-based RSA was performed using combined three-dimensional computer-aided design models of the stem and head provided by the implant manufacturer. The accuracy of model-based RSA was compared with that of marker-based RSA in a phantom model using micromanipulators for controlled translation in three axes (x, y, z) and rotation around the y axis. The clinical precision of model-based RSA was evaluated by double examinations of patients who had arthroplasties (n = 24) in an ongoing trial. The clinical precision was defined as being at an acceptable level if the number of patients needed for a randomized trial would not differ from a trial done with conventional marker-based RSA (15-25 patients per group). Results The accuracy of model-based RSA was 0.03 mm for subsidence (translation along the y axis) (95% CI for the difference between RSA measurements and actual displacement measured with micrometers, À0.03-0.00) and 0.39°for rotation around the y axis (95% CI, À0.41 to À0.06). The accuracy of marker-based RSA was 0.06 mm for subsidence (95% CI, À0.04-0.01; p = 0.728 compared with model-based RSA) and 0.18°for the y axis rotation (95% CI, À0.23 to À0.07; p = 0.358). The clinical precision of model-based RSA was 0.14 mm for subsidence (95% CI for the difference between double examinations, À0.02-0.04) and 0.79°for the y axis rotation (95% CI, À0.16-0.18). Conclusions The accuracy of model-based RSA for measurement of the y axis rotation was not quite as high as that of marker-based RSA, but its clinical precision is at an acceptable level. Clinical relevance Model-based RSA may be suitable for clinical trials of cementless tapered wedge femoral stem designs. The institution of the authors (SNF, SF, NM, KM, JJA, HTA) has received funding from Academy of Finland, Amgen Inc, and the Government of Finland. Each author certifies that he or she, or a member of his or her immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research 1 editors and board members are on file with the publication and can be viewed on request. Each author certifies that his or her institution approved or waived approval for the reporting of this investigation and that all investigations were conducted in conformity with ethical principles of research.

The bone & joint journal, 2014

We have compared three different methods of treating symptomatic non-traumatic tears of the supra... more We have compared three different methods of treating symptomatic non-traumatic tears of the supraspinatus tendon in patients above 55 years of age. A total of 180 shoulders (173 patients) with supraspinatus tendon tears were randomly allocated into one of three groups (each of 60 shoulders); physiotherapy (group 1), acromioplasty and physiotherapy (group 2) and rotator cuff repair, acromioplasty and physiotherapy (group 3). The Constant score was assessed and followed up by an independent observer pre-operatively and at three, six and twelve months after the intervention. Of these, 167 shoulders were available for assessment at one year (follow-up rate of 92.8%). There were 55 shoulders in group 1 (24 in males and 31 in females, mean age 65 years (55 to 79)), 57 in group 2 (29 male and 28 female, mean age 65 years (55 to 79)) and 55 shoulders in group 3 (26 male and 29 female, mean age 65 years (55 to 81)). There were no between-group differences in the Constant score at final follo...

Skeletal Radiology, 2012

Purpose To evaluate the feasibility and intra-and interobserver agreement of CBCT arthrography of... more Purpose To evaluate the feasibility and intra-and interobserver agreement of CBCT arthrography of wrist ligaments, triangular fibrocartilaginous complex (TFCC), and to assess the sensitivity (SE), specificity (SP), accuracy (ACC), and positive and negative predictive value (PPV, NPV) of CBCT arthrography in the diagnosis of scapholunate (SLL) and lunotriquetral (LTL) ligament tears, TFCC, and cartilage abnormalities of the scaphoid and lunate with their corresponding radial surfaces (scaphoid and lunate fossa) using a novel, mobile, dedicated extremity CBCT scanner. Materials and methods Fifty-two consecutively enrolled subjects (26 M, 26 F, mean age 38 years, range 18-66 years) with suspected wrist ligament tears underwent CBCTarthrography before normally scheduled MR arthrography.An extremity CBCT was used for imaging with isotropic voxel size of 0.4 × 0.4 × 0.4 mm 3. Subsequent routine 1.5 T MRI was performed using a dedicated wrist coil.Two observers reviewed the anonymized CBCT images twice for contrast enhancement (CE) and technical details (TD), for tears of the SLL, LTL, and TFCC. Also, cartilage abnormalities of the scaphoid and lunate with their corresponding radial surfaces (scaphoid and lunate fossa) were evaluated. Inter-and intraobserver agreement was determined using weighted kappa statistics. Since no surgery was performed, MRI served as a reference standard, and SE and SP, ACC, PPV, and NPV were calculated. Results Intra-and interobserver kappa values for both readers (reader 1/reader 2; first reading/second reading) with 95 % confidence limits were: CE 0.

Operative Techniques in Sports Medicine, 2009

Foot and Ankle Surgery, 2004

Rupture of flexor hallucis longus tendon is rare and the literature is mainly based on case repor... more Rupture of flexor hallucis longus tendon is rare and the literature is mainly based on case reports. It probably is more common than reported. We present a case of chronic rupture of flexor hallucis longus tendon in a male world class distance runner. First conservative treatment, an attempt of suturing the and finally the first reported case where successful anatomical repair with free tendon graft is used.

Clinical Journal of Sport Medicine, 1999